JP2007070695A - Method for forming deposited film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for forming a deposited film, which is excellent in productivity and by which the generation of the exfoliation of a deposited film deposited on the inner wall of a dielectric material constituting a portion of a reaction vessel can be suppressed even when the dielectric material is used repeatedly by efficiently removing the deposited film deposited on the inner wall. <P>SOLUTION: In the method for forming the deposited film, comprising arranging a base body in the reaction vessel at least a portion of which is constituted of the dielectric material and which can be evacuated, and decomposing a raw material gas supplied into the reaction vessel by high-frequency power to form a deposited film containing a first layer comprising a non-single crystal film containing nitrogen atom or carbon atom in the matrix of silicon atom on the base body, the deposited film deposited on the part of the dielectric material of the reaction vessel is removed by liquid etching in a pre-treatment process and by liquid honing in a post-treatment process after completion of forming the deposited film. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a deposited film forming method used for forming a semiconductor device, an electrophotographic photoreceptor, an image input line sensor, a photographing device, a photovoltaic device, and the like by plasma CVD.

  As one of the deposited film forming methods, a CVD method using low-temperature plasma has attracted attention. In this method, the inside of the reaction vessel is depressurized to a high vacuum, the source gas is introduced into the reaction vessel, the discharge power is applied, the source gas is decomposed by glow discharge, and deposited on a substrate disposed in the reaction vessel. A method for forming a film, which is applied to, for example, formation of an amorphous silicon film (a-Si film).

  Usually, when a deposited film is formed on a substrate placed in a reaction vessel, a by-product adheres to the inner wall of the reaction vessel or a member disposed in the reaction vessel. In general, this by-product easily peels off, adheres to the substrate, contaminates the substrate, and may cause a serious defect in the deposited film.

  Therefore, after the deposited film is formed, by-products adhering to the inner wall of the reaction vessel and the members arranged in the reaction vessel are removed, and then a new substrate is placed in the reaction vessel and deposited on the substrate. Forming a film is a desirable production method, and proposals have been made regarding the removal of the by-products.

  Specifically, a method is disclosed in which a reaction container made of an insulating member after the deposition film is formed is removed, and a by-product attached to the inner wall of the reaction container is removed by liquid honing or liquid etching after the substrate is removed. (For example, refer to Patent Document 1).

  In addition, after forming the deposited film, the insulating member constituting a part of the reaction vessel is removed from the deposited film forming apparatus, and the by-product adhering to the insulating member is removed by liquid honing or liquid etching. A method of performing damage inspection is disclosed (for example, see Patent Document 2).

Further, after removing the deposited film adhering to the substrate holding part or auxiliary part after the deposited film is formed in the etching process, the residue in the etching process is removed through each process in the order of the cleaning process, the drying process, and the cooling process. Is disclosed (for example, see Patent Document 3).
JP 2000-077339 JP 2002-317268 A JP 2002-129333 A

  In recent years, digital electrophotographic devices and color electrophotographic devices, which have been widely used, often make copies of not only text originals but also photographs, pictures, design drawings, etc., and thus image density unevenness can be reduced more than before. It has come to be required. At the same time, structural defects such as spherical protrusions that cause image defects such as white spots or black spots on the image are required to be reduced more than ever.

  Such a structural defect is one in which the deposited film grows abnormally due to foreign matters such as dust adhering to the substrate before the deposited film is formed. For this reason, the substrate before film formation is strictly cleaned, and transported into a reaction vessel in a dust-controlled environment such as a clean room, so as to prevent dust from adhering to the substrate as much as possible.

  Further, when a deposited film is formed on a substrate placed in the reaction vessel, a powdery by-product called polysilane adheres to the inner wall of the reaction vessel. This by-product easily peeled off from the wall surface of the reaction vessel, and sometimes adhered to the substrate during the formation of the deposited film and abnormally grew.

  As a method for forming such a deposited film in which the by-product attached to the wall of the reaction vessel does not become powdery, the inside of the reaction vessel is decompressed to 13.4 Pa or less, preferably 10 Pa or less, and a high frequency of 50 MHz to 250 MHz. There is a technique for forming a by-product formed in the reaction vessel into a film by using electric power.

  However, in the method for forming a deposited film using a reaction vessel at least partially composed of a dielectric material, a minute film is formed on the deposited film formed in the reaction vessel during the formation of the deposited film due to internal stress in the film. In some cases, peeling occurs and diffuses as a film piece in the discharge space, and a part of the film adheres to the substrate and grows abnormally.

  In order to prevent the deposited film formed in the reaction vessel from peeling off, the surface of the reaction vessel inner wall and the components in the reaction vessel are roughened with a ceramic material with a large surface energy. A coating process has been applied.

  However, since it is difficult to roughen a wide area uniformly in the roughening treatment of the member, partial film peeling may occur. Furthermore, when the surface of the member is coated with a ceramic material, the adhesion of the film is good in the initial state, but the durability is fatigued due to repeated use, and the ceramic material itself may peel off from the member. Improvement in cost is desired.

  In addition, means for preventing the film from peeling off by covering the inside of the reaction vessel with an adhesive layer before film formation of the photoreceptor is used. If the adhesion layer formed by plasma CVD is removed by etching or honing, the adhesion layer can be provided every time the deposited film is formed, so there is no concern about durability. As such an adhesion layer, for example, silicon nitride or silicon carbide can be easily formed by plasma CVD and is known as a film having high adhesion, and is a material that has a proven record as a photoreceptor.

  However, the adhesion layer improves the adhesion, but the deposited film deposited on the inner wall of the reaction vessel or the member disposed in the reaction vessel after the formation of the deposited film is not sufficiently removed, and the residue of the adhesion layer remains. May end up.

  For example, in the case of dry etching in which the deposited film is gasified and removed with a halogen compound such as carbon tetrafluoride or chlorine trifluoride, a powdery residue remains in the concave and convex recesses on the inner wall surface of the reaction vessel. The residue may not be completely removed by washing.

  In addition, liquid etching using a chemical solution or liquid honing in which a liquid containing an abrasive is jetted has a long processing time, and further processing unevenness occurs, and a residual film may exist in the concave and convex recesses on the inner wall surface of the reaction vessel. is there.

  The powdery residue and the residual film remaining in the recesses impair the adhesion of the deposited film, and minute film peeling may occur when the deposited film is formed next time.

  Furthermore, in the case of liquid etching using a chemical solution, in addition to the problem of the residual film, a long-time treatment is required to wash the water to such an extent that contamination does not occur, which may reduce productivity.

  Even if the first layer for forming a deposited film using a reaction vessel at least partially made of a dielectric material is an adhesion layer made of, for example, silicon nitride or carbonized silicon, the inner wall surface of the reaction vessel Therefore, there is a demand for a method capable of efficiently removing the deposited film including the adhesion layer deposited on the substrate.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a deposited film forming method excellent in productivity that does not cause peeling of a deposited film even when a dielectric material is repeatedly used. There is.

  In order to achieve the above object, the present invention has a base placed in a depressurizable reaction vessel at least partially made of a dielectric material, and decomposes the raw material gas supplied into the reaction vessel with high frequency power, In the deposited film forming method for forming a deposited film including a first layer formed of a non-single crystalline film containing a silicon atom as a base and containing a nitrogen atom or a carbon atom on the substrate, the formation of the deposited film is completed. The deposited film deposited on the dielectric material portion of the reaction vessel later is removed by a pretreatment step by liquid etching and a posttreatment step by liquid honing.

  As a result of intensive studies to achieve the above object, the present inventors have found that a non-single crystal containing a nitrogen atom or a carbon atom based on a silicon atom on the inner wall of a reaction vessel at least partially composed of a dielectric material As a method for removing the deposited film deposited on the dielectric material portion of the inner wall of the reaction vessel after forming the deposited film including the first layer formed by the film, post-processing by liquid honing after performing a pre-processing step by liquid etching It has been found that it can be efficiently removed by sequentially performing the steps.

  In the formation of a deposited film, there is a case where a non-single crystal film containing silicon atoms as a base and containing 10% to 30% nitrogen atoms or 20% to 40% carbon atoms is formed in the first layer for the purpose of improving adhesion. is there. As a suitable analysis method for the content of nitrogen atoms and carbon atoms, ESCA analysis can be mentioned.

  The first layer is preferably silicon nitride containing 10 atom% or more and 30 atom% or less of nitrogen atoms, or silicon carbide containing 20 atom% or more and 40 atom% or less of carbon atoms, and further laminating the silicon nitride and the silicon carbide. Even if the effect as an adhesion layer is acquired.

  If the nitrogen content of the silicon nitride film is less than 10 atomic%, sufficient adhesion may not be ensured, and if it exceeds 30 atomic%, the residual potential may increase and good electrophotographic characteristics may not be obtained.

  Also, if the carbon content of silicon carbide is less than 20 atomic%, sufficient adhesion may not be ensured, and if it exceeds 40 atomic%, the residual potential may increase and good electrophotographic characteristics may not be obtained. .

  Either the silicon nitride film or the silicon carbide film having excellent adhesion or the laminated film of the silicon nitride film and the silicon carbide film is used for the first layer, and a part thereof is deposited on the inner wall of the reaction vessel made of a dielectric material. In this case, while improving the adhesion, it may be difficult to efficiently remove the deposited film.

  As a result of intensive investigations on an efficient removal method of the deposited film, as a pretreatment process, liquid etching using a chemical solution is used to remove the majority of the deposited film and to treat the remaining film as well. Liquid etching causes an unstable state floating from the inner wall of the reaction vessel made of a dielectric material, resulting in a state where adhesion is reduced and can be easily peeled off.

  Next, the residual film that has been easily peeled off by liquid honing can be removed by the physical action of liquid honing that ejects the liquid containing the abrasive in the post-processing step.

  Further, by performing post-processing by liquid honing, it is possible to reliably remove the chemical solution remaining in the reaction vessel that is not completely removed even by cleaning after the liquid etching step, and the next deposited film formation In this case, it is possible to form a deposited film without contamination.

  In other words, by performing processing in the order of pre-processing by liquid etching and then post-processing by liquid honing, it becomes possible to efficiently perform processing in a state that is not affected by contamination without causing processing unevenness in a short time. .

  According to the present invention, even if the dielectric material is repeatedly used by efficiently removing the deposited film formed on the inner wall of the dielectric material that constitutes a part of the reaction vessel, the deposited film does not peel off. A method for forming a deposited film having excellent productivity can be provided.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram for explaining a layer configuration of an electrophotographic photosensitive member that can be produced by the present invention.

  FIG. 1A shows an electrophotographic photosensitive member in which a charge injection blocking layer 104 that also serves as an adhesion layer, a photoconductive layer 102, and a surface layer 103 are sequentially laminated on a substrate 101. The photoconductive layer 102 is formed of a non-single-crystal material containing silicon atoms as a base and containing at least hydrogen, and the surface layer 103 is formed of a non-single-crystal material containing hydrogen atoms and containing at least one of silicon atoms and carbon atoms. In addition, it has a capability of holding a visible image in an electrophotographic apparatus.

  FIG. 1B shows a layer structure in the case where the charge injection blocking layer 104 which also serves as an adhesion layer in addition to the layer structure of FIG. The charge injection blocking layer 104 also serving as the adhesion layer may be continuously changed in composition.

As a material for the charge injection blocking layer 104 and the adhesion layer 105 which also serve as the adhesion layer, for example, a non-single crystal material containing at least silicon atoms and containing carbon, nitrogen, oxygen, hydrogen, fluorine, boron, etc., or at least carbon atoms. Non-single crystal carbon material containing skeleton, nitrogen, oxygen, hydrogen, fluorine, boron, etc., or III-V group compounds such as boron nitride, aluminum nitride, metal oxides such as Al ₂ O ₃ , ZnO, InO ₂ However, a material having good affinity with the metal (aluminum or stainless steel) as a base and having good affinity with the photoconductive layer is preferable.

  In particular, a non-single-crystal silicon carbide film containing at least silicon atoms and carbon atoms and a non-single-crystal silicon nitride film containing at least silicon atoms and nitrogen atoms are preferable, and a non-single-crystal silicon nitride film is most preferable. Specifically, amorphous silicon nitride (a-SiN), hydrogenated amorphous silicon nitride (a-SiN: H), hydrogenated amorphous silicon nitride containing halogen (a-SiN: H: X) And may partially contain microcrystals.

The source gas that is effectively used to form the charge injection blocking layer 104 that also serves as the adhesion layer and the adhesion layer 105 includes nitrogen such as nitrogen, nitride, fluorinated nitrogen, and azide, including nitrogen atoms. An oxide is mentioned. Specifically, nitrogen (N ₂ ), ammonia (NH ₃
), Hydrazine (H ₂ NNH ₂ ), nitrogen trifluoride (NF ₃ ), nitrogen tetrafluoride (N ₂ F ₄ ), hydrogen azide (HN ₃ ), ammonium azide (NH ₄ N ₃ ), etc. Be Examples of those containing silicon atoms include silanes such as SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ , Si ₄ H ₁₀ , and halogen-substituted silicon hydrides obtained by substituting hydrogen of silanes with halogen. .

In addition to these gases, hydrogen (H ₂ ), helium (He), neon (Ne), argon (Ar), or the like may be appropriately mixed as a diluent gas. For the purpose of improving electrical characteristics, a small amount of valence electron control gas such as diborane (B ₂ H ₆ ) or phosphine (PH ₃ ) may be added.

  Any source gas and mixing ratio may be used as long as a film having desired adhesion can be obtained using these gases.

  In addition, any pressure may be used as the pressure at the time of producing the charge injection blocking layer 104 and the adhesion layer 105 that also serve as the adhesion layer, as long as the desired adhesion can be obtained. It is easy to improve the property. The cause is unknown, but it is thought that the behavior of active species in the plasma changes and the bonding of the deposited film changes. Strictly speaking, the numerical value of the pressure varies depending on the frequency, but at a high frequency of 50 to 250 MHz, it is preferably 1.3 Pa or more, more preferably 2 Pa or more. Further, the upper limit is preferably 13.4 Pa or less, more preferably 10 Pa or less in view of discharge stability.

  Next, an outline of a method for producing an electrophotographic photosensitive member using the production apparatus shown in FIG. 2 will be described below.

  FIG. 2 is a schematic view showing an example of an electrophotographic photoreceptor manufacturing apparatus applicable to the present invention. Six high-frequency electrodes 204 are installed on the outer periphery of the reaction vessel 202 at equal intervals, and 6 in the reaction vessel 202. This is a mass production type manufacturing apparatus in which a cylindrical base 201 is installed.

  2A is a schematic cross-sectional view, and FIG. 2B is a schematic cross-sectional view taken along a cutting line A-A ′ in FIG.

  An exhaust port 207 is provided on the bottom surface 216 of the cylindrical reaction vessel 202, the exhaust port 207 is connected to an exhaust pipe 217, and the other end of the exhaust pipe 217 is connected to an exhaust device (not shown).

  In the reaction vessel 202, six cylindrical substrates 201 on which deposited films are formed are arranged at equal intervals on the same circumference in a state of being placed on the substrate support 206. In addition, six gas introduction pipes 203 for introducing gas are installed at equal intervals on the same circumference outside the circle where the cylindrical substrate 201 is arranged.

  After the high frequency power is supplied from the first high frequency power source 208 and the second high frequency power source 209 through the matching box 205, the high frequency power is supplied into the reaction vessel 202 from the high frequency electrode 204.

  The power branch plate 213 is installed in a shield 214 that substantially confines electromagnetic waves while being electrically insulated from the shield 214. That is, it has the structure fixed to the reaction apparatus through the insulator. Furthermore, in order to improve the vacuum processing stability in the initial stage of discharge, the power branch plate 213 and the high-frequency electrode 204 may be connected via a capacitor.

  In order to efficiently introduce the high-frequency power emitted from the high-frequency electrode 204 into the reaction vessel 202, ceramic which is a dielectric is used on the side wall of the cylindrical reaction vessel 202. Specific examples of the ceramic material include alumina, titanium dioxide, aluminum nitride, boron nitride, zircon, cordierite, zircon cordierite, silicon oxide, and beryllium mica-based ceramics. Of these, alumina, aluminum nitride, and boron nitride are preferable from the viewpoint of suppression of impurity contamination during heat treatment and heat resistance.

  The apparatus shown in FIG. 2 has a configuration in which a plurality of high-frequency power supplies are connected for the purpose of improving unevenness in the film thickness and film quality of the deposited film.

  In this manner, standing waves on the electrode or the conductive substrate can be suppressed by supplying high frequencies having a plurality of frequencies superimposed on the same electrode from the same direction.

The high-frequency power sources 208 and 209 are related to each other in the oscillation frequency, for example, the high-frequency power source 208 supplies the first high-frequency power (frequency f1, power value P1), and 209 the second high-frequency power (frequency f2). , When the second high-frequency power source supplying power value P2) is used,
50 MHz ≦ f2 <f1 ≦ 250 MHz
0.1 ≦ P2 / (P1 + P2) ≦ 0.9
Therefore, the balance is most preferable and preferable from the viewpoint of deposition rate, characteristics, and unevenness suppression. In order to perform uniform film deposition with a large area at high speed, it is most preferable to use a technique of superimposing two high frequencies in the above-described range.

  The first high frequency power supply 208 may be provided with a high pass filter having a cutoff frequency characteristic lower than f1 and higher than f2. Similarly, the second high frequency power supply 209 may be provided with a low pass filter having a cutoff frequency characteristic higher than f2 and lower than f1. Higher frequency selectivity is more preferable because the other power that wraps around each high-frequency power source can be reduced.

The power range is 0.2 ≦ P2 / (P1 + P2) ≦ 0.7.
Is more preferable.

  Next, an outline of production of an electrophotographic photoreceptor using the apparatus of FIG. 2 will be described below.

  A cylindrical substrate 201 made of an aluminum material is installed in a reaction vessel 202 made of a ceramic material that is opened to the atmosphere, and the air is exhausted to an exhaust pipe 217 via an exhaust port 207 by an exhaust device (not shown) (for example, a vacuum pump). And the inside of the reaction vessel 202 is exhausted. Subsequently, a substantially non-film-forming heating gas is supplied from the gas introduction pipe 203 to the reaction vessel 202. At this time, the pressure in the reaction vessel 202 is adjusted by adjusting the degree of opening of the exhaust pipe 217 by a pressure adjusting valve 218 provided in the exhaust pipe 217.

  When the flow rate of the substrate heating gas supplied into the reaction vessel 202 reaches a predetermined flow rate and the pressure in the reaction vessel 202 becomes stable at a predetermined value, the cylindrical substrate 201 is heated by a heater (not shown). Is heated to a predetermined temperature of about 200 ° C. to 300 ° C., and it is confirmed that the cylindrical substrate 201 is stabilized at the predetermined temperature.

  Conditions such as the pressure in the reaction vessel 202 and the type of gas in the heating step may be appropriately selected according to the substrate heating temperature, the heating time, and the like.

Regarding the type of gas, considering the ease of handling, cost, damage to the cylindrical substrate 201, etc., it is desirable to use a gas such as H ₂ , He, Ar, N ₂ , in which case two or more gases are used. A mixed gas may be used. In particular, among these gases, H ₂ and He are desirable because of their excellent thermal conductivity.

  Next, when the heating process reaches a predetermined time, the gas is switched from the heating gas to the deposited film forming raw material gas.

  After confirming that the flow rate of the deposition film forming raw material gas becomes the set flow rate and that the pressure in the reaction vessel 202 is stabilized at a desired pressure, high frequency power is supplied from the high frequency power sources 208 and 209 via the matching box 205 to the high frequency. Supply to electrode 204.

  Thereby, high frequency power is introduced into the reaction vessel 202, glow discharge occurs in the reaction vessel 202, the source gas is excited and dissociated, and an adhesion layer or adhesion layer is formed on the entire region inside the reaction vessel and the cylindrical substrate 201. A charge injection blocking layer is also formed.

  After the formation of the desired film thickness, the same operation is repeated, the source gas and the high frequency power are continuously switched, and the photoconductive layer is sequentially formed until the desired film thickness is obtained, and then the high frequency power is supplied. Next, the supply of the raw material gas is stopped.

  Next, the surface layer is formed by the following procedure.

  The inside of the reaction vessel 202 is evacuated, and the source gas necessary for the surface layer is introduced into the reaction vessel 202. After confirming that the flow rate of the source gas is the set flow rate and that the pressure in the reaction vessel 202 is stable, the high frequency power is supplied from the high frequency power sources 208 and 209 to the high frequency electrode 204 via the matching box 205.

  As a result, high frequency power is introduced into the reaction vessel 202, plasma is generated in the reaction vessel 202, the source gas is excited and dissociated to form a surface layer to a desired film thickness, and then the supply of high frequency power is stopped. Subsequently, the supply of the raw material gas is stopped.

  During the formation of the deposited film, the cylindrical substrate 201 is rotated at a predetermined speed by the motor 211 via the rotating shaft 210, whereby the deposited film is formed over the entire surface of the cylindrical substrate 201.

Next, the source gas remaining in the reaction vessel 202 is replaced by supplying Ar gas into the reaction vessel 202. When the temperature in the reaction vessel 202 reaches room temperature, N2
The inside of the reaction vessel 202 is vented with gas or Ar gas to open the atmosphere.

  Further, after the cylindrical substrate 201 on which the deposited film is formed is taken out, the reaction vessel 202 is removed from the vacuum processing apparatus 200, and the process proceeds to the deposited film removal step on the inner wall of the reaction vessel 202.

  In the deposited film removing step, the temperature of an alkaline solution having a concentration of about 20% is controlled in the range of 60 ° C to 80 ° C.

  A reaction vessel made of an alumina material is immersed in an etching bath containing an alkaline solution whose temperature is controlled in the range of 60 ° C. to 80 ° C., and after the deposited film is etched for 1 hour, the reaction is performed with pure water. The solution is washed and the pretreatment process by liquid etching is finished.

  As the alkaline solution, an aqueous sodium hydroxide solution, an aqueous potassium hydroxide solution or the like is suitable.

Next, 392.3 kPa (4 kgf / cm ² ) to 784. liquid containing abrasives in a ratio of water to abrasives of 3: 1 to 5: 1 with respect to the inner wall surface of the reaction vessel after the liquid etching step was completed. The liquid honing process of ejecting with 5 Pa (8 kgf / cm ² ) compressed air completely removes the residual film of the liquid etching process, and the liquid honing process is completed through a cleaning process and a drying process with pure water.

  The abrasive can be a polygonal material such as SiC or alumina, or a spherical material such as iron, SUS, or glass. However, damage to the reaction vessel caused by repeated use over a long period of time, uneven wear on the reaction vessel wall surface, etc. In view of non-uniformity of the surface roughness due to the above, a material having a low hardness is preferable to the material constituting the reaction vessel. Further, although the center particle size of the abrasive varies depending on the material of the abrasive, an effective center particle size may be selected in the range of the center particle size of 30 μm to 250 μm.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by these.

  After the cylindrical aluminum cylinder 201 having a diameter of 80 mm and a length of 358 mm is installed in the reaction vessel 202 made of the alumina ceramic material of the vacuum processing apparatus 200 shown in FIG. 2, the production conditions shown in FIG. Six electrophotographic photoreceptors having a layer structure were prepared.

  Next, the reaction vessel 202 made of alumina ceramic material was removed from the vacuum processing apparatus 200, and liquid etching and cleaning with pure water were sequentially performed with a 24% concentration sodium hydroxide solution whose temperature was controlled at 70 ° C. to complete the pretreatment process.

Next, the residual film on the inner wall surface of the reaction vessel 22 made of the alumina ceramic material after the pretreatment process was removed by liquid honing, and the post-treatment process was completed by washing with pure water and drying. In addition, liquid honing used a spherical glass material (GB-AC manufactured by Toshiba Ballotini Co., Ltd.) having a center particle diameter of 200 μm as an abrasive. The ratio of water to abrasive was 3: 1, and the ejection pressure was 588.4 kPa (6 kgf / cm ² ).

  A deposition film forming process, a liquid etching process, a pure water cleaning process, a liquid honing process, a pure water cleaning process, and a drying process are repeated for the reaction vessel 202 made of the alumina ceramic material, and the electrophotographic photosensitive member is formed under the conditions shown in Table 1. Ten lots were produced, and the following evaluation was performed on the last lot (six electrophotographic photosensitive members).

  The surface of the produced six electrophotographic photosensitive members was observed with a microscope. Select 4 directions at 90 degree intervals in the circumferential direction, select 17 points at 2 cm intervals in the axial direction, 68 points in total in 4 rows in the circumferential direction, and count the number of spherical protrusions with a diameter of 10 μm or more in a 50 times field of view. Counting was performed, and the average value of the six electrophotographic photosensitive members was defined as the value of the number of spherical protrusions.

Next, the residual potential was measured for six electrophotographic photosensitive members. The residual potential was measured using a Canon iR5000 modified for evaluation, and the center of the electrophotographic photosensitive member was not irradiated with image exposure by a potential sensor of a surface potentiometer (Model 344 manufactured by TREK) set at the developer position. After adjusting the current value of the charger so that the surface potential is 400 V (dark potential), the surface potential (bright potential) when image exposure (semiconductor laser with a wavelength of 655 nm) is irradiated at 1.0 μJ / cm ² is measured. The average value of the six electrophotographic photosensitive members was defined as the residual potential.

  In addition, after producing the 10 lots of electrophotographic photoreceptors, 6 analytical electrophotographic photoreceptors were prepared in which only the charge injection blocking layer 104 serving also as the adhesion layer shown in Table 1 was deposited in the same process. One of the electrophotographic photoconductors is arbitrarily selected, the center is cut into a sample of 1 cm × 1 cm size, and the nitrogen content ratio N / (Si + O + N) of the charge injection blocking layer 104 also serving as the adhesion layer is evaluated by ESCA measurement did.

The results are shown in Table 2 together with Comparative Example 1. The evaluation of the spherical protrusion was N2 of Comparative Example 1.
This is a relative comparison with the number of spherical protrusions of a lot produced at a flow rate of 50 ml / min (Normal) as 100. Therefore, the smaller the numerical value, the fewer the spherical protrusions, and the better.

<Comparative Example 1>
A deposition film forming process, a liquid etching process, a pure water cleaning process, and a drying process are performed on the reaction vessel 202 made of an alumina ceramic material under the same conditions as in Example 1 except that the honing process is not performed using the apparatus of FIG. Then, 10 lots of electrophotographic photosensitive members were produced, and the last 1 lot (six electrophotographic photosensitive members) was evaluated.

  The six produced electrophotographic photosensitive members were evaluated for spherical protrusions and residual potential in the same manner as in Example 1. The results are shown in Table 2 together with Example 1.

※Ｎ₂ ガスの流量は５０，１００，３００，５００，５５０［ｍｌ／ｍｉｎ（ｎｏｒｍａｌ）］の各流量パターンで作成。

* N ₂ gas flow rate is created with each flow rate pattern of 50, 100, 300, 500, 550 [ml / min (normal)].

（球状突起数は窒素含有量が５原子％の比較例を１０とした時の相対値）
以上の結果、何れの窒素含有量でもアルミナセラミック材料から成る反応容器内壁の堆積膜を水酸化ナトリウム溶液を使用した液体エッチングによる前処理及びガラス材の研磨材を用いた液体ホーニングによる後処理により除去することで密着性の良い表面性が維持でき球状突起を低減することが判明した。

(The number of spherical protrusions is a relative value when the comparative example with a nitrogen content of 5 atomic% is 10)
As a result, regardless of the nitrogen content, the deposited film on the inner wall of the reaction vessel made of alumina ceramic material is removed by pre-treatment by liquid etching using sodium hydroxide solution and post-treatment by liquid honing using glass abrasives. As a result, it was found that the surface property with good adhesion can be maintained and the spherical protrusions are reduced.

  In particular, it has been found that when the nitrogen content of the charge injection blocking layer also serving as an adhesion layer made of a silicon nitride film is in the range of 10 atomic% or more and 30 atomic% or less, the effect of reducing spherical protrusions is excellent, which is more preferable.

  The residual potential was the same in Example 1 and Comparative Example 1. However, the residual potential increases when the nitrogen content of the charge injection blocking layer that also serves as the adhesion layer made of the silicon nitride film exceeds 30%. Further, it was found that the range within 30% is a more preferable range.

  After the cylindrical aluminum cylinder 201 having a diameter of 80 mm and a length of 358 mm is installed in the reaction vessel 202 made of the alumina ceramic material of the vacuum processing apparatus 200 shown in FIG. 2, the production conditions shown in FIG. Six electrophotographic photoreceptors having a layer structure were prepared.

  Next, the reaction vessel 202 made of an alumina ceramic material was removed from the vacuum processing apparatus 200, and liquid etching and cleaning with pure water were sequentially performed with a 24% strength potassium hydroxide solution whose temperature was controlled at 80 ° C. to complete the pretreatment process.

Next, the residual film on the inner wall surface of the reaction vessel 202 made of the alumina ceramic material after the pretreatment process was removed by liquid honing, and the post-treatment process was completed by washing with pure water and drying. In addition, liquid honing used a spherical SUS material (BPS300 manufactured by Ito Kiko Co., Ltd.) having a center particle diameter of 35 μm as an abrasive. The ratio of water to abrasive was 5: 1, and the ejection pressure was 588.4 kPa (6 kgf / cm 2
).

  A deposition film forming process, a liquid etching process, a pure water cleaning process, a liquid honing process, a pure water cleaning process, and a drying process are repeated for the reaction vessel 202 made of the alumina ceramic material, and the electrophotographic photosensitive member is formed under the conditions shown in Table 3. Ten lots were produced, and the last one lot (six electrophotographic photosensitive members) was evaluated for spherical protrusions and residual potential in the same manner as in Example 1.

  Next, an electrophotographic photoreceptor for analysis in which only the charge injection blocking layer 104 serving also as an adhesion layer was deposited by the same method as in Example 1 was prepared, and the carbon content ratio C / (Si + O + C) was determined by ESCA measurement.

The results are shown in Table 4 together with Comparative Example 2. The evaluation of the spherical protrusion is CH4 of Comparative Example 2.
This is a relative comparison with the number of spherical protrusions of a lot produced at a flow rate of 50 ml / min (normal) as 100. Therefore, the smaller the numerical value, the fewer the spherical protrusions, and the better.

<Comparative example 2>
Using the apparatus shown in FIG. 2, a deposition film forming process, a liquid honing process, a pure water cleaning process, a drying process are performed on the reaction vessel 202 made of an alumina ceramic material under the same conditions as in Example 2 except that the liquid etching process is not performed. The process was repeated, 10 lots of electrophotographic photosensitive members were produced under the conditions shown in Table 3, and spherical projections and residual potential were evaluated in the same manner as in Example 1 for the last lot (six electrophotographic photosensitive members).

  The results are shown in Table 4 together with Example 2.

※ＣＨ４ ガスの流量は５０，１００，３００，５００，５５０［ｍｌ／ｍｉｎ（ｎｏｒｍａｌ）］の各流量パターンで作成。

* CH4 gas flow rate is created with each flow rate pattern of 50, 100, 300, 500, 550 [ml / min (normal)].

（球状突起数は炭素含有量が１５原子％の比較例を１００とした時の相対値）
以上の結果、何れの炭素含有量においてもアルミナセラミック材料から成る反応容器内壁の堆積膜を水酸化カリウム溶液により液体エッチングする前処理及びＳＵＳ材の研磨材を使用した液体ホーニングによる後処理によって除去することで密着性の良い表面性が維持でき球状突起を低減することが判明した。

(The number of spherical protrusions is a relative value when the carbon content is 15 atomic% and the comparative example is 100)
As a result, at any carbon content, the deposited film on the inner wall of the reaction vessel made of an alumina ceramic material is removed by pretreatment by liquid etching with a potassium hydroxide solution and by post-treatment by liquid honing using a SUS material abrasive. Thus, it was found that the surface property with good adhesion can be maintained and the spherical protrusions are reduced.

  In particular, it has been found that the effect of reducing spherical protrusions is excellent and more preferable when the carbon content of the charge injection blocking layer also serving as an adhesion layer made of a silicon carbide film is in the range of 20 atomic% to 40 atomic%.

  The residual potential was the same in Example 2 and Comparative Example 2, but the residual potential increased when the carbon content of the charge injection blocking layer, which also serves as the adhesion layer made of the silicon carbide film, exceeded 40 atomic%. Therefore, it was found that the range within 40% is a more preferable range.

  After the cylindrical aluminum cylinder 201 having a diameter of 80 mm and a length of 358 mm is installed in the reaction vessel 202 made of an alumina ceramic material of the vacuum processing apparatus 200 shown in FIG. 2, the production conditions shown in FIG. Six electrophotographic photoreceptors having a layer structure were prepared.

  Next, the reaction vessel 202 made of an alumina ceramic material was removed from the vacuum processing apparatus 200, and liquid etching and cleaning with pure water were sequentially performed with a 24% concentration sodium hydroxide solution whose temperature was controlled at 60 ° C. to complete the pretreatment process.

Next, the residual film on the inner wall surface of the reaction vessel 202 made of the alumina ceramic material after the pretreatment process was removed by liquid honing, and the post-treatment process was completed by washing with pure water and drying. Liquid honing is a spherical glass material (GB-AC manufactured by Toshiba Ballotini Co., Ltd.) with a center particle size of 200 μm, a spherical SUS material (BPS300 manufactured by Ito Kiko Co., Ltd.) with a center particle size of 130 μm. Polygonal SiC material (GC-10 manufactured by Fuji Seiki Seisakusho Co., Ltd.) and polygonal alumina material (FBR-10 manufactured by Fuji Seiki Seisakusho Co., Ltd.) with a center particle size of 130 μm. Four patterns were made using an abrasive. In all cases, the ratio of water and abrasive was 4: 1, and the ejection pressure was 588.4 kPa (6 gf / cm ² ).

  For each abrasive in the liquid honing process, a deposition film forming process, a liquid etching process, a pure water cleaning process, a liquid honing process, a pure water cleaning process, and a drying process are performed on the reaction vessel 202 made of the alumina ceramic material. Repeatedly, 10 lots of electrophotographic photoreceptors were prepared under the conditions shown in Table 5, and the spherical projections were evaluated in the same manner as in Example 1 for the last 1 lot (6 electrophotographic photoreceptors).

  Next, an analytical electrophotographic photosensitive member in which only the charge injection blocking layer 104 serving also as an adhesion layer is deposited by the same method as in Example 1 is prepared, and the nitrogen content ratio N / (Si + O + N) and the carbon content ratio C are determined by ESCA measurement. / (Si + O + C) was determined.

  The results are shown in Table 6 together with Comparative Example 3. The evaluation of the spherical protrusions is a relative comparison with the number of spherical protrusions of Comparative Example 3 being 100. Therefore, the smaller the numerical value, the fewer the spherical protrusions, and the better.

<Comparative Example 3>
The apparatus shown in FIG. 2 is used, and a honing process is not performed, and a deposition film forming process is performed on a reaction vessel 202 made of an alumina ceramic material.
The gas dry etching process, the pure water cleaning process, and the drying process were repeated to produce one lot of electrophotographic photosensitive members under the conditions shown in Table 5, and the last one lot (six electrophotographic photosensitive members) was the same as in Example 1. Spherical protrusions were obtained. Next, an analytical electrophotographic photosensitive member in which only the charge injection blocking layer 104 serving also as an adhesion layer is deposited by the same method as in Example 1 is prepared, and the nitrogen content ratio N / (Si + O + N) and the carbon content ratio C are determined by ESCA measurement. / (Si + O + C) was determined.

  The results are shown in Table 6 together with Example 3.

以上の結果、アルミナセラミック材料から成る反応容器内壁の堆積膜をアルカリ溶液により液体エッチングする前処理及び研磨材を使用した液体ホーニングによる後処理において使用する研磨材はガラス材、ＳＵＳ材、ＳｉＣ材、アルミナ材何れを用いて除去した場合でも密着性の良い表面性が維持でき、球状突起を低減することが判明した。

As a result of the above, the abrasive used in the pretreatment for liquid etching the deposited film on the inner wall of the reaction vessel made of an alumina ceramic material with an alkaline solution and the post treatment by liquid honing using an abrasive is glass material, SUS material, SiC material, It was found that the surface property with good adhesion can be maintained even when the alumina material is removed, and the spherical protrusions are reduced.

  However, the polishing material with higher hardness than the alumina ceramic material causes unevenness in the roughness of the surface of the alumina ceramic material by repeating liquid honing. Therefore, the polishing material used for liquid honing is lower than the hardness of the object to be liquid honed. Glass and SUS material are more effective and desirable from the viewpoint of durability.

FIG. 3 is a schematic cross-sectional view showing an example of a layer configuration of an electrophotographic photosensitive member that can be produced by the present invention. It is a typical block diagram which shows an example of the electrophotographic photoreceptor manufacturing apparatus applicable to this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Substrate 102 Photoconductive layer 103 Surface layer 104 Charge injection blocking layer also serving as an adhesion layer 105 Adhesion layer 200 Vacuum processing device 201 Cylindrical substrate 202 Reaction vessel 203 Gas introduction tube 204 High-frequency electrode 205 Matching box 206 Substrate support 207 Exhaust port 208 First high-frequency power source 209 Second high-frequency power source 210 Rotating shaft 211 Motor 212 Gear 213 Power branching portion 214 Shield 215 Cover 216 Bottom surface 217 Exhaust piping 218 Pressure adjustment valve

Claims (7)

A base is placed in a depressurizable reaction vessel at least partially made of a dielectric material, and the source gas supplied into the reaction vessel is decomposed by high-frequency power, and silicon atoms are used as a base on the substrate to form nitrogen atoms or carbon. In a deposited film forming method for forming a deposited film including a first layer formed of a non-single-crystal film containing atoms,
A method for forming a deposited film, comprising: removing the deposited film deposited on the dielectric material portion of the reaction vessel after the formation of the deposited film by a pre-processing step by liquid etching and a post-processing step by liquid honing.   The nitrogen atom content is 10 atomic% to 30 atomic% with respect to the constituent elements, and the carbon atom content is 20 atomic% to 40 atomic% with respect to the constituent elements. The deposited film forming method according to claim 1.   3. The deposited film forming method according to claim 1, wherein the dielectric material is made of alumina ceramic.   The deposited film forming method according to claim 1, wherein the liquid etching uses an alkaline solution.   The deposited film forming method according to claim 1, wherein the liquid honing uses an abrasive made of a material having a hardness lower than that of the dielectric material.   6. The method for forming a deposited film according to claim 1, wherein the removal of the deposited film is performed in the order of a liquid etching process, a water washing process, a liquid honing process, a water washing process, and a drying process.   The deposited film forming method according to claim 1, wherein a frequency of the high-frequency power is 50 MHz or more and 250 MHz or less.

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