Semiconductor device

Abstract

A semiconductor device is comprising: a semiconductor chip; a substrate on which the semiconductor chip is mounted; and a sealing resin covering the portion of the substrate on which the semiconductor chip is mounted. Furthermore, on a second main surface opposite to the surface on which the semiconductor chip is mounted, the sealing resin has a plurality of holes extending through the second main surface of the substrate.

Description

Technical Field

[0001] This invention relates to a semiconductor device. Background Technology

[0002] In recent years, with the increasing integration and speed of LSI (Liquid Crystal Sensor) technology, the heat generated by semiconductor chips in resin-sealed packages such as QFP (Quad Flat Package) has increased. The heat generated within the semiconductor chip can sometimes adversely affect the lifespan of the component and the package itself, reducing reliability and potentially leading to component failure. Furthermore, the increase in capacitance and miniaturization resulting from product serialization inevitably leads to an increase in the heat generated by the semiconductor chip. Therefore, improving the heat dissipation of semiconductor chips within packaged semiconductor devices has become an important research topic.

[0003] As one measure to improve heat dissipation, a structure in which a metal heat sink is attached to the semiconductor device within the package structure has been proposed (see, for example, Patent Document 1 and Patent Document 2). In this structure, a heat sink is attached to the back side of a substrate on which a semiconductor chip is mounted. Furthermore, the back side of the heat sink is exposed on the bottom surface of the package body. With this structure, heat from the semiconductor device is released to the outside of the package through the heat sink.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 06-097323

[0007] Patent Document 2: International Publication No. 2016 / 092938 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, in the technologies described in Patent Documents 1 and 2, the area on the back side of the substrate housing the semiconductor chip that is not sealed with resin is formed to accommodate the heat sink. Therefore, the uneven stress caused by the difference in the amount of sealing resin on both sides of the substrate can lead to warping of the package structure, raising concerns about adverse effects on the semiconductor chip. Furthermore, moisture intrusion into the unsealed area from the outside could also negatively impact the semiconductor chip. Therefore, in semiconductor devices with existing package structures, sufficient heat dissipation cannot be achieved, thus compromising reliability.

[0010] To address the aforementioned problems, the present invention provides a semiconductor device with excellent reliability.

[0011] Furthermore, the above-mentioned and other objectives of the present invention, as well as the novel features of the present invention, become clear from the description and drawings herein.

[0012] Methods for solving problems

[0013] The semiconductor device of the present invention includes: a semiconductor chip; a substrate on which the semiconductor chip is mounted; and a sealing resin covering the portion of the substrate on which the semiconductor chip is mounted. Furthermore, on the second main surface side opposite to the mounting surface of the semiconductor chip, the sealing resin has a plurality of holes extending through the second main surface of the substrate.

[0014] Invention Effects

[0015] According to the present invention, a semiconductor device with excellent reliability can be provided.

[0016] Furthermore, the issues, structures, and effects other than those described above will be clarified through the following description of the implementation methods. Attached Figure Description

[0017] Figure 1 It is a diagram showing the structure of an existing semiconductor device.

[0018] Figure 2 This is a diagram illustrating the structure of a semiconductor device according to an embodiment of the present invention.

[0019] Figure 3 yes Figure 2 An enlarged view of the semiconductor chip and the surrounding area of ​​the heat-conducting components of the semiconductor device shown.

[0020] Figure 4 This is a diagram showing the structure of the sealing resin on the back side of the substrate of a semiconductor device.

[0021] Figure 5 This is a diagram showing the structure of the sealing resin on the back side of the substrate of a modified semiconductor device.

[0022] Figure 6 This is a diagram showing the structure of the sealing resin on the back side of the substrate of a modified semiconductor device.

[0023] Figure 7 This is a diagram showing the structure of the sealing resin on the back side of the substrate of a modified semiconductor device. Detailed Implementation

[0024] Hereinafter, an example of a semiconductor device according to an embodiment of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the following example. In the figures described below, common components are labeled with the same reference numerals. Furthermore, in the drawings used in this specification, the same or corresponding components are labeled with the same reference numerals, and sometimes repeated descriptions of these components are omitted.

[0025] In addition, the explanation will proceed in the following order.

[0026] 1. Overview of existing semiconductor device structures

[0027] 2. Implementation methods of semiconductor devices

[0028] 3. Modifications of semiconductor devices

[0029] <1. Overview of Existing Semiconductor Device Structures>

[0030] [Structure of existing semiconductor devices]

[0031] Before describing the structure of the semiconductor device of the present invention, the structure and problems of existing semiconductor devices will be described. Figure 1 This indicates the structure of existing semiconductor devices.

[0032] Figure 1 This is a side view showing the mounting structure of the semiconductor device 100 with its package structure. Figure 1 The semiconductor device 100 shown includes a semiconductor chip 10, a substrate 20, a sealing resin 30, a heat conduction component 40, and a heat dissipation component 50. The semiconductor chip 10 is mounted on the surface (first side) of the substrate 20.

[0033] Furthermore, a sealing resin 30 is formed in a shape that covers the semiconductor chip 10 and the area of ​​the substrate 20 on which the semiconductor chip 10 is mounted. In addition, the semiconductor device 100 of the package structure bonds the sealing resin 30 to the heat dissipation component 50 through a heat conduction component 40 formed on the entire surface of the sealing resin 30 on the back side (second side).

[0034] To protect the semiconductor chip 10 from moisture, dust, and other contaminants, the semiconductor device 100 has a package structure in which a portion of a substrate 20 and the semiconductor chip 10 are sealed with a sealing resin 30. Furthermore, heat generated by the semiconductor chip 10 is released to the outside from the heat dissipation component 50 via the sealing resin 30 and the heat conduction component 40.

[0035] In a semiconductor device 100 with such a package structure, the sealing resin 30 is required to have a certain thickness in order to protect the semiconductor chip 10 from external deterioration factors and, in order to ensure the voltage resistance of the semiconductor device 100. Therefore, the semiconductor device 100 with the package structure has a sealing resin 30 of a certain thickness from the heat-generating semiconductor chip 10 to the heat conduction component 40 and the heat dissipation component 50 for heat dissipation.

[0036] As a result, in the semiconductor device 100, the heat generated by the semiconductor chip 10 is difficult to transfer to the heat conduction component 40 and the heat dissipation component 50, and tends to accumulate in the sealing resin 30. If heat accumulates in the sealing resin 30, it adversely affects the lifespan of the semiconductor chip 10 and reduces reliability. Furthermore, in achieving increased capacitance and miniaturization of the semiconductor device 100, it is difficult to avoid increasing the heat generated by the semiconductor chip 10. Therefore, a structure that improves the heat dissipation of the heat generated by the semiconductor chip 10 is needed.

[0037] <2. Implementation of Semiconductor Devices>

[0038] [Semiconductor device arrangement]

[0039] Next, the structure of the semiconductor device of this embodiment will be described. Figure 2 as well as Figure 3 This describes the configuration of the semiconductor device in this embodiment. Figure 2 This is a side view showing the mounting structure of the semiconductor device 200 with its packaged structure. Figure 3 yes Figure 2 An enlarged view of the semiconductor chip 10 and the periphery of the heat conduction component 40 of the semiconductor device 200 shown.

[0040] Figure 2 The semiconductor device 200 shown includes a semiconductor chip 10, a substrate 20, a sealing resin 30, a heat-conducting component 40, and a heat-dissipating component 50. The semiconductor chip 10 is mounted on the surface of the substrate 20. The sealing resin 30 is formed in a shape that covers the semiconductor chip 10 and the area of ​​the substrate 20 on which the semiconductor chip 10 is mounted.

[0041] In addition, the semiconductor device 200 with the package structure connects the sealing resin 30 to the heat dissipation component 50 through the heat conduction component 40 formed on the entire back side of the sealing resin 30.

[0042] The semiconductor chip 10 is a general semiconductor device, or it may be a power semiconductor chip, etc. The semiconductor chip 10 has external electrodes for mounting on the substrate 20 and is mounted on the first main surface side of the substrate 20.

[0043] The substrate 20 is, for example, a substrate capable of mounting a semiconductor chip 10 or a lead frame. The semiconductor chip 10 is mounted on chip pads of the substrate 20, and external electrodes of the semiconductor chip 10 are connected to wiring constituting the substrate 20. Furthermore, external terminals 21 for external connections of the substrate 20 extend beyond the sealing resin 30. These extended external terminals 21 are not sealed by the sealing resin 30.

[0044] The sealing resin 30 is formed in a shape that covers a portion of the semiconductor chip 10, the substrate 20, and a portion of the heat dissipation component 50. The entire semiconductor chip 10 is covered by the sealing resin 30. The substrate 20 is covered by the sealing resin 30 in such a way that it includes the area where the semiconductor chip 10 is mounted. The heat dissipation component 50 is covered by the sealing resin 30 in such a way that its back side is exposed to the outside.

[0045] The heat dissipation component 50 is a plate-shaped component with high thermal conductivity. For example, the heat dissipation component 50 is made of Cu, Al, etc.

[0046] A heat-conducting component 40 is filled between the sealing resin 30 and the heat dissipation component 50. The sealing resin 30 and the heat dissipation component 50 do not directly contact each other, but are connected through the heat-conducting component 40. The heat-conducting component 40 is made of silicone gel mixed with highly thermally conductive metal powders such as Cu and Al. In addition, the heat-conducting component 40 is not limited to silicone gel mixed with metal powder, as long as it is a liquid or gel-like material with good thermal conductivity and low hygroscopicity.

[0047] Additionally, the semiconductor device 200 has a hole 60 in the sealing resin 30 on the second main surface side of the substrate 20. For example... Figure 3 As shown, the hole 60 extends from the heat dissipation component 50 side to the second main surface of the substrate 20 through the sealing resin 30. Furthermore, a heat conduction component 40 is filled within the hole 60.

[0048] The heat conduction component 40 is continuously formed from the entire surface between the heat dissipation component 50 and the approach surface of the sealing resin 30 into the hole 60. Therefore, the heat dissipation component 50 is connected to the second main surface side of the substrate 20 via the heat conduction component 40 filling the hole 60.

[0049] In the semiconductor device 200, the aperture 60 is filled with a heat-conducting component 40, which has a higher thermal conductivity than the sealing resin 30. This allows heat generated in the semiconductor chip 10 to move directly from the substrate 20 to the heat-conducting component 40 without passing through the sealing resin 30. Furthermore, by moving heat from the heat-conducting component 40 to the heat-dissipating component 50, the heat dissipation of the semiconductor device 200 can be improved.

[0050] in addition, Figure 4 This illustrates the structure of the sealing resin 30 on the back side of the substrate 20 in the semiconductor device 200. Figure 4 The image shows only the sealing resin 30, the hole 60 formed in the sealing resin 30, and the external terminal 21 leading to the outside of the sealing resin 30.

[0051] like Figure 4As shown, the holes 60 are distributed across the entire surface of the sealing resin 30 on the back side of the substrate 20. In the semiconductor device 200, holes 60 with a circular cross-sectional shape in the planar direction of the substrate 20 are formed. Furthermore, in the semiconductor device 200, the holes 60 are evenly and discontinuously arranged on the second main surface of the substrate 20. Therefore, the holes 60 of the semiconductor device 200 disperse stress caused by the curing shrinkage of the sealing resin 30, thus suppressing warping.

[0052] Furthermore, by providing multiple holes 60 on the second main surface of the substrate 20, the total contact area between the substrate 20 and the heat conduction component 40 can be sufficiently ensured. This improves the fit between the substrate 20 and the heat conduction component 40 and the heat dissipation component 50, thereby enhancing the heat dissipation performance of the semiconductor device 200.

[0053] Therefore, the reliability of the semiconductor device 200 is improved through the above structure.

[0054] From a heat dissipation perspective, it is preferable that the total area of ​​the aperture 60 (the cross-sectional area of ​​the substrate 20 in the surface direction) is large. However, if the area of ​​the aperture 60 is large, the difference in the amount of sealing resin 30 between the first and second main surfaces of the substrate 20 becomes larger. In this case, the stress difference of the sealing resin 30 between the first and second main surfaces becomes larger, and the semiconductor device 200 is prone to warping. Therefore, for example, it is preferable that the total area of ​​the aperture 60 is 50% or more and 70% or less relative to the overall contact area between the sealing resin 30 and the heat dissipation member 50.

[0055] In addition, considering the adhesion between the sealing resin 30 and the substrate 20, it is preferable to ensure that the spacing between each hole 60 is 0.5 mm or more.

[0056] The diameter of each hole 60 needs to be adjusted according to the thickness of the sealing resin 30 formed on the back side of the substrate 20. In order to fill the hole 60 with the heat conduction component 40, the greater the thickness of the sealing resin 30, the larger the diameter of the hole 60 needs to be. For example, the diameter of the hole 60 is preferably set to be the same as the thickness of the sealing resin 30 formed on the back side of the substrate 20.

[0057] Considering the size of the semiconductor device 100, the adhesion between the substrate 20 and the sealing resin 30, and heat dissipation, the thickness of the sealing resin 30 formed on the back side of the substrate 20 is preferably about 0.7 to 1.0 mm. Therefore, the diameter of the hole 60 is preferably 0.7 mm or more and 1.0 mm or less.

[0058] The holes 60 are formed by forming a plurality of holes 60 of the aforementioned diameter, such that the ratio of the total area of ​​the holes 60 to the overall ratio of the contact area between the sealing resin 30 and the heat dissipation component 50 is such that the holes 60 are formed.

[0059] In addition, such as Figure 4 As shown, the holes 60 are preferably arranged equally. For example, the area difference between the individual holes 60 is preferably 10% or less. In addition, the difference in spacing between adjacent holes 60 in one direction is preferably 10% or less.

[0060] The semiconductor device 200 is manufactured, for example, as follows.

[0061] First, a semiconductor chip 10 is mounted on the chip pads of the substrate 20. The substrate 20 with the semiconductor chip 10 mounted is placed in a mold. The mold has a pattern of holes 60 formed on its bottom. With the substrate 20 placed on this bottom pattern, an insulating resin, which serves as a sealing resin 30, is allowed to flow into the mold. Then, after the resin has cured, the semiconductor chip 10 and the substrate 20, sealed by the sealing resin 30 having multiple holes 60, are removed from the mold.

[0062] Thus, a semiconductor device 200 is formed, consisting of a semiconductor chip 10, a substrate 20, and a sealing resin 30 with holes 60 formed therein. Furthermore, after this process, a protective film or similar material may be applied to the back side of the sealing resin 30 to protect the holes 60.

[0063] Next, the semiconductor device 200, consisting of a semiconductor chip 10, a substrate 20, and a sealing resin 30 with holes 60, is moved to the place of use. Then, at the place of use, a protective film is peeled off, and a heat-conducting component 40 is coated on the back side of the sealing resin 30. During the coating of the heat-conducting component 40, the holes 60 are filled with the heat-conducting component 40. Then, the coated surface of the heat-conducting component 40 is attached to the heat dissipation component 50.

[0064] Through the above procedures, it is possible to produce Figure 2 The semiconductor device 200 with the structure shown is shown.

[0065] As described above, the semiconductor device 200 is used by users to coat the heat-conducting component 40 and bond it to the heat-dissipating component 50. Therefore, even when the semiconductor device 200 is composed of a semiconductor chip 10, a substrate 20, and a sealing resin 30 with formed holes 60, it still has the aforementioned effects. That is, by dispersing the holes 60 formed in the sealing resin 30 into a plurality of portions, the semiconductor device 200 mitigates the stress difference caused by the curing shrinkage of the sealing resin 30 on both sides of the substrate 20, and suppresses warping of the package structure caused by uneven stress. Furthermore, by dispersing the holes 60 formed in the sealing resin 30 into a plurality of portions, the exposure of the substrate 20 can be minimized, the intrusion of moisture from the outside can be suppressed, and higher reliability can be ensured.

[0066] <3. Modifications of semiconductor devices>

[0067] Next, a variation of the semiconductor device of this embodiment will be described. Figures 5-7 The structure of a modified example of the semiconductor device will be described. Furthermore, in this modified example, only the shape of the hole formed in the sealing resin 30 differs from the semiconductor device of the above-described embodiment. Therefore, in Figures 5-7 In the text, only those related to the above are shown. Figure 4 The structure shown corresponds to the structure of the sealing resin 30 on the back side of the substrate 20 in the semiconductor device 200.

[0068] exist Figure 5 In the semiconductor device 200 shown, the holes 61 are distributed on the back side of the substrate 20 across the entire surface of the sealing resin 30. Figure 5 The hole 61 shown is a groove-shaped hole formed continuously in one direction on the sealing resin 30. A portion of the hole 61 is formed continuously from one end to the other. Therefore, a portion of the hole 61 is exposed from the side of the sealing resin 30. In this way, by setting the hole 61 to a continuous groove shape in one direction, when the heat conduction member 40 is filled, air bubbles inside the heat conduction member 40 are discharged to the outside of the hole 61. If air bubbles remain inside the hole 61 after the heat conduction member 40 is filled, heat transfer from the substrate 20 to the heat dissipation member 50 is hindered. In addition, since air bubbles are mixed in the heat conduction member 40, the adhesion between the sealing resin 30 and the heat dissipation member 50 is reduced. Therefore, by having Figure 5 The groove-shaped opening 61 shown improves the seal between the sealing resin 30 and the heat dissipation component 50, further enhancing heat dissipation. As a result, the reliability of the semiconductor device 200 is improved.

[0069] Hole 61 is preferably of the width described above. Figure 4 The diameter of the holes 60 shown is the same as that of the holes 60. Furthermore, the ratio of the total area of ​​the holes 61 to the total contact area between the sealing resin 30 and the heat dissipation component 50 can also be set to be the same as that of the holes 61. Figure 4 The same range as the hole 60 shown.

[0070] In addition, such as Figure 6 and Figure 7 As shown, the semiconductor device 200 may also have a structure in which holes 62 and 63 are provided in a portion of the back side of the substrate 20. The semiconductor device 200 dissipates the heat generated by the semiconductor chip 10 mounted on the substrate 20 to the outside through the heat dissipation member 50. Therefore, in the portion of the substrate 20 where the semiconductor chip 10 is mounted, a structure that improves heat dissipation is required. Therefore, in the semiconductor device 200, at least the aforementioned holes 62 and 63 and the heat conduction member 40 need to be arranged at the location where the semiconductor chip 10 is mounted.

[0071] Therefore, the semiconductor device 200 has holes 62 and 63 in the sealing resin 30 at least on the back side of the substrate 20 in the area where the semiconductor chip 10 is mounted, or on the back side of the substrate 20 in the area where the chip pads of the semiconductor chip 10 are mounted. Figure 6 The semiconductor device 200 shown has circular holes 62 formed discontinuously and uniformly in the sealing resin 30 on the back side of the substrate 20 in the region where the semiconductor chip 10 is mounted. Additionally, Figure 7 The semiconductor device 200 shown has groove-shaped holes 63 continuously formed in one direction in the sealing resin 30 on the back side of the substrate 20 in the area where the semiconductor chip 10 is mounted.

[0072] In the semiconductor device 200, the size of each hole 62, 63 is preferably set to the range described above, in the structure where holes 62, 63 are only formed on the back side of the area where the semiconductor chip 10 and chip pads are formed.

[0073] Furthermore, the total area of ​​the holes 62 and 63 is preferably set to the range described above relative to the area where the semiconductor chip 10 or chip pad is formed.

[0074] In a structure where the aperture 60 is provided only in the region of the semiconductor chip 10, the exposure of the substrate 20 can be minimized. Therefore, the semiconductor device 200 with the above structure can suppress the intrusion of moisture from the outside, ensuring higher reliability. Moreover, since the aperture 60 is formed in the region of the semiconductor chip 10, heat dissipation can also be ensured.

[0075] Furthermore, in the above embodiments, the shape of the hole is set to be circular or straight, but the shape of the hole is not particularly limited. For example, the hole can also be a polygon other than a circle, a geometric pattern, or a curved shape other than a straight line.

[0076] Furthermore, the present invention is not limited to the embodiments described above, and various modifications are possible. For example, the embodiments described above are detailed for the purpose of easily understanding and illustrating the present invention, and the present invention is not necessarily limited to having all the structures described. Additionally, a portion of the structure of a certain embodiment can be replaced with the structure of another embodiment. Furthermore, structures of other embodiments can be added to the structure of a certain embodiment. Moreover, a portion of the structure of each embodiment can be deleted, or other structures can be added or replaced.

[0077] Symbol Explanation

[0078] 10: Semiconductor chip; 20: Substrate; 21: External terminal; 30: Sealing resin; 40: Heat conduction component; 50: Heat dissipation component; 60, 61, 62, 63: Hole; 100, 200: Semiconductor device.

Claims

1. A semiconductor device, characterized by comprising: have: Semiconductor chips; A substrate having the semiconductor chip mounted on its first main surface; and A sealing resin that covers the portion of the substrate on which the semiconductor chip is mounted. On the second main surface side opposite to the mounting surface of the semiconductor chip, the sealing resin has a plurality of holes extending through the second main surface of the substrate.

2. The semiconductor device according to claim 1, wherein have: A heat-conducting component that fills the plurality of said holes.

3. The semiconductor device according to claim 2, wherein have: A heat dissipation component, which is bonded to the substrate and the sealing resin via the heat conduction component.

4. The semiconductor device according to claim 1, characterized in that, The sealing resin has the hole at least on the second main surface side of the substrate in the region where the semiconductor chip is mounted.

5. The semiconductor device according to claim 1, characterized in that, The sealing resin has a hole with a circular cross-sectional shape in the face direction of the substrate.

6. The semiconductor device according to claim 1, characterized in that, The sealing resin has groove-shaped holes that are continuously formed in one direction.

7. The semiconductor device according to claim 6, characterized in that, The hole has a groove-shaped portion that extends from one end of the sealing resin to the other end.

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