JPS6327023A - Dry etching device - Google Patents

Abstract

PURPOSE:To etch a substrate uniformly with excellent reproducibility by mounting a perforated plate to a counter electrode, supplying an etching gas and prventing blockage of the electrode to which the etching gas is fed. CONSTITUTION:A perforated plate 8 for uniformly supplying a substrate 4 with an etching gas such as a carbon fluoride group gas, such as C2F6, CHF3 or the like is set up to an opposed surface to an electrode 3 facing an electrode 2. The perforated plate 8 consists of silicon carbide or a material coated with silicon carbide. Consequently, since the etching gas is introduced through the perforated plate 8, holes are not blocked by a polymerized film generated during etching, thus uniformly supplying the substrate 4 with the etching gas at all times. Accordingly, the substrate 4 is etched equally with excellent reproducibility.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dry etching apparatus, and particularly to a dry etching apparatus suitable for a one-node coupling type.

[Conventional technology]

The conventional dry etching device was developed in U.S. Pat.
As described in No. 36 or JP-A-57-185982, a sintered or sintered porous electrode was used to uniformly supply the etching gas onto the substrate.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not take into account the reproducibility of etching, and when etching silicon oxide using a fluorocarbon gas such as C2F or CHF3 as an etching gas, processing 1; As the number of porous electrodes increases, eight polymeric films consisting of porous electrodes C, H, and F are deposited to close the gaps between the porous electrodes.

As a result, the flow of the etching gas becomes non-uniform, the uniformity of the etching rate decreases, and the reproducibility of etching cannot be obtained.

Further, when the porous electrode is a one-node bonding method and is made of a soft material such as carbon, there are problems in that the substrate is contaminated by sputtering by ions, and the electrode wears out quickly.

SUMMARY OF THE INVENTION An object of the present invention is to provide a dry etching apparatus that can uniformly etch a sample with good reproducibility and reduce contamination of the sample and wear and tear of the electrodes.

[Means for solving problems]

The above purpose is to provide a processing chamber to which a charcoal-based gas is supplied as an etching gas and which is evacuated to a predetermined pressure; a sample stage provided within the processing chamber and on which a sample is placed at ground potential;
a counter electrode provided in the processing chamber opposite to the sample stage and connected to a high frequency power source; a perforated plate with a surface facing the electrode surface of the counter electrode, the perforated plate made of silicon carbide or carbonized This is achieved by using a material coated with silicon.

[For production]

Etching gas is released from a perforated plate provided on the counter electrode, and because the holes in the perforated plate through which the gas flows out are large, they are not blocked by the polymer film, and the etching gas is always uniformly supplied to the top of the sample. (It can be etched uniformly.)

In addition, by using silicon carbide as the material of the porous plate even after sputtering, there is no contamination of the sample when etching the silicon oxide film, and there is less wear (replacement frequency).

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows the structure of a dry etching apparatus. Inside the vacuum chamber l, which is a processing chamber, there are electrodes 2 parallel to each other,
Electrode 3, which is a sample stage on which a substrate is placed, is at ground potential, and electrode 2, which is a counter electrode, is connected to a high frequency power source 7 having a 1f frequency of 13.56 MHz.

The electrode 3 is made of a conductive material such as M, and is covered with a cover 5 made of an insulating material such as alumina except for the part on which a substrate 4 as a sample is placed. Electrode 2
An etching gas such as C2F6 is applied to the surface facing the electrode 3.
Alternatively, a porous plate 8 is provided to supply carbon heptafluoride gas such as CHF to the substrate 4 in a negative manner.

As shown in FIG. 2, the perforated plate 8 is provided with holes having a diameter of about 0.5 degrees, for example, at a pitch of 10 m. The pore size and pitch can be selected within 0.2-1 m (pore diameter) and 1-10 fi (pitch). The porous plate 8 is made of silicon carbide or a material coated with silicon carbide.

As described above, according to this embodiment, since the etching gas is introduced through the perforated plate 8 with a large gap, the holes are not blocked by the polymer film generated during etching, and the etching gas is always uniformly introduced. Since it is supplied to the substrate, the substrate can be uniformly etched with good reproducibility. In addition, since the porous plate is made of silicon carbide or a material coated with silicon carbide, when etching a silicon oxide film, there is no contamination of the substrate, and sputtering due to ions is less likely to occur than with carbon. Since there is little wear and tear, the frequency of replacement can be reduced.

〔Effect of the invention〕

According to the present invention, since the etching gas is supplied by providing the perforated plate on the counter electrode, the electrode to which the etching gas is supplied is not blocked, and the sample can be etched uniformly with good reproducibility. Furthermore, since the porous plate substrate is made of silicon carbide or a material coated with silicon carbide, there is no contamination of the sample and there is less consumption due to ion sputtering.

[Brief explanation of drawings]

FIG. 1 shows a dry etching example of an embodiment of the present invention! J
2 is a sectional view of M, and FIG. 2 is a plan view of the perforated plate shown in FIG.

Claims (1)

[Claims] 1. A processing chamber in which a fluorocarbon gas is supplied as an etching gas and is evacuated to a predetermined pressure, a sample stand provided within the process chamber and on which a sample is placed at ground potential, and a sample stand facing the sample stand. a counter electrode provided in the processing chamber and connected to a high frequency power source, a surface of the counter electrode facing the electrode surface is a porous plate, and the porous plate is made of a material coated with silicon carbide or silicon carbide. A dry etching device that is characterized by: