JPS6366394B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a parallel plate electrode type dry etching apparatus.

For etching processing in the manufacturing process of semiconductor devices, various dry etching apparatuses are provided in place of so-called wet etching apparatuses, which do not have the problem of drainage treatment and are also capable of etching fine patterns. As one type,
A so-called parallel plate electrode type dry etching apparatus is used in which a flat upper electrode and a lower electrode are arranged parallel to each other. However, this type of apparatus has the disadvantage that the etching rate varies widely within the wafer depending on the method of injecting or evacuation of the etching gas. In other words, even if the etching gas is injected from the upper counter electrode and exhausted from the lower part of the chamber, the supply of gas within the wafer is uneven, resulting in unevenness of the etchant and variations in the etching rate. It is difficult to perform good etching because of the large thickness and the deposition of reaction products and the like.

SUMMARY OF THE INVENTION In view of these drawbacks, it is an object of the present invention to provide a dry etching apparatus that has small variations in etching speed within a wafer and is capable of etching at high speed.

In the present invention, the upper electrode is provided with a plurality of etching gas inlets and exhaust ports, so that the etching gas can be injected and exhausted simultaneously and uniformly to the wafer through the upper electrode.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a longitudinal sectional view of an embodiment of a parallel plate electrode type dry etching apparatus according to the present invention.

A flat lower electrode 3 on which a wafer 4 is placed is provided on the lower side of the vacuum chamber 1 . An upper electrode 2 is provided above and opposite to the lower electrode 3. 7 is a high frequency power source connected to the lower electrode 3.

The upper electrode 2 is shaped like a duct and has a partition plate 2 inside.
1 into two parts, and one side is connected to the etching gas injection system 8.
and the other end is communicated with the exhaust system 9, respectively.
Further, elongated etching gas inlets 5 and exhaust ports 6 are alternately provided on the entire lower surface of the upper electrode 2 facing the lower electrode 3. All of the exhaust ports 6 are connected to the exhaust system 9, and the injection ports 5 are separated from the space of the exhaust system 9 by a duct 22 provided on the inner wall of the upper electrode 2, and all of them are configured to communicate with the injection system 8. ing.

With the above configuration, the etching gas can be injected and exhausted simultaneously and uniformly, and the gas flow on the wafer 4 can be minimized, so that the wafer 4 is always supplied with new etchant, making it extremely Etching can be performed at a high speed with good uniformity. In this embodiment, the etching rate of the wafer 4 is 15% or less, and the etching rate is also high.

In the embodiment, a cathode coupling type reactive ion etching apparatus has been described, but it goes without saying that the present invention can also be applied to an anode coupling type plasma etching apparatus. In addition, by reducing the electrode spacing to about 5 to 20 mm, it is possible to
It is also possible to obtain an etching rate higher than that.
Furthermore, the shape of the upper electrode 2 is not limited to the shape of the embodiment.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a parallel plate electrode type dry etching apparatus according to the present invention. In the figure, 1 is a vacuum chamber, 2 is an upper electrode, 3 is a lower electrode, 4 is a wafer, 5 is an etching gas injection port, 6 is an exhaust port, 7 is a high frequency power supply, 8 is an etching gas injection system, and 9 is an exhaust system .

Claims (1)

[Claims] 1. In a parallel plate electrode type dry etching apparatus that includes a flat lower electrode on which a substrate to be etched is placed and a flat upper electrode facing parallel to the lower electrode, an etching gas injection port is provided in the upper electrode. and a plurality of exhaust ports, each inlet communicating with an etching gas injection system path, and each exhaust port communicating with an exhaust system path.