JP5147344B2 - Circuit device and manufacturing method thereof - Google Patents

Description

  The present invention relates to a circuit device and a manufacturing method thereof, and more particularly to a circuit device having a configuration in which a hybrid integrated circuit formed on an upper surface of a circuit board is sealed with a case material and a manufacturing method thereof.

  With reference to FIG. 10, a configuration of a configuration integrated circuit device 150 in which the case material 111 is employed will be described. The hybrid integrated circuit device 150 includes a substrate 101 made of a metal such as aluminum, an insulating layer 102 formed to cover the upper surface of the substrate 101, a conductive pattern 103 formed on the upper surface of the insulating layer 102, and a conductive pattern. 103 is provided with a circuit element 110 such as a transistor electrically connected to 103. The circuit element 110 is sealed by the case material 111 and the sealing resin 108.

Specifically, the case material 111 has a substantially frame shape and is in contact with the side surface of the substrate 101. Further, the upper end portion of the case material 111 is positioned above the upper surface of the substrate 101 in order to secure a space for sealing on the upper surface of the substrate 101. A space surrounded by the case material 111 above the substrate 101 is filled with a sealing resin 108, and the circuit element 110 such as a semiconductor element is covered with the sealing resin 108. With this configuration, even when the substrate 101 is relatively large, the circuit element in which the upper surface of the substrate 101 is embedded is resin-sealed by filling the space surrounded by the case material 111 and the like with the sealing resin 108. be able to.
JP 2007-036014 A

  In the hybrid integrated circuit device 150 described above, a power transistor such as an IGBT (Insulated Gate Bipolar Transistor) and a driver IC for driving the power transistor are mounted on the upper surface of the substrate 101. A control element such as a microcomputer for controlling the driver IC is mounted on the mounting board side on which the hybrid integrated circuit device 150 is mounted. Therefore, there is a problem that the area required for mounting a circuit for controlling driving of a load such as a motor is large on the mounting substrate side.

  As a configuration for improving the mounting density of the hybrid integrated circuit device 150, a configuration in which a plurality of substrates 101 are provided so as to overlap inside the case material 111 and a circuit element is incorporated in each substrate 101 is conceivable. However, it has been difficult to provide a plurality of substrates 101 in the case material 111 in this way and individually seal the circuit elements disposed on the upper surface of each substrate.

  An object of the present invention is to provide a circuit device capable of efficiently resin-sealing a plurality of circuit boards that are stacked on a case material and a method for manufacturing the circuit device.

The circuit device of the present invention is incorporated in the case material, the case material, the first circuit board having the first conductive pattern formed on the surface thereof, and the first circuit board so as to overlap with the case material. And a second circuit board having a second conductive pattern formed on the surface, a first circuit element mounted on the first circuit board and electrically connected to the first conductive pattern, and the second circuit board. A second circuit element mounted on the second conductive pattern and electrically connected to the second conductive pattern; and a sealing resin formed on a surface of the second circuit board so that the second circuit element is sealed; A lead having one end connected to the first conductive pattern on the surface of the first circuit board and penetrating through a through-hole provided in the second circuit board, the other end being led out; and the first circuit board , The second circuit board and the case material Comprising a Murrell hollow portion, the lead, the first lead being the second circuit upper surface mounted connection the second circuit element and electrically the substrate, it is mounted on the second circuit board And a second lead that is not electrically connected to the second circuit element, and a solder is filled in a gap between the first lead and the through hole of the second circuit board, and the second lead The gap between the through hole is filled with solder .

In the method of manufacturing a circuit device according to the present invention, a first circuit board in which a first conductive pattern and a first circuit element are incorporated on a surface and a lead is fixed to a pad made of the first conductive pattern is incorporated in a case material. a step, a second circuit board having a through hole formed with the second conductive pattern and the second circuit element is incorporated in the surface, seen write set in the case member by penetrating the lead into the through-hole, and the second A step of forming a hollow portion surrounded by one circuit board, the second circuit board and the case material; and a surface of the second circuit board so as to cover the second conductive pattern and the second circuit element. Forming a sealing resin, wherein the lead includes a first lead electrically connected to the second circuit element mounted on an upper surface of the second circuit board, and the second circuit. On the board A second lead that is not electrically connected to the mounted second circuit element is included, and a bonding material is applied to both the through hole through which the first lead penetrates and the through hole through which the second lead penetrates. The through hole is blocked.

  In the present invention, the first circuit board and the second circuit board are provided inside the case material, and the lead having one end fixed to the first circuit board is led out through the through hole provided in the second circuit board. I am letting. Further, the lead includes a first lead connected to the second circuit element fixed to the second circuit board and a second lead not connected. In the present invention, the gap between the first lead and the through hole is filled with the bonding material, and the bonding material is also filled between the second lead and the through hole. By doing so, even if a semi-solid or liquid sealing resin is applied to the upper surface of the second circuit board, a problem that the liquid sealing resin leaks through the through hole is prevented.

  With reference to FIG. 1, a configuration of a hybrid integrated circuit device 10 will be described as an example of a circuit device. FIG. 1A is a cross-sectional view of the hybrid integrated circuit device 10, FIG. 1B is a perspective view showing a location where the first lead 28A penetrates the second circuit board 20, and FIG. FIG. 6 is a perspective view showing a location where a second lead 28B penetrates the second circuit board 20.

  Referring to FIG. 1A, the hybrid integrated circuit device 10 has a configuration in which a first circuit board 18 and a second circuit board 20 are superimposed on a case material 12 and incorporated. A first circuit element 22 (for example, a power transistor) is disposed on the upper surface of the first circuit board 18, and a second circuit element (for example, a microcomputer) is disposed on the upper surface of the second circuit board 20. Furthermore, the lead 28 fixed to the pad 38 </ b> A of the first circuit board 18 is configured to penetrate the second circuit board 20 and lead out to the outside.

  The case material 12 is formed by injection molding a thermosetting resin such as an epoxy resin or a thermoplastic resin such as an acrylic resin, and has a generally frame shape. Referring to FIG. 1A, the upper surface and the lower surface of the case material 12 are openings, the opening on the upper surface is closed by the second circuit board 20, and the opening on the lower surface is formed by the first circuit board 18. It is blocked. In addition, holes for screwing are provided in the left and right ends of the case material 12.

  The first circuit board 18 is incorporated in the opening at the bottom of the case material 12 and is made of aluminum (Al), copper (Cu), or an alloy mainly composed of these metals. Here, the first circuit board 18 is composed of two metal substrates made of aluminum, but the first circuit board 18 may be composed of one metal substrate. Details of the first circuit board 18 will be described with reference to FIG.

  The second circuit board 20 is incorporated in an opening in the upper part of the case material 12, and a printed circuit board (PCB) is employed. Specifically, a paper phenol substrate, a glass epoxy substrate, or the like is employed as the second circuit substrate 20. Further, a substrate made of ceramic may be adopted as the second circuit substrate 20. Furthermore, the second conductive pattern 21 may be formed only on the upper surface of the second circuit board 20, or the second conductive pattern 21 may be provided on both surfaces. Furthermore, the second conductive pattern 21 laminated in three or more layers may be configured on the second circuit board 20. The second circuit board 20 is provided with a through hole for allowing the lead 28 to pass therethrough.

  As the second circuit element 24 mounted on the second circuit board 20, a microcomputer or the like that generates less heat than the first circuit element 22 mounted on the first circuit board 18 is mounted. Therefore, as the second circuit board 20, an inexpensive printed board that is inferior in thermal conductivity can be employed. In addition, since the cost of design change and manufacturing of the printed circuit board is low, the shape of the conductive pattern of the second circuit board 20 can be changed even if the specifications of the microcomputer or the like employed as the second circuit element 24 are changed. It can be easily handled. Furthermore, the second circuit board 20 made of an insulating material such as epoxy resin has a lower thermal conductivity than the first circuit board 18 made of metal. Therefore, the conduction of heat by the second circuit board 20 is suppressed, whereby the heat generated from the first circuit element 22 that is a power transistor is suppressed from being conducted to the second circuit element 24 that is a microcomputer.

  The first circuit element 22 is an element that is electrically connected to the first conductive pattern 38 formed on the upper surface of the first circuit board 18. As the first circuit element 22, for example, a power transistor that switches a current of 1 ampere or more is employed. Here, a bipolar transistor, a field effect transistor (FET), or an insulated gate bipolar transistor (IGBT) is employed as the power transistor. Furthermore, as the first circuit element 22, elements other than transistors can be generally employed. For example, active elements such as LSIs and diodes, and passive elements such as chip capacitors and chip resistors are employed.

  In addition, when the first circuit element 22 is a semiconductor element such as a power transistor, the back surface thereof is fixed via a conductive adhesive such as solder. Furthermore, a heat sink made of a metal such as copper may be provided between the first circuit element 22 and the first conductive pattern 38. The electrodes formed on the upper surface of the first circuit element 22 are connected to the first conductive pattern 38 via the fine metal wire 42.

  Further, as the first circuit element 22, a diode constituting a rectifier circuit, a coil or a capacitor constituting a smoothing circuit, a driver IC for applying a control signal to the control electrode of the power transistor described above, a thermistor, or the like is employed.

  The second circuit element 24 is an element that is electrically connected to the second conductive pattern 21 formed on the surface of the second circuit board 20, and generally has a lower operating temperature than the first circuit element described above. An element is adopted. As a specific example, for example, a microcomputer or an aluminum electrolytic capacitor is mounted on the second circuit board 20 as the second circuit element 24. Further, as the second circuit element 24, as in the first circuit element 22, active elements and passive elements are generally employed. Further, as the second circuit element 24, a crystal oscillator or a semiconductor memory may be adopted. Furthermore, the second circuit element 24 may be fixed only to the upper surface of the second circuit board 20, may be fixed only to the lower surface, or may be fixed to both surfaces.

  Referring to FIG. 1B, an LSI as a microcomputer is mounted on the upper surface of the second circuit board 20 in a resin-sealed package state. However, the microcomputer may be fixed to the second conductive pattern 21 formed on the surface of the second circuit board 20 in a bare chip state.

The first sealing resin 14 is formed so as to cover the entire upper surface of the first circuit element 22 and the first circuit board 18. The first sealing resin 14 is made of a resin material such as an epoxy resin mixed with a filler such as alumina (Al ₂ O ₃ ) or silica (SiO ₂ ). Thus, the moisture resistance of the first circuit element 22 is improved by sealing the first circuit element 22 with the first sealing resin 14. Furthermore, since the connection location (made of a bonding material such as solder) between the first circuit element 22 and the first conductive pattern 38 is covered with the first sealing resin 14, the vibration resistance of this connection location is improved. Is done. Further, the first sealing resin 14 made of a resin mixed with a filler has a light-shielding property that does not transmit light. Therefore, by covering the first conductive pattern 38 and the first circuit element 22 formed on the upper surface of the first circuit board 18 with the light-shielding first sealing resin 14, the shape of the first conductive pattern 38 and the first conductive pattern 38. The position of the circuit element 22 can also be concealed. Here, referring to FIG. 1 (B), the first sealing resin 14 is formed so as to cover the first circuit elements 22 and the fine metal wires 42 used for the connection. However, the first circuit element 22 need not be completely covered by the first sealing resin 14. That is, the connection portion between the first circuit element 22 and the first conductive pattern 38 is covered with the first sealing resin 14, and the upper end portion of the first circuit element 22 protrudes upward from the upper surface of the first sealing resin 14. May be.

  Further, the first sealing resin 14 is formed inside the side wall of the case material 12 and in a space surrounded by the first circuit board 18 and the second circuit board 20, but to the extent that this space is completely filled. Not formed. Therefore, a hollow portion 26 that is not filled with the first sealing resin 14 is provided in the internal space of the case material 12. In addition, since the first circuit element 22 is sealed by the internal space of the case material 12, the hybrid integrated circuit device 10 may be configured without the first sealing resin 14.

  Further, the hollow portion 26 may be sealed by the case material 12, the first circuit board 18 and the second circuit board 20, or may be communicated with the outside. When the hollow portion 26 communicates with the outside, a communication hole that communicates the hollow portion 26 with the outside may be provided in the side wall portion of the case material 12, between the case material 12 and the second circuit board 20, or the like. good.

  The second sealing resin 16 (sealing resin) is formed so as to cover the entire upper surface of the second circuit element 24 and the second circuit board 20, and filler is mixed in the same manner as the first sealing resin 14. Made of resin material. By covering the second circuit element 24 and the second circuit board 20 with the second sealing resin 16, the moisture resistance and vibration resistance of the second circuit element 24 are improved, and the second circuit board 20 is formed on the upper surface of the second circuit board 20. The shape of the provided second conductive pattern 21 and the arrangement of the second circuit elements 24 are concealed. Here, the second sealing resin 16 does not necessarily need to be formed so that the second circuit element 24 is completely covered, and a connection portion between the second circuit element 24 and the second conductive pattern 21 is covered, The upper part of the second circuit element 24 may be formed so as to protrude upward from the upper surface of the second sealing resin 16.

  The lower end of the lead 28 is fixed to a pad 38 </ b> A made of the first conductive pattern 38 formed on the upper surface of the first circuit board 18. The pad 38A and the lower end of the lead 28 are bonded via a conductive adhesive such as solder. The lead 28 penetrates through the first sealing resin 14, the second circuit board 20, and the second sealing resin 16, and the upper end is led out to the outside. Here, the lead 28 is connected to the second circuit element 24 fixed to the upper surface of the second circuit board 20 at the place where the lead 28 penetrates the second circuit board 20 and the case where it is not connected. There is. When the lead 28 is connected to the second circuit element 24, the second circuit element 24 mounted on the second circuit board 20 and the first circuit board 18 mounted on the first circuit board 18 via the lead 28. The circuit element 22 may be electrically connected. In addition, as a case where the lead 28 and the second circuit element 24 are not connected, for example, when a power supply current is supplied to the inverter circuit provided on the first circuit board 18 from the outside, or to the first circuit board 18 It can be considered that the current converted by the provided inverter circuit passes through the lead 28 and is supplied to the outside.

  In the following description, the lead 28 electrically connected to the second circuit element 24 mounted on the second circuit board 20 is referred to as a first lead 28A, and the lead 28 not electrically connected to the second circuit element 24 is referred to as the first lead 28A. This is referred to as a second lead 28B.

  The lower end of the lead 30 is connected to the second conductive pattern 21 provided on the upper surface of the second circuit board 20, and the upper end protrudes upward through the second sealing resin 16. The vicinity of the lower end of the lead 30 is inserted and fixed in a hole provided through the second circuit board 20, and an electric signal input / output to / from the second circuit element 24 mounted on the second circuit board 20. Has the function of passing through. Here, the second conductive pattern 21 formed on the upper surface of the second circuit board 20 and the lead 30 are connected via a conductive adhesive such as solder.

  FIG. 1B shows a perspective view of a portion where the first lead 28 </ b> A penetrates the second circuit board 20. A through hole 15 is provided partially through the second circuit board 20, and a pad 21 </ b> A made of an annular conductive pattern is formed so as to surround the through hole 15. Furthermore, a metal film covering the inner wall of the through hole 15 may be formed of a plating film continuously with the pad 21A. Furthermore, a conductive pattern having the same shape as the pad 21 </ b> A may be formed on the lower surface of the second circuit board 20.

  A conductive bonding material 17 is filled in a gap between the through hole 15 and the first lead 28A, and the first lead 28A is electrically connected to the pad 21A through the bonding material 17. Further, the pad 21 </ b> A is electrically connected to the second circuit element 24 placed on the upper surface of the second circuit board 20 via the wiring 21 </ b> B made of the second conductive pattern 21.

  Here, as the bonding material 17, a conductive bonding material such as a conductive paste or solder (brazing material) composed of a resin mixed with a powder made of a conductive material such as silver is employed.

  FIG. 1C shows a perspective view of a portion where the second lead 28 </ b> B penetrates the second circuit board 20. Here, an annular pad 21A is provided on the upper surface of the second circuit board 20 so as to surround the through hole 15, and the inner wall of the through hole 15 is covered with a metal film continuous with the pad 21A. Here, the wiring 21B as shown in FIG. 1B does not exist from the pad 21A, and the pad 21A is formed independently of other surrounding second conductive patterns 21. Thus, the second lead 28B is not electrically connected to the second circuit element 24 placed on the second circuit board 20.

  In the present embodiment, the bonding material 17 is filled between the second lead 28B and the through hole 15 as in the case of the first lead 28A. Here, as the bonding material 17, a conductive bonding material such as a conductive paste or solder can be employed. Furthermore, since it is not necessary for the second lead 28B to be electrically connected to the pad 21A, an insulating bonding material made of a resin material may be employed as the bonding material 17. Although described in detail later, the purpose of filling the bonding material 17 between the second lead 28 </ b> B and the through hole 15 is to close the through hole 15.

  In the present embodiment, referring to FIG. 1C, the bonding material 17 is filled in the gap between the second lead 28 </ b> B and the through hole 15. This prevents resin leakage in the middle of the manufacturing process. In general, the circuit element placed on the upper surface of the second circuit board 20 and the second lead 28B do not need to be electrically connected, so that the bonding material 17 is interposed between the through hole 15 and the second lead 28B. Need not be filled. In this way, the through hole formed only for the purpose of penetrating the lead is referred to as a “hole”. However, if the gap between the second lead 28B and the side wall of the through hole 15 is left as it is, the upper surface of the second circuit board 20 is covered with the second sealing resin 16 in this step. There arises a problem that the resin leaks from the gap. That is, in this step, the semi-solid or liquid second sealing resin 16 is applied to the entire upper surface of the second circuit board 20 and then cured by heating, but from the gap between the second lead 28B and the through hole 15. The semi-solid or liquid second sealing resin 16 leaks into the hollow portion 26.

  In order to avoid this problem, in this embodiment, the bonding material 17 is filled in the gap between the second lead 28 </ b> B and the side wall of the through hole 15. By doing so, the bonding material 17 is filled in the gaps between all the leads 28 and the through holes 15, and the resin leakage described above is prevented, so that the resin material is prevented from entering the hollow portion 26. .

  Further, in the hybrid integrated circuit device 10 described above, by providing the hollow portion 26, the first circuit element 22 mounted on the first circuit board 18 and the second circuit element 24 mounted on the second circuit board 20 are provided. The thermal interference of is suppressed. This matter will be described below.

  Specifically, in the present embodiment, two superposed circuit boards (the first circuit board 18 and the second circuit board 20) are provided, and circuit elements are incorporated into the respective circuit boards so that the power transistor The configured power block and the control block for controlling the power block are built in the hybrid integrated circuit device 10 which is one package. And in order to improve moisture resistance and vibration resistance, it is necessary to seal the circuit element mounted on each circuit board with sealing resin. For example, referring to FIG. 1A, a first sealing resin 14 is formed inside the case material 12 so as to cover the first circuit element 22 disposed on the first circuit board 18, and further, A second sealing resin 16 is formed so as to cover the second circuit element 24 fixed to the upper surface of the two-circuit board 20.

  However, for example, when a power transistor is employed as the first circuit element 22 and a microcomputer is employed as the second circuit element, the microcomputer may malfunction due to heat generated from the power transistor. Specifically, during the operation of the hybrid integrated circuit device 10, the temperature Tc outside the device is compensated to be 100 ° C. or less, and the temperature (Tj) of the first circuit element 22 incorporated in the device is It is compensated to be 150 ° C. or lower. On the other hand, the upper limit of the operating temperature of the microcomputer that is the second circuit element 24 is lower than that of a power transistor such as IGBT, and is, for example, 85 ° C. or less. Therefore, when the first sealing resin 14 is formed so that the internal space of the case material 12 is completely filled, the heat generated from the first circuit element 22 is transmitted by the microcomputer via the first sealing resin 14. Conducted to a certain second circuit element 24. As a result, the second circuit element 24, which is a microcomputer, is heated to 85 ° C. or higher, and its operation may become unstable.

  Therefore, in this embodiment, the first sealing resin 14 that seals the first circuit element 22 does not completely fill the inside of the case material 12 and is a hollow portion that is an unfilled region that is not filled with the first sealing resin 14. 26 is provided inside the case member 12. Air is present in the hollow portion 26. Therefore, even if the heat generated from the first circuit element 22 as the power transistor is conducted to the first sealing resin 14, the heat conduction is blocked by the hollow portion 26 made of air having a high thermal resistance. Conduction to the second circuit element 24 (microcomputer) is suppressed. For this reason, the temperature of the second circuit element 24, which is a microcomputer, is suppressed from being heated to an upper limit (for example, 85 degrees) of the operating temperature, and the microcomputer operates in a stationary state.

  The external appearance of the hybrid integrated circuit device 10 will be further described with reference to FIG. 2A is a perspective view showing the appearance of the hybrid integrated circuit device 10, and FIG. 2B is a cross-sectional view taken along the line B-B 'of FIG. 2B.

  2A and 2B, the opening on the front side of the case material 12 is entirely covered with the second sealing resin 16, and the second sealing resin 16 A lead 28 and a lead 30 are led out from the surface to the outside. Details of the lead 28 and the lead 30 are as described above. The lead 28 and the lead 30 function as connection means for connecting a circuit provided inside the hybrid integrated circuit device 10 and the outside.

  The configuration of the first circuit board 18 will be described with reference to FIG. In the present embodiment, the first circuit board 18 is configured by laminating the mounting board 32 and the insulating board 34.

The mounting substrate 32 is a metal substrate mainly made of aluminum (Al) with a thickness of about 1.0 mm to 2.0 mm, and the upper surface and the lower surface are covered with an anodized film (a film made of Al ₂ O ₃ ). Has been. The upper surface of the mounting substrate 32 is covered with an insulating layer 36 made of a resin material such as an epoxy resin highly filled with a filler. The thickness of the insulating layer 36 is about 50 μm, for example. Further, a first conductive pattern 38 made of copper having a thickness of about 50 μm is formed on the upper surface of the insulating layer 36, and the first circuit element 22 is mounted on the first conductive pattern 38.

  Further, the exposed portion 13 is provided by partially removing the insulating layer 36 described above, and the mounting substrate 32 exposed from the exposed portion 13 and the first conductive pattern 38 are connected via the fine metal wire 42. Has been. Thus, by connecting the mounting substrate 32 and the first conductive pattern 38 via the exposed portion 13, the potential of the mounting substrate 32 can be set to a fixed potential (ground potential or power supply potential). By 32, the effect of shielding noise from the outside can be further increased. Furthermore, since a part of the first conductive pattern 38 and the mounting substrate 32 have the same potential, it is possible to reduce the parasitic capacitance generated between them.

  The back surface of the mounting substrate 32 configured as described above is attached to the upper surface of the insulating substrate 34 through an adhesive made of silicon resin.

  The insulating substrate 34 is made of a metal such as aluminum like the mounting substrate 32, and has a planar size larger than that of the mounting substrate 32. Therefore, the end portion of the insulating substrate 34 and the end portion of the mounting substrate 32 are arranged apart from each other. The upper surface of the insulating substrate 34 is covered with an insulating layer 40 made of a resin material such as polyimide resin. Furthermore, the lower surface of the insulating substrate 34 is located on the same plane as the lower end of the side wall of the case material 12.

  As described above, by stacking the mounting substrate 32 and the insulating substrate 34 to form the first circuit substrate 18, it is possible to achieve both the heat dissipation and pressure resistance of the first circuit substrate 18 at a high level. Specifically, as described above, since the mounting substrate 32 is connected to the first conductive pattern 38 and connected to, for example, the ground potential, if the back surface of the mounting substrate 32 is exposed to the outside, a short circuit may occur. . An insulating substrate 34 is provided to prevent this short circuit. The upper surface of the insulating substrate 34 and the lower surface of the mounting substrate 32 are insulated by an insulating layer 40 provided on the upper surface of the insulating substrate 34. Further, the side surface of the mounting substrate 32 and the side surface of the insulating substrate 34 are surfaces from which a metal material such as aluminum constituting each substrate is exposed, but the end portion (side surface) of the insulating substrate 34 and the end portion of the mounting substrate 32. By separating (side surfaces) from each other, the side surfaces of the substrates are prevented from being short-circuited.

  Furthermore, since both the mounting substrate 32 and the insulating substrate 34 are made of a metal such as aluminum having excellent heat dissipation, the heat generated from the first circuit element 22 is satisfactorily transferred to the outside via the mounting substrate 32 and the insulating substrate 34. Released.

  With reference to FIG. 4, another embodiment of the hybrid integrated circuit device 10 will be described. Here, the second circuit element 24 is mounted on both the upper surface and the lower surface of the second circuit board 20. And the 2nd sealing resin 16 is formed so that both the upper surface and lower surface of these 2nd circuit elements 24 and the 2nd circuit board 20 may be coat | covered.

  As described above, by providing the second circuit element 24 also on the lower surface of the second circuit board 20, a larger number of circuit elements can be built in the hybrid integrated circuit device 10. Furthermore, the second circuit element 24 provided on the back surface of the second circuit board 20 is sealed with the second sealing resin 16, so that the moisture resistance and vibration resistance of these elements are improved.

  Next, an example of a circuit constructed in the hybrid integrated circuit device 10 will be described with reference to FIG. Here, an inverter circuit including a switching circuit 45 composed of a plurality of power transistors is formed on the first circuit board 18, and the second circuit element 24 (microcomputer) in which a control circuit for controlling the inverter circuit is configured is the second circuit. It is mounted on the substrate 20. More specifically, the rectifier circuit 41, the smoothing circuit 43, the switching circuit 45, and the driver IC 44 are incorporated in the first circuit board 18.

  The operation of each circuit incorporated in the hybrid integrated circuit device 10 is as follows. First, the second circuit element 24 (microcomputer) mounted on the second circuit board 20 is input with a reference signal having a frequency corresponding to the rotational speed, and three pulse width modulated signals each having a phase difference of 120 degrees. A sinusoidal control signal is generated. The control signal generated by the second circuit element 24 is input to the first circuit board 18 via the lead 28 (see FIG. 2A).

  The control signal input to the first circuit board 18 is boosted to a predetermined voltage by the driver IC 44 and then applied to the control electrode of a power transistor (for example, IGBT) constituting the switching circuit 45.

  On the other hand, AC power input from the outside is converted into DC power by the rectifier circuit 41, and then the voltage is made constant by the smoothing circuit 43 and input to the switching circuit 45.

  From the switching circuit 45, three-phase pulse width modulated sine wave voltages (U, V, W) each having a phase difference of 120 degrees are generated and supplied to the motor 46. As a result, a load current that approximates a sine wave flows through the motor 46, and the motor 46 rotates at a predetermined rotational speed.

  Here, the signal passing through the first lead 28A shown in FIG. 1B corresponds to a control signal supplied from the second circuit element 24 (microcomputer) to the driver IC 44, for example. Further, the signal passing through the second lead 28B shown in FIG. 1C corresponds to the power supply current input from the outside to the rectifier circuit 41 (inverter circuit) or the AC current converted by the switching circuit 45. To do.

  Next, the configuration of the outdoor unit 48 of the air conditioner (air conditioner) in which the hybrid integrated circuit device 10 having the above configuration is incorporated will be described with reference to FIG.

  The outdoor unit 48 is configured such that a condenser 54, a fan 56, a compressor 52, and the hybrid integrated circuit device 10 are mainly built in a housing 50.

  The compressor 52 has a function of compressing a refrigerant such as ammonia using the driving force of the motor. And the refrigerant | coolant compressed by the compressor 52 is sent to the condenser 54, and when the fan 56 blows a wind on the condenser 54, the heat contained in the refrigerant | coolant inside the condenser 54 is discharge | released outside. Further, after the refrigerant is expanded, it is sent to the evaporator in the room to cool the air in the room.

  The hybrid integrated circuit device 10 of this embodiment has a function of controlling the rotation of a motor that drives the compressor 52 or the fan 56, and is fixed to a mounting substrate 60 provided inside the outdoor unit 48.

  FIG. 6B shows a structure to which the hybrid integrated circuit device 10 is attached. Here, the lead 28 and the lead 30 are inserted and mounted on the mounting substrate 60. The back surface of the first circuit board 18 on which the power transistor is mounted is in contact with the smooth surface of the heat sink 58. The hybrid integrated circuit device 10 can be attached to the heat sink 58 by screwing the case material 12 of the hybrid integrated circuit device 10 to the heat sink 58. Here, the heat sink 58 is formed by integrally molding a metal such as copper or aluminum, and the surface in contact with the hybrid integrated circuit device 10 is a smooth surface and the opposite surface is an uneven surface. . With this configuration, the heat generated from the first circuit element 22 that is a power transistor is conducted to the internal space of the outdoor unit 48 via the first circuit board 18 and the heat sink 58, and finally the fan 56 blows air. It is discharged to the outside of the outdoor unit 48 by the action.

  Next, a method for manufacturing the hybrid integrated circuit device 10 having the configuration shown in FIG. 1 will be described with reference to FIGS.

  Referring to FIG. 7A, first, the first circuit board 18 having a predetermined hybrid integrated circuit incorporated on the upper surface is incorporated into the case material 12.

  A first conductive pattern 38 having a predetermined shape is incorporated in advance on the upper surface of the first circuit board 18, and a first circuit element 22 such as a power transistor is mounted on a predetermined portion of the first conductive pattern 38. Are electrically connected. Further, the lead 28 is fixed to the pad-like first conductive pattern 38 via a conductive adhesive such as solder. Here, the lead 28 may be fixed to the first conductive pattern 38 in a state of a lead frame in which a plurality of leads 28 are connected.

  The first circuit board 18 having such a configuration is incorporated into the case material 12 so as to close the opening at the bottom of the case material 12. The details of the first circuit board 18 are as described above, and are configured by combining two metal boards as shown in FIG. However, the first circuit board 18 may be formed from a single metal substrate.

  With reference to FIG. 7B, next, the first sealing resin 14 is formed so that the upper surfaces of the first circuit element 22 and the first circuit substrate 18 are covered. Specifically, the liquid or semi-solid first sealing resin 14 is supplied to the inside of the case material 12 so that the first circuit element 22 is sealed and the upper surface of the first circuit board 18 is covered. . The first sealing resin 14 is made of a resin material mixed with a filler. When the resin material constituting the first sealing resin 14 is a thermosetting resin, a process for heating and curing the first sealing resin 14 applied to the upper surface of the first circuit board 18 is required.

  Referring to FIGS. 8A, 8B, and 8C, next, the second circuit board 20 in which the predetermined second circuit element 24 is incorporated is incorporated into the case material 12. FIG.

  Referring to FIG. 8A, a second conductive pattern 21 having a predetermined shape is formed on the upper surface of the second circuit board 20, and a second portion such as a microcomputer is provided at a predetermined portion of the second conductive pattern 21. The circuit element 24 is fixed.

  Further, a through hole 15 provided by opening the second circuit board 20 by drilling or laser irradiation processing is provided at a position corresponding to the lead 28 of the second circuit board 20. A pad 21 </ b> A made of a part of the second conductive pattern 21 is formed around the through hole 15.

  The second circuit board 20 having such a configuration is incorporated into the case material 12 so as to close the upper opening of the case material 12. The peripheral portion of the lower surface of the second circuit board 20 and the case material 12 are bonded via an insulating adhesive. Further, in this step, when the second circuit board 20 is incorporated into the case material 12, the lead 28 is simultaneously passed through the through hole 15 provided in the second circuit board 20.

  As the lead 28, the first lead 28A (see FIG. 8B) electrically connected to the second circuit element 24 fixed to the second circuit board 20 is not connected to the second circuit element 24. The second lead (see FIG. 8C) that is a lead can be classified.

  Referring to FIG. 8B, in this step, the bonding material 17 is filled in the gap between the side wall of the through hole 15 and the first lead 28A. As the bonding material 17, a conductive adhesive such as a conductive paste or solder is employed. As a specific method for forming the bonding material 17, the bonding material 17 is applied in advance to each through hole 15 of the second circuit board 20, and then the lead 28 is passed through each through hole 15. Alternatively, after the lead 28 is passed through the through hole 15, the bonding material 17 is filled in the gap between each through hole 15 and the lead 28. Here, when the bonding material 17 is made of solder, it is necessary to apply a solder cream to the through-hole 15 and then heat and melt the solder cream to form solder.

  Such a configuration is the same for the second lead 28 </ b> B shown in FIG. 8C, and the bonding material 17 is filled between the second lead 28 </ b> B and the through hole 15. Here, if the bonding material 17 applied to the first lead 28A and the bonding material 17 applied to the second lead 28B are made of the same material (for example, solder), the bonding material 17 is supplied to each through hole 15. There is an advantage that can be performed collectively.

  As described above, in this embodiment, both the first lead 28A and the second lead 28B are filled with the bonding material 17 in the gaps of the through holes 15 into which these leads are inserted. Specifically, since the first lead 28A needs to be electrically connected to the second circuit element 24 disposed on the upper surface of the second circuit board 20, the first lead 28A passes through the bonding material 17 made of solder or the like. Connected to the pad 21A. Here, the pad 21A is connected to the second circuit element 24 via the wiring 21B. On the other hand, referring to FIG. 8C, the second lead 28B does not need to be connected to an element on the second circuit board 20, and therefore, if only the electrical connection inside the device is considered, the second lead 28B is used. The bonding material 17 does not need to be filled in the through hole 15 into which 28B is inserted. However, in the present embodiment, the bonding material 17 is also filled in the through hole 15 through which the second lead 28B passes in order to prevent resin leakage through the through hole 15 in a later process.

  With reference to FIG. 8A, all the through holes 15 provided in the second circuit board 20 are closed by the bonding material 17 by doing in this way.

  Referring to FIG. 9, next, the second sealing resin 16 is formed so that the upper surfaces of the second circuit element 24 and the second circuit board 20 are sealed. Here, a predetermined amount of the second sealing resin 16 is supplied from the lower end of the nozzle 62 to a space surrounded by the upper surface of the second circuit board 20 and the inside of the side wall of the case material 12, and heating or the like is performed as necessary. Apply curing. The second sealing resin 16 is made of a thermoplastic resin or a thermosetting resin mixed with a filler such as granular alumina.

  The second sealing resin 16 supplied from the nozzle 62 to the upper surface of the second circuit board 20 is in a liquid or semi-solid state. Therefore, if there is a gap between the through hole 15 provided through the second circuit board 20 and the lead 28, the second sealing resin 16 may enter the hollow portion 26 via this gap. There is. The hollow portion 26 functions as a layer for preventing heat generated from the first circuit element 22 from being conducted to the second circuit element 24. Therefore, when the hollow portion 26 is filled with the second sealing resin 16, the heat generated from the first circuit element 22 through the filled second sealing resin 16 is generated by the second circuit element 24. There is a risk that the operation of the second circuit element 24 having a low operating temperature may become unstable.

  However, in this embodiment, as shown in FIG. 8B and FIG. 8C, the bonding material 17 is filled in each through-hole 15 of the second circuit board 20. This prevents leakage of the second sealing resin 16 into the hollow portion 26 via the through hole 15.

  Through the above steps, the hybrid integrated circuit device 10 whose structure is shown in FIG. 1 is manufactured.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the hybrid integrated circuit device which is one Example of the circuit device of this invention, (A) is sectional drawing, (B) and (C) are perspective views. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the hybrid integrated circuit device which is one Example of the circuit device of this invention, (A) is a perspective view, (B) is sectional drawing. It is sectional drawing which shows a part of hybrid integrated circuit device which is one Example of the circuit device of this invention. It is sectional drawing which shows the hybrid integrated circuit device which is one Example of the circuit device of this invention. It is a block diagram which shows the circuit integrated in the hybrid integrated circuit device which is one Example of the circuit device of this invention. (A) is a figure which shows the outdoor unit in which the hybrid integrated circuit device which is one Example of the circuit device of this invention was integrated, (B) is sectional drawing of the location where a hybrid integrated circuit device is attached. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the manufacturing method of the hybrid integrated circuit device which is one Example of the circuit device of this invention, (A) is sectional drawing, (B) is sectional drawing. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the manufacturing method of the hybrid integrated circuit device which is one Example of the circuit device of this invention, (A) is sectional drawing, (B) and (C) are perspective views. It is sectional drawing which shows the manufacturing method of the hybrid integrated circuit device which is one Example of the circuit device of this invention. It is sectional drawing which shows the hybrid integrated circuit device of background art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hybrid integrated circuit device 12 Case material 13 Exposed part 14 1st sealing resin 15 Through-hole 16 2nd sealing resin 17 Bonding material 18 1st circuit board 20 2nd circuit board 21 2nd conductive pattern 21A Pad 21B Wiring 22 1st 1 circuit element 24 second circuit element 26 hollow portion 28 lead 28A first lead 28B second lead 30 lead 32 mounting substrate 34 insulating substrate 36 insulating layer 38 first conductive pattern 38A pad 40 insulating layer 41 rectifier circuit 42 metal wire 43 smooth Circuit 44 Driver IC
45 Switching circuit 46 Motor 48 Outdoor unit 50 Housing 52 Compressor 54 Condenser 56 Fan 58 Heat sink 60 Mounting board 62 Nozzle

Claims (4)

Case material,
A first circuit board incorporated in the case material and having a first conductive pattern formed on a surface thereof;
A second circuit board having a second conductive pattern formed on the surface thereof and being incorporated in the case material so as to overlap with the first circuit board;
A first circuit element mounted on the first circuit board and electrically connected to the first conductive pattern;
A second circuit element mounted on the second circuit board and electrically connected to the second conductive pattern;
A sealing resin formed on the surface of the second circuit board so that the second circuit element is sealed;
A lead having one end connected to the first conductive pattern on the surface of the first circuit board and penetrating through a through-hole provided in the second circuit board, the other end being led out;
A hollow portion surrounded by the first circuit board, the second circuit board and the case material ,
The lead includes a first lead electrically connected to the second circuit element mounted on the upper surface of the second circuit board, and an electrical connection between the second circuit element mounted on the second circuit board. A second lead that is not connected
A circuit device characterized in that the gap between the first lead and the through hole of the second circuit board is filled with solder, and the gap between the second lead and the through hole is also filled with solder. .   The circuit device according to claim 1, wherein a pad made of the second conductive pattern is provided in a peripheral portion of the through hole of the second circuit board. A step of incorporating, into a case material, a first circuit board in which a first conductive pattern and a first circuit element are incorporated on a surface, and a lead is fixed to a pad made of the first conductive pattern;
A second circuit board having a through hole formed with the second conductive pattern and the second circuit element is incorporated in the surface, seen write set in the case member by penetrating the lead into the through-hole, the first circuit board Forming a hollow portion surrounded by the second circuit board and the case material ;
Forming a sealing resin on a surface of the second circuit board so as to cover the second conductive pattern and the second circuit element,
The lead includes a first lead electrically connected to the second circuit element mounted on the upper surface of the second circuit board, and an electrical connection between the second circuit element mounted on the second circuit board. A second lead that is not connected
A method of manufacturing a circuit device, wherein a bonding material is applied to both a through hole through which the first lead penetrates and a through hole through which the second lead penetrates to close the through hole. 4. The circuit according to claim 3 , wherein in the step of forming the sealing resin, the sealing resin is cured after being applied to the surface of the second circuit board in a liquid or semi-solid state. Device manufacturing method.

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