JPH0528757Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a dry etching apparatus, and particularly to a dry etching apparatus suitable for etching using chloride gas.

[Background of the idea]

A conventional dry etching apparatus is shown in FIG. In FIG. 2, a lower electrode 4 is provided in the processing chamber 1 and is insulated from the processing chamber 1 by an upper electrode 3 and an insulator 5. As shown in FIG. Gas in the processing chamber 1 is exhausted from an exhaust nozzle 2. A high frequency power source 6 is connected to the lower electrode 4 . At the same time as the processing gas is supplied from the upper electrode 3, a discharge is generated between the upper electrode 3 and the lower electrode 4 by the high frequency power source 6, and the sample 7 placed on the lower electrode 4 is etched. At this time, since the reaction products adhere and accumulate on the inner surface of the processing chamber 1, the deposits fall onto the wafer as foreign matter, resulting in adverse effects. For this reason, it is necessary to remove the reaction products that have adhered or accumulated on the inner surface of the processing chamber 1, and methods for preventing the reaction products from adhering or for removing the deposits have been proposed. For example, in JP-A-59-143073, heated inert gas is sealed in the processing chamber 1 to evaporate and remove chloride, which is a reaction product. However, with this technique, etching must be stopped when inert gas is filled in. Furthermore, in JP-A-59-134832, the part of the lower electrode 4 covered with the sample 7 is made of SUS material with good thermal conductivity, and the part not covered with the sample 7 is made of carbon with poor thermal conductivity.
Prevents reaction products from adhering. However, this technique does not take into consideration the inner wall of the processing chamber 1, and is not sufficient to reduce reaction products adhering to the wafer. As mentioned above, in the conventional technology, the deposition of reaction products during etching,
An appropriate technique for preventing deposition has not yet been developed, and therefore, the processing chamber 1 is periodically opened to the atmosphere for artificial cleaning, which has become an obstacle to improving the productivity of dry etching equipment. There is.

[Purpose of invention]

An object of the present invention is to provide a dry etching apparatus that can economically suppress adhesion and deposition of reaction products on the inside of a processing chamber, reduce the number of times the processing chamber is cleaned, and improve productivity.

[Summary of the idea]

The present invention uses a dry etching apparatus to evacuate the inside of a processing chamber under reduced pressure, introduce a processing gas into the processing chamber, turn the gas into plasma between an upper electrode and a lower electrode, and use the plasma to etch a sample. In the processing apparatus, a cylindrical quartz cover with a height higher than the distance between the upper electrode and the lower electrode is placed between the upper electrode and the lower electrode and the inner surface of the side wall of the processing chamber, and a heater is attached to the quartz cover. This system is equipped with a quartz cover heated by a heater to evaporate the reaction products generated during the etching process before they adhere to the inner surface of the side wall of the processing chamber. This suppresses the adhesion and accumulation of reaction products to the chamber, reduces the number of times the processing chamber is cleaned, and improves productivity.

[Example of idea]

An embodiment of the present invention will be explained with reference to FIG.

The difference between FIG. 1 and FIG. 2 is that the heating means 10
is provided corresponding to the inner surface of the processing chamber 1, that is, the inner surface of the side wall of the processing chamber 1. In FIG. 1, parts, devices, etc. that are the same as those in FIG. 2 are indicated by the same reference numerals, and their explanations will be omitted.

In FIG. 1, heating means 10 is composed of a heater 11, a quartz cover 12, and a power supply device 13.
The quartz cover 12 has a hollow cylindrical structure, and the heater 11 is provided inside the quartz cover 12. The power supply device 13 is installed outside the processing chamber 1 , and the heater 11 is connected to the power supply device 13 via an introduction terminal 20 provided on the top wall of the processing chamber 1 .
The quartz cover 12 prevents discharge from occurring between the heater 11 and the upper electrode 3 and the lower electrode 4, and the position of the quartz cover 12 in the processing chamber 1 and the height of the quartz cover 12 are is at a position and height corresponding to the inner surface of the side wall of the processing chamber 1, where many reaction products adhere and accumulate. That is, the first
As shown in the figure, the upper electrode 3 is disposed between the upper electrode 3 and the lower electrode 4 and the inner surface of the side wall of the processing chamber 1.
The height is made higher than the distance between the lower electrode 4 and the lower electrode 4.

In FIG. 1, reaction products generated when sample 7 is etched using plasma are removed from a quartz cover that is heated to a temperature that evaporates even if the reaction products adhere to it due to the heat generated by heater 11. As a result, the gas is discharged from the exhaust nozzle 2 to the outside of the processing chamber 1 as a gas without adhering to or depositing on the inner surface of the side wall of the processing chamber 1 .

In this embodiment, the following effects can be obtained.

(1) It is possible to suppress the adhesion and accumulation of reaction products on the inner surface of the side wall of the processing chamber, and the number of cleanings of the processing chamber can be reduced, thereby improving productivity.

(2) Reaction products can be removed during equipment operation;
Equipment can be operated continuously and productivity can be improved.

(3) Since the quartz cover and heater are provided inside the processing chamber, the heat generation capacity of the heater can be reduced, improving economic efficiency and causing no safety problems.

In addition to the above-described embodiments, similar effects can be obtained when a high frequency power source is connected to the upper electrode and the lower electrode is grounded.

[Effect of idea]

The present invention provides an apparatus for evacuating the inside of a processing chamber, introducing a processing gas into the processing chamber, converting the gas into plasma between an upper electrode and a lower electrode, and etching a sample using the plasma. By disposing a cylindrical quartz cover whose height is higher than the distance between the upper electrode and the lower electrode between the upper electrode and the lower electrode and the inner surface of the side wall of the processing chamber, and by providing a heater on the quartz cover, It is possible to economically suppress adhesion and accumulation of reaction products on the inside of the processing chamber, reduce the number of times the processing chamber is cleaned, and thereby improve productivity.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a processing chamber showing an embodiment of a dry etching apparatus according to the present invention, and FIG. 2 is a longitudinal sectional view of a processing chamber of a conventional dry etching apparatus. DESCRIPTION OF SYMBOLS 1... Processing chamber, 3... Upper electrode, 4... Lower electrode, 6... High frequency power supply, 11... Heater, 12...
...Quartz cover, 13...Power supply device 13.

Claims (1)

[Scope of utility model registration request] In an apparatus that evacuates a processing chamber and introduces a processing gas into the processing chamber, converts the gas into plasma between an upper electrode and a lower electrode, and etches a sample using the plasma, the upper electrode and A cylindrical quartz cover having a height higher than the distance between the upper electrode and the lower electrode is disposed between the lower electrode and the inner surface of the side wall of the processing chamber, and a heater is provided on the quartz cover. Dry etching equipment.