JPH105895A - Production of metal supporting plate of resin seal type electronic part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method to easily form a dovetail groove in order for raising the bonding power of a metal supporting plate of a resin seal type semi-conductor device and a resin sealing body. SOLUTION: A groove having a vertical wall is formed on one side main face 12 of a metal supporting plate 10 for supporting a semi-conductor element 29. A dovetail groove 15a is formed by pressing other side main face 24 of the metal supporting plate 10 with a pressing member, deforming the other side main face 24 to form a step part 27 and at the same time, deforming a pair of wall faces of the groove of one side main face 12 so as to incline. The resin sealing body 30 is installed so as to include the dovetail groove 15a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a metal support plate covered with a resin sealing body in an electronic device such as a resin sealing type semiconductor device.

[0002]

2. Description of the Related Art As a semiconductor device, as shown in FIG. 1, a semiconductor element 2 is fixed on a metal support plate 1 having good heat dissipation and is covered with a resin encapsulant 3. The device is known. In this type of semiconductor device, a groove 4 may be formed on the surface of the metal support plate 1 in order to increase the bonding strength between the metal support plate 1 and the resin sealing body 3.

[0003]

By the way, in order to increase the bonding strength between the metal support plate 1 having the heat dissipation function and the support function and the resin sealing body 3, the groove 4 has a narrower entrance than the depth. It is desirable to form a groove. However, if the groove 4 having such a shape is formed by cutting, the cost is inevitably increased.

Accordingly, an object of the present invention is to provide a method capable of easily forming a groove having an entrance narrower than a depth in a metal support plate.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a circuit element, a metal support plate for supporting the circuit element, and a resin sealing body for covering the circuit element and the metal support plate. A method of manufacturing the metal support plate in a resin-sealed electronic component, comprising: a groove having a pair of opposed wall surfaces extending at right angles to one main surface of the metal support plate. A first step of forming one main surface of the metal support plate, and opposing a region on one side adjacent to the wall surface extending at a right angle of the one main surface of the metal support plate. The other main surface area of the metal support plate is pressed by a pressing member harder than the metal support plate to incline one of the pair of wall surfaces extending at a right angle, so that the width is wider at the back than the entrance. And a second step of obtaining a groove having Those involved in the production process of that metal support plate. In the present invention, the circuit element means various circuit components or circuit devices such as a semiconductor device, a resistor, a capacitor, an IC chip, and a circuit board device, and the electronic component is an active component used in an electric device. It means not only semiconductor components such as passive components, transistors and thyristors, but also all electric devices such as semiconductor circuit devices and integrated circuit devices, and also those having a pair of wall surfaces having steps such as grooves in FIG. It shall be.

[0006]

Since the groove formed in the first step of the present invention has a wall surface extending at right angles to the main surface of the metal support plate, it can be easily formed. The second step is a simple step of pressing with a pressing member, so that workability is good. Therefore, it is possible to easily and inexpensively manufacture a groove in which the width of the entrance is smaller than the width of the back.

[0007]

Next, a resin-sealed semiconductor device and a method of manufacturing the same according to an embodiment of the present invention will be described with reference to FIGS. First, a metal support plate 10 for use in a resin-sealed semiconductor device is prepared, and the metal support plate 10 is
1 and second pressing members 13 and 14, which can be called punching tools or stamping dies, are arranged on one main surface 12 of the metal support plate 10 and pressurized. The pressing members 13 and 14 are pressed against one main surface 12 of the metal support plate 10 by an apparatus (not shown). That is, the pressing members 13 and 14 corresponding to the target groove shape are driven into the metal support plate 10 by a method generally called punching,
Then remove. Thus, the first and second grooves 15 and 16 shown in FIG. The first and second grooves 15, 16 are formed by a pair of wall surfaces 17, 18, 19, 20 extending perpendicularly or perpendicular to the main surface 12.
And extends longitudinally from one end of the metal support plate 10 to the other end. The pressing member 13,
Since 14 is made of a material having higher hardness or rigidity than the metal support plate 10, when punching with the pressing members 13 and 14,
Plastic deformation occurs in the metal support plate 10, and grooves 15 and 16 are obtained.

Next, as shown in FIG. 4, a third pressing member 21 having a tip end surface having a width W2 larger than the width W1 of the second groove 16 is positioned on the second groove 16, and The pressing members 21 press the vicinity of both edges of the second groove 16. Thereby, as shown in FIG. 5, a concave portion 22 corresponding to the shape of the third pressing member 21 is formed, a groove 23 is formed on the bottom surface of the concave portion 22, and a two-stage groove 16a is formed.

Next, as shown in FIG. 6, a fourth pressing member (a punching member or a stamping member) 25 is arranged so as to face the other main surface 24 of the metal supporting plate 10, and the metal supporting plate 1
The receiving member 26 is disposed on one of the main surfaces 12 of the first supporting member 10, and the metal supporting plate 10 is supported by the receiving member 26. The fourth pressing member 25 is provided on the first main surface 12 of the metal support plate 10.
The groove 15 is positioned so as to face a region 12 a adjacent to one wall surface 17 of the groove 15. In FIG. 6, FIGS.
Although a fourth pressing member 25 for clarifying the relationship with FIG. 5 is arranged below the metal support plate 10, in FIG. The fourth pressing member 25 can be arranged on the upper side.

Next, the fourth main pressing member 10 arranged as shown in FIG.
Is pressed or stamped or punched. As a result, FIG.
As shown in (4), the fourth pressing member 25 cuts into the other main surface 24 of the metal support plate 10 to form a step 27, a thin portion 28 is formed in the metal support plate 10, and one of the first grooves 15 is formed. The upper side of the wall 17 is pushed inward, and the inclined wall 1
7a, and the width of the inlet is smaller than the width of the back.
7a results. That is, when the metal support plate 10 is pressed by the fourth pressing member 25, plastic deformation occurs, and the step 27
And a deformed groove 17a is generated. As shown in FIG. 8, two grooves 15a and 16a are provided on one main surface 12 of the metal support plate 10.
Extend from one edge to the other edge in a straight line parallel to each other.

When assembling a resin-encapsulated semiconductor device using the metal support plate 10 shown in FIGS. 7 and 8, a transistor chip, an IC chip, or the like is mounted on one main surface of the metal support plate 10 as shown in FIG. The semiconductor element 29 is fixed by a known die bonding method, and then the semiconductor element 29 is connected to an external lead (not shown) by an internal lead (not shown) by a known wire bonding method. The semiconductor element 29, the metal support plate 10, and the internal leads are covered with the resin sealing body 30. In addition, the resin sealing body 30
Is formed by a known transfer molding method or the like. At this time, not only one main surface 12 of the metal support plate 10 but also the other main surface 24 are covered with the resin sealing body 30 in order to enhance electrical insulation. Since the resin sealing body 30 also enters the grooves 15a and 16a and the step portion 27, the resin sealing body 30 and the metal support plate 10 are engaged with each other, and a large bonding strength is obtained.

As apparent from the above, the present embodiment has the following advantages. (B) Pressing members 13, 14, 21, 2 as male molds
Since the grooves 15a, 16a and the step 27 are formed by the pressing operation by 5, ie, punching or stamping, these can be easily formed. (B) Since the step 27 is provided in addition to the two grooves 15a and 16a, the resin sealing body 3 and the metal support plate 10 are firmly connected.

[0013]

[Modifications] The present invention is not limited to the above-described embodiment, and for example, the following modifications are possible. (1) First and second grooves 15, 16 as shown in FIG.
Is prepared, and then the other main surface 24 of the metal support plate 10 can be pressed by the wide pressing member 25a shown in FIG. In this case, the first groove 15 is deformed into a wedge-shaped groove 15b by expanding the right end of the pressing member 25a between the two grooves 15 and 16, and the second groove 15 has a deformation in which one wall surface is inclined. Groove 1
6b. (2) As shown in FIG. 11, a metal support plate 10 having first, second, and third grooves 31, 32, and 33 having a pair of wall surfaces having a step portion in the middle is prepared and pressed. Member 25b
The left end area of the lower main surface 24 of the metal support plate 10 is pressed by the above to form a step 27 as shown in FIG. 12, and the left side walls 34, 35 of the first groove 31 are inclined to reduce the width of the entrance. It can be narrower than the width at the back. In FIG. 11, the first, second, and third grooves 31, 32, and 33 are all two-step grooves, and the width a of the entrance of the recess formed in the back,
b> c are set so that a>b> c becomes narrower in this order. In FIG. 12, since three grooves 31, 32, 33 and one step 27 are provided, the bonding strength of the metal support plate 10 to the resin sealing body is extremely large. (3) In FIG. 7, the groove 16a may be omitted and only the groove 17a may be provided. (4) The present invention can be applied not only to semiconductor devices but also to similar electronic devices.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a conventional resin-encapsulated semiconductor device.

FIG. 2 is a sectional view showing an apparatus for forming a metal support plate and a groove used in a resin-sealed semiconductor device according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a state where a first-stage groove is formed in a metal support plate.

FIG. 4 is a cross-sectional view for explaining a method of deforming a second groove.

FIG. 5 is a sectional view showing a metal support plate in which a second groove is deformed.

FIG. 6 is a cross-sectional view for explaining a method of deforming a first groove.

FIG. 7 is a cross-sectional view showing a metal support plate in which a dovetail groove is formed.

FIG. 8 is a plan view of the metal support plate of FIG. 7;

FIG. 9 is a sectional view showing a completed resin-sealed semiconductor device.

FIG. 10 is a cross-sectional view illustrating a metal support plate and a pressing member according to a modification.

FIG. 11 is a sectional view showing a metal support plate and a pressing member according to another modification.

FIG. 12 is a sectional view showing a metal support plate in which the first groove of FIG. 11 is deformed.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Metal support plate 15a 1st groove 16a 2nd groove 29 Semiconductor element 30 Resin sealing body

Claims (1)

[Claims] 1. A metal support plate for a resin-sealed electronic component comprising: a circuit element; a metal support plate for supporting the circuit element; and a resin sealing body for covering the circuit element and the metal support plate. Forming a groove in one main surface of the metal support plate, the groove having a shape in which a pair of wall surfaces facing each other extend at right angles to one main surface of the metal support plate. And the other main surface area of the metal support plate facing the area on one side adjacent to the wall surface extending at a right angle to the one main surface of the metal support plate, A second step of inclining one of the pair of wall surfaces extending at a right angle by pressing with a pressing member harder than the support plate to obtain a groove having a width wider than the inlet. A method for producing a metal support plate, characterized by comprising: