JPS61100955A - Semiconductor device - Google Patents

Abstract

PURPOSE:To reduce output-waveform strain without easily using a filter, etc. by forming a conductor for grounding around an integrated circuit formed onto a semi-insulating semiconductor substrate, a pad for a terminal for an input and input/output signal lines. CONSTITUTION:A conductor 6 for grounding is arranged around bonding pads 1, 4 for input/output terminals to an integrated circuit 2 shaped onto a semi- insulating semiconductor substrate 3 and an input/output signal connecting line 5. Consequently, distances among the input/output terminal pads and the grounding conductor can be reduced remarkably, thus localizing the induction noise field of clock signals, which have been radiated within a range comparatively wider than chip size, near the clock input/output terminal pads. Likewise, a distance between the output terminal pad and the grounding conductor is also shortened, and the device is difficult to receive the induction noises of clock signals. Accordingly, the induction noises of clock signals in an output electrode can be minimized, thus easily improving the waveform strain of output signals.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a semiconductor device, and more particularly to an ultrahigh-speed logic circuit device formed on a semi-insulating semiconductor substrate and capable of easily reducing the n1 output waveform. technology P and its problems) Monolithic integrated circuits (I
C) La, is attracting attention especially in ultra-high-speed digital ICs because of its high speed t-M due to the high electron mobility of gallium arsenide. The use of GaAs monolithic integrated circuits (ICs) enables operation at multiple GHz, and is expected to play an extremely important role in the field of microwave communications. By the way, in the conventional GaAs ultra-high-speed logic IC, there is output waveform distortion in the output signal waveform due to interfering noise of the clock signal, and it is practically impossible to use an ultra-flat frequency divider for microwave communication in %. I have a dog problem.

FIG. 2 is a plan view of a conventional 1/2 frequency divider integrated circuit device. In Figure 1, 1 is a clock pad, area 2 within the broken line is a frequency divider circuit formed on a gallium arsenide substrate 3 by a conventional method, 4 is an output pad, and 5 is a frequency divider circuit. An output signal connection line connects the output pad 4 and the output pad 4.

If an ultra-high frequency clock signal is applied to the clock input pad 1 of the collector and (b) circuit device with such a configuration, the clock 16, the clock 16, and its feeder line will be used as radiation sources in the air and This noise radiates a noise signal inside the semi-insulating gallium arsenide substrate and appears as induced noise at output signal connection #5 and output pad 4. According to experiments conducted using the present invention, the above-mentioned phenomenon has actually been confirmed as noise having a frequency of tV equal to or equal to the signal in the output waveform even when the IC power supply voltage value is zero.

In this way, in the conventional 1/2 frequency divider IC, distortion occurs in the output waveform. Here is an example of monitoring the output waveform of the device at a certain frequency. In the same figure, 11 is the output frequency divided by 172 waveform, 1
2 is nine black as mentioned above.

It is caused by the induced noise. Therefore, the resulting output waveform becomes a highly distorted waveform shown by 13 as the sum of both. Furthermore, when the clock frequency changes, the clock induced noise voltage amplitude, the 1/2 frequency divided waveform 11, and the induced noise component 12 change. The actual output waveform 13 changes because both phases of the relationship change.
has the disadvantage that it changes depending on the clock frequency. For this reason, in the past, it was necessary to connect a filter for eliminating noise at the rear of the frequency divider IC in order to monitor the output waveform, which was extremely inconvenient in practice. Taking a frequency divider IC as an example, k is
Needless to say, the above drawbacks also exist in other ultrafast logic circuits using expanded gallium oxide.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a semiconductor device t including an integrated circuit which can improve the conventional problems and easily reduce output waveform distortion without using a filter or the like.

(Means to resolve the problem r'j!%) The present invention provides an integrated circuit formed on a semi-insulating semiconductor substrate, and bonding pads for input/output terminals and input/output signal connections to this integrated circuit. The semiconductor device is characterized in that grounding bodies are arranged on these circumferential curves.

(Example) Hereinafter, the present invention will be explained with reference to the drawings.

FIG. 1 is a plan view of an embodiment of the semiconductor device of the present invention. In the same figure, l is an input pad, 2 is a frequency divider circuit formed on a gallium arsenide base & 3 by a conventional method. part,
4 is an output pad, 5 is an output signal connector, 6 is an input/output cover,
In the semiconductor device having the structure of the present invention, the input/output terminals conventionally formed on the surface of the gallium arsenide substrate 3 are grounded conductor patterns arranged close to the terminals and the input/output signal connection lines. Compared to a radiation source formed by a pair of a pad and a ground conductor formed on the layer surface of the substrate 3, the distance between the input/output terminal pad and the ground conductor can be significantly reduced. Therefore, the conductive noise electric field of the clock signal, which conventionally was radiated over a relatively wide range compared to the chip size, is now localized near the input terminal pad, and is also radiated to the output terminal pad. Since the distance to the ground conductor is also reduced, interference noise of the clock signal2
◇ Therefore, compared to the conventional technology, the induced noise of the clock signal at the output I & L poles can be easily reduced, and the waveform of the output signal, which has been a problem in the past, can be reduced. ! can be easily modified. In the above embodiment, the frequency divider circuit is provided on a GaAs substrate, but the integrated circuit may be formed on other semi-insulating semi-integrated substrates. It is clear that it is also applicable.

(Effects of the Invention) As described above, according to the present invention, the distortion of the output waveform caused by the induced noise of the input signal can be easily removed, and therefore there is no need to use an external filter. All of the shortcomings of the prior art, such as changes in output waveform due to wave number, can be easily improved and minimized.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the present invention, Fig. 2 is a plan view of a conventional 1/2 frequency divider, and Fig. 3 is a 1/2 frequency divider of Fig. 2.
The output waveform monitor diagram of the 2 frequency divider is shown. 1...Input pad, 2...1/2 frequency divider circuit section, 3...Semi-insulating gallium arsenide substrate,
4... Output parad, 5... Output signal 1
! 2 wires, 6...Grounding ring. Rod! Figure $ 2 Figure 3 side

Claims (1)

[Claims] In a semiconductor device having an integrated circuit formed on a semi-insulating semiconductor substrate, an input/output terminal pad, and an input/output signal connection line to the integrated circuit, the integrated circuit, the input/output terminal pad, and the input/output signal line are A semiconductor device characterized in that a grounding conductor is provided around the periphery.