JP2539144Y2 - Semiconductor module - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor module obtained by mounting a power semiconductor chip and a control component for controlling the semiconductor chip on the same metal substrate and sealing the resin with a resin.

[0002]

2. Description of the Related Art Conventionally, as a semiconductor module, for example, one having a structure shown in a sectional view of FIG. 3 is known. FIG. 4 is a plan view showing the circuit board before the semiconductor module is attached to the case. In the drawing, reference numeral 1 denotes a metal substrate having an insulating layer (not shown) on the entire surface. A copper circuit 2 having a convex shape is bonded and soldered from a substantially central portion to one end of the metal substrate 1, and is applied to the other end. A concave printed wiring board 3 having a copper circuit pattern printed on an insulating plate is bonded to the insulating layer by an adhesive sheet or the like.

[0005] Then, cream solder is printed on required portions of the copper circuit 2 and the printed wiring board 3 of the metal substrate 1, and a power semiconductor chip 4 is provided on the copper circuit 2, and a surface mount component is provided on the printed wiring board 3. After mounting control parts 5 such as resistors, ICs, capacitors, etc., and mounting external lead-out terminals 6 at necessary places on the metal substrate 1, soldering all parts in a reflow furnace, By performing the connection 7, a circuit board as shown in FIG. 4 is obtained.

[0004] Next, the top and bottom edges of the circuit board are placed on the upper lid 1.
1a, the side wall 11b and the inner wall 11c are covered with a resin case 11 integrally molded, and the side wall 11b is adhered to the metal substrate 1 with an adhesive such as silicon rubber. At this time, the inner walls 11c, 11c provided at predetermined positions so as to surround the power semiconductor chip 4 and the control component 5 are also bonded on the metal substrate 1. Then, silicon rubber is filled into the inner walls 11c, 11c from the opening 11d provided in the upper lid 11a of the case 11, and the silicon rubber layer 12 is formed by heating and curing at 120 to 150 ° C. Next, an epoxy resin is filled from the opening 11d on the silicon rubber layer 12 and between the side wall 11b and the inner wall 11c, and is cured by heating at 120 to 150 ° C., so that the epoxy resin layer 13 After fixing, an epoxy resin layer 13 is formed on the silicon rubber layer 12 to obtain a semiconductor module as shown in FIG. Instead of attaching a copper circuit and a printed wiring board on which control components are surface-mounted in advance to the metal substrate having the insulating layer, a copper circuit is arranged on the metal substrate via an insulator, and a power semiconductor is placed on the copper circuit. Chips and control components may be placed and soldered.

[0005]

However, in order to obtain the semiconductor module as described above, conventionally, when an epoxy resin having a high viscosity is used to fill the silicon rubber layer 12 with an epoxy resin, the silicon Since the inner wall 11c surrounding the rubber layer 12 is slightly higher than the height of the silicon rubber layer 12 and its tip has a flat square shape, epoxy resin is applied on the silicon rubber layer 12 and between the inner wall and the side wall. There is a problem that it takes a very long time to flow into the fixing portion of the lead terminal 6.

[0006]

SUMMARY OF THE INVENTION In view of the above, this invention has been studied as a result of a study on a case in which a circuit board on which a power semiconductor chip and a control component are mounted and an external lead-out terminal is mounted is enclosed in a case and sealed with a resin. In addition, it has been found that the problem of resin sealing of a conventional semiconductor module can be solved by using a resin case including an upper lid having an opening, a side wall, and an inner wall, and forming a tip of the inner wall in a tapered shape outward. Things.

That is, the present invention mounts and fixes a power semiconductor chip and a control component on a copper circuit laminated on a metal substrate having an insulating layer or a metal substrate to which the insulating substrate is bonded,
Further, the circuit board obtained by attaching the other end of the terminal member whose one end is drawn out to the upper part of the case on the metal substrate is formed integrally with the upper lid, the side wall and the inner wall, and has an opening in the upper lid, and An object of the present invention is to provide a semiconductor module in which a tip of an inner wall is covered with a resin case having a tapered shape outward, and the inside of the case is sealed with a resin.

[0008]

According to the present invention, when a circuit board on which a power semiconductor chip and a control component are mounted is resin-sealed as described above, an upper lid having an opening, a side wall, and an inner wall are formed. Using a resin case formed in a tapered shape, silicon rubber is filled from the opening 11d of the upper lid 11a, and an epoxy resin for forming an epoxy resin layer is filled on the silicon rubber layer obtained by heat curing. At this time, even when an epoxy resin having a high viscosity is used, since the tip of the inner wall is formed to be tapered outward, an external lead-out terminal between the inner wall and the side wall along this tapered surface. The epoxy resin can be easily poured into the fixed portion in a short time.

[0009]

FIG. 1 shows an embodiment of the present invention in detail. In the drawing, the same reference numerals as those in the conventional example indicate the same parts. In FIG. 1, the resin case 11 has a case upper lid 11a, a side wall 11b, and an inner wall 11c integrally formed, has an opening 11d in the upper lid 11a, and a tip of the inner wall 11c is formed in an outward tapered shape 11e. The resin case 11 having such a structure is mounted with the power semiconductor chip 4 and the control component 5, the external lead-out terminal 6 is attached, and the connection 7 between the circuits is performed.
The side wall 11b is attached to the outer edge by bonding, and at the same time, the lower end of the inner wall 11c having a tapered outer end 11e is also bonded to the metal substrate 1. Then, the inner walls 11c, 1
Silicon rubber is filled into the power semiconductor chip 4 and the control component 5 in 1c through the opening 11d of the case upper lid 11a, and cured by heating to form a silicon rubber layer 12.

Next, an epoxy resin is poured from the opening 11d into the fixed portion of the external lead-out terminal 6 on the formed silicone rubber layer 12 and between the inner wall and the side wall, and is cured by heating to form the epoxy resin layer 13. The semiconductor module of the present invention is obtained. Even when the epoxy resin 13a having a high viscosity is poured into the above-mentioned silicon rubber layer and the fixing portion of the external lead-out terminal 6 between the inner wall and the side wall, FIG. As shown in the enlarged partial cross-sectional view, since the tip of the inner wall 11c of the resin case 11 has a tapered shape 11e outward, it can be easily poured particularly into the external drawer terminal fixing portion. The taper angle is suitably about 40 to 50 degrees.

[0011]

As described above, according to the present invention, the circuit board on which the power semiconductor chip and the control parts are mounted, the external lead-out terminals are attached, and the circuits are connected to each other are surrounded by a resin case and sealed with a resin. At the time of stopping, by using a resin case that is formed integrally with the upper lid, the side wall, and the inner wall, has an opening in the upper lid, and the tip of the inner wall is tapered outward, the resin sealing in the case is achieved. Can be performed in a short time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the semiconductor module of the present invention.

FIG. 2 is an enlarged partial cross-sectional view of the semiconductor module of the present invention.

FIG. 3 is a sectional view of a conventional semiconductor module.

FIG. 4 is a plan view of a circuit board constituting the semiconductor module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal substrate 2 Copper circuit 3 Printed wiring board 4 Power semiconductor chip 5 Control component 6 External lead-out terminal 11 Resin case 11a Top lid 11b Side wall 11c Inner wall 11d Opening 11e Tapered part 12 Silicon rubber layer 13 Epoxy resin layer

Claims (1)

(57) [Scope of request for utility model registration] 1. A power semiconductor chip and a control component are mounted and fixed on a metal substrate having an insulating layer or a copper circuit laminated on a metal substrate to which an insulating substrate is bonded, and one end is located outside the upper part of the case. A circuit board obtained by attaching the other end of the terminal member to be pulled out onto the metal substrate is formed by integrally molding the upper lid, the side wall and the inner wall, the upper lid has an opening, and the tip of the inner wall is tapered outward. A semiconductor module covered with a resin case exhibiting the above, and the inside of the case is resin-sealed.