JPH10256230A - Dry etching device, and method of catching reactive product produced by etching - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the maintenance frequency of a turbomolecular pump and an evacuation pipe by providing a chamber for catching the reactive products produced by dry etching, between a reactive processing chamber and the evacuation pipe. SOLUTION: A reactive product catching and processing chamber for positively catching reactive products is installed between a reactive processing chamber and a turbomolecular pump. A processing chamber for catching reactive products consists of an outer wall part and a reactive product catching part, and the outer wall part 13 is one for housing a reactive product catching part and is cylindrical. Moreover, when it has housed the reactive product catching part 14 in the outer wall part 13, the outer surface of the reactive product catching part and the inner surface of the outer wall part 13 are stuck fast to each other. The outer wall part 13 can be broken up to at least two parts. That is, when the outer wall part 13 is divided and the cover part is taken out, an aperture 15 appears in the main body. The reactive product catching part can be taken out easily from this aperture 15, and the simplification in the maintainability and the shortening of the time can be materialized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry etching apparatus suitable for use in, for example, manufacturing of semiconductors and the like, and a method for capturing a reaction product generated by etching.

[0002]

2. Description of the Related Art
In general, Al (including Al-based alloys), W, and Ti-based alloys are used alone or in a laminated form for the amount of wiring material of a semiconductor device. Further, halogen gas such as fluorine and chlorine has been used for the processing.

The above-mentioned wiring material can be relatively easily processed with a halogen gas, but has a problem that a boiling point of a reaction product generated at the time of etching is high. The reaction product having a high boiling point is positively adsorbed in a relatively low temperature portion, for example, in a turbo-molecular pump used as an auxiliary pump for high vacuum evacuation or in an exhaust pipe.

As a result, the reaction product accumulates in the turbo-molecular pump and the exhaust pipe, thereby deteriorating the exhaust efficiency of the apparatus, making it impossible to control the pressure to the set pressure, and causing problems such as poor processing. Was.

[0005] Therefore, it is necessary to perform regular maintenance for the inside of the turbo-molecular pump and the exhaust-side piping as in the case of the reaction processing chamber. However, in the current apparatus structure, the maintenance frequency of the exhaust system is higher than that of other process apparatuses.

In addition, the overhaul cost of the turbo-molecular pump is generally high, and it takes a long time to maintain the inside of the piping, and the loss is very large in terms of cost and equipment downtime. .

[0007] The present invention has been made in view of such a problem, and a reaction product generated by etching is:
It is an object of the present invention to provide a dry etching apparatus capable of preventing adhesion to an exhaust pipe after a turbo molecular pump, and a method for capturing a reaction product generated by etching.

[0008]

According to the dry etching apparatus of the present invention, a dry etching process using a halogen gas is performed to exhaust a gas through a reaction processing chamber for processing a wiring material of a semiconductor device and an exhaust pipe. In a dry etching apparatus having exhaust means for maintaining a reaction processing chamber at a high vacuum, a reaction product capture processing chamber for capturing a reaction product is provided between the reaction processing chamber and an exhaust pipe. .

In the method for capturing a reaction product generated by etching according to the present invention, exhaust is performed through a reaction processing chamber for processing a wiring material of a semiconductor device by dry etching using a halogen gas and an exhaust side pipe. In the dry etching apparatus having exhaust means for maintaining the reaction processing chamber at a high vacuum, a reaction product capture processing chamber for capturing a reaction product is installed between the reaction processing chamber and an exhaust-side pipe. Is the way.

According to the dry etching apparatus of the present invention,
By installing a reaction product capture processing chamber for capturing reaction products between the reaction processing chamber and the exhaust side pipe,
Reaction products generated by the etching can be prevented from adhering to the exhaust-side piping after the turbo-molecular pump.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a dry etching apparatus according to the present invention and a method for capturing a reaction product generated by etching will be described below with reference to FIGS.

FIG. 1 conceptually shows a main part of a dry etching apparatus according to the present invention. In FIG. 1, in an upper reaction processing chamber 1, a wiring material of a semiconductor device is processed by dry etching. The amount of wiring material for semiconductor devices
Al (including an Al-based alloy), W and a Ti-based alloy are used alone or in a laminated form. The processing is performed by dry etching using a halogen gas such as fluorine or chlorine.

Here, the wiring material can be relatively easily processed with a halogen gas, but generates a reaction product at the time of etching.

The temperature of the reaction processing chamber 1 and the butterfly valve 2 for controlling the pressure are controlled so as not to hinder the process. Usually, this temperature is set to about 60 ° C. This is to prevent the reaction product from adhering to the inner surfaces of the reaction processing chamber 1 and the butterfly valve 2.

The reaction chamber 1 is evacuated (not shown) through a turbo molecular pump 4 and an exhaust pipe 5.
, And a high vacuum is maintained.

Between the reaction processing chamber 1 and the turbo molecular pump 4, a small reaction product capturing processing chamber 3 for actively capturing reaction products is provided. The details of the reaction product capturing chamber 3 will be described later.

Gate valves 6 and 6 are provided between the reaction product capture processing chamber 3 and the upstream reaction processing chamber 1 and between the downstream reaction chamber 1 and the turbo molecular pump 4 to shut off the reaction products. The capture processing chamber 3 can be cut off in a vacuum.

FIG. 2 shows the configuration of the above-mentioned reaction product capturing chamber in detail. As shown in the figure, the reaction product capture processing chamber includes an outer wall (FIG. 2A) and a reaction product capture unit (FIG. 2B).

In FIG. 2A, an outer wall portion 13 accommodates a reaction product capturing portion 14 (described in detail later).
It has a cylindrical shape. When the reaction product capturing unit 14 is housed in the outer wall 13, the outer surface of the reaction product capturing unit and the inner surface of the outer wall 13 are brought into close contact with each other.

The outer wall 13 can be disassembled into at least two parts. That is, when the outer wall portion 13 is divided and one portion (hereinafter, referred to as a “lid portion”) is removed, as shown in FIG. 2A, the opening portion 15 is formed in the other portion (hereinafter, referred to as a “main body portion”). Appears. The reaction product capturing section can be easily taken out from the opening 15.

When the lid is inserted into the opening 15 of the main body 16, vacuum leakage is prevented between the lid and the main body 16 by a seal. The screw hole 7 of the main body 16 is a hole for screwing a screw to fix the lid to the main body 16 after the lid is fitted into the opening.

The cooling medium hole 8 of the main body 16 is a tube through which a cooling medium flows, and the cooling medium hole is provided in the lid similarly. When the lid is inserted into the opening 15 of the main body 16, the cooling medium hole 8 of the main body and the cooling medium hole of the lid are connected in a liquid-tight state.

The outer wall 13 has a cooling means as described above in order to improve the efficiency of capturing the reaction product. That is, a mechanism for circulating the cooling medium in the outer wall portion is provided. Water is used as a cooling medium. The temperature of the cooling medium is desirably in the range of 15 to 20C. In order to make the temperature of the cooling medium lower than 15 ° C., there is a disadvantage that special piping is required and equipment cost is increased.
This is because if the temperature is higher than 0 ° C., the capture efficiency decreases. In addition,
Of course, cooling media other than water can be used.

As described above, when the reaction product capturing section 14 is housed in the outer wall section 13, the outer surface of the reaction product capturing section 14 and the inner surface of the outer wall section 13 are in close contact.
Heat transfer from the reaction product capturing section 14 to the outer wall section 13 is efficiently performed.

Therefore, by circulating the cooling medium in the outer wall portion 13, the reaction product capturing portion 14 can be cooled, and the fins 11 (described in detail later) can be cooled. As a result, the efficiency of capturing the reaction products in the fins 11 can be improved.

As shown in FIG. 2B, the reaction product capturing section 14 has a cylindrical shape (FIG. 2B shows an axial sectional view of the cylinder). Further, the inside of the reaction product capturing section 14 has a structure to increase its surface area. In other words, the inner surface area of the reaction product capturing unit 14 is larger than the inner surface area when the reaction product capturing unit 14 is assumed to be composed of only a cylinder. That is, a portion for increasing the surface area (hereinafter, referred to as a “surface area increasing portion”) is provided.

In this embodiment, as shown in FIG. 2B, the reaction product trapping section 14 is provided with fins 11 as a surface area enlargement portion to such an extent that the exhaust efficiency is not significantly deteriorated. The surface area has been increased and the capture efficiency has been improved.

The fin of FIG. 2B has a three-stage structure, and the diameter of the hole provided at the center decreases as going downward.
This is because the contact area is increased toward the downstream side of the vacuum to enhance the efficiency of capturing the reaction product.

The shape of the fin is not limited to that shown in FIG. 2B. The reaction product capturing section may have a double cylinder shape and a metal plate may be spirally provided between the two. In addition, it is a matter of course that other shapes can be adopted as long as the shape increases the contact area.

The reaction product capturing section 14 is made of aluminum. This is because the thermal conductivity is large and the capture efficiency can be increased. The material of the product capturing unit is not limited to aluminum as described above, and other metals such as SUS can be used.

As a constituent material, hydrofluoric acid treatment (Al
It is desirable that the material be able to withstand withstand water treatment (used for removing system-based reaction products) and water treatment (used for removing Ti-based and W-based reaction products).

Incidentally, even if the cooling medium is not circulated through the outer wall, the reaction product can be captured even at room temperature because the area of the enlarged area is large.

As described above, according to the present embodiment, the frequency of maintenance of the turbo molecular pump and the exhaust-side piping is reduced by providing the reaction product capturing chamber between the reaction processing chamber and the turbo molecular pump. This is effective in terms of cost and equipment productivity such as machine downtime.

Further, the reaction product capturing chamber is cut off in a vacuum, so that the capturing chamber can be overhauled without stopping the reaction processing chamber and the turbo molecular pump, thereby simplifying maintenance and shortening the maintenance time. effective.

It should be noted that the present invention is not limited to the above-described embodiment, but can adopt various other configurations without departing from the gist of the present invention.

[0036]

As described above, according to the present invention,
By providing a reaction product capture chamber between the reaction processing chamber and the turbo-molecular pump, it is possible to prevent the reaction products from accumulating in the turbo-molecular pump and the exhaust-side piping, and maintain high exhaust efficiency of the device. can do.

Further, it is possible to reduce the frequency of maintenance of the turbo molecular pump and the exhaust side piping, thereby reducing the cost and the downtime of the machine.

Further, by separating the reaction product capture processing chamber in a vacuum, the capture processing chamber can be overhauled without stopping the reaction processing chamber and the turbo molecular pump, thereby simplifying maintenance and shortening the maintenance time. Can be planned.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a main part of a dry etching apparatus of the present invention.

FIG. 2 is a configuration diagram schematically showing a reaction product capture processing chamber of the dry etching apparatus of the present invention.

[Explanation of symbols]

Reference Signs List 1 reaction processing chamber, 2 butterfly valve, 3 reaction product capture processing chamber, 4 turbo molecular pump, 5 exhaust side piping, 6 gate valve, 7 screw hole, 8 cooling medium hole, 9 cooling medium inlet, 10 cooling medium outlet , 11 fins, 13 outer wall, 14 reaction product trap, 15
Opening, 16 body

Claims (18)

[Claims] 1. A reaction processing chamber for processing a wiring material of a semiconductor device by dry etching using a halogen gas, and an exhaust means for maintaining the reaction processing chamber at a high vacuum by exhausting air through an exhaust pipe. A dry etching apparatus comprising: a reaction product capture processing chamber for capturing a reaction product between the reaction processing chamber and the exhaust-side pipe. 2. The dry etching apparatus according to claim 1, wherein the reaction product trapping treatment chamber has a surface area increasing portion provided inside thereof. 3. The dry etching apparatus according to claim 1, wherein the reaction product capturing chamber has fins provided inside thereof. 4. The reaction product capturing chamber includes a reaction product capturing section provided with a surface area increasing portion inside thereof, and an outer wall section accommodating the reaction product capturing section. The dry etching apparatus according to claim 1, wherein 5. The reaction product capture processing chamber includes a reaction product capture section having a surface area enlargement section provided inside thereof and an outer wall section accommodating the reaction product capture section. 2. The dry etching apparatus according to claim 1, comprising a main body having an opening through which the reaction product capturing section can be taken out, and a lid body fitted into the opening of the main body. 6. The reaction product trapping treatment chamber includes a reaction product trapping section provided with a surface area enlargement section inside thereof and an outer wall section accommodating the reaction product trapping section. 2. The dry etching apparatus according to claim 1, wherein a gate valve for shutting off a vacuum is provided between the processing chamber and the upstream reaction processing chamber, and between the downstream exhaust pipe. 7. The dry etching apparatus according to claim 1, wherein the reaction product capturing processing chamber has cooling means for cooling the reaction product capturing section. 8. The reaction product capturing chamber according to claim 1, wherein the reaction product capturing processing chamber has cooling means for cooling the reaction product capturing section, and has a surface area expanding section provided inside the cooling section. Dry etching equipment. 9. The dry etching according to claim 1, wherein the reaction product capturing chamber has cooling means for cooling the reaction product capturing section, and fins are provided inside the cooling means. apparatus. 10. The reaction product capturing processing chamber has a cooling means for cooling the reaction product capturing section, and further includes a reaction product capturing section provided with a surface area expanding section inside the reaction product capturing section, and a reaction product capturing section. 2. The dry etching apparatus according to claim 1, wherein the dry etching apparatus comprises an outer wall for storing the capturing unit. 11. A reaction product trapping treatment chamber has a cooling means for cooling a reaction product trapping part, and a reaction product trapping part provided with a surface area enlarging part inside thereof, and a reaction product trapping part. An outer wall for accommodating the capturing portion, wherein the outer wall comprises a main body having an opening from which the reaction product capturing portion can be taken out, and a lid body fitted into the opening of the main body. The dry etching apparatus according to claim 1, wherein 12. The reaction product trapping treatment chamber has a cooling means for cooling the reaction product trapping unit, and further has a reaction product trapping unit provided with a surface area enlargement part inside thereof, and a reaction product trapping unit. An outer wall for accommodating the capture unit, and providing a gate valve for vacuum shutoff between the reaction product capture processing chamber and the upstream reaction processing chamber, and between the downstream exhaust pipe. The dry etching apparatus according to claim 1, wherein: 13. A reaction processing chamber for processing a wiring material of a semiconductor device by dry etching using a halogen gas, and an exhaust means for maintaining the reaction processing chamber at a high vacuum by evacuating through a gas exhaust side pipe. A reaction product generated by etching, wherein a reaction product capture processing chamber for capturing a reaction product is installed between the reaction processing chamber and the exhaust side pipe of the dry etching apparatus having How to capture. 14. The reaction product trapping treatment chamber is provided with a surface area expanding portion inside thereof.
A method for capturing a reaction product generated by the etching described above. 15. The method for capturing a reaction product generated by etching according to claim 13, wherein a fin is provided inside the reaction product capture processing chamber. 16. The method for capturing a reaction product generated by etching according to claim 13, wherein the reaction product capturing processing chamber has cooling means for cooling the reaction product capturing section. 17. The reaction product capturing processing chamber has cooling means for cooling the reaction product capturing section, and further includes a surface area expanding section inside the cooling section.
A method for capturing a reaction product generated by the etching described above. 18. The etching process according to claim 13, wherein the reaction product capturing processing chamber has cooling means for cooling the reaction product capturing section, and fins are provided inside the cooling means. A method for capturing generated reaction products.