阅读说明：本技术 半导体装置及半导体装置的制造方法 (Semiconductor device and method for manufacturing semiconductor device ) 是由 安部英俊 池永诚 高本健生 于 2019-07-18 设计创作，主要内容包括：半导体装置具备半导体元件、导线框、导通部件、树脂组成物、以及封固树脂。上述半导体元件具有在第一方向上彼此分离的元件主面及元件背面。上述导线框搭载上述半导体元件。上述导通部件与上述导线框接合,并使上述半导体元件与上述导线框导通。上述树脂组成物将上述导通部件与上述导线框的接合部分覆盖,并且使上述元件主面的一部分露出。上述封固树脂将上述导线框的一部分、上述半导体元件、以及上述树脂组成物覆盖。上述树脂组成物与上述导线框的接合强度优于上述封固树脂与上述导线框的接合强度,并且上述树脂组成物与上述导通部件的接合强度优于上述封固树脂与上述导通部件的接合强度。(The semiconductor device includes a semiconductor element, a lead frame, a conductive member, a resin composition, and a sealing resin. The semiconductor element has an element main surface and an element rear surface separated from each other in a first direction. The lead frame carries the semiconductor element. The conducting member is joined to the lead frame and conducts the semiconductor element to the lead frame. The resin composition covers a joint portion between the conductive member and the lead frame and exposes a portion of the main surface of the element. The sealing resin covers a part of the lead frame, the semiconductor element, and the resin composition. The bonding strength between the resin composition and the lead frame is better than that between the sealing resin and the lead frame, and the bonding strength between the resin composition and the conducting member is better than that between the sealing resin and the conducting member.)

1. A semiconductor device is characterized by comprising:

a semiconductor element having an element principal surface and an element back surface separated from each other in a first direction;

a lead frame on which the semiconductor element is mounted;

a conducting member which is joined to the lead frame and conducts the semiconductor element to the lead frame;

a resin composition covering a joint portion between the conductive member and the lead frame and exposing a portion of a main surface of the element; and

a sealing resin covering a part of the lead frame, the semiconductor element, and the resin composition,

the bonding strength between the resin composition and the lead frame is better than that between the sealing resin and the lead frame, and the bonding strength between the resin composition and the conducting member is better than that between the sealing resin and the conducting member.

2. The semiconductor device according to claim 1,

the lead frame includes: a chip pad having a pad main surface facing the same direction as the element main surface and a pad back surface facing the same direction as the element back surface; and a wire separated from the chip bonding pad,

the semiconductor element is mounted on the die pad such that the pad main surface faces the element back surface.

3. The semiconductor device according to claim 2,

the semiconductor device includes a back electrode formed on a back surface of the device,

the conductive member includes a conductive bonding material for bonding the semiconductor element to the die pad and electrically connecting the back surface electrode to the die pad,

the resin composition includes a die pad-side covering portion that covers a bonding portion of the conductive bonding material and the die pad.

4. The semiconductor device according to claim 3,

the conductive bonding material includes: an element contact surface that contacts the back surface electrode; a chip bonding pad contact surface contacting with the chip bonding pad; and a connecting surface connected to the element contact surface and the die pad contact surface,

the chip bonding pad side covering portion includes a chip bonding pad side first portion interposed between the connecting surface and the sealing resin.

5. The semiconductor device according to claim 4,

the chip pad side covering portion further includes a chip pad side second portion connected to the chip pad side first portion and interposed between the pad main surface and the sealing resin.

6. The semiconductor device according to claim 4 or 5,

the semiconductor element has an element side surface connected to the element main surface and the element rear surface,

the chip bonding pad side covering part further includes a chip bonding pad side third part connected to the chip bonding pad side first part and interposed between at least a part of the element side surface and the sealing resin.

7. The semiconductor device according to claim 6,

the die pad side covering portion further includes a die pad side fourth portion which is continuous with the die pad side third portion and is interposed between a part of the element main surface and the sealing resin.

8. The semiconductor device according to any one of claims 3 to 7,

the conductive bonding material is solder.

9. The semiconductor device according to any one of claims 3 to 8,

the back surface of the pad is exposed from the sealing resin.

10. The semiconductor device according to any one of claims 2 to 9,

the semiconductor element includes a main surface electrode formed on a main surface of the element,

the conductive member includes a lead wire which is bonded to the main surface electrode and the lead wire and electrically connects the main surface electrode and the lead wire,

the resin composition includes a lead-side covering portion covering a bonding portion between the lead and the lead.

11. The semiconductor device according to claim 10,

the lead includes a first bonding portion bonded to the main surface electrode and a second bonding portion bonded to the wire,

the wire-side covering portion includes a wire-side first portion interposed between the second joint portion and the sealing resin.

12. The semiconductor device according to claim 11,

the lead-side covering portion further includes a lead-side second portion that is continuous with the lead-side first portion and is interposed between the lead and the sealing resin.

13. The semiconductor device according to claim 11 or 12,

the lead further includes a linear portion connecting the first bonding portion and the second bonding portion,

the linear portion includes a resin contact region that is in contact with the sealing resin over the entire circumferential periphery.

14. The semiconductor device according to any one of claims 1 to 13,

the semiconductor element is a power semiconductor chip.

15. A method for manufacturing a semiconductor device, comprising:

preparing a lead frame;

preparing a semiconductor element having an element principal surface and an element back surface separated from each other in a first direction;

a component mounting step of mounting the semiconductor component on the lead frame;

a conductive member forming step of bonding a conductive member to the lead frame and the semiconductor element and making the lead frame and the semiconductor element conductive via the conductive member;

a coating step of coating a paste composition so as to cover a bonding portion between the conductive member and the lead frame and expose a part of a main surface of the element;

drying the applied paste composition; and

a step of forming a sealing resin which covers a part of the lead frame, the semiconductor element, and the dried paste composition,

the paste composition contains a resin material, the bonding strength of the resin material to the lead frame is superior to the bonding strength of the sealing resin to the lead frame, and the bonding strength of the resin material to the conductive member is superior to the bonding strength of the sealing resin to the conductive member.

16. The method for manufacturing a semiconductor device according to claim 15,

the lead frame includes: a chip pad having a pad main surface facing the same direction as the element main surface and a pad back surface facing the same direction as the element back surface; and a wire separated from the chip bonding pad,

in the device mounting step, the semiconductor device is mounted on the die pad in a posture in which the pad main surface faces the device back surface.

17. The method for manufacturing a semiconductor device according to claim 16,

the semiconductor device includes a back electrode formed on a back surface of the device,

in the conductive member forming step, before the element mounting step, a conductive paste for bonding the back surface electrode and the die pad is applied, and after the element mounting step, the conductive paste is dried to form a conductive bonding material for bonding the semiconductor element and the die pad and for electrically connecting the back surface electrode and the die pad,

in the coating step, the paste composition is coated so as to cover at least a bonding portion of the conductive bonding material and the die pad.

18. The method for manufacturing a semiconductor device according to claim 16,

the semiconductor element includes a main surface electrode formed on a main surface of the element,

in the conductive member forming step, a lead wire is formed after the element mounting step, the lead wire being bonded to the main surface electrode and the lead wire and electrically connecting the main surface electrode and the lead wire,

in the coating step, the paste composition is applied so as to cover at least a bonding portion between the lead and the wire.

Technical Field

The present disclosure relates to a semiconductor device and a method of manufacturing the semiconductor device.

Background

Patent document 1 discloses a conventional semiconductor device. The semiconductor device described in patent document 1 includes a semiconductor element, a lead frame, solder, a lead, and a sealing resin. In the Semiconductor device, the Semiconductor element is, for example, a diode chip or a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) chip. The lead frame carries the semiconductor element and is electrically connected to the semiconductor element via solder and a lead. The solder and the lead are conducting members for conducting the lead frame and the semiconductor element. The solder is interposed between the semiconductor element and the lead frame and makes them conductive. The leads are bonded to the semiconductor element and the lead frame and electrically connected thereto. The sealing resin covers a part of the lead frame, the semiconductor element, the solder, and the lead.

Documents of the prior art

Patent document

Patent document 1 Japanese patent laid-open publication No. 2017-5165

Disclosure of Invention

Problems to be solved by the invention

A semiconductor device is subjected to a thermal load due to, for example, a reflow when mounted on a circuit board of an electronic device or the like, or heat generated from a semiconductor element during operation. The thermal load causes thermal stress to concentrate at a joint portion between a conductive member such as solder or a lead and a lead frame. The thermal stress may concentrate to cause peeling of the sealing resin at the interface between the bonding portion and the sealing resin. When the sealing resin is peeled off, a thermal load is applied again, and thus, for example, a crack may be generated in the solder serving as the conductive member. Further, the lead wire as the conductive member may be detached or broken. These conditions can lead to failure of the semiconductor device.

The present disclosure has been made in view of the above problems, and an object thereof is to provide a semiconductor device and a method for manufacturing the semiconductor device, which can suppress a failure by suppressing peeling of a sealing resin due to a thermal load.

Means for solving the problems

A first aspect of the present disclosure provides a semiconductor device including: a semiconductor element having an element principal surface and an element back surface separated from each other in a first direction; a lead frame on which the semiconductor element is mounted; a conducting member which is joined to the lead frame and conducts the semiconductor element to the lead frame; a resin composition covering a joint portion between the conductive member and the lead frame and exposing a portion of a main surface of the element; and a sealing resin covering a part of the lead frame, the semiconductor element, and the resin composition, wherein the bonding strength between the resin composition and the lead frame is higher than the bonding strength between the sealing resin and the lead frame, and the bonding strength between the resin composition and the conductive member is higher than the bonding strength between the sealing resin and the conductive member.

In a preferred embodiment of the semiconductor device, the lead frame includes: a chip pad having a pad main surface facing the same direction as the element main surface and a pad back surface facing the same direction as the element back surface; and a lead separated from the die pad, wherein the semiconductor device is mounted on the die pad such that the pad main surface faces the device back surface.

In a preferred embodiment of the semiconductor device, the semiconductor element includes a back surface electrode formed on a back surface of the element, the conductive member includes a conductive bonding material for bonding the semiconductor element to the die pad and electrically connecting the back surface electrode to the die pad, and the resin composition includes a die pad side covering portion covering a bonding portion between the conductive bonding material and the die pad.

In a preferred embodiment of the semiconductor device, the conductive bonding material includes: the conductive bonding material includes: an element contact surface that contacts the back surface electrode; a chip bonding pad contact surface contacting with the chip bonding pad; and a connecting surface connected to the element contact surface and the die pad contact surface, wherein the die pad side covering portion includes a die pad side first portion interposed between the connecting surface and the sealing resin.

In a preferred embodiment of the semiconductor device, the die pad-side covering portion further includes a die pad-side second portion which is continuous with the die pad-side first portion and is interposed between the pad main surface and the sealing resin.

In a preferred embodiment of the semiconductor device, the semiconductor element has an element side surface which is continuous with the element main surface and the element back surface, and the die pad-side covering portion further includes a die pad-side third portion which is continuous with the die pad-side first portion and is interposed between at least a part of the element side surface and the sealing resin.

In a preferred embodiment of the semiconductor device, the die pad-side covering portion further includes a die pad-side fourth portion which is continuous with the die pad-side third portion and is interposed between a part of the element main surface and the sealing resin.

In a preferred embodiment of the semiconductor device, the conductive bonding material is solder.

In a preferred embodiment of the semiconductor device, the back surface of the pad is exposed from the sealing resin.

In a preferred embodiment of the semiconductor device, the semiconductor element includes a main surface electrode formed on a main surface of the element, the conductive member includes a lead wire which is bonded to the main surface electrode and the lead wire and electrically connects the main surface electrode and the lead wire, and the resin composition includes a lead wire side coating portion which covers a bonding portion between the lead wire and the lead wire.

In a preferred embodiment of the semiconductor device, the lead includes a first bonding portion bonded to the principal surface electrode and a second bonding portion bonded to the lead, and the lead-side covering portion includes a lead-side first portion interposed between the second bonding portion and the sealing resin.

In a preferred embodiment of the semiconductor device, the lead-side covering portion further includes a lead-side second portion that is continuous with the lead-side first portion and is interposed between the lead and the sealing resin.

In a preferred embodiment of the semiconductor device, the lead further includes a linear portion connecting the first bonding portion and the second bonding portion, and the linear portion includes a resin contact region that is in contact with the sealing resin over an entire circumference in a circumferential direction.

In a preferred embodiment of the semiconductor device, the semiconductor element is a power semiconductor chip.

A second aspect of the present disclosure provides a method for manufacturing a semiconductor device, including: preparing a lead frame; preparing a semiconductor element having an element principal surface and an element back surface separated from each other in a first direction; a component mounting step of mounting the semiconductor component on the lead frame; a conductive member forming step of bonding a conductive member to the lead frame and the semiconductor element and making the lead frame and the semiconductor element conductive via the conductive member; a coating step of coating a paste composition so as to cover a bonding portion between the conductive member and the lead frame and expose a part of a main surface of the element; drying the applied paste composition; and forming a sealing resin which covers a part of the lead frame, the semiconductor element, and the dried paste composition, wherein the paste composition contains a resin material, the bonding strength between the resin material and the lead frame is higher than the bonding strength between the sealing resin and the lead frame, and the bonding strength between the resin material and the conductive member is higher than the bonding strength between the sealing resin and the conductive member.

In a preferred embodiment of the method for manufacturing a semiconductor device, the lead frame includes: a chip pad having a pad main surface facing the same direction as the element main surface and a pad back surface facing the same direction as the element back surface; and a lead separated from the die pad, wherein in the element mounting step, the semiconductor element is mounted on the die pad in a posture in which the pad main surface faces the element rear surface.

In a preferred embodiment of the method for manufacturing a semiconductor device, the semiconductor element includes a back surface electrode formed on a back surface of the element, the conductive member forming step applies a conductive paste for bonding the back surface electrode to the die pad before the element mounting step, and after the element mounting step, the conductive paste is dried to form a conductive bonding material for bonding the semiconductor element to the die pad and electrically connecting the back surface electrode to the die pad, and the applying step applies the composition so as to cover at least a bonding portion of the conductive bonding material and the die pad.

In a preferred embodiment of the method for manufacturing a semiconductor device, the semiconductor element includes a main surface electrode formed on a main surface of the element, the conductive member forming step forms a lead wire which is bonded to the main surface electrode and the wire and which electrically connects the main surface electrode and the wire, after the element mounting step, and the paste composition is applied so as to cover at least a bonding portion of the lead wire and the wire in the applying step.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the semiconductor device of the present disclosure, peeling of the sealing resin due to a thermal load can be suppressed, thereby suppressing a failure. In addition, according to the manufacturing method of the present disclosure, a semiconductor device in which malfunction can be suppressed can be manufactured.

Drawings

Fig. 1 is a perspective view showing a semiconductor device according to a first embodiment.

Fig. 2 is a perspective view of fig. 1, with the sealing resin and the resin composition omitted.

Fig. 3 is a plan view showing the semiconductor device according to the first embodiment.

Fig. 4 is a plan view of fig. 3 with the sealing resin omitted.

Fig. 5 is a front view showing the semiconductor device of the first embodiment.

Fig. 6 is a bottom view showing the semiconductor device of the first embodiment.

Fig. 7 is a side view (right side view) showing the semiconductor device of the first embodiment.

Fig. 8 is a sectional view taken along line VIII-VIII of fig. 4.

Fig. 9 is a sectional view taken along line IX-IX of fig. 4.

Fig. 10 is a sectional view taken along line X-X of fig. 4.

Fig. 11 is a diagram showing a step in the method for manufacturing a semiconductor device according to the first embodiment.

Fig. 12 is a diagram showing a step in the method for manufacturing a semiconductor device according to the first embodiment.

Fig. 13 is a diagram showing a step in the method for manufacturing a semiconductor device according to the first embodiment.

Fig. 14A is a schematic cross-sectional view showing a case where a sealing resin is directly formed on a conductive bonding material.

Fig. 14B is a schematic cross-sectional view showing the case where the resin composition is interposed between the conductive bonding material and the sealing resin.

Fig. 15 is a plan view showing the semiconductor device according to the second embodiment (the sealing resin is omitted).

Fig. 16 is a cross-sectional view showing a semiconductor device according to a second embodiment.

Fig. 17 is a perspective view showing a semiconductor device according to a third embodiment.

Fig. 18 is a perspective view of the sealing resin and the resin composition omitted from the perspective view of fig. 17.

Fig. 19 is a plan view showing a semiconductor device according to a third embodiment.

Fig. 20 is a plan view of fig. 19 with the sealing resin omitted.

Fig. 21 is a front view showing a semiconductor device according to a third embodiment.

Fig. 22 is a bottom view showing a semiconductor device according to a third embodiment.

Fig. 23 is a sectional view taken along line XXIII-XXIII of fig. 20.

Fig. 24 is a sectional view taken along line XXIV-XXIV of fig. 20.

Fig. 25 is a plan view showing a semiconductor device according to a fourth embodiment.

Fig. 26 is a partially enlarged view of fig. 25.

Fig. 27 is a sectional view taken along line XXVII-XXVII of fig. 25.

Fig. 28 is a sectional view taken along line XXVIII-XXVIII of fig. 25.

Fig. 29 is a plan view showing a semiconductor device according to a fifth embodiment.

FIG. 30 is a cross-sectional view taken along line XXX-XXX in FIG. 29.

Fig. 31 is a cross-sectional view taken along line XXXI-XXXI of fig. 29.

Detailed Description

Preferred embodiments of the semiconductor device and the method for manufacturing the same according to the present disclosure will be described below with reference to the drawings.

Fig. 1 to 10 show a semiconductor device according to a first embodiment of the present disclosure. The semiconductor device a1 of the first embodiment includes a semiconductor element 1, a lead frame 2, a plurality of leads 3, a conductive bonding material 4, a sealing resin 5, and a resin composition 6. The plurality of leads 3 include a plurality of first leads 31, second leads 32, and third leads 33.

Fig. 1 is a perspective view showing a semiconductor device a 1. Fig. 2 is a perspective view of fig. 1, with the sealing resin 5 and the resin composition 6 omitted. Fig. 3 is a plan view showing a semiconductor device a 1. Fig. 4 is a plan view of fig. 3 with the sealing resin 5 omitted. In fig. 4, the resin composition 6 is shown by a virtual line (a dot pattern is added for easy understanding). Fig. 5 is a front view showing a semiconductor device a 1. Fig. 6 is a bottom view of the semiconductor device a 1. Fig. 7 is a side view (right side view) showing a semiconductor device a 1. Fig. 8 is a sectional view taken along line VIII-VIII of fig. 4. Fig. 9 is a sectional view taken along line IX-IX of fig. 4. Fig. 10 is a sectional view taken along line X-X of fig. 4. For convenience of explanation, three directions orthogonal to each other are defined as an x direction, a y direction, and a z direction. The x direction is a horizontal direction in a plan view (see fig. 3 and 4). The y direction is a vertical direction in a plan view (see fig. 3 and 4). The z direction is a thickness (height) direction of the semiconductor device a 1.

The semiconductor element 1 is an electronic component that is a main function of the semiconductor device a1 and is made of a semiconductor material. As such a semiconductor material, there are Si (silicon), SiC (silicon carbide), GaAs (gallium arsenide), and the like, but not limited thereto. The semiconductor element 1 is a power semiconductor chip such as a MOSFET. In the present embodiment, the case where the semiconductor element 1 is a MOSFET is shown, but the present invention is not limited to this, and may be another Transistor such as an IGBT (Insulated Gate Bipolar Transistor), or a diode such as a schottky barrier diode or a fast recovery diode. In the present disclosure, the power semiconductor chip is defined, for example, for use in a case where the product of the voltage between the input terminal and the output terminal and the current flowing through the input terminal and the output terminal is substantially 1W or more. The input terminal and the output terminal are referred to as a drain electrode and a source electrode in the MOSFET, respectively. As shown in fig. 4, the semiconductor element 1 has a rectangular shape in plan view, for example. As shown in fig. 4, 8, and 9, the semiconductor element 1 has an element main surface 1a, an element rear surface 1b, and a plurality of element side surfaces 1 c.

The element principal surface 1a and the element back surface 1b are separated in the z direction and face opposite sides to each other. The plurality of element side surfaces 1c are sandwiched between the element main surface 1a and the element rear surface 1 b. One end edge in the z direction (upper edge in fig. 8 and 9) of each element side surface 1c is connected to the element main surface 1a, and the other end edge in the z direction (lower edge in fig. 8 and 9) is connected to the element rear surface 1 b. The element principal surface 1a, the element back surface 1b, and the plurality of element side surfaces 1c are all substantially flat. In the present embodiment, the semiconductor element 1 has a pair of element side surfaces 1c each facing the x direction and a pair of element side surfaces 1c each facing the y direction.

As shown in fig. 2, 4, 8, and 9, the semiconductor element 1 includes a plurality of main surface electrodes 11 and a plurality of rear surface electrodes 12. Therefore, the semiconductor element 1 has a vertical structure. The plurality of main surface electrodes 11 are formed on the element main surface 1 a. As shown in fig. 2 and 4, the plurality of main surface electrodes 11 include a first main surface electrode 111, a second main surface electrode 112, and a third main surface electrode 113. The back electrode 12 is formed on the element back surface 1 b. The first main surface electrode 111 is a source electrode, the second main surface electrode 112 is a gate electrode, the third main surface electrode 113 is a source sensing electrode, and the back surface electrode 12 is a drain electrode. The arrangement, size, and shape of the first principal surface electrode 111, the second principal surface electrode 112, and the third principal surface electrode 113 are not limited to those shown in the drawings. In addition, the third main surface electrode 113 (source sensing electrode) may not be formed. The constituent material of each of the plurality of main surface electrodes 11 (the first main surface electrode 111, the second main surface electrode 112, and the third main surface electrode 113) and the back surface electrode 12 is, for example, Al (aluminum).

The lead frame 2 carries the semiconductor element 1 and is electrically connected to the semiconductor element 1. The lead frame 2 is mounted on a circuit board of an electronic device or the like, and forms a conductive path between the semiconductor element 1 and the circuit board. The lead frame 2 is made of a conductive material. The conductive material is, for example, Cu (copper). The conductive material is not limited to Cu, but may be Ni (nickel), a Cu alloy, a Ni alloy, a 42 alloy, or the like. The lead frame 2 is formed from a metal plate of Cu or the like, which is rectangular in plan view, into an appropriate shape by punching, cutting, bending, or the like. As shown in fig. 2 and 4, the lead frame 2 includes a first lead 21, a second lead 22, a third lead 23, and a die pad 24. They are separated from each other in the lead frame 2.

The first lead 21 is a part of the lead frame 2 electrically connected to the first main surface electrode 111 (source electrode) of the semiconductor element 1. The first wire 21 is electrically connected to the first main surface electrode 111 via the first lead 31. As shown in fig. 2, 4 and 8, the first wire 21 includes a wire bonding portion 211 and a plurality of terminal portions 212.

The wire bonding portion 211 is joined to one end of each first wire 31. The wire bonding portion 211 is covered with a sealing resin 5.

The plurality of terminal portions 212 are connected to the wire bonding portions 211, respectively. A part of each terminal portion 212 is exposed from the sealing resin 5. The plurality of terminal portions 212 have the same shape except for one. Note that all of the plurality of terminal portions 212 of the first conductive line 21 may have the same shape. The plurality of terminal portions 212 overlap with each other as viewed in the y direction. Each terminal portion 212 is joined to the circuit board as a source terminal of the semiconductor device a 1. As shown in fig. 1 to 6, the first conductive wire 21 includes five terminal portions 212. Further, the number, length, and shape of the terminal portions 212 are not limited to the illustrated example.

The second lead 22 is a part of the lead frame 2 electrically connected to the second main surface electrode 112 (gate electrode) of the semiconductor element 1. The second wire 22 is electrically connected to the second main surface electrode 112 via the second lead 32. As shown in fig. 2 and 4, the second wire 22 includes a wire bonding portion 221 and a terminal portion 222.

One end of the second wire 32 is bonded to the wire bonding portion 221. The wire bonding portion 221 is covered with a sealing resin 5.

The terminal portion 222 is connected to the wire bonding portion 221. A part of the terminal portion 222 is exposed from the sealing resin 5. The terminal portion 222 is partially bent at a portion exposed from the sealing resin 5. The terminal portion 222 overlaps with the plurality of terminal portions 212 as viewed in the y direction. The terminal portion 222 is bonded to the circuit board as a gate terminal of the semiconductor device a 1.

The third lead 23 is a part of the lead frame 2 electrically connected to the third main surface electrode 113 (source sensing electrode) of the semiconductor element 1. The third wire 23 is electrically connected to the third main surface electrode 113 via the third lead 33. As shown in fig. 2 and 4, the third wire 23 includes a wire bonding portion 231 and a terminal portion 232.

The wire bonding portion 231 has one end to which the third wire 33 is bonded. The wire bonding portion 231 is covered with the sealing resin 5.

The terminal portion 232 is connected to the wire bonding portion 231. A part of the terminal portion 232 is exposed from the sealing resin 5. The terminal portion 232 is partially bent at a portion exposed from the sealing resin 5. The terminal portions 232 overlap with the plurality of terminal portions 212 and the terminal portions 222 as viewed in the y direction. Terminal portion 232 is sandwiched between a plurality of terminal portions 212 and terminal portion 222 in the x direction. The terminal portion 232 is bonded to the circuit substrate as a source sensing terminal in the semiconductor device a 1.

The die pad 24 is a part of the lead frame 2 on which the semiconductor element 1 is mounted. A part of the die pad 24 is covered with the sealing resin 5, and the other part is exposed from the sealing resin 5. As shown in fig. 8 and 9, the die pad 24 has a pad main surface 24a and a pad back surface 24 b.

The pad main surface 24a and the pad back surface 24b face opposite sides and are separated from each other in the z direction. The pad main surface 24a faces in the same direction as the element main surface 1 a. The pad main surface 24a faces the element rear surface 1 b. The pad back surface 24b faces the same direction as the element back surface 1 b. The pad back surface 24b is exposed from the sealing resin 5.

The die pad 24 is electrically connected to the back surface electrode 12 (drain electrode) via the conductive bonding material 4. The die pad 24 is bonded to the circuit substrate as a drain terminal in the semiconductor device a 1.

Each of the first, second, and third leads 31, 32, and 33 is a connecting member for electrically connecting the semiconductor element 1 to the lead frame 2.

The plurality of first leads 31 are bonding leads containing Al. The plurality of first leads 31 are, for example, Al alloy added with any of Fe (iron), Si, and Ni, or pure Al. In addition, each first lead 31 may beSo as to be a bonding wire containing Cu or Au (gold) instead of Al. Instead of the bonding wire, a bonding tape may be used for each first wire 31. In the present embodiment, the case where the semiconductor device a1 includes two first leads 31 is shown, but the number of the first leads 31 is not particularly limited. The wire diameter of each first lead 31 is, for exampleLeft and right. As shown in fig. 2, 4, and 8, each first lead 31 includes a first bonding portion 311, a second bonding portion 312, and a linear portion 313.

The first bonding portion 311 is one end of each first lead 31, and is a portion bonded to the first main surface electrode 111 of the semiconductor element 1. As shown in fig. 2, 4, and 8, the first joint portion 311 includes a front contact portion 311a, a rear contact portion 311b, and an intermediate portion 311 c. Both the front contact portion 311a and the rear contact portion 311b contact the first main surface electrode 111. The front contact portion 311a is located farther from the second joint portion 312, and the rear contact portion 311b is located closer to the second joint portion 312. The intermediate portion 311c is sandwiched between the front contact portion 311a and the rear contact portion 311 b. The intermediate portion 311c is not joined to the first main surface electrode 111, and has an arch shape slightly floating from the first main surface electrode 111. In the present embodiment, the first bonding portion 311 abuts against the first main surface electrode 111 at two locations (including the front abutting portion 311a and the rear abutting portion 311b), but may abut against the first main surface electrode 111 at one location.

The second bonding portion 312 is the other end of each first wire 31 and is a portion bonded to the wire bonding portion 211 of the first wire 21. The second bonding portion 312 is covered with the resin composition 6.

The linear portion 313 is a portion connecting the first joint portion 311 and the second joint portion 312, and extends from the first joint portion 311 and the second joint portion 312, respectively. The linear portion 313 has a circular cross section perpendicular to the longitudinal direction. The linear portion 313 includes a resin composition contact region 313a and a sealing resin contact region 313 b. The resin composition contact region 313a is covered with the resin composition 6. The resin composition abutment region 313a abuts the resin composition 6 over the entire circumference of the circumference thereof. The sealing resin contact region 313b is not covered with the resin composition 6 but is covered with the sealing resin 5. The sealing resin contact region 313b is in contact with the sealing resin 5 over the entire circumference in the circumferential direction.

Each first lead 31 electrically connects the first main surface electrode 111 and the first wire 21. In the semiconductor device a1, each of the first leads 31 and the first main surface electrode 111 is made of a metal containing Al. Therefore, the influence of thermal stress on their joining portions is small.

The second wire 32 is a bonding wire containing Au. The second wire 32 may be a bonding wire containing Al or Cu instead of Au. The wire diameter of the second lead 32 is smaller than that of the first lead 31. I.e. the second wire 32 is thinner than the first wire 31. The wire diameter of the second lead 32 is, for example, asLeft and right. The wire diameter of the second lead 32 may be appropriately changed depending on the constituent material of the second lead 32. As shown in fig. 4, the second lead 32 includes a first bonding portion 321, a second bonding portion 322, and a linear portion 323.

The first bonding portion 321 is one end of the second lead 32 and is a portion bonded to the second main surface electrode 112 of the semiconductor element 1.

The second bonding portion 322 is the other end of the second wire 32, and is a portion bonded to the wire bonding portion 221.

The linear portion 323 is a portion connecting the first joint portion 321 and the second joint portion 322, and extends from each of the first joint portion 321 and the second joint portion 322. The linear portion 313 has a circular cross section perpendicular to the longitudinal direction.

The second lead 32 electrically connects the second main surface electrode 112 and the second wire 22.

The third wire 33 is a bonding wire containing Au. The third wire 33 may be a bonding wire containing Al or Cu instead of Au. The third lead 33 is made of the same material and has the same wire diameter as the second lead 32, for example, but may be different. The wire diameter of the third lead 33 may be appropriately changed depending on the material constituting the third lead 33. As shown in fig. 4, the third lead 33 includes a first bonding portion 331, a second bonding portion 332, and a linear portion 333.

The first bonding portion 331 is one end of the third lead 33 and is a portion bonded to the third main surface electrode 113 of the semiconductor element 1. In the case where the third main surface electrode 113 (source sensing electrode) is not included in the main surface electrode 11, the source current can be detected by bonding the first bonding portion 331 to the first main surface electrode 111 (source electrode).

The second bonding portion 332 is the other end of the third wire 33 and is a portion bonded to the wire bonding portion 231.

The linear portion 333 is a portion connecting the first joining portion 331 and the second joining portion 332, and extends from each of the first joining portion 331 and the second joining portion 332. The linear portion 313 has a circular cross section perpendicular to the longitudinal direction.

The third lead 33 electrically connects the third main surface electrode 113 and the third wire 23.

The conductive bonding material 4 is used for bonding the semiconductor element 1 to the lead frame 2. As shown in fig. 8 and 9, the conductive bonding material 4 is interposed between the device back surface 1b of the semiconductor device 1 and the pad main surface 24a of the die pad 24, and electrically connects the back surface electrode 12 of the semiconductor device 1 and the die pad 24. The conductive bonding material 4 is, for example, solder. The material of the solder is not particularly limited, and examples thereof include a lead-free solder such as a Sn-Sb alloy or a Sn-Ag alloy, and a lead-containing solder such as a Sn-Pb alloy.

As shown in fig. 8 and 9, the conductive bonding material 4 has an element contact surface 4a, a die pad contact surface 4b, and a connection surface 4 c. The element contact surface 4a is a surface that contacts the element back surface 1b of the semiconductor element 1. The element abutment surface 4a is, for example, substantially flat. The die pad contact surface 4b is a surface that contacts the pad main surface 24a of the die pad 24. The die pad contact surface 4b is, for example, substantially flat. The contact surface 4c is a surface which is sandwiched between and connects the element contact surface 4a and the die pad contact surface 4 b. The connecting surface 4c may be substantially flat or curved. As shown in fig. 8 and 9, the contact surface 4c is inclined with respect to the element contact surface 4a and the die pad contact surface 4 b. The angle formed by the element contact surface 4a and the connection surface 4c is, for example, about 0.3 to 27 °. The z-direction dimension (thickness) Δ H (see fig. 9) of the conductive bonding material 4 is, for example, about 10 to 150 μm, and the projecting dimension Δ L (see fig. 9) of the conductive bonding material 4 projecting outward from each element side surface 1c in a plan view is, for example, about 300 to 2000 μm. The angle and the dimensions Δ H and Δ L are values in consideration of manufacturing errors, and are values in the manufactured semiconductor device a 1. The angle is, for example, about 1 to 15 DEG, the z-direction dimension Δ H of the conductive bonding material 4 is, for example, about 30 to 130 μm, and the respective projecting dimensions Δ L of the conductive bonding material 4 are, for example, about 500 to 1500 μm, as design values at the time of production.

The sealing resin 5 covers the semiconductor element 1, a part of the lead frame 2, the plurality of leads 3, and the resin composition 6. The sealing resin 5 is a thermosetting synthetic resin having electrical insulation properties. The sealing resin 5 is, for example, a black epoxy resin, and a filler is mixed therein. The filler is, for example, spherical and has a particle diameter of, for example, about 75 μm. As shown in fig. 1, 3, and 5 to 10, the sealing resin 5 has a resin main surface 5a, a resin rear surface 5b, and a plurality of resin side surfaces 5 c.

The resin main surface 5a and the resin rear surface 5b face opposite sides and are separated from each other in the z direction. The resin main surface 5a faces in the same direction as the element main surface 1a, and the resin rear surface 5b faces in the same direction as the element rear surface 1 b. Each of the plurality of resin side surfaces 5c is sandwiched between the resin main surface 5a and the resin back surface 5 b. One end edge in the z direction of each resin side surface 5c is connected to the resin main surface 5a, and the other end edge in the z direction of each resin side surface 5c is connected to the resin back surface 5 b. In the present embodiment, the sealing resin 5 has a pair of resin side surfaces 5c separated in the x direction and a pair of resin side surfaces 5c separated in the y direction.

In the present embodiment, the first lead 21, the second lead 22, and the third lead 23 protrude from the resin side surface 5 c. In addition, a part of the die pad 24 protrudes from the resin side surface 5 c. In addition, the first wire 21, the second wire 22, the third wire 23, and the die pad 24 sandwich the sealing resin 5 in a plan view, and protrude from the resin side surfaces 5c located on the opposite sides from each other. Further, the pad back surface 24b of the die pad 24 is exposed from the resin back surface 5 b.

The resin composition 6 covers the bonding portion of the conductive bonding material 4 and the die pad 24 and the bonding portion of the first lead 31 and the first wire 21. The bonding strength between the resin composition 6 and the lead frame 2 is superior to the bonding strength between the sealing resin 5 and the lead frame 2. In addition, the bonding strength of the resin composition 6 and the conductive bonding material 4 is superior to the bonding strength of the sealing resin 5 and the conductive bonding material 4, and the bonding strength of the resin composition 6 and the plurality of leads 3 is superior to the bonding strength of the sealing resin 5 and the plurality of leads 3. The relative acceptability of the bonding strength is determined based on the pudding cup strength (unit: MPa), for example. The pudding cup strength represents the shear strength in a state where the resin material (the material of the resin composition 6 and the sealing resin 5) in the form of a pudding cup is brought into close contact with the bonding target (the material of the lead frame 2, the conductive bonding material 4, and the plurality of leads 3). The greater the pudding cup strength, the higher the bonding strength, and the smaller the pudding cup strength, the lower the bonding strength. The resin composition 6 is made of a material containing, for example, a thermoplastic resin, an epoxy resin, a coupling agent, a powdery inorganic filler, a powder having rubber elasticity, and the like. The thickness of the resin composition 6 is, for example, about 10 to 20 μm. Further, the raw material and thickness of the resin composition 6 are not limited to the above raw materials. As shown in fig. 4 and 8, the resin composition 6 includes a die pad side cover portion 61 and a lead side cover portion 62. The die pad side cover 61 and the lead side cover 62 are disposed apart from each other.

The die pad side covering portion 61 covers the bonding portion between the conductive bonding material 4 and the die pad 24. In the following description, this bonding portion is referred to as a die pad side bonding portion. As shown in fig. 4, 8 and 9, the wafer pad side cover portion 61 includes a wafer pad side first portion 611, a wafer pad side second portion 612 and a wafer pad side third portion 613. The wafer pad side first portion 611, the wafer pad side second portion 612, and the wafer pad side third portion 613 are integrally formed.

As shown in fig. 8, the die pad side first portion 611 is a portion interposed between the contact surface 4c of the conductive bonding material 4 and the sealing resin 5.

As shown in fig. 8, the die pad side second portion 612 is a portion interposed between the pad main surface 24a of the die pad 24 and the sealing resin 5. The wafer pad side second portion 612 is connected to the wafer pad side first portion 611. Specifically, the wafer pad side second portion 612 is connected to an edge of the wafer pad side first portion 611 below in the z direction. In the present embodiment, the die pad side second portion 612 covers at least a part of the pad main surface 24a that is not in contact with the die pad contact surface 4b of the conductive bonding material 4, but the die pad side second portion 612 may cover the entire pad main surface 24a that is not in contact with the die pad contact surface 4b of the conductive bonding material 4.

As shown in fig. 8, the third portion 613 on the wafer pad side is a portion interposed between each element side surface 1c of the semiconductor element 1 and the sealing resin 5. The wafer pad side third portion 613 is connected to the wafer pad side first portion 611. Specifically, the wafer pad side third portion 613 is connected to an edge of the wafer pad side first portion 611 above in the z direction. In the present embodiment, the third portion 613 on the wafer pad side is arranged below the element main surface 1a in the z direction when viewed in the x direction or the y direction.

The wire-side covering portion 62 covers the joint portion of the first lead 31 and the first wire 21. In the following description, this bonding portion is referred to as a wire-side bonding portion. As shown in fig. 4 and 8, the wire-side cover 62 includes a wire-side first portion 621, a wire-side second portion 622, and a wire-side third portion 623. The wire-side first portion 621, the wire-side second portion 622, and the wire-side third portion 623 are integrally formed.

As shown in fig. 8, the wire-side first portion 621 is a portion interposed between the second bonding portion 312 of the first lead 31 and the sealing resin 5.

As shown in fig. 8, the wire-side second portion 622 is a portion interposed between the wire bonding portion 211 of the first wire 21 and the sealing resin 5. The wire-side second portion 622 is connected to the wire-side first portion 621.

As shown in fig. 8, the wire-side third portion 623 is a portion interposed between a part of the linear portion 313 (resin composition contact region 313a) of the first lead 31 and the sealing resin 5. Specifically, the wire-side third portion 623 is formed on a portion of the linear portion 313 on the second engagement portion 312 side. The wire-side third portion 623 is connected to the wire-side first portion 621.

Next, a method for manufacturing the semiconductor device a1 will be described with reference to fig. 11 to 13. In fig. 11 to 13, the same reference numerals are given to the same or similar elements as those in fig. 1 to 10.

First, as shown in fig. 11, a lead frame 200 and a semiconductor element 1 are prepared. The lead frame 200 is prepared to include the first lead 21, the second lead 22, the third lead 23 and the die pad 24, and they are connected by the frame 201. The lead frame 200 is, for example, sized to manufacture a plurality of semiconductor devices a 1. The prepared semiconductor element 1 is a MOSFET having a vertical structure, but may have a horizontal structure. The semiconductor element 1 has a first main surface electrode 111, a second main surface electrode 112, and a third main surface electrode 113 formed on an element main surface 1a, and a back surface electrode 12 formed on an element back surface 1 b.

Next, as shown in fig. 12, the semiconductor element 1 is mounted on the die pad 24 via the conductive bonding material 4. In the step of mounting the semiconductor element 1 (element mounting step), a conductive paste is applied to the pad main surface 24a of the die pad 24. In the present embodiment, solder paste is used as the conductive paste. Then, the semiconductor element 1 is mounted on the applied conductive paste. At this time, the semiconductor element 1 is mounted in a posture in which the pad main surface 24a faces the element rear surface 1 b. Next, the conductive paste is fired. Thereby, the conductive bonding material 4 is formed and the semiconductor element 1 is mounted on the die pad 24. The conductive bonding material 4 electrically connects the lead frame 200 (die pad 24) and the semiconductor element 1 (back surface electrode 12).

Next, as shown in fig. 12, the plurality of first, second, and third leads 31, 32, and 33 are bonded to the semiconductor element 1 and the lead frame 200. A known wire bonder is used for bonding each of the wires 3. In this embodiment, the case of performing wedge bonding using a wedge tool is described, but the wedge bonding may be performed by ball bonding using a capillary. The first wire 31 is a bonding wire whose main component is Al. The second wire 32 and the third wire 33 are bonding wires whose main component is Au. One end of the first lead 31 is bonded to the first main surface electrode 111, and the other end of the first lead 31 is bonded to the wire bonding portion 211 of the first wire 21. Further, one end of the second lead 32 is bonded to the second main surface electrode 112, and the other end of the second lead 32 is bonded to the wire bonding portion 221 of the second wire 22. Further, one end of the third wire 33 is bonded to the third main surface electrode 113, and the other end of the third wire 33 is bonded to the wire bonding portion 231 of the third wire 23. The bonding order of the first wire 31, the second wire 32, and the third wire 33 is not particularly limited.

For example, the step of bonding the first lead 31 is performed as follows. First, the tip of the wedge is pressed against the first principal surface electrode 111 and ultrasonic vibration is applied. Thereby, one end of the first lead 31 is ultrasonically melted to the first main surface electrode 111, and the front contact portion 311a is formed. Then, the first lead 31 is drawn out from the tip of the wedge, the wedge is slightly moved, and the tip of the wedge is again pressed against the first main surface electrode 111 to apply ultrasonic vibration thereto. Thereby, the intermediate portion 311c and the rear contact portion 311b are formed, and the first joining portion 311 is formed. Next, the first lead wire 31 is drawn out from the front end of the wedge and the wedge is moved. Thereby, the linear portion 313 is formed. Next, the first lead 31 is pressed against the wire bonding portion 211 of the first wire 21, and ultrasonic vibration is applied. Thereby, the other end of the first wire 31 is ultrasonically melted to the wire bonding portion 211. Thereafter, the wedge is slightly moved and a cut is made in the first lead 31 by using the blade of the wedge tool. Then, the first lead 31 is separated from the wire bonding portion 211 together with the wedge, thereby cutting the first lead 31. Thereby, the second joint portion 312 is formed. As described above, one end (first bonding portion 311) of the first lead 31 is bonded to the first main surface electrode 111, the other end (second bonding portion 312) of the first lead 31 is bonded to the wire bonding portion 211, and the first main surface electrode 111 and the wire bonding portion 211 (first wire 21) are electrically connected by the first lead 31. The step of bonding the second and third leads 32 and 33 is substantially the same as the step of bonding the first lead 31.

Next, as shown in fig. 13, resin composition 6 was formed. In forming the resin composition 6, first, the paste composition is applied to the extent of forming the resin composition 6. The step of applying the paste composition (application step) is performed using, for example, a spray dispenser. Further, instead of using a spray dispenser, other coating methods such as spray coating and spin coating may be used, or screen printing may be used. In the present embodiment, the paste composition is applied to the surface of the conductive bonding material 4 around the semiconductor element 1 in a plan view. The paste composition contains at least a resin material and an organic solvent. The bonding strength of the resin material to the lead frame 200 is superior to the bonding strength of the sealing resin 5 to the lead frame 200. In addition, the bonding strength of the resin material to the plurality of leads 3 is superior to that of the sealing resin 5 to the plurality of leads 3, and the bonding strength of the resin material to the conductive bonding material 4 is superior to that of the sealing resin 5 to the conductive bonding material 4. The paste composition in the present embodiment is composed of a raw material containing, for example, a thermoplastic resin, an epoxy resin, a coupling agent, a powdery inorganic filler, a powder having rubber elasticity, an organic solvent, and the like. Next, the applied paste composition is dried to volatilize the organic solvent, thereby forming a cured resin composition 6.

Next, the sealing resin 5 is formed. The sealing resin 5 can be formed by, for example, molding using a metal mold. As the sealing resin 5, for example, an epoxy resin mixed with a particulate filler is used. After the sealing resin 5 is formed, the lead frame 200 is cut as appropriate, and the semiconductor elements 1 are singulated. Before and after the cutting of the lead frame 200, it is appropriate to: the lead frame 2 exposed from the sealing resin 5 is improved in bending strength, adhesiveness when mounted on a printed circuit board or the like is improved, exterior processing for rust prevention or the like, lead processing for bending the lead frame 2 exposed from the sealing resin 5 into a predetermined shape, marking processing for marking a company name, a product name, a lot number, or the like on the sealing resin 5, inspection grading processing for determining whether or not the product is acceptable, and the like. These processes may be appropriately performed in accordance with the specification of the final semiconductor device a 1.

Through the above-described steps, the semiconductor device a1 shown in fig. 1 to 10 is completed.

Next, the operation and effects of the semiconductor device a1 according to the first embodiment will be described.

The semiconductor device A1 includes a resin composition 6. The resin composition 6 covers the bonding portion (e.g., bonding portion on the die pad side or bonding portion on the lead wire side) of the lead frame 2 and the conductive member (e.g., the conductive bonding material 4 or the first lead 31). The bonding strength between the resin composition 6 and the lead frame 2 is superior to the bonding strength between the sealing resin 5 and the lead frame 2, and the bonding strength between the resin composition 6 and the conductive member is superior to the bonding strength between the sealing resin 5 and the conductive member. With this configuration, the resin composition 6 functions as an adhesive, and the bonding strength between the bonding portion and the sealing resin 5 can be improved. Therefore, even when a thermal load is applied to the semiconductor device a1, the above-described peeling between the bonded portion and the sealing resin 5 can be suppressed. This makes it possible to suppress the failure of the semiconductor device a1 due to the peeling of the sealing resin 5.

In the semiconductor device a1, the element principal surface 1a of the semiconductor element 1 is exposed from the resin composition 6. That is, the element main surface 1a is not covered with the resin composition 6. When the semiconductor device a1 operates, the element main surface 1a side of the semiconductor element 1 easily generates heat. If the element main surface 1a is covered with the resin composition 6, heat on the element main surface 1a side is likely to accumulate if the thermal conductivity of the resin composition 6 is lower than the thermal conductivity of the sealing resin 5. Therefore, the temperature difference at the interface between the resin composition 6 and the element main surface 1a becomes large. The thermal stress caused by this temperature difference may cause the semiconductor device a1 to malfunction. Therefore, in the case where the thermal conductivity of the resin composition 6 is lower than the thermal conductivity of the sealing resin 5, the temperature difference at the interface of the element main surfaces 1a can be reduced by exposing the element main surfaces 1a from the resin composition 6 as compared with the case where the element main surfaces 1a are covered with the resin composition 6. This makes it possible to suppress the semiconductor device a1 from malfunctioning due to the temperature difference.

According to the manufacturing method of the semiconductor device a1, the paste composition is applied by a spray dispenser. Thereby, the paste composition can be selectively applied, and the resin composition 6 can be selectively formed. As shown in fig. 13, when the paste composition is applied, the application to the element main surface 1a of the semiconductor element 1 can be avoided, and the element main surface 1a can be prevented from being covered with the resin composition 6 formed as shown in fig. 4. Therefore, the semiconductor device a1 in which the above-described failure due to the temperature difference can be suppressed can be manufactured.

According to the semiconductor device a1, the resin composition 6 includes the die pad side covering portion 61, and the die pad side covering portion 61 covers the bonding portion (die pad side bonding portion) of the conductive bonding material 4 and the lead frame 2 (die pad 24). With this configuration, the die pad side coating portion 61 can improve the bonding strength between the die pad side bonding portion and the sealing resin 5, and suppress peeling between the die pad side bonding portion and the sealing resin 5. If such peeling occurs, when a thermal load is applied to the semiconductor device a1, thermal stress acting on the conductive bonding material 4 increases, and there is a possibility that cracks may occur in the conductive bonding material 4. The cracks lower the heat dissipation and electrical conductivity of the conductive bonding material 4. However, since the semiconductor device a1 can suppress peeling between the die pad side bonding portion and the sealing resin 5, it is possible to alleviate the thermal stress acting on the conductive bonding material 4 and suppress the occurrence of cracks in the conductive bonding material 4. Therefore, the semiconductor device a1 can suppress the heat dissipation and the decrease in the electrical conductivity of the conductive bonding material 4 by suppressing the cracking of the conductive bonding material 4. In addition, it is well known that leaded solders have a higher physical strength to thermal stress than lead-free solders. Therefore, in the conventional semiconductor device, in order to improve the resistance to thermal cycling, a lead-containing solder tends to be used for the conductive bonding material 4. On the other hand, in the semiconductor device a1, since the thermal stress acting on the conductive bonding material 4 can be relaxed by the wafer pad-side covering portion 61 (resin composition 6) as described above, the resistance to thermal cycles can be improved even when lead-free solder is used for the conductive bonding material 4. Therefore, the semiconductor device a1 can improve the resistance to thermal cycling in an environmentally friendly manner.

According to the semiconductor device a1, the die pad side covering portion 61 includes the die pad side first portion 611, and the die pad side first portion 611 is interposed between the connecting surface 4c of the conductive bonding material 4 and the sealing resin 5. With this configuration, the bonding strength between the conductive bonding material 4 and the sealing resin 5 can be improved by the die pad side first portion 611.

Fig. 14A and 14B are schematic views for explaining a mechanism for improving the bonding strength between the conductive bonding material 4 and the sealing resin 5 by the resin composition 6 (the die pad side first portion 611). Fig. 14A shows a conventional semiconductor device in which the sealing resin 5 is directly formed on the conductive bonding material 4, and fig. 14B shows a semiconductor device a1 of the present disclosure in which the resin composition 6 is interposed between the conductive bonding material 4 and the sealing resin 5.

As shown in fig. 14A, the surface of the conductive bonding material 4 is roughened by the fine grooves 40. The groove 40 has a particle diameter smaller than that of the filler 51 mixed into the sealing resin 5. Therefore, when the sealing resin 5 is directly formed on the surface of the conductive bonding material 4, the filler 51 mixed into the sealing resin 5 may block the opening of the groove 40, and the groove 40 may not be filled with the sealing resin 5. In this way, since the groove 40 of the sealing resin 5 cannot be filled, a void is generated at the interface between the conductive bonding material 4 and the sealing resin 5, and the bonding strength is reduced due to the void.

On the other hand, as shown in fig. 14B, the resin composition 6 is interposed between the conductive bonding material 4 and the sealing resin 5, and the groove 40 on the surface of the conductive bonding material 4 is filled with the resin composition 6. Therefore, the generation of voids can be suppressed by the resin composition 6, and the decrease in bonding strength due to the voids can be suppressed. Further, by filling the groove 40 with the resin composition 6, the bonding strength with the conductive bonding material 4 can be improved by the anchor effect. Hydrogen bonds are formed at the interface between the resin composition 6 and the sealing resin 5, and the bonding strength between the resin composition 6 and the sealing resin 5 is improved by the hydrogen bonds. For this reason, the resin composition 6 is interposed between the conductive bonding material 4 and the sealing resin 5, and thus the bonding strength between the conductive bonding material 4 and the sealing resin 5 can be improved.

According to the semiconductor device a1, the die pad-side covering portion 61 includes the die pad-side second portion 612, and the die pad-side second portion 612 is interposed between the pad main surface 24a of the die pad 24 and the sealing resin 5. With this structure, the bonding strength between the die pad 24 and the sealing resin 5 can be improved by the die pad side second portion 612. The surface of the lead frame 2 also has fine grooves, as in the case of the conductive bonding material 4. Therefore, the bonding strength between the die pad 24 and the sealing resin 5 can be improved in the same manner as the principle shown in fig. 14A and 14B.

According to the semiconductor device a1, the die pad side covering portion 61 includes the die pad side third portion 613, and the die pad side third portion 613 is interposed between the element side surface 1c and the sealing resin 5. With this structure, the bonding strength between the element side surface 1c and the sealing resin 5 can be improved by the third portion 613 on the wafer pad side. The element side surface 1c also has a fine groove, similarly to the conductive bonding material 4. Therefore, the bonding strength between the element side surface 1c and the sealing resin 5 is improved in the same manner as the principle shown in fig. 14A and 14B.

According to the semiconductor device a1, the resin composition 6 includes the wire-side covering portion 62, and the wire-side covering portion 62 covers the bonding portion (wire-side bonding portion) of each first lead 31 (each second bonding portion 312) and the lead frame 2 (the wire bonding portion 211 of the first lead 21). With this configuration, the lead-wire-side covering portion 62 can improve the bonding strength between the lead-wire-side bonded portion and the sealing resin 5, and can suppress the peeling between the lead-wire-side bonded portion and the sealing resin 5. If such peeling occurs, when a thermal load is applied to the semiconductor device a1, thermal stress acting on the second bonding portion 312 of each first lead 31 increases, and there is a possibility that each first lead 31 may be detached from the wire bonding portion 211. However, since the semiconductor device a1 can suppress peeling of the wire-side bonding portion from the sealing resin 5, thermal stress acting on the second bonding portion 312 of each first lead 31 can be relaxed, and detachment of each first lead 31 from the wire bonding portion 211 can be suppressed. In addition, in the case where each first lead 31 is made of a metal containing Al, a passive film (oxide film) is formed on the surface of each first lead 31 to protect it from corrosion, but when the bonding portion on the wire side and the sealing resin 5 are peeled off, the passive film on the surface of each first lead 31 may be broken by the mutual friction between each first lead 31 and the sealing resin 5. At this time, corrosion (e.g., pitting corrosion) progresses from the portion where the passive film is broken, resulting in a decrease in the conductivity of each first lead 31 or a disconnection of each first lead 31. On the other hand, in the semiconductor device a1, the lead-side cover 62 is used as a protective material to suppress corrosion of the first lead 31, thereby suppressing a decrease in the conductivity of the first lead 31 and disconnection of the first lead 31.

According to the semiconductor device a1, the lead-wire-side covering portion 62 includes the lead-wire-side first portion 621, and the lead-wire-side first portion 621 is interposed between the second bonding portion 312 of the first lead 31 and the sealing resin 5. With this configuration, the bonding strength between the second bonding portion 312 and the sealing resin 5 can be improved by the wire-side first portion 621.

According to the semiconductor device a1, the wire-side cover 62 includes the wire-side second portion 622, and the wire-side second portion 622 is interposed between the wire bonding portion 211 (the first wire 21) and the sealing resin 5. With this configuration, the bonding strength between the wire bonding portion 211 (first wire 21) and the sealing resin 5 can be improved by the wire-side second portion 622. The surface of the lead frame 2 (first lead 21) also has fine grooves, similarly to the conductive bonding material 4. Therefore, the bonding strength between the wire bonding portion 211 and the sealing resin 5 is improved in the same manner as the principle shown in fig. 14A and 14B.

According to the semiconductor device a1, the lead-side covering portion 62 includes the lead-side third portion 623, and the lead-side third portion 623 is interposed between a part of the linear portion 313 of the first lead 31 and the sealing resin 5. With this configuration, the bonding strength between the linear portion 313 of the first lead 31 and the sealing resin 5 can be improved by the wire-side third portion 623.

According to the semiconductor device a1, each first lead 31 is made of a metal containing Al, and the first lead 21 is made of a metal containing Cu. Each first lead 31 is joined to the first wire 21 (wire bonding portion 211). In the case where such bonding is performed by using different metals, thermal stress acting on each first lead 31 (second bonding portion 312) is increased by a difference in thermal expansion coefficient (linear expansion coefficient) as compared with the case where bonding is performed by using the same metal, and peeling between the bonding portion on the lead wire side and the sealing resin 5 is likely to occur. Therefore, in the case where the first leads 31 and the first lead wires 21 are made of different metals, the resin composition 6 includes the lead-side coating portion 62, so that the peeling of the lead-side bonding portion from the sealing resin 5 can be more effectively suppressed than in the case where the first leads 31 and the first lead wires 21 are made of the same metal.

According to the semiconductor device a1, the pad back surface 24b of the die pad 24 is exposed from the sealing resin 5. As described above, when the die pad 24 is exposed from the sealing resin 5, the expansion rate by the thermal load is larger than when it is not exposed. As a result, thermal stress at the bonding portion on the die pad side becomes large, and the sealing resin 5 is likely to peel off at the bonding portion on the die pad side. Therefore, in the semiconductor device a1 in which the pad back surface 24b of the die pad 24 is exposed from the sealing resin 5, the die pad side coating portion 61 is provided, thereby more effectively suppressing peeling of the sealing resin 5 due to thermal stress at the die pad side bonding portion.

According to the semiconductor device a1, the semiconductor element 1 is a power semiconductor chip such as a MOSFET. The power semiconductor chip has high resistance to a large current and voltage, but generates a large amount of heat. Therefore, the sealing resin 5 is likely to be peeled off. Therefore, in the semiconductor device a1 in which the power semiconductor chip is mounted as the semiconductor element 1, the peeling of the sealing resin 5 is more effectively suppressed by providing the resin composition 6.

In the first embodiment, the case where the resin composition 6 includes both the die pad side cover 61 and the lead side cover 62 is shown, but only one of them may be included. For example, in the case where the resin composition 6 includes only the die-pad-side covering portion 61, the bonding strength between the die-pad-side bonding portion and the sealing resin 5 can be improved by interposing the resin composition 6 (the die-pad-side covering portion 61) between the die-pad-side bonding portion and the sealing resin 5. In this case, the step of applying the paste composition (coating step) may be performed before the step of bonding the plurality of first, second, and third leads 31, 32, and 33. On the other hand, in the case where the resin composition 6 includes only the lead-side covering portion 62, the bonding strength between the lead-side bonding portion and the sealing resin 5 can be improved by interposing the resin composition 6 (the lead-side covering portion 62) between the lead-side bonding portion and the sealing resin 5. Therefore, when the resin composition 6 including only one of the die pad side coating portion 61 and the lead side coating portion 62 is formed, it is not necessary to form the other, and thus the cost can be reduced and the manufacturing process can be shortened.

In the first embodiment, the case where the wire-side covering portion 62 of the resin composition 6 covers the joint portion of the first lead 31 and the first lead 21 is shown, but the present invention is not limited to this. For example, instead of the lead-side covering portion 62, the resin composition 6 covering the joint portion between the second lead 32 and the second lead 22 may be provided, or the resin composition 6 covering the joint portion between the second lead 32 and the second lead 22 may be provided in addition to the lead-side covering portion 62. With this configuration, the sealing resin 5 can be prevented from peeling off from the bonded portion between the second lead 32 and the second lead 22. Further, instead of the wire-side covering portion 62, the resin composition 6 covering the joint portion of the third lead 33 and the third lead 23 may be provided, or the resin composition 6 covering the joint portion of the third lead 33 and the third lead 23 may be provided in addition to the wire-side covering portion 62. With this configuration, the sealing resin 5 can be prevented from peeling off from the bonding portion between the third lead 33 and the third lead 23.

Fig. 15 to 31 show other embodiments of the semiconductor device and the method for manufacturing the same of the present disclosure. In these drawings, the same or similar elements as those of the semiconductor device a1 of the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

Fig. 15 and 16 show a semiconductor device of a second embodiment. The semiconductor device a2 of the second embodiment is different from the semiconductor device a1 in the formation region of the resin composition 6. Specifically, as shown in fig. 15 and 16, the die pad side cover portion 61 of the resin composition 6 of the semiconductor device a2 further includes a die pad side fourth portion 614. Fig. 15 is a plan view showing a semiconductor device a2, and corresponds to fig. 4 in the first embodiment. Fig. 16 is a sectional view taken along line XVI-XVI shown in fig. 15.

As shown in fig. 15 and 16, the wafer pad side fourth portion 614 covers a part of the element main surface 1 a. The fourth portion 614 on the die pad side is interposed between a part of the element main surface 1a and the sealing resin 5. As shown in fig. 15 and 16, the wafer pad side fourth portion 614 is connected to the wafer pad side third portion 613. In the manufacturing process (coating process) of the semiconductor device a2, a paste composition to be the resin composition 6 is applied by, for example, a spray dispenser. When the paste composition is applied, a part of the paste composition may be formed on the element main surface 1 a. The fourth wafer pad side portion 614 may be formed of a part of the paste composition applied to the element main surface 1 a.

The semiconductor device a2 was provided with the resin composition 6 in the same manner as the semiconductor device a 1. The resin composition 6 covers the bonding portion (die pad side bonding portion or lead side bonding portion) of the lead frame 2 and the conductive member (e.g., the conductive bonding material 4 or the first lead 31). Therefore, in the semiconductor device a2, as in the semiconductor device a1, it is possible to suppress a failure due to peeling of the sealing resin 5.

In the second embodiment, the case where the first bonding portion 311 of each first lead 31, the first bonding portion 321 of the second lead 32, and the first bonding portion 331 of the third lead 33 are exposed from the die-pad-side cover portion 61 (resin composition 6) is shown, but the present invention is not limited thereto. For example, the die pad side coating portion 61 (resin composition 6) may cover a part or all of them. However, the first leads 31 tend to have a higher temperature than the second leads 32 and the third leads 33 because the source current flows therethrough. Therefore, each of the first leads 31 is more susceptible to adverse effects of a thermal load than the second lead 32 and the third lead 33. Therefore, it is preferable to expose at least the first bonding portion 331 of each first lead 31 from the die pad side covering portion 61 (resin composition 6) to suppress adverse effects of thermal load on each first lead 31.

In the second embodiment, the case where the wafer pad side fourth portion 614 covers a part of the element main surface 1a is shown, but is not limited thereto. For example, the wafer pad side fourth portion 614 may cover the entire element main surface 1 a. However, considering that the temperature difference at the interface of the element main surface 1a is large when the wafer pad side fourth portion 614 covers the entire element main surface 1a as described above, it is preferable that the wafer pad side fourth portion 614 covers not the entire element main surface 1a but only a part of the element main surface 1 a.

Fig. 17 to 24 show a semiconductor device according to a third embodiment. The semiconductor device A3 of the third embodiment is different from the semiconductor device a1 mainly in that it does not include a source sense terminal.

Fig. 17 is a perspective view showing a semiconductor device a 3. Fig. 18 is a perspective view of fig. 17, in which the sealing resin 5 and the resin composition 6 are omitted. Fig. 19 is a plan view showing a semiconductor device a 3. Fig. 20 is a plan view of fig. 19 with the sealing resin 5 omitted. In fig. 20, the resin composition 6 is shown by a virtual line (dot pattern is added for easy understanding). Fig. 21 is a front view showing a semiconductor device a 3. Fig. 22 is a bottom view of the semiconductor device a 3. Fig. 23 is a sectional view taken along line XXIII-XXIII of fig. 20. Fig. 24 is a sectional view taken along line XXIV-XXIV of fig. 20.

As shown in fig. 18, 20, and 24, in the semiconductor device a3, the semiconductor element 1 includes the first main surface electrode 111 and the second main surface electrode 112 as the main surface electrode 11. Therefore, the semiconductor element 1 of the present embodiment does not include the third main surface electrode 113, as compared with the semiconductor element 1 of the first embodiment. Therefore, the semiconductor device a3 does not include the third lead 33 and the third wire 23 provided for electrically connecting the third main surface electrode 113 to the outside of the semiconductor device.

In the semiconductor device a3, the first conductive wire 21 includes one terminal portion 212 instead of the plurality of terminal portions 212. In the semiconductor device a3, the number of the terminal portions 212 is not limited. As shown in fig. 17 to 22, in the semiconductor device a3, the die pad 24 includes a portion protruding from the sealing resin 5 between the terminal portion 212 and the terminal portion 222. The protruding portion may be shorter than each of the terminal portions 212 and 222 as shown in fig. 17 to 22, or may not be the same shape as each of the terminal portions 212 and 222.

According to the semiconductor device a3, the bonding portion (die pad side bonding portion or lead wire side bonding portion) of the conductive member (conductive bonding material 4 or first lead 31) and the lead frame 2 is covered with the resin composition 6. Therefore, in the semiconductor device A3, as in the semiconductor device a1, it is possible to suppress a failure due to peeling of the sealing resin 5.

Fig. 25 to 28 show a semiconductor device according to a fourth embodiment. The semiconductor device a4 of the fourth embodiment is different from the semiconductor device a1 in the formation region of the resin composition 6. Specifically, the resin composition 6 of the semiconductor device a4 further includes a lead-side covering portion 63 and a lead-side covering portion 64. Fig. 25 is a plan view showing a semiconductor device a4, and corresponds to fig. 4 in the first embodiment. Fig. 26 is an enlarged partial view of a part of fig. 25. Fig. 27 is a sectional view taken along line XXVII-XXVII of fig. 25. Fig. 28 is a sectional view taken along line XXVIII-XXVIII of fig. 25.

In the semiconductor device a4, the second wire 32 and the third wire 33 are both bonding wires containing Al. The wire diameters of the second lead wire 32 and the third lead wire 33 are, for example, such thatLeft and right.

As shown in fig. 25, 26, and 27, the wire-side cover 63 covers the joint portion of the second lead 32 and the second wire 22. As shown in fig. 26 and 27, the lead-side cover 63 includes a lead-side first portion 631, a lead-side second portion 632, and a lead-side third portion 633. The lead-side first portion 631, the lead-side second portion 632, and the lead-side third portion 633 are integrally formed.

As shown in fig. 26 and 27, the wire-side first portion 631 is a portion interposed between the second bonding portion 322 of the second lead 32 and the sealing resin 5.

As shown in fig. 26 and 27, the wire-side second portion 632 is a portion interposed between the wire bonding portion 221 of the second wire 22 and the sealing resin 5. The wire-side second portion 632 is connected to the wire-side first portion 631.

As shown in fig. 26 and 27, the wire-side third portion 633 is a portion interposed between a part of the linear portion 323 of the second lead 32 and the sealing resin 5. Specifically, the wire-side third portion 633 is formed at a part of the linear portion 323 on the second bonding portion 322 side. The wire-side third portion 633 is connected to the wire-side first portion 631.

As shown in fig. 25, 26, and 28, the wire-side cover 64 covers a joint portion of the third lead 33 and the third wire 23. As shown in fig. 26 and 28, the lead-side covered portion 64 includes a lead-side first portion 641, a lead-side second portion 642, and a lead-side third portion 643. The lead-side first portion 641, the lead-side second portion 642, and the lead-side third portion 643 are integrally formed.

As shown in fig. 26 and 28, the wire-side first portion 641 is a portion interposed between the second bonding portion 332 of the third lead 33 and the sealing resin 5.

As shown in fig. 26 and 28, the wire-side second portion 642 is a portion interposed between the wire bonding portion 231 of the third wire 23 and the sealing resin 5. The wire-side second portion 642 is connected to the wire-side first portion 641.

As shown in fig. 26 and 28, the wire-side third portion 643 is a portion interposed between a part of the linear portion 333 of the third lead 33 and the sealing resin 5. Specifically, the wire-side third portion 643 is formed in a part of the linear portion 333 on the second bonding portion 332 side. The wire-side third portion 643 is connected to the wire-side first portion 641.

The semiconductor device a4 was provided with the resin composition 6 in the same manner as the semiconductor device a 1. The resin composition 6 covers the bonding portion (die pad side bonding portion or lead side bonding portion) of the lead frame 2 and the conductive member (e.g., the conductive bonding material 4 or the first lead 31). Therefore, in the semiconductor device a4, as in the semiconductor device a1, it is possible to suppress a failure due to peeling of the sealing resin 5.

According to the semiconductor device a4, the resin composition 6 includes the lead-wire-side covering portion 63, and the lead-wire-side covering portion 63 covers the joint portion of the second lead 32 and the second lead wire 22. With this configuration, the resin composition 6 functions as an adhesive, and the bonding strength between the bonding portion between the second lead 32 and the second lead 22 and the sealing resin 5 can be improved. Therefore, the semiconductor device a4 can suppress the peeling of the bonding portion from the sealing resin 5. If such peeling occurs, when a thermal load is applied to the semiconductor device a4, for example, a thermal stress acts on the neck portion of the second lead 32 (the portion where the second bonding portion 322 and the linear portion 323 are connected), and the neck portion may be broken. However, in the semiconductor device a4, the bonded portion between the second lead 32 and the second lead 22 and the sealing resin 5 can be prevented from peeling off, and the thermal stress acting on the neck portion can be relaxed. Therefore, the semiconductor device a4 can suppress a failure (for example, disconnection of the second lead 32) due to peeling of the sealing resin 5. In particular, in the semiconductor device a4, since the second lead 32 is a metal containing Al and the second wire 22 is a metal containing Cu, thermal stress acting on the neck portion is large. Therefore, relaxing the thermal stress acting on the neck portion by the lead-side cover 63 is effective for suppressing the failure of the semiconductor device a 4.

According to the semiconductor device a4, the second lead 32 is thinner than each of the first leads 31. Therefore, the second lead 32 is more likely to be broken due to corrosion than the first leads 31. However, since the resin composition 6 of the semiconductor device a4 includes the lead-side cover portion 63 and the lead-side cover portion 63 serves as a protective material, corrosion of the second lead 32 (e.g., the connection portion (neck portion) between the second bonding portion 322 and the linear portion 323) can be suppressed. That is, the semiconductor device a4 can suppress disconnection due to corrosion of the second lead 32.

According to the semiconductor device a4, the resin composition 6 includes the lead-wire-side covering portion 64, and the lead-wire-side covering portion 64 covers the joint portion of the third lead 33 and the third lead 23. With this configuration, the resin composition 6 functions as an adhesive, and the bonding strength between the bonding portion between the third lead 33 and the third lead 23 and the sealing resin 5 can be improved. Therefore, the semiconductor device a4 can suppress the peeling of the bonding portion from the sealing resin 5. If such peeling occurs, when a thermal load is applied to the semiconductor device a4, for example, a thermal stress acts on the neck portion of the third lead 33 (the connection portion between the second bonding portion 332 and the linear portion 333), and the neck portion may be broken. However, in the semiconductor device a4, since the bonded portion between the third lead 33 and the third lead 23 and the sealing resin 5 can be prevented from peeling, thermal stress acting on the neck portion can be relaxed. Therefore, the semiconductor device a4 can suppress a failure (e.g., disconnection of the third lead 33) caused by peeling of the sealing resin 5. In particular, in the semiconductor device a4, since the third lead 33 is a metal containing Al and the third wire 23 is a metal containing Cu, thermal stress acting on the neck portion is large. Therefore, relaxing the thermal stress acting on the neck portion by the lead-side cover portion 64 is effective for suppressing the failure of the semiconductor device a 4.

According to the semiconductor device a4, the third lead 33 is thinner than each of the first leads 31. Therefore, the third lead 33 is more likely to be broken due to corrosion than the first leads 31. However, since the resin composition 6 of the semiconductor device a4 includes the lead-side cover portion 64 and the lead-side cover portion 64 serves as a protective material, corrosion of the third lead 33 (e.g., the connection portion (neck portion) between the second bonding portion 332 and the linear portion 333) can be suppressed. That is, the semiconductor device a4 can suppress disconnection due to corrosion of the third lead 33.

In the fourth embodiment, the case where the second lead 32 and the third lead 33 are each composed of a metal containing Al is shown, but is not limited thereto. For example, the second lead 32 may be made of a metal containing Cu or a metal containing Au. At this time, the lead-wire-side covering portion 63 also serves as an adhesive, and the bonding strength between the sealing resin 5 and the bonding portion between the second lead 32 and the second lead 22 can be improved. Similarly, for example, the third lead 33 may be made of a metal containing Cu or a metal containing Au. At this time, the lead-wire-side covering portion 64 also serves as an adhesive, and the bonding strength between the sealing resin 5 and the bonding portion between the third lead 33 and the third lead 23 can be improved.

Fig. 29 to 31 show a semiconductor device according to a fifth embodiment. The semiconductor device a5 of the fifth embodiment is different from the semiconductor device a4 in the formation region of the resin composition 6. Specifically, the resin composition 6 of the semiconductor device a5 further includes an element-side cover portion 65. Fig. 29 is a plan view showing a semiconductor device a5, and corresponds to fig. 25 in the fourth embodiment. Fig. 30 is a cross-sectional view taken along line XXX-XXX of fig. 29. Fig. 31 is a cross-sectional view taken along line XXXI-XXXI of fig. 29.

The element-side cover 65 covers the bonding portion between the second lead 32 and the second main-surface electrode 112 and the bonding portion between the third lead 33 and the third main-surface electrode 113. The element-side cover 65 extends from these joining portions to the periphery, respectively, in a plan view. The element-side cover 65 overlaps a part of the first main-surface electrode 111 in a plan view, and covers a part of the first main-surface electrode 111. However, the element-side covering portion 65 (the resin composition 6) does not cover the portion of the first main surface electrode 111 to which each first lead 31 can be bonded (the region R1 shown in fig. 29). In the example of fig. 29, the element-side cover portion 65 is connected to the die-pad-side cover portion 61, but the element-side cover portion 65 may not be connected to the die-pad-side cover portion 61.

The semiconductor device a5 was provided with the resin composition 6 in the same manner as the semiconductor device a 1. The resin composition 6 covers the bonding portion (die pad side bonding portion or lead side bonding portion) of the lead frame 2 and the conductive member (e.g., the conductive bonding material 4 or the first lead 31). Therefore, in the semiconductor device a5, as in the semiconductor device a1, it is possible to suppress a failure due to peeling of the sealing resin 5.

According to the semiconductor device a5, the resin composition 6 includes the element-side cover part 65. The element-side cover 65 covers the bonding portion between the second lead 32 and the second main-surface electrode 112 and the bonding portion between the third lead 33 and the third main-surface electrode 113. By adopting this configuration, the resin composition 6 becomes an adhesive, and the bonding strength between the bonding portion of the second lead 32 and the second lead 22 and the sealing resin 5, and the bonding strength between the bonding portion of the third lead 33 and the third lead 23 and the sealing resin 5 can be improved. Therefore, the semiconductor device a5 can suppress peeling of the sealing resin 5 from these bonded portions, and can suppress a failure due to peeling of the sealing resin 5. Although a part of the element main surface 1a (mainly the second main surface electrode 112 and the third main surface electrode 113) is covered with the resin composition 6 by the element-side covering portion 65, the second main surface electrode 112 and the third main surface electrode 113 are less likely to generate heat than the first main surface electrode 111 when the semiconductor device a5 is operated. Therefore, the influence of the decrease in heat dissipation property due to the part of the element main surface 1a being covered with the resin composition 6 is small.

In the fifth embodiment, the case where the element-side cover portion 65 covers a part of the first main-surface electrode 111 is shown, but the present invention is not limited to this. For example, the element-side cover portion 65 may not cover the first main surface electrode 111. That is, the entire first main surface electrode 111 may be exposed from the resin composition 6.

In the fifth embodiment, the case where the resin composition 6 includes the die-pad-side covering portion 61, the plurality of lead-wire-side covering portions 62, 63, 64, and the element-side covering portion 65 is shown, but the resin composition 6 may not include all of these. That is, the resin composition 6 may contain at least one of these components.

Further, one or both of the lead-wire-side covering portion 63 shown in the fourth embodiment and the element-side covering portion 65 shown in the fifth embodiment may be added to the semiconductor device a 3.

In the first to fifth embodiments, the case where the semiconductor element 1 has a vertical structure including the main surface electrode 11 and the rear surface electrode 12 is shown, but the present invention is not limited thereto. For example, the semiconductor element 1 may have a horizontal structure (including the main surface electrode 11) without the back surface electrode 12. In this case, instead of the solder, Ag paste may be used as the conductive bonding material 4.

In the first to fifth embodiments, the die pad 24 of the lead frame 2 is shown in a case where the pad rear surface 24b is exposed from the sealing resin 5, but the present invention is not limited thereto, and the pad rear surface 24b may be covered with the sealing resin 5.

In the first to fifth embodiments, the semiconductor devices a1 to a5 are surface-mounted, but the semiconductor devices are not limited to the surface-mounted type and may be lead-inserted type. The semiconductor devices a1 to a5 are illustrated as the lead frame 2 protruding from the sealing resin 5 in a plan view, but the present invention is not limited to this. For example, the lead frame 2 may be of a so-called non-lead package type in which the lead frame does not protrude from the sealing resin 5 in a plan view. Therefore, the package shape of the semiconductor device of the present disclosure is not particularly limited, and can be applied to various package types.

The semiconductor device and the method for manufacturing the same of the present disclosure are not limited to the above-described embodiments. The specific structure of each part of the semiconductor device of the present disclosure and the specific processing of each step of the manufacturing method of the present disclosure can be variously modified in design.