阅读说明：本技术 一种半导体器件封装结构 (Semiconductor device packaging structure ) 是由 朱袁正 王燕军 李明芬 朱久桃 于 2019-12-06 设计创作，主要内容包括：本发明涉及半导体器件封装技术领域,具体公开了一种半导体器件封装结构,其中,包括：半导体芯片、金属键合线、封装体、金属基岛和引脚,所述半导体芯片焊接在所述金属基岛的上表面,所述半导体芯片和所述引脚之间通过金属键合线连接,所述封装体封盖在所述半导体芯片、金属键合线、金属基岛和引脚上,并露出部分所述引脚和部分所述金属基岛,位于所述封装体外的所述金属基岛的顶端设置连筋,被所述封装体封盖的所述金属基岛的底端悬空。本发明提供的半导体器件封装结构提升了半导体器件的功率,即提升了半导体器件的性能,同时由于省去了连筋,也节省了成本。(The invention relates to the technical field of semiconductor device packaging, and particularly discloses a semiconductor device packaging structure, which comprises: the semiconductor chip is welded on the upper surface of the metal base island, the semiconductor chip is connected with the pins through the metal bonding wires, the packaging body covers the semiconductor chip, the metal bonding wires, the metal base island and the pins, a part of the pins and a part of the metal base island are exposed, and a connecting rib is arranged at the top end of the metal base island outside the packaging body and is suspended at the bottom end of the metal base island of the packaging body cover. The semiconductor device packaging structure provided by the invention improves the power of the semiconductor device, namely the performance of the semiconductor device, and simultaneously saves the cost due to the fact that connecting ribs are omitted.)

1. A semiconductor device package structure, comprising: the semiconductor chip is welded on the upper surface of the metal base island, the semiconductor chip is connected with the pins through the metal bonding wires, the packaging body covers the semiconductor chip, the metal bonding wires, the metal base island and the pins, a part of the pins and a part of the metal base island are exposed, and a connecting rib is arranged at the top end of the metal base island outside the packaging body and is suspended at the bottom end of the metal base island of the packaging body cover.

2. The semiconductor device package structure according to claim 1, wherein one end of the lead is connected to the semiconductor chip through the metal bonding wire, the other end of the lead extends out of the package body after being bent, and a bottom surface of the bent lead is coplanar with a lower surface of the metal base island.

3. The semiconductor device package structure of claim 1, wherein the portion of the leads capped by the package body forms a bonding platform, an upper surface of the bonding platform being coplanar with an upper surface of the semiconductor chip.

4. The semiconductor device package structure of claim 3, wherein the leads comprise a first lead and a second lead, the first lead and the second lead are spaced apart, a portion of the second lead located in the package body forms a bonding platform, and one end of the bonding platform extends in a direction of the first lead and is disposed adjacent to the first lead.

5. The semiconductor device package structure of claim 1, wherein ear structures are disposed on two sides of the metal base island, and the ear structures are exposed outside the package body.

6. The semiconductor device package structure of claim 1, wherein the metal base island is provided with symmetrical through holes, and the through holes are filled with the package body.

7. The semiconductor device package structure according to any one of claims 1 to 6, wherein the semiconductor chip comprises any one of an IC, a MOSFET, a SIC, a Schottky, and an IGBT.

8. The semiconductor device package structure according to any one of claims 1 to 6, wherein the metal base island has a thickness in a range of 0.30mm to 0.51 mm.

9. The semiconductor device package structure of any one of claims 1 to 6, wherein the metal bonding wire comprises any one of an aluminum wire, a copper wire, an aluminum tape, and a copper sheet.

10. The semiconductor device package structure according to any one of claims 1 to 6, wherein the leads have a width in a range of 0.7mm to 0.9mm, a length in a range of 1.4mm to 1.8mm, and a thickness in a range of 0.30mm to 0.51 mm.

Technical Field

The invention relates to the technical field of semiconductor device packaging, in particular to a semiconductor device packaging structure.

Background

The TO252 package, which is a mainstream chip package (with specific structure shown in fig. 12 TO 14), has a large market demand, but the internal structure and the external shape of the TO252 package product manufactured by each large packaging enterprise in the industry are almost the same. If the packaging product is manufactured and processed according to the current same packaging design structure, no breakthrough advantage exists in the aspects of device performance and manufacturing cost, and the current requirements on different types of packaging forms cannot be met.

Disclosure of Invention

The invention provides a semiconductor device packaging structure, which solves the problems of low performance and high cost of the packaging structure in the prior art in the related art.

As an aspect of the present invention, there is provided a semiconductor device package structure, including: the semiconductor chip is welded on the upper surface of the metal base island, the semiconductor chip is connected with the pins through the metal bonding wires, the packaging body covers the semiconductor chip, the metal bonding wires, the metal base island and the pins, a part of the pins and a part of the metal base island are exposed, and a connecting rib is arranged at the top end of the metal base island outside the packaging body and is suspended at the bottom end of the metal base island of the packaging body cover.

Furthermore, one end of the pin is connected with the semiconductor chip through the metal bonding wire, the other end of the pin extends out of the packaging body after being bent, and the bottom surface of the bent pin is coplanar with the lower surface of the metal base island.

Further, the portion of the leads that are capped by the package form a bonding platform, an upper surface of the bonding platform being coplanar with an upper surface of the semiconductor chip.

Furthermore, the leads include a first lead and a second lead, the first lead and the second lead are arranged at an interval, a portion of the second lead located in the package body forms a bonding platform, and one end of the bonding platform extends towards the direction of the first lead and is arranged adjacent to the first lead.

Furthermore, ear structures are arranged on two sides of the metal base island, and the ear structures are exposed outside the packaging body.

Furthermore, symmetrical through holes are formed in the metal base island, and the packaging body is filled in the through holes.

Further, the semiconductor chip includes any one of an IC, a MOSFET, a SIC, a Schottky, and an IGBT.

Furthermore, the thickness range of the metal base island is 0.30 mm-0.51 mm.

Further, the metal bonding wire includes any one of an aluminum wire, a copper wire, an aluminum tape, and a copper sheet.

Furthermore, the width range of the pin is 0.7 mm-0.9 mm, the length range is 1.4 mm-1.8 mm, and the thickness range is 0.30 mm-0.51 mm.

Through above-mentioned semiconductor device packaging structure, metal base island top is provided with even muscle, the bottom is unsettled, there is not the even muscle of downwardly extending, save unnecessary even muscle like this, the device inner space has been practiced thrift, make pin bonding platform area can expand, thereby can allow the bonding of the metal bonding wire of large cross-sectional area to do on this platform, promote the voltage of device structure by a wide margin, the electric current conducting capacity, and then promote semiconductor device's power, semiconductor device's performance has been promoted promptly, simultaneously owing to saved even muscle, the cost has also been saved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

fig. 1 is a front view of a semiconductor device package structure provided by the present invention.

Fig. 2 is a rear view of a semiconductor device package structure provided by the present invention.

Fig. 3 is a schematic cross-sectional view of a semiconductor device package structure provided in the present invention.

Fig. 4 is a front view of a semiconductor device package structure according to the present invention.

Fig. 5 is a schematic rear view of a semiconductor device package structure according to the present invention.

Fig. 6 is a schematic right-view external view of the semiconductor device package structure provided in the present invention.

Fig. 7 is a schematic diagram of an aluminum tape bonding embodiment of the semiconductor device package structure provided in the present invention.

Fig. 8 is a schematic diagram of a copper sheet bonding embodiment of the semiconductor device package structure provided by the invention.

Fig. 9 is a schematic diagram of a multi-pin embodiment of a semiconductor device package structure according to the present invention.

Fig. 10 is a front view of a lead head recess and a package body bottom recess of a semiconductor device package structure provided by the present invention.

Fig. 11 is a side view of a lead header recess and a package body bottom recess of a semiconductor device package structure provided in the present invention.

Fig. 12 is an external front view of a TO252 package in the related art.

Fig. 13 is an external rear view of a prior art TO252 package.

Fig. 14 is an external side view of a prior art TO252 package.

Fig. 15 is a diagram showing simulation results of a TO252 package in the prior art.

Fig. 16 is a schematic diagram of a simulation result of the semiconductor device package structure according to the present invention.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged under appropriate circumstances in order to facilitate the description of the embodiments of the invention herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

In this embodiment, a semiconductor device package structure is provided, and fig. 1 to 3 are schematic structural diagrams of a semiconductor device package structure according to an embodiment of the present invention, as shown in fig. 1 to 3, where the structure includes: the semiconductor chip 1 is welded on the upper surface of the metal base island 2, the semiconductor chip 1 is connected with the pins 4 through the metal bonding wires 3, the packaging body 5 covers the semiconductor chip 1, the metal bonding wires 3, the metal base island 2 and the pins 4 and exposes part of the pins 4 and part of the metal base island 2, and connecting ribs are arranged at the top end of the metal base island 2 outside the packaging body 5 and are suspended at the bottom end of the metal base island 2 covered by the packaging body.

Through above-mentioned semiconductor device packaging structure, metal base island top is provided with even muscle, the bottom is unsettled, there is not the even muscle of downwardly extending, save unnecessary even muscle like this, the device inner space has been practiced thrift, make pin bonding platform area can expand, thereby can allow the bonding of the metal bonding wire of large cross-sectional area to do on this platform, promote the voltage of device structure by a wide margin, the electric current conducting capacity, and then promote semiconductor device's power, semiconductor device's performance has been promoted promptly, simultaneously owing to saved even muscle, the cost has also been saved.

Specifically, the back surface of a semiconductor chip 1 is welded on the upper surface of a metal base island 2, the front surface of the semiconductor chip 1 is connected with pins 4 through metal bonding wires 3, part of the pins 4 and part of the metal base island 2 are exposed after the encapsulation of a packaging body 5, the exposed metal base island 2 is used as a radiating fin on the bottom surface of a device, and the radiating fin is directly welded and attached to a PCB during application, so that on one hand, large current can be output, on the other hand, heat can be directly radiated through the PCB, and good performance of the device is ensured.

Specifically, one end of the pin 4 is connected to the semiconductor chip 1 through the metal bonding wire 3, the other end of the pin 4 extends out of the package 5 after being bent, and the bottom surface of the bent pin 4 is coplanar with the lower surface of the metal base island 2.

It can be understood that, the above-mentioned pin 4, the part that exposes the packaging body 5, the bottom surface that is on a parallel with the packaging body directly stretches out, does not have the bending, and the bottom surface of pin 4 and the lower surface of metal base island 2 are coplane, and the beneficial effect of this kind of plain leg structure is, compare traditional gull foot structure (for example TO252 packaging structure), and pin length shortens, has reduced the copper product use amount when promoting electric conduction, thermal conductivity again, has reduced production manufacturing cost. In addition, the pin stretches out perpendicularly and stretches out than the middle part, and the pin need not to bend, and the actual length of pin shortens, has reduced the use amount of copper product.

Specifically, the portion of the leads 4 covered by the package 5 forms a bonding stage 10, and the upper surface of the bonding stage 10 is coplanar with the upper surface of the semiconductor chip 1.

It should be noted that, the portion of the lead 4 covered by the package body is bent upward to form the bonding platform 10, and the upper surface of the bonding platform 10 is approximately flush with the upper surface of the semiconductor chip 1, so that the longitudinal space of the device can be saved, the device can be designed to be thinner, and meanwhile, the usage amount of the molding compound is reduced, and the manufacturing cost is reduced.

Specifically, as shown in fig. 1 and 4, the lead 4 includes a first lead 41 and a second lead 42, the first lead 41 and the second lead 42 are disposed at an interval, a portion of the second lead 42 located in the package body 5 forms a bonding platform 10, and one end of the bonding platform 10 extends toward the first lead 41 and is disposed adjacent to the first lead 41.

It can be understood that, taking the direction shown in fig. 4 as an example, the first lead 41 is a left lead, the second lead 42 is a right lead, the bonding platform 10 formed by bending the right lead upwards extends leftwards to an infinite right boundary close to the left lead, and the area of the bonding platform is large enough to allow a metal bonding wire with a large cross-sectional area to bond on the platform, so that the voltage and current conduction capability of the device structure is greatly improved.

Specifically, as shown in fig. 5, the bottom surface of the pin 4 is provided with a small groove 9 near the head region of the pin 4, so that the bottom surface of the pin is more easily tin-plated when the application terminal is soldered to the upper board.

Preferably, the substrate of the pin 4 can be designed in various forms, for example, TO be equivalent TO a TO263 package or DFN5x6 package pin substrate.

It should be understood that the number of the pins is preferably two, but not limited to two, and a plurality of pins may be provided as required, and the embodiment of the present invention is described by taking two pins as an example.

Specifically, two sides of the metal base island 2 are provided with ear structures, and the ear structures are exposed outside the packaging body 5.

It can be understood that the left side and the right side of the metal base island 2 are provided with the ear structures with the protruding sidelines, after plastic packaging, the upper surface of each ear structure is partially exposed, no packaging body sealing cover is arranged, and by arranging the ear structures, the metal thimble of the plastic packaging mold is contacted with and presses the ears, so that the metal base island 2 is ensured to be horizontal, and plastic packaging materials are prevented from overflowing to the lower surface heat dissipation sheet of the metal base island 2.

Specifically, as shown in fig. 1, symmetrical through holes 7 are provided on the metal base island 2, and the package is filled in the through holes 7.

It can be understood that two through-holes 7 of bilateral symmetry are provided near the upper end on 2 upper surfaces of metal base island, and the through-hole is filled up by the plastic envelope material behind the plastic envelope, and packaging body 5 runs through the lead frame through the through-hole, and is fixed with packaging body 5, prevents that the device from dropping and causes the fracture, and the design of symmetry for the mode locking effect is better.

As shown in fig. 1, V-shaped grooves 6 are provided on the upper surface of the metal base island 2 below the through-holes 7.

Specifically, as shown in fig. 6, the thickness of the package body 5 is less than 1.5mm, and compared with the prior art, the thickness of the device is thinner, so that a heat conduction path from the inside of the device to the surface of the plastic package body can be shortened, and heat can be more easily dissipated.

More specifically, as shown in fig. 10 and 11, a transverse groove 8 is formed in a region of the back surface of the package body located between the surface of the pin 2 and the surface of the metal base island 2, and the application end may brush red glue in the groove to prevent the device from falling off in subsequent wave soldering or reflow soldering processes.

Preferably, the semiconductor chip includes any one of an IC, a MOSFET, a SIC, a Schottky, and an IGBT.

Specifically, the thickness range of the metal base island 2 is 0.30 mm-0.51 mm.

Specifically, the metal bonding wire 3 includes any one of an aluminum wire, a copper wire, an aluminum tape, and a copper sheet.

Specifically, the width range of the pin 4 is 0.7 mm-0.9 mm, the length range is 1.4 mm-1.8 mm, and the thickness range is 0.30 mm-0.51 mm.

The semiconductor chip 1 will be described in detail as a MOSFET. Preferably, the metal bonding wire 3 is an aluminum wire with a wire diameter larger than 20 mils.

Specifically, the metal base island 2 is a whole piece of copper metal block, the upper surface of the metal base island is a core loading area, a V-shaped groove 6 is designed in an area, close to a side line, of the upper surface, the V-shaped groove has the advantages that the bonding performance of the metal base island 2 and the packaging body 5 can be improved, water vapor is prevented from entering the core loading area, protruding ear structures are designed on the left side and the right side of the metal base island 2, metal ejector pins of a plastic packaging mold are in contact with and press ears in the plastic packaging process, the metal base island 2 is guaranteed to be horizontal, and plastic packaging materials are prevented from overflowing to a lower surface cooling fin of the metal. Two through holes which are symmetrical left and right are arranged on the upper surface of the metal base island 2 and are close to the upper end, and the through holes are filled with the plastic package material 5 after plastic package, so that the effect of locking the plastic package material 5 and the lead frame is achieved. The lower surface of the metal base island 2 is designed in a stepped manner, the middle is thick, the edge is thin, after plastic package is completed, the middle area of the step is exposed out of the bottom surface of the plastic package material and is used as a radiating fin of a device, and the area of the radiating fin accounts for about 50% of the area of the bottom surface of the plastic package body.

Preferably, the number of the pins 4 is two.

Specifically, the pins 4 are located on the left side and the right side of the lower end of the packaging plastic package body 5, the part of the right side pin 4 extending towards the inside of the packaging plastic package body 5 is bent upwards to form a bonding area platform, the upper surface of the bonding platform is approximately flush with the front surface of the semiconductor chip 1, meanwhile, the right side pin extends leftwards to the right boundary infinitely close to the left pin 4, the extended bonding platform can contain a thick aluminum strip with the cross section area larger than 20 mils or a thicker aluminum strip or a large copper sheet for bonding, the structure of the pins 4 exposed out of the packaging plastic package body 5 is parallel to the bottom surface of the packaging plastic package body 5 and directly extends out without bending, the bottom surface is coplanar with the lower surface of the metal base island 2, and a small groove is. The two pin 4 substrates are designed TO be the same as the TO252 package pin substrate, and the application terminals can be directly used TO replace the TO252 package.

It should be noted that, according TO the known knowledge, the lower the resistance of the wire, the higher the electric and heat conduction efficiency, the bending length of the pin 4 packaged by the current mainstream TO252 is about 2.21mm, the sectional area of the pin is about 0.386mm2, the resistivity of copper is 17.2 (μ Ω. mm), and a formula is calculated according TO the resistance of the wire; and R = ρ L/S, and calculating the resistance =17.2 × 2.21/0.386mm2=98.476 (μ Ω. mm) of the current TO252 pin 4 bending part. The bending length of the pin 4 of the device structure is only about 0.2mm, the pin sectional area is about 0.323mm2, and the resistance =17.2 × 0.2/0.323mm 2= 10.65 (mu Ω. mm) of the bending part of the newly designed pin 4 is calculated. Compared with the current TO252 package, the resistance of the bending part of the pin 4 is reduced by more than about 9 times, and the electric and heat conduction efficiency of the part can be increased by about 9 times, namely the electric and heat conduction efficiency of the device is absolutely superior TO the current TO252 package.

In addition, the heat dissipation performance of the semiconductor device packaging structure of the embodiment of the invention is better than that of the current TO252 package. In order TO prove that the heat dissipation performance of the semiconductor device packaging structure provided by the embodiment of the invention is better than that of the current TO252 package, a simulation experiment is carried out.

Simulation principle: the heat dissipation performance of the device is simulated by using simulation software, a device model is set to be placed in an environment with a fixed convection heat transfer coefficient, and the junction temperature Tj (the junction temperature of the chip is known to lose efficacy when exceeding 175 ℃) of the surface of the semiconductor chip and the junction temperature of the surface Tc of the plastic package material are calculated through simulation by inputting a plurality of pairs of device input power parameters P, so that the thermal resistance Rthjc = (Tj-Tc)/P between the surface of the chip and the surface of the plastic package material can be calculated.

It should be noted that, as the name suggests, the thermal resistance is the resistance encountered by heat on the heat flow path, and is used for evaluating the heat dissipation performance of the electronic package product, and relates to the thermal reliability of a customer when using the product, and is an important parameter to be considered in the package design.

(1) Current TO252 package simulation process:

and a, establishing a three-dimensional model of the device, and inputting characteristic parameters of related materials.

a, setting the device model environment as 100W/m ℃ of convective heat transfer coefficient.

b, when the input power parameter is 3.4W, the chip surface is 175.8 ℃ obtained by simulation calculation.

And c, the surface junction temperature of the plastic package material of the synchronous detector is 154.3 ℃.

d, calculating a thermal resistance value Rthjc = (175.8-154.3)/3.4=6.32 ℃/W.

The simulation results are shown in fig. 15.

(2) The simulation process of the embodiment of the invention comprises the following steps:

and a, establishing a three-dimensional model of the device, and inputting characteristic parameters of related materials.

e, setting the device model environment as 100W/m ℃ of convective heat transfer coefficient.

f, when the input power parameter is 3.6W, the chip surface is 173 ℃ obtained by simulation calculation.

g, the surface junction temperature of the plastic package material of the synchronous detector is 163.6 ℃.

h, calculate thermal resistance value Rthjc = (173-163.6)/3.6=2.61 ℃/W.

The simulation results are shown in fig. 16.

The new design is obtained through simulation experiments, compared with the current design, the thermal resistance value is reduced by 3.71 ℃/W, the conversion proportion is 58.7%, the thermal resistance and the heat conduction capacity are in inverse proportion, and the heat dissipation performance of the new design is doubled under the same use environment.

As shown in fig. 1, 2, and 3, the thickness of the package 5 is less than 1.5mm, the thickness of the current mainstream TO252 package 5 is 2.3mm, and the thickness of the new invention device molding compound 5 is about 1mm thinner than the current design, which can be understood as that the heat conduction path through which the heat inside the molding compound 5 is transferred TO the surface of the package 5 is shortened by about 40% and the heat conduction efficiency of the device can be improved by about 40%, the package 5 has a transverse groove in the region of the back surface located between the pin 4 surface and the metal base island 2 surface, the width of the groove is about 1.6-1.8 mm, and the depth is about 0.05-0.08 mm, and when the application end is on the device upper board, red glue can be brushed in the groove TO prevent the device from falling off and shifting in the subsequent wave soldering process or reflow soldering process.

On the basis of the above examples, the present invention also provides an embodiment of bonding aluminum strips and copper sheets for higher power usage requirements, as shown in fig. 7 and 8.

As shown in fig. 9, the present invention also provides multiple pin implementations for different types of package formats, such as DFN5x 6.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.