Coating device, and method for manufacturing power semiconductor module and physical quantity sensor

Abstract

To provide a coating device that can reduce entrainment of ambient air from a moving portion of the coating device and reduce air bubbles, a power semiconductor module, and a manufacturing method of a physical quantity sensor.SOLUTION: A coating device 1 includes a dispenser 10 having a liquid agent pumping unit 16 that discharges a fixed amount of a liquid agent 13 and a syringe 14 that stores the liquid agent 13, and a device vacuum chamber 21 in which a device to be coated 12 including a power semiconductor module 44 or a physical quantity sensor 51 is arranged and the interior of which can be maintained in a vacuum. A manufacturing method of a physical quantity sensor includes a first step of placing the device to be coated 12 in the device vacuum chamber 21 and evacuating the device vacuum chamber 21, a second step of applying the liquid agent 13 to the device to be coated 12 after evacuating the device vacuum chamber 21, and a third step of opening the device vacuum chamber 21 to the atmosphere after applying the liquid agent 13 and taking out the device 12 to be coated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a coating apparatus, and a method for manufacturing a power semiconductor module and a physical quantity sensor. [Background technology]

[0002] A power semiconductor module is a power semiconductor device that incorporates one or more power semiconductor chips to form part or all of a conversion connection, and has a structure in which the power semiconductor chips are electrically isolated from the laminated substrate or metal substrate. Power semiconductor modules are used in industrial applications such as motor drive control inverters for elevators, etc. In recent years, they have also become widely used in automotive motor drive control inverters. Automotive inverters must be compact and lightweight to improve fuel efficiency, and because they are placed near the drive motor in the engine compartment, they must be highly reliable even at high temperatures.

[0003] Compared to industrial power semiconductor modules, automotive power semiconductor modules are required to be smaller and lighter due to the constraints of installation space. Furthermore, as the output power density for driving motors increases, the temperature of semiconductor chips during operation rises, and the demand for long-term reliability during high-temperature operation also increases. For this reason, a power semiconductor module structure capable of high-temperature operation and long-term reliability is required.

[0004] In such a power semiconductor module, the top surface of the semiconductor chip is connected to the electrode pattern with a metal wire, and the case of the power semiconductor module is filled with a sealing resin to protect the semiconductor chip and the metal wire. The sealing resin is, for example, an epoxy resin, which is injected into the case in a gel state and then heated to harden.

[0005] Furthermore, numerous physical quantity sensors have traditionally been used in automobiles and industrial equipment. Physical quantity sensors include pressure sensors and acceleration sensors, and are often used in harsh environments with high temperatures and humidity. For physical quantity sensor devices, a technology has been proposed in which a package is constructed from a resin case in which a sense element is placed in a recess, and a socket portion that serves as an interface for transmitting signals from the sense element to the outside. In physical quantity sensors, a sensor chip that measures a physical quantity is placed in a resin case. When the physical quantity sensor is a pressure sensor, the sensor chip is a pressure sensor chip that converts strain generated on its front surface when pressure is applied into a resistance value.

[0006] Even in such physical quantity sensors, the sensor chip is connected to a lead terminal for extracting a signal to the outside with a metal wire, and a gel-like liquid is injected into the resin case to protect the sensor chip and the metal wire.

[0007] When injecting a liquid into a power semiconductor module or a physical quantity sensor, the liquid may be injected under vacuum to prevent bubbles in the liquid, reduce injection variations during injection, and shorten the injection time.For example, a known technology is to apply liquid resin to the workpiece from a resin discharge unit in a vacuum chamber, preventing air bubbles from being trapped at the interface between the liquid resin and the workpiece, resulting in sealing (see Patent Document 1 below).

[0008] Fig. 7 is a cross-sectional view showing a conventional method for manufacturing a power semiconductor module and a physical quantity sensor, and Fig. 8 is a flowchart showing a conventional method for manufacturing a power semiconductor module and a physical quantity sensor.

[0009] 7 and 8 show a process of injecting gel into a power semiconductor module and a physical quantity sensor in a conventional method for manufacturing a power semiconductor module and a physical quantity sensor. Fig. 7 shows an example of an application device 101 equipped with a screw dispenser 110.

[0010] In a conventional liquid injection process, first, the syringe 114 is replaced, the switching valve 120 is opened, and the liquid 113 that has been mixed with air during replacement is discharged (step S101). Next, the application pressure and application time of the application device 101 are set (step S102). Next, the device to be coated 112 is placed in the vacuum chamber 123, and the vacuum chamber 123 is evacuated (step S103), creating a vacuum in the vacuum chamber 123. The device to be coated 112 is a power semiconductor module or a physical quantity sensor.

[0011] Next, after confirming the initial application amount, application is started (step S104). For example, the switching valve 120 is closed, and the application device 101 injects the liquid agent 113 in the syringe 114 into the liquid agent storage section 115 in the screw dispenser 110. Next, the application device 101 rotates the rotation shaft 119 to rotate the screw-type rotor 117, applies pressure to the liquid agent pressure-feeding section 116, and injects the liquid agent 113 from the nozzle 111 into the device to be applied 112. At this time, the nozzle 111 and the device to be applied 112 are placed in a vacuum chamber 123, so that the injection of the liquid agent 113 is carried out under vacuum.

[0012] Next, the vacuum chamber 123 is opened to the atmosphere, and the apparatus 112 to be coated is removed (step S105). This completes the injection of the liquid agent 113 into one apparatus 112 to be coated, and steps S103 to S105 are repeated for each of the apparatuses 112 to be coated. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-2170006 Summary of the Invention [Problem to be solved by the invention]

[0014] However, in the conventional method, the tip of the nozzle 111 and the coated device 112 are placed in a vacuum chamber 123, but the moving parts of the coating device 101, such as a mono pump, a screw pump, and a plunger pump, are set under atmospheric pressure. In the case of the screw dispenser 110 in Figure 7, the liquid pressure-feeding part 116 corresponds to the screw pump.

[0015] For this reason, surrounding air may be drawn in as the coating device 101 moves. In this case, even if the injection environment into the coated device 112 is under vacuum, surrounding air may be drawn in through tiny gaps in the moving parts during operation, and air bubbles may be mixed into the coating device 101. For example, in the case of FIG. 7, air may enter through bearing 118 due to the rotation of rotating shaft 119, causing air bubbles 124 to be mixed into the liquid agent storage section 115. If air bubbles are mixed in, the injection amount may vary, the surrounding area may be contaminated, and product quality may be affected.

[0016] In order to solve the problems of the conventional technology described above, the present invention aims to provide a coating device that can reduce the entrainment of ambient air from the moving parts of the coating device and reduce the inclusion of air bubbles, and a method for manufacturing a power semiconductor module and a physical quantity sensor. [Means for solving the problem]

[0017] In order to solve the above-mentioned problems and achieve the object of the present invention, the coating device according to the present invention has the following features: It includes a dispenser having a liquid pressure-feeding unit that dispenses a fixed amount of liquid and a syringe that stores the liquid, and an apparatus vacuum chamber that can maintain a vacuum inside and that accommodates the dispenser and an apparatus to be coated, the apparatus having a case in which a semiconductor chip is arranged. The dispenser has a screw rotor, a bearing, and a rotating shaft, and rotates the rotating shaft to rotate the screw rotor and apply the liquid agent to the device to be coated.

[0018] In order to solve the above-mentioned problems and achieve the object of the present invention, the coating device according to the present invention has the following features: It comprises a dispenser having a liquid pressure-feeding unit that dispenses a fixed amount of liquid and a syringe that stores the liquid, a vacuum chamber that can hold a vacuum inside and in which a device to be coated having a semiconductor chip disposed in a case is placed, and a movable part vacuum chamber that can hold a vacuum inside and in which a movable part of the dispenser is placed. The dispenser has a screw-type rotor, a bearing, and a rotating shaft, the bearing in contact with the atmosphere and the portion of the rotating shaft protruding from the liquid agent reservoir are provided in the movable part vacuum chamber, By rotating the rotary shaft, the screw rotor is rotated, and the liquid agent is applied to the device to be coated.

[0019] In order to solve the above-mentioned problems and achieve the object of the present invention, the manufacturing method of a power semiconductor module and a physical quantity sensor according to the present invention has the following features. In a coating apparatus including a dispenser having a liquid pressure-feeding unit that dispenses a fixed amount of liquid and a syringe that stores the liquid, and an apparatus vacuum chamber that can maintain a vacuum inside and that accommodates the dispenser and a coated device consisting of a power semiconductor module or a physical quantity sensor, the apparatus vacuum chamber is placed in a first step of evacuating the apparatus vacuum chamber. Next, after evacuating the apparatus vacuum chamber, the liquid is applied to the coated device in a second step. Next, after applying the liquid, the apparatus vacuum chamber is opened to the atmosphere and the coated device is removed in a third step. The dispenser has a screw-type rotor, a bearing, and a rotating shaft, and in the second step, the rotating shaft is rotated to rotate the screw-type rotor and apply the liquid agent to the device to be coated.

[0020] In order to solve the above-mentioned problems and achieve the object of the present invention, the manufacturing method of the power semiconductor module and physical quantity sensor according to the present invention has the following features. In a coating device including a dispenser having a liquid pressure-feeding unit that dispenses a fixed amount of liquid and a syringe that stores the liquid, a vacuum chamber that can hold a vacuum inside and that accommodates a device to be coated, which is a power semiconductor module or a physical quantity sensor, and a movable part vacuum chamber that accommodates a movable part of the dispenser and that can hold a vacuum inside, a first step is performed in which the movable part vacuum chamber is evacuated. Next, a second step is performed in which the device to be coated is placed in the vacuum chamber and the inside of the vacuum chamber is evacuated. Next, after the movable part vacuum chamber and the vacuum chamber are evacuated, a third step is performed in which the liquid is applied to the device to be coated. Next, after the liquid is applied, a fourth step is performed in which the vacuum chamber is opened to the atmosphere and the device to be coated is removed. The dispenser has a screw-type rotor, a bearing, and a rotating shaft, the bearing in contact with the atmosphere and the portion of the rotating shaft protruding from the liquid agent reservoir are provided in the movable part vacuum chamber, In the third step, the rotation shaft is rotated to rotate the screw rotor, thereby applying the liquid agent to the device to be coated.

[0021] Further, a method for manufacturing a power semiconductor module and a physical quantity sensor according to the present invention is provided, in the above-mentioned invention, 1 construction The method further comprises a fifth step of replacing the syringe before the step of replacing the syringe and discharging the liquid agent that has become air-mixed during the replacement from the syringe.

[0022] Furthermore, the manufacturing method of the power semiconductor module and the physical quantity sensor according to the present invention is characterized in that, in the above-described invention, the liquid agent is applied to an area where a semiconductor chip and a metal wire are connected in the power semiconductor module and the physical quantity sensor. [Effects of the Invention]

[0023] The coating device and the method for manufacturing a power semiconductor module and a physical quantity sensor according to the present invention have the effect of reducing the amount of ambient air drawn in from the moving parts of the coating device, thereby reducing the amount of air bubbles mixed in. [Brief explanation of the drawings]

[0024] [Figure 1] 3A to 3C are cross-sectional views illustrating a method for manufacturing the power semiconductor module and the physical quantity sensor according to the first embodiment. [Figure 2] 4 is a flowchart showing a method for manufacturing the power semiconductor module and the physical quantity sensor according to the first embodiment. [Figure 3] 1 is a cross-sectional view showing the structure of a power semiconductor module according to a first embodiment. [Figure 4] 1 is a cross-sectional view showing a structure of a physical quantity sensor according to a first embodiment. [Figure 5] 10A to 10C are cross-sectional views illustrating a method for manufacturing a power semiconductor module and a physical quantity sensor according to a second embodiment. [Figure 6] 10 is a flowchart showing a method for manufacturing the power semiconductor module and the physical quantity sensor according to the second embodiment. [Figure 7] 10A and 10B are cross-sectional views showing a conventional method for manufacturing a power semiconductor module and a physical quantity sensor. [Figure 8] 10 is a flowchart showing a conventional method for manufacturing a power semiconductor module and a physical quantity sensor. DETAILED DESCRIPTION OF THE INVENTION

[0025] Preferred embodiments of the coating device and the method for manufacturing a power semiconductor module and a physical quantity sensor according to the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described below.

[0026] (Embodiment 1) Fig. 1 is a cross-sectional view showing a method for manufacturing a power semiconductor module and a physical quantity sensor according to the first embodiment. Fig. 2 is a flowchart showing a method for manufacturing a power semiconductor module and a physical quantity sensor according to the first embodiment. Figs. 1 and 2 show a step of injecting gel into the power semiconductor module and the physical quantity sensor in the method for manufacturing a power semiconductor module and a physical quantity sensor according to the first embodiment. Other steps in the method for manufacturing a power semiconductor module and a physical quantity sensor are similar to steps that have been generally performed in the past, and therefore description thereof will be omitted.

[0027] Here, the coating device 1 is composed of a dispenser that dispenses a fixed amount of liquid 13 and a syringe 14 that stores the liquid 13, and is a device that applies the liquid 13 to a device to be coated 12. FIG. 1 shows an example of the coating device 1 that includes a screw dispenser 10 as the dispenser. A dispenser is a device that dispenses a fixed amount of liquid and accurately supplies a fixed amount of liquid. In addition to the screw dispenser 10, a mono dispenser or the like may also be used as the dispenser. The dispenser may also be a piston-type dispenser that has a piston structure that delivers the liquid 13 by reciprocating drive, or a dispenser of another type not listed here.

[0028] The screw dispenser 10 has a screw-type rotor 17, which is a liquid pressure-feeding unit 16, and a liquid storage unit 15 that stores the liquid 13. The screw-type rotor 17 is held inside the liquid storage unit 15 by a bearing 18 and rotates around a rotation axis 19. The screw dispenser 10 has a nozzle 11 at one end, and the liquid 13 is ejected from the tip of the nozzle 11 by pressure generated by the rotation of the screw-type rotor 17. The liquid 13 may be a viscous liquid that loses fluidity when heated and becomes a gel-like hardened product. The viscous liquid is, for example, a liquid with a viscosity of 0.1 [Pa·s] to 1000 [Pa·s].

[0029] Syringe 14 is an instrument used to inject and aspirate liquid or gas, and liquid agent 13 is retained in syringe 14 and sent to liquid agent storage section 15. A switching valve 20 is connected to syringe 14, and by opening switching valve 20, liquid agent 13 can be discharged to the outside.

[0030] The apparatus vacuum chamber 21 accommodates the screw dispenser 10 of the coating apparatus 1 and the apparatus to be coated 12 therein. The dispenser of the coating apparatus 1 may also be accommodated therein. The apparatus vacuum chamber 21 is made of an airtight material, such as glass, and can maintain a vacuum (for example, 13 Pa to 7000 Pa, more preferably 1.3 Pa to 700 Pa) inside. A vacuum pump (not shown) is connected to the apparatus vacuum chamber 21, and a vacuum space can be formed within the apparatus vacuum chamber 21 by operating the vacuum pump. Instead of evacuating the apparatus vacuum chamber 21, the pressure within the apparatus vacuum chamber 21 may be reduced.

[0031] Furthermore, although not shown in FIG. 1, the screw dispenser 10 is provided with a control unit that controls the position and movement speed of the screw dispenser 10, the delivery of the liquid agent 13, the amount of the liquid agent 13 discharged from the screw dispenser 10, and the rotation speed and direction of the screw-type rotor 17.

[0032] The control unit is composed of a CPU, RAM, ROM, etc., and performs various controls. The CPU is a central processing unit that executes various programs to achieve various functions. The RAM is used as the CPU's working area and storage area, and the ROM stores the operating system and programs executed by the CPU.

[0033] Next, the structures of the power semiconductor module and the physical quantity sensor will be described. FIG. 3 is a cross-sectional view showing the structure of the power semiconductor module according to the first embodiment. As shown in FIG. 3, in a power semiconductor module 44, a first conductive plate 33 made of copper or the like is disposed on one surface (front surface) of an insulating substrate 32, and a second conductive plate 34 made of copper or the like is disposed on the other surface (back surface) to form a laminated substrate 35. A plurality of power semiconductor chips 31 are mounted on the front surface of the first conductive plate 33 of the laminated substrate 35 via a bonding layer 41 made of solder or the like. Metal terminals 39 that output signals to the outside are bonded to the inside of a case 37. Furthermore, metal wires 40 made of aluminum or the like are attached to the front surface of the power semiconductor chips 31 via the bonding layer 41, electrically connecting the power semiconductor chips 31 and the metal terminals 39. A primer layer 43 is laminated on the sealed components, such as the power semiconductor chips 31, the laminated substrate 35, and the metal wires 40, to improve adhesion. A primer layer 43 is also provided inside the case 37, and sealing resin 38 is filled as a sealing material in contact with the primer layer 43. The sealing resin 38 is, for example, an epoxy resin, which is injected into the case 37 in a gel state and heated to harden, thereby protecting the power semiconductor chip 31 and the metal wire 40 from external moisture and the like.

[0034] 4 is a cross-sectional view showing the structure of the physical quantity sensor according to the first embodiment. In FIG. 4, only a sensor element 51 of a pressure sensor is shown as the physical quantity sensor. As shown in FIG. 4, the sensor element 51 includes a resin case 52, a pressure sensor chip (semiconductor chip) 53 housed in a recess of the resin case 52, a base member 54, and a diaphragm 59. The base member 54 and the pressure sensor chip 53 are joined by electrostatic bonding. The base member 54 and the resin case 52 are adhered with an adhesive 55. The lead terminals 57 are terminal pins for extracting signals from the sensor element 51, and multiple lead terminals 57 are arranged.

[0035] The lead terminals 57 are each integrally molded with the resin case 52. One end of each lead terminal 57 protrudes into the resin case 52 and is connected by bonding wires 55 to each electrode provided on a pad portion on the front surface of the pressure sensor chip 53.

[0036] The interior of the resin case 52 is filled with a sealing gel 58 as a sealant. The sealing gel 58 is, for example, a fluorine gel, and protects the pressure sensor chip 53, the bonding wires 55, and the lead terminals 57 from the pressure medium to be measured. The liquid injected to provide the sealing gel 58 may be, for example, SIFEL (registered trademark) manufactured by Shin-Etsu Chemical Co., Ltd.

[0037] The following describes in detail a method for injecting a liquid agent that will become the sealing resin 38 into the power semiconductor module 44 and a method for injecting a liquid agent that will become the gel member 58 into the sensor element 51 of the physical quantity sensor in the first embodiment.

[0038] In the step of injecting the liquid agent according to the first embodiment, first, syringe 14 is replaced, switching valve 20 is opened, and liquid agent 13 into which air has been mixed during the replacement is discharged (step S11: fifth step). By degassing liquid agent 13 in advance in this manner, it is possible to prevent air bubbles from being mixed in from the path from syringe 14 to screw dispenser 10.

[0039] Next, the device 12 to be coated is placed, and the device vacuum chamber 21 is evacuated (step S12: first process), creating a vacuum in the device vacuum chamber 21. Here, the device 12 to be coated is a power semiconductor module 44 or a sensor element 51 of a physical quantity sensor. Next, the coating pressure and coating time of the coating device 1 are set (step S13).

[0040] Next, after confirming the initial application amount, application is started (step S14: second process). For example, the switching valve 20 is closed, and the application device 1 injects the liquid agent 13 in the syringe 14 into the liquid agent storage section 15 in the screw dispenser 10. Next, the application device 1 rotates the rotation shaft 19 to rotate the screw-type rotor 17, which applies pressure to the liquid agent pressure-feeding section 16, and injects the liquid agent 13 from the nozzle 11 into the device 12 to be applied.

[0041] Next, the device vacuum chamber 21 is opened to the atmosphere, and the device 12 is removed (step S15: third process). This completes the injection of the liquid agent 13 into one device 12, and steps S13 to S15 are repeated for the number of devices 12.

[0042] In the first embodiment, as shown in FIG. 1, the apparatus vacuum chamber 21 is also arranged in the moving parts of the coating apparatus 1 (in FIG. 1, the liquid storage section 15, the liquid pressure-feeding section 16, the screw-type rotor 17, the bearing 18, and the rotating shaft 19). This makes it possible to place the moving parts of the coating apparatus 1 under vacuum, and even if air is entrained during the operation of the coating apparatus 1, the amount of entrained air is very small. Therefore, the reduction in entrained air reduces the likelihood of air bubbles being mixed in the coating apparatus 1. This significantly reduces the impact of air bubbles on product quality, and also makes it possible to reduce variations in the injection amount and suppress surrounding contamination.

[0043] Furthermore, the coating device 1 has a mechanism (for example, vacuuming after coating and reverse rotation after coating) that prevents dripping from the tip of the nozzle 11, so the liquid 13 does not leak out of the coating device 1. Furthermore, the gaps in the coating device 1 are the nozzle 11 and the parts that move during coating, but even if there is a small air leak from the moving parts during coating, the structure is such that there are no gaps that would allow the liquid 13, which has an overwhelmingly higher viscosity than air, to leak out.

[0044] Furthermore, a dedicated container such as a syringe 14 or a barrel is installed at the inlet for the liquid agent 13, and the liquid agent is introduced from the syringe 14 or the barrel. FIG. 1 shows an example of a syringe 14. The syringe 14 or the barrel has a threaded groove and is connected to the inlet by tightening, so that air does not enter the coating device 1. However, when refilling the liquid agent 13 (when replacing the syringe 14), a small amount of air may enter the connection part. In the first embodiment, when replacing the syringe 14, the switching valve 20 near the inlet for the liquid agent 13 is opened to discharge the liquid agent 13 containing air that has been generated during replacement, so that air does not enter the coating device 1.

[0045] As described above, according to the coating apparatus and the method for manufacturing a power semiconductor module and a physical quantity sensor of the first embodiment, the apparatus vacuum chamber is also disposed in the moving part of the coating apparatus. This allows the moving part of the coating apparatus to be placed under vacuum, and even if air is entrained during operation of the coating apparatus, the amount of entrained air is very small. This reduces the amount of entrained air, thereby reducing the likelihood of air bubbles being mixed into the coating apparatus. This significantly reduces the impact on product quality, and also makes it possible to reduce variations in the injection amount and suppress surrounding contamination.

[0046] (Embodiment 2) Fig. 5 is a cross-sectional view showing a method for manufacturing a power semiconductor module and a physical quantity sensor according to the second embodiment. Fig. 6 is a flowchart showing a method for manufacturing a power semiconductor module and a physical quantity sensor according to the second embodiment. In the second embodiment, as in the first embodiment, Figs. 5 and 6 show the step of injecting gel into the power semiconductor module and the physical quantity sensor. Other steps in the method for manufacturing a power semiconductor module and a physical quantity sensor are the same as those generally performed in the past, and therefore description thereof will be omitted.

[0047] In the second embodiment, instead of the entire coating device 1, the nozzle 11 of the coating device 1 and the device to be coated 12 are provided in a vacuum chamber 23, and movable parts such as the bearing 18 of the coating device 1 are provided in a movable part vacuum chamber 22. In the second embodiment, among the movable parts of the coating device 1, the bearing 18 that comes into contact with the atmosphere and the part of the rotating shaft 19 that protrudes to the outside from the liquid agent storage part 15 are provided in the movable part vacuum chamber 22. In addition, a vacuum pump (not shown) is connected to the movable part vacuum chamber 22 and the vacuum chamber 23, and a vacuum space can be formed in the movable part vacuum chamber 22 and the vacuum chamber 23 by operating the vacuum pump. The other configurations are the same as those in the first embodiment, and therefore description thereof will be omitted.

[0048] Hereinafter, in the second embodiment, a method for injecting the sealing resin 38 into the power semiconductor module 44 and a method for injecting the gel material 58 into the sensor element 51 of the physical quantity sensor will be described in detail. Here, Fig. 5 shows an example of the application device 1 equipped with a screw dispenser 10. Instead of the screw dispenser 10, a mohno dispenser or the like may also be used.

[0049] In the process of injecting the liquid agent according to the second embodiment, first, syringe 14 is replaced, switching valve 20 is opened, and liquid agent 13 into which air has been mixed during replacement is discharged (step S21: fifth process). By degassing liquid agent 13 in advance in this manner, it is possible to prevent air bubbles from being mixed in from the path from syringe 14 to screw dispenser 10.

[0050] Next, the movable part vacuum chamber 22 is evacuated (step S22: first process), and the movable part vacuum chamber 22 is evacuated. Next, the coating pressure and coating time of the coating device 1 are set (step S23). Next, the coated device 12 is placed in the vacuum chamber 23, and the vacuum chamber 23 is evacuated (step S24: second process), and the vacuum chamber 23 is evacuated. Here, the coated device 12 is a power semiconductor module 44 or a sensor element 51 of a physical quantity sensor.

[0051] Next, after confirming the initial application amount, application is started (step S25: third process). For example, the switching valve 20 is closed, and the application device 1 injects the liquid agent 13 in the syringe 14 into the liquid agent storage section 15 in the screw dispenser 10. Next, the application device 1 rotates the rotation shaft 19 to rotate the screw-type rotor 17, which applies pressure to the liquid agent pressure-feeding section 16, and injects the liquid agent 13 from the nozzle 11 into the device 12 to be applied.

[0052] Next, the vacuum chamber 23 is opened to the atmosphere, and the apparatus 12 to be coated is removed (step S26: fourth process). This completes the injection of the liquid agent 13 into one apparatus 12 to be coated, and steps S24 to S26 are repeated for the number of apparatuses 12 to be coated.

[0053] In the second embodiment, as shown in FIG. 5, a movable part vacuum chamber 22 is disposed in the movable part of the coating apparatus 1. This allows the movable part of the coating apparatus 1 to be placed under vacuum, and even if air is entrained during the operation of the coating apparatus 1, the amount of entrained air is very small. This reduces the amount of entrained air, thereby reducing the possibility of air bubbles being mixed into the coating apparatus 1. This significantly reduces the impact on product quality, and also makes it possible to reduce variations in the injection amount and to prevent contamination of the surrounding area. Furthermore, in the second embodiment, since only the movable part of the coating apparatus 1 is evacuated, the evacuation time can be shortened compared to the first embodiment, and a large-scale vacuum device is not required.

[0054] As described above, according to the coating device and the method for manufacturing a power semiconductor module and a physical quantity sensor of the second embodiment, the movable part vacuum chamber is disposed in the movable part of the coating device. Therefore, the same effects as those of the first embodiment are obtained. Furthermore, in the second embodiment, since only the movable part of the coating device is evacuated, the evacuation time can be shortened compared to the first embodiment, and a large-scale vacuum device is not required. [Industrial Applicability]

[0055] As described above, the coating device and the method for manufacturing a power semiconductor module and a physical quantity sensor according to the present invention are useful for power semiconductor modules used in power conversion devices such as inverters, power supply devices for various industrial machines, and automotive igniters, as well as physical quantity sensor devices equipped with sensor chips, and are particularly suitable for pressure sensor devices. [Explanation of symbols]

[0056] 1, 101 Coating device 10, 110 Screw dispenser 11, 111 nozzle 12, 112 Applicable equipment 13, 113 Liquid 14, 114 syringe 15, 115 Liquid storage section 16, 116 Liquid pressure feeding section 17, 117 Screw-type rotor 18, 118 bearings 19, 119 Rotation axis 20, 120 switching valve 21 Equipment vacuum chamber 22 Moving part vacuum chamber 23, 123 Vacuum chamber 31 Power semiconductor chips 32 Insulating substrate 33 First conductive plate 34 Second conductive plate 35 Laminated substrate 37 cases 38 Sealing resin 39 Metal terminal 40 Metal Wire 41 Bonding layer 42 Heat dissipation base 43 Primer layer 44 Power Semiconductor Module 51 Sensor element 52 Resin case 53 Pressure sensor chip 54 Base member 55 Bonding Wire 56 Insulating materials 57 Lead pin 58 Liquid 59 Diaphragm 124 Bubbles

Claims

1. a dispenser having a liquid medicine pressure-feeding unit that dispenses a fixed amount of the liquid medicine and a syringe that stores the liquid medicine; an apparatus vacuum chamber in which the dispenser and an apparatus to be coated, in which a semiconductor chip is disposed in a case, are placed and which can maintain a vacuum inside; Equipped with The dispenser has a screw-type rotor, a bearing, and a rotating shaft, and by rotating the rotating shaft, the screw-type rotor is rotated and the liquid agent is applied to the device to be coated.

2. a dispenser having a liquid medicine pressure-feeding unit that dispenses a fixed amount of the liquid medicine and a syringe that stores the liquid medicine; a vacuum chamber in which a coating target device having a case in which a semiconductor chip is disposed is placed and the inside of the vacuum chamber can be maintained; a movable part vacuum chamber in which the movable part of the dispenser is disposed and which can maintain a vacuum inside; Equipped with the dispenser has a screw-type rotor, a bearing, and a rotating shaft, and the bearing in contact with the atmosphere and a portion of the rotating shaft protruding from a liquid agent storage portion are provided in a vacuum chamber of the movable portion, A coating device characterized in that the rotation shaft is rotated to rotate the screw-type rotor, thereby coating the liquid agent onto the device to be coated.

3. a dispenser having a liquid medicine pressure-feeding unit that dispenses a fixed amount of the liquid medicine and a syringe that stores the liquid medicine; a coating apparatus including an apparatus vacuum chamber in which the dispenser and a coated apparatus including a power semiconductor module or a physical quantity sensor are placed and which can maintain a vacuum inside, a first step of placing the device to be coated in the device vacuum chamber and evacuating the device vacuum chamber; a second step of applying the liquid agent to the target device after evacuating the device vacuum chamber; a third step of opening the device vacuum chamber to the atmosphere after applying the liquid agent and removing the device to be coated; Including, The dispenser has a screw-type rotor, a bearing, and a rotating shaft; In the second step, the rotation shaft is rotated to rotate the screw-type rotor and apply the liquid agent to the device to be coated.

4. a dispenser having a liquid medicine pressure-feeding unit that dispenses a fixed amount of the liquid medicine and a syringe that stores the liquid medicine; a vacuum chamber in which a coating target device including a power semiconductor module or a physical quantity sensor is placed and which can maintain a vacuum inside; a movable part vacuum chamber in which the movable part of the dispenser is disposed and which can maintain a vacuum inside, a first step of evacuating the movable part vacuum chamber; a second step of placing the device to be coated in the vacuum chamber and evacuating the vacuum chamber; a third step of applying the liquid agent to the device to be coated after evacuating the movable part vacuum chamber and the vacuum chamber; a fourth step of opening the vacuum chamber to the atmosphere after applying the liquid agent and removing the device to be coated; Including, the dispenser has a screw-type rotor, a bearing, and a rotating shaft, and the bearing in contact with the atmosphere and a portion of the rotating shaft protruding from a liquid agent storage portion are provided in a vacuum chamber of the movable portion, In the third step, the rotation shaft is rotated to rotate the screw-type rotor and apply the liquid agent to the device to be coated.

5. 5. The method for manufacturing a power semiconductor module and a physical quantity sensor according to claim 3, further comprising a fifth step of replacing the syringe and discharging the liquid that has become air-mixed during the replacement from the syringe prior to the first step.

6. The method for manufacturing a power semiconductor module and a physical quantity sensor according to any one of claims 3 to 5, characterized in that the liquid agent is applied to areas where semiconductor chips and metal wires are connected in the power semiconductor module and the physical quantity sensor.

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