CN204558442U - Semiconductor device and semiconductor device shell - Google Patents

Abstract

A semiconductor device and a case for the semiconductor device. Provided is a semiconductor device that does not cause poor appearance or lower adhesion to a cover even when a sealing material is injected up to the vicinity of the upper surface of a case. A semiconductor device (1) includes an insulating substrate (2), a semiconductor element (3) mounted on the insulating substrate (2), a hollow case (6) surrounding the periphery of the insulating substrate (2) to accommodate the semiconductor element (3), and A sealing material (10) that is filled into the casing (6) to seal the inside of the casing. The housing (6) has a protrusion (6f) partially protruding from an upper surface (6c) of the housing (6).

Description

Semiconductor device and case for semiconductor device

technical field

The utility model relates to a semiconductor device and a casing for the semiconductor device.

Background technique

As a semiconductor device, there is known a power semiconductor module in which one or more power semiconductor elements (semiconductor chips) are housed in a case, and the inside of the case is sealed with a sealing material. These power semiconductor elements use aluminum bonding wires or the like to electrically connect semiconductor chips mounted on an insulating substrate to circuits and terminals formed on the insulating substrate.

The sealing material inside the case is made of epoxy resin, etc., and is used to protect and insulate semiconductor chips and bonding wires housed in the case. Therefore, in the power semiconductor module, the sealing material is filled into the case to a height sufficient to cover and insulate the bonding wires inside the case. On the other hand, power semiconductor components are required to be miniaturized and thinned, and the height of the case is also expected to be reduced without hindrance. When injecting a liquid sealing material into the housing by using such a sealing material to achieve both insulation in the housing and miniaturization and thinning, the sealing material is injected up to the vicinity of the upper surface of the housing.

Since the sealing material is injected up to the vicinity of the upper edge of the case, the sealing material sometimes overflows to the upper surface of the case during injection. In addition, when the sealing material is transported after injection until the sealing material is cured, the sealing material may spread to the upper surface of the case.

This kind of sealing material spreads to the upper surface of the case and causes poor appearance of the power semiconductor module. In addition, when the case is covered with a cover and fixed by adhesive, the upper surface as the bonding surface of the case is not flat, which may cause sticking. reduced contact.

In order to prevent the sealing material from spreading to the upper surface of the case, a technique has been proposed in which a flange is provided on the inner surface of the case (Patent Document 1) and a step is provided on the inner surface of the case (Patent Document 2).

Patent Document 1: Japanese Patent Application Laid-Open No. 8-130291

Patent Document 2: Japanese Patent Application Laid-Open No. 4-354354

Utility model content

Problems to be solved by the utility model

However, since the flange and the stepped portion provided on the inner surface of the casing are formed toward the inside of the casing, the sealing material is prevented from reaching the upper surface of the casing in advance, but the injection amount of the sealing material is limited to the height at which the flange and the stepped portion are formed. . Therefore, the requirement to improve insulation by injecting the sealing material as far as possible up to the vicinity of the upper surface of the case is not sufficiently satisfied. In addition, it is assumed that in the case where the sealing material is injected up to the vicinity of the upper surface of the housing, it is difficult to prevent the sealing material from overflowing to the upper surface of the housing.

The present invention is advantageous in solving the above-mentioned problems of the conventional semiconductor device, and its object is to provide the following, even when the sealing material is injected up to the vicinity of the upper surface of the case, it will not cause poor appearance and reduce the adhesion with the cover. A semiconductor device and a case for a semiconductor device.

solutions to problems

In order to achieve the above object, the following semiconductor device and a semiconductor device case are provided.

A semiconductor device according to a first aspect of the present invention includes an insulating substrate, a semiconductor element mounted on the insulating substrate, a hollow case that surrounds the periphery of the insulating substrate to accommodate the semiconductor element, and a hollow case that is filled into the case to form the case. Inner seal sealing material. In addition, the case of the semiconductor device of the present invention has a protrusion partially protruding from the upper surface of the case.

A semiconductor device according to a second aspect of the present invention is the semiconductor device according to the first aspect, wherein the case has a box shape, and the protrusion is formed near a corner of an upper surface of the case.

A semiconductor device according to a third aspect of the present invention is the semiconductor device according to the first aspect or the second aspect, wherein the protrusion has a thickness obtained by dividing the thickness of the upper surface of the case.

A semiconductor device according to a fourth aspect of the present invention is the semiconductor device according to any one of the first to third aspects, wherein the protrusion formed near the longitudinal end of the case and the protrusion formed on the case The height from the above-mentioned upper surface is higher than the above-mentioned protruding portion in the vicinity of the central portion in the longitudinal direction.

A semiconductor device according to a fifth aspect of the present invention is the semiconductor device according to any one of the first to fourth aspects, wherein a stepped portion having a large thickness of the casing is provided on the inner surface of the casing, and a step is provided on the stepped portion. There is an end portion of the conductive member extending from the inside of the housing to the outside.

A sixth aspect of the present invention is the semiconductor device according to the fifth aspect, wherein the conductive member is a lead made of a copper plate, and the semiconductor device further includes a bonding wire connected to the lead.

A semiconductor device according to a seventh aspect of the present invention is the semiconductor device according to any one of the first to sixth aspects, further comprising a cover covering the case.

A semiconductor device according to an eighth aspect of the present invention is the semiconductor device according to any one of the first to sixth aspects, further comprising a flat plate placed on the case.

The semiconductor device case according to the ninth aspect of the present invention is a hollow case that surrounds the periphery of the insulating substrate to accommodate the semiconductor element and is filled with a sealing material, and has a protrusion that partially protrudes from the upper surface of the case.

A tenth aspect of the present invention is the case for a semiconductor device according to the ninth aspect, which has a box shape, and the protrusion is formed near a corner of the upper surface of the case.

In the semiconductor device case of the eleventh aspect of the present invention, in the semiconductor device case of the ninth or tenth aspect, the protrusion has a thickness obtained by dividing the thickness of the upper surface of the case.

The effect of utility model

In the semiconductor device of the present invention, protrusions are partially formed on the upper surface of the housing, and even if the sealing material spreads to the upper surface of the housing, it will not spread onto the protrusions. Therefore, appearance defects can be prevented. In addition, the flatness of the upper surface of the case can be maintained, thereby ensuring sufficient adhesiveness when bonding the upper surface of the case and the cover.

Description of drawings

FIG. 1 is a cross-sectional view of a power semiconductor module according to an embodiment of the present invention.

FIG. 2 is a top view of the power semiconductor assembly of FIG. 1 .

FIG. 3 is a cross-sectional view of the power semiconductor assembly of FIG. 1 .

FIG. 4 is a partially enlarged top view of the power semiconductor assembly of FIG. 1 .

5 is a cross-sectional view of a power semiconductor module provided with a cover.

6 is a plan view of a modified example of the power semiconductor module according to the embodiment of the present invention.

7 is a plan view of a modified example of the power semiconductor module according to the embodiment of the present invention.

FIG. 8 is a partially enlarged top view of the power semiconductor assembly of FIG. 6 .

FIG. 9 is a partially enlarged top view of the power semiconductor assembly of FIG. 7 .

Fig. 10 is a plan view of a power semiconductor module of a reference example.

FIG. 11 is a cross-sectional view of a conventional power semiconductor module.

FIG. 12 is a cross-sectional view of the power semiconductor assembly of FIG. 11 .

FIG. 13 is a partially enlarged top view of the power semiconductor assembly of FIG. 11 .

Explanation of reference signs

1: power semiconductor component; 2: insulating substrate; 3: semiconductor patch; 4: solder; 5: chip capacitor; 6: shell; 6c: upper surface; 6f: protrusion; 6g: protrusion; 6h: protrusion ; 7: insulating adhesive; 8: lead wire; 9: bonding wire; 10: sealing material; 11: cover.

Detailed ways

The semiconductor device and the case for semiconductor devices which concerns on embodiment of this invention are demonstrated concretely using drawing.

FIG. 1 shows a cross-sectional view of a power semiconductor module as a semiconductor device according to an embodiment of the present invention. The power semiconductor module 1 shown in FIG. 1 has a semiconductor chip 3 mounted on an insulating substrate 2 . The insulating substrate 2 includes a metal substrate 2a, an insulating plate 2b provided on the metal substrate 2a, and a metal foil 2c provided on the insulating plate 2b. The insulating plate 2b is made of a ceramic material such as silicon nitride, alumina, or aluminum nitride, or an organic insulating material such as epoxy resin. The metal foil 2c specifically refers to copper foil, for example. Metal foil 2c is selectively formed on insulating plate 2b, thereby forming a circuit pattern connected to electrodes formed on the lower surface of semiconductor chip 3 and leads described later.

The semiconductor chip 3 is electrically bonded to the wiring pattern constituted by the metal foil 2 c by bonding, for example, solder 4 as a bonding material. The semiconductor chip 3 is, for example, a chip diode or a chip transistor. As the chip transistor, an IGBT chip, a MOSFET chip, or the like can be used, and the type of the semiconductor chip 3 is not particularly limited. In addition, as the substrate of the semiconductor chip 3 , silicon carbide (SiC) and gallium nitride (GaN) can be used in addition to single crystal silicon. In FIG. 1 , an example in which the semiconductor chip 3 is a chip diode will be described. In addition, in FIG. 1, the case where one semiconductor chip 3 is mounted on the metal foil 2c of one insulating substrate 2 is illustrated, but two or more semiconductor chips 3 may be mounted on the metal foil 2c of one insulating substrate 2. slice 3.

In addition, in FIG. 1, the chip capacitor 5 is connected to the wiring pattern comprised by the metal foil 2c.

A case 6 is attached to the periphery of the insulating substrate 2 on which the semiconductor chip 3 is mounted. Specifically, the case 6 is a hollow (frame-shaped) substantially rectangular parallelepiped made of insulating resin such as PPS resin, and the upper end 6a is opened, and the sealing material 10 can be injected into the hollow space in the case 6 from the upper end 6a. The lower end portion 6 b of the case 6 is bonded to the metal substrate 2 a and the insulating plate 2 b of the insulating substrate 2 with an insulating adhesive 7 . Bonding with the insulating adhesive 7 ensures insulation between the insulating substrate 2 and the case 6 and eliminates a gap between the insulating substrate 2 and the case 6 to prevent the sealing material 10 from leaking out through the gap.

The casing 6 has a step portion 6da protruding inward in the middle of the height direction of the inner surface 6d. Due to the stepped portion 6da, the thickness of the casing 6 at the stepped portion 6da is thicker than the thickness of the casing 6 at the upper end portion 6a of the casing 6, that is, the distance between the inner surface 6d and the outer surface 6e of the casing 6. One end portion of the lead wire 8 made of a copper plate is exposed and attached to the stepped portion 6da. One end of the lead wire 8 exposed on the stepped portion 6 da of the inner surface 6 d of the case 6 is electrically connected to the metal foil 2 c of the insulating substrate 2 or the electrode of the semiconductor chip 3 through the bonding wire 9 .

The leads 8 and the case 6 are integrally formed by insert molding. The lead wire 8 extends in the thickness direction of the case 6 , and the other end portion is exposed outside the outer surface 6 e of the case 6 .

The inner space of the housing 6 is filled with a sealing material 10 for sealing components such as the semiconductor chip 3 . Examples of the sealing material 10 include a gel-like sealing material mainly composed of silicon and a sealing material made of a thermosetting resin such as epoxy resin. Among these examples of the sealing material 10, a sealing material made of a thermosetting resin is preferable because of its high insulation and high heat resistance. In this embodiment, a thermosetting resin is used for the sealing material 10, more specifically Said to use epoxy. However, this is not to exclude gel-like sealing materials. As for the sealing material 10 , a liquid sealing material 10 before curing is poured into the internal space from the opening of the upper end portion 6 a of the case 6 , and is cured by heating to seal the semiconductor chip 3 , the bonding wire 9 , and the like.

With regard to the injection amount of the sealing material 10, in order to ensure the insulation of the bonding wire 9, the sealing material 10 is injected so that the sealing material 10 can sufficiently cover the bonding wire 9, specifically so that the bonding wire 9 is covered by at least 1mm. high. On the other hand, in order to achieve miniaturization and thinning, the case 6 has a height as thin as possible within a range that does not interfere with insulation. Therefore, the sealing material 10 is injected in such a predetermined amount that the height of the sealing material 10 in the casing 6 reaches the vicinity of the upper surface 6 c of the casing 6 .

The power semiconductor module 1 of the present embodiment has a partial protrusion 6f on the upper surface 6c of the case 6 so that even if the sealing material 10 spreads due to the flow of the sealing material 10 when the sealing material 10 is injected, or vibration during transportation after injection, The upper surface 6c of the casing 6 also does not cause appearance defects.

The plan view shape of this protrusion part 6f is demonstrated using the plan view of FIG. 2. FIG. In addition, in FIG. 2, description of the semiconductor chip 3, the chip capacitor 5, the bonding wire 9, and the sealing material 10 is abbreviate|omitted for easy understanding of this invention. In the power semiconductor module 1 of the present embodiment, one protrusion 6f is separately formed at one corner of the case 6 at a position adjacent to the corner along the long-side direction and the short-side direction of the case. The housing 6 has four corners, so a total of eight protrusions 6f are formed.

Operation and effect of the power semiconductor module 1 of the present embodiment will be described with reference to FIGS. 3 and 4 . 3 is a cross-sectional view showing the situation when the sealing material 10 spreads to the upper surface 6c of the housing 6, and FIG. Even if the sealing material 10 overflows to the upper surface 6c of the housing 6 when the sealing material 10 is injected or when the sealing material 10 is injected and before curing, the sealing material 10 will go around the side of the protrusion 6f without spreading to the protrusion. The upper surface of 6f. Therefore, the power semiconductor module 1 of the present embodiment does not have appearance defects. In addition, the operability at the time of injecting the sealing material 10 can be improved.

Moreover, even when the sealing material 10 spreads to the upper surface 6c of the case 6, since the sealing material 10 does not spread to the protrusion 6f, the power semiconductor module 1 of this embodiment is mounted with the As shown in the perspective view in the case of the cover 11 , there is no reduction in the adhesiveness when the cover 11 is bonded and fixed.

In the power semiconductor module 1 of the present embodiment, from the viewpoint of being able to support the cover 11 flatly, the number of protrusions 6 f may be at least three. In consideration of the dimensional accuracy of the case 6 and the height accuracy of the protrusion 6f, in order to reliably support the cover 11, it is desirable that the corners are adjacent to the corners and along the long and short sides of the case as shown in FIG. 2 . Each side in the direction has a protrusion 6f.

In addition, it is desirable to set the position of the protrusion 6 f to a position where it does not interfere with the pressing jig when the bonding wire 9 is wire-bonded.

The height of the protrusion 6f from the upper surface 6c of the housing 6 is such that the protrusion 6f does not overflow even if the sealing material 10 overflows to the upper surface, and about 0.1 mm to 1 mm is sufficient. As a result of verification conducted by the inventors, the thickness of the sealing material 10 on the upper surface 6 c of the housing 6 is about 30 μm to 80 μm when the sealing material 10 spreads to the upper surface 6 c of the housing 6 . Therefore, if the height of the protrusion part 6f is about 0.1 mm or more, it can avoid that the sealing material 10 overflows on the protrusion part 6f. In addition, when the height of the protruding portion 6 f exceeds about 1 mm, there is little contribution to reducing the height of the housing 6 .

As shown in FIG. 1 , the case 6 has a shape in which the thickness below the stepped portion 6da is greater than the thickness of the upper end portion 6a. Therefore, when the case 6 is molded with a mold and the temperature is lowered to normal temperature, the amount of thermal contraction differs between the upper end portion 6 a and the lower end portion 6 b of the case 6 . As a result, the case 6 necessarily has a warped shape such that the center is convex in the longitudinal direction. The amount of warpage also depends on the size of the case, but the center portion is about 0.1 mm higher than the end portions in the longitudinal direction of the case.

In consideration of such warping of the case 6, it is preferable to provide the protrusion 6f near the end in the longitudinal direction of the upper surface 6c of the case 6 to support the cover 11 flatly on the case 6 and improve the adhesiveness. .

In addition, considering the warpage of the case 6, the height of the protrusion 6f provided near the longitudinal end of the upper surface 6c of the case 6 and the height of the protrusion provided near the longitudinal center of the upper surface 6c of the case 6 are adjusted. The height of the portion 6f is relatively high, and it is also easy to flatly support the cover 11 on the case 6 to improve the adhesiveness, which is preferable.

In the power semiconductor module 1 of the present embodiment, instead of the cover 11 , a flat plate (not shown) can be placed on the case 6 for mounting and laminating other components on the flat plate. Mounting and stacking other components on a flat panel enables high-density mounting. When a flat plate is placed on the case 6, in the case of conventional power semiconductor modules, if the sealing material spreads to the upper surface 6c of the case 6, it is difficult to ensure the flatness of the flat plate and the parallelism with the upper surface 6c of the case 6, and In contrast, the power semiconductor module 1 of this embodiment has the following effects: Even if the sealing material spreads to the upper surface 6c of the case 6, since the flat plate is supported by the protrusion 6f, the flatness of the flat plate and the upper surface of the case 6 can be ensured. Parallelism of surface 6c.

In addition, the power semiconductor assembly 1 with a flat plate mounted on the housing 6 can be used in the following structure: a spring is provided above the flat plate, and the metal substrate 2a of the power semiconductor assembly 1 is pressed and fixed to the metal substrate 2a by the force of the spring. The metal substrate 2a and the heat radiation fin are in contact with each other, thereby ensuring good contact between the metal substrate 2a and the heat radiation fin, thereby improving heat dissipation. In this case as well, the power semiconductor module 1 has the effect of being able to ensure the flatness of the flat plate and the parallelism with the upper surface 6 c of the case 6 .

Modifications of the protrusions of the case 6 will be described using the plan views of FIGS. 6 and 7 .

In the modified semiconductor device 21 shown in FIG. 6 , the protrusion 6g divides the upper surface 6c of the case 6 into two parts in the thickness direction, and the height on the outer surface 6e side is higher than that on the inner surface 6d side. The protrusion 6 g is not formed at the center in the longitudinal direction of the upper surface 6 c of the housing 6 . Since the protrusion 6g is not formed in the longitudinal center portion of the upper surface 6c of the case 6, the cover 11 is easily supported flatly against the above-mentioned warping of the case 6, thereby improving adhesiveness.

In the semiconductor device 31 of the modified example shown in FIG. 7, the position of the protrusion 6h on the upper surface 6c of the case 6 is substantially the same as that of the protrusion 6f shown in FIG. The direction is halved, and a protrusion 6 h is formed on the outer surface 6 e side of the case 6 .

The protrusion 6g shown in FIG. 6 and the protrusion 6h shown in FIG. 7 are different from the protrusion 6f shown in FIG. 2 in the shape of the protrusion, but the height of the protrusion can be set to the height of the protrusion 6f shown in FIG. same. In addition, considering the warpage of the case 6, the heights of the protrusions 6g, 6h provided near the ends in the longitudinal direction of the upper surface 6c of the case 6 can be adjusted to the height of the protrusions 6g and 6h provided near the center of the upper surface 6c of the case 6 in the longitudinal direction. The height of the protruding portions 6g, 6h is relatively high.

The operation and effect of the modification shown in FIG. 6 will be described using FIG. 8 , and the operation and effect of the modification shown in FIG. 7 will be described using FIG. 9 . FIG. 8 and FIG. 9 are schematic plan views showing the state when the sealing material 10 spreads over the upper surface 6 c of the case 6 in the case of these modified examples.

As can be seen from FIG. 8 and FIG. 9, the thickness of the protrusions 6g, 6h corresponds to the thickness of the upper surface 6c of the housing 6 after dividing the thickness, and since they are thin, even when the sealing material 10 is injected or the sealing material is injected After 10 and before curing, the sealing material 10 diffuses to the upper surface 6c of the casing 6, and the sealing material 10 also wraps around the sides of the protrusions 6g, 6h without spreading to the upper surfaces of the protrusions 6g, 6h. Therefore, the power semiconductor module 1 of the present embodiment does not have appearance defects. In addition, the operability at the time of injecting the sealing material 10 can be improved.

Furthermore, even if the sealing material 10 spreads over the upper surface 6c of the case 6, the sealing material 10 does not spread over the protrusions 6g, 6h, so that the adhesiveness of the cover 11 is not reduced.

A reference example of the protrusion of the case 6 will be described using the plan view of FIG. 10 .

The power semiconductor module 111 of the reference example shown in FIG. 10 has a protruding portion 106 g similar to that of the modified example shown in FIG. 6 . The protrusion 106g is a protrusion 106g that divides the upper surface 6c of the case 6 into two parts in the thickness direction and makes the height on the outer surface 6e side higher than that on the inner surface 6d side. This protruding portion 106g is different from the protruding portion 6g shown in FIG. 6 in that it is formed over the entire circumference on the upper surface 6c of the case 6 . Compared with the modified example shown in FIG. 6 , it is difficult for the protrusion 106 g of the reference example shown in FIG. 10 to support the cover 11 flatly on the warped case 6 as described above, and the improvement of adhesiveness is weak.

As a comparative example, a conventional power semiconductor module 101 will be described using the cross-sectional view shown in FIG. 11 . In addition, in FIG. 11, the same code|symbol is attached|subjected to the same component as the power semiconductor module 1 shown in FIG. 1, and repeated description is abbreviate|omitted below.

The difference between the conventional power semiconductor module 101 shown in FIG. 11 and the power semiconductor module 1 according to the embodiment of the present invention shown in FIG. . The case 106 differs from the case 6 in that it does not have the protruding portion 6 f formed on the case 6 of the power semiconductor module 1 according to the embodiment of the present invention shown in FIG. 1 , and the other structures are the same.

In FIG. 12 , the state in which the sealing material 10 is injected into the inner space of the housing 106 of the above-mentioned conventional semiconductor package 101 and the sealing material 10 spreads to the upper surface of the housing 106 is shown in a cross-sectional view. FIG. 13 shows the top view of FIG. 12 Partial schematic. If the sealing material 10 spreads to the upper surface of the case 106 as shown in FIGS. 12 and 13 , when the cover 11 is placed on the case 106, the cover 11 will not be supported flatly, and the adhesion during adhesive fixation will be difficult. The contact property is deteriorated, and the appearance is poor.

Claims (11)

1. a semiconductor device, is characterized in that, possesses:

Insulated substrate;

Semiconductor element, it is mounted on this insulated substrate;

The shell of hollow, its periphery surrounding this insulated substrate is to accommodate this semiconductor element; And

Encapsulant, it is filled in this shell and seals in this shell,

Further, this shell has from the outstanding jut in the upper surface local of this shell.

2. semiconductor device according to claim 1, is characterized in that,

Above-mentioned shell has box shape, and above-mentioned jut is formed in the adjacent corner of the upper surface of this shell.

3. semiconductor device according to claim 1 and 2, is characterized in that,

Above-mentioned jut has the thickness of the upper surface splitting above-mentioned shell and the thickness obtained.

4. semiconductor device according to claim 1 and 2, is characterized in that,

Above-mentioned jut near the long side direction end being formed in above-mentioned shell is compared with the above-mentioned jut near the long side direction central portion being formed in above-mentioned shell, and the height from above-mentioned upper surface is higher.

5. semiconductor device according to claim 1 and 2, is characterized in that,

Possess the large stage portion of the thickness of this shell at the inner surface of above-mentioned shell, be provided with an end of the conductive component extended outward in shell in this stage portion.

6. semiconductor device according to claim 5, is characterized in that,

Above-mentioned conductive component is the lead-in wire be made up of copper coin, and this semiconductor device also possesses the closing line be connected with this lead-in wire.

7. semiconductor device according to claim 1 and 2, is characterized in that,

Also possesses the lid covering above-mentioned shell.

8. semiconductor device according to claim 1 and 2, is characterized in that,

Also possesses the flat board be positioned on above-mentioned shell.

9. a semiconductor device shell, be surround insulated substrate periphery to accommodate semiconductor element and to be filled the shell of the hollow of encapsulant, the feature of this semiconductor device shell is,

Have from the outstanding jut in the upper surface local of this shell.

10. semiconductor device shell according to claim 9, is characterized in that,

Have box shape, above-mentioned jut is formed in the adjacent corner of the upper surface of above-mentioned shell.

11. semiconductor device shells according to claim 9 or 10, is characterized in that,

Above-mentioned jut has the thickness of the upper surface splitting above-mentioned shell and the thickness obtained.