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 高尾胜大 于 2017-08-04 设计创作，主要内容包括：本发明提供一种半导体装置,其具备在底面的一部分具有镀层部半导体元件以及密封所述半导体元件的所述底面以外的面的保护部件,所述镀层部与所述半导体元件内的电路电连接。(The invention provides a semiconductor device, which comprises a semiconductor element with a plating part at a part of the bottom surface and a protective component for sealing the surface of the semiconductor element except the bottom surface, wherein the plating part is electrically connected with the circuit in the semiconductor element.)

1. A semiconductor device includes a semiconductor element having a plated portion on a part of a main surface thereof and a protective member sealing a surface other than the main surface of the semiconductor element,

the plated portion is electrically connected to a circuit within the semiconductor element.

2. The semiconductor device according to claim 1, wherein an end portion of the main surface and a surface of the protective member are continuously formed.

3. The semiconductor device according to claim 1 or 2, wherein a thickness of the plated portion from the main surface is 15 μm or less.

4. The semiconductor device according to any one of claims 1 to 3, wherein the protective member is a uniform thermosetting resin.

5. The semiconductor device according to claim 4, wherein the protective member contains a predetermined filler.

6. A method for manufacturing a semiconductor device includes:

a plating part for electrical connection with a circuit in a semiconductor element is formed on a part of a main surface of the semiconductor element,

a surface other than the main surface of the semiconductor element is sealed by a protective member.

7. The method of manufacturing a semiconductor device according to claim 6, wherein an end portion of the main surface and a surface of the protective member are continuously formed.

8. The method for manufacturing a semiconductor device according to claim 7, wherein the plated portion is formed to have a thickness of 15 μm or less from the main surface.

9. The method for manufacturing a semiconductor device according to any one of claims 6 to 8, wherein a thermosetting resin is uniformly cured as the protective member.

10. The method for manufacturing a semiconductor device according to claim 9, wherein the thermosetting resin containing a predetermined filler is used as the protective member.

11. The method for manufacturing a semiconductor device according to any one of claims 6 to 10, wherein the protective member is formed by a vacuum lamination method.

Technical Field

The present invention relates to a semiconductor device and a method for manufacturing the semiconductor device.

Background

There is known a semiconductor device in which a terminal for external connection is directly mounted on a die without internal wiring using a bonding wire. For example, patent document 1 describes a semiconductor device having a structure in which bumps for external connection are provided on one surface of a bare chip, and the other surface is sealed with a protective resin.

Disclosure of Invention

Problems to be solved by the invention

In the conventional semiconductor device described in patent document 1, since the mounting terminal is formed of a solder bump, it is difficult to control the thickness of the semiconductor device in the height direction.

Means for solving the problems

According to a first aspect of the present invention, a semiconductor device includes a semiconductor element having a plated portion on a part of a main surface thereof, and a protective member sealing a surface other than the main surface of the semiconductor element, wherein the plated portion is electrically connected to a circuit in the semiconductor element.

According to a second aspect of the present invention, a method for manufacturing a semiconductor device includes: a plating section for electrical connection to a circuit in a semiconductor element is formed in a part of a main surface of the semiconductor element, and a surface other than the main surface of the semiconductor element is sealed with a protective member.

Effects of the invention

According to the present invention, the thickness of the semiconductor device in the height direction can be easily controlled.

Drawings

Fig. 1 is a schematic diagram of a semiconductor device according to a first embodiment, where (a) is a cross-sectional view of the semiconductor device, and (b) is a plan view of the semiconductor device as viewed from a principal surface side.

In fig. 2, (a) to (d) are sectional views for explaining a method of manufacturing a semiconductor device.

In fig. 3, (a) to (d) are sectional views for explaining the method of manufacturing the semiconductor device after fig. 2.

In fig. 4, (a) to (d) are sectional views for explaining the method of manufacturing the semiconductor device after fig. 3.

In fig. 5, (a) to (d) are sectional views for explaining the method of manufacturing the semiconductor device after fig. 4.

In fig. 6, (a) and (b) are sectional views of a semiconductor device according to a modification example.

Detailed Description

Hereinafter, the semiconductor device, the method for manufacturing the semiconductor device, and the like according to the first embodiment will be described with reference to the drawings as appropriate. In the following embodiments, a surface of the semiconductor device provided with the external connection terminals is defined as a main surface of the semiconductor device, a vertical direction is defined as a direction perpendicular to the main surface, and a direction from the main surface of the semiconductor device toward the outside is defined as an upward direction (upward direction). In the following embodiments, the term "connected" includes the meaning that 2 substances to be connected can conduct electricity.

(first embodiment)

Fig. 1 is a schematic view of a semiconductor device according to a first embodiment of the present invention. Fig. 1(a) is a sectional view of the semiconductor device 1, and fig. 1(b) is a plan view of the semiconductor device 1 as viewed from the principal surface side.

The semiconductor device 1 includes a semiconductor element 10, a pad 11a, a pad 11b, a mounting terminal 12a, a mounting terminal 12b, and a sealing resin 13. The terminal forming surface S of the semiconductor element 10 on which the pad 11a and the pad 11b are formed is a main surface. The pad 11a and the pad 11b are arranged side by side on the terminal forming surface S. Mounting terminals 12a are provided above the pads 11a in the direction. The pad 11a is electrically connected to the mounting terminal 12 a. Mounting terminals 12b are provided above the pads 11b in the direction of the upper surface. The pad 11b is electrically connected to the mounting terminal 12 b.

In the following description, the pads 11a and 11b are collectively referred to as the pads 11. Similarly, the mounting terminals 12a and 12b are collectively referred to as mounting terminals 12.

An insulating protective layer 16 is formed on the terminal forming surface S at a portion where the pad 11 is not formed. The insulating protective layer 16 insulates the semiconductor element 10 and protects the semiconductor element 10 from foreign substances and the like. The insulating protective layer 16 includes a passivation film 17 formed on the terminal forming surface S and a protective film 18 formed on the passivation film 17.

The mounting terminal 12 includes a first conductive layer 14 formed on the pad 11 and a second conductive layer 15 formed on the first conductive layer 14. The first conductive layer 14 is made of a conductor such as copper, for example. The second conductive layer 15 is made of a conductor such as tin or silver.

The semiconductor element 10 is a bare semiconductor chip obtained by dicing a wafer as a semiconductor substrate. The semiconductor element 10 includes a single circuit such as a diode, or includes an electronic circuit such as an integrated circuit or a large-scale integrated circuit. The pad 11a and the pad 11b are made of metal such as aluminum, for example. The sealing resin 13 is a protective member for sealing 5 of the 6 surfaces of the semiconductor device 1 except for the terminal forming surface S on which the mounting terminal 12 and the insulating protective layer 16 are provided.

(method for manufacturing semiconductor device 1)

A method for manufacturing the semiconductor device 1 will be described below with reference to fig. 2 to 5. The semiconductor device 1 can be manufactured by sequentially performing steps 1 to 14 on a wafer 20 of material.

Fig. 2 and 3 show only the regions corresponding to 1 semiconductor device 1 among the plurality of semiconductor devices 1 formed on the wafer 20. In practice, a plurality of semiconductor device formation regions for forming the semiconductor device 1 illustrated in fig. 2 and 3 are formed on the wafer 20.

As shown in fig. 2(a), a pad 11a and a pad 11b are formed on the wafer 20 by a method such as vapor deposition. On the terminal formation surface S of the wafer 20 on which the pad 11 is formed, a passivation film 17 is formed from the upper surface of the pad 11.

In the passivation film 17, an opening 21 is formed in an upper region of the pad 11. The pad 11 is exposed from the opening 21 of the passivation film 17.

(step 1)

In step 1, a wafer 20 is coated with polyimide. A polyimide resin is applied to the wafer 20 shown in fig. 2(a), and exposure, development, and curing are performed using a photomask having a predetermined pattern formed thereon. Thereby, the wafer 20 is in the state shown in fig. 2 (b). In fig. 2(b), a protective film 18 made of a polyimide resin is formed on the passivation film 17. The thickness of the protective film 18 is, for example, about 5 μm. The protective film 18 is not formed on the opening 21.

(step 2)

In step 2, a seed layer 22 for plating is formed. A seed layer 22 is formed on the pad 11 and the protective film 18 shown in fig. 2(b) by sputtering or the like. The seed layer 22 is a thin film functioning as an Under Bump Metallurgy (UBM). The seed layer 22 is formed by, for example, forming titanium (Ti) as an adhesion layer and forming copper (Cu) thereon. Thereby, the wafer 20 is in the state shown in fig. 2 (c). In fig. 2(c), a seed layer 22 is formed on the protective film 18 and the opening 21.

(step 3)

In step 3, the plating resist 23 is formed. The seed layer 22 shown in fig. 2(c) is coated with a plating resist, and exposed to light using a photomask having a predetermined pattern formed thereon, followed by development. Thereby, the wafer 20 is in the state shown in fig. 2 (d). In fig. 2(d), a plating resist 23 is formed on the seed layer 22. The plating resist 23 is not formed on the opening 21, which is the portion where the mounting terminal 12 is formed.

(step 4)

In step 4, first conductive layer 14 of mounting terminal 12 is formed. The first conductive layer 14 is formed by electroplating on a portion where the plating resist 23 shown in fig. 2(d) is not formed. The first conductive layer 14 is made of copper, for example. Thereby, the wafer 20 is in the state shown in fig. 3 (a). In fig. 3(a), the first conductive layer 14, which is a part of the mounting terminal 12, is formed on the opening 21.

(step 5)

In step 5, second conductive layer 15 for mounting terminal 12 is formed. On the first conductive layer 14 illustrated in fig. 3(a), a second conductive layer 15 is formed by electroplating. The second conductive layer 15 is formed of a metal containing tin and silver, for example. Thereby, the wafer 20 is in the state shown in fig. 3 (b). In fig. 3(b), mounting terminals 12 including first conductive layer 14 and second conductive layer 15 are formed on opening 21.

In order to reduce the mounting thickness of the semiconductor device 1, the thickness of the mounting terminal 12 from the surface of the insulating protective layer 16 is preferably 15 μm or less. For example, if the thickness of the first conductive layer 14 is about 8 μm and the thickness of the second conductive layer 15 is about 3 μm, such a thickness can be achieved.

(step 6)

In step 6, the plating resist 23 is removed. Since the first conductive layer 14 and the second conductive layer 15 shown in fig. 3(b) are already formed, the plating resist 23 is not needed and is removed. Thereby, the wafer 20 is in the state shown in fig. 3 (c). In fig. 3(c), the plating resist 23 formed in the portions other than the mounting terminals 12a and 12b is removed.

(step 7)

In step 7, the exposed seed layer 22 is removed. The exposed seed layer 22 is removed by etching to insulate the mounting terminals 12 illustrated in fig. 3(c) from each other. Thereby, the wafer 20 is in the state shown in fig. 3 (d). In fig. 3(d), the exposed seed layer 22 existing between the mounting terminals 12a and 12b is removed.

Fig. 4(a) shows a part of the た wafer 20 having undergone the above steps 1 to 7. Fig. 4 and 5 schematically illustrate regions of the wafer 20 corresponding to 3 semiconductor devices 1.

(step 8)

In step 8, the back grinding and the sticking to the dicing tape are performed. By the back grinding, the wafer 20 is removed from the bottom surface side opposite to the main surface, and thinned to a predetermined thickness. Then, the bottom surface of the wafer 20 is attached to the dicing tape 30. Thereby, the wafer 20 is in the state shown in fig. 4 (b). In fig. 4(b), a dicing tape 30 is attached to the surface of the wafer 20, i.e., the bottom surface of the surface opposite to the main surface on which the mounting terminals 12 are formed.

(step 9)

In step 9, the semiconductor device 1 is diced. That is, the wafer 20 is cut from the upper side together with the protective film 18 and the passivation film 17 at the boundary of the region (semiconductor device formation region) for forming the semiconductor device 1. The cutting is performed to the middle of the thickness of the dicing tape 30. By cutting the wafer 20, a plurality of regions where the semiconductor devices 1 are to be formed, which are to be extracted from the wafer 20, are separated from each other. Thereby, the wafer 20 is in the state shown in fig. 4 (c). In fig. 4(c), the respective wafers separated from each other are bonded to the dicing tape 30.

(Process 10)

In step 10, the tape is replaced. After the support tape 31 is attached so as to cover the terminal forming surface S of the wafer 20, the dicing tape 30 attached to the bottom surface of the wafer 20 is peeled off. Thereby, the wafer 20 is in the state shown in fig. 4 (d). In fig. 4(d), the mounting terminal 12 is embedded in the support tape 31. The surface of the support tape 31 is in contact with the surface 16a of the insulating protective layer 16.

(step 11)

In step 11, resin sealing is performed. For example, by vacuum lamination, and sealing 5 surfaces other than the terminal forming surface S to which the support tape 31 is attached with the sealing resin 13. For example, the wafer 20 is covered with a film-like thermosetting resin, and heated at 120 to 150 degrees celsius under a vacuum of 1hpa or less while applying a pressure of 0.5 MPa. Thereby, as shown in fig. 5(a), in the wafer 20, the sealing resin 13 is filled between the separated semiconductor device forming regions (chips), and one surface 13a of the sealing resin 13 becomes flat. That is, in fig. 5(a), the wafers separated once in step 9 are bonded to each other again with the sealing resin 13. Further, since the resin sealing is performed in a state where the surface of the support tape 31 is in contact with the surface 16a of the insulating protective layer 16, the surface 13b of the sealing resin 13 in contact with the support tape 31 and the surface 16a of the insulating protective layer 16 are flush with each other.

In order to make the thickness of the semiconductor device 1 thinner, the thickness h of the sealing resin 13 on the surface (upper surface) of the wafer 20 is preferably 30 μm or less. In order to more reliably seal the wafers with the sealing resin 13, it is desirable that the sealing resin 13 contain a filler (filler). The resin in which the micron-sized and nano-sized fillers are dispersed can improve strength, heat resistance, flame retardancy, and insulation properties, and can be easily thinned and planarized.

Here, a pressing for flattening the one surface 13a of the sealing resin 13 may be further added. When the thickness of the upper surface of the sealing resin 13 is equal to or more than a certain value, unevenness may be generated on the upper surface of the sealing resin 13, but by increasing the pressing, the upper surface of the sealing resin 13 can be made uniform.

(step 12)

In step 12, the respective wafers integrated with the sealing resin 13 are peeled off from the support tape 31. When the support tape 31 has a property that the adhesive force is reduced by heating, it is desirable to peel the support tape 31 while heating. After the support tape 31 is peeled off, post-curing is performed as necessary to fix the sealing resin 13. If post-curing is performed after peeling the support tape 31, the thermal characteristics of the support tape 31 need not be considered. When the support tape 31 has high heat resistance, post-curing may also be performed before peeling the support tape 31. Thereby, the wafer 20 is in the state shown in fig. 5 (b). In fig. 5(b), as described above, the surface 13b of the sealing resin 13 in contact with the support tape 31 and the surface 16a of the insulating protective layer 16 are continuously formed and are in the same plane.

(step 13)

In step 13, a dicing tape 32 is attached to the surface of the wafer 20. Thereby, the wafer 20 is in the state shown in fig. 5 (c).

(step 14)

In step 14, dicing is performed. The sealing resin 13 filled between the wafers is cut so as to leave a desired thickness from the peripheral side edge of each wafer. Thereby, the wafer 20 is in the state shown in fig. 5 (d). In fig. 5(d), a plurality of semiconductor devices 1 are attached to the dicing tape 32.

According to the above embodiment, the following operational effects can be obtained.

(1) The semiconductor element 10 has a mounting terminal 12 formed of a plating layer on a part of the terminal forming surface S. The surface of the semiconductor element 10 other than the terminal forming surface S is sealed with a sealing resin 13. The mounting terminals 12 are electrically connected to a circuit in the semiconductor element 10. Due to this design, the thickness of the semiconductor device 1 in the height direction can be easily controlled. In particular, the mounting thickness of the semiconductor device 1 can be made thinner than in the past.

(2) The end portion of the bottom surface S of the semiconductor element 10 (the end portion of the insulating protective layer 16) and the surface of the sealing resin 13 are formed continuously, i.e., so as to form the same plane. With this design, the semiconductor element 10 can be reliably sealed, and high insulation can be ensured. Further, since the side surface of the mounting terminal 12 is completely exposed without embedding the sealing resin 13, the mounting terminal 12 can be formed extremely thin.

In the case where the mounting terminal 12 is formed by a thin plating layer instead of a solder ball having a height, the distance from the surface of the mounting terminal 12 to the side surface of the semiconductor element 10 is short, and the possibility that the solder will climb along the side surface of the semiconductor element 10 when the mounting terminal 12 is soldered is high.

As described in the above embodiment, by sealing the side surfaces of the semiconductor element 10 with the sealing resin 13, short-circuiting at the time of mounting due to solder rising can be suppressed. Further, according to the manufacturing method of the above embodiment, the side surface and the back surface of the semiconductor element 10 can be reliably sealed with a uniform thickness. Further, according to this manufacturing method, the thickness of the sealing resin 13 on the side surface can be easily controlled by changing the cutting width.

(3) The thickness of the mounting terminal 12 from the bottom surface S is 15 μm or less. Due to such a design, the mounting thickness of the semiconductor device 1 can be significantly reduced as compared with a conventional semiconductor device having a thickness of, for example, about 50 μm.

(4) The sealing resin 13 is cured in a single step 11 and is uniformly formed. Due to such a design, resin sealing can be performed more firmly and more quickly than in the conventional technique such as cited document 1 in which the resin is formed by potting in a different process.

(5) The sealing resin 13 is formed by a vacuum lamination method. With this design, the thickness of the sealing resin on the upper surface of the semiconductor device 1 can be more reliably controlled.

The following modifications are also within the scope of the present invention, and one or more of the modifications may be combined with the above-described embodiment.

(modification 1)

The method of forming the mounting terminal 12 is not limited to the method of steps 1 to 7. For example, the mounting terminal 12 may be formed by the method described below instead of the steps 1 to 7.

The semiconductor device 1a shown in fig. 6(a) is formed with the mounting terminals 12 by a method different from the method of steps 1 to 7. First, as a pretreatment for plating, the solder pad 11 is subjected to zincate treatment. Then, a first conductive layer 31 made of nickel (Ni) is formed on the pad 11 by electroless plating. On this, a second conductive layer 32 made of palladium (Pd) and a third conductive layer 33 made of gold (Au) are formed in this order by electroless plating.

In order to reduce the mounting thickness of the semiconductor device 1, the thickness of the mounting terminal 12 when viewed from the surface of the insulating protective layer 16 is desirably 15 micrometers or less, and more preferably 10 micrometers or less. For example, if the thickness of the first conductive layer 31 is about 8 μm and the thicknesses of the second conductive layer 32 and the third conductive layer 33 are about 0.05 μm, such thicknesses can be realized.

If the mounting terminal 12 is formed as described above, the process can be shortened as compared with the case of using the method of steps 1 to 7, and the thickness of the mounting terminal can be easily controlled.

The semiconductor device 1b shown in fig. 6(b) has mounting terminals 12 formed by a method different from the method of steps 1 to 7. First, as a pretreatment, a sputtering treatment using high-frequency power is performed to remove an oxide film and the like on the surface of the pad 11. Next, similarly to step 2, a seed layer 22 made of titanium (Ti), copper (Cu), or the like is formed by a sputtering method or the like. Over this, a first conductive layer 41 made of nickel (Ni) is formed by electroplating. On the first conductive layer 41, a second conductive layer 42 made of nickel (Ni), a third conductive layer 43 made of palladium (Pd), and a fourth conductive layer 44 made of gold (Au) are formed in this order by electroless plating. Then, the exposed seed layer 22 is removed by etching in the same manner as in step 7.

In order to reduce the mounting thickness of the semiconductor device 1, the thickness of the mounting terminal 12 when viewed from the surface of the insulating protective layer 16 is desirably 15 micrometers or less, and more preferably 10 micrometers or less. For example, if the thickness of first conductive layer 41 is about 7 micrometers, the thickness of second conductive layer 42 is about 1 micrometer, and the thicknesses of third conductive layer 43 and fourth conductive layer 44 are about 0.05 micrometer, such thicknesses can be realized.

If the mount terminal 12 is formed as described above, the thickness of the mount terminal can be easily controlled even in a case where the pad 11 cannot be directly electroless-plated.

Note that the third conductive layer 43 may be omitted.

In the above, various embodiments and modifications have been described, but the present invention is not limited to these. Other modes that can be conceived within the scope of the technical idea of the present invention are also included in the scope of the present invention.

The disclosures of the following priority base applications are hereby incorporated by reference.

Japanese patent application No. 106608 in 2017 (application on 5/30/2017)

Description of the symbols

1. 1a, 1b … semiconductor device, 10 … semiconductor element, 11a, 11b … pad, 12a, 12b … mounting terminal, 13 … sealing resin, 14, 31, 41 … first conductive layer, 15, 32, 42 … second conductive layer, 16 … insulating protective layer, 17 … passivation film, 18 … protective film, 22 … seed layer, 33, 43 … third conductive layer, 44 … fourth conductive layer.

The claims (modification according to treaty clause 19)

A semiconductor device (after correction) comprising:

a semiconductor element having a pad electrically connected to the internal circuit and a plated portion on a part of a main surface,

an insulating protective layer covering the main surface and having an opening portion exposing the pad, and

a protective member sealing a surface other than the main surface of the semiconductor element;

the insulating protective layer has a passivation film and a protective film formed of a resin on the passivation film, the opening is formed inside a peripheral edge portion of the pad,

the protective member is formed continuously with the protective film so as to cover at least a part of a side surface of the protective film at an end portion of the main surface,

the plated portion is a mounting terminal connected to the pad through an opening of the protective film, and the mounting terminal is formed by laminating a plurality of plated layers and protrudes from an upper surface of the protective film.

The semiconductor device according to claim 1, wherein a surface of the protective member and a surface of the protective film are formed on the same plane at an end of the main surface (after correction).

The semiconductor device according to claim 1 or 2, wherein a thickness of the plated portion from a surface of the insulating protective layer is 15 μm or less.

The semiconductor device according to any one of claims 1 to 3, wherein the protective member is a uniform thermosetting resin having a thickness of 30 μm or less on the side opposite to the main surface (after correction).

5. The semiconductor device according to claim 4, wherein the protective member contains a predetermined filler.

A method for manufacturing a semiconductor device (after correction), comprising:

forming a plated portion connected to a pad on a part of a main surface of a semiconductor element having the pad electrically connected to an internal circuit,

sealing a surface other than the main surface of the semiconductor element with a protective member;

the formation of the plated portion includes forming an insulating protective layer covering the main surface and having an opening portion exposing the pad,

the forming of the insulating protective layer includes forming a passivation film and a protective film formed of a resin on the passivation film such that an opening of the passivation film and an opening of the protective film are disposed inside a peripheral edge of the pad,

the manufacturing method includes forming the protective member so as to cover at least a part of a side surface of the protective film and to be continuous with the protective film at an end portion of the main surface,

the manufacturing method includes forming the plated portion as a mounting terminal connected to the pad via the opening of the protective film, and forming the mounting terminal by laminating a plurality of plated layers so as to protrude from an upper surface of the protective film.

The method for manufacturing a semiconductor device according to claim 6, wherein a surface of the protective member and a surface of the protective film are formed on the same plane at an end of the main surface (after correction).

The method for manufacturing a semiconductor device according to claim 7, wherein the plated portion is formed to have a thickness of 15 μm or less from a surface of the insulating protective layer.

The method for manufacturing a semiconductor device according to any one of claims 6 to 8, wherein the protective member is formed by uniformly curing a thermosetting resin, and has a thickness of 30 μm or less on the surface side opposite to the main surface.

10. The method for manufacturing a semiconductor device according to claim 9, wherein the thermosetting resin containing a predetermined filler is used as the protective member.

The method for manufacturing a semiconductor device according to any one of claims 6 to 10 (after correction), wherein the protective member is formed by covering a surface other than the main surface of the semiconductor element with a film-like thermosetting resin by a vacuum lamination method and heating the film-like thermosetting resin.