Semiconductor devices, power conversion devices, mobile bodies, and methods for manufacturing semiconductor devices

Abstract

The object is to provide a technology capable of suppressing positional deviation of electronic components and solder balls even without using a fixture. A semiconductor device comprises an insulating substrate, an electronic component and solder. A metal pattern and a semiconductor element are arranged on the insulating substrate. The metal pattern comprises a first recess and a second recess, and the second recess is arranged in parallel with the first recess. A part of the electronic component is arranged in the first recess. The solder connects the metal pattern arranged on the insulating substrate and the electronic component.

Description

Technical Field

[0001] The present invention relates to a semiconductor device, a power conversion device, a mobile object, and a method for manufacturing a semiconductor device. Background Art

[0002] In the manufacturing process of semiconductor devices, sometimes, after the electronic component is aligned with the metal pattern provided on the insulating substrate, the electronic component is electrically connected to the metal pattern. However, before the metal pattern and the electronic component are connected, the electronic component may move in the plane direction of the insulating substrate due to the transportation of the insulating substrate, causing the position of the electronic component to shift. In this case, there is a problem that the electronic component must be aligned again.

[0003] In order to solve this problem, Reference Document 1 proposes a technology for restricting the movement of electronic components by using a thick side wall of a metal pattern.

[0004] Comparative Document 1: Japanese Patent Application Laid-Open No. 11-345969 Summary of the invention

[0005] In recent years, it has been proposed to use solder balls, the amount of which can be easily managed, as a joining component for electrically connecting a metal pattern and an electronic component. However, since a spherical solder ball is easy to rotate, if a solder ball is used in a structure of the prior art, the position of the solder ball may be shifted before the solder ball melts. Therefore, there is a problem that a jig is required to suppress the position shift of the solder ball.

[0006] Therefore, the present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a technology capable of suppressing positional deviation of electronic components and solder balls without using a jig.

[0007] The semiconductor device involved in the present invention comprises: an insulating substrate, which is provided with a metal pattern and a semiconductor element, the metal pattern having a first recess and a second recess arranged in parallel with the first recess; an electronic component, a part of which is arranged in the first recess; and solder, which connects the metal pattern and the electronic component.

[0008] Effects of the Invention

[0009] According to the present invention, since the metal pattern has the first recess and the second recess, it is possible to suppress positional deviation of the electronic component and the solder ball even without using a jig.

[0010] The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1It is a top view for explaining the manufacturing process of the related semiconductor device.

[0012] Figure 2 It is a cross-sectional perspective view used to explain the manufacturing process of the related semiconductor device.

[0013] Figure 3 It is a cross-sectional perspective view used to explain the manufacturing process of the related semiconductor device.

[0014] Figure 4 It is a cross-sectional view for explaining the manufacturing process of the related semiconductor device.

[0015] Figure 5 It is a cross-sectional perspective view for explaining the manufacturing process of the semiconductor device involved in the first embodiment.

[0016] Figure 6 It is a cross-sectional perspective view for explaining the manufacturing process of the semiconductor device involved in the first embodiment.

[0017] Figure 7 It is a cross-sectional view for explaining the manufacturing process of the semiconductor device involved in Embodiment 1.

[0018] Figure 8 This is a cross-sectional view showing the structure of the semiconductor device according to the first embodiment.

[0019] Fig. 9 This is a block diagram showing a power conversion device according to the second embodiment.

[0020] Fig.10 This is a block diagram showing the structure of a moving object according to the third embodiment. DETAILED DESCRIPTION

[0021] The following is a reference Figure 1 The embodiments are described in detail below. The features described in the following embodiments are examples, and not all features are required. In addition, in the description shown below, the same structural elements are marked with the same or similar numbers in multiple embodiments, and different structural elements are mainly described. In addition, in the description recorded below, specific positions and directions such as "up", "down", "left", "right", "front" and "back" are not necessarily consistent with the directions in actual implementation.

[0022] <Related semiconductor devices>

[0023] First, before describing the semiconductor device according to the first embodiment, a manufacturing process of a semiconductor device related thereto (hereinafter referred to as a "related semiconductor device") will be described. The related semiconductor device is, for example, a power semiconductor device.

[0024] Figure 1It is a top view for explaining a positioning step in the manufacturing process of the related semiconductor device. Figure 2 Before the positioning process Figure 1 A sectional oblique view of the dotted box A portion.

[0025] Before performing the positioning process of the semiconductor device, a semiconductor device having the following Figure 2 The insulating substrate 1 is shown with a metal pattern 2. The metal pattern 2 has two separated parts, and two solder resist layers 3 are respectively disposed on the two parts. The solder resist layer 3 has a "コ" shape in which openings face each other as a plan view shape.

[0026] Here, the upper portion of the metal pattern 2 is substantially flat, and the solder ball used as the bonding member of the metal pattern 2 is spherical. Therefore, even if the solder ball is placed on the designed portion of the metal pattern 2 where the solder ball should be melted, if the insulating substrate 1 is transported to a reflow device for melting the solder ball, the position of the solder ball may be shifted from the designed portion.

[0027] Therefore, in the positioning process of the related semiconductor device, Figure 1 After the insulating substrate 1 and the first jig 51 for positioning the insulating substrate 1 are sequentially placed on a base plate 8 such as a heat sink, the second jig 52 is inserted into the hole of the first jig 51. Thereafter, the semiconductor chip 4 as a semiconductor element, the electronic component 5, and the spherical solder ball are inserted into the hole of the second jig 52.

[0028] Figure 3 After the above embedding Figure 1 The cross-sectional oblique view of the dotted frame A part, Figure 4 yes Figure 3 In addition, Figure 4 , a metal pattern 7 and a bonding member 9 are shown. The metal pattern 7 is disposed on the surface of the insulating substrate 1 opposite to the surface on which the metal pattern 2 is disposed. The bonding member 9 is, for example, solder, and is disposed between the metal pattern 7 and the base plate 8.

[0029] like Figure 3 As shown, both ends of the electronic component 5 are placed in the "コ" shape of the two solder resist layers 3 in the metal pattern 2. Figure 3 as well as Figure 4 As shown, two solder balls 6 a are placed on portions of the metal pattern 2 located near both ends of the electronic component 5 .

[0030] In addition, if Figure 3 as well as Figure 4As shown, the second jig 52 is present around the electronic component 5 and the solder ball 6 a. Therefore, the cylindrical electronic component 5 and the spherical solder ball 6 a are restricted from moving in the in-plane direction of the insulating substrate 1 by the second jig 52 .

[0031] In the manufacturing process of the semiconductor device, after the positioning process, the insulating substrate 1 is transferred to a reflow device and the solder balls 6a are melted. Thus, solder balls 6a are used to form solder that electrically connects the two ends of the electronic component 5 to the two portions of the metal pattern 2. As a result, the two portions of the metal pattern 2 are electrically connected via the electronic component 5.

[0032] Although not shown, the semiconductor chip 4 is also electrically connected to the metal pattern 2 and the like by a bonding member such as solder during the reflow process. Thereafter, the first jig 51 and the second jig 52 are removed from the insulating substrate 1 .

[0033] According to the manufacturing process of the semiconductor device described above, the positional deviation of the electronic component 5 and the solder ball 6a can be suppressed to a certain extent. However, in the manufacturing process of the semiconductor device, there is a problem that a dedicated second jig 52 is required. In addition, there is a problem that the positional deviation of the electronic component 5 and the solder ball 6a occurs according to the amount of the gap between the second jig 52, the first jig 51 and the insulating substrate 1. In contrast, the above-mentioned problems can be solved in the embodiment of the present invention described below.

[0034] <Implementation Method 1>

[0035] Figure 5 as well as Figure 6 is a perspective cross-sectional view for explaining the manufacturing process of the semiconductor device according to the first embodiment. Figure 7 yes Figure 6 In addition, Figure 5 to Figure 7 Corresponding to Figure 2 to Figure 4 Hereinafter, among the components according to the first embodiment, the components that are the same as or similar to the above-described components are denoted by the same or similar reference numerals, and the different components will be mainly described.

[0036] Before the positioning process of the semiconductor device according to the first embodiment, the following preparation is performed: Figure 5 The insulating substrate 1 shown in the figure has a metal pattern 2 having a first recess 2a and a second recess 2b disposed thereon. The first recess 2a is formed at a designed position of the electronic component 5 by, for example, etching the metal pattern 2. The second recess 2b is formed at a designed position of the solder ball 6a by, for example, etching the metal pattern 2, and is arranged in parallel with the first recess 2a.

[0037] like Figure 7 As shown, in the first embodiment, the inner walls of the first recess 2a and the second recess 2b are inclined, and the first recess 2a and the second recess 2b have cross-sectional shapes that widen toward the opening of the first recess 2a and the opening of the second recess 2b, respectively. Figure 5 As shown, in the first embodiment, the first recess 2a and the second recess 2b are separated.

[0038] In addition, Figure 5 In the example, the opening shape of the first recess 2a when viewed from above is a "コ" shape, but is not limited to this. Figure 5 In the example, the opening shape of the second recess 2b when viewed from above is a quadrilateral, but is not limited to this, and may be, for example, a circular shape.

[0039] The solder resist layer 3 is disposed on the metal pattern 2 and has a plan view shape surrounding the first recess 2a and the second recess 2b. Figure 5 In the example shown in FIG. 1 , the solder resist layer 3 has a U-shaped shape surrounding the first recess 2 a and the second recess 2 b as a plan view shape, but the present invention is not limited thereto.

[0040] like Figure 6 as well as Figure 7 As shown, a portion of the electronic component 5 is embedded in the first recess 2a, and a portion of the solder ball 6a is embedded in the second recess 2b. Thus, the positional displacement of the cylindrical electronic component 5 is suppressed by the inner wall of the first recess 2a, and the positional displacement of the spherical solder ball 6a is suppressed by the inner wall of the second recess 2b.

[0041] Thereafter, the insulating substrate 1 is conveyed to a reflow device, and a reflow process is performed to melt the solder balls 6a. The melting forms solder that connects the metal pattern 2 and the electronic component 5.

[0042] Before, after or during the positioning step and the reflow step described above, the semiconductor chip 4 is disposed on the insulating substrate 1. For example, the semiconductor chip 4 is electrically connected to the metal pattern 2 and the electronic component 5 by a bonding member such as solder.

[0043] Figure 8 is a cross-sectional view showing the semiconductor device after the reflow process of the first embodiment, and Figure 7 As mentioned above, Figure 8 The semiconductor device has an insulating substrate 1 and an electronic component 5, wherein a metal pattern 2 is disposed on the insulating substrate 1, the metal pattern 2 has a first recess 2a and a second recess 2b, and a part of the electronic component 5 is disposed in the first recess 2a. Then, Figure 8 The semiconductor device has solder 6 formed by melting solder balls 6a.

[0044] The solder 6 electrically connects the two ends of the electronic component 5 and the two portions of the metal pattern 2. In the first embodiment, a portion of the solder 6 is disposed in the second recess 2b. According to this structure, the contact area between the solder 6 and the metal pattern 2 can be increased, so that the solder 6 can be prevented from peeling off from the metal pattern 2, and the reliability of the semiconductor device can be improved.

[0045] In addition, as described above, in the first embodiment, the first recess 2a and the second recess 2b have a cross-sectional shape that widens toward the opening of the first recess 2a and the opening of the second recess 2b, respectively. According to this structure, the positional deviation and inclination of the electronic component 5 and the solder ball 6a before the reflow process can be suppressed, so that the bonding property of the solder 6 can be improved. In addition, the inner wall of the second recess 2b is inclined, so that the molten solder can easily flow into the electronic component 5 along the inner wall. As a result, the bonding property of the solder 6 can be improved, so the reliability of the semiconductor device can be improved.

[0046] In addition, in the first embodiment, the solder resist layer 3 has a plan view shape surrounding the first recess 2a and the second recess 2b as described above. According to this structure, the wetting extension area of ​​the molten solder can be limited, so the solder can easily flow into the electronic component 5. Thus, the fillet shape and thickness can be ensured, so the bonding property of the solder 6 can be improved, and the reliability of the semiconductor device can be improved.

[0047] Here, when the first recess 2a and the second recess 2b are not separated, the molten solder may flow from the second recess 2b through the first recess 2a to the space below the electronic component 5. In this case, the two separated parts of the metal pattern 2 may be connected by the solder, resulting in a short circuit. In contrast, in the first embodiment, the first recess 2a and the second recess 2b are separated as described above, so that the above-mentioned short circuit can be suppressed.

[0048] <Implementation Method 2>

[0049] The power conversion device according to the second embodiment has a main conversion circuit, and the main conversion circuit has the power conversion device according to the first embodiment. The semiconductor device described above is not limited to a specific power conversion device, but the case where the semiconductor device according to the first embodiment is applied to a three-phase inverter is described as the second embodiment below.

[0050] Fig. 9 1 is a block diagram showing a configuration of a power conversion system to which the power conversion device according to the second embodiment is applied.

[0051] Fig. 9The power conversion system shown is composed of a power supply 100, a power conversion device 200, and a load 300. The power supply 100 is a DC power supply, and supplies DC power to the power conversion device 200. The power supply 100 can be composed of various power supplies, for example, it can be composed of a DC system, a solar cell, a storage battery, or it can be composed of a rectifier circuit connected to an AC system, and an AC / DC converter. In addition, the power supply 100 can also be composed of a DC / DC converter that converts the DC power output from the DC system into a specified power.

[0052] The power conversion device 200 is a three-phase inverter connected between the power source 100 and the load 300, converts the DC power supplied from the power source 100 into AC power, and supplies the AC power to the load 300. Fig. 9 As shown, the power conversion device 200 includes: a main conversion circuit 201, which converts DC power into AC power and outputs it; a drive circuit 202, which outputs a drive signal for driving each switching element of the main conversion circuit 201; and a control circuit 203, which outputs a control signal for controlling the drive circuit 202 to the drive circuit 202.

[0053] Load 300 is a three-phase motor driven by AC power supplied from power converter 200. Load 300 is not limited to a specific use, and is a motor mounted on various electrical devices, such as a motor for hybrid vehicles, electric vehicles, railway vehicles, elevators, or air conditioners.

[0054] The following describes the details of the power conversion device 200. The main conversion circuit 201 has a switching element and a freewheeling diode (not shown), and converts the DC power supplied from the power supply 100 into AC power and supplies it to the load 300 by turning the switching element on and off. There are various structures for the specific circuit structure of the main conversion circuit 201. The main conversion circuit 201 involved in this embodiment 2 is a two-level three-phase full-bridge circuit, which can be composed of six switching elements and six freewheeling diodes connected in reverse parallel to each switching element. Each switching element of the main conversion circuit 201 is composed of the semiconductor device involved in the above-mentioned embodiment 1. The six switching elements are connected in series two by two to form an upper and lower bridge arm, and each upper and lower bridge arm constitutes each phase (U phase, V phase, W phase) of the full-bridge circuit. Moreover, the output terminal of each upper and lower bridge arm, that is, the three output terminals of the main conversion circuit 201, is connected to the load 300.

[0055] The drive circuit 202 generates a drive signal for driving the switch element of the main conversion circuit 201, and supplies it to the control electrode of the switch element of the main conversion circuit 201. Specifically, the drive circuit 202 outputs a drive signal for turning on the switch element and a drive signal for turning off the switch element to the control electrode of each switch element according to a control signal from a control circuit 203 described later. When the switch element is maintained in the on state, the drive signal is a voltage signal (on signal) greater than or equal to the threshold voltage of the switch element, and when the switch element is maintained in the off state, the drive signal is a voltage signal (off signal) less than or equal to the threshold voltage of the switch element.

[0056] The control circuit 203 controls the switching elements of the main conversion circuit 201 to supply the desired power to the load 300. Specifically, the control circuit 203 calculates the time (on time) when each switching element of the main conversion circuit 201 should be turned on based on the power to be supplied to the load 300. For example, the control circuit 203 can control the main conversion circuit 201 by PWM (Pulse Width Modulation) control that modulates the on time of the switching element according to the voltage to be output. In addition, the control circuit 203 outputs a control instruction (control signal) to the drive circuit 202 so that an on signal is output to the switching element that should be turned on and an off signal is output to the switching element that should be turned off at each moment. The drive circuit 202 outputs an on signal or an off signal as a drive signal to the control electrode of each switching element according to the control signal.

[0057] In the power conversion device according to the second embodiment as described above, the semiconductor device according to the first embodiment is used as a switching element of the main conversion circuit 201 , so that a power conversion device with improved reliability can be realized.

[0058] In the second embodiment described above, an example of applying the semiconductor device involved in the first embodiment to a two-level three-phase inverter is described, but the second embodiment is not limited to this and can be applied to various power conversion devices. In the second embodiment, the semiconductor device involved in the first embodiment is a two-level power conversion device, but it can also be a three-level or multi-level power conversion device. When power is supplied to a single-phase load, the above-mentioned semiconductor device can also be applied to a single-phase inverter. In addition, when power is supplied to a DC load, etc., the above-mentioned semiconductor device can also be applied to a DC / DC converter or an AC / DC converter.

[0059] In addition, the power conversion device involved in this embodiment 2 is not limited to the case where the above-mentioned load is an electric motor, and can be used as a power supply device for, for example, an electric discharge machine, a laser processing machine, an induction heating cooker, or a contactless power supply system, and can also be used as a power conditioner for a solar power generation system, a power storage system, etc.

[0060] <Implementation Method 3>

[0061] Fig.10 : is a diagram showing the structure of a moving object according to the third embodiment. Fig.10 The mobile body 400 shown is equipped with the power conversion device 200 according to the second embodiment, and the mobile body 400 can move using the output from the power conversion device 200. According to the above structure, the reliability of the mobile body 400 can be improved. In addition, although the mobile body 400 is described as a railway vehicle, it is not limited to this, and it can also be a hybrid car, an electric car, an elevator, etc.

[0062] In addition, each embodiment can be freely combined, and each embodiment can be appropriately modified or omitted.

[0063] The above description is intended to be illustrative in all aspects and not restrictive, and it should be understood that numerous modifications not shown here are conceivable.

[0064] Description of the label

[0065] 1 insulating substrate, 2 metal pattern, 2a first recess, 2b second recess, 3 solder resist layer, 4 semiconductor chip, 5 electronic component, 6 solder, 6a solder ball.

Claims

1. A semiconductor device comprising: An insulating substrate provided with a metal pattern and a semiconductor element, wherein the metal pattern has a first recess and a second recess arranged in parallel with the first recess; an electronic component, a portion of which is disposed in the first recess; as well as solder connecting the metal pattern and the electronic component, The first recess and the second recess are separated, The first recess and the second recess have cross-sectional shapes that become wider toward the opening of the first recess and the opening of the second recess, respectively. A portion of the solder is disposed in the second recess.

2. The semiconductor device according to claim 1, wherein A solder resist layer is further provided. The solder resist layer is disposed on the metal pattern and has a plan view shape surrounding the first recess and the second recess.

3. A power conversion device, comprising: A main conversion circuit, comprising the semiconductor device according to claim 1 or 2, wherein the main conversion circuit converts input power and outputs the converted power; a driving circuit that outputs a driving signal for driving the semiconductor device to the semiconductor device; as well as A control circuit outputs a control signal for controlling the drive circuit to the drive circuit.

4. A mobile object comprising the power conversion device according to claim 3.

5. A method for manufacturing a semiconductor device, wherein: An insulating substrate provided with a metal pattern is prepared, wherein the metal pattern has a first recess and a second recess separated from the first recess and arranged in parallel with the first recess, embedding a portion of the electronic component into the first recess, embedding a portion of the solder ball into the second recess, By melting the solder balls, solder connecting the metal pattern and the electronic component is formed, The semiconductor element is arranged on the insulating substrate. The first recess and the second recess have cross-sectional shapes that become wider toward the opening of the first recess and the opening of the second recess, respectively. A portion of the solder is disposed in the second recess.

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