Semiconductor device and method of manufacturing the same

Abstract

An object is to provide a technique that can suppress poor fitting between a base plate and a housing in a semiconductor device and can ensure the connectivity of a frame. In the semiconductor device (1), the frames (2, 3) have: first frame portions (2b, 3b) that extend in a direction parallel to the connection surface and are connected to the connection surface; and second frame portions (2a, 3a) that connect the housing (18) and the first frame portions (2b, 3b). The first frame portions (2b, 3b) are divided into a plurality of divided portions (2c, 2d). At least one of the plurality of divided portions (2c, 2d) of the first frame portions (2b, 3b) is an elastic portion that can elastically deform from a first state in which the front end portion is inclined so as to be located below the connection surface to a second state in which it extends in a direction parallel to the connection surface. The divided portion (2d) serving as the elastic portion is connected to the connection surface in a state where it elastically deforms from the first state to the second state.

Description

Technical Field

[0001] The present invention relates to a semiconductor device and a method for manufacturing the semiconductor device. Background Art

[0002] In the case of existing semiconductor devices, in order to reduce stress on the connection portion between an external connection terminal (equivalent to a frame) and a conductive pattern, an interference portion is sometimes provided in the external connection terminal (for example, refer to Patent Document 1).

[0003] In addition, there is a semiconductor device having the following structure (for example, refer to Patent Document 2),

[0004] That is, in a natural state, the front end portion of a metal wiring board (equivalent to a frame) faces downward at an angle greater than a right angle, and the front end portion is pressed against the conductive pattern by elastic deformation to make contact in a conductively connected manner.

[0005] In addition, the size is designed such that the foremost end portion of the main terminal (equivalent to a frame) is located below the upper surface of the conductive pattern in a normal state, and a spring action is applied when welding is performed during assembly. That is, it has the following structure, in which the upper surface of the conductive pattern is crimped with the lower end portion of the main terminal, and the lower end portion of the main terminal makes contact over the entire surface without being inclined (for example, refer to Patent Document 3).

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2017-228630

[0007] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2008-226920

[0008] Patent Document 3: Japanese Unexamined Patent Application Publication No. 11-177017 Summary of the Invention

[0009] In existing semiconductor devices, there is the following problem. That is, when connecting a frame and a semiconductor element or a conductive pattern with solder, since the connection is performed at a high temperature, warping occurs in the base plate due to the difference in the coefficient of thermal expansion between the insulating substrate having the conductive pattern and the base plate, and a gap is generated between the connection surface of the frame and the semiconductor element or the conductive pattern, and the connectivity of the frame cannot be ensured.

[0010] In order to ensure the connectivity of the frame, it is conceivable to extend the length of the frame in consideration of the warping of the base plate at high temperature and reduce the gap between the frame and the connection surface. However, even if the connectivity of the frame can be ensured, since the rigidity of the frame is high, the housing is pulled by one end portion of the frame provided in the housing, and there is a problem that poor fitting between the base plate and the housing may occur.

[0011] Accordingly, an object of the present invention is to provide a technique in a semiconductor device that can suppress poor fitting between a base plate and a housing and can ensure the connectivity of a frame.

[0012] The semiconductor device according to the present invention includes: a base plate; an insulating substrate that is fixed on the base plate and has a conductive pattern on an upper surface thereof; a semiconductor element that is mounted on the conductive pattern; a housing that is fixed to the base plate and surrounds the insulating substrate and the semiconductor element; and a frame, one end of which is provided on the housing and the other end of which is connected to a connection surface of the conductive pattern or the semiconductor element. The frame includes: a first frame portion that extends in a direction parallel to the connection surface and is connected to the connection surface; and a second frame portion that connects the housing and the first frame portion. The first frame portion is divided into a plurality of divided portions, and at least one of the plurality of divided portions of the first frame portion is an elastic portion that can be elastically deformed from a first state in which a front end portion is located below the connection surface to a second state that extends in a direction parallel to the connection surface, and the elastic portion is connected to the connection surface in a state of being elastically deformed from the first state to the second state.

[0013] Effects of the Invention

[0014] According to the present invention, in a state where the elastic portion of the frame is elastically deformed from the first state to the second state, since it is connected to the connection surface, when warping occurs in the base plate at high temperature, the elastic portion attempts to return from the second state to the first state by its own restoring force, and thus the elastic portion follows the warping of the base plate. Thereby, the connectivity of the frame can be ensured.

[0015] Moreover, since the first frame portion is divided into a plurality of divided portions, the rigidity of the first frame portion is reduced, and thus it is possible to suppress the housing from being pulled by one end portion of the frame. Thereby, poor fitting between the base plate and the housing can be suppressed.

[0016] The object, features, solutions, and advantages of the present invention will become clearer through the following detailed description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a cross-sectional view showing an example of the semiconductor device according to Embodiment 1.

[0018] Figure 2 is a cross-sectional view showing another example of the semiconductor device according to Embodiment 1.

[0019] Figure 3 is a cross-sectional view showing still another example of the semiconductor device according to Embodiment 1.

[0020] Figure 4 A side view of the first frame portion of the frame and its peripheral portion of the semiconductor device according to Embodiment 1.

[0021] Figure 5 An axonometric view of the first frame portion of the frame and its peripheral portion of the semiconductor device according to Embodiment 1.

[0022] Figure 6 An axonometric view of the first frame portion of the frame and its peripheral portion of the semiconductor device according to Embodiment 2.

[0023] Figure 7 A cross-sectional view of the housing and the frame of the semiconductor device according to Embodiment 3.

[0024] Figure 8 An axonometric view of the first frame portion of the frame and its peripheral portion of the semiconductor device according to Embodiment 4.

[0025] Figure 9 A front view of the dividing portion and the slit of the frame of the semiconductor device according to Embodiment 4. Detailed implementation manners

[0026] <Embodiment 1>

[0027] Embodiment 1 will be described below with reference to the accompanying drawings. Figure 1 A cross-sectional view showing an example of the semiconductor device 1 according to Embodiment 1. Figure 2 A cross-sectional view showing another example of the semiconductor device 1 according to Embodiment 1. Figure 3 A cross-sectional view showing another example of the semiconductor device 1 according to Embodiment 1.

[0028] As Figure 1 shown, the semiconductor device 1 includes a base plate 19, an insulating substrate 16, a semiconductor element 12, a housing 18, and frames 2 and 3.

[0029] The base plate 19 is formed of a metal such as copper, and is formed in a rectangular shape when viewed from above. The insulating substrate 16 is formed of, for example, epoxy resin, and is fixed to the upper surface of the base plate 19 via a solder 17. The insulating substrate 16 has a conductive pattern 15 formed of copper on the upper surface, for example.

[0030] The semiconductor element 12 is mounted on the upper surface of the conductive pattern 15 via the solder 13. The housing 18 is formed in a rectangular frame shape in a plan view and is fitted to the peripheral portion of the upper surface of the base plate 19. Further, the base plate 19 surrounds the insulating substrate 16 and the semiconductor element 12. Inside the housing 18, for example, a potting resin (not shown) made of a thermosetting resin is filled, and the potting resin encapsulates the inside of the housing 18.

[0031] The frames 2 and 3 are formed of, for example, thin copper plates. One end of the frame 2 is provided on the upper part of the housing 18, and the other end is connected via the solder 14 with the upper surface of the conductive pattern 15 as a connection surface. One end of the frame 3 is provided on the upper part of the housing 18, and the other end is connected via the solder 11 with the electrode of the semiconductor element 12 as a connection surface.

[0032] Specifically, the frame 2 has a first frame portion 2b and a second frame portion 2a. The first frame portion 2b includes the other end of the frame 2. The first frame portion 2b extends in a direction parallel to the connection surface, i.e., the upper surface of the conductive pattern 15, and is connected to the connection surface. The second frame portion 2a includes one end of the frame 2 and connects the housing 18 and the first frame portion 2b. Further, in a cross-sectional view, the horizontal portion extending in the left-right direction and the vertical portion extending downward from the other end of the horizontal portion in the second frame portion 2a are formed in an L shape. Figure 1 In the [description], the horizontal portion extending in the left-right direction and the vertical portion extending downward from the other end of the horizontal portion are formed in an L shape.

[0033] The frame 3 has a first frame portion 3b and a second frame portion 3a. The first frame portion 3b includes the other end of the frame 3. The first frame portion 3b extends in a direction parallel to the connection surface, i.e., the electrode of the semiconductor element 12, and is connected to the connection surface. The second frame portion 3a includes one end of the frame 3 and connects the housing 18 and the first frame portion 3b. Further, in a cross-sectional view, the horizontal portion extending in the left-right direction and the vertical portion extending downward from the other end of the horizontal portion in the second frame portion 3a are formed in an L shape. Figure 1 In the [description], the horizontal portion extending in the left-right direction and the vertical portion extending downward from the other end of the horizontal portion are formed in an L shape.

[0034] Further, as Figure 2 shown, the conductive pattern 15 may be divided into two, and in this case, the two conductive patterns 15 may also be connected by the wire 20. Or, as Figure 3 shown, the two conductive patterns 15 may also be connected via the solder 22 by the frame 21.

[0035] Next, [tools] Figure 4 and Figure 5 are used to describe the first frame portion 2b of the frame 2 in detail. Figure 4 is a side view of the first frame portion 2b of the frame 2 included in the semiconductor device 1 according to Embodiment 1 and its peripheral portion. Figure 5It is a perspective view of the first frame portion 2b of the frame 2 and its peripheral portion included in the semiconductor device 1 according to Embodiment 1. In addition, since the first frame portion 3b of the frame 3 has the same structure as the first frame portion 2b of the frame 2, description thereof is omitted. The same applies to Embodiments 2 to 4.

[0036] As Figure 4 and Figure 5 shown, the first frame portion 2b is divided into two divided portions 2c and 2d. The divided portion 2c extends in a direction parallel to the connection surface. The divided portion 2d is an elastic portion that can be elastically deformed from a first state ( Figure 4 and Figure 5 the state shown) in which the front end portion is located below the connection surface to a second state ( Figure 1 the state shown) extending in a direction parallel to the connection surface.

[0037] Next, connection of the first frame portion 2b to the connection surface will be described. First, the frame 2 having the divided portion 2d in the first state is prepared. Next, the divided portion 2c is connected to the connection surface using solder 14, and in a state where the divided portion 2d is elastically deformed from the first state to the second state, the divided portion 2d is connected to the connection surface using solder 14, whereby the first frame portion 2b is connected to the connection surface.

[0038] When the frame 2 and the conductive pattern 15 are connected by the solder 14, since the connection is performed at a high temperature, warpage occurs in the base plate 19 due to the difference in the thermal expansion coefficients of the insulating substrate 16 and the base plate 19. At this time, the divided portion 2d attempts to return from the second state to the first state by its own restoring force, and thus the divided portion 2d follows the warpage of the base plate 19 at high temperature.

[0039] In addition, a slit 4 is formed between the adjacent divided portions 2c and 2d of the first frame portion 2b. The slit 4 is formed from the front end portion to the root end portion of the first frame portion 2b. Since the first frame portion 2b is divided into two by the slit 4, the rigidity of the first frame portion 2b is reduced.

[0040] Here, the first frame portion 2b may also be divided into three or more. In this case, at least one of the plurality of divided portions of the first frame portion 2b may be an elastic portion. By increasing the number of divided portions, the rigidity of the first frame portion 2b can be further reduced.

[0041] As described above, the semiconductor device 1 according to Embodiment 1 includes: a base plate 19; an insulating substrate 16 that is fixed on the base plate 19 and has a conductive pattern 15 on its upper surface; a semiconductor element 12 that is mounted on the conductive pattern 15; a housing 18 that is fixed to the base plate 19 and surrounds the insulating substrate 16 and the semiconductor element 12; and frames 2 and 3, one end of which is provided on the housing 18 and the other end of which is connected to the connection surface of the conductive pattern 15 or the semiconductor element 12. The frames 2 and 3 include: first frame portions 2b and 3b that extend in a direction parallel to the connection surface and are connected to the connection surface; and second frame portions 2a and 3a that connect the housing 18 and the first frame portions 2b and 3b. The first frame portions 2b and 3b are divided into a plurality of divided portions 2c and 2d, and at least one of the plurality of divided portions 2d of the first frame portions 2b and 3b is an elastic portion that can be elastically deformed from a first state in which the front end portion is located below the connection surface to a second state that extends in a direction parallel to the connection surface. The divided portion 2d serving as the elastic portion is connected to the connection surface in a state of being elastically deformed from the first state to the second state.

[0042] In addition, the manufacturing method of the semiconductor device according to Embodiment 1 includes: step (a) of preparing the frames 2 and 3 having an elastic portion in the first state; and step (b) of connecting the first frame portions 2b and 3b to the connection surface in a state where the elastic portion is elastically deformed from the first state to the second state.

[0043] Therefore, since the divided portion 2d serving as the elastic portion of the frames 2 and 3 is connected to the connection surface in a state of being elastically deformed from the first state to the second state, when the base plate 19 warps at a high temperature, the divided portion 2d attempts to return from the second state to the first state by its own restoring force, and thus the divided portion 2d follows the warping of the base plate 19. Thereby, the connectivity of the frames 2 and 3 can be ensured.

[0044] Moreover, since the first frame portions 2b and 3b are divided into a plurality of divided portions 2c and 2d, the rigidity of the first frame portions 2b and 3b is reduced, and thus the pulling of the housing 18 by one end of the frames 2 and 3 can be suppressed. Thereby, the poor fitting between the base plate 19 and the housing 18 can be suppressed. According to the above, the yield of the semiconductor device 1 can be improved.

[0045] In addition, since the solders 14 and 11 climb up to the sides of the portions where the slits 4 are formed in the first frame portions 2b and 3b of the frames 2 and 3, respectively, it is easy to visually confirm the amounts of the solders 14 and 11 between the frame 2 and the conductive pattern 15 and between the frame 3 and the semiconductor element 12.

[0046] <Embodiment 2>

[0047] Next, the semiconductor device 1 according to Embodiment 2 will be described. Figure 6 It is a perspective view of the first frame portion 2b of the frame 2 and its peripheral portion included in the semiconductor device according to Embodiment 2. In addition, in Embodiment 2, the same reference numerals are given to the structural elements that are the same as those described in Embodiment 1, and the description thereof is omitted.

[0048] As Figure 6 shown, in Embodiment 2, the slit 4 is formed from the front end portion of the first frame portion 2b to the peripheral portion of the first frame portion 2b in the second frame portion 2a. Specifically, the slit 4 is formed from the front end portion of the first frame portion 2b to the lower part of the vertical portion in the second frame portion 2a, and the length of the slit 4 is longer than that in the case of Embodiment 1. Thereby, the rigidity of the first frame portion 2b can be further reduced. Here, the slit 4 formed in the frame 3 is also formed long in the same manner as the slit 4 formed in the frame 2.

[0049] As described above, regarding the semiconductor device 1 according to Embodiment 2, the slit 4 is formed between adjacent divided portions in the first frame portions 2b and 3b, and the slit 4 is formed from the front end portions of the first frame portions 2b and 3b to the peripheral portions of the first frame portions 2b and 3b in the second frame portions 2a and 3a.

[0050] Therefore, the rigidity of the first frame portions 2b and 3b can be further reduced, and thus the poor fitting between the base plate 19 and the housing 18 can be further suppressed.

[0051] <Embodiment 3>

[0052] Next, the semiconductor device 1 according to Embodiment 3 will be described. Figure 7 It is a cross-sectional view of the housing 18 and the frame 2 included in the semiconductor device 1 according to Embodiment 3. Here, in Figure 7 order to make the drawing easy to see, the illustration of the divided portion 2c is omitted. In addition, in Embodiment 3, the same reference numerals are given to the structural elements that are the same as those described in Embodiments 1 and 2, and the description thereof is omitted.

[0053] As Figure 7 shown, in Embodiment 3, the cutout 5 is formed in the width direction over the surface of the root end portion in the divided portion 2d of the frame 2. The cutout 5 is formed to be less than or equal to 1 / 3 of the thickness of the frame 2. Thereby, the rigidity of the frame 2 can be further reduced. Here, the cutout 5 is also formed in the first frame portion 3b of the frame 3.

[0054] As described above, regarding the semiconductor device 1 according to Embodiment 3, a cut 5 that is less than or equal to 1 / 3 of the thickness of the frames 2 and 3 is formed on the surface of the root end portion of the dividing portions 2d of the frames 2 and 3. Therefore, the rigidity of the frames 2 and 3 can be further reduced, and thus the poor fitting between the base plate 19 and the housing 18 can be further suppressed.

[0055] <Embodiment 4>

[0056] Next, the semiconductor device 1 according to Embodiment 4 will be described. Figure 8 It is a perspective view of the first frame portion 2b of the frame 2 and its peripheral portion of the semiconductor device 1 according to Embodiment 4. Figure 9 It is a front view of the dividing portions 2c, 2d and the slit 4 of the frame 2 of the semiconductor device 1 according to Embodiment 4. In addition, in Embodiment 4, the same reference numerals are assigned to the structural elements that are the same as those described in Embodiments 1 to 3, and the description thereof is omitted.

[0057] As Figure 8 shown, in Embodiment 4, each of the dividing portions 2c, 2d in the first frame portion 2b of the frame 2 is a trapezoid with an upper base longer than the lower base when viewed from the front. Therefore, as Figure 9 shown, in a state where the dividing portion 2d is elastically deformed into the second state, the slit 4 between the dividing portions 2c, 2d is a trapezoid with an upper base shorter than the lower base when viewed from the front. Thereby, when connecting with the solder 14, the solder 14 easily climbs up to the side surface of the portion of the frame 2 where the slit 4 is formed, and the connectivity of the frame 2 is improved. Here, the shape of the dividing portion in the first frame portion 3b of the frame 3 is also the same as that of the first frame portion 2b of the frame 2.

[0058] As described above, regarding the semiconductor device 1 according to Embodiment 4, each of the dividing portions 2c, 2d in the first frame portions 2b, 3b is a trapezoid with an upper base longer than the lower base when viewed from the front. Therefore, when connecting with the solders 14, 11, the solders 14, 11 easily climb up to the side surfaces of the portions of the frames 2, 3 where the slit 4 is formed. Thereby, the connectivity of the frames 2, 3 can be improved, and it is easy to visually confirm the amounts of the solders 14, 11 between the frame 2 and the conductive pattern 15 and between the frame 3 and the semiconductor element 12.

[0059] Although the present invention has been described in detail, the above invention is merely illustrative in all aspects, and the present invention is not limited thereto. It should be understood that countless variations that are not illustrated can be envisioned without departing from the scope of the present invention.

[0060] In addition, the respective embodiments can be freely combined, and the respective embodiments can be appropriately deformed and omitted.

[0061] Description of reference numerals

[0062] 1 Semiconductor device, 2 Frame, 2a First frame portion, 2b Second frame portion, 2c, 2d Division portions, 3 Frame, 3a First frame portion, 3b Second frame portion, 4 Slit, 5 Notch, 15 Conductive pattern, 16 Insulating substrate, 18 Housing, 19 Base plate.

Claims

1. A semiconductor device, comprising: A base plate; An insulating substrate fixed on the base plate and having a conductive pattern on the upper surface thereof; A semiconductor element mounted on the conductive pattern; A housing fixed to the base plate and surrounding the insulating substrate and the semiconductor element; and A frame, one end of which is provided on the housing and the other end is connected to the connection surface of the conductive pattern or the semiconductor element, The frame has: a first frame portion extending in a direction parallel to the connection surface and connected to the connection surface; And a second frame portion connecting the housing and the first frame portion, The first frame portion is divided into a plurality of divided portions, At least one of the plurality of divided portions of the first frame portion is an elastic portion, which can be elastically deformed from a first state in which the front end portion is inclined in a manner lower than the connection surface to a second state extending in a direction parallel to the connection surface, Only a part of the plurality of divided portions is the elastic portion, and the remaining divided portions extend in a direction parallel to the connection surface, The elastic portion is connected to the connection surface in a state elastically deformed from the first state to the second state.

2. The semiconductor device according to claim 1, wherein A slit is formed between adjacent divided portions of the first frame portion, The slit is formed from the front end portion of the first frame portion to the peripheral portion of the first frame portion in the second frame portion.

3. The semiconductor device according to claim 1 or 2, wherein A cut having a size less than or equal to 1 / 3 of the thickness of the frame is formed on the surface of the root end portion of the elastic portion.

4. The semiconductor device according to claim 1 or 2, wherein Each of the divided portions in the first frame portion is a trapezoid having an upper base longer than a lower base when viewed from the front.

5. A method of manufacturing a semiconductor device, the semiconductor device having: a base plate; an insulating substrate fixed on the base plate and having a conductive pattern on the upper surface thereof; a semiconductor element mounted on the conductive pattern; a housing fixed to the base plate and surrounding the insulating substrate and the semiconductor element; and a frame, one end of which is provided on the housing and the other end is connected to the connection surface of the conductive pattern or the semiconductor element, The frame has: a first frame portion that extends in a direction parallel to the connection surface and is connected to the connection surface; And a second frame portion connecting the housing and the first frame portion, The first frame portion is divided into a plurality of divided portions, At least one of the plurality of divided portions of the first frame portion is an elastic portion, which can be elastically deformed from a first state in which the front end portion is inclined in a manner lower than the connection surface to a second state extending in a direction parallel to the connection surface, Only a part of the plurality of divided portions is the elastic portion, and the remaining divided portions extend in a direction parallel to the connection surface, The method of manufacturing the semiconductor device includes: Step (a), preparing the frame having the elastic portion in the first state; And Step (b), while the elastic portion is elastically deformed from the first state to the second state, connecting the first frame portion to the connection surface.

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