JP3574373B2 - Plasma processing apparatus and plasma processing method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a plasma processing apparatus and a plasma processing method used for forming and etching a thin film such as a semiconductor device, an electrophotographic photosensitive member, an image sensing device, and a photovoltaic device.
[0002]
[Prior art]
The configuration of a conventional processing apparatus using plasma will be described below with reference to the drawings, taking a plasma CVD apparatus applied to forming a thin film of amorphous silicon (hereinafter a-Si) as an example.
[0003]
FIG. 6 shows a schematic view of the apparatus, in which a high-frequency electrode 51 and a substrate holder 53 provided with a substrate heating heater are arranged in parallel in a reaction vessel 50. A high-frequency power supply 54 is connected to the high-frequency electrode 51, and high-frequency power of, for example, 13.56 MHz is supplied. The substrate holder 53 is grounded together with the reaction container 50 and serves as a counter electrode. Thus, glow discharge plasma is generated between the high-frequency electrode 51 and the substrate holder 53. For example, a mixed gas of monosilane and hydrogen is supplied into the reaction vessel 50 through a reaction gas supply pipe 55, and the gas in the reaction vessel 50 is exhausted through an exhaust pipe 56. The substrate 52 is held on the substrate holder 53 and heated to a predetermined temperature.
[0004]
Next, the operation of this device will be described.
[0005]
First, after the inside of the reaction vessel 50 is evacuated by driving a vacuum pump (not shown), for example, monosilane and hydrogen are supplied through the reaction gas supply pipe 55. When a voltage is applied to the high-frequency electrode 51 from the high-frequency power supply 54 while maintaining the pressure in the reaction vessel 50 at 0.05 to 0.1 Torr, a glow discharge plasma is generated between the high-frequency electrode 51 and the substrate holder 53, and the reaction gas is generated. Among the gases supplied from the supply pipe 55, the monosilane gas is decomposed by the glow discharge plasma. Then, radicals containing Si are generated and adhere to the surface of the substrate 52 to form an a-Si thin film.
[0006]
In such a film forming method using a conventional apparatus, it is generally known that quality is deteriorated by high-speed film forming. Therefore, at present, in order to realize high-speed film formation without deteriorating the film quality, plasma conditions (frequency, power, driving waveform), gas conditions (partial pressure, flow rate, added gas type, impurity concentration), temperature conditions Investigations have been made on optimization such as the above, and the effectiveness of the VHF band of about 100 MHz is being clarified with respect to the frequency of plasma generation. With respect to the effectiveness of the VHF band, it is understood that the plasma density increases under the condition that the energy of electrons and ions is smaller than 13.56 MHz, so that high-speed film formation can be performed without deteriorating the film quality.
[0007]
However, when the above-described apparatus and plasma conditions are applied to a large-area film formation required for a solar cell, a liquid crystal display element, or the like, a large distribution of film thickness and film quality that cannot be ignored is generated. This is because when an AC power is applied, a standing wave is generated in the process of the current propagating through the electrode, and the wavelength of the electromagnetic wave becomes shorter as the plasma frequency becomes higher. It is considered that the standing wave cannot be ignored. Even if the electric field distribution before plasma generation by this standing wave is about 1%, it contributes to plasma density and plasma temperature during plasma generation, resulting in a processing distribution ranging from tens to several tens%. Sometimes.
[0008]
A method for improving this point is disclosed in, for example, Japanese Patent Application Laid-Open No. H11-243062. An example of this device will be described with reference to FIG.
[0009]
FIG. 7 is a schematic view of the apparatus, in which a substrate holder 63 for mounting a cylindrical substrate 62 having a diameter of 108 mm and a length of 358 mm on which a film is to be formed is placed at the center of a reaction vessel 60 composed of divided dielectric members. Is provided. A rod-shaped high-frequency electrode 61 having a diameter of 20 mm and a length of 450 mm is provided outside the reaction vessel 60 at the center of the plasma generation region, and high-frequency power is generated by the high-frequency power supply 64 and passed through the matching circuit 680. It is divided and supplied to one end of the high-frequency electrode 61 via the auxiliary matching circuit 681, and is grounded via the phase adjustment circuit 682 at the opposite end. The gas is supplied by gas supply means 65 including a gas cylinder, a mass flow controller, a valve, and the like, and the gas is exhausted by vacuum exhaust means 66 having a vacuum pump via an exhaust pipe having an exhaust valve. Note that this device has a cylindrical shape with the central axis as the target, and four high-frequency electrodes 61 and the like are provided at four axially symmetric positions.
[0010]
According to Japanese Patent Application Laid-Open No. 11-243062, in this device, the SiH₄The gas is introduced into the reaction vessel 60 at 500 sccm, the pressure is adjusted to 10 mTorr, the film is formed while rotating the substrate, and high-frequency power of, for example, 100 MHz and 1 kW is generated, and divided into four through a matching circuit 680. When the phase adjustment circuit 682 is removed and the high-frequency electrode 61 is released when the high-frequency electrode 61 is released evenly through the auxiliary matching circuit 681, the deposition rate is 5.7 nm / s and the deposition rate distribution is While the light sensitivity variation was large by 24%, the high-frequency electrode 61 of one set of four phase adjustment circuits 682 opposed to each other was short-circuited directly to the ground inside the reaction vessel 60, The remaining opposing pair is not connected to the ground, but is set at almost the open end of only the stray capacitance in the phase adjustment circuit 682, so that the film forming speed is 6.4 nm / s and the film forming speed is Fabric 4% in light sensitivity variation small, and good results have been obtained. Under these improved plasma conditions, the ends of adjacent high-frequency electrodes are opened and short-circuited to reverse the phase of the standing wave, and cancel the electric field distribution to reduce the deposition rate and film quality distribution. I have.
[0011]
In the apparatus proposed in Japanese Utility Model Application Laid-Open No. 37919/1987, the film-forming speed distribution is reduced by optimizing the structure of the opposing electrode to a convex shape.
[0012]
[Problems to be solved by the invention]
In the apparatus proposed in Japanese Patent Application Laid-Open No. H11-243062 described above, it is possible to increase the deposition rate over a large area while suppressing the deterioration of the film quality and its distribution and the film thickness distribution. Since a high-frequency electrode to be lined is required, and a plurality of power supply devices are required, the device becomes complicated. Further, when the high-frequency electrode is not a line object, the control of the phase adjustment becomes complicated.
[0013]
Further, in the apparatus proposed in Japanese Utility Model Laid-Open Publication No. 62-37919, there is no description about a method of processing an electrode into the above-described shape. For example, although it is possible to process by machining, etc., it is necessary to predict in advance what shape should be processed, that is, the distribution shape of the standing wave formed on the electrode and the plasma energy It is extremely difficult to accurately determine the distribution by calculation, and optimizing the processing shape while actually forming a film requires a great deal of trial and error. Further, it is necessary to prepare a new electrode every time the film forming conditions are different.
[0014]
As described above, the plasma CVD apparatus has been described. For example, in a plasma etching apparatus, when the processing rate is increased, the film quality is deteriorated due to ion damage or the like, and when the power supply frequency is increased as one method for improving the film quality. The same problem is encountered in the processing rate distribution.
[0015]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and a plasma CVD apparatus or a processing rate distribution capable of forming a high-quality thin film at a high speed and a large area with a small film quality and a small film thickness distribution. It is an object of the present invention to provide a plasma processing apparatus and a plasma processing method which are used in a plasma etching apparatus or the like capable of performing etching in a small area at a high speed and with a large area.
[0016]
[Means for Solving the Problems]
The plasma processing apparatus according to the present invention includes a high-frequency electrode and a counter electrode,The reaction gas is supplied and the high-frequency power is supplied to the high-frequency electrode, so that the high-frequency electrode and the counter electrode are disposed between the high-frequency electrode and the counter electrode.The above reaction gasTo generate plasma insidePlacedIn a plasma processing apparatus that performs plasma processing on a substrate,At least one of the high-frequency electrode and the counter electrode is formed by the plasma of the electrode etching gas formed between the high-frequency electrode and the counter electrode, and in the entire surface facing the plasma of the electrode etching gas. Etching is performed until the etching rates are substantially the same.
[0017]
Preferably, in the above invention, at least one of the high-frequency electrode and the counter electrode has at least a surface facing the plasma made of molybdenum.
[0018]
In the above invention, preferably,High frequency electrode andthe aboveWhat is a counter electrode?Short-circuited.
[0019]
A plasma processing method according to the present invention includes a high-frequency electrode and a counter electrode.Plasma processing equipmentInsideBy supplying a high-frequency power to the high-frequency electrode while supplying a reaction gas to the high-frequency electrode and the counter electrode,The above reaction gas plasmaGeneratePlaced insideIn a plasma processing method for performing plasma processing on a substrate,While introducing an electrode etching gas into the inside of the plasma processing apparatus, a plasma of the electrode etching gas is generated between the high-frequency electrode and the counter electrode, and etching is performed on the entire surface facing the plasma. An electrode etched until the rates are substantially the same is used as at least one of the high-frequency electrode and the counter electrode.
[0021]
In the above invention, preferably, the electrode etching gas is introduced.During etching of plasma generating electrodethe aboveHigh frequency electrode andthe aboveCounter electrodeWithinterval,the aboveHigh frequency power supplied to the high frequency electrode, andthe abovePressure of gas supplied to plasma processing equipmentTo,Introducing the above reaction gas to the above substratePlasma treatmentDoEdgeMake them the same.
[0022]
Preferably, in the above invention, a dummy substrate is arranged inside the plasma processing apparatus when the plasma generating electrode into which the electrode etching gas is introduced is etched.
[0023]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a plasma processing method and a plasma processing apparatus of the present invention will be described with reference to the drawings.
[0024]
<Embodiment 1>
FIG. 1 is a sectional view of a plasma processing apparatus according to Embodiment 1 of the present invention. In FIG. 1, a high-frequency electrode 11 is supported in a reaction vessel 10 by an insulating electrode support member (not shown), and a substrate holder 13 movable in parallel with the high-frequency electrode 11 is arranged. A water passage (not shown) through which cooling water for cooling passes is provided inside the high-frequency electrode 11, and cooling water is supplied and circulated from outside the reaction vessel 10. The substrate holder 13 has a heater 19 inside and a vacuum chuck groove on the upper surface, and is mounted on a table 17 movable in the left and right directions by an X stage 171 and in the vertical direction by a Y stage 172. The gap between the high-frequency electrode 11 and the substrate 12 placed on the substrate holder 13 can be adjusted to several mm or less. One end of the high-frequency electrode 11 is connected to a high-frequency power supply 14 via an impedance matching section 141 and a power supply member 142 to supply high-frequency power. The substrate holder 13 is grounded together with the reaction vessel 10 and serves as a counter electrode. A reaction gas supply pipe 15 and an exhaust pipe 16 are inserted into the reaction vessel 10, and the reaction gas is supplied to the vicinity of the high-frequency electrode 11 through the reaction gas supply path 151, The gas is exhausted from the vicinity through the reaction gas discharge path 161 and further through the exhaust pipe 16.
[0025]
The principle of the electrode processing method in this device will be described.
[0026]
(Step 1)
First, an electrode for plasma generation (before processing) as shown in FIG. 2 is installed in the above-described plasma processing apparatus as a high-frequency electrode 11. Note that the direction indicated by the arrow P in FIG. 2 corresponds to the direction penetrating the paper of FIG. That is, the direction perpendicular to the scanning direction (the Q direction in the figure) of the substrate 12 is shown. Before processing, the surface of the high-frequency electrode 11 facing the substrate is parallel to the counter electrode (substrate holder 13) or the substrate 12.
[0027]
(Step 2)
A dummy substrate is provided in the apparatus shown in FIG. 1, and a gas capable of etching an electrode is supplied to the high-frequency electrode section through a reaction gas supply pipe 15 and a reaction gas supply path 151. 11 is applied with a high-frequency voltage. As a result, glow discharge plasma is generated between the high-frequency electrode 11 and the substrate holder 13, the reaction gas is decomposed, and some of the generated radicals combine with the atoms of the high-frequency electrode 11 and exit into the gas. That is, the high-frequency electrode 11 is etched.
[0028]
In this step 2, the high-frequency electrode 11 is used until the etching rates at the respective portions (for example, points A, B, and C in FIG. 2) of the plasma generation region (the surface facing the plasma region) in the high-frequency electrode 11 become substantially the same. Processing is performed (this point will be described in detail below with reference to FIG. 3). More specifically, the etching is performed for a period of time at which the etching rate obtained in advance by experiments or the like becomes substantially the same, or the processing state of the high-frequency electrode 11 is monitored. The etching may be performed until the etching rates become substantially the same.
[0029]
(Step 3)
Subsequent to the processing of the electrodes, after sufficiently baking and evacuating the reaction vessel 10, a substrate 12 to be subjected to plasma processing is provided, and the substrate 12 is subjected to desired plasma processing. That is, by supplying a gas capable of performing a desired plasma process to the high-frequency electrode unit through the reaction gas supply pipe 15 and the reaction gas supply path 151 and applying a high-frequency voltage to the high-frequency electrode 11, Glow discharge plasma is generated between the substrate 11 and the substrate holder 13, and the substrate 12 is subjected to plasma processing.
[0030]
Once the high-frequency electrode 11 has been processed in Step 2, it is possible to continuously perform the plasma processing in Step 3 without executing Step 2.
[0031]
In the plasma processing method of the present invention, as described in steps 1 to 3 above, after processing the high-frequency electrode until the etching rate of the plasma generation region in the high-frequency electrode 11 becomes substantially the same, the desired plasma processing is performed on the substrate. Execute. Thereby, uniform plasma processing can be realized. This principle will be described in detail below.
[0032]
In step 2 described above, the high-frequency electrode 11 is etched. FIG. 3 (a) shows the time change of the etching rate at points A, B and C in FIG. 2 during the etching. As shown in this figure, immediately after the discharge, the plasma energy distribution is uneven due to the influence of the standing wave and the like, and the etching rate varies at each position. However, as time elapses, the processing rates at each point become closer and eventually become substantially the same.
[0033]
FIG. 3B is a view showing the shape in the electrode longitudinal direction (the direction of arrow P in FIG. 2). Α, β, and γ in FIG. 3B have different processing times, and the processing times are longer in the order of α, β, and γ. The machining amount on the vertical axis is an arbitrary unit and indicates a displacement amount from the reference point on the left end, and the dotted line indicates the position of the electrode end surface before machining. Here, from α to β, a part of the plasma generation region of the processing electrode 11 is particularly deeply etched to greatly change the shape of the surface, but the change of the surface shape is small (similarly changed) in β and γ. . That is, the difference between the processing rates at the end and the center is small. In the example of FIG. 3, the etching shape is concave with respect to the substrate surface, but may be convex depending on the configuration of the plasma reactor, and the shape of the electrode is not limited.
[0034]
The above phenomenon can be explained as follows. Before the etching, the electrode surface is flat, but an electric field distribution is formed in the middle in the axial direction. After the start of etching, the plasma rate (electron density and electron temperature) in the central portion is large, so that the etching rate is large. As the etching progresses, the gap becomes larger and the electric field weakens in the portion where the etching has progressed, so that the plasma energy decreases and the etching rate decreases. Due to such a self-control effect, the etching rate distribution eventually disappears.
[0035]
At the stage where the distribution of the etching rate disappears, the electric field distribution in the plasma space is offset by the voltage distribution due to the standing wave and the discharge gap distribution due to the electrode shape, resulting in an electrode having a very small plasma energy distribution. It is thought that it is. Therefore, when plasma processing is performed in this state, uniform plasma processing without distribution can be realized.
[0036]
Since the present invention is based on the principle described above, it is desirable that the processing of the high-frequency electrode 11 in step 2 and the plasma processing in step 3 be performed under the same conditions. That is, it is desirable that the gap between the high-frequency electrode 11 and the counter electrode (substrate holder 13), the high-frequency power, and the pressure of the gas introduced into the device are the same. Also, in order to make the plasma conditions the same, it is desirable that the substrate (dummy substrate) be placed as described above even when the high-frequency electrode 11 is etched. Of course, it is desirable that the material and shape of the dummy substrate and the substrate 12 be the same.
[0037]
Hereinafter, specific examples will be described.
[0038]
(Example 1)
A specific example in which film formation is performed by using the above-described apparatus will be described in the order of (1) processing (pre-processing) of a high-frequency electrode and (2) film formation.
[0039]
(1) Processing of high-frequency electrode (pre-processing)
An aluminum high-frequency electrode 11 having a shaft length of 1 m (in the direction of the arrow P in the figure) and a width of 50 mm as shown in FIG. 2 was used, and a quartz glass dummy substrate was arranged at a position where the gap with the high-frequency electrode 11 was 300 μm. Then, by driving a vacuum pump (not shown), the inside of the reaction^-7After evacuation to about Torr, a mixed gas of carbon tetrachloride, boron chloride and helium was supplied while being adjusted to 1 atm. Next, high-frequency power of a frequency of 144 MHz and 5 kW was supplied, and the high-frequency electrode 11 was processed while supplying a reaction gas of 2% of carbon tetrachloride and 0.2% of boron chloride at 300 slm.
[0040]
When the processing time of the high-frequency electrode 11 was changed to 4 minutes, 8 minutes, and 12 minutes, when the processing time increased from 4 minutes to 8 minutes, the shape of the plasma generation region (the surface facing the plasma region) changed significantly. However, the change in shape was slight even when the time was increased from 8 minutes to 12 minutes. The processing shape in FIG. 3B used in the above description shows the processing shape in the present embodiment, and α, β, and γ correspond to the processing shapes at the processing times of 4, 8, and 12 minutes, respectively. I have. Using a laser type dimension measuring device, the distance from the substrate to the electrode end face at each position in the axial direction was measured, and the processing speed near the axis center was calculated from the relationship between the processing shape and the etching time. , Β, and γ in the order of 10 μm / min, 7 μm / min, and 6 μm / min (processing amount / processing time). Therefore, at the stage of processing for 12 minutes, the etching rate was 6 μm / min (processing amount / processing time) in the entire plasma generation region of the high-frequency electrode 11.
[0041]
In the present embodiment, the processing (etching of the high-frequency electrode 11) is performed at 1 atm or lower to obtain a high processing speed. However, the present invention is not limited to this condition, and several m to several hundreds generally applied are used. It may be performed under a pressure of the order of mTorr. Of course, as described above, it is more preferable to perform the processing under the same plasma conditions as when performing the plasma processing.
[0042]
Further, the etching gas for aluminum is CCl used above.₄Besides BCl₃, CCl₂F₂, SiCl₄Such as Cl-based gas and Br₂, BBr₃And the like can be used.
[0043]
(2) Film formation
Subsequent to the processing of the high-frequency electrode 11, the reaction vessel 10 was sufficiently baked and evacuated, and then the following film forming process was performed using the apparatus shown in FIG.
[0044]
First, a sufficiently washed quartz glass substrate 12 was placed on a substrate holder 13. Then, the table 17 was raised to a position where the substrate 12 and the high-frequency electrode 11 became a predetermined gap, and the heater 19 was used to heat the substrate 12 to a desired temperature (200 ° C.). Next, the reaction vessel 10 is purged with helium until the atmospheric pressure becomes about 1 atm, and the reaction gas (monosilane 0.1-0.5%, hydrogen 1-5 % Helium gas) was supplied while adjusting to 1 atm. In practice, it is desirable to set the pressure slightly lower than 1 atm for safety in preventing gas leakage.
[0045]
Here, a high-frequency voltage (input power: 144 MHz, 1.5 to 7 kW) is applied from the high-frequency power supply 14 to the high-frequency electrode 11 to generate glow discharge plasma between the high-frequency electrode 11 and the substrate holder 13. A thin film (a-silicon) was formed by decomposition by glow discharge plasma. The gas containing radicals and the like that has not been transported to the substrate surface is exhausted out of the chamber through the exhaust path 161 and the exhaust pipe 16, passes through a filter for removing particles, and is supplied again into the chamber.
[0046]
During film formation, the substrate holder 13 is moved in the direction of arrow Q (scan direction) in FIG. 1 at a substrate moving speed of 1 mm / s to form a thin film over the entire surface of the substrate 12 (800 mm × 600 mm). Thereafter, the table 17 was lowered and the electrode 11 was cooled while replacing the residual gas in the reaction vessel with nitrogen. After nitrogen replacement and cooling of the high-frequency electrode 11 and the substrate 12, the substrate 12 on which the thin film was formed was taken out.
[0047]
When the a-Si film having a thickness of 3500 ° to 5000 ° was formed in this manner, the film formation rate was 10 to 100 ° / s, and the film thickness distribution in the axial direction at the measurement points shown in FIG. ) Is 80 ° to 220 °, indicating that an a-Si film having a small film thickness distribution can be produced.
[0048]
(Comparative example)
In the above apparatus, a film was formed under the same conditions as above using a high-frequency electrode with a flat plasma generation surface that had not been subjected to pre-processing, and the film thickness distribution was at least 400 °.
[0049]
(Example 2)
In the processing process of the high-frequency electrode 11 shown in the first embodiment, the stage was not moved, but in the second embodiment, the same conditions as in the normal film forming process, that is, while the substrate was reciprocated at 1 mm / s. went.
[0050]
Using this electrode, an a-Si film was formed by the process described in Example 1. In the film formation from 3500 ° to 5000 ° over a range of 800 mm × 600 mm, the film formation rate was 10 ° to 100 ° / s, and the film formation rate was the same as in Example 1, but the film thickness distribution in the axial direction (axial direction) (One line is one set) was 50 ° to 180 °, and an a-Si film having a smaller distribution could be produced.
[0051]
<Embodiment 2>
Next, a plasma processing method and a plasma processing apparatus according to Embodiment 2 of the present invention will be described. However, in the present embodiment, the description of the same parts as in the first embodiment will be omitted or simplified.
[0052]
FIG. 5 is a diagram illustrating a configuration of a plasma processing apparatus according to the second embodiment. The differences from the plasma processing apparatus of FIG. 1 are as follows. That is, the high-frequency power source 14 is connected to one end of the high-frequency electrode 11 in the axial direction (P direction in the drawing) via the impedance matching unit 141 and the power supply member 142, and the opposite end is used as a counter electrode. In that it is connected to the substrate holder 13 via the short-circuit member 143.
[0053]
When the high-frequency electrode 11 was processed and formed into a film under the same conditions as in Example 1 using this plasma processing apparatus, the film thickness distribution was 70 to 150 °, which was smaller than that in Example 1.
[0054]
In the first embodiment as well, it was possible to form a film having a small film thickness distribution by using a pre-processed electrode in the same apparatus as the film forming apparatus. (In Example 1, the exceptional one was excluded, and the distribution range was described as 80 to 220 °).
[0055]
The inventor of the present application believes that this is because the end position of the standing wave (load viewed from the electrode end) has changed for some reason, and the distribution of the standing wave has changed from that during the pre-processing of the electrode. In the embodiment, in order to solve this problem, one end of the high-frequency electrode 11 and one end of the counter electrode are short-circuited. As a result, the terminal position is fixed as a short-circuited end, and the standing wave distribution is also fixed, so that the uniformized plasma energy distribution during electrode processing is stably reflected as it is on the film formation, resulting in a smaller film thickness distribution. Moreover, the effect was stabilized.
[0056]
In the embodiment of the present invention described above, a high-frequency electrode made of aluminum used in a normal plasma processing apparatus is used, but aluminum is a reaction product (aluminum chloride) when etched with carbon tetrachloride. However, because of low saturated vapor pressure, it is easy to form fine particles, which may cause contamination of the apparatus. Therefore, in Embodiments 1 and 2 described above, the reaction space is made smaller in the direction in which the reaction gas flows, and a gas exhaust path is provided from a location very close to the reaction space, so that the generated fine particles are kept in the apparatus. To prevent contamination of the equipment.
[0057]
In order to prevent contamination of the apparatus, for example, an electrode having a plasma generation region (surface facing the plasma) coated with molybdenum may be used as a high-frequency electrode to be pre-processed, and carbon tetrafluoride may be used as an etching gas. In this case, since the saturated vapor pressure of the reaction product (molybdenum fluoride) is high, precipitation of fine particles hardly occurs and contamination of the device can be prevented.
[0058]
Further, in the above embodiment, the processing of the high-frequency electrode is performed until the etching rate becomes substantially the same in the plasma generation region (the surface facing the generated plasma). If the etching is performed in the apparatus for performing the plasma processing, a certain effect can be obtained.
[0059]
Furthermore, although the case where the high-frequency electrode is processed has been described above, the present invention is not limited to this, and at least one of the counter electrode and the high-frequency electrode may be processed. However, when the substrate is mounted on an electrode (high-frequency electrode or counter electrode), it is preferable that the electrode on which the substrate is mounted is not processed.
[0060]
Further, the present invention is applicable not only to the above-described film formation using plasma but also to etching using plasma, and in this case, the uniformity of etching can be improved.
[0061]
Further, the plasma processing apparatus of the present invention is not limited to the configurations shown in FIGS. 1 and 5, but can be applied to various types of plasma processing apparatuses. For example, the present invention can be applied to a parallel plate type or shower electrode type plasma processing apparatus.
[0062]
【The invention's effect】
According to the plasma processing method and the plasma processing apparatus of the present invention, the plasma processing is performed using the high-frequency electrode etched in the apparatus prior to the plasma processing. Can be performed uniformly.
[0063]
In addition, by short-circuiting the high-frequency electrode and the counter electrode and fixing the terminus, the standing wave is fixed, and plasma processing with a small distribution can be performed stably.
[0064]
In addition, by coating at least the surface of the high-frequency electrode facing the plasma with molybdenum, deposition of fine particles hardly occurs during plasma processing after the processing, so that device contamination can be prevented.
[Brief description of the drawings]
FIG. 1 is a configuration diagram illustrating a plasma processing apparatus according to a first embodiment of the present invention.
FIG. 2 is a diagram showing an electrode shape of the plasma processing apparatus of FIG.
3A is a diagram showing a change in an etching rate of an electrode of the plasma processing apparatus of FIG. 1, and FIG. 3B is a diagram showing a shape change during processing.
FIG. 4 is a diagram showing measurement positions of a film thickness distribution.
FIG. 5 is a configuration diagram illustrating a plasma processing apparatus according to a second embodiment of the present invention.
FIG. 6 is a configuration diagram showing a conventional plasma CVD apparatus.
FIG. 7 is a configuration diagram showing another conventional plasma CVD apparatus.
[Explanation of symbols]
10 Reaction vessel
11 High frequency electrode
12 Substrate
13 Substrate holder
14 High frequency power supply
15 Reaction gas supply pipe
16 Reaction gas exhaust pipe
151 Reaction gas supply path
161 Reaction gas exhaust path
142 power supply member
143 short circuit member

Claims (3)

A high-frequency electrode and a counter electrode are provided, and the reaction gas is supplied and the high-frequency power is supplied to the high-frequency electrode, thereby generating a plasma of the reaction gas between the high-frequency electrode and the counter electrode. In a plasma processing apparatus for performing plasma processing on a substrate disposed therein,
At least one of the high-frequency electrode and the counter electrode is formed by a plasma of an electrode etching gas formed between the high-frequency electrode and the counter electrode, over the entire surface facing the plasma of the electrode etching gas. A plasma processing apparatus formed by etching until the etching rates are substantially the same . The plasma processing apparatus according to claim 1, wherein at least one of the high-frequency electrode and the counter electrode has at least a surface facing the plasma formed of molybdenum. By supplying a reaction gas and supplying high-frequency power to the high-frequency electrode inside the plasma processing apparatus including the high-frequency electrode and the counter electrode, the reaction gas is supplied between the high-frequency electrode and the counter electrode. In a plasma processing method of generating plasma and performing plasma processing on a substrate disposed therein,
  While introducing an electrode etching gas into the inside of the plasma processing apparatus, a plasma of the electrode etching gas is generated between the high-frequency electrode and the counter electrode, and etching is performed on the entire surface facing the plasma. A plasma processing method, wherein an electrode etched until the rates are substantially the same is used for at least one of the high-frequency electrode and the counter electrode.

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