JPS62111450A - Semiconductor device - Google Patents

Abstract

PURPOSE:To eliminate cross talk between telephone circuits, by arranging a conductor wiring, which is connected to a semiconductor substrate, between neighboring conductor wirings. CONSTITUTION:First and second conductor wirings 11 and 12 for signal lines are formed on an insulating film 14 on the surface of a silicon substrate 13. A third conductor wiring 15 is located between the conductor wirings 11 and 12 and kept at the same potential as that of the silicon substrate 13. Most of electric lines of force generated from the conductor wirings 11 and 12 are concentrated between the conductor wirings 11 and 12 for signal wiring and the third conductor wiring 15. The electric lines of force between the conductor wirings 11 and 12 for the signal lines are negligible. Therefore, the relation of the magnitudes of stray capacitances C11, C12 and C13 becomes as follows: C11 C12>>C13. Thus, the cross talk characteristic of the device is improved to a large extent.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Application of Industry-1- The present invention relates to a semiconductor device that controls links between multiple channels, mainly in the field of voice communications such as telephone exchanges.

2. Description of the Related Art A conventional semiconductor device of this type will be described with reference to FIG. FIG. 2 is a perspective view of an MO8 type semiconductor device converted into N[118], in which 1 is a silicon substrate, and P-type silicon wafers are used for an N-channel, and N-type silicon wafers are used for a P-channel. 2 is a FIEL I oxide film formed on the silicon substrate 17, and the film thickness is usually around 1 μm. Reference numerals 3 and 4 denote conductor wirings made of a vapor-deposited aluminum film or the like.

The line width and interline gap of the conductor wirings S3 and S4 are each several micrometers, and these dimensions tend to become smaller and smaller. Naturally, there is a floating capacity ft C between these two wires.
1 exists and the gap decreases, it increases accordingly. For example, when telephone lines (A) and (B) are connected to these conductor wirings 3 and 4, crosstalk occurs between the telephone lines (A) and (B) mainly through the floating container C. The amount of crosstalk that is practically acceptable is about -90 dB or more in the audio frequency band. Achieving this value under the above wiring dimensions is a very difficult problem.

Problems to be Solved by the Invention As described above, the above-mentioned conventional configuration has a problem in that it is not possible to eliminate crosstalk between adjacent signal wirings mainly due to volumetric coupling in semiconductor devices that are becoming increasingly finer. Ta.

Means for Solving the Problems In order to solve the second generation problems, the semiconductor device of the present invention includes a semiconductor substrate and a connection between first and second conductor wirings for signal lines located adjacent to each other. This is the arrangement of the third conductor wiring.

According to the configuration described above, the third conductor wiring performs a shielding function, reducing crosstalk.

Example An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a perspective view of a semiconductor device according to an embodiment of the present invention. This semiconductor device is a MOS type and is shown in a simplified manner. In FIG. 1, 11°I2 is the first .I2 for the signal line. The second conductor wiring is formed on a silicon-based insulating film 111 of silicon dioxide 11 formed on the surface of the silicon substrate 13. Reference numeral 15 denotes a third conductor wiring, which is located between the first and second conductor wirings I+ and +2, penetrates the silicon-based insulating film 14 through a contact window 16, and is lower than the impurity concentration of the silicon substrate I3. It is connected to a slightly dense diffusion region I7. Therefore, the third conductor wiring 15 is held at the same potential as the silicon substrate 13. C11 is the stray capacitance between the conductor wiring II and 15, C12 is the stray capacitance between the conductor wiring 12 and 15, and C
0, is the stray capacitance between the conductor wirings 11 and 12.

Next, the operation will be explained. (Each conductor arrangement for line 8 a11゜1
Most of the electric lines of force generated from the conductor wiring 11.2 for each signal line. +2 and the third conductor wiring 15, and the concentration between the conductor wirings 11 and 12 for each signal line is almost negligible. Therefore, stray capacitance C1,,C
The magnitude relationship between 1□ and C is C10,≠C1□)C10, and also in relation to the conventional example shown in FIG. 2, the magnitude relationship of each stray capacitance.

C) It is easy to satisfy the relationship C1.

From the above, it can be expected that the roxtalk characteristics caused by stray capacitance between signal lines will be significantly improved by installing the third conductor arrangement 1IAis.

Effects of the Invention As described above, according to the present invention, cross 1 hake can be significantly reduced with an extremely simple and easy-to-implement configuration.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a perspective view of a conventional semiconductor device. 11...First conductor wiring, 12...Second conductor wiring,
13 silicon substrate, 15... z3 conductor wiring agent
Yoshihiro MorimotoFigure 1Figure 2

Claims (1)

[Claims] 1. A semiconductor device in which a third conductor wiring connected to a semiconductor substrate is disposed between adjacent first and second conductor wirings for signal lines.