JP2008135788A - Semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a semiconductor device that can be small-sized and without the shorting between a chip component and a cap. <P>SOLUTION: The semiconductor device or the like is provided with a substrate including a first plane, having a cavity and a second substrate having a second plane facing the first plane; a semiconductor chip disposed in the cavity and connected electrically to the substrate; a chip component disposed on the second plane of the substrate and connected electrically with the substrate, a heat sink disposed on the second plane of the substrate and transmitting the heat from the semiconductor chip, a conductive cap covering the second plane of the substrate engaged with the substrate and connected with the heat sink, and an insulating body formed on the opposite plane of the chip component of the cap. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor device in which components are mounted on a substrate surface and heat is radiated from a cap disposed above the component.

  Conventionally, a semiconductor module having components mounted on the surface of a multilayer substrate is known. In such a semiconductor module, it is necessary to mount components with an efficient mounting area. Therefore, there is a semiconductor module in which a cavity is provided on the back surface of the back surface of the multilayer substrate, and a semiconductor chip is disposed in the cavity. Such a semiconductor module has a heat sink on the surface of the multilayer substrate opposite to the semiconductor chip across the substrate, and the heat sink is bonded to the cap of the semiconductor module. Since the cap is formed of a metal having high thermal conductivity, the heat generated by the semiconductor chip is dissipated through the heat sink and the cap, thereby allowing the semiconductor module to operate stably.

  In recent years, there has been an increasing demand for miniaturization of products such as mobile phones, and as a result, there is a need to further miniaturize semiconductor modules such as power amplifier modules.

  In the structure of the conventional semiconductor module, the module cannot be reduced in size because the heat sink for heat dissipation is large. The reason is that if the heat sink and the cap are made small to suppress the height of the module, the cap and the chip component may be short-circuited.

  For example, consider a case where the heat sink is changed from the 1608 type (1.6 mm × 0.8 mm) to the 1005 type (1.0 mm × 0.5 mm) that can be handled by a bulk feeder. In this case, the heat sink is at the same level as other 1005 chip parts (for example, L, C, R), and depending on the tolerance of the chip parts, the cap and the chip parts may be electrically short-circuited. is there. Here, “tolerance” refers to the difference between the maximum value and the minimum value of dimensions allowed in the standard.

  A method of changing all the chip parts to 0603 type (0.6 mm x 0.3 mm) is also conceivable. However, with the 0603 type, there are parts that do not provide the required characteristics, which increases costs. Further, heat can be radiated through, for example, a mold without using a cap. However, current products are required to have shielding properties that prevent leakage of power and influence on peripheral components. In order to provide the shielding property, another configuration is required. As a result, the size cannot be reduced, and the cost increases.

  An object of the present invention is to provide a semiconductor device having a structure in which a chip component and a cap do not short-circuit and can be miniaturized.

  A first semiconductor device according to the present invention includes a first surface having a cavity, a substrate having a second surface opposite to the first surface, and a substrate disposed in the cavity. Connected to the semiconductor chip, a chip component disposed on the second surface of the substrate, and electrically connected to the substrate; and disposed on the second surface of the substrate; A heat sink that transmits, a conductive cap that fits over the substrate to cover the second surface of the substrate and is joined to the heat sink, and an insulator provided on a surface of the cap facing the chip component; It has. This achieves the above object.

The insulator may be provided in a stripe shape on the cap.
The insulator may be provided on the entire surface of the cap except for a region to be joined to the heat sink.
The insulator may be provided on the entire surface of the cap.
The cap may have a fitting claw that fits with the substrate, and the insulator may be provided on a portion of the cap other than the fitting claw.
The cap may have a fitting claw for fitting with the substrate, and the insulator may also be provided on the fitting claw.
The insulator may be a thermosetting resin.

  A second semiconductor device according to the present invention includes a first surface having a cavity, a substrate having a second surface opposite to the first surface, and a substrate disposed in the cavity. Connected to the semiconductor chip, a chip component disposed on the second surface of the substrate, and electrically connected to the substrate; and disposed on the second surface of the substrate; A heat sink for transmitting, and a conductive cap that fits over the substrate to cover the second surface of the substrate and joins the heat sink, the cap at the outer edge of the region that joins the heat sink, It is bent in the direction of the substrate. This achieves the above object.

  A hole may be formed in a portion of the cap that joins the heat sink, and the hole may be filled with an adhesive that transmits heat.

  The chip part may be a filletless part.

  Embodiments 1 to 3 of the present invention will be described below with reference to the accompanying drawings. In the drawings, the same reference numerals are assigned to components having the same or similar functions. A semiconductor module described in the following embodiments is a power amplifier module, a small high-frequency module, or the like.

(Embodiment 1)
FIG. 1 is a perspective view of a semiconductor module 100 according to the first embodiment. The semiconductor module 100 is formed by fitting a cap 10 on a multilayer substrate 30. As will be described later, the back surface of the multilayer substrate 30 is provided with a cavity, that is, a cavity or a recess from the back surface of the substrate, and a semiconductor chip (not shown) is provided there. On the other hand, a heat sink 20 is provided on the opposite side of the multilayer substrate 30 of the semiconductor chip. A cap soldering material 40 is applied on the heat sink 20 to physically fix the heat sink 20 and the cap 10. As a result, heat generated from the semiconductor chip is transmitted to the surface of the multilayer substrate 30 and is released to the outside through the heat sink 20, the cap soldering material 40, and the cap 10.

  The main feature of the semiconductor module 100 is that an insulating film 11 is attached to the back surface (opposite the outer surface) of the cap 10. More specifically, the cap 10 is formed of a metal having a high thermal conductivity such as copper or aluminum in order to function as a shield that prevents leakage of power and prevents influence on peripheral components, and to improve heat dissipation performance. Has been. Therefore, if the cap 10 is short-circuited with a chip component (not shown) on the multilayer substrate 30, element destruction and overheating occur, which is dangerous and the original performance cannot be exhibited. Therefore, the insulating film 11 is attached to the back surface of the cap 10 and facing the multilayer substrate 30 to prevent a short circuit between the chip component (not shown) and the cap 10. The insulating film 11 is pasted on, for example, a strip-shaped portion including a region facing the chip component 80. The insulating film 11 may be a known material such as an epoxy resin (for example, Obiwan Coat), which is a thermosetting resin, or a polyimide resin (PIMET, Sumitomo Electric). However, since the cap soldering material 40 on the heat sink 20 needs to be in direct contact with the cap 10, no insulating film is attached to the strip-shaped region above the heat sink 20. Note that the thickness of the insulating film is, for example, 50 to 200 μm.

  FIG. 2 is a cross-sectional view of the semiconductor module 100 taken along the line A-A ′ of FIG. 1. As is apparent from the figure, the semiconductor module 100 has components (SMD: Surface Mount Device) mounted on the multilayer substrate 30 and is formed by fitting the cap 10 into the multilayer substrate 30 as a shield. A cavity is provided on the back side of the multilayer substrate 30, and the semiconductor chip 50 is electrically connected to the multilayer substrate 30 by bonding wires 60. When the connection is secured by the bonding wire 60, the cavity is filled with the potting material 70, and the semiconductor chip 50 is sealed.

  The insulating film 11 is interposed between the cap 10 and the chip component 80 provided on the multilayer substrate 30. Thereby, a short circuit can be prevented. Further, it is understood that the insulating film 11 is not attached to the region above the heat sink 20 and the cap soldering material 40 is fixed in direct contact with the cap 10. On the line where the insulating film 11 is not applied, a component that is the same height as the heat sink or a component that is higher than the heat sink cannot be mounted depending on the component tolerance, but if the height is lower than that, the chip component 80 is mounted. May be. A component soldering material 41 is used to connect the multilayer substrate 30 and the heat sink 20 and between the multilayer substrate 30 and the chip component 80.

  If the size of the heat sink 20 is reduced from the 1608 type (1.6 mm x 0.8 mm) to the 1005 type (1.0 mm x 0.5 mm, height 0.5 mm ± 0.05 mm), the 1005 type inductor (height 0.45 mm ± 0.05 mm) ) Can be used. This is because the presence of the insulating film 11 eliminates the possibility of a short circuit. Thereby, the distance between the chip component 80 and the cap 10 can be reduced. At the same time, since the mounting area of the heat sink 20 and the size in the height direction can be reduced, the height of the semiconductor module 100 in the direction perpendicular to the multilayer substrate 30 can also be reduced. Therefore, the size of the entire semiconductor module 100 can be reduced.

  FIG. 3 is a development view of the cap 10. 2 is obtained by bending in the same direction along the dotted line. The insulating film 11 is attached to both sides of the cap 10. The cap soldering material 40 is connected to the cap 10 in the strip-shaped portion 9 between the insulating films 11. That is, the insulating film 11 is affixed on the stripe on the back surface of the cap 10. Affixing the insulating film 11 in a stripe shape is very simple and can be realized at a low cost. In this example, the insulating film 11 is not attached to the fitting claws 12 of the cap 10 for fitting the cap 10 into the multilayer substrate 30. As a result, the solder crawls up to the back surface of the cap fitting claw at the time of customer mounting, and an increase in mounting strength can be expected.

  FIG. 4 is a development view of the cap 10 according to the second example of attaching the insulating film 11. The difference from FIG. 3 is that the insulating film 11 is also stuck to the fitting claws 12 of the cap 10. According to this, the same advantage as the case shown in FIG. 3 can be obtained. It is further advantageous that it is not necessary to be aware of the accuracy of the stripe outer periphery as compared with the case where the insulating film 11 must be pasted except for the fitting claw 12 portion. Therefore, the insulating film 11 can be affixed at a lower cost, and thus the cap can be manufactured at a lower cost.

  FIG. 5 is a cross-sectional view of the semiconductor module 100 according to a second example of attaching the insulating film 11. The insulating film 11 is pasted up to the fitting claws 12 of the cap 10, but there is no influence on the operation of the semiconductor module 100 due to this. The multilayer substrate 30, the component soldering material 41, the semiconductor chip 50, the bonding wire 60, the potting material 70, and the chip component 80 are exactly the same as in FIG. Therefore, these descriptions are omitted.

  FIG. 6 is a development view of the cap 10 according to the third example of attaching the insulating film 11. The insulating film 11 is affixed to the cap 10 in all regions except the region 9 where the cap soldering material 40 and the cap 10 contact. In other words, the insulating film 11 in which the region 9 portion where the cap soldering material 40 and the cap 10 are in contact with each other is cut out is pasted. According to this, not only the same advantage as the case shown in FIG. 3 can be obtained, but also a portion that can be insulated can be widened, and the degree of design freedom can be increased. Note that the region 9 may not be a region where the cap soldering material 40 and the cap 10 strictly contact with each other, and may be appropriately changed if necessary in manufacturing.

(Embodiment 2)
In the second embodiment, a semiconductor module in which a cap soldering material on a heat sink comes into contact with a cap via an insulating film to radiate heat will be described.

  FIG. 7 is a development view of the cap 10 with the insulating film 11 attached to the entire surface. Region 9 is a position corresponding to the upper side of the heat sink. An insulating film 11 is also attached to the region 9. An insulating film 11 is also attached to the fitting claw 12 of the cap 10.

  FIG. 8 is a cross-sectional view of the semiconductor module 102 according to the second embodiment. The semiconductor module 102 differs from the semiconductor module of FIG. 2 in the structure of the portion between the cap 10 and the heat sink 20. Below, only the said different part is demonstrated. The multilayer substrate 30, the component soldering material 41, the semiconductor chip 50, the bonding wire 60, the potting material 70, and the chip component 80 are exactly the same as in FIG. Therefore, these descriptions are omitted.

  In the second embodiment, the insulating film 11 and the thermosetting resin 40 are provided between the cap 10 and the heat sink 20 in order from the cap 10 side. The thermosetting resin 40 is provided in place of the cap soldering material. The thermosetting resin 40 also has high heat transfer performance and is sufficient to transfer the heat transferred from the heat sink 20 to the cap 10. In this example, since the insulating film 11 is attached to the entire surface of the cap 10, the processing step of the insulating film 11 can be omitted as compared with the case where the insulating film 11 is attached excluding the position above the heat sink. Therefore, the cap 10 can be manufactured easily and inexpensively. In addition, as in the first embodiment, it is possible to achieve component contact, heat dissipation performance, and reduction in component size.

  In this example, since the insulating film 11 is also attached to the fitting claws 12 of the cap 10, it is not necessary to consciously improve the accuracy of attaching the insulating film, and the cap 10 can be manufactured more easily and inexpensively. Needless to say, however, the component contact, the heat radiation performance, and the component size can be reduced without attaching the insulating film 11 to the fitting claws 12. FIG. 9 is a development view of the cap 10 with the insulating film 11 attached to the entire surface other than the fitting claws 12. As shown in the drawing, in order to attach the insulating film 11, it is necessary to improve the attaching accuracy of the insulating film 11. However, since the insulating film 11 does not exist, solder rises on the back surface of the cap fitting claw 12 at the time of customer mounting, and an increase in mounting strength can be expected.

(Embodiment 3)
In Embodiment 3, a semiconductor module having a cap in which a portion to be joined to a heat sink is recessed will be described. By recessing the cap, there is no need to provide the insulating film described in the first and second embodiments.

  FIG. 10 is a perspective view of the semiconductor module 110 according to the third embodiment. As shown in the figure, the cap 10 is provided with a recessed portion (recess) 13 bent from the periphery to the multilayer substrate 30 side and retracted. Hereinafter, this recess is referred to as a cap recess 13. The cap recessed part 13 is located above the heat sink (not shown) located in the lower part.

  FIG. 11 is a cross-sectional view of the semiconductor module 110 taken along the line A-A ′ of FIG. 10. The semiconductor module 110 is different from the semiconductor module of FIG. 2 in that the structure of the cap 10 and that the insulating film 11 is not attached to the cap 10 of the semiconductor module 110. Below, only the said different part is demonstrated. The multilayer substrate 30, the component soldering material 41, the semiconductor chip 50, the bonding wire 60, the potting material 70, and the chip component 80 are exactly the same as in FIG. Therefore, these descriptions are omitted.

  As is apparent from the figure, the cap 10 has a cap recess 13 above the heat sink 20. More specifically, the outer edge of the region joined to the heat sink is bent toward the substrate. The clearance above the heat sink 20 can be adjusted by the amount of retreat (bending amount) from the surface of the cap recess 13. For example, when the retraction amount of the cap recess 13 is 0.05 mm from the surface of the cap 10, the height of the heat sink 20 is 0.5 ± 0.05 mm, and the height of the inductor which is the peripheral chip component 80 is 0.45 ± 0.05 mm. A minimum clearance of 0.05mm can be earned. Conversely, if the amount of retreat from the surface of the cap recess 13 is increased, the height of the heat sink 20 can be decreased accordingly. Thereby, the heat sink 20 can be reduced in size, and a short circuit between the cap 10 and the chip component 80 can be avoided. By using such a cap 10, for example, it is not necessary to attach the insulating film 11 like the cap 10 of FIG.

  FIG. 12 is a perspective view of a semiconductor module 120 according to another example of the third embodiment. Unlike the cap recess 13 (FIG. 10), the cap 10 of the semiconductor module 120 has a hole. The figure shows a state in which the adhesive 40 is injected into the hole up to the surface of the cap 10.

  FIG. 13 is a cross-sectional view of the semiconductor module 120 taken along the line A-A ′ of FIG. 12. The semiconductor module 120 is different from the semiconductor module of FIG. 11 in the structure of the cap 10. Below, only the said different part is demonstrated. The multilayer substrate 30, the component soldering material 41, the semiconductor chip 50, the bonding wire 60, the potting material 70, and the chip component 80 are exactly the same as in FIG. Therefore, these descriptions are omitted.

  As shown in the figure, the cap 10 of the semiconductor module 120 is perforated in a region corresponding to the upper portion of the heat sink 20. This hole is obtained by removing the bottom of the cap recess 13 (FIG. 11) and extends from the upper surface of the heat sink 20 to the surface of the cap 10. By providing the hole, the adhesive 40 can be dispensed from the upper surface of the cap and filled with the adhesive, so that the manufacturing efficiency can be improved. Furthermore, even when the adhesive 40 is dispensed excessively, scraping can be easily performed, so that the working efficiency is increased, and thus the manufacturing efficiency can be improved. In addition, since the cap 10 only remove | eliminated the bottom part of the cap recessed part 13 (FIG. 11), the advantage at the time of providing the cap recessed part 13 already demonstrated can be acquired as an advantage of this modification as it is.

  The embodiment of the present invention has been described above. In the first and second embodiments, an insulating film is provided on the cap facing the chip component in order to avoid a short circuit between the cap and the chip component. However, the configuration is not limited to this configuration as long as a short circuit can be avoided. For example, a non-conductive and thermosetting resin that conducts heat may be applied to the substrate (chip component) and the cap may be adhered. Furthermore, such a resin may be filled not only on the chip component but also between the cap 10 and the multilayer substrate 30. The resin also functions as an adhesive that bonds the cap 10 and the multilayer substrate 30 together. FIG. 14 is a cross-sectional view of a semiconductor module 140 according to a modification of the first and second embodiments. The semiconductor module 140 is formed by filling the surface of the multilayer substrate 30 and / or the chip component 80 facing the cap 10 with a nonconductive resin (adhesive) 42. The adhesive is, for example, a thermosetting resin such as an epoxy resin. The cap 10 is fixed in direct contact with a non-conductive resin. According to this structure, since non-conductive resin is sandwiched between the cap 10 and the chip component 80, there is no fear of electrical short circuit. Further, since the heat generated in the semiconductor chip 50 is directly transmitted to the cap 10 through the nonconductive resin, the heat sink can be omitted. Therefore, the external size of the semiconductor module 140 can be very small.

  Moreover, the semiconductor module can be further reduced in size by making all the chip parts 80 filletless parts. Here, the “fillet” refers to a solder pile or shape extending from the top to the bottom when the electrode terminal of the component and the mounting land are soldered. Therefore, the “filletless part” means a part without such solder. FIG. 15 is a view showing a semiconductor module 130 using the filletless chip component 81. In this figure, the multilayer substrate 30, the component soldering material 41, the semiconductor chip 50, the bonding wire 60, and the potting material 70 are exactly the same as in FIG. Therefore, these descriptions are omitted. By using the filletless component, the electrode terminal and the cap do not come into contact with each other, and unnecessary solder piles are eliminated, so that the cap can be lowered and a short circuit can be prevented. Further, since the land width or land area can be reduced, the mounting area of the chip component 80 can be reduced. As a result, the size of the semiconductor module can be reduced by simply reducing the size of the conventional cap and heat sink without providing an insulating film on the cap. Moreover, if a filletless component is used in the semiconductor modules of the first to third embodiments described so far, the advantages of the first to third embodiments can be obtained, and further downsizing can be promoted.

[The invention's effect]
Since the insulator is provided between the conductive cap that covers the substrate and the chip component, there is no possibility that the chip component and the cap are short-circuited. As a result, the distance between the cap and the chip component can be reduced, and the size of the semiconductor device can be reduced. At this time, the size of the semiconductor device can be reduced more effectively by reducing the size of the heat sink. The insulator is, for example, a thermosetting resin.

  Since the insulator is provided in a stripe shape on the cap, the attachment of the insulator to the cap becomes very simple, and therefore can be realized at low cost.

  The insulator is provided on the entire surface excluding a region where the cap is bonded to the heat sink. Thereby, the part which can be insulated can be taken widely and the freedom degree of design can also be made high.

  Since the insulator is provided on the entire surface of the cap, it can be attached only by processing the outer peripheral portion of the insulator. That is, the insulator processing steps are simplified. Therefore, the cap can be manufactured easily and inexpensively.

  The insulator is provided in a portion other than the fitting claw of the cap. As a result, when the customer mounts, the solder also crawls up on the cap fitting claw, and the mounting strength increases.

  The insulator is also provided on the portion of the cap where the claw is formed. Thereby, the process of an insulator is simplified. Therefore, the cap can be manufactured easily and inexpensively.

  Since the thermosetting resin is provided at the position of the chip component facing the cap, there is no possibility that the chip component and the cap are short-circuited. As a result, the distance between the cap and the chip component can be reduced, and the size of the semiconductor device can be reduced.

  The cap is bent toward the substrate at the outer edge of the region where the cap is joined to the heat sink. A short circuit between the cap and the chip component can be avoided without providing an insulating film between the cap and the chip component.

  A hole is formed in a region of the cap that joins the heat sink, and the hole is filled with an adhesive that transfers heat. Since the adhesive can be dispensed and filled from the upper surface of the cap to the hole, the manufacturing efficiency can be improved.

  By making the chip component filletless, unnecessary solder piles on the chip component are eliminated. Therefore, a short circuit can be prevented and the mounting area of the chip component can be reduced.

1 is a perspective view of a semiconductor module according to a first embodiment. It is sectional drawing of the semiconductor module cut | disconnected by the A-A 'line | wire of FIG. It is an expanded view of a cap. It is an expanded view of the cap by the 2nd example of attachment of an insulating film. It is sectional drawing of the semiconductor module by the 2nd example of attachment of an insulating film. It is an expanded view of the cap by the 3rd example of affixing an insulating film. It is an expanded view of the cap which stuck the insulating film on the whole surface. FIG. 6 is a cross-sectional view of a semiconductor module according to a second embodiment. It is an expanded view of the cap which affixed the insulating film on the whole surface other than a fitting nail | claw. FIG. 6 is a perspective view of a semiconductor module according to a third embodiment. It is sectional drawing of the semiconductor module cut | disconnected by the A-A 'line | wire of FIG. 12 is a perspective view of a semiconductor module according to another example of Embodiment 3. FIG. It is sectional drawing of the semiconductor module cut | disconnected by the A-A 'line | wire of FIG. FIG. 6 is a cross-sectional view of a semiconductor module according to a modification of the first and second embodiments. It is a figure which shows the semiconductor module using a filletless chip component.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Cap 11 Insulation film 20 Heat sink 30 Multilayer board 40 Cap soldering material 41 Component soldering material 50 Semiconductor chip 60 Bonding wire 70 Potting material 80 Chip component 100 Semiconductor module

Claims (7)

A first surface having a cavity, and a substrate having a second surface opposite the first surface;
A semiconductor chip disposed in the cavity and electrically connected to the substrate;
A chip component disposed on the second surface of the substrate and electrically connected to the substrate;
A heat sink disposed on the second surface of the substrate and connected to the substrate by a soldering material for transferring heat of the semiconductor chip;
A conductive cap that fits over the substrate to cover the second surface of the substrate and is joined to the heat sink;
An insulator provided on a surface of the cap facing the chip component;
The semiconductor device, wherein the cap and the heat sink are directly fixed by a soldering material.   The semiconductor device according to claim 1, wherein the insulator is provided in a stripe shape on the cap.   The semiconductor device according to claim 1, wherein the insulator is provided on an entire surface of the cap excluding a region bonded to the heat sink.   The said cap has the fitting nail | claw which fits with the said board | substrate, and the said insulator is provided in parts other than the said fitting claw of the said cap. Semiconductor device.   The semiconductor device according to claim 1, wherein the cap has a fitting claw that fits with the substrate, and the insulator is also provided on the fitting claw.   The semiconductor device according to claim 1, wherein the insulator is a thermosetting resin.   The semiconductor device according to claim 1, wherein the chip component is a filletless component.

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