JP2002004052A - Method for cleaning film forming apparatus and method for forming deposited film - Google Patents

Abstract

An object of the present invention is to provide an electrophotographic photosensitive member for removing an adsorbent which causes a defect such as particles and abnormal growth from the inside of a reaction vessel after opening to the atmosphere to obtain an electrophotographic photosensitive member having few defects. An object of the present invention is to provide a method for effectively cleaning a body film forming apparatus and a film forming method using the same. A method of cleaning a film forming apparatus for forming a deposited film on a substrate in a reaction vessel under a pressure lower than the atmospheric pressure, the method comprising: (1) removing a deposited film adhered to an inner wall of the reaction vessel; And (2) a step of opening the reaction vessel to the atmosphere; and (3) a step of cleaning the inner wall of the reaction vessel with a cleaning gas containing at least ClF ₃ or a plasma of the cleaning gas,
The present invention provides a method for cleaning a deposition film forming apparatus, wherein the step (3) is performed last among the three steps.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deposition method for producing a deposition film particularly suitable as a semiconductor element such as a light receiving member for electrophotography, a solar cell, a line sensor for image input, an imaging device, and a TFT on a substrate. The present invention relates to a method of forming a film and a method of cleaning a deposited film forming apparatus.

[0002]

2. Description of the Related Art Conventionally, light receiving members for electrophotography, solar cells, line sensors for image input, image pickup devices, TFTs
As a deposited film used as a semiconductor element such as, for example, amorphous silicon, for example, amorphous silicon compensated with hydrogen and / or halogen (for example, fluorine, chlorine, etc.) (hereinafter referred to as “a-Si (H, X)”) ) Films and the like have been proposed, some of which have already been put to practical use. Various apparatuses for forming a deposited film such as an a-Si (H, X) film have been proposed, and examples thereof include a vacuum evaporation method, an ion plating method, a sputtering method, a thermal CVD method, a plasma CVD method, A photo-CVD method and the like, and among them, a film forming method utilizing a gas phase chemical reaction under reduced pressure such as a plasma CVD method are often used.

When a deposited film is formed on a substrate by these film forming methods, the deposited film or a powdery polymer (hereinafter abbreviated as polysilane) is deposited on a member or the like used in a film forming chamber. . For example, when a film is formed by a plasma CVD method based on glow discharge decomposition, a susceptor, a counter electrode, or an inner wall in the reaction vessel, which is a portion other than the substrate in the deposition film forming apparatus (hereinafter abbreviated as “reaction vessel”). A deposited film or polysilane is formed. The deposited film or polysilane remaining in the reaction vessel becomes impurities or particles in the target film, and greatly reduces the yield of the target film. When the deposition of the target film inside the reaction vessel or polysilane is repeated while leaving it unattended, the yield of the target film is greatly reduced due to particles and abnormal growth caused by the deposited film peeling from the inside of the reaction vessel. I do.

[0004] For this reason, the inside of the reaction vessel is cleaned after several film forming cycles or every film forming cycle to remove the film or polysilane deposited inside. The removal is performed by manually cleaning the inside of the reaction vessel opened to the atmosphere using a solvent and / or gasifying the elements forming the deposited film or polysilane by a gas phase chemical reaction using plasma. .

More specifically, a cleaning method using plasma is described.
Uh, CF_FourGas, NF_ThreeGas, SF ₆Reaction gas
Flow into the chamber and excite with energy such as plasma, heat, light, etc.
In the starting state, a deposited film or polysilane is formed
Reacts with elements, turns those elements into gas molecules,
Exhaust out of the device by steps.

[0006] These conventionally used gases do not themselves have an etching action, but can be used to vaporize deposited films and the like by setting them in an excited state. On the other hand, ClF ₃ gas itself has an etching effect, and is starting to attract attention as various cleaning gases.

[0007] ClF ₃ gas is decomposed with low energy and is highly reactive, and has an extremely high etching rate as compared with a conventional etching gas. Various cleaning methods using ClF ₃ utilizing this property have been proposed. For example, Japanese Patent Application Laid-Open No. Sho 64-17857 discloses ClF,
An attempt to clean a metal film deposited on the inner wall of a reaction vessel of a film forming apparatus using a cleaning gas containing at least one of ClF ₃ and ClF ₅ is described.

[0008] The method disclosed in JP-A-64-17857 is
It is very effective in removing a metal film or the like deposited on the inner wall of the reaction vessel.

However, if the cleaning by the conventional method is repeated many times, polysilane or the like is gradually deposited on a portion of the reaction vessel where the plasma or the cleaning gas is difficult to reach. These deposited films were peeled off from the inner wall of the reaction vessel and created defects in the deposited films.

[0010] In order to suppress the occurrence of such defects, after the plasma cleaning is performed several times, the reaction vessel must be opened to the atmosphere, and the solvent must be manually cleaned using a solvent to remove the deposited film. Was.

However, when the present inventors open the atmosphere to the atmosphere and perform hand washing of the reaction vessel, the moisture, oxygen,
It has been found that organic substances and the solvent used for cleaning are adsorbed on the inner wall of the reaction vessel, and these components cause minute defects on the surface of the photoreceptor.

Until now, the main purpose of the electrophotographic apparatus is to copy characters, and since the main purpose is to copy originals (so-called line copies) of only characters, water, oxygen, organic substances and solvents adsorbed on the inner wall of the film forming apparatus. The minute image defects generated due to the above factors did not pose a serious problem in practical use.

However, a recent electrophotographic apparatus is required to image a manuscript including a halftone such as a photograph, and an electrophotographic photoreceptor is required to have a much higher resolution than before. As a result, minute defects on the electrophotographic photosensitive member that could not be recognized conventionally can be visualized, and minute image defects generated by water, oxygen, organic substances, solvents, and the like adsorbed on the inner wall of the film forming apparatus can be further reduced. It has begun to be noticed as a major factor in preventing the high performance of photographic devices.

[0014]

DISCLOSURE OF THE INVENTION The present invention is directed to an electrophotographic photosensitive member for removing an adsorbent which causes defects such as particles and abnormal growth from the inside of a reaction vessel after opening to the atmosphere to obtain an electrophotographic photosensitive member having few defects. An object of the present invention is to provide a method for effectively cleaning a body film forming apparatus.
Another object is to provide a method for forming a deposited film using the cleaning method.

[0015]

SUMMARY OF THE INVENTION The present invention is a method of cleaning a film forming apparatus for forming a deposited film on a substrate in a reaction vessel under a pressure lower than atmospheric pressure. Removing the deposited film attached to the inner wall; (2) releasing the reaction vessel to the atmosphere; and (3) at least ClF
Cleaning the inner wall of the reaction vessel with a cleaning gas containing ₃ or a plasma of the cleaning gas, wherein at least the step (3) is performed.
Is performed last, and a method for cleaning a deposition apparatus for depositing a deposited film is provided.

Further, according to the present invention, there is provided a cleaning apparatus for forming a film on a substrate by a chemical vapor deposition method as a device for forming a film on a substrate under a pressure lower than the atmospheric pressure. Provide a way.

Further, the present invention provides a method of cleaning a film forming apparatus using an apparatus for forming a film on a substrate by sputtering as an apparatus for forming a film on a substrate under a pressure lower than the atmospheric pressure. .

The present invention also provides a method for cleaning the film forming apparatus, wherein the cleaning gas is introduced into the reaction vessel in a stationary or flowing manner in the step (3).

The present invention also provides the cleaning method of the film forming apparatus, wherein in the step (1), the deposited film adhered to the inner wall of the reaction vessel is removed by plasma.

Further, the present invention provides a method for forming a deposited film, wherein the deposited film is formed on a substrate after the reaction container is cleaned by the method for cleaning a reaction container of the film forming apparatus.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is based on the following findings obtained from the present inventor's experience in manufacturing a photoreceptor of an electrophotographic apparatus.

When the reaction vessel is opened to the atmosphere and hand-washing with a solvent is performed, the surface of the electrophotographic photoreceptor formed immediately thereafter is innumerably minute in size due to adsorbed substances on the inner wall of the reaction vessel. Defects (abnormal growth, particles) occur. In order to suppress the occurrence of this defect, the present inventors made an attempt to perform cleaning while heating the reaction vessel and an attempt to perform a heat treatment using an inert gas. It could not be reduced.

Accordingly, the present inventors have intensively studied an efficient and more stable cleaning method and have arrived at the present invention.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a schematic view showing an example of the configuration of an apparatus for producing a deposited film for an electrophotographic photosensitive member according to the present invention. In this example,
Plasma CVD for forming an amorphous silicon film on the surface of a cylindrical substrate to form an electrophotographic photoreceptor
Although a film forming apparatus is illustrated, the cleaning method of the present invention is applicable to not only this film forming apparatus but also any apparatus that forms a film under a pressure lower than the atmospheric pressure. For example, a sputtering film forming apparatus, an optical CVD film forming apparatus, a vacuum evaporation apparatus, and the like.

The shape of the substrate is not limited to a cylindrical shape, but may be, for example, a flat shape or another shape.

In FIG. 1, a reaction vessel (101) has a cylindrical substrate (102), a substrate holder (108) for supporting the cylindrical substrate, and a substrate heating heater (1).
03), a source gas introduction pipe (104), a base plate (106), and a gate valve (107). Also, the reaction vessel (10) is supplied from a high frequency power supply (105) via a matching box (not shown) from a power supply (not shown).
1). The means for introducing the source gas for the deposited film and for cleaning is a mass flow controller (10
9), source gas inflow valve (110), exhaust valve (1)
11). <Formation of Deposited Film> Formation of a deposited film using this apparatus can be performed, for example, as follows. First, the reaction vessel (1
01), the inside of the reaction vessel (101) is exhausted by an exhaust device (not shown) via an exhaust valve (111). Subsequently, the temperature of the cylindrical substrate (102) was set to 20 ° C. by the substrate heating heater (103).
The temperature is controlled to a predetermined temperature of 400 to 400 ° C. Cylindrical substrate (1
When the temperature of 02) reaches a predetermined temperature, the raw material gas whose flow rate has been controlled by the mass flow controller (109) is supplied from the raw gas introduction pipe (104) to the reaction vessel (101) via the raw gas inflow valve (110). ). At that time, the internal pressure of the reaction vessel (101) was 133 Pa
An exhaust device (not shown) is adjusted to have the following predetermined pressure. When the internal pressure becomes stable, the high-frequency power supply (10
Electric power is introduced into the reaction vessel (101) from 5) through a matching box (not shown) to generate glow discharge. The raw material gas introduced into the reaction vessel (101) is decomposed by the discharge energy, and the cylindrical substrate (10) is decomposed.
2) A deposited film of a predetermined material is formed thereon. In order to achieve uniform film formation, the cylindrical substrate (102) is rotated at a predetermined speed by a driving device (not shown) during the film formation.

Since the cleaning method of the present invention is carried out after the deposition film is removed from the inside of the film forming apparatus and the reaction vessel is opened to the atmosphere, it does not depend on the type of film formed on the substrate. As long as the fluorinated compound or the chlorinated compound of the element constituting the deposited film is volatile, it can be carried out after forming any material. Si, Ti, V, Mo, S
Metal films such as b, W, Se, Ir, and Ge, alloy films of these metals, and oxide films and nitride films of these metals may be formed.

The cleaning method of the present invention is as follows.
Although the type of film formed on the substrate is not limited, it is particularly preferable to use the film for cleaning an amorphous silicon film forming apparatus.

For forming this amorphous silicon film,
Silane (SiH)_Four), Disilane
(Si_TwoH₆), Silicon tetrafluoride (SiF_Four), Disilicon hexafluoride
(Si _TwoF₆) And other amorphous silicon forming gas
Is also effective using a mixed gas thereof. With dilution gas
Hydrogen (H_Two), Argon (Ar), helium (H
It is also effective to use e). Also, the band gap of the deposited film
Nitrogen (N
_Two), Ammonia (NH_Three) And other elements containing nitrogen atoms, acids
Element (O_Two), Nitric oxide (NO), nitrogen dioxide (N
O_Two), Nitrous oxide (N _TwoO), carbon monoxide (CO),
Carbon oxide (CO_Two), Such as elements containing oxygen atoms, methane
(CH_Four), Ethane (C_TwoH₆), Ethylene (C_TwoH_Four),
Acetylene (C_TwoH_Two), Propane (C_ThreeH₈) Etc.
Element, germanium tetrafluoride (GeF_Four), Nitrogen fluoride (N
F_Three) Etc. or a mixed gas of these compounds
Is also effective. Also, the formation of an amorphous silicon film
In the case of diborane (B_TwoH₆),
Boron fluoride (BF_Three), Phosphine (PH_Three) Etc.
Punt gas may be simultaneously introduced into the discharge space.

The total amorphous silicon film thus formed is 5 μm or more and 100 μm or less, more preferably 10 μm or more and 70 μm or less, and most preferably 15 μm or more and 70 μm or less.
If it is at least μm and at most 50 μm, a particularly good image as an electrophotographic photoreceptor can be obtained.

When the pressure of the reaction vessel during deposition of the amorphous silicon film is 0.06 Pa or more and 13.3 Pa or less, preferably 0.133 Pa or more and 6.65 Pa or less, discharge stability and uniformity of the deposited film are obtained. The reproducibility of film formation was good. The substrate temperature at the time of depositing the amorphous silicon film is effective in the range of 100 ° C. or more and 500 ° C. or less, but particularly 150 ° C. or more and 450 ° C. or less, preferably 200 ° C. or more and 400 ° C. or less, and most preferably 250 ° C.
As described above, an amorphous silicon film having good film quality was obtained at 350 ° C. or lower.

The substrate on which the amorphous silicon film is formed can have any shape. However, when manufacturing a photosensitive member of an electrophotographic apparatus, a cylindrical one is used. Although the size of the substrate is not particularly limited, it is generally 20 mm or more and 500 mm or less in diameter, and 10 mm or more and 1000 mm or less in length for use as a photoreceptor of an electrophotographic apparatus. <Regarding the Cleaning Process of the Present Invention> The purpose of the present invention is to remove substances adsorbed on the inner wall of a reaction vessel of a film forming apparatus that is open to the atmosphere. Therefore, the cleaning method of the present invention is applied to a film forming apparatus in which the deposited film deposited on the inner wall of the reaction vessel during film formation is removed and the reaction vessel is opened to the atmosphere.

The cleaning method of the present invention will be described in order. First, before performing the cleaning process of the present invention, a deposited film is formed as described above to form a desired film thickness to obtain an electrophotographic photosensitive member. Thereafter, the deposited film or polysilane deposited on the inner wall of the reaction vessel remaining in the reaction vessel is removed. Specifically, after taking out the electrophotographic photosensitive member on which the deposited film is formed from the reaction container (101), a cleaning substrate is put in place of the cylindrical substrate (not shown).
Then, the cleaning gas whose flow rate is controlled by the mass flow controller (109) in the same manner as when the deposited film is formed is supplied to the source gas introduction pipe (1) through the source gas inflow valve (110).
04) into the reaction vessel (101). When the internal pressure of the reaction vessel becomes stable, the reaction vessel (1) is supplied from the high-frequency power supply (105) via a matching box (not shown).
01), power is introduced to generate glow discharge. The cleaning gas introduced into the reaction vessel is decomposed by the discharge energy, and the deposited film or polysilane in the reaction vessel (101) and the exhaust pipe is cleaned. The deposited film accumulated in the reaction vessel due to the repetition of the cleaning by the plasma has a risk of peeling off during the film formation, which may cause a defect of the film.
Therefore, it is desirable to open to the atmosphere after performing cleaning by plasma several times, and to perform a cleaning method using a solvent or the like.

The manual cleaning is mainly performed after a plurality of plasma cleanings, but may be performed independently. More specifically, after exposing the reaction container (101) to the atmosphere, a solvent is contained in cleaning paper or cloth, and the inner wall of the reaction container, the substrate holder, and the surface of the gate valve are wiped and cleaned. In particular, the corners and recesses inside the apparatus, where the cleaning gas and plasma are difficult to reach, are carefully cleaned.

The solvent used for this cleaning is IPA, acetone, ethyl alcohol,
It can be selected from water and the like. The solvent used is not limited to one type, and a plurality of types may be used in combination. <Cleaning method of the present invention> The present invention proposes a cleaning method which is performed after the reaction container is opened to the atmosphere, and is performed after the inside of the reaction container (101) is opened to the atmosphere after the pre-cleaning treatment.

After the manual washing is completed, the reaction vessel (101) is set in the apparatus, and the chamber is evacuated. Then, a cleaning gas containing a ClF ₃ gas whose flow rate is controlled by the mass flow controller (109) is introduced into the reaction vessel (101) from the source gas introduction pipe (104) through the source gas inflow valve (110).

As the cleaning gas used in the cleaning method of the present invention, it is possible to use ClF ₃ gas alone, but in this case, it is difficult to adjust the cleaning time, and further, considering that the cleaning gas is converted into plasma. , ClF ₃ gas is preferably diluted with an inert gas. Here, a rare gas (He, Ne, Ar, Kr, Xe) is preferable as the inert gas. In particular, He, N
e and Ar are preferred.

The concentration of ClF _{3 in} the cleaning gas used in the cleaning method of the present invention is preferably from 10% to 70%. If the concentration of ClF ₃ is 10% or more, it has a practically acceptable cleaning effect,
When the concentration of ClF ₃ is 70% or less, a sufficient cleaning effect is obtained, and the load on the exhaust pump and the like of the film forming apparatus is small. Further, it is desirable that the concentration of ClF ₃ be 15% or more and 60% or less. Most preferably, it is 20% or more and 60% or less. Here, the concentration of ClF ₃ is expressed by the volume fraction of ClF _{3 in} the cleaning gas (ClF ₃ / (Cl
F ₃ + inert gas)). Whether the cleaning method of the present invention uses plasma,
Whether to use the stationary type or the flow type, classified according to, the stationary type is a method of introducing a cleaning gas into the reaction vessel, stopping the supply at a place under a certain pressure, and sealing and holding, The flow-through method is a method in which a cleaning gas is introduced into a reaction vessel and exhausted while maintaining the pressure at a constant pressure, that is, the cleaning gas is continuously introduced.

In the cleaning method of the present invention, the pressure of the reaction vessel is one of the parameters for changing the cleaning speed.

In the case of using plasma in the cleaning method of the present invention, a cleaning effect was observed in any region as long as the plasma was maintained within a pressure range.
In particular, 20 Pa or more and 200 Pa or less, more preferably 5 Pa or less.
At 0 Pa or more and 120 Pa or less, particularly good results were obtained with good reproducibility in terms of discharge stability and cleaning properties.

In the case where plasma is not used, the cleaning speed is lower than in the case where plasma is used. Therefore, in order to obtain the same cleaning speed as in the case where plasma is used, the ClF ₃ concentration in the cleaning gas is increased. Further, it is desirable to increase the pressure of the reaction vessel.

In the present invention, the cleaning treatment method may be such that a mixed gas of ClF ₃ gas and an inert gas is introduced into the reaction vessel and the introduced gas is sealed in the reaction vessel, _Although it is effective in any case where a plasma is formed by applying high-frequency power while introducing ₃ , the latter is practically more suitable because the reaction speed is increased and the tact is shortened.

After performing the cleaning method of the present invention, the cleaning gas remaining in the reaction vessel is exhausted,
Subsequently, a deposited film can be formed. However,
In order to completely remove the residual cleaning gas in the reaction vessel, it is desirable to replace the reaction vessel with an inert gas as shown below. The replacement process of the present invention <substitution treatment after cleaning>, wherein the reaction the reaction vessel with N ₂ or an inert gas at a constant flow rate into the container is introduced a certain time so as to 26.6 Pa, the pressure If it becomes, stop introducing inert gas,
The method in which the inert gas is introduced into the reaction vessel instantly after leaving it for a certain period of time, or when the reaction vessel reaches 26.6 Pa, the supply of the inert gas is stopped immediately, and the inert gas is exhausted from the reaction vessel. Any of repeating the method several times is effective.

Here, as the inert gas for replacement,
N ₂ , Ar, Ne and the like are preferably used.

In the present invention, the heating means for the substrate may be any heating element of a vacuum specification, and more specifically, an electric resistance heating element such as a winding heater of a sheath heater, a plate heater, a ceramic heater, or a halogen. Examples of the heating element include a heat radiation lamp heating element such as a lamp and an infrared lamp, and a heating element using a liquid or a gas as a heating medium and a heat exchange unit.
As the surface material of the heating means, metals such as stainless steel, nickel, aluminum and steel, ceramics, heat-resistant polymer resin and the like can be used. In addition, other methods such as providing a dedicated heating vessel separately from the reaction vessel, heating, and then transporting the substrate into the reaction vessel in a vacuum can be used. It is possible in the present invention to use the above means alone or in combination.

[0047]

EXAMPLES Examples for demonstrating the effects of the present invention will be described below, but the present invention is not limited thereto.

(Example 1) In the deposition film forming apparatus of the chemical vapor deposition method (hereinafter referred to as CVD method) shown in FIG.
The cylindrical substrate on which the blocking electrophotographic photosensitive member having the layer configuration shown in FIG. 2A was formed according to the film forming conditions shown in Table 2 was made of aluminum and had a diameter of 108 mm, a length of 358 mm, and a wall thickness of 5 mm. is there.

Continuously, after forming the element type electrophotographic photosensitive member layer on the surface of the cylindrical substrate for 20 cycles, the reaction vessel is returned to the atmospheric pressure, and the inside of the reaction vessel is manually operated by using a solvent. Cleaning was done.

The solvent used here was manufactured by Kishida Chemical Co.
2-propanol (IPA), cleaning with solvent
After the completion of, the dummy base is placed in a predetermined position,
The reaction vessel is evacuated and the deposition film can be formed again.
Source gas introduction valve when it reaches airness (0.13 Pa)
Through 110, ClF_ThreeCleaning gas containing
Is introduced into the reaction vessel 101, and the reaction vessel 101
When pressure is reached, high-frequency power (frequency: 13.56 MH
z, RF power 1.8 kW) to apply ClF _ThreeNo
Rasma occurred. Table 1 shows the cleaning conditions of this example.
The matter was put together. ClF_ThreeCleaning with plasma
After the completion, the degree of vacuum in the reaction
Remaining inside the reaction vessel
Gas (ClF_Three+ Ar) -derived components were evacuated.

Thereafter, the inside of the reaction vessel was replaced by repeating the intermittent method five times using N ₂ gas. More specifically, when the N ₂ gas is supplied into the reaction vessel to reach 26.6 Pa, the supply of the N ₂ gas is stopped and the state is left for 30 seconds. Thereafter, the supply of the N ₂ gas is stopped, and the reaction vessel is evacuated. When the reaction vessel reaches a degree of vacuum (0.13 Pa) at which a deposited film can be formed, the N ₂ gas is supplied again. This operation was repeated five times.

Thereafter, an amorphous silicon deposited film is formed on the cylindrical substrate of the same material and dimensions used for film formation before cleaning under the same conditions as before cleaning.
A blocking type electrophotographic photosensitive member having the layer configuration shown in (A) was prepared. In FIG. 2A, reference numeral 201 denotes a conductive substrate, 202 denotes a charge injection blocking layer, 203 denotes a photoconductive layer, and 204 denotes a surface protective layer.

The electrophotographic characteristics of the thus produced electrophotographic photosensitive member were evaluated as follows.

The copying machine manufactured by Canon Inc., which was modified so that the process speed of the produced electrophotographic photosensitive member could be arbitrarily changed within the range of 200 to 800 mm / sec for experiments,
P6060, a voltage of 6 to 7 kV was applied to the charger to perform corona charging, an image was formed on transfer paper by a normal copying process, and electrophotographic characteristics and image quality were evaluated by the following procedure. The electrophotographic photoreceptors thus manufactured under the same manufacturing conditions were evaluated, and the results of evaluation of each evaluation item are shown in Table 3.

(Evaluation of Appearance) The appearance of the produced electrophotographic photosensitive member was observed, and the presence of defects (hereinafter, abbreviated as “scratch flower”) in the deposited film in which abnormally grown deposited films were collected was visually confirmed. . ◎: Very good ○: Very small and difficult to confirm clearly △ No problem △: Confirmable but light. ×: clearly visible and quite large (evaluation of scratched flower image) An image with the most image defects in the image sample obtained when the process speed was changed and the entire halftone original and text original were copied on the platen A sample was selected and evaluated. As an evaluation method, the image sample was observed with a magnifying glass, and evaluation was performed based on the state of white spots within the same area. ◎… very good ○ ‥ ・ Some small white spots, but very small and no problem. △ ・ ‥ There are slight white spots on the entire surface, but there is no problem in character recognition. × ‥ ・ Some characters are difficult to read due to many white spots <Image deletion evaluation> Canon test chart (part number FY9-9058) consisting of whole characters on a white background Light is radiated at an exposure amount twice as large as that described above to make a copy. The image thus obtained was observed, and it was evaluated whether the thin lines on the image were connected without interruption by the following four steps. In addition, when there was unevenness on the image, evaluation was made at the worst part in the entire image area. ◎: “Good” ○: “Partially interrupted” △: “Many interrupts but legible as characters, no practical problem” ×: “Many interrupts, difficult to read as characters, practically problematic”

[0056]

[Table 1]

[0057]

[Table 2]

[0058]

[Table 3]

From the above results, good results were obtained by performing the cleaning treatment after opening to the atmosphere.

(Comparative Example) An electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that the cleaning treatment was not performed after opening to the atmosphere, and the result of evaluation by the same method was used as a comparative example. It is shown in Table 3.

Example 2 In this example, as shown in Table 1, an electrophotographic photosensitive member was prepared in the same manner as in Example 1 except that no plasma of ClF ₃ was used during the cleaning process. Was evaluated by the following method. That is, in this embodiment, the cleaning gas was continuously supplied while the reaction container was evacuated so as to keep the internal pressure of the reaction container constant.

Hereinafter, cleaning that does not generate plasma as in this embodiment is referred to as non-plasma. Table 3 shows the results. As is clear from Table 3, even in the non-plasma treatment, the same cleaning effect as in Example 1 was obtained.

Example 3 In this example, after the reaction vessel was opened to the atmosphere and cleaned with a solvent, a cleaning gas (ClF ₃ + Ar) was introduced into the reaction vessel at a constant pressure as shown in Table 1. An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that it was satisfied, and evaluated in the same manner.

That is, in this embodiment, if the cleaning gas is introduced until the reaction container reaches a predetermined internal pressure, the cleaning is performed by leaving the reaction container without exhausting the reaction container. Table 3 shows the results.

As is clear from Table 3, the same effect was obtained even when the reactor was filled with ClF ₃ by the non-plasma treatment.

Example 4 As shown in Table 1, Example 3
An electrophotographic photoreceptor was prepared in the same manner as in Example 1 except that the cleaning was performed using plasma during the cleaning process.
Evaluation was performed in the same manner. Table 3 shows the results.

As is clear from Table 1, the same effect was obtained by sealing ClF ₃ in the reaction vessel and using plasma.

(Embodiment 5) VHF plasma C shown in FIG.
After the reaction vessel was opened to the atmosphere using a VD apparatus, the reaction vessel was cleaned in the same manner as in Example 1, and then under the conditions shown in Table 4, an electrophotograph of the layer configuration shown in FIG. A photoreceptor was made. In FIG. 2B, 201 is a conductive substrate, 202 is a charge injection blocking layer, and 203-1 and 203-
Reference numeral 2 denotes a photoconductive layer having a different composition, and reference numeral 204 denotes a surface protective layer. The deposited film thus produced was evaluated in the same manner as in Example 1.

[0069]

[Table 4]

[0070]

According to the present invention, as described above, when forming a deposited film immediately after the reaction vessel is opened to the atmosphere, the inside of the reaction vessel is evacuated from atmospheric pressure to a degree of vacuum capable of forming a deposited film, By cleaning the inside of the reaction container with ClF ₃ before forming the deposited film, the adsorbed substances such as oxygen and water and the remaining solvent in the reaction container are removed, and the solvent is always stabilized when the deposited film is formed. A highly reproducible reaction vessel can be obtained.

Further, according to the deposited film forming method of the present invention,
It is possible to mass-produce high-priced electrophotographic photosensitive members with high yield.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a deposited film manufacturing apparatus of the present invention.

FIG. 2A is a schematic view of a layer configuration of an electrophotographic photosensitive member. FIG. 2B is a schematic diagram of a layer configuration of the electrophotographic photosensitive member.

FIG. 3 is an overall configuration diagram of a deposition film manufacturing apparatus using VHF.

[Explanation of symbols]

 101, 301... {Reaction vessel 102, 201, 302}... Conductive substrate 103, 303...} Heater 104... Source gas introduction tube 304... VHF electrode and source gas introduction tube 105. , 109... Mass flow controller 106... Base plate 306... {Electricity space 107}... Gate valve 108... {Conductive substrate holder 308...} Driving device 110.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hideaki Matsuoka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kazuhiko Takada 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon (72) Inventor Koji Hitsuishi 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term in Canon Inc. (Reference) 2H068 DA23 EA24 EA30 EA47 4K029 CA01 CA05 DA01 FA09 4K030 AA06 AA17 BA30 CA02 CA16 DA06 KA08 LA17 5F045 AA08 AB02 AB04 AB05 AC16 AC17 AD04 AD05 AD06 AD07 AD08 AE01 AE13 AE15 AE17 AE19 BB15 CA16 DQ10 EB06 EH12 EK07 EM10

Claims (7)

[Claims] 1. A method for cleaning a film forming apparatus for forming a deposited film on a substrate in a reaction vessel under a pressure lower than the atmospheric pressure, the method comprising: (1) removing the deposited film adhered to the inner wall of the reaction vessel; And (2) exposing the reaction vessel to the atmosphere; and (3) cleaning the inner wall of the reaction vessel with a cleaning gas containing at least ClF ₃ or a plasma of the cleaning gas,
A method for cleaning a deposition film forming apparatus, wherein the step (3) is performed last of the three steps. 2. The film forming apparatus according to claim 1, wherein the apparatus for forming a film on the substrate under a pressure lower than the atmospheric pressure is an apparatus for forming a film on the substrate by a chemical vapor deposition method. Cleaning method. 3. The method for cleaning a film forming apparatus according to claim 1, wherein the apparatus for forming a film on a substrate under a pressure lower than the atmospheric pressure is an apparatus for forming a film on a substrate by a sputtering method. 4. The method for cleaning a film forming apparatus according to claim 1, wherein in the step (3), the cleaning gas is introduced into the reaction vessel in a stationary or flowing manner. 5. The method according to claim 1, wherein in the step (1), the deposited film attached to the inner wall of the reaction vessel is removed by plasma. 6. A method for forming a deposited film, wherein the method for cleaning a film forming apparatus according to claim 1 performs the cleaning of the reaction vessel, and subsequently forms a deposited film on a substrate. 7. After cleaning the reaction container by the method for cleaning a film forming apparatus according to claim 1,
A method of forming a deposited film, wherein the reaction vessel is replaced with an inert gas, and thereafter, a deposited film is formed on the substrate.