JPH0653173A - Plasma processor having plasma heating mechanism - Google Patents

Abstract

PURPOSE:To enable high-speed plasma processing with a high-density plasma generated by providing a plasma heating mechanism separately from a plasma- generating microwave generator and a plasma-generating magnetic field generator. CONSTITUTION:A processing chamber 1 is inside a magnetic field region generated by coils 3, 4. Microwaves emitted from a magnetron 5 propagate through waveguides 6a, 6b, pass through a quartz window 2, and enter the processing chamber 1. The coil 3 has a DC power source connected to generate a stationary field, and a plasma is generated in the processing chamber 1 by interaction with microwaves. On the other hand, the coil 4 has an AC power source or a high frequency power source connected to generate an alternating field. Thus, the plasma is Joule-heated to generate high-density plasma. Therefore, a high- speed plasma processing is possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus.

[0002]

2. Description of the Related Art A conventional plasma processing apparatus is composed of a microwave generating device for plasma generation and a magnetic field generating device for plasma generation, as described in Japanese Patent Publication No. 53-34461.

[0003]

The above-mentioned prior art has a drawback in that it is not possible to perform high-speed plasma processing because no consideration has been given to increasing the density of generated plasma.

An object of the present invention is to provide a microwave plasma processing apparatus capable of high-speed plasma processing by generating high-density plasma by providing a function capable of additionally heating the generated plasma.

[0005]

In order to achieve the above object, a plasma heating mechanism is separately provided in addition to a microwave generator for plasma generation and a magnetic field generator for plasma generation. As the plasma heating mechanism, Joule heating, electromagnetic wave heating, beam heating or adiabatic compression heating is used.

[0006]

The plasma heating mechanism using Joule heating, electromagnetic wave heating, beam heating, or adiabatic compression heating, which is separately provided in addition to the microwave generating device for plasma generation and the magnetic field generating device for plasma generation, produces the generated plasma. Acts as additional heating. Thereby,
High-density plasma is generated and high-speed plasma processing becomes possible.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 shows a magnetic field microwave dry etching apparatus which is an embodiment of the present invention. In FIG.
Processing chamber 1 partitioned by container 1a, container 1b and quartz window 2
After decompressing the inside of the with a vacuum exhaust device (not shown),
An etching gas is introduced into the processing chamber 1 by a gas supply device (not shown), and the inside of the processing chamber 1 is adjusted to a desired pressure.
The processing chamber 1 is in the magnetic field region generated by the coils 3 and 4. Microwaves of, for example, 2.45 GHz emitted from the magnetron 5 are guided by the waveguides 6a and 6b.
The light propagates through the inside, passes through the quartz window 2, and enters the processing chamber 1. The material 8 placed on the sample table 7 is etched by the plasma generated by the microwave. Further, in order to control the etching shape of the material 8 to be processed, a high frequency power source 10 is connected to the sample stage 7 via a matching unit 9 and a high frequency voltage is applied.

In the case of this embodiment, a direct current power supply is connected to the coil 3, a stationary magnetic field is generated, and a plasma is generated in the processing chamber 1 by the interaction with the microwave.
On the other hand, an AC power supply or a high frequency power supply is connected to the coil 4 to generate an alternating magnetic field. Therefore, an alternating current flows in the plasma generated in the processing chamber 1 so as to cancel the alternating magnetic field. That is, the alternating magnetic field causes the plasma to be Joule-heated to generate high-density plasma.

According to the present embodiment, since the plasma can be heated, there is an effect that high density plasma is generated and high speed plasma processing becomes possible.

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the dome-shaped quartz bell jar 11 is used.
The processing chamber 1 is composed of the container 1a and the container 1a. In the case of the present embodiment, the coil 4 for Joule heating is arranged on the outer circumference of the waveguide 6d arranged on the outer circumference of the dome-shaped quartz bell jar 11. According to this embodiment, the same effect as that of the first embodiment is obtained.

Next, a third embodiment of the present invention will be described with reference to FIGS. In this embodiment, the magnetic field is generated by the coil 3 and the coil 12, and the waveform of the current flowing through the coil 12 is shown in FIG. That is, a current in which a direct current component and an alternating current component are superimposed flows through the coil 12, and a magnetic field in which a stationary magnetic field and an alternating magnetic field are superimposed is generated. Therefore, the plasma is Joule heated, and high-density plasma is generated. According to the present embodiment, in addition to the effect of the first embodiment, the coil can be made small, so that there is an effect that the entire apparatus can be downsized.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In this embodiment, the coil 13 is provided inside the waveguide 6d and on the outer circumference of the dome-shaped quartz bell jar 11. A high frequency power supply 15 is connected to the coil 13 via a matching unit 14. The plasma generated in the processing chamber 1 is heated by being irradiated with the electromagnetic wave emitted from the coil 13, and high density plasma is generated. According to this embodiment, the same effect as that of the first embodiment can be obtained.

Next, a fifth embodiment of the present invention will be described with reference to FIG. In this embodiment, the coil 13 for heating the electromagnetic field is provided in the processing chamber 1. According to this embodiment, the first
The same effect as the embodiment of

Next, a sixth embodiment of the present invention will be described with reference to FIG. In this embodiment, the loop antenna 16 is used to introduce an electromagnetic wave for plasma heating into the processing chamber 1. Although the loop antenna 16 is used in this embodiment,
Other dipole antennas or slot antennas may be used. In addition, introduce a wire into the plasma,
A so-called single probe may be used as the antenna. Moreover, you may use a grid as an antenna. Further, the rigid coil may be used as an antenna.
According to this embodiment, the same effect as that of the first embodiment can be obtained.

Next, a seventh embodiment of the present invention will be described with reference to FIG. In the present embodiment, the microwave generated by the microwave generator 17 is introduced into the processing chamber 1 through the waveguide 18 and the quartz window 19 to heat the plasma and generate high-density plasma. According to this embodiment, the same effect as that of the first embodiment can be obtained.

As described above, in the fourth to seventh embodiments, the example of electromagnetic wave heating is shown. The frequency of the electromagnetic wave used for heating is the type of electromagnetic wave heating, that is, electron cyclotron resonance heating, ion cyclotron resonance heating, and low frequency. It is determined by the mixed-wave heating, the Alfven wave heating, the traveling time magnetic pump heating, etc., and it is desirable that the transmission system of the electromagnetic wave and the shape of the antenna or coil are also determined according to the frequency of the electromagnetic wave.

Next, an eighth embodiment of the present invention will be described with reference to FIG. In this embodiment, an electrode 20 is provided in the processing chamber 1, and a high frequency power source 22 is connected to the electrode 20 via a matching device 21. When a high frequency voltage is applied to the electrode 20, an ion sheath is formed on the surface of the electrode 20 in contact with plasma. Ions are accelerated by the electric field in the ion sheath, collide with the electrode 20, and emit secondary electrons.
The secondary electrons are accelerated by the ion sheath and enter the plasma. That is, the plasma is heated by the electron beam emitted from the electrode 20, and high-density plasma is generated. In the case of the present embodiment, the effect of so-called magnetron discharge is added due to the interaction between the axial magnetic field generated by the coil 3 and the radial electric field in the ion sheath, so that a higher density plasma is generated. You can

According to this embodiment, the same effect as that of the first embodiment can be obtained. Further, by providing a quartz cylinder on the inner surface of the electrode 20, it is possible to prevent heavy metal ions from being mixed into the plasma. Further, when an insulator such as quartz is not provided on the inner surface of the electrode 20, the electron beam can be supplied into the plasma by connecting a DC power supply to the electrode 20 and applying a negative bias voltage. The same effect as that of the eighth embodiment can be obtained.

Next, a ninth embodiment of the present invention will be described with reference to FIG. In the present embodiment, an electron beam supply device 23 having a differential evacuation device and comprising a filament and a grid for acceleration or the like is connected to the processing chamber 1, and an electron beam emitted from the electron beam supply device 23 is supplied into the processing chamber 1. High-density plasma is generated by injecting into the plasma and heating the plasma.

In this embodiment, the same effect as that of the first embodiment can be obtained. In the ninth embodiment, an ion beam supply device is attached instead of the electron beam supply device 23, and the plasma is heated by injecting the ion beam into the plasma in the processing chamber 1, which is the same as in the ninth embodiment. The effect can be obtained. Further, in the ninth embodiment, a neutral particle beam supply device is attached instead of the electron beam supply device 23,
Even if the plasma is heated by injecting the neutral particle beam into the plasma in the processing chamber 1, the same effect as the ninth embodiment can be obtained.

Further, in FIG. 3, the plasma can be heated by the so-called adiabatic compression, in which the volume of the plasma is reduced by suddenly applying a large current to the coil 3 to generate a strong magnetic field. The same effect as that of the embodiment can be obtained.

Although the magnetic field dry etching apparatus has been described in each of the above-mentioned embodiments, other plasma processing apparatuses such as a dry etching apparatus utilizing a microwave, a plasma CVD apparatus, an ashing apparatus, etc.
The same effect can be obtained.

[0024]

According to the present invention, since the generated plasma can be additionally heated, a high-density plasma is generated and high-speed plasma processing can be performed.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a second embodiment of the present invention.

FIG. 3 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a third embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a time change of a current flowing through a coil 12 according to a third embodiment of the present invention.

FIG. 5 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a fourth embodiment of the present invention.

FIG. 6 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a fifth embodiment of the present invention.

FIG. 7 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a sixth embodiment of the present invention.

FIG. 8 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a seventh embodiment of the present invention.

FIG. 9 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to an eighth embodiment of the present invention.

FIG. 10 is a vertical sectional view of a processing chamber portion of a magnetic field microwave dry etching apparatus according to a ninth embodiment of the present invention.

[Explanation of Codes] 1 ... Processing chamber, 2, 19 ... Quartz window, 3, 4, 12, 13 ...
Coil, 5 ... Magnetron, 6, 18 ... Waveguide, 7 ... Sample stage, 8 ... Processed material, 9, 14, 21 ... Matching device, 10,
15, 22 ... High frequency power source, 11 ... Quartz bell jar, 16 ...
Loop antenna, 17 ... Microwave generator, 20 ... Electrode.

Claims (5)

[Claims] 1. A microwave plasma processing apparatus comprising a plasma generating apparatus using microwaves, a decompressible processing chamber, a gas supply apparatus, and a vacuum exhaust apparatus, wherein a plasma heating mechanism is provided. apparatus. 2. The plasma processing apparatus according to claim 1, wherein the plasma heating mechanism is Joule heating. 3. The plasma processing apparatus according to claim 1, wherein the plasma heating mechanism is electromagnetic field heating. 4. The plasma processing apparatus according to claim 1, wherein the plasma heating mechanism is beam heating. 5. The plasma processing apparatus according to claim 1, wherein the plasma heating mechanism is adiabatic compression heating.