JPS5844732A - Semiconductor device - Google Patents

Abstract

PURPOSE:To reduce the parasitic capacity of a semiconductor device by notching the surface of a metallic base at the parts opposed to the gate and drain electrodes of a semiconductor substrate. CONSTITUTION:The surface of a grounding metallic base 5 is notched at the parts opposed to gate and drain electrodes 3, 4 of a semiconductor substrate 100, thereby expanding a gap 53. Accordingly, the parasitic capacity can be reduced, thereby improving the high frequency characteristics. Excessive solder is absorbed to the notch 53, thereby preventing a shortcircuit with the gate electrode 3. A notch may be formed on the surface of the metallic base opposed to the source electrode 2 according to the disposition of the FET pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a semiconductor device, and particularly to a flip-chip microwave semiconductor device. Specifically, the present invention provides a structure that can improve the performance of a flip-chip type microwave semiconductor device.

Here, a Schottky barrier field effect transistor (referred to as 5BFET) will be explained as an example of a microwave semiconductor element.

FIG. 1 is a perspective view showing an example of a conventional flip-chip type 5BFET. As shown in FIG. 1, a flip-chip type 5BFET has a source electrode (2), a gate electrode 1ii (1), and a drain electrode (4) arranged on the main surface of a semiconductor substrate (1), and is a flip-chip type 5BFET. For chip bonding, source protruding electrodes (c) are provided on the source electrode (2), gate electrode (3) and drain electrode (4), respectively.
It has a structure including a gate protrusion electrode 01) and a drain protrusion electrode (2). Figure 2 shows such a 5BFET-
This is a cross-sectional view taken along line 1-1 in Figure 1 of the 5BFET shown in Figure 1 bonded to the pedestal by flip-step bonding on the metal base (6). It is. In Figure 2, '(6
) is a metal base, (6) is an insulator such as alumina ceramic, (7) is a metal line provided on ceramic, (8
) is a ceramic metallized film provided for bonding the ceramic (6) and the metal base (5).

FIG. 8 is a sectional view showing the state shown in FIG. 2 viewed from a different angle, that is, the state taken along the line 1--1 in FIG.

- In a conventional flip-chip type 5BFET such as Jin, the source electrode (2) is grounded to a metal base (5) which acts as a pedestal, as can be seen in Figure 8;
The surface of the metal base (6) and the drain electrode (
4). As a result, a parasitic capacitance is generated between the drain electrode and the grounded metal base (5), and as is well known, this increase in parasitic capacitance has the disadvantage of degrading the performance of the GIA8FET. are doing.

This invention has been made in view of the above points, and embodiments shown in the drawings will be described below.

Figure 4 shows a flip chip type 5 which is an embodiment of Jin's invention.
It is a sectional view showing a BFET. In the figure, (5) is a metal base, and this metal base (5) has a half surface and a notch in the part facing the gate electrode (3) and drain electrode (4) formed on the conductive base. It is formed.

Therefore, since the surface facing the ground metal base (5) is large, the parasitic capacitance is reduced compared to the conventional device. Therefore, performance, especially high frequency characteristics, can be improved compared to conventional devices.

Furthermore, when bonding the source projecting electrode (to the source projecting electrode) to the metal base (5) using solder, etc., excess solder, even if it flows, is absorbed into this notch, so that it may not be applied to other adjacent electrodes, i.e., the gate electrode. (3) Since short circuits with the above can be prevented, work efficiency is greatly improved.

In the above description, the source electrode (2) is grounded and a notch is provided on the surface of the metal base (5) in a portion facing the drain electrode (4) and gate electrode (3). is not limited to this, but 5BFET
Depending on the arrangement of the pattern, a notch may be provided on the surface of the metal base corresponding to the source electrode (2).

As explained above, according to the present invention, it is possible to improve the performance of a flip-chip type 5BFET, and it has a great practical advantage.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing the electrode arrangement of a conventional flip-chip type 5BFET, and Fig. #I2 is a cross-sectional view taken along the line 1-1 in Fig. FIG. 8 is a sectional view similarly taken along line 11, and FIG. 4 is a sectional view showing an embodiment of the apparatus of the present invention. In the figure, (1) is a semiconductor substrate, (2) is a source electrode, and (3) is a semiconductor substrate.
) represents the gate electrode, (4) represents the drain electrode, (2) represents the gate electrode, the source represents the protruding electrode, (2) represents the gate electrode, the source represents the drain protruding electrode, and - represents the notch according to the present invention. Further, (6) represents the metal base of the pedestal, (6) represents the ceramic portion, (7) represents the metal line, and (8) represents the metallized film. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Makoto Kuzuno - Figure 1 Figure 2

Claims (1)

[Claims] (a first electrode formed on the first surface of one main surface of the semiconductor substrate, a first protruding electrode provided on the first electrode, a second electrode formed on the second surface of one main surface of the semiconductor substrate) an electrode, a metal base to which a first electrode is connected via the first protruding electrode so that one principal surface of the semiconductor substrate faces each other, and a ζζ notch on the surface of the metal base in a portion facing the second electrode; A semiconductor device characterized in that a semiconductor device is provided with a section.