JP2003201565A - Deposited film forming apparatus and deposited film forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the durability of a vacuum shaft of a rotating shaft for rotatably supporting a holder for holding a substrate in a deposited film forming apparatus, thereby improving the stability of a production system and the operation rate of the apparatus. Improve. A substrate (1) is placed in a reaction vessel (101) that can be depressurized.
The holder 106 on which the 05 is installed is connected to a rotation driving device 114 outside the reaction vessel 101, and is rotatably supported by a rotation shaft 107 extending through the bottom of the reaction vessel 101. Between the bottom surface of the holder 106 and the reaction vessel 101, around the rotation shaft 107,
A gap 108 having a width that can prevent the passage of plasma is formed. A second gas supply port 110 that supplies a vent gas that is supplied to return the inside of the reaction vessel 101 to the atmospheric pressure communicates with the gap 108 or a position closer to the rotation shaft 107 than the gap 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deposited film forming apparatus and a deposited film forming method used for manufacturing semiconductor devices, electrophotographic photoreceptors, image input line sensors, photographing devices, photovoltaic devices, and the like.

[0002]

2. Description of the Related Art Conventionally, in a manufacturing process of semiconductor devices, electrophotographic photoconductors, image input line sensors, photographing devices, photovoltaic devices, etc. Plasma CVD method,
A deposited film forming method using a reactive sputtering method, a thermal CVD method, an optical CVD method or the like is known, and many deposited film forming apparatuses using these forming methods have been put into practical use.

For example, a method of forming a deposited film using the plasma CVD method will be described. In this method, a source gas is decomposed by glow discharge to form a deposited film on a substrate. When this method is used, for example, SiH ₄ is used as the source gas.
By using hydrogenated amorphous silicon (a
It is possible to form a -Si: H) deposited film. As such a method, there is known a method of forming a deposited film while rotating a substrate in order to uniformly produce the deposited film over a wide range. With the method of rotating the substrate during the formation of the deposited film as described above, the quality and thickness uniformity of the deposited film can be improved, while the rotation mechanism provided for rotating the substrate serves as a leak source. Therefore, the vacuum holding performance of the reaction container may be deteriorated. Regarding the occurrence of leakage in the rotating mechanism part, contamination of the rotary shaft shaft and its seal part which is connected to a rotary drive device which is usually provided outside the vacuum container and extends through the wall of the vacuum container into the vacuum container. This is one factor.

As a method of preventing such contamination of the seal portion of the rotary shaft, Japanese Patent Laid-Open No. 9-213689 discloses a device provided with a screen-shaped shield plate.
The shield plates are formed concentrically with respect to the rotation axis on the lower surface of the rotation holder attached to the rotation shaft shaft for holding the substrate and on the upper surface of the base through which the rotation shaft shaft penetrates. The plates are staggered so that the combs engage one another. In addition, JP-A-11-87
In Japanese Patent Laid-Open No. 250-250, a purge gas is supplied at the time of vapor phase growth to a gap between a susceptor rotated during processing and an upper surface of a heating unit arranged below the susceptor to prevent the reaction gas from flowing around to the back surface of the wafer. A method of doing so is disclosed.

[0005]

The above method can reduce the contamination of the rotating shaft and the seal portion during the formation of the deposited film. However, contamination occurs not only during the processing of the substrate, but also after the processing, especially
Contamination may occur when a vent gas is introduced into the reaction container to return to atmospheric pressure when the substrate is taken out from the reaction container. That is, dust may be generated in the reaction container due to the generation of by-products during the formation of the deposited film or the peeling of the film adhering to the components in the reaction container after the formation of the deposited film. Such dust is rolled up by the vent gas and flows into the vicinity of the rotary shaft that is in a depressurized state at the beginning of the supply of the vent gas, which becomes a factor of contaminating the rotary shaft and the seal portion thereof. For this reason, the seal durability of the rotating shaft may be reduced.

Therefore, an object of the present invention is to provide a deposited film forming apparatus for forming a deposited film on a substrate while rotating the substrate in a reaction container under a reduced pressure. The reaction container is provided to rotate the substrate. It is an object of the present invention to provide a deposited film forming apparatus and a deposited film forming method capable of improving the seal durability of a rotary shaft that penetrates a wall of a. Further, another object of the present invention is to further improve the production system, such as improving the stability and operation rate of the production system including the deposited film forming apparatus, and reducing the cost of products produced by this production system. Is to try.

[0007]

In order to achieve the above-mentioned object, the deposited film forming apparatus of the present invention is provided with at least a depressurizable reaction vessel, and a holder provided in the reaction vessel and on which an object to be treated is installed. And a rotary shaft that rotatably supports the holder, which is connected to a rotation drive device outside the reaction container, and a gas supply port that supplies the raw material gas into the reaction container. In a deposited film forming apparatus for processing a processed material, a gap having a width capable of preventing passage of plasma is formed around the rotary shaft between the holder and the reaction container, and the gap or the gap is formed. A second gas supply port communicating with the inside of the reaction vessel at a position closer to the rotary shaft than the gap and capable of supplying a vent gas supplied to return the inside of the reaction vessel to atmospheric pressure is provided.

According to this structure, first, since there is a gap having a width that can prevent the passage of plasma around the rotary shaft, it is possible to prevent the deposited film from adhering to the rotary shaft, and the vicinity of the rotary shaft. It can suppress the generation of dust. The width of this gap is not particularly limited as long as it is a width that can prevent passage of plasma, but is at least twice the width of the sheath width of plasma or less, and it is preferably narrower.

Furthermore, by supplying the vent gas from the above-mentioned gap or a position closer to the rotary shaft shaft than the gap, from the second gas supply port communicating with the inside of the reaction vessel,
It is possible to prevent dust generated in the reaction container from flowing into the vicinity of the rotary shaft and prevent contamination of the rotary shaft by the dust.

Further, in the deposited film forming apparatus of the present invention, the shape of the holder and the reaction vessel forming the gap may be formed so that the rotary shaft is located at the blind spot when viewed from the space side where plasma is generated. preferable. That is, in this configuration, the passage that leads to the rotary shaft in the radial direction is bent, and thereby, the effect of preventing dust from entering the rotary shaft from the plasma generation space side on the radially outer side is further obtained. be able to.

The present invention is more effective in an apparatus in which the rotating shaft is located at the bottom of the reaction vessel. That is, after the deposited film is formed, dust generated due to peeling of the deposited film is likely to be deposited on the bottom of the reaction container, so that the rotary shaft is arranged at the bottom of the reaction container, and especially in an apparatus configured to penetrate the bottom surface. , The rotating shaft is easily affected by dust. Therefore, by applying the present invention to such a device, it is considered that the effect of preventing contamination of the rotary shaft can be particularly effectively obtained.

The deposited film forming method according to the present invention comprises the steps of placing an object to be treated in a reaction vessel, depressurizing the inside of the reaction vessel, forming a deposited film on the article to be treated, and Supplying vent gas and returning the internal pressure to atmospheric pressure,
In the deposited film forming method, which includes at least a step of taking out the object to be processed from the reaction container, in the step of supplying the vent gas into the reaction container using the above-described deposited film forming apparatus, the vent gas is supplied from the second gas supply port. It is characterized by supplying. By doing so, the effect of preventing dust from contaminating the rotary shaft can be obtained.

Further, the deposited film forming method according to the present invention is
Between the step of forming a deposited film and the step of supplying a vent gas into the reaction container, a purging step of supplying a purge gas into the reaction container, and / or a cooling gas is filled in the reaction container to cool an object to be processed. A cooling step may be included. In this case, in the purging step and the cooling step, it is preferable that the purging gas and / or the cooling gas be supplied through the second gas supply port. By doing so, it is possible to prevent dust from reaching the rotary shaft shaft and contaminating the rotary shaft during the supply of the purge gas and the cooling gas.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram of a parallel plate type plasma CVD deposited film forming apparatus according to a first embodiment of the present invention. This deposited film forming apparatus is provided with a reaction vessel 101 whose inside can be depressurized
have. In the reaction container 101, a holder 106 capable of stacking and holding a substrate 105 on which a film is formed is provided. The holder 106 is fixed to a rotary shaft 107 that penetrates the bottom wall of the reaction container 101 and extends into the reaction container 101, and is supported at a position where it does not come into contact with the bottom surface of the reaction container 101 so as to rotate with the rotary shaft 107. ing. Bottom of holder 106 and reaction vessel 101
A gap 108 having a width capable of blocking the passage of plasma is formed between the bottom surface and the bottom surface. The width of this gap 108 can be prevented from passing through the gap 108 by setting the width of the gap 108 to twice or less the sheath width of the plasma, for example.
The rotation drive device 11 is provided at a portion of the rotary shaft 107 that extends outside the reaction vessel 101 via a reduction gear 116.
4 is connected. At the bottom of the reaction vessel, a holder 1
A heater 115 connected to a power source (not shown) is provided below the lower surface of 06.

A cathode electrode 112 is provided in the upper part of the reaction vessel 101. In the cathode electrode 112,
A high frequency power supply 103 that supplies electric power for generating plasma is connected via a coaxial cable 117 and a matching circuit 111.

A vacuum pump 104 for evacuating the interior of the reaction vessel 101 and a gas supply system 102 for supplying a raw material gas and the like are connected to the interior of the reaction vessel 101. The vacuum pump 104 is an exhaust pipe 1 that communicates with the side of the reaction vessel 101.
It is connected to the reaction vessel 101 via 18. Two gas supply paths from the gas supply system 102 to the reaction vessel 101 are provided. One gas supply path is
It communicates with the inside of the reaction container 101 via a first gas supply port 109 which communicates with the inside of the reaction container 101 at a side portion. The other gas supply path communicates with the inside of the reaction vessel 101 at a portion where a gap 108 is formed between the bottom of the reaction vessel 101 and the bottom surface of the holder 106, or at a position closer to the rotary shaft 107 than that. Second gas supply port 1
It communicates with the inside of the reaction container 101 via 10. Each gas supply path is provided with a valve.

As the source gas supplied from the gas supply system 102, for example, SiH ₄ , GeH ₄ , H ₂ , B ₂ H
₆ , PH ₃ , CH ₄ , NO, Ar, He, N _{2 and the} like are used. The gas supply system 102 can supply such a raw material gas, a vent gas described later, and the like at a predetermined flow rate by adjusting with a mass flow controller or the like.
A conductance valve 113 that adjusts the exhaust speed is provided in the exhaust path formed by the exhaust pipe 118. With these configurations, in the deposited film forming apparatus according to the present embodiment, the conductance valve 11 is supplied while the gas is being supplied from the gas supply system 102 at a predetermined flow rate.
By adjusting 3, the pressure inside the reaction vessel 101 can be adjusted to a predetermined pressure.

Next, FIG. 2 is a schematic view of a plasma CVD deposited film forming apparatus according to a second embodiment of the present invention. The deposited film forming apparatus shown in FIG. 1 is an apparatus mainly for processing a flat substrate (substrate 105), whereas it is an apparatus for processing a cylindrical substrate 205.

This deposited film forming apparatus has a cylindrical reaction vessel 201 whose inside can be depressurized. Reaction vessel 201
Inside, a plurality of cylindrical holders 206 capable of holding the cylindrical substrate 205 forming the film are provided. A heater 215 connected to a power source (not shown) is provided in the center of the holder 206. Each holder 206 is fixed to a rotating shaft 207 that penetrates the wall of the bottom of the reaction container 201 and extends into the reaction container 201.
Each rotary shaft 207 has a rotary shaft bearing 32.
It is rotatably supported by 2 (see FIGS. 3 and 4). Then, each holder 206 is attached to each rotary shaft 20
It is supported at a position where it does not come into contact with the bottom surface of the reaction container 201 so that it can rotate together with 7. Between the bottom surface of each holder 206 and the bottom surface of the reaction vessel 201, a gap 208 having a width that can prevent passage of plasma is formed. By setting the width of the gap 208 to be equal to or less than twice the width of the plasma sheath, it is possible to prevent the plasma from passing through the gap 208. Each rotary shaft 207 is connected to a rotary drive device 214 via a reduction gear 216 at a portion extending outside the reaction vessel 101.

The rotating shaft 207 is the reaction vessel 201.
As shown in FIG. 3, a rotary shaft shaft vacuum seal portion 321 is provided in the portion that enters the inside. It is preferable to use an O-ring, a magnetic fluid, an omni seal (trade name of Huron Co., Ltd.) or the like for the vacuum seal portion. Although FIG. 3 shows the configuration of the second embodiment, the vacuum seal portion is similarly provided in the first embodiment.

As shown in FIG. 4, the gap between the reaction vessel 201 and the bottom surface of the holder 206 is formed so that the rotary shaft 207 is located at a blind spot as seen from the space side where plasma is generated. May be. In other words, in this configuration, the passage extending in the radial direction from the outer side in the radial direction through the gap communicating with the rotary shaft 207 is a non-linear, that is, a bent passage. In the example shown in FIG. 4, an annular protrusion that extends upward and is concentric with the rotary shaft 207 is formed in the bottom portion of the reaction vessel 201, and an annular groove is formed in the bottom surface of the holder 206. And the upper part of this annular protrusion has entered into the annular groove. Due to the projection and the groove combined in this way, the path toward the rotary shaft shaft 207 in the radial direction is bent. Such a configuration may be provided in the deposited film forming apparatus of the first embodiment.

A vacuum pump 204 for evacuating the interior of the reaction vessel 201 and a gas supply system 202 for supplying a raw material gas and the like are connected to the interior of the reaction vessel 201. The vacuum pump 204 is connected to the reaction container 201 via an exhaust pipe 218 that communicates with the center of the bottom of the reaction container 201.
Two gas supply paths from the gas supply system 202 to the reaction vessel 201 are provided. One of the gas supply paths is a first gas supply port which is formed by a pipe having a plurality of holes opened in a portion extending into the reaction vessel 201 by entering the reaction vessel 201 from the bottom and extending straight upward. It communicates with the inside of the reaction container 201 via 209. The other gas supply path is provided at a portion of the bottom of the reaction vessel 201 where a gap 208 is formed between the bottom of each holder 206 or the rotary shaft 20.
It communicates with the inside of the reaction container 201 through the second gas supply port 210 which communicates with the inside of the reaction container 201 at the position on the 7 side. Each gas supply path is provided with a valve.

As the source gas supplied from the gas supply system 202, for example, SiH ₄ , GeH ₄ , H ₂ , B ₂ H
₆ , PH ₃ , CH ₄ , NO, Ar, He, N _{2 and the} like are used. The gas supply system 202 can supply such a raw material gas and a vent gas described later by a mass flow controller or the like at a predetermined flow rate.
A conductance valve 213 for adjusting the exhaust speed is provided in the exhaust path constituted by the exhaust pipe 218. With these configurations, in the deposited film forming apparatus of the present embodiment, the conductance valve 21 is supplied while the gas is being supplied from the gas supply system 202 at a predetermined flow rate.
By adjusting 3, the pressure inside the reaction vessel 201 can be adjusted to a predetermined pressure.

A plurality of cathode electrodes 212 extending in the vertical direction along the side wall are provided outside the side wall of the reaction vessel 201. A high-frequency power source 203 that supplies electric power for generating plasma is connected to each cathode electrode 212 via a common coaxial cable 217 and a matching circuit 211. The electric power supplied from the coaxial cable 217 is supplied to the power branch plate 22 arranged above the reaction vessel 201.
It is distributed to each cathode electrode 212 via 0. Around the power branch plate 220 and each cathode electrode 212, a shield container 219 is formed to prevent the electromagnetic waves generated from them from being emitted to the outside.

Next, regarding a method of forming a deposited film using these deposited film forming apparatuses, an a-Si: H deposited film is formed on the substrate 105 using the deposited film forming apparatus of the first embodiment. A case will be described as an example.

First, the substrate 105 is placed on the holder 106 in the reaction vessel 101, and the inside of the reaction vessel 101 is evacuated by the vacuum pump 104 to a desired pressure. Next, from the gas supply system 102 to the first gas supply port 10
An inert gas, for example, Ar gas is introduced into the reaction vessel 101 at a predetermined flow rate through 9. Then, the opening of the conductance valve 113 is adjusted so that the inside of the reaction vessel 101 is maintained at a predetermined pressure, and the substrate 115 is moved to 2 by the heater 115.
Heat and control at 00-300 ° C.

When the substrate 105 can be heated and controlled to a desired temperature, the supply of Ar gas is stopped, the Ar gas in the reaction vessel 101 is exhausted sufficiently by the vacuum pump 104, and the gas is supplied from the gas supply system 102 into the reaction vessel 101. SiH ₄ gas is supplied as a source gas at a predetermined flow rate through the first gas supply port 109. And conductance valve 11
The pressure inside the reaction vessel 101 is set to a desired pressure by adjusting the opening degree of No. 3.

Next, from the high frequency power source 103 to the matching circuit 11
High-frequency power is applied to the cathode electrode 112 via 1 to generate plasma of the raw material gas, and a-S on the substrate 105 is generated.
The formation of the i: H deposited film is started. When the film thickness of the a-Si: H deposited film reaches a desired film thickness, the high frequency power supply is stopped, the SiH ₄ gas supply is stopped, and the formation of the a-Si: H deposited film is completed.

After the formation of the a-Si: H deposited film, the vacuum pump 104 evacuates while introducing the purge gas from the gas supply system 102 to purge the inside of the reaction vessel 101 a plurality of times. After that, an inert gas, for example, He gas, is filled as a cooling gas from the gas supply system 102 into the reaction vessel 101 at a predetermined pressure for cooling. When the temperature of the substrate 105 is sufficiently cooled, the cooling gas is exhausted using the vacuum pump 104, and then the vent gas is introduced through the second gas supply port 110 to return the inside of the reaction vessel 101 to the atmospheric pressure. Finally, the substrate 105 is taken out from the reaction container 101.

In the deposited film forming apparatus according to the first and second embodiments described above, the rotary shaft 1 is provided between the bottom surfaces of the holders 106 and 206 and the bottom surfaces of the reaction vessels 101 and 201.
Gaps 108 and 208 having a width capable of blocking the passage of plasma are formed around 07 and 207. That is, gaps 108 and 208 having a width that plasma cannot pass through are provided in the paths from the region where plasma is generated in the reaction vessels 101 and 201 to the rotary shafts 101 and 201. Thereby, according to each embodiment of the present invention,
Plasma can be prevented from entering the rotating shafts 107 and 207 and forming a deposited film there.

Further, in the deposited film forming apparatus of each embodiment, the reaction vessel 10 is connected to the gas supply systems 102 and 202.
There are two systems of gas supply paths leading to the inside of 1,201. One is the substrate 105 and the cylindrical substrate 20 is the other.
5 is a path passing through the first gas supply ports 109 and 209 configured so that the source gas can be efficiently supplied to the vicinity of No. 5. The other is a portion where the above-mentioned gaps 108 and 208 are formed, or the rotating shaft 107,
It is a path that passes through the second gas supply ports 110 and 210 that communicate with the inside of the reaction vessels 101 and 201 at the position on the side of 207. Then, when introducing the vent gas into the reaction vessels 101, 201, the second gas supply ports 110, 2
Gas is introduced via 10. By doing so, the reaction vessel 101,
Even if dust is generated in 201, the dust is caused to flow by the introduced vent gas and the rotating shaft 10
It is possible to prevent reaching 7,207. Further, as shown in FIG. 4, the rotation shaft shafts 107 and 207 are arranged so as to be in a dead zone when viewed from the side of the space in which the plasma is generated on the outer side in the radial direction.
Dust generated in the inside of the rotary shaft shaft 10
It is possible to further obtain the effect of preventing the arrival at 7,207. The dust generated in the reaction vessels 101 and 201 includes by-products generated in the deposited film forming step, such as polysilane in the case of forming an a-Si: H deposited film. Further, the deposited film attached to the components in the reaction vessels 101 and 201 is peeled off due to a change in stress due to a temperature change during the purge process, the cooling process, and the vent process after the deposited film forming process, and becomes dust. Can also be considered.

As described above, according to the respective embodiments of the present invention, it is possible to effectively prevent the rotary shafts 107 and 207 from being contaminated by the deposited film or dust.
As a result, the seal durability of the rotary shafts 107 and 207 can be improved, and the stability of the production system and the device mobility can be improved.

In FIGS. 1 and 2, the holders 106 and 2 are
Although it is shown that the bottom surface of 06 and the reaction vessels 101 and 201 have a constant interval as a whole, the present invention is not limited to such a configuration. The gaps 108, 20 having a width capable of blocking the passage of plasma as described above
8 may be partially formed at least around the rotary shafts 107 and 207. Further, in each embodiment, the purge gas and the cooling gas are also supplied to the reaction vessels 101 and 210 through the second gas supply ports 110 and 210.
01 may be introduced. This is preferable because it is considered that dust can be moved away from the rotary shafts 107 and 207.

[0035]

The present invention will be described below with reference to more specific examples. The present invention is not limited to these.

Example 1 In this example, a deposited film was formed using a parallel plate type plasma CVD deposited film forming apparatus as shown in FIG. As described in the embodiment of the invention, the treatment was performed in the order of the charging step, the heating step, the film forming step, the purging step, the cooling step, and the venting step. The processing in these steps will be described more specifically.

First, in the loading step, the substrate 105 was loaded on the holder 106 in the reaction vessel 101. Then, the inside of the reaction vessel 101 was evacuated to 50 Pa or less by the vacuum pump 104.

In the heating step, the holder 106 and the substrate 105 loaded on the holder 106 were rotated at 1 rpm by the rotation driving device 114 via the rotary shaft 107. Then, Ar gas from the gas supply system 102 is passed through the first gas supply port 109 to 500 ml / m 2.
The pressure in the reaction vessel 101 was set to 65 Pa by adjusting the opening of the conductance valve 113. Then, when the flow rate of Ar gas and the internal pressure of the reaction vessel 101 become stable, the heater 11
The substrate was heated to 250 ° C. for 90 min. The temperature control of the substrate 105 was continued until the deposition film formation was completed.

In the film forming step, the supply of Ar gas was stopped, the inside of the reaction vessel 101 was evacuated to 1 Pa or less, and then, as shown in Table 1.
An a-Si: H deposited film was deposited to a thickness of 10 μm under the film forming conditions of.

[0040]

[Table 1]

In the purging step, the inside of the reaction vessel 101 is
After first vacuuming to a or less, first gas supply port
Ar gas is supplied through 109 to perform purging a plurality of times.
It was In the cooling process, through the first gas supply port 109
He gas as a cooling gas in the reaction vessel 101 is 1 × 1
0³It was filled with Pa and the substrate 105 was naturally cooled. Venting
However, once the He gas is exhausted, the second gas supply port
Through N 110 ₂Supply gas to the reaction vessel 101
Was returned to atmospheric pressure, and the substrate 105 was taken out.

In order to evaluate this example, the above series of steps was set as one cycle, and 10 cycles were repeated. The evaluation results will be described later in comparison with Comparative Example 1 shown below.

(Comparative Example 1) In this comparative example, an apparatus as shown in FIG. 1 was used, and 10 cycles of processing were performed under the same apparatus configuration and processing step conditions as in Example 1. However, in this comparative example, the vent gas is supplied to the first gas supply port 1 in the vent process.
Example 1 is that the reaction solution was supplied into the reaction vessel 101 through 09.
Different from

(Evaluation of Example 1) With respect to Example 1, the rotary shaft shaft 107 was evaluated for dust contamination prevention and vacuum airtight durability by the following methods and standards.

(Evaluation Method of Dust Contamination Prevention) Dust contamination of the vacuum seal portion of the rotary shaft 107 was visually evaluated. Dust contamination of the vacuum seal portion of the rotary shaft 107 is based on Comparative Example 1 when the amount of dust increases ×,
When the amount of dust was about the same, it was evaluated as Δ, when the amount of dust decreased, it was evaluated as ◯, and when almost no dust was confirmed, it was evaluated as ◎.

(Evaluation method of vacuum tightness durability) He leak detector (PORTATEST manufactured by Varian)
2) was used to measure the vacuum tightness of the seal portion of the rotary shaft 107. The vacuum airtightness at the seal portion of the rotary shaft 107 is based on before the start of cycle processing, when there is no change, it is indicated as ◯, when it is deteriorated but there is no problem, it is indicated as Δ, and when it is clearly deteriorated, it is indicated as ×. evaluated.

Table 2 shows the results of the above evaluations.

[0048]

[Table 2]

As a result of the evaluation, in Example 1, it was confirmed that both the "dust contamination preventing ability" and the "vacuum airtight durability" were improved as compared with Comparative Example 1, and the excellent effect of the present invention was confirmed. .

(Example 2) In this example, a deposited film was formed by using the apparatus shown in FIG. At this time, as shown in FIG. 3, a device was used in which a gap 208 formed between the holder 206 and the bottom of the reaction vessel 201 was connected to the rotary shaft shaft almost straightly. The cycle treatment was performed in the order of a charging step, a heating step, a film forming step, a purging step, a cooling step, and a venting step.

First, in the charging step, a degreased and washed diameter of 80
A cylindrical substrate 205 made of aluminum and having a length of 358 mm was mounted on a holder 206. Then, the inside of the reaction vessel 101 was evacuated to 50 Pa or less by the vacuum pump 204.

In the heating step, the holder 206 and the cylindrical substrate 205 loaded on the holder 206 are rotated by 1 rpm by the rotary drive device 214 via the rotary shaft 207.
I rotated it. Then, from the gas supply system 202 to A
500 m of r gas through the first gas supply port 209
The pressure in the reaction vessel 201 was set to 65 Pa by adjusting the opening degree of the conductance valve 213. Then, when the flow rate of Ar gas and the internal pressure of the reaction vessel 201 become stable, the cylindrical substrate 205 is moved by the heater 215 for 90 min. In 2
It was heated to 30 ° C. and controlled. The temperature control of the cylindrical substrate 205 was continued until the deposition film formation was completed.

In the film forming step, the supply of Ar gas was stopped, and the inside of the reaction vessel 201 was evacuated to 1 Pa or less.
Under the film forming conditions of, the charge injection blocking layer, the photosensitive layer (photoconductive layer 1,
2), a deposited film was formed in this order on the surface layer to produce an a-Si: H-based photoreceptor. At this time, the raw material gas was introduced through the first gas supply port 209.

[0054]

[Table 3]

In the purging process, the inside of the reaction vessel 201 is
After evacuation to a or less, Ar gas was supplied through the first gas supply port 209 to perform purging a plurality of times. In the cooling step, He gas as a cooling gas was supplied into the reaction container 201 through the first gas supply port 209 to set the internal pressure of the reaction container 201 to 1 × 10 ³ Pa and naturally cool the cylindrical substrate 205. In the vent process, H for cooling
After the e gas is once exhausted, the second gas supply port 210
N ₂ gas was supplied to return the inside of the reaction vessel 201 to atmospheric pressure, and the cylindrical substrate 205 was taken out from the reaction vessel 201.

In order to evaluate this example, the above series of steps was set as one cycle, and 10 cycles were repeated. The evaluation results will be described later together with Examples 3 to 5 in comparison with Comparative Example 2 shown below.

(Embodiment 3) In this embodiment, an apparatus as shown in FIG. 2 was used, and 10 cycles of repetitive processing were carried out using the same apparatus configuration and processing process conditions as in Embodiment 2. However, in this embodiment, as shown in FIG. 4, the gap 208 formed between the holder 206 and the bottom of the reaction vessel 201 has a configuration in which the rotary shaft 207 is located in a blind spot when viewed from the discharge space side. The present embodiment is different from the second embodiment in that the existing device is used.

(Comparative Example 2) In this comparative example, an apparatus as shown in FIG. 2 was used, and 10 cycles of processing were performed using the same apparatus configuration and processing step conditions as in Example 2. However, this comparative example is different from Example 2 in that the vent gas was supplied through the first gas supply port 209 in the vent process.

(Embodiment 4) In this embodiment, an apparatus as shown in FIG. 2 was used, and 10 cycles of treatment were carried out using the same apparatus configuration and treatment process conditions as in Embodiment 3. However, the present embodiment is different from the third embodiment in that the cooling gas is supplied through the second gas supply port 210 in the cooling process.

(Embodiment 5) In this embodiment, an apparatus as shown in FIG. 2 was used, and 10 cycles of treatment were carried out using the same apparatus configuration and treatment process conditions as in Embodiment 4. However, this embodiment is different from the fourth embodiment in that the purge gas is supplied through the second gas supply port 210 in the purging process.

(Evaluation of Examples 2 to 5) Based on Comparative Example 2, the rotary shaft 207 was evaluated for dust contamination prevention property in the same manner as in Example 1. Regarding the vacuum-tightness durability of each Example, the vacuum-tightness durability before the cycle treatment of each Example was used as a standard, and the same criteria as in Example 1 were used.
It was evaluated by the method. The evaluation results are shown in Table 4.

[0062]

[Table 4]

As a result of the evaluation, in all of Examples 2 to 5, both the "dust contamination preventing ability" and the "vacuum airtight durability" were improved, and the excellent effect of the present invention was confirmed.

[0064]

EFFECTS OF THE INVENTION According to the present invention, at least in a reaction vessel capable of depressurizing, while the object to be processed held by the holder is rotated together with the holder, the film to be processed is processed by using the plasma of the raw material gas. In the apparatus, a gap between the reaction container and the holder is formed around the rotary shaft that supports the holder and has a width that can prevent passage of plasma. Further, a gas supply port communicating with the inside of the reaction vessel is provided at a position of a gap having a width that can prevent the passage of this plasma, or at a position closer to the rotating shaft than the gap, and from this gas supply port, the inside of the reaction vessel is brought to atmospheric pressure. Vent gas to be fed into the reaction vessel for feeding back is fed. As a result, it is possible to prevent the film from being deposited on the rotating shaft during the formation of the deposited film, and to prevent dust generated due to film peeling in the reaction vessel from adhering to the rotating shaft after the deposition film is formed. It can be prevented. That is, according to the present invention, it is possible to prevent contamination of the rotary shaft and improve the vacuum seal durability of the rotary shaft. As a result, it is possible to improve the stability of the production system and the operation rate of the apparatus, and it is possible to improve the product quality and reduce the production cost.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of a parallel plate type plasma CVD deposited film forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic sectional view of a plasma CVD deposited film forming apparatus for forming a deposited film on a cylindrical substrate according to a second embodiment of the present invention.

3 is an enlarged view of the vicinity of a rotary shaft in the apparatus of FIG. 2, showing an example of the configuration of the apparatus used in Example 2. FIG.

FIG. 4 is an enlarged view of the vicinity of a rotary shaft in the apparatus of FIG. 2, showing a configuration example of the apparatus used in Examples 3 to 5.

[Explanation of symbols]

101,201 Reaction vessel 102,202 gas supply system 103,203 high frequency power supply 104,204 Vacuum pump 105 substrate 106,206 holder 107,207 rotary shaft 108, 208 gap 109,209 First gas supply port 110, 210 Second gas supply port 111,211 Matching circuit 112,212 cathode electrode 113,213 Conductance valve 114,214 rotary drive device 115,215 heater 116,216 reduction gears 117,217 coaxial cable 118,218 Exhaust pipe 205 cylindrical substrate 219 shielded container 220 power distribution board 321 Rotary shaft shaft seal 322 rotating shaft bearing

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G03G 5/08 336 G03G 5/08 336 H01L 21/205 H01L 21/205 (72) Inventor Kunimasa Kawamura Tokyo 3-30-2 Shimomaruko, Ota-ku Canon Inc. F-term (reference) 2H068 DA05 DA28 DA56 DA57 DA58 EA24 4K030 DA06 EA11 KA26 LA16 LA17 5F045 AA08 BB15 EB12

Claims (6)

[Claims] 1. A reaction vessel capable of at least decompressing, a holder provided in the reaction vessel, on which an object to be treated is installed, and the holder, which is connected to a rotation driving device outside the reaction vessel, is rotatable. In the deposited film forming apparatus, which is provided with a rotary shaft that supports a raw material gas, and a gas supply port that supplies a raw material gas into the reaction vessel, and that generates plasma of the raw material gas to process the object to be processed, the holder and A gap having a width capable of preventing passage of the plasma is formed around the rotary shaft between the reaction container and the gap or at a position closer to the rotary shaft than the gap. An apparatus for forming a deposited film, comprising: a second gas supply port communicating with the inside of the reaction container and capable of supplying a vent gas supplied to return the inside of the reaction container to atmospheric pressure. 2. The shape of the reaction vessel and the holder forming the gap is formed so that the rotary shaft is located at a blind spot when viewed from the space side where the plasma is generated. The deposited film forming apparatus as described in 1. 3. The deposited film forming apparatus according to claim 1, wherein the rotary shaft is arranged at the bottom of the reaction vessel. 4. A step of installing an object to be treated in a reaction vessel, a step of decompressing the inside of the reaction vessel, a step of forming a deposited film on the treated article, and supplying a vent gas into the reaction vessel. And a step of returning the internal pressure to atmospheric pressure, and a step of taking out the object to be treated out of the reaction container, wherein the deposited film forming apparatus according to claim 1 is used. A method for forming a deposited film, characterized in that, in the step of supplying the vent gas into the reaction container, the vent gas is supplied from the second gas supply port. 5. A purge step of supplying a purge gas into the reaction vessel is included between the step of forming the deposited film and the step of supplying the vent gas into the reaction vessel,
The deposited film forming method according to claim 4, wherein in the purging step, the purge gas is supplied from the second gas supply port. 6. A cooling step for cooling the object to be processed by filling a cooling gas in the reaction vessel between a step of forming the deposited film and a step of supplying the vent gas into the reaction vessel. The method for forming a deposited film according to claim 4, further comprising supplying the cooling gas from the second gas supply port in the cooling step.