JP5308108B2 - Circuit device manufacturing method - Google Patents

Description

  The present invention relates to a method for manufacturing a circuit device, and more particularly, to a method for manufacturing a circuit device that is resin-sealed including the lower surface of a relatively large circuit board.

  As a method for sealing a circuit board in which a hybrid integrated circuit including transistors and chip elements is incorporated on the upper surface, there are a sealing method using a case material and a resin sealing method using a resin.

  In the case of using the case material, the hybrid integrated circuit formed on the upper surface of the circuit board is accommodated in the hollow part of the case material by fitting the lid-like case material provided with the hollow part to the circuit board.

  When resin sealing is employed, the hybrid integrated circuit formed on the upper surface of the circuit board is covered by injection molding using a mold. With reference to FIG. 6A, the structure of the hybrid integrated circuit device 100 sealed with resin will be described. In the hybrid integrated circuit 100, first, the upper surface of the circuit board 101 made of a metal such as aluminum is entirely covered with the insulating layer 102. A circuit element is connected to the conductive pattern 103 formed on the upper surface of the insulating layer 102 to constitute a predetermined hybrid integrated circuit. As elements disposed on the upper surface of the circuit board 101, a semiconductor element 105A and a chip element 105B connected by a thin metal wire 107 are illustrated. A lead 104 is fixed to the pad-like conductive pattern 103 at the end of the circuit board 101.

  The sealing resin 106 is a thermoplastic resin, and covers the upper surface, side surface, and lower surface of the circuit board 101. Here, in order to release heat generated from the circuit elements formed on the upper surface of the circuit board 101 to the outside through the circuit board 101, a sealing resin 106 that covers the lower surface of the circuit board 101 is used. Thinning is effective. However, if the thickness of the sealing resin 106 that covers the lower surface of the circuit board 101 is set to be as thin as, for example, about 0.5 mm, there arises a problem that the lower surface of the circuit board 101 is not partially covered with the sealing resin 106. This is because the gap between the lower surface of the circuit board 101 and the lower surface of the inner wall of the mold is narrowed in the step of injection molding the sealing resin 106 using a mold, and the sealing resin does not sufficiently reach the gap. Because.

A method for avoiding this problem will be described with reference to FIG. 6B (Patent Document 1 below). Here, the injection molding is performed with the support member 110 supporting the circuit board 101 from the lower surface. Specifically, the support member 101 is made of a thermoplastic resin, and the inner surface has a size that comes into contact with the lower surface and part of the side surface of the circuit board 101. Further, the outer surface of the support member 101 is in contact with the inner wall lower surface and side surfaces of the mold 112. Therefore, when the circuit board 101 supported by the support member 110 is stored in the cavity 114 of the mold 112, the support member 110 is positioned in the gap between the lower surface of the circuit board 101 and the lower surface of the inner wall of the mold 112. In this state, the circuit board 101 is resin-sealed by injecting a thermoplastic resin into the cavity 114. According to this method, since the support member 110 is located in the gap between the lower surface of the circuit board 101 and the lower surface of the inner wall of the mold 112, it is not necessary to inject liquid thermosetting resin into the gap. Generation of voids due to the lower surface of 101 not being partially covered is prevented. In addition, a potting resin 120 is formed on the upper surface of the circuit board 101 so as to cover the circuit elements in order to protect the fine metal wires and the like from the injection pressure during resin sealing.
Japanese Patent No. 3316449

  As a method for forming a sealing resin using a mold, there is a transfer mold in addition to the above-described injection mold. In this transfer mold, the upper surface, side surfaces and side surfaces of the circuit board 101 are formed by a thermosetting resin such as an epoxy resin. The lower surface is covered. In recent years, transfer molds are more frequently used than injection molds. The reason is that the transfer mold performs the resin sealing at a low temperature and a low pressure rather than the injection mold, and therefore has less adverse effect on circuit elements such as semiconductor elements.

  The transfer mold is also resin-sealed using a mold 112 as shown in FIG. Therefore, if the sealing resin that covers the lower surface of the circuit board 101 is made thinner, the gap between the inner wall lower surface of the mold 112 and the lower surface of the circuit board 101 may not be filled. The technique described in Patent Document 1 described above is for resin-sealing the circuit board 101 by an injection mold using a thermoplastic resin such as PPS (polyphenylene sulfide). Therefore, the thermoplastic resin used in the injection mold and the thermosetting resin used in the transfer mold are greatly different in nature, so that the technique described in Patent Document 1 relating to the injection mold can be applied to the transfer mold. Have difficulty.

  The present invention has been made in view of the above-described problems. The circuit board is integrally sealed with a sealing resin made of a thermosetting resin, and the lower surface of the circuit board is thinly covered with the sealing resin. Another object of the present invention is to provide a method for manufacturing a circuit device.

The method of manufacturing a circuit device according to the present invention includes a step of incorporating a hybrid integrated circuit comprising a conductive pattern and a circuit element on the upper surface of a circuit board, and housing the circuit board in a cavity of a mold, and sealing resin in the cavity. Sealing the upper surface, the side surface, and the lower surface of the circuit board with a sealing resin containing a thermosetting resin, and in the sealing step, the resin containing the thermosetting resin In the step of interposing the sheet between the circuit board and the lower surface of the inner wall of the mold, covering the lower surface of the circuit board with the molten resin sheet, and sealing, the opposite side of the circuit board The resin sheet is fixed in a state of being pressed against the lower surface of the circuit board by sandwiching the lead led out from the side with the mold, and is composed of the molten resin sheet Thickness lower surface of the circuit board is covered by a sealing resin, characterized in that thinner than the resin sheet.

  According to the present invention, transfer molding is performed in a state where a thin resin sheet containing a thermosetting resin is interposed in the gap between the lower surface of the circuit board and the lower surface of the inner wall of the mold. Therefore, the gap between the lower surface of the circuit board and the lower surface of the inner wall of the mold is filled with the molten and heat-cured resin sheet, so that the lower surface of the circuit board can be thinly covered with the heat-cured resin sheet. .

  Furthermore, since the present invention does not change the shape of the mold used for the mold, the existing mold can be used as it is, so that the cost increase by adopting the present invention is small.

  With reference to FIG. 1, the structure of the hybrid integrated circuit device 10 manufactured by the method for manufacturing a circuit device of the present invention will be described. 1A is a perspective view of the hybrid integrated circuit device 10, FIG. 1B is a sectional view taken along line XX ′ of FIG. 1A, and FIG. It is sectional drawing for demonstrating a structure.

  1A and 1B, in the hybrid integrated circuit device 10, a hybrid integrated circuit including a conductive pattern 16 and circuit elements is constructed on the upper surface of the circuit board 12, and is connected to this circuit. The lead 17 is led out to the outside. Furthermore, the hybrid integrated circuit constructed on the upper surface of the circuit board 12 and the upper surface, side surface and lower surface of the circuit board 12 are integrally covered with a sealing resin 14 made of a thermosetting resin.

  The circuit board 12 is a board made of a metal such as aluminum or copper. When aluminum is employed as the material of the circuit board 12, the upper and lower surfaces of the circuit board 12 are covered with an anodized film (alumite film). The specific size of the circuit board 12 is, for example, about vertical × horizontal × thickness = 61 mm × 42.5 mm × 1.5 mm. Here, a material other than metal may be employed as the material of the circuit board 12, and for example, ceramic or resin material may be employed as the material of the circuit board 12.

  Here, the side surface of the circuit board 12 is a surface perpendicular to the upper surface, but may be an inclined surface inclined with respect to the upper surface. When the side surface of the circuit board 12 is an inclined surface, a first inclined surface that is continuously inclined downward from the upper surface of the circuit board and a second inclined surface that is continuously inclined upward from the lower surface of the circuit board are provided. .

  The insulating layer 18 is formed so as to cover the entire surface of the circuit board 12. The insulating layer 18 is made of an epoxy resin highly filled with a filler. Since the thermal resistance of the insulating layer 18 is reduced by filling the filler, the heat generated from the built-in circuit element is favorably conducted to the circuit board 12 via the insulating layer 18.

  The conductive pattern 16 is made of a metal film such as copper having a thickness of about 50 μm, and is formed on the surface of the insulating layer 18 so as to realize a predetermined electric circuit. A pad made of the conductive pattern 16 is formed on the side where the lead 17 is led out.

  The circuit elements of the semiconductor element 20A and the chip element 20B are fixed to predetermined portions of the conductive pattern 16 through a bonding material such as solder. As the semiconductor element 20A, a transistor, an LSI chip, a diode, or the like is employed. Here, the semiconductor element 20 </ b> A and the conductive pattern 16 are connected via a fine metal wire 22. A chip resistor, a chip capacitor, or the like is employed as the chip element 20B. The electrodes at both ends of the chip element 20B are fixed to the conductive pattern 16 via a bonding material such as solder. Furthermore, a resin-sealed package or the like can be fixed to the conductive pattern 16 as a circuit element.

  As a bonding material for bonding circuit elements, solder, conductive paste, or the like is employed. Here, as the solder, lead eutectic solder or lead-free solder can be used. Furthermore, as the solder to be employed, high-temperature solder having a melting point higher than the temperature (for example, 180 ° C.) when the sealing resin 14 is formed is employed. As the conductive paste, Ag paste, Cu paste or the like is employed.

  The lead 17 is fixed to a pad provided in the peripheral portion of the circuit board 12 and functions as an external connection terminal through which an input signal and an output signal pass. Referring to FIG. 1B, a large number of leads 17 are provided along two opposing sides of the circuit board 12. Here, the lead 17 can be derived from four sides of the circuit board 12 or can be derived from one side.

  The sealing resin 14 is formed by transfer molding using a thermosetting resin. In FIG. 1B, the conductive pattern 16, the semiconductor element 20 </ b> A, the chip element 20 </ b> B, and the metal thin wire 22 are sealed with the sealing resin 14. The upper surface, side surfaces, and lower surface of the circuit board 12 are covered with the sealing resin 14. As the thermosetting resin constituting the sealing resin 14, epoxy resin, orthocresol novolak biphenyl, dicyclopentadiene, or the like is employed. Further, a filler is mixed in the sealing resin 14 for the purpose of reducing thermal resistance or the like. For example, the ratio of the filler mixed in the sealing resin 14 is 70% by weight or more and 90% by weight or less. And as a kind of filler, although the mixture of crystalline silica and crushed silica is adopted, fused silica, alumina, or silicon nitride may be adopted. Furthermore, the average particle diameter of the filler to be mixed is, for example, 20 μm or more and 30 μm or less.

  The sealing resin 14 will be further described with reference to FIG. The sealing resin 14 includes a first sealing resin 14A and a second sealing resin 14B. On the paper surface, the boundary between the first sealing resin 14A and the second sealing resin 14B is drawn, but both are integrated in an actual circuit device. As described in detail below, the first sealing resin 14A is formed by injecting a liquid resin into the cavity of the mold, and the second sealing resin 14B melts the resin sheet disposed on the lower surface of the circuit board 12. Is formed. The thickness T1 of the second sealing resin 14B that covers the lower surface of the circuit board 12 is, for example, 0.1 mm or more and 0.3 mm or less and is very thin. Since the thin second sealing resin 14B has a small thermal resistance, the heat released from the circuit element such as a semiconductor element is favorably released to the outside through the circuit board 12 and the second sealing resin 14B.

  In the present embodiment, the filler contained in the second sealing resin 14B is in a state of being more uniformly dispersed than the filler contained in the first sealing resin 14A. Specifically, the first sealing resin 14A is formed by injecting a liquid resin into the mold cavity. Accordingly, in the region where the flow of the liquid thermosetting resin is blocked, the filler stays and becomes relatively dense. For example, in the region A1 where the chip element 20B and the semiconductor element 20A are disposed, the flow of the liquid sealing resin is blocked by these elements, and the filler is in a dense state. On the other hand, in the area A2 where circuit elements such as semiconductor elements are not arranged, the flow of the sealing resin is good, and therefore the filler is arranged relatively sparser than the area A1.

  On the other hand, the second sealing resin 14B that covers the lower surface of the circuit board 12 is not formed by injection molding, but is formed by melting and heat-curing a resin sheet disposed on the lower surface of the circuit board 12. The Accordingly, the second sealing resin 14B basically does not flow in the resin sealing step, and therefore the filler is filled relatively uniformly over the entire area of the second sealing resin 14B. As a result, the thermal resistance of the second sealing resin 14B is uniform over the entire area, so that heat dissipation from the lower surface of the circuit board 12 is improved overall.

  Referring to FIG. 1C, the entire lower surface of the circuit board 12 and a part of the lower part of the side surface are covered with the second sealing resin 14B, but only the lower surface of the circuit board 12 is the second sealing resin 14B. The side surface and the upper surface of the circuit board 12 may be covered with the first sealing resin 14A. Furthermore, the vicinity of the center portion of the lower surface of the circuit board 12 may be covered with the second sealing resin 14B, and the peripheral portions of the upper surface, the side surface, and the lower surface of the circuit board 12 may be covered with the first sealing resin 14A.

  A method of manufacturing the hybrid integrated circuit device having the above configuration will be described with reference to FIGS.

  With reference to FIG. 2, first, the circuit board 12 in which the hybrid integrated circuit is incorporated on the upper surface is accommodated in the cavity 36 of the mold 30. 2A is a plan view showing this step, FIG. 2B is a cross-sectional view taken along line BB ′ of FIG. 2A, and FIG. 2C is FIG. Is a cross-sectional view taken along the line CC ′ of FIG.

  2A and 2B, a conductive pattern 16 having a predetermined shape is formed by etching on the upper surface of a rectangular circuit board 12 made of a metal such as aluminum. Then, a hybrid integrated circuit is formed by fixing the semiconductor element 20 </ b> A and the chip element 20 </ b> B at predetermined positions of the conductive pattern 16. Further, as shown in FIG. 2A, a plurality of leads 17 are fixed to the pad-like conductive pattern along the upper and lower sides of the circuit board 12.

  Referring to FIG. 2B, here, after the resin sheet 42 is placed on the lower mold 34, the circuit board 12 is placed on the upper surface of the resin sheet 42. The circuit board 12 is accommodated in the cavity 36 by bringing the upper mold 32 and the lower mold 34 into contact with each other. Further, the leads 17 led out from both sides of the circuit board 12 are sandwiched and fixed between the upper mold 32 and the lower mold 34. In this manner, the leads 17 are held between the upper and lower molds, so that the vertical and horizontal positions of the circuit board 12 in the cavity 36 are fixed. In the initial stage of this process, the resin sheet 42 is in a solid state in which a granular thermosetting resin is pressed. The mold 30 is equipped with a heater (not shown), and the mold 30 is heated to a temperature (for example, 170 ° C. or higher) at which the resin sheet 42 is melted and heat-cured. The heating of the mold 30 may be started before the resin sheet 42 is placed, or may be started after the resin sheet 42 is placed.

  With reference to FIG. 2 (A), the structure of the metal mold | die 30 is demonstrated. The mold 30 has a configuration in which a plurality of pods communicate with a cavity 36 via a runner 38. Here, three pods 40 </ b> A, 40 </ b> B, 40 </ b> C communicate with one cavity 36 in series via a runner 38. The pods 40A, 40B, and 40C are spaces in which pellets made of a columnar thermosetting resin are stored. The runner 38 is a path through which the liquid sealing resin in which the pellets are melted is transported from the pod to the gate 44 of the cavity 36. Two air vents 46 are provided on the side wall of the cavity 36 facing the gate 44 which is an inlet for the sealing resin. The air vent 46 is a path for releasing the air in the cavity 36 to the outside when the sealing resin is injected from the gate 44 into the cavity 36.

  Referring to FIG. 2C, a pod 40A is provided by hollowing a part of the lower mold 34, and this configuration is the same for the pods 40B and 40C. Here, the pod 40 </ b> A and the like may be provided in the upper mold 32.

  Referring to FIG. 3, next, the resin sheet 42 is melted, and the lower surface of the circuit board 12 is thinly covered with a sealing resin. FIG. 3A is a cross-sectional view showing this process, FIG. 3B is an enlarged cross-sectional view showing a state before the resin sheet 42 is melted, and FIG. 3C is a view when the resin sheet 42 is melted. It is an expanded sectional view showing a back state.

  Here, the resin sheet 42 that covers the lower surface of the circuit board 12 will be described. The resin sheet 42 forms part of the sealing resin that covers the circuit board 12 by being melted and heat-cured. Specifically, the resin sheet 42 is pressure-molded into a sheet shape having a predetermined shape by using a powdery thermosetting resin to which a filler, a curing agent, or the like is added. The composition of the resin sheet 42 may be the same as or different from the sealing resin injected into the mold cavity 36. The specific composition of the resin sheet 42 is the same as that of the sealing resin described above, and is formed by granulating a thermosetting resin to which a filler, a curing agent, or the like is added. Here, the thermosetting resin is granular with a diameter of 1 mm or less.

  In addition, since the resin sheet 42 is pressure-molded at a normal temperature at an extremely high pressure, the filling rate (volume ratio occupied by components such as resin powder with respect to the entire resin sheet 42) is about 99%. Higher than the tablet described. Therefore, since the air contained in the resin sheet 42 is very small, generation of voids in the sealing resin that covers the resin sheet 42 is suppressed.

  Referring to FIG. 3B, the thickness T2 of the resin sheet 42 is the thickness of the sealing resin that covers the lower surface of the circuit board 12 in the manufactured hybrid integrated circuit device 10 (shown in FIG. 1C). It is formed thicker than T1). Specifically, when the thickness T1 of the sealing resin shown in FIG. 1C is 0.1 mm to 0.3 mm, the thickness T2 of the resin sheet 42 is set to 0.5 mm to 0.6 mm. Is done. On the other hand, as described above, the position of the circuit board 12 inside the cavity 36 is fixed by holding the leads 17 by the mold. Accordingly, the shape and position of the lead 17 are set such that the distance between the lower surface of the circuit board 12 and the upper surface of the inner wall of the lower mold 34 is T1 (see FIG. 1C). For this reason, when the resin sheet 42 and the circuit board 12 are placed on the lower mold 34 so as to overlap each other and the lead 17 is clamped by the mold 30, the lead 17 is elastically deformed by a stress that pushes and bends downward from above. As a result, the resin sheet 42 is pressed against and fixed to the lower mold 34 by the lower surface of the circuit board 12. In this figure, the state of the lead 17 that is elastically deformed by being held by the mold is shown.

  Since the mold 30 is heated as described above, the resin sheet 42 is melted and softened over time, and the lower surface of the circuit board 12 is covered with the liquid or semi-solid resin sheet 42.

  Further, referring to FIG. 3C, since the lead 17 is elastically deformed and held between the molds as described above, if the resin sheet 42 is softened and loses its supporting force, the lead 17 The shape returns to its original shape, and the circuit board 12 sinks downward. Along with the sinking of the circuit board 12, a part of the softened resin sheet 42 moves from the lower side to the side of the circuit board 12 to cover the vicinity of the lower end of the side surface of the circuit board 12. Thus, the thickness T3 of the resin sheet 42 covering the lower surface of the circuit board 12 that has been sunk is, for example, not less than 0.1 mm and not more than 0.3 mm, and is equal to the thickness T1 of the sealing resin shown in FIG. It is.

  3A, the planar size of the resin sheet 42 is larger than that of the circuit board 12, and the peripheral portion of the resin sheet 42 protrudes from the circuit board 12 to the side. In this way, the resin sheet 42 is formed to be larger than the circuit board 12 in a plan view so that the lower surface of the circuit board 12 is entirely covered with the molten resin sheet 42 and the side face of the circuit board 12 is also covered. Is done.

  Here, the planar size of the resin sheet 42 may be equal to the resin sheet 42 or slightly smaller than the resin sheet 42. When the resin sheet 42 is smaller than the circuit board 12, the vicinity of the center portion of the circuit board 12 is covered with the resin sheet 42, and the lower surface of the circuit board 12 is separated from the lower mold 34. It is covered with the injected resin.

  Next, referring to FIG. 4A, a sealing resin is injected into the cavity 36. Specifically, the tablet 48 is put into the pod 40 </ b> A provided in the lower mold 34 and heated and melted, and then the tablet 48 is pressurized by the plunger 50. The tablet 48 has the same composition as the resin sheet 42 described above, and is obtained by pressure-molding a powdery thermosetting resin mixed with additives such as a filler into a cylindrical shape. As described above, since the mold is heated to about 170 ° C. or more, when the tablet 48 is put into the pod 40A, the tablet 48 is gradually melted. The sealing resin that has been melted into a liquid or semi-solid state flows through the runner 38 and passes through the gate 44, and then is supplied to the cavity 36. In the following description, the sealing resin supplied from the gate 44 is referred to as a first sealing resin 14A, and the sealing resin composed of the molten resin sheet 42 is referred to as a second sealing resin 14B.

  Further, as shown in FIG. 2A, the mold is provided with a plurality of pods 40A, 40B, and 40C. A tablet 48 is inserted into all the pods at the same time by the plunger 50. Pressurized. Then, the first sealing resin 14 </ b> A is supplied to the cavity 36 from the pods 40 </ b> A, 40 </ b> B, 40 </ b> C via the runner 38. As the first sealing resin 14 </ b> A is injected from the gate 44, the air inside the cavity 36 is discharged from the air vent 46 to the outside. Further, the conductive pattern and the circuit element arranged on the upper surface of the circuit board 12 are covered with the first sealing resin 14A.

  With reference to FIG. 4B, the injected liquid first sealing resin 14 </ b> A fills the cavity 36. Here, since the temperature of the mold is higher than the temperature at which the first sealing resin 14A is heated and cured, the first sealing resin 14A filled in the cavity 36 is polymerized and cured over time. To do. As shown in the figure, when the lower surface of the circuit board 12 and the lower part of the side surface are covered with the second sealing resin 14B made of the resin sheet 42, the upper surface and the upper part of the side surface of the circuit board 12 are the second sealing resin. 14B. On the other hand, when only the lower surface of the circuit board 12 is covered with the second sealing resin 14B, the upper surface and side surfaces of the circuit board 12 are entirely covered with the first sealing resin 14A. In addition, when only the vicinity of the center portion of the circuit board 12 is partially covered with the second sealing resin 14B, the peripheral portions of the upper surface, the side surface, and the lower surface of the circuit board 12 are covered with the first sealing resin 14A. .

  When both the first sealing resin 14A and the second sealing resin 14B are sufficiently polymerized and heated and cured by heating with the mold, the upper mold 32 and the lower mold 34 are separated from each other, and a molded product is obtained. Take out the hybrid integrated circuit device. Thereafter, the portion of the sealing resin 14 filled in the air vent 46 and the runner 38 is separated from the main body of the sealing resin 14.

  Referring to FIG. 4B, the boundary between the first sealing resin 14A and the second sealing resin is shown. However, since the second sealing resin 14B filled in the lower surface of the circuit board 12 and the first sealing resin 14A injected from the gate 44 are mixed in a liquid or semi-solid state, both are integrated. Formed. Here, the time required for the first sealing resin 14A and the second sealing resin 14B to be cured after being melted is approximately 10 seconds to 20 seconds.

  In this step, the second sealing resin 14B in which the resin sheet 42 is melted is heat-cured before the first sealing resin 14A injected from the gate 44. By doing in this way, pressure is applied to the boundary portion between the first sealing resin 14A and the second sealing resin 14B due to the curing shrinkage of the first sealing resin 14A covering most of the circuit board 12, The moisture resistance of this part can be ensured. On the other hand, if the second sealing resin 14B is cured and contracted after the first sealing resin 14A, cracks are generated in the boundary portion due to the curing contraction acting on the second sealing resin 14B, and moisture resistance is improved. There is a risk of deterioration.

  As a method of curing the second sealing resin 14B before the first sealing resin 14A, there are a method of adjusting the time for heating these resins and a method of adjusting the composition of the resin. In the above-described embodiment, the resin sheet 42 to be the second sealing resin 14B is first heated inside the cavity 36, and then the tablet 48 to be the first sealing resin 14A is put into the pod 40A. Yes. When adjusting the composition of the resin, a thermosetting resin included in the resin sheet 42 is used that has a shorter time required for heat curing than the thermosetting resin included in the tablet 48. In this case, the timing when the resin sheet 42 and the tablet 48 start to be heated may be simultaneously performed.

  With reference to FIG. 5, another method for resin-sealing the circuit board 12 will be described. Here, a method of resin-sealing a circuit device to which the leads 17 are fixed only along the right side of the circuit board 12 will be described. Referring to FIG. 2, since lead 17 is fixed along the right side surface on the paper surface, lead 17 is held by mold 30 as described above with reference to FIG. Thus, it is difficult to fix the position of the circuit board 12. Here, a contact pin 52 is provided on the inner wall of the upper mold 32, and the position of the circuit board 12 is fixed by pressing the vicinity of the left end of the upper surface of the circuit board 12 downward with the contact pin 52. . The contact pin 52 may be fixed to the inner wall of the upper mold 32, or may be movable so as to move in the vertical direction. Furthermore, the resin sheet 42 placed below the circuit board 12 is also fixed by the pressing force of the leads 17 and the contact pins 52. The manufacturing method is the same as that shown in FIGS. 2 to 4 except for the method of fixing the circuit board 12.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the hybrid integrated circuit device manufactured by the manufacturing method of the circuit device of this invention, (A) is a perspective view, (B) and (C) are sectional drawings. It is a figure which shows the manufacturing method of the circuit apparatus of this invention, (A) is a top view, (B) and (C) are sectional drawings. It is a figure which shows the manufacturing method of the circuit apparatus of this invention, (A) is sectional drawing, (B) And (C) is expanded sectional drawing. It is a figure which shows the manufacturing method of the circuit apparatus of this invention, (A) And (B) is sectional drawing. It is sectional drawing which shows the manufacturing method of the circuit apparatus of this invention. It is a figure which shows the conventional hybrid integrated circuit device, (A) And (B) is sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Hybrid integrated circuit device 12 Circuit board 14 Sealing resin 14A First sealing resin 14B Second sealing resin 16 Conductive pattern 17 Lead 18 Insulating layer 20A Semiconductor element 20B Chip element 22 Metal fine wire 30 Mold 32 Upper mold 34 Below Mold 36 Cavity 38 Runner 40, 40A, 40B, 40C Pod 42 Resin sheet 44 Gate 46 Air vent 48 Tablet 50 Plunger 52 Contact pin

Claims (6)

Incorporating a hybrid integrated circuit comprising conductive patterns and circuit elements on the upper surface of the circuit board;
The circuit board is housed in a cavity of a mold, and a sealing resin is injected into the cavity, thereby sealing the upper surface, the side surface, and the lower surface of the circuit board with a sealing resin containing a thermosetting resin. A process,
In the sealing step, a resin sheet containing a thermosetting resin is interposed between the circuit board and the lower surface of the inner wall of the mold, and the lower surface of the circuit board is covered with the molten resin sheet,
By sandwiching the lead led out from the opposite side of the circuit board with the mold, the resin sheet is fixed in a pressed state on the lower surface of the circuit board,
A method of manufacturing a circuit device, wherein a thickness of a lower surface of the circuit board covered with a sealing resin made of the molten resin sheet is thinner than the resin sheet. In the sealing step, after melting the resin sheet, a liquid sealing resin is injected into the cavity from the gate of the mold,
The method for manufacturing a circuit device according to claim 1, wherein the resin sheet is heated and cured before the sealing resin to be injected.   The method for manufacturing a circuit device according to claim 1, wherein the resin sheet is formed by pressurizing the thermosetting resin of powder before being heat-cured.   4. The method of manufacturing a circuit device according to claim 1, wherein the resin injected into the cavity from the gate of the mold and the resin sheet have the same composition.   5. The circuit device according to claim 1, wherein a size of the resin sheet is formed larger than that of the circuit board, and an entire lower surface of the circuit board is covered with the resin sheet. Production method. The filler contained in the sealing resin that is made of the molten resin sheet and covers the lower surface of the circuit board is injected from the gate of the mold and is included in the sealing resin that covers the upper surface of the circuit board. 6. The method of manufacturing a circuit device according to claim 1, wherein the circuit device is more uniformly dispersed than the filler.

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