JPS58191453A - Semiconductor device - Google Patents

Abstract

PURPOSE:To contrive to reduce inductance without increasing parasitic capacitance of the semiconductor device by a method wherein a metal tape to make electric contact between a metal electrode part on the upper surface of the active layer of a semiconductor pellet and a case is widened in proportion to approach the case. CONSTITUTION:The metal tape 7 is fusion welded to the metal electrode part 3 and the upper surface of the insulator part 5 of the case to make electric contact to the pellet consisting of a substrate layer 1, the active layer and the metal electrode part 3 on the upper surface of the active layer, and to the case consisting of a metal part 4 and the insulator part 5. By narrowing width of the metal tape 7 at the part to be fusion welded to the metal electrode part 3, projection of the crushed part of the metal tape 7 to the outside of the metal electrode part 3 is not generated when fusion welding is performed, and increase of parasitic capacitance according to a gap between the projecting part and the substrate layer 1 is dissolved, while because width of the metal tape 7 at the part other than the circumference of the metal electrode part 3 is widened, large reduction of inductance can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device having a wiring inductance component.

Semiconductor devices used at high frequencies have their own junction capacitance and IE string low resistance inductance.

It is necessary to reduce stray capacitance, parasitic resistance, case capacitance, etc. as much as possible, and various measures are being taken to achieve this. Among these, the <K inductance is the electrical contact between the metal electrode part of the pellet, which has an active layer on the substrate layer and a metal electrode part on the top surface of the active layer, and the case consisting of the metal part and the insulator part. It is mainly determined by the wiring part, such as metal wire or metal tape, used for the purpose. FIG. 1 shows a cross-sectional view of a conventional semiconductor device, showing a pellet having an active layer 2 on a substrate layer 1 and a metal electrode part 3 on the top surface of an active part 112, a metal part 4 and an insulator part. 5 (However, the contact surface of the insulator portion 5 with the metal portion 4 and the opposite surface thereof are normal.

A metal electrode part 3 and an insulator part 5 are connected to each other in order to make contact with the case (on which a metal film is formed by vapor deposition, etc.).
A metal wire of uniform thickness or a metal tape 6 of uniform width is fused to the upper surface. FIG. 2 shows a top view of the metal electrode part 3 and the top surface of the insulator part 5. In order to make electrical contact between the metal electrode part 3 and the upper surface of the insulator part 5, a metal of uniform thickness is fused to these parts. The wire frame was a metal tape 6 of uniform width. In order to reduce the inductance of the semiconductor device and improve the high frequency characteristics, the thickness, width, length, and thickness of the uniform wire tape 6 must be increased.

It needs to be wide, short, and thick. However, in semiconductor devices that are required to be used at high frequencies, the area of the metal electrode part 3 that reduces junction capacitance is very small, and the area of the metal electrode part 3 that is fused to the metal electrode part 3 is very small. The metal wire or uniform-width metal tape 6 may also be flattened during fusion, causing the width of the uniform-thickness metal wire or uniform-width metal tape 6 to widen and protrude to the outside of the metal electrode portion 3. In order to avoid an increase in the parasitic capacitance between the substrate layer 1 and the substrate layer 1, and to avoid contact with the peripheral substrate layer 1, it was necessary to make the thickness and width narrower. FIG. 3 shows that the fused portion of the uniform-thickness metal wire or uniform-width metal tape 6 is fused to the metal electrode portion 3 because the thickness and width are made thicker and wider over the whole to reduce inductance. This is a cross-sectional view showing how the metal electrode part 3 protrudes from the crushing K during fusion.
The figure shows its top view.

When using a conventional semiconductor element at a high frequency as described above, the area of the metal electrode part 30 becomes small in order to reduce the junction capacitance, and the area of the metal electrode part 30 becomes small, and the metal wire of uniform thickness or
The flattening of the uniform width metal tape 6 during welding causes the metal electrode portion 3 to
In order to prevent it from protruding from the % uniform thickness metal wire or uniform width metal tape 6, it is necessary to make the thickness and width of the uniform thickness metal wire thinner or narrower. Not only is it not possible to satisfy the demand for thickening or widening the thickness or width of the uniform width metal tape 6, but it is also impossible to make the thickness or width of the uniform width metal wire or the uniform width metal tape 6 thinner or narrower. If this happens, the inductance will be increased more than K, resulting in significant deterioration of the high frequency characteristics of the semiconductor device.

An object of the present invention is to provide a semiconductor device in which inductance can be reduced without increasing stray capacitance.

- FIG. 5 is a schematic diagram showing an embodiment of the inductance reducing semiconductor device according to the present invention, with a part of the insulator section 5 of the case omitted for explanation, and shows a substrate layer 1, an operating layer and an operating layer. A metal tape 7 is placed between the pellet consisting of the metal electrode section 3 on the upper surface of the layer and the case consisting of the metal section 4 and the insulator section 5 for electrical contact.
It is fused to the top. In the semiconductor device IIc used at high frequencies, the area of the metal electrode part 50 is very small, so the width of the metal tape 70 fused thereto is such that the crushing of the metal tape 70 at the time of fusion is outside the metal electrode part 3. protruding,
The stray capacitance between this protruding part and the substrate layer 1 has increased9, there is a need to narrow the protruding part and the substrate layer 1 to avoid welding, and there is a need to reduce inductance. It has a structure that satisfies both requirements and events. That is,
The width of the metal tape 70 is not uniform over the entire area; the width of the metal tape is narrow around the metal electrode portion 3 of the pellet, and the width is wide in other areas.

In this way, by narrowing the width of the metal tape 70 at the portion to be fused to the metal electrode part 3, the width of the metal tape 70 is reduced during fusion.
Since the collapsed portion does not protrude to the outside of the metal electrode portion 3, the increase in stray capacitance between the V% protruding portion and the substrate layer 1, and the problem of contact between the protruding portion and the substrate layer 1 are eliminated. 4, the width of the metal tape 70 in the part other than the complementary side of the metal electrode part 3 is rounded, and even if the area of the metal electrode part 30 becomes smaller, there is no increase in inductance as in conventional semiconductor devices; This will result in a significant reduction in The high frequency characteristics of the semiconductor device according to the present invention using the metal tape 7 having such a force structure are far superior to those of conventional semiconductor devices. The inductance value can be freely changed by keeping the width constant so that the crushed part during fusion does not protrude from the metal electrode part 3, and changing the width of the metal tape 70 in other parts. Therefore, by selecting an appropriate width of the metal tape 7 (mK) without changing the pellet or case, in other words, by changing only the inductance determined by the metal tape 7, the high frequency characteristics of the semiconductor element (for example, the resonant frequency) can be improved. etc.) can be freely adjusted according to the purpose of use. FIG. 6 Fi is a top view of FIG. 5 with a part of the insulator section 5 of the case omitted, and is shown without omitting a part of the insulator section 5;

7 to 9 each show other embodiments of the present invention;
In FIG. 8, a metal electrode part 3 of a pellet consisting of a substrate layer 1, an active layer, and a metal electrode part 3,
Insulator part 5 of the case consisting of metal part 4 and insulator part 5
The width or thickness of the metal tape or metal wire 70 to be fused to the upper surface portion is made narrower around the metal electrode portion 3 in order to prevent it from protruding from the metal electrode portion 3 due to the crushing K during fusion. In other parts, the top view of the semiconductor device is shown in which the width and thickness of the metal tape or metal wire 7 is gradually widened or thickened to reduce the inductance and still have an appropriate amount of inductance. This is what is shown.

Figure 9 shows the insulator section 5 of the case to reduce the case capacitance.
For a semiconductor device with a smaller substrate layer l
The width is narrow around the metal electrode part 3 of the pellet having the active layer and the metal electrode part 3.

This is a schematic diagram of an example in which a metal tape 7 having a wider width in other parts is used.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a conventional semiconductor device, Fig. 2 is a top view thereof, and Fig. 3 is a nine-dimensional structure fused to the metal electrode part of the pellet.
Figure 4 is a cross-sectional view of a conventional semiconductor device in which a width metal tape and a uniform-thickness metal wire are crushed during fusion, and the crushed portion protrudes from the metal electrode part. FIG. 5 is a schematic diagram of a semiconductor device according to an embodiment of the present invention.
For convenience, a part of the insulator part of the case is omitted. FIG. 6 is a top view of the semiconductor device of FIG. 5 in which the insulator portion of the case is omitted. 7 and 8 each show a top view of a semiconductor device according to another embodiment of the present invention, and FIG. 9 shows a schematic diagram of a semiconductor device according to still another embodiment of the present invention. 1...Low resistance semiconductor substrate (substrate layer)
2... Operating layer, 3... Metal electrode part, 4
...Metal part of the case, 5...Insulator part of the case (a metal film is formed on the surface opposite to the surface in contact with the metal part 4), 6... - Uniform width metal tape or uniform thickness metal wire 17...Metal tape or metal wire.

Claims (1)

[Claims] In a semiconductor device consisting of a semiconductor pellet and a case in which a solid pellet is mounted, the thickness or width of the metal wire or metal tape for making electrical contact between the metal electrode part on the upper surface of the active layer of the pellet and the case is determined. A semiconductor device characterized in that the semiconductor device becomes thicker or wider as it approaches the case.