JPS62179117A - Plasma processor - Google Patents

Abstract

PURPOSE:To improve the reliability on monitor to plasma processing state by a method wherein any reactive products are prevented from bonding on a plasma light taking in part. CONSTITUTION:A specimen 4 is mounted on a specimen base 3; the pressure in a processing chamber 13 is reduced and exhausted (a) down to the specific value by leading in process gas (b) from a gas supply piping 5; and the specimen 4 is impressed with microwaves from a magnetron 6 through a waveguide 7. Next, the process gas is changed into plasma by multiplying the microwaves by magnetic field to etch the specimen 4. Finally, plasma light is taken in from a lighting hole 14 as a lighting part through the intermediary of a quartz fiber 9 using the intensity change of specific wavelength in emission of plasma light taken place in process of etching the specimen 4 and after finishing the etching process to analyze the plasma light by an emitted light analyzer 10. Through these procedures, the end point of etching process can be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plasma processing apparatus, and particularly to a plasma processing apparatus suitable for improving the reliability of plasma emission analysis during plasma processing.

[Conventional technology]

Conventionally, as described in, for example, Japanese Unexamined Patent Application Publication No. 57-120674, a method is known in which the emission spectrum of the etched knob material is extracted during etching to detect the progress of etching. This takes in the emission spectrum through a window installed in the etching and detects it through a spectrometer, photodetector, amplifier, and recorder.

[Problem that the invention seeks to solve]

The above conventional technology depends on the type of processing gas used for processing.

Etching materials, discharge conditions for turning into plasma, etc.
As a result, adhesive reaction products are generated, which adhere to the emission spectrum, i.e., the window for taking in the plasma light, and reduce the amount of plasma light transmitted, making it difficult to detect the progress of etching. No consideration was given to the problems that may occur, and there was a problem in ensuring the reliability of the etching device.

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma processing apparatus that can prevent reaction products from adhering to a plasma light collecting section and improve the reliability of monitoring the processing status during plasma processing.

[Means to solve the problem]

The above object is achieved by making the plasma light collection part into a hole and connecting it with a gas supply path for gas flowing into the processing chamber.

[For production]

A gas flow toward the processing chamber is formed in the plasma light lighting section, in other words, a lighting section is provided in the gas supply path, and reaction products generated in the processing chamber are caused to fly by this gas flow. It is possible to prevent adhesion and prevent contamination of the lighting area.

〔Example〕

Hereinafter, one embodiment of the present invention will be explained with reference to Figure 5IJ1 and the second factor.

FIG. 1 shows in this case a magnetic field microwave plasma etching apparatus. The processing chamber 13 is composed of a chatter bar 2 in which a sample stage 3 is installed, and a discharge tube l made of quartz or alumina. A waveguide 7 with a magnetron roller attached to the end thereof is provided above the processing chamber 13, and a magnetic field coil 8 is provided on the side of the processing chamber 13 via the waveguide 7 which further covers the discharge tube 1. be. The lower part of the chamber 2 is connected to an exhaust system (not shown), and the side of the chamber 7 is provided with a lighting hole 14, which is a quartz fiber 9 and a gas supply path, as shown in FIG. The gas supply pipe 5 is not connected to the gas supply pipe 5. In this case, the gas supply pipe 5 is connected to a gas supply device (not shown). The quartz fiber 9 is connected to the optical emission analyzer lO and constitutes plasma emission detection means.

With the above configuration, the sample 4 is placed on the sample stage 3, and the processing chamber 1
A process gas is introduced into the processing chamber 13 from the gas supply pipe 5, the pressure inside the processing chamber 13 is reduced and maintained at a predetermined value, and microwaves from the magnetron 6 are applied through the waveguide 7, and a magnetic field is further applied. A magnetic field is applied by the coil 8, and the process gas is turned into plasma by the synergistic effect of the microwave and magnetic field, and the sample is etched. Taking advantage of the fact that the etching changes in the etching direction, plasma emission is taken in through the quartz fiber 9 from the lighting hole 14, which is a lighting section, and analyzed by the optical emission analyzer v11O to determine the end point of etching.

2, the plasma light is transmitted through the lighting hole 1 as shown in Figure 2.
In this case, the fiber enters the quartz fiber 9 straightly installed in the quartz fiber 9 without being disturbed on the way, and in this case,
From the gas supply pipe 5 provided with a right-angled water column in the lighting hole 14,
Process gas is sent into the processing chamber 13 through the lighting hole 14 .

As described above, according to this embodiment, since the process gas flows in the direction of the reaction chamber in the lighting hole 14 between the quartz fiber 9 and the processing chamber 13, adhesive reaction products are prevented from reaching the quartz fiber 9. Therefore, contamination of the quartz fiber 9 can be prevented.

In this embodiment, the process gas was flowed through the lighting hole 141, but if the gas does not affect the process characteristics of plasma treatment, this gas may be flowed through the lighting hole 14, and the process gas may be passed through another introduction path. It may also be supplied from

Next, a second embodiment will be explained with reference to FIG.

In this figure, the same symbols as in FIG. 2 indicate the same members.

This figure differs from FIG. 2 in that a heater 11 is attached to the quartz fiber 9 so that it can be heated. Thereby, the same effect as in the previous embodiment can be obtained, and the effect of preventing the adhesive reaction product from adhering to the quartz fiber 9 can be further enhanced by this heating.

Furthermore, a third embodiment will be explained with reference to FIG.

In this figure, the same reference numerals as in FIG. 2 indicate the same members, and the difference between this figure and FIG.
The point is that there is a vacuum valve hill between the two. According to this embodiment, there are effects similar to those of the above-mentioned embodiment, and
Even if the quartz fiber 9 is contaminated by adhering reaction products and needs to be cleaned, by closing the valve and then pulling out the quartz fiber 9, maintenance can be performed without leaking the entire reaction chamber to atmospheric pressure. Equipment maintenance time can be reduced.

In this case, it is better to install a leak pipe and/or an exhaust pipe between the valve and the quartz fiber 9. In addition, in this case, the valve stem is quartz fiber 9 in the open state.
Needless to say, it is of a type that allows you to see into the reaction chamber from the inside.

In the embodiments described above, a magnetic field microwave etching apparatus M was used as the etching apparatus UR, but the present invention is not limited to this type of etching apparatus.

Furthermore, although quartz fiber is used as an example of the plasma emission light-receiving section in this embodiment, it is not limited to quartz fiber.

Further, the scope of application of the present invention is not limited to etching equipment, but can be applied to any equipment that generates plasma and observes its light emission.

〔Effect of the invention〕

According to the present invention, since it is possible to prevent reaction products from adhering to the plasma light collecting section, there is an effect that the reliability of monitoring the processing status in plasma processing can be improved.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing a plasma processing apparatus that is an embodiment of the present invention, FIG. 2 is a detailed view of section A in FIG. 1, and FIG. 3 is a second embodiment of the invention. Detailed view, FIG. 4 is a detailed view showing a third embodiment of the second factor. 5...Gas supply piping, 9...Quartz fine I, 10...Emission analysis bag Kt, 13...
...Processing room, 14...Daylighting Figure 1

Claims (1)

[Claims] 1. A processing chamber that is supplied with a processing gas and is evacuated to a predetermined pressure, a plasma generation means that generates plasma in the processing chamber, and a plasma emission detection means that detects the emission of the plasma; A plasma processing apparatus characterized in that a gas supply path for passing gas is connected to a lighting section provided in the chamber and for introducing plasma light into the plasma emission detection means.