JPH09152154A - Exhaust method and device and semiconductor device formed based on the device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a reaction product or the like from being deposited on the inner surface of a pipe by producing a temperature gradient and thermophoresis. SOLUTION: Heaters 7 to 13 are mounted a specified positions of an exhaust air pipeline 4 wherein temperature control is carried by drawing a vacuum and at the same time operating control devices 14 to 20. As for the temperatures of the respective heaters ranging from 7 to 13, the heater 7 which is located at the nearest position of a processing chamber 2 indicates the highest temperature gradient while the heater 13, which is located at the nearest position of an air suction part of a dry pump 5, shows the lowest temperature gradient. In the exhaust air pipeline 4 which is subjected to the heat gradient, a reaction product exhausted from the processing chamber 2 is guided to the dry pump 5 by thermophoresis driven from a high temperature area to a low temperature area without being deposited on the inner surface of the exhaust air pipeline 4 so that the reaction product may be discharged from a duct 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust method and apparatus and a semiconductor manufacturing apparatus constructed by using the same, and more particularly, to an exhaust system piping in a semiconductor manufacturing apparatus for performing predetermined processing under reduced pressure such as plasma processing. The present invention relates to a technique that is effective when applied to the reduction of particles deposited on the surface.

[0002]

2. Description of the Related Art According to a study made by the present inventor, in a semiconductor manufacturing apparatus such as a dry etching apparatus or a sputtering apparatus, a vacuum pump such as a turbo pump or a dry pump is used for vacuuming or depressurizing a processing chamber. There is. The processing chamber and the vacuum pump are connected by, for example, piping.

As an example in which a semiconductor manufacturing apparatus of this kind is described in detail, Press Journal Co., Ltd., issued October 20, 1994, November 1994, Volume 13, No. 12, "Monthly Semiconduct."
r World (Semiconductor World) "P93
~ P96, and this document describes the technical trends of turbo molecular pumps.

[0004]

However, the inventor of the present invention has found that the exhaust technology of the processing chamber as described above has the following problems.

That is, the inside of the pipe connecting the processing chamber and the vacuum pump is at a substantially constant temperature, and reaction products such as carbon, fluorine and aluminum floating in the processing chamber, particles and the like are accumulated to form a vacuum. The pump exhaust efficiency is a problem.

Further, the deposition of reaction products, particles, etc. is conspicuous in a curved pipe portion, that is, an elbow-shaped pipe portion.

Furthermore, maintenance must be frequently performed to remove the accumulation of reaction products, particles, etc. in the pipe, and the reduction in throughput is also a problem.

An object of the present invention is to provide an exhaust method and apparatus capable of generating a temperature gradient in a pipe and preventing deposition of reaction products and the like in the pipe by thermal aging, and semiconductor manufacturing using the same. To provide a device.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0010]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

That is, in the exhaust method of the present invention, the exhaust gas is exhausted while controlling the temperature of the exhaust system pipe for exhausting the exhaust gas for performing a predetermined process so that the temperature gradient becomes higher toward the process chamber. Is exhausted.

Further, in the exhaust system of the present invention, the exhaust system pipe for exhausting the exhaust gas in the processing chamber for performing the predetermined processing is provided with a heating means that becomes higher in temperature as it gets closer to the processing chamber and lower as it gets farther from the processing chamber. It is provided.

Further, in the exhaust system of the present invention, the heating means is composed of a plurality of heating means having different heating temperatures, and a structure in which a plurality of heating means are provided at predetermined positions in the pipe.

Further, the exhaust device of the present invention is provided with temperature control means for controlling the heating means to an arbitrary set temperature.

Further, in the exhaust device of the present invention, the heating means is a heat tape which is a film heater.

Further, the semiconductor manufacturing apparatus of the present invention is configured by using the exhaust device as an exhaust system.

As described above, since a heat gradient is generated in the exhaust pipe and the heat is exhausted by the heat in the pipe, the exhaust can be efficiently exhausted without depositing particles in the pipe, and the plasma treatment is performed. By using the same in a semiconductor manufacturing apparatus that performs such processes, reaction products generated during processing can be efficiently exhausted, and particles such as reaction products deposited in the pipe can be significantly reduced.

[0018]

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

FIG. 1 is an explanatory view of a dry etching apparatus provided with an exhaust system according to an embodiment of the present invention, and FIG.
FIG. 3 is a structural explanatory view of a heater provided in an exhaust device according to one embodiment of the present invention, and FIG. 3 is a temperature control diagram in each portion of an exhaust pipe by the exhaust device according to one embodiment of the present invention.

In the present embodiment, a dry etching apparatus (semiconductor manufacturing apparatus) 1 that etches a thin film formed on the surface of a semiconductor wafer, which will be described later, on a whole surface or a specified place by a required thickness is used for etching. A processing chamber 2 for carrying out is provided.

An exhaust port 2a for evacuating the inside of the processing chamber 2 is provided at the bottom of the processing chamber 2.

Further, a table 2b on which a semiconductor wafer (object to be processed) W is placed is provided in the center of the processing chamber 2, and the semiconductor wafer W placed on the table 2b is etched.

Further, the dry etching apparatus 1 is provided with a turbo molecular pump 3 which is a vacuum pump for transferring gas by giving momentum to gas molecules colliding with the surface thereof by a rotor having turbine type blades and rotating at high speed. Has been.

The exhaust port 2a in the processing chamber 2 is
It is connected to the intake part (not shown) of the turbo molecular pump 3,
The exhaust unit 3a of the turbo molecular pump 3 is connected to, for example, an exhaust pipe (pipe) 4 made of stainless steel in order to perform exhaust by vacuuming.

Further, the dry etching apparatus 1 is provided with a dry pump 5 which is a vacuum pump for rough evacuation of the turbo molecular pump 3, and an intake portion 5a of the dry pump 5 has the other end portion of the exhaust pipe 4. Are connected. further,
An exhaust duct 6 is connected to the exhaust portion 5b of the dry pump 5.

In the exhaust pipe 4 of the dry etching apparatus 1, the turbo molecular pump 3 to the dry pump 5 are connected.
Heaters (heating means) 7 to 13 at predetermined intervals so that a temperature difference, that is, a thermal gradient is generated in the exhaust pipe 4 connected to
Is provided.

Here, when the heaters 7 to 13 cannot be attached due to the shape and position of the exhaust pipe 4, a heat tape (not shown) made of a film heater may be used.

Further, the dry etching apparatus 1 is provided with temperature control devices (temperature control means) 14 to 20 for setting and controlling the temperatures of the respective heaters 7 to 13.
The heaters 7 to 13 and the temperature control devices 14 to 20 are connected by a wiring 21.

The turbo molecular pump 3, the dry pump 5, the exhaust pipe 4, the heaters 7 to 13, the temperature control devices 14 to 20 and the wiring 21 constitute an exhaust system (exhaust device) HS.

Further, the heaters 7 to 13 in the exhaust pipe 4
As shown in FIG. 2, for example, the mounting structure is such that the heater 7 covers the outer peripheral portion of the exhaust pipe 4, and the outer peripheral portion of the heater 7 is provided with a heat insulating material 22 made of rubber, for example. There is.

The heater 7 is a temperature control device 1 for setting the temperature of the heater 7 and controlling the set temperature to be constant.
4 and the wiring 21.

It should be noted that another heater 8 provided in the exhaust pipe 4
13 to 13 (FIG. 1) have the same configuration.

Next, the operation of the present embodiment will be described.

First, in each of the heaters 7 to 13 attached to the exhaust pipe 4, before the etching is started, an operator inputs a temperature set value to the temperature control devices 14 to 20 in advance, and the turbo molecular pump Simultaneously with the evacuation of the vacuum pump 3 and the dry pump 5, the temperature controllers 14 to 20 start control so that the heaters 7 to 13 maintain the set temperature.

Then, the processing chamber 2 is evacuated by the turbo molecular pump 3 and the dry pump 5,
When the processing chamber 2 is depressurized to a predetermined value, the semiconductor wafer W placed on the table 2b is etched by using the active gas plasma under reduced pressure in the processing chamber 2.

Next, the temperature setting of these heaters 7 to 13 is shown in FIG. In FIG. 3, each heater 7
13 are indicated by A to G, respectively.

In setting the temperatures of the heaters 7 to 13, as shown in FIG. 3, the temperature of the heater 7 (A) attached to the exhaust pipe 4 closest to the exhaust portion 3a of the turbo molecular pump 3 is the highest. The temperature gradient is such that the temperature of the heater 13 (G) closest to the intake portion 5a of the dry pump 5 is the lowest.

Here, the heater 7 (A) and the heater 8 (B)
Also, the temperatures of the heater 11 (E) and the heater 12 (F) are the same.

This is the part of the elbow in the exhaust pipe 4,
That is, in the portion where the heater 8 (B) and the heater 12 (F) are attached, the heater 7 (A) and the heater 8
(B) By preventing the temperature difference between the heater 11 (E) and the heater 12 (F), it is possible to prevent the reaction product from easily accumulating on the elbow portion.

Then, in the exhaust pipe 4 in which a thermal gradient is generated by the heating of the heaters 7 to 13 attached to the exhaust pipe 4, the reaction product exhausted from the processing chamber 2 is driven from the high temperature region to the low temperature region. The thermal permeation leads to the dry pump 5 without being deposited on the exhaust pipe 4, and is exhausted from the duct 6.

As a result, in the present embodiment, particles such as reaction products deposited on the exhaust pipe 4 can be significantly reduced due to thermal aging of the exhaust pipe 4 having a temperature gradient generated by the heaters 7 to 13. Therefore, maintenance becomes easy, and the interval of regular maintenance can be lengthened.

Further, even if a temperature gradient is generated by repeatedly heating the heaters 7 to 13 at a predetermined temperature in order, particles such as reaction products deposited on the exhaust pipe 4 will be significantly increased. It can be reduced.

Although the invention made by the inventor has been specifically described based on the embodiments of the present invention, the present invention is not limited to the above embodiments, and various modifications may be made without departing from the gist of the invention. Needless to say, it can be changed.

For example, in the above-described embodiment, each heater is controlled to a preset temperature by the temperature control device to generate a temperature gradient, but heaters having different heat generation amounts are used without using the temperature control device. By providing a temperature gradient by providing the exhaust pipe at a predetermined position, particles such as reaction products deposited in the exhaust pipe can be favorably reduced by thermal aging.

In the above embodiment, a plurality of heaters are used to generate a heat gradient in the exhaust pipe, but the exhaust pipe may be covered with one heater.

In this case, a heater is used which has a heat distribution such that the closer it is to the processing chamber the higher temperature region and the farther it is from the processing chamber the lower temperature region.

Further, although the dry etching apparatus has been described in the above embodiment, for example, CVD (C
chemical Vapor Deposition
n) A semiconductor manufacturing apparatus having an exhaust pipe such as an apparatus or a sputtering apparatus can significantly reduce particles in the pipe.

[0048]

Advantageous effects obtained by typical ones of the inventions disclosed by the present application will be briefly described as follows.
It is as follows.

(1) According to the present invention, the exhaust pipe for exhausting the exhaust gas from the processing chamber is provided with the heating means having a temperature gradient of a higher temperature as it is closer to the processing chamber, so that the exhaust pipe is deposited. Particles can be significantly reduced.

(2) Further, in the present invention, due to the above (1), manufacturing defects due to a decrease in exhaust speed can be reduced, simplification in maintenance of the piping of the exhaust system and long-term internbal of regular maintenance. Can be converted.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a dry etching apparatus provided with an exhaust device according to an embodiment of the present invention.

FIG. 2 is a structural explanatory view of a heater provided in the exhaust device according to the embodiment of the present invention.

FIG. 3 is a temperature control diagram in each part of the exhaust pipe by the exhaust device according to the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dry etching apparatus (semiconductor manufacturing apparatus) 2 Processing chamber 2a Exhaust port 2b Table 3 Turbo molecular pump 3a Exhaust part 4 Exhaust pipe (pipe) 5 Dry pump 5a Intake part 5b Exhaust part 6 Duct 7-13 Heater (heating means) 14 -20 Temperature control device (temperature control means) 21 Wiring 22 Heat insulating material W Semiconductor wafer (processing target) HS Exhaust system (exhaust device)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H01L 21/3065 H01L 21/302 B

Claims (6)

[Claims] 1. The exhaust gas is exhausted while controlling the temperature of a pipe of an exhaust system for exhausting exhaust gas in a processing chamber for performing a predetermined process so that the temperature gradient becomes higher toward the processing chamber. How to exhaust. 2. A heating means is provided in a pipe of an exhaust system for exhausting exhaust gas in a processing chamber for performing a predetermined processing, the heating means having a higher temperature as it is closer to the processing chamber and a lower temperature as it is farther from the processing chamber. And exhaust system. 3. The exhaust system according to claim 2, wherein the heating means comprises a plurality of heating means having different heating temperatures, and the heating means has a structure in which a plurality of the heating means are provided at predetermined positions in the pipe. A characteristic exhaust system. 4. The exhaust system according to claim 3, further comprising temperature control means for controlling the heating means to an arbitrary set temperature. 5. The exhaust system according to claim 3, wherein the heating means is a heat tape including a film heater. 6. A semiconductor manufacturing apparatus comprising the exhaust device according to claim 2 for an exhaust system.