JPH11307521A - Plasma cvd equipment and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide plasma CVD equipment which is able to restrain defects due to particles caused in a formed film, and is hardly damaged by cleaning and is high in productivity. SOLUTION: A lower electrode 2 housing a wafer 3 and an upper electrode 1 serving as a diffuser jetting reaction gas are installed. Around the upper electrode 1, an insulating ring 7 is installed. A heater auxiliary electrode 6, constituted of a metal plate including a heater is installed in a trench formed in the insulating ring 7. At film forming, the heater auxiliary electrode 6 is used as a heater, and insulator 7 is heated at a high temperature, so that the adhesion of an unnecessary film is made to increase and the film is made hard to peel. At cleaning, the heater auxiliary electrode 6 is used as an electrode for RF discharge and plasma is spread, so that the unnecessary film in that part is effectively eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma CV having high productivity and capable of suppressing defects generated in a film to be formed.
The present invention relates to a D film forming apparatus and a method of using the same.

[0002]

2. Description of the Related Art In recent years, there has been a remarkable progress in thin-film applied devices represented by LSIs, TFT liquid crystals, solar cells and the like, and accordingly, demands for thin-film manufacturing equipment used for the manufacture have become severe. I have. For example, there is a strong demand for reduction of particles necessary for realizing high integration and improvement of productivity for realizing low cost.

[0003] In order to meet these demands, it is necessary to remove particles caused by peeling of an unnecessary film adhered to the inner wall of the chamber during film formation to drop on a wafer to cause a defect in a device or to remove an unnecessary film. It is necessary to solve a problem such as a decrease in productivity caused by frequently performing the dry cleaning process during the operation.

[0004] The plasma CVD apparatus is a promising thin film device manufacturing apparatus excellent in high-speed film formation, low-temperature film formation, step coverage, adhesion, and the like.
The above issues need to be solved.

As a method for solving the problem, that is, a method for suppressing adhesion of an unnecessary film on the inner wall of the chamber or preventing peeling by strengthening the adhesion, a method of performing heating has been proposed. These range from large-scale heating of the entire chamber to a high temperature, to heating of the entire upper chamber and the upper electrode locally, but heating is effective only with the upper electrode above the wafer and the upper surface of the chamber. .

[0006] Further, a technique for solving the problem of
As a method for increasing the efficiency of dry cleaning, a method has been proposed in which an auxiliary electrode is provided to change the shape of plasma to remove an unnecessary film in a place where removal is difficult.

Hereinafter, specific examples thereof will be described.
FIG. 5 shows a plasma CVD method described in Japanese Patent Application Laid-Open No. 2-39422 in which a deposition plate heated by a heater is provided near the upper electrode.
Device. In FIG. 5, a chamber lid 25 is covered on the film forming chamber 24, thereby forming a vacuum container. A lower electrode 22 having a built-in heater is provided in the chamber 24. Wafer 2
3 is placed on the lower electrode 22 and heated by the heater.

Above the lower electrode 22, the upper electrode 21 is attached to the chamber lid 25 via an insulator 33. The upper electrode 21 is separated from the chamber lid 25 by the insulator 33.
And the insulating plate 37 is electrically insulated. Upper electrode 21
There is a plate 37 for preventing unnecessary film on the upper surface of the chamber, and the plate 37 can be heated by the heater 34. The heater 34 is a heater switch (heater SW) 36
Is connected to the heater power supply 35 via the. The upper electrode 21 can introduce a gas from the gas introduction port 28 and supply the gas toward the wafer 23 in a shower shape. Gas inlet 2
Although not shown, a supply device for supplying a material gas for film formation and an etching gas for dry cleaning is connected to the end of 8. The gas supplied to the chamber 24 is
More exhausted. Although not shown, an exhaust unit such as a vacuum pump and a pressure control unit for keeping the pressure in the chamber constant are provided at the end of the exhaust port 29. Chamber 24,
The chamber lid 25, the deposition-preventing plate 37, and the lower electrode 22 are grounded, and the upper electrode 21 is connected to an RF electrode 30 via an RF-switch (RF-SW) 31.

In the plasma CVD apparatus shown in FIG. 5, a film is formed by the following film forming process.

First, the heater SW 36 is turned on, and the deposition prevention plate 37 is heated by the heater 34. Next, the wafer 23 is mounted on the lower electrode 22, and is heated by the built-in heater of the lower electrode 22.

A material gas is introduced from the upper electrode 21, the pressure in the chamber is adjusted, the RF-SW 31 is turned on, RF power is applied between the upper and lower electrodes, and plasma is generated. Then, a thin film is formed by the reaction of the material gas atoms obtained by the plasma on the wafer 23.

In such a film forming process, the reaction of the material gas atoms occurs not only on the wafer 23 but also on the chamber 24.
Also occurs on the side surface, bottom surface, and the surface of the attachment-preventing plate 37. For this reason,
Unnecessary films are formed at those sites. Among these unnecessary films, those that adhere to the surface of the deposition-preventing plate 37 become difficult to be easily peeled off because the deposition-preventing plate 37 is heated to a high temperature and the adhesive force is increased, but it is difficult to peel off. The unnecessary film attached to the substrate has a low temperature and becomes an unreacted film and is easily peeled off. The unnecessary film grows by repeating the film formation, and thus peels off and becomes particles, and the wafer 2
3 and may cause a defect.

In the plasma CVD apparatus shown in FIG.
The unnecessary film on the upper surface of the chamber, which is likely to fall on the upper surface 3, is made harder to fall by the anti-adhesion plate. However, if the film formation is repeated many times, the thickness of the unnecessary film on the deposition-preventing plate increases, and eventually the film is peeled off. To prevent this, dry cleaning is usually performed when the unnecessary film is properly attached.

Hereinafter, the dry cleaning process will be described. In the dry cleaning process, the upper electrode 2 is placed in a state where the wafer 23 is not placed on the lower electrode 22.
An etching gas is introduced from Step 1. Then, in a state where the pressure in the chamber is adjusted, the RF-SW 31 is turned on, RF power is applied, and plasma is generated between the upper and lower electrodes. When the etching gas atoms obtained by the plasma collide with the upper electrode 21, the lower electrode 22, and the periphery thereof, the unnecessary film attached thereto is decomposed, vaporized and removed.

FIG. 6 is a view for explaining another example of a conventional plasma CVD apparatus (see Japanese Patent Application Laid-Open No. 4-99281). The plasma CVD apparatus of FIG.
The difference from the apparatus is that an auxiliary electrode 26 is provided in the chamber.

The auxiliary electrode 26 is supported by a mounting rod 38 so as to surround the space between the upper and lower electrodes in the shape of a washer. The tip of the rod 38 is supported by a straight introducer 39 to enable the auxiliary electrode 26 to move up and down. The rectilinear introduction device 39 is fixed to an insulator 34 provided on a part of the bottom surface of the chamber 24. Thereby, the straight introduction device 39, the rod 38, and the auxiliary electrode 26 are connected to the chamber 2
4 and insulated. The straight-introducing device 39 includes an RF-SW 32
The RF power supply 30 is connected via the.

In such a plasma CVD apparatus, a film forming process is performed by a process similar to the above-described film forming process. At this time, in the film forming process, the auxiliary electrode 26 is disposed at a position lower than the lower electrode so as not to disturb the plasma due to abnormal discharge or the like. That is, the auxiliary electrode 26 has no relation to the film formation.

In the dry cleaning process, a process similar to the above-described dry cleaning process shown in FIG. That is, first, RF is applied between the upper and lower electrodes. Thereafter, the RF-SW 31 is turned off, and the auxiliary electrode 26 is moved to an appropriate position. Then, the RF-SW 32 is turned on, and discharge is performed between the auxiliary electrode 26 and the side surface of the lower electrode 22, the auxiliary electrode 26 and the side wall of the chamber 24, the auxiliary electrode 26 and the chamber cover 25, and the like.
Unnecessary films on the side walls of the chamber and around the insulator 33, which are difficult to remove by the dry cleaning in the former stage, can be easily removed.

[0019]

According to the plasma CVD apparatus shown in FIG. 5, since the adhesion of the unnecessary film is strengthened, the amount of particles generated at the time of film formation is reduced.
The required period of the dry cleaning step (the number of sheets that can be subjected to the continuous film forming process) increases.

However, since the deposition-preventing plate needs to be set at a distance larger than the distance between the upper and lower electrodes so as not to disturb the discharge during film formation, even if dry cleaning is performed, the plasma hardly reaches the deposition-preventing plate. The etching amount is smaller than that around the upper and lower electrodes. In addition, since the film is heated at the time of film formation to enhance the adhesion of the film, it takes a very long cleaning time to cleanly remove the film. If the cleaning time is lengthened, the surface of the upper and lower electrodes from which the film has been removed in a short time will continue to be hit with plasma, damaging the electrode surface, accelerating the cycle of component replacement, increasing replacement component cost and maintenance cost. The evil comes out. If dry cleaning is terminated in a state where the deposition-preventing plate cannot be completely removed in order to avoid this, an unnecessary film of the deposition-preventing plate is more likely to be peeled off (particles are more likely to be generated). In short, in the plasma CVD apparatus of FIG. 5, it was difficult to realize both the suppression of the generation of particles and the prolongation of the replacement cycle of parts.

In order to shorten or omit the dry cleaning time, it has been proposed to perform wet cleaning in which the anti-adhesion plate is removed and acid treatment is performed.
For this purpose, it is necessary to turn off the heater in the chamber, lower the temperature, return the chamber from vacuum to the atmosphere, wash the deposition prevention plate, evacuate the chamber again, and raise the temperature of the heater. However, since the apparatus stops during that time, it is not suitable for improving productivity.

The cleaning method using the auxiliary electrode in the plasma CVD apparatus shown in FIG. 6 increases the cleaning efficiency and shortens the time required for cleaning.
Although damage to the upper and lower electrodes is reduced, there is no effect of suppressing particles from unnecessary films during film formation, and the time of the cleaning step is shortened but the number of times is not reduced. In addition, an insulating part is provided in a part of the chamber to apply RF to the auxiliary electrode to form an RF introducing part, or if the auxiliary electrode is near the upper and lower electrodes during film formation, the plasma is disturbed, and the distribution of film characteristics is reduced. Since it becomes worse, the auxiliary electrode needs to have a complicated structure such as being movable so as not to hinder film formation. If the moving mechanism is omitted, it does not hinder the discharge during film formation, and
It must be a position where a sufficient effect can be exhibited during cleaning, and an appropriate mounting position has not been determined so far. For this reason, it has been very difficult to design the effective use of the auxiliary electrode, for example, the chamber becomes large due to the attachment of the auxiliary electrode, abnormal discharge occurs in the auxiliary electrode, and the cleaning effect cannot be obtained at the expected place.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and a plasma CVD apparatus which can suppress defects generated in a formed film due to particles, has less damage due to cleaning, and has high productivity. The purpose is to provide.

[0024]

According to a first aspect of the present invention, there is provided a plasma CVD apparatus comprising: a lower electrode for heating a wafer on which a film is to be formed by mounting the wafer on the upper surface thereof; and a lower electrode located above the lower electrode. A plasma CV having a high frequency power applied thereto and an upper electrode also serving as an outlet for ejecting a reaction gas.
In the device D, an auxiliary electrode for applying high frequency power, which also serves as a heater, is provided around the upper electrode.

The plasma CVD apparatus according to claim 2 is
2. The plasma CVD apparatus according to claim 1, wherein the auxiliary electrode is made of a metal plate having a built-in sheath heater.

The plasma CVD apparatus according to claim 3 is
3. The plasma CVD apparatus according to claim 1, wherein the auxiliary electrode is embedded in a groove provided in an insulator provided around the upper electrode.

[0027] The plasma CVD apparatus according to claim 4 is
A lower electrode that heats the film-forming wafer on the upper surface thereof;
Using a plasma CVD apparatus having an upper electrode that is located above the lower electrode and that also serves as an outlet for applying a high-frequency power between the lower electrode and ejecting a reaction gas, and
In the method of using a plasma CVD apparatus for forming a film, the auxiliary electrode is used as a heater during film formation, and high-frequency power is applied to the auxiliary electrode during cleaning.

[0028]

Embodiments of the present invention will be described below. FIG. 1 is a schematic diagram showing a configuration of a plasma CVD film forming apparatus of the present invention. An insulating ring 7 for preventing abnormal discharge between the upper electrode 1 and the chamber lid 5 is provided around the upper electrode 1, and a heater auxiliary electrode 6 is fitted into the insulating ring 7 by cutting a groove. Have been. The heater auxiliary electrode 6 can be heated by being energized by a heater power supply 10 via a heater SW12, and can be heated by RF-
RF can be applied from the RF power supply 11 via the SW 14.

The heater auxiliary electrode 6 heats the insulating ring 7 as a heater at the time of film formation, strengthens the unnecessary film adhered to the ring, makes it difficult to fall on the wafer 3, and suppresses generation of particles. Further, at the time of cleaning, RF-S
It functions as an auxiliary electrode for RF by applying RF through W14, and removes a strong film attached to the insulating ring 7.

Hereinafter, a film forming process and a dry cleaning process by the plasma CVD apparatus according to the present embodiment will be described.

(Film Forming Process) Here, the Si wafer 3
An example in which a nitride film (SiN film) is formed on an (8-inch wafer) will be described. First, the heater SW 12 is turned on, the heater power supply 10 is energized to the heater auxiliary electrode 6, and the insulating ring 7 is heated to 100 to 400 ° C. At this time,
Although not shown, the temperature of the heater auxiliary electrode 6 is controlled as necessary by attaching a thermocouple or the like. The wafer 3 is heated to 250 to 450 ° C. on the lower electrode 2 having a built-in heating means. The distance between the upper electrode 1 and the lower electrode 2 is 5 to 50 m
Set to m.

Subsequently, from the upper electrode 1, 10 to 500 sccm of SiH ₄ (monosilane) and NH
₃ (ammonia) 10-500 sccm, N ₂ (nitrogen) 1
0.00-7000 sccm is introduced into the chamber 4. The pressure inside the chamber 4 is set to 0.1 to 8 Torr by adjusting the exhaust conductance and the like.

In this state, the RF-SW 13 is turned on, and 13.56 MHz RF power of 100 to 1000 W is applied between the upper electrode 1 and the lower electrode 2 to generate plasma. As a result, S obtained energy by the plasma
Radicals of i (silicon), H (hydrogen), and N (nitrogen) react on the wafer 3 to form a nitride film.

At this time, also in other parts in the chamber 4, the radicals move and silicon nitride reacts, that is, an unnecessary film is formed. Here, the film attached to the insulating ring 7 is a film which is strong and hard to peel off like the film attached to the wafer 3 because radicals react well because the insulating ring 7 is heated by the heater auxiliary electrode 6. Other films attached to the side wall of the chamber 4 are brittle and insufficiently reacted because of the low temperature. However, the side wall of the chamber 4 is the wafer 3
Even if particles are further away and downstream of the gas flow, even if particles are generated, they do not easily fall on the wafer 3 and cause no problem.

When the nitride film having a desired thickness is attached to the wafer 3, the RF-SW 13 is turned off to stop the discharge, and the wafer 3 is taken out.

In the plasma CVD apparatus of the present embodiment,
Until the inside of the chamber 4 becomes heavily contaminated and the amount of particles becomes a problem, the wafer 3 is replaced and the above film formation is repeated. The number of repetitions is such that if there is no heater auxiliary electrode 6 and the chamber wall is not heated at all (the lower electrode heater is heated), particles are immediately generated and only one or two wafers can be repeatedly formed. In this embodiment, 5 to 6 sheets can be repeated, and 10 sheets can be repeated depending on the film forming conditions, and the same performance as that of the case of using the anti-adhesion plate is obtained.

(Dry Cleaning Process) When the inside of the chamber becomes sufficiently dirty and film formation cannot be continued, a dry cleaning process is executed. The process will be described below. The heater SW 12 is turned off to disconnect the heater auxiliary power supply 10 from the heater auxiliary electrode 6. This is to prevent RF leakage to the heater power supply 10 when RF power is applied to the heater auxiliary electrode 6 and to prevent temperature control from being disrupted by RF riding on the thermocouple for heater control. If it has been applied, there is no particular need to separate and heating may be performed continuously. When the heater is turned off, the temperature of the insulating ring decreases, but there is no problem during cleaning because the etching rate is sufficient even if the temperature is low. Similarly, the temperature of the lower electrode 2 may be any number of times. The distance between the upper electrode 1 and the lower electrode 2 is 5
Set to ５０50 mm. From the upper electrode 1, C ₂ F ₆ (CFC 116) 10 to 500 scc as an etching gas
m, O ₂ (oxygen) 10-500 sccm is introduced into the chamber 4. The pressure in the chamber 4 is adjusted to 0.1 to 5 Torr.

In this state, first, the RF-SW 13 is turned on, and RF power of 13.56 MHz of 100 to 1000 W is applied between the upper and lower electrodes to generate plasma. F (fluorine) radicals obtained energy by plasma
It collides with unnecessary films adhering to inner walls, etc., and decomposes and evaporates. At this time, since the discharge is between the upper and lower electrodes, unnecessary films around the upper and lower electrodes can be removed well.

When the unnecessary film has been sufficiently removed, the RF-SW
13 is turned off, RF-SW 14 is turned on and 13.56M
A RF power of 100 to 1000 W is applied to the heater auxiliary electrode 6 to generate plasma. At this time, the plasma spreads around the heater auxiliary electrode 6. Therefore, it is possible to easily clean portions such as the side wall of the chamber 4 and the insulating ring 7 from which the unnecessary film cannot be sufficiently removed by the preceding dry cleaning. When the unnecessary film in the chamber is removed and becomes clean, the RF-SW 14 is turned off to stop the discharge and finish the cleaning.

In the above process, the dry cleaning is performed in two stages, that is, the discharge of the upper electrode and the discharge of the auxiliary electrode. However, the RF-SW 13 and the RF-SW 14 are simultaneously turned on to discharge the upper electrode and the auxiliary electrode simultaneously. It is also possible to clean the space between the upper and lower electrodes and the periphery of the insulating ring 7 at a time.

FIG. 2 is a diagram showing the distribution in the chamber of the etching amount at the time of the upper electrode discharge, the auxiliary electrode discharge, and the simultaneous discharge of the upper electrode and the auxiliary electrode. As shown in this figure, in the upper electrode discharge, the etching amount is large between the upper and lower electrodes in the chamber (range of 0 to 105 mm), but the etching distribution is very small outside. Therefore, the periphery of the upper and lower electrodes can be cleaned very well, but the periphery is difficult to clean. On the other hand, in the auxiliary electrode discharge, on the contrary, the etching amount is small between the upper and lower electrodes, and the etching amount is larger outside the upper and lower electrodes. Therefore, the peripheral portion of the upper electrode can be cleaned without damaging the upper and lower electrode surfaces. When the upper electrode and the auxiliary electrode are simultaneously discharged, the etching distribution is similar to the discharge of only the upper electrode, but the amount of etching in the peripheral portion is increased due to the addition of the auxiliary electrode. Therefore, more efficient cleaning can be performed as compared with only the upper electrode.

In this embodiment, RF applied to the upper electrode
Although the power supply and the RF power applied to the auxiliary electrode are the same, the RF power applied to each electrode may be a separate RF power. In this case, the ratio of RF power applied to the upper electrode and the auxiliary electrode can be changed, and an etching distribution with higher cleaning efficiency can be obtained.

Next, the structure of the heater auxiliary electrode will be described in detail with reference to FIGS. FIG. 3 is a configuration diagram illustrating an example of the heater auxiliary electrode 6. The auxiliary electrode portion 41 has a vodka shape, and a sheath heater is embedded therein. The sheath heater is one in which an insulating material is filled in a gap so as to prevent a heating wire from contacting the sheath in a sheath (sheath) on a cylinder. As a method of embedding the sheath heater in the insulating ring, a groove may be cut into the auxiliary electrode portion 41 and the auxiliary heater may be inserted into the auxiliary electrode portion 41.
It may be made by casting. The sheath heater is embedded as much as possible to have the same length density anywhere in the auxiliary electrode portion 41 in order to uniformly heat the entire auxiliary electrode portion 41, and the two heater sheath extraction portions 44 of the auxiliary electrode portion 41 are provided.
More drawn. In FIG. 3, the sheath heater path 46 in the electrode is shown by a broken line, but this is an example, and any path is free. A copper band 45 for RF application is attached to the middle of the heater sheath extraction section 44 via a metal fitting 47 so that RF can be applied. At the end of the heater sheath take-out part 44, there is an insulating sleeve 43 for RF insulation and heater temperature insulation, and the heater wire 42 is exposed. In FIG. 3, two heater sheath take-out portions 43 are provided, and the heater wire 42 is inserted from one heater sheath take-out portion 44 and taken out from the other. However, two heater sheath take-out portions 44 are provided in one heater sheath take-out portion 44. As long as the heater wire is made to pass through, only one heater sheath extraction portion 44 is required.

FIG. 4 is a sectional view showing a state in which the heater auxiliary electrode 53 is attached to the insulating ring 52. The heater auxiliary electrode 53 is inserted into a groove provided in the insulating ring 52, thereby effectively heating the insulating ring 52. The inner surface of the chamber has an upper electrode 51 and an insulating ring 52.
And heater auxiliary electrodes 53 are arranged such that the surfaces thereof are aligned on the same plane. This is for suppressing abnormal discharge and improving plasma distribution without forming a projection in which an electric field is concentrated in the chamber. In order to apply RF to the heater sheath take-out portion 57, an insulator 58 is attached therearound so as not to come into contact with a surrounding chamber lid (not shown).

As described above, when the heater auxiliary electrode is formed, the RF introduction part and the heater current introduction part to the chamber can be made common as compared with the case where the heater and the auxiliary electrode are separately formed. Only one component is required for the vacuum sealing portion and the insulating portion, and the production cost of the chamber is the same as the conventional one, except for the production cost of the heater auxiliary electrode. In addition, considering fitting into the insulating ring, the cost is much lower than the case where a deposition plate is provided separately from the insulating ring or the auxiliary electrode is made movable. Similarly, the assembling and mounting operations are conventionally equivalent or even easier. Also, since the heater auxiliary electrode is fitted to the insulating ring, the size of the device does not increase even when the heater auxiliary electrode is attached, and it is relatively easy to modify and attach to a conventional small device.

[0046]

As described above, according to the present invention,
Since an auxiliary electrode which also serves as a heater and an electrode for RF application is provided around the upper electrode, generation of particles due to peeling of an unnecessary film due to heating of the heater during film formation can be suppressed,
In addition, by applying RF power at the time of dry cleaning, it is possible to remove unnecessary deposits and extend the life of the upper electrode. As described above, the present invention solves both the problems at the time of film formation and at the time of dry cleaning, thereby greatly improving the productivity.

Further, since the auxiliary electrode is embedded in the insulating ring so as not to form an unnecessary protruding portion in the chamber, abnormal discharge can be suppressed, and the characteristic distribution of the film thickness and refractive index of the film formed on the wafer can be suppressed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one example of a plasma CVD film forming apparatus of the present invention.

FIG. 2 is a diagram showing a distribution of an etching amount in a chamber.

FIG. 3 is a configuration diagram illustrating an example of a heater auxiliary electrode according to the present invention.

FIG. 4 is a diagram showing a state in which the heater auxiliary electrode of the present invention is attached to an insulating ring.

FIG. 5 is a configuration diagram showing an example of a conventional plasma CVD film forming apparatus.

FIG. 6 is a configuration diagram showing another example of a conventional plasma CVD apparatus.

[Explanation of symbols]

 Reference Signs List 1 upper electrode 2 lower electrode 3 wafer 4 chamber 6 heater auxiliary electrode 7 insulating ring 26 auxiliary electrode

Claims (4)

[Claims] 1. A lower electrode for heating a wafer on which a film to be formed is placed on an upper surface thereof, and also serving as an outlet for applying a high-frequency power between the lower electrode and the lower electrode and ejecting a reaction gas. Plasma CVD having upper electrode
The apparatus according to claim 1, further comprising an auxiliary electrode for applying high frequency power, which also functions as a heater, around the upper electrode.
VD device. 2. The plasma CVD apparatus according to claim 1, wherein the auxiliary electrode is formed of a metal plate having a sheath heater. 3. The plasma CVD apparatus according to claim 1, wherein the auxiliary electrode is buried in a groove provided in an insulator disposed around the upper electrode. Plasma CVD apparatus. 4. A lower electrode for heating a wafer on which a film to be formed is placed on its upper surface, and also serving as an outlet for applying a high-frequency power between the lower electrode and the lower electrode and ejecting a reaction gas. Plasma CVD having upper electrode
A method of using a plasma CVD apparatus for forming a film using an apparatus, wherein the auxiliary electrode is used as a heater during film formation, and high-frequency power is applied to the auxiliary electrode during cleaning.