JP2005163161A - Deposited film forming apparatus and deposited film forming method - Google Patents

Abstract

A deposition film forming apparatus and a deposition film forming method capable of uniformly plasma-treating a substrate to be processed and reducing image defects are provided.
A reaction vessel capable of being depressurized, at least a part of which is made of a dielectric member, a plurality of cylindrical substrates disposed on the same circumference, source gas introduction means, Having a plurality of high-frequency electrodes arranged outside, by applying a high-frequency power to the high-frequency electrode to generate a glow discharge in the reaction vessel, the raw material gas introduced into the reaction vessel is decomposed, In a deposition film forming apparatus and method for forming a deposition film on the plurality of cylindrical substrates; a cylindrical member having at least conductivity in the center of an arrangement circle where the cylindrical substrates are disposed is arranged in one of its axial directions. The distance between the ground material and the conductive material inside the reaction vessel facing the other ungrounded surface in the axial direction of the cylindrical member is 1 mm or more and 100 mm or less.
[Selection] Figure 1

Description

  The present invention relates to an apparatus and method for forming a deposited film on a substrate. In particular, the present invention relates to a deposited film forming apparatus and a deposited film forming method used for a functional film, particularly a semiconductor device, an electrophotographic photoreceptor, an image input line sensor, a photographing device, a photovoltaic device, and the like.

  Conventionally, as a deposition film forming method used for forming semiconductor devices, electrophotographic photoreceptors, image input line sensors, photographing devices, photovoltaic devices, other various electronic elements, optical elements, etc., plasma CVD, ion plating Many methods using plasma generated by high-frequency power, such as a plasma etching method and a plasma etching method, are known, and an apparatus therefor has been put into practical use.

  For example, a plasma CVD method, that is, a method of decomposing a source gas by high-frequency glow discharge and forming a thin film-like deposited film on a substrate has been put to practical use as a suitable deposited film forming means. In the following, it is used for the formation of a deposited film and the like, and various apparatuses have been proposed.

  In particular, plasma CVD (hereinafter abbreviated as “VHF-PCVD”) using high-frequency power in the VHF band is attracting attention, and the development of various deposited films using this VHF-PCVD method is active. It is being advanced. This is because the VHF-PCVD method has a relatively high deposition rate, and a high-quality deposited film can be obtained, so that it is expected that the cost of the product and the quality can be improved at the same time. is there. Development of a deposited film forming apparatus capable of simultaneously forming a plurality of a-Si electrophotographic photoreceptors and having high productivity is in progress.

For example, by arranging a part of the reaction vessel as a dielectric member and arranging a plurality of cathode electrodes on the outside of the reaction vessel, uniform high-frequency discharge can be easily achieved in a large area, and plasma treatment on a large area substrate can be performed uniformly and An apparatus that can be performed at high speed is disclosed. (For example, see Patent Document 1)
FIG. 2 shows a schematic configuration diagram as an example of such a deposited film forming apparatus.

2A is a schematic cross-sectional view, and FIG. 2B is a schematic cross-sectional view taken along a cutting line AA ′ in FIG. 2A. The reaction vessel 201 includes a dielectric member 201 (a), an upper lid 201 (b), and a bottom plate 201 (c). An exhaust pipe 209 is connected to the lower part of the reaction vessel 201, and the other end of the exhaust pipe 209 is connected to an exhaust device (not shown) (for example, a vacuum pump). A plurality of cylindrical substrates 205 on which deposited films are formed are arranged on the same circumference so as to be parallel to each other so as to surround the central portion of the reaction vessel 201. The plurality of cylindrical substrates 205 are each held by a substrate support 206 having a substrate heating heater 207 incorporated therein. In the reaction vessel 201, gas supply means 210 connected to a gas supply device (not shown) composed of gas cylinders such as SiH ₄ , GeH ₄ , H ₂ , CH ₄ , B ₂ H ₆ , PH ₃ , Ar, and He. A high frequency electrode 202 is installed outside the reaction vessel 201. A high frequency power source 203 is connected to the high frequency electrode 202 via a matching box 204 and a high frequency power branching means 212. Further, the cylindrical base body 205 can be rotated by each rotation mechanism 208.
JP 9-310181 A

  With such a conventional deposited film forming apparatus and method, it is possible to shorten the substrate processing time by increasing the film deposition rate, increase the number of simultaneously processable substrates, and improve the uniformity and reproducibility of the deposited film characteristics. It has become possible to obtain an electrophotographic photosensitive member having practical characteristics and uniformity that is inexpensive. In addition, if the inside of the vacuum reaction vessel is strictly cleaned, it is possible to obtain an electrophotographic photoreceptor with some defects.

  However, the level of market demand for products using these deposited films is increasing day by day, and in order to meet this demand, a deposited film forming apparatus and a deposited film forming method capable of producing higher quality products are required. .

  For example, in the case of an electrophotographic photoreceptor, there are very high demands for improving the process speed of the electrophotographic apparatus, downsizing the apparatus, reducing the price, and so on. It is indispensable to improve charging ability, sensitivity, etc., or to improve the yield rate during production. In recent years, digital electrophotographic devices and color electrophotographic devices, which have been remarkably popular, copy not only textual originals but also images such as photographs, pictures, design drawings, etc. There is a need to reduce so-called optical memory, in which an image previously copied to a photoreceptor remains in the next image. Also, this type of electrophotographic apparatus is required to form a film having a uniform film thickness and film quality on a substrate having a relatively large area in order to reduce density unevenness of an image.

  When the conventional deposited film forming apparatus and deposited film forming method are used, the uniformity of processing characteristics cannot be obtained in a wide range depending on the manufacturing conditions, and the uniformity level required in recent years can be obtained. Difficult to use as an electrophotographic photosensitive member.

  Further, in response to the recent high performance of electrophotographic apparatus, high image quality of the electrophotographic apparatus is required, and accordingly, the resolution of development is improved, and the number and size of image defects are reduced more than before. It is needed. In particular, in color copiers where demand is rapidly expanding, the demand for image defects is more severe than ever. However, in a product requiring a relatively thick deposited film with a large area, such as an electrophotographic photoreceptor, dust is easily generated during the production process because the production process of the photoreceptor takes a long time, and Since the area of the deposition surface is large, the probability of dust adhering tends to increase. Since the abnormal growth of the deposited film due to dust is directly connected to the image defect, it is necessary to eliminate it as much as possible.

  Therefore, in order to obtain a deposited film with a high yield in which the film deposition rate is high, the requirements of optical and electrical characteristics are satisfied, and the image formation by the electrophotographic process is small, there is a problem to be improved. Remains.

  The abnormal growth of the deposited film that occurs in the manufacturing process of the photosensitive member is as follows.

  The a-Si film has the property that, when dust of the order of several μm adheres to the substrate surface, abnormal growth, that is, so-called “spherical protrusions” grow with the dust as a nucleus during film formation. Spherical protrusions have a shape that is a reversal of the conical shape starting from dust, and there are many localized levels at the interface between the normal deposition part and the spherical protrusion part, so the resistance decreases, and the charged charge passes through the interface. Will come off to the substrate side. For this reason, the part with the spherical protrusion appears as a white point in the solid black image on the image (in the case of reversal development, it appears as a black point in the solid white image). The so-called “pochi” image defect has a stricter standard every year, and depending on the size, even if there are several A3 sheets, they may be treated as defective. Furthermore, the standard becomes more stringent when mounted on a color copying machine, and even if one is present on A3 paper, it may be defective.

  Since these spherical protrusions start from dust, the substrate to be used is precisely cleaned before film formation, and all the steps to be installed in the film formation apparatus are performed in a clean room or under vacuum. In this way, efforts have been made to reduce the amount of dust adhering to the substrate before the start of film formation, and the effect has been improved. However, the cause of the generation of the spherical protrusion is not only the dust adhering to the substrate. That is, when an a-Si photoconductor is manufactured, the required film thickness is very large, from several μm to several tens of μm, and therefore the film formation time ranges from several hours to several tens of hours. In addition to this, it also deposits on the reactor wall and the structures in the reactor. Since these furnace walls and structures do not have a controlled surface or temperature like the substrate, the adhesion is weak in some cases, and film peeling may occur during film formation over a long period of time. If even a slight peeling occurs during the film formation, it becomes dust and adheres to the surface of the photoreceptor being deposited, and this causes the abnormal growth of the spherical projections. Therefore, in order to maintain a high yield, careful management is required not only for management of the substrate before film formation but also for prevention of film peeling in the film formation furnace during film formation. The manufacture of the photoreceptor was difficult.

[Object of the invention]
An object of the present invention is to provide a deposited film forming apparatus and a deposited film forming method capable of uniformly plasma-treating a substrate to be processed and reducing abnormal growth of the deposited film.

  In order to achieve the above-described object, a deposited film forming apparatus according to the present invention includes a reaction vessel that is at least partially composed of a dielectric member and capable of being depressurized, and a plurality of reaction vessels disposed on the same circumference inside the reaction vessel. And a plurality of high-frequency electrodes arranged outside the reaction vessel, and high-frequency power is applied to the high-frequency electrodes to generate glow discharge in the reaction vessel. In the deposited film forming apparatus for decomposing the source gas introduced into the reaction vessel and forming a deposited film on the plurality of cylindrical substrates, at least approximately at the center in the arrangement circle where the cylindrical substrates are disposed. A conductive cylindrical member is disposed in a state where one of the cylindrical members in the axial direction is grounded, and the conductive material inside the reaction vessel is opposed to the other non-grounded surface in the cylindrical member axial direction. And the closest part Characterized in that the Oite 1mm or less than 100mm.

  The deposited film forming method according to the present invention is characterized in that a plasma treatment is performed on a cylindrical substrate using the deposited film forming apparatus described above.

  According to the present invention, a deposited film having good characteristics can be formed on a plurality of substrates uniformly with good reproducibility and at a high film deposition rate, and at the same time, image defects caused by spherical projections can be extremely reduced. It is.

  The embodiment of the present invention capable of obtaining the above effects will be described in detail below.

  In the deposited film forming apparatus in which a plurality of cylindrical substrates are arranged at equal intervals on the same circumference and the high-frequency power introducing means is arranged outside the reaction vessel, the adhesion of the deposited film is improved. When a method for reducing the generation of dust was examined, it was found that the configuration around the cylindrical substrate was asymmetric. Roughly speaking, this asymmetry can be considered by dividing it into the inside and the outside of the arrangement circle of the cylindrical substrate, and there is a possibility that the adhesion and stress of the film are different between the inside and the outside.

  Therefore, in order to confirm the influence of this asymmetry, the film was formed with the cylindrical substrate stationary, and the distribution of spherical projections in the circumferential direction of the cylindrical substrate was examined. As a result, it was found that the number of spherical protrusions was not evenly generated in the circumferential direction, but was frequently generated inside the arrangement circle of the cylindrical substrate. In other words, in order to improve the spherical protrusion in the deposited film forming apparatus of such a form and reduce the image defect to a level that can withstand use in a color copying machine, it is necessary to mainly reduce the inner spherical protrusion. Turned out to be.

  The reason why many spherical protrusions occur inside the arrangement circle of the cylindrical substrate is currently unknown, but when looking at the structure of the deposited film forming apparatus, the outer circumference of the circumference where the cylindrical substrates are arranged is the furnace of the deposited film forming apparatus. While the wall is facing, there is no furnace wall on the inside, and this difference in the shape of the space causes a difference in the film stress of the deposited film, affecting the adhesion. I imagine that would have given.

  On the other hand, when the distribution of the number of spherical protrusions in the circumferential direction of the cylindrical substrate was examined in the deposited film forming apparatus in which the cylindrical member according to the present invention was installed in the internal space of the plurality of cylindrical substrates, It has been found that the distribution of spherical protrusions is almost uniform in the circumferential direction. This is thought to be because the cylindrical member installed in the internal space of the plurality of cylindrical bases has a function corresponding to the furnace wall on the inner side, and the internal and external structures are symmetric while being simulated.

  When the cylindrical member is made of the same dielectric material as the furnace wall, the effect of reducing the most spherical protrusion is the greatest when the distance between the furnace wall and the cylindrical base is substantially equal to the distance between the cylindrical base and the cylindrical member. Appeared. However, as a side effect at this time, a deposited film also adheres to the cylindrical member, and thus a phenomenon has occurred in which the deposition rate of the film deposited on the cylindrical substrate is slightly reduced. Therefore, the present inventors further examined a configuration in which both the spherical protrusion improvement effect and the maintenance of the deposition rate are compatible.

  As a result, by changing the material of the cylindrical member from a dielectric material to a conductive material (for example, a metal material) and grounding, the diameter of the cylindrical member can be reduced while maintaining the spherical protrusion reduction effect. It turned out to be possible. On the other hand, it has been confirmed that the deposition rate is greatly improved by reducing the diameter of the cylindrical member, and if the size is below a certain level, the decrease in the deposition rate can be substantially improved to a negligible level. confirmed. That is, by changing the material of the cylindrical member to a conductive material (for example, a metal material) and grounding it, and making the diameter of the cylindrical member within a certain range, both the spherical protrusion improvement effect and the deposition rate maintenance are compatible. Turned out to be.

  In addition, when a high frequency electrode is provided outside the reaction vessel, the reaction vessel is formed with a portion facing the high frequency electrode, for example, a side wall made of a dielectric material, but other portions such as a top cover and a bottom plate are made of a conductive material. It is formed. This shields electromagnetic waves radiated from the high-frequency electrode to prevent high-frequency energy from entering from the top and bottom plates of the reaction vessel, and ensures the symmetry between the high-frequency electrode and the substrate to be processed. This is to promote the homogenization. In particular, in the configuration in which a plurality of high-frequency electrodes are provided outside the reaction vessel and the high-frequency power is branched and applied to the plurality of electrodes, the influence of the high frequency radiated from the branch member cannot be ignored. It is necessary to dispose a shielding member made of a conductive material, which is located between the cylindrical member and the cylindrical member and shields the high frequency. In the case where the cylindrical member is arranged in a state of being grounded to the upper lid or the bottom plate, the distance from the conductive material inside the reaction vessel facing the other surface that is not grounded in the axial direction of the cylindrical member (cylindrical member 1 mm or more in the configuration in which the cylindrical member is disposed in contact with the bottom plate, and the distance between the cylindrical member and the upper cover in the configuration in which the cylindrical member is disposed in contact with the upper lid. When the thickness is within a range of 100 mm or less, preferably 5 mm or more and 50 mm or less, more preferably 5 mm or more and 15 mm or less, the uniformity of plasma treatment and the long-term stability of plasma are improved, resulting in uneven film characteristics and image defects, It has been found that relatively small image defects are improved. At that time, the cylindrical member is formed such that the distance from the conductive material inside the reaction vessel facing the other surface that is not grounded in the axial direction of the cylindrical member gradually increases as the distance from the axial line of the cylindrical member increases in the radial direction. Then, it became clear by experiments of the present inventors that the effect becomes more remarkable.

  In other words, the uniformity of the plasma processing and the long-term stability of the plasma can be improved by adjusting the distance between the other non-grounded surface in the axial direction of the cylindrical member and the conductive material inside the reaction vessel. It is possible to easily and effectively suppress the unevenness of the characteristics of the deposited film and the improvement of the image defect. Therefore, according to the present invention, the uniformity and stability of the plasma are improved, and the deposited film formed on the cylindrical substrate is uniform in both the film thickness and film quality, and the deposited film having good film quality is reproducible. It can be formed well. Furthermore, regarding the temperature rise of each part by plasma, since the degree of the temperature rise is reduced and the temperature uniformity is improved, it is suppressed that the deposited film is peeled off from the members inside the reaction vessel and the reaction vessel, Defects are prevented from occurring in the deposited film formed on the cylindrical substrate. Therefore, by using the cylindrical substrate on which the deposited film is formed by the deposited film forming apparatus according to the present invention as the electrophotographic photoreceptor, it is possible to prevent defects in the obtained image.

  The reason why such an effect can be obtained is not completely clarified at present, but the present inventors consider as follows.

  If the distance from the conductive material inside the reaction vessel facing the other surface that is not grounded in the axial direction of the cylindrical member is relatively large, the power inside the reaction vessel cannot be sufficiently supplied, If the effect of installing the cylindrical member cannot be obtained and is brought close to the point of contact, depending on the manufacturing conditions, the electric capacity becomes too large, the plasma is biased, and abnormal discharge may occur in some cases.

  Therefore, the effect of the present invention is obtained by adjusting the distance from the conductive material inside the reaction vessel facing the other surface that is not grounded in the axial direction of the cylindrical member to have an appropriate electric capacity. I believe. Furthermore, the distance between the other surface of the cylindrical member that is not grounded in the axial direction of the cylindrical member and the conductive material inside the reaction vessel is formed so as to gradually increase as the distance from the axial line of the cylindrical member increases in the radial direction. Specifically, when the shape of the surface is formed in an elliptical shape or a spherical shape, the effect of the present invention can be obtained more, but this not only improves the adhesion of the deposited film, but also changes the capacitance. It is thought that this is because the effect of improving the uniformity and stability of the discharge is due to the gentle change.

  As described above, the deposited film forming apparatus and the deposited film forming method of the present invention are capable of forming a deposited film by plasma CVD capable of forming a highly uniform deposited film with high film thickness and quality in the in-plane direction of the cylindrical substrate. It is suitable for application as a device. In other words, plasma uniformity and long-term stability are improved, and a deposited film with excellent film thickness and film quality uniformity and good film quality is formed with good reproducibility, and the occurrence of image defects is greatly reduced. A deposition film forming apparatus and a deposition film forming method that drastically improve the yield, when forming a deposited film having a thickness of several tens of μm in a multi-layer structure like an a-Si electrophotographic photoreceptor. The present invention can be suitably applied to a forming apparatus and a forming method.

  According to the present invention, it is possible to provide a deposited film forming apparatus and a deposited film forming method capable of uniformly processing a substrate to be processed and reducing image defects.

  Hereinafter, a deposited film forming apparatus and a deposited film forming method of the present invention will be described in detail with reference to the drawings.

  FIG. 1 schematically shows an example of a highly productive apparatus capable of simultaneously forming a plurality of electrophotographic light-receiving members in the deposited film forming apparatus and method of the present invention.

  FIG. 1A is a schematic cross-sectional view, and FIG. 1B is a schematic cross-sectional view taken along the cutting line A-A ′ of FIG. The deposited film manufacturing apparatus shown in FIG. 1 limits the film formation space in which the source gas is decomposed to a cylindrical region by a reaction vessel 101 composed of a dielectric member 101 (a), an upper lid 101 (b) and a bottom plate 101 (c). The central axis of the cylindrical film-forming space passes through the center of the arrangement circle of the cylindrical substrate 105, and the high-frequency electrode 102 installed outside the arrangement circle of the cylindrical substrate 105 is disposed outside the dielectric member 101 (a). By being positioned in this position, the utilization efficiency of the source gas is improved, and at the same time, defects in the formed deposited film can be reduced.

An exhaust pipe 109 is connected to the lower part of the reaction vessel 101, and the other end of the exhaust pipe 109 is connected to an exhaust device (not shown) (for example, a vacuum pump). A plurality of cylindrical substrates 105 on which a deposited film is formed are arranged on the same circumference so as to be parallel to each other so as to surround the central portion of the reaction vessel 101. The plurality of cylindrical substrates 105 are respectively held by a substrate support 106 in which a substrate heating heater 107 is incorporated. In the reaction vessel 101, there is a cylindrical member 111 made of a conductive material at the approximate center, a gas cylinder made of SiH ₄ , GeH ₄ , H ₂ , CH ₄ , B ₂ H ₆ , PH ₃ , Ar, He or the like. There is a gas supply means 110 connected to the illustrated gas supply apparatus, and a high-frequency electrode 102 is installed outside the reaction vessel 101. A high frequency power source 103 is connected to the high frequency electrode 102 via a matching box 104 and a high frequency power branching means 112. Further, the cylindrical base body 105 can be rotated by each rotating mechanism 108.

  Here, the cylindrical member 111, the upper lid 101 (b) of the reaction vessel 101, and the bottom plate 101 (c) are made of a conductive material, and the cylindrical member 111 is disposed on the bottom plate 101 (c) in a grounded state. Yes. Any conductive material can be used, but aluminum, iron, stainless steel, gold, silver, copper, nickel, chromium, titanium, and other metal materials are easy to process and highly durable. This is also preferable. In addition, composite materials composed of two or more of these materials are also preferably used.

  In the deposited film forming apparatus 101 of the present invention, the cylindrical member 111 needs to be electrically grounded. By grounding, it is presumed that the high-frequency electrode 102 is acting as a pseudo counter electrode. In addition, the distance between the cylindrical member 111 and the inner surface of the upper lid 101 (b) is in the range of 1 mm to 100 mm, preferably 5 mm to 50 mm, more preferably 5 mm to 15 mm, and the electric capacity is made appropriate. Thus, the uniformity of the plasma processing and the long-term stability of the plasma are improved, so that the characteristics unevenness of the deposited film and image defects, particularly relatively small image defects, are improved, and the effects of the present invention can be obtained. At that time, the distance between the cylindrical member 111 and the other non-grounded surface in the axial direction of the conductive material inside the reaction vessel gradually increases as the distance from the axial line of the cylindrical member increases in the radial direction. When formed, the effect becomes more prominent. Specifically, the effect of the present invention can be obtained more when the shape of the surface is an elliptical surface or a spherical surface.

  FIG. 4 is a schematic diagram for explaining the positional relationship between the upper lid 401 (b) and the cylindrical member 411 and the shape of the other surface that is not grounded in the axial direction of the cylindrical member 411. 4A shows a plane in which the distance d between the upper lid 401 (b) and the cylindrical member 411 is constant, and FIGS. 4B and 4C show the distance between the upper lid 401 (b) and the cylindrical member 411. FIG. d1 and d2 are gradually increased as they are separated from the axis of the cylindrical member 411 in the radial direction, and the shape of each surface is formed into an elliptical shape and a spherical shape. As shown in FIGS. 4B and 4C, the distance between the other non-grounded surface in the axial direction of the cylindrical member 411 and the conductive material inside the reaction vessel is the axis of the cylindrical member. When the distance gradually increases as the distance from the surface increases in the radial direction, the distance of 1 mm to 100 mm defined in the present invention refers to d1 which is the shortest distance.

  3 shows an example of a similar apparatus configuration except that the cylindrical member 311 is arranged on the upper lid 301 (b) in FIG. 1, and FIG. 5 shows the bottom plate 501 (c) and the cylindrical shape. The schematic diagram for demonstrating the positional relationship with the member 511 and the shape of the other surface which is not earth | grounded of the cylindrical member 511 axial direction is shown. The explanation is the same as in FIG. 1 and FIG.

  As described above, the cylindrical members 111 and 311 are sufficiently grounded to define the distance between the other surface of the cylindrical member that is not grounded in the axial direction of the cylindrical member and the conductive material inside the reaction vessel. In order to obtain the effect, for example, a separate high frequency power source is prepared for the cylindrical members 111 and 311, or an output is output from the single high frequency power source 103 and 303 to the high frequency electrodes 102 and 302 and the cylindrical members 111 and 311. Since there is no cost or labor for branching and aligning, the cost of the deposited film forming apparatus itself can be reduced, which leads to a reduction in the manufacturing cost of the electrophotographic photoreceptor.

  In the present invention, the effect of reducing image defects is particularly high when the frequency of the high frequency power is in the range of 50 to 450 MHz. This seems to be due to the rapid increase in pressure at which plasma can be stably generated in a frequency region lower than 50 MHz. According to the study by the present inventors, for example, when the frequency is 13.56 MHz, it is confirmed that the pressure at which plasma can be stably generated is about one to half digits higher than that when the frequency is 50 MHz or more. ing. At such a high pressure, particles such as polysilane are easily generated in the film formation space, and when these particles are taken into the deposited film, spherical protrusions are easily generated. In the present invention, by setting the frequency of the high-frequency power to 50 MHz or more, the plasma generation pressure can be sufficiently lowered, so that the probability of generation of particles is drastically reduced and a good deposited film is formed over the entire circumference of the cylindrical substrate. It is considered a thing.

  Further, in a frequency region higher than 450 MHz, the uniformity of the film characteristics is different from the case of 450 MHz or less due to a decrease in plasma uniformity. If there is a difference in the uniformity of such film characteristics, there will also be a difference in the stress of the film at the same time, and film peeling is likely to occur near the boundary. For this reason, image defects are likely to deteriorate. In the frequency region where the frequency is higher than 450 MHz, the power absorption near the power introduction means is large, and electrons are most frequently generated here, so that plasma non-uniformity is likely to occur and the characteristics of the deposited film are uneven. Easy to connect. At frequencies of 450 MHz or less, extreme power absorption in the vicinity of the power introduction means is unlikely to occur, resulting in high plasma uniformity and even film property uniformity.

  As the high frequency power sources 103 and 303, any high frequency power source can be suitably used as long as it can generate high frequency power suitable for the apparatus. Further, the output fluctuation rate of the high frequency power sources 103 and 303 is not particularly limited.

  The matching boxes 104 and 304 used in the present invention can be suitably used in any configuration as long as the load can be matched with the high-frequency power sources 103 and 303. In addition, as a method of taking the alignment, an automatically adjusted method is preferable in order to avoid complexity at the time of manufacturing, but even if manually adjusted, there is no influence on the effect of the present invention. . In addition, as for the position where the matching boxes 104 and 304 are arranged, there is no problem wherever the matching boxes 104 and 304 are installed within the matching range, but the wiring inductance from the matching boxes 104 and 304 to the high-frequency power introducing means 102 and 302 can be obtained. It is desirable to make the arrangement as small as possible because it is possible to achieve matching under a wide load condition.

  Copper, aluminum, gold, silver, platinum, lead, nickel, cobalt, iron, chromium, molybdenum, titanium, stainless steel, etc. as the material of the high frequency electrodes 102, 302 and the high frequency power branching means 112, 312 have good heat conduction, Since conduction is good, it is preferable. A composite material composed of two or more of these materials is also preferably used.

  The number of the high-frequency electrodes 102 and 302 is more preferably the same as the cylindrical bases 105 and 305 or 1/2 of the cylindrical bases 105 and 305. When the cylindrical bases 105 and 305 are halved, it is optimal to arrange them so that the distances between the two adjacent cylindrical bases 105 and 305 are equal. The supply of power to the plurality of high-frequency electrodes 102 and 302 is performed by, for example, branching the power supply path by the high-frequency power branching means 112 and 312 from one high-frequency power source 103 and 303 through the matching boxes 104 and 304. be able to. Further, for example, the power supply path from one high-frequency power source 103 or 303 may be branched by the high-frequency power branching means 112 or 312, and then power may be supplied through a plurality of matching boxes. A separate high-frequency power source and a matching box may be provided for each of the electrodes 102 and 302, but the frequency of the high-frequency power introduced from all the high-frequency electrodes 102 and 302 is completely the same, the cost of the device, the device From the viewpoint of size, it is preferable that power is supplied to all the high-frequency electrodes 102 and 302 from one high-frequency power source.

  As the high-frequency electrodes 102 and 302, rod-like, cylindrical, spherical, plate-like cathode electrodes, means for providing an opening in the outer conductor of the coaxial structure, and supplying power from there can be used.

  The material of the dielectric members 101 (a) and 301 (a) of the reaction vessels 101 and 301 used in the present invention is preferably a ceramic material, specifically, alumina, zirconia, mullite, cordierite, silicon carbide. It is preferable to be made of a material containing at least one of boron nitride, aluminum nitride, silicon nitride, and the like because the adhesion of the deposited film is high and effective for preventing the formation of spherical protrusions. Among these, alumina, boron nitride, and aluminum nitride are more preferable because they have excellent electrical characteristics such as dielectric loss tangent and insulation resistance, and have low absorption of high-frequency power.

  Further, when producing an electrophotographic photoreceptor from the ease of processing, the shape of the dielectric member 101 (a), 301 (a) is preferably cylindrical, but if necessary, elliptical, polygonal shape The shape may be selected depending on the member to be manufactured.

  The material of the top lid 101 (b), 301 (b), bottom plate 101 (c), bottom plate 301 (c) of the reaction vessel 101, 301 is copper, aluminum, gold, silver, platinum, lead, nickel, cobalt, iron, It is preferable to use a material such as chromium, molybdenum, titanium, or stainless steel because it is conductive and has good heat conduction. A composite material composed of two or more of these materials is also preferably used.

  The cylindrical bases 105 and 305 may be any material having a material corresponding to the purpose of use. Of the materials, copper, aluminum, gold, silver, platinum, lead, nickel, cobalt, iron, chromium, molybdenum, titanium, and stainless steel are preferable because of their good electrical conductivity. Furthermore, a composite material composed of two or more of these materials is also desirable for improving heat resistance.

  Substrate heating heaters 107 and 307 may be any heating element that is vacuum specification, specifically, sheathed heaters, plate heaters, ceramic heaters, carbon heaters and other electrical resistance heating elements, halogen lamps, infrared lamps, etc. Examples include a heat-radiating lamp heating element, a heating element that uses liquid, gas, or the like as a heating medium, and heat exchange means. As the surface material of the substrate heating heaters 107 and 307, metals such as stainless steel, nickel, aluminum and copper, ceramics, heat-resistant polymer resins and the like can be used.

  Formation of a deposited film using the deposited film forming apparatus of FIG. 1 is performed, for example, as follows.

  First, the cylindrical substrate 105 held on the substrate support 106 is installed in the reaction vessel 101, and the inside of the reaction vessel 101 is exhausted through an exhaust pipe 109 by an exhaust device (not shown). Subsequently, the cylindrical substrate 105 is heated and controlled to a predetermined temperature by the substrate heating heater 107.

  When the cylindrical substrate 105 reaches a predetermined temperature, the source gas is introduced into the reaction vessel 101 via the gas supply means 110. After confirming that the flow rate of the source gas is the set flow rate and that the pressure in the reaction vessel 101 is stable, predetermined high frequency power is supplied from the high frequency power source 103 to the high frequency electrode 102 via the matching box 104. Glow discharge occurs in the reaction vessel 101 by the supplied high frequency power, and the source gas is excited and dissociated to form a deposited film on the cylindrical substrate 105.

  After the formation of the desired film thickness, the supply of the high frequency power is stopped, and then the supply of the source gas is stopped to finish the formation of the deposited film. When forming a multi-layered deposited film, the same operation is repeated a plurality of times. In this case, in each layer, as described above, once the formation of one layer is completed, the discharge is once stopped completely, and after the setting is changed to the gas flow rate and pressure of the next layer, the discharge occurs again. The next layer may be formed, or a plurality of layers may be continuously formed by gradually changing the gas flow rate, pressure, and high-frequency power to the set values of the next layer within a certain period of time after the formation of one layer. It may be formed. Further, when different gas species are used between the layers, it is preferable to sufficiently evacuate the residual gas in the reaction vessel 101 once between the layers because there is no fear of contamination of different gas species.

  During the formation of the deposited film, the cylindrical substrate 105 may be rotated at a predetermined speed by the rotation mechanism 108 as necessary.

  The formation of the deposited film using the deposited film forming apparatus of FIG. 3 is performed in the same manner as in FIG.

  By using the present invention, an a-Si electrophotographic light-receiving member as shown in FIG. 6, for example, can be formed.

  An electrophotographic photosensitive member 600 shown in FIG. 6A is provided with a photoconductive layer 602 having a photoconductivity having a-Si containing a hydrogen atom or a halogen atom as a constituent element on a support 601. Yes.

  An electrophotographic photoreceptor 600 shown in FIG. 6B has a photoconductive layer 602 made of a-Si containing a hydrogen atom or a halogen atom as a constituent element on a support 601 and a photoconductive layer 602. A Si-based (or amorphous carbon-based) surface layer 603 is provided.

  An electrophotographic photoreceptor 600 shown in FIG. 6 (c) is composed of an a-Si based charge injection blocking layer 604 on a support 601 and a-Si containing hydrogen atoms or halogen atoms as constituent elements. A photoconductive layer 602 having a property and an a-Si (or amorphous carbon) surface layer 603 are provided.

  An electrophotographic photoreceptor 600 shown in FIG. 6D is provided with a photoconductive layer 602 on a support 601. This photoconductive layer 602 includes a charge generation layer 605 made of a-Si containing a hydrogen atom or a halogen atom as a constituent element, and a charge transport layer 606, on which an a-Si-based (or amorphous carbon-based) surface layer 603 is formed. Is provided.

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

(Example 1)
Using the deposited film forming apparatus shown in FIG. 1, on the cylindrical substrate 105 made of aluminum having a diameter of 80 mm and a length of 358 mm, the oscillation frequency of the high-frequency power source 103 is set to 105 MHz, and in accordance with the conditions shown in Table 1, the cylindrical substrate side is sequentially installed. An a-Si electrophotographic photoreceptor comprising a charge injection blocking layer, a photoconductive layer, and a surface layer was produced. At this time, the material of the cylindrical member 111 and the upper lid 101 (b) is made of stainless steel, the surface of the cylindrical member 111 facing the upper lid 101 (b) is a flat surface, and the distance between the cylindrical member 111 and the upper lid 101 (b) In the range of 1 mm to 100 mm.

(Comparative Example 1)
An a-Si electrophotographic photoreceptor was produced in the same manner as in Example 1 except that the distance between the cylindrical member 111 and the upper lid 101 (b) was changed to 0.2 mm and 130 mm in Example 1.

  The a-Si electrophotographic photoreceptors produced in Example 1 and Comparative Example 1 were subjected to the following methods for the number of spherical protrusions, image defects, charging ability, sensitivity, optical memory, uneven charging ability, uneven sensitivity, and uneven optical memory. Was evaluated.

(Number of spherical protrusions)
The surface of the obtained photoreceptor was observed with an inverted metal microscope (Versonmet-2, Union Optics). Then, the number of spherical protrusions having a size of 10 μm or more and less than 20 μm and a size of 20 μm or more was counted and the number per 10 cm ² was examined.

(Image defect)
The photoconductor for electrophotography produced in this example was installed in a Canon copier iR5000 modified for this test, the process speed was 265 mm / sec, the pre-exposure (LED with a wavelength of 660 nm) light quantity of 4 lx · s, the main charger An image was formed under the condition of a current value of 1000 μA, and an A3 size black original was copied. The images thus obtained were observed, and the number of white spots caused by spherical protrusions having a diameter of 0.1 mm to less than 0.3 mm and a diameter of 0.3 mm or more was counted.

(Charging ability, uneven charging ability)
A constant current (for example, 1000 μA) was passed through the main charger of the electrophotographic apparatus, and the dark portion potential was measured with a potential sensor of a surface potentiometer (TREK Model 344) set at the position of the developer. Therefore, the larger the dark part potential, the better the charging ability. The charging ability was measured over the entire area in the axial direction of the photosensitive member, and the average value was taken. Then, the charging ability unevenness was evaluated by a value obtained by dividing the difference between the maximum value and the minimum value by the average value.

(Sensitivity, sensitivity unevenness)
After adjusting the main charger current so that the dark part potential at the developing unit position becomes a constant value (for example, 450 V), a predetermined white paper having a reflection density of 0.1 or less is used for the original, and the bright part potential at the developing unit position is predetermined. Evaluation is based on the amount of image exposure when adjusting the image exposure (semiconductor laser with a wavelength of 655 nm) so as to be a value. Therefore, the smaller the image exposure amount, the better the sensitivity. Sensitivity measurement was performed over the entire region in the axial direction of the photoreceptor, and the average value was taken. Therefore, the smaller the value, the better. The sensitivity unevenness was evaluated by a value obtained by dividing the difference between the maximum value and the minimum value by the average value.

(Optical memory, uneven optical memory)
After adjusting the current value of the main charger so that the dark portion potential at the developing unit position becomes a predetermined value, the image exposure light amount is adjusted so that the bright portion potential when the predetermined white paper is used as a document has a predetermined value. . When a Canon ghost test chart (part number: FY9-9040) with a black circle with a reflection density of 1.1 and a diameter of 5 mm is placed on the platen and a Canon halftone chart is placed on top of it In this copy image, the difference between the reflection density of the black circle with a diameter of 5 mm and the reflection density of the halftone portion of the ghost chart recognized on the halftone copy was measured. The optical memory was measured over the entire area in the axial direction of the photoreceptor, and the average value was taken. Therefore, the smaller the value, the better. Optical memory unevenness was evaluated by dividing the difference between the maximum and minimum values by the average value.

Evaluation of the number of spherical protrusions, image defects, charging ability, sensitivity, optical memory, charging ability unevenness, sensitivity unevenness, and optical memory unevenness in Comparative Example 1 was performed by setting the distance between the cylindrical member 111 and the upper lid 101 (b) to 130 mm. The following procedure was performed based on the produced electrophotographic photoreceptor.

◎: Improvement of 20% or more ◎ to ○: Improvement of 10% or more and less than 20% ○: Improvement of less than 10% △: Equivalent ×: Deterioration

  The evaluation results of Example 1 and Comparative Example 1 are shown in Table 2. As can be seen from Table 2, the electrophotographic photoreceptor produced in Example 1 with the distance between the cylindrical member 111 and the upper lid 101 (b) being 1 mm or more and 100 mm or less shows better results than Comparative Example 1. Thus, it can be seen that the effect of improving is increased when the distance between the cylindrical member 111 and the upper lid 101 (b) is 5 mm or more and 50 mm or less.

  In addition, it was found that the electrophotographic photoreceptor produced in Example 1 has a uniform and good image with no unevenness in the halftone image in image characteristics. Furthermore, when a text document was copied, a clear image with high black density was obtained. In copying a photographic original, a clear image faithful to the original can be obtained, which is extremely good.

  Further, in the apparatus configuration in which the cylindrical member 311 is arranged on the upper lid 301 (b) as shown in FIG. 3, the distance between the cylindrical member 311 and the bottom plate 301 (c) is similarly examined. As a result, similarly, the electrophotographic photosensitive member manufactured by setting the distance between the cylindrical member 311 and the bottom plate 301 (c) to 1 mm or more and 100 mm or less gives good results, and the cylindrical member 311 and the bottom plate 301 (c) are obtained. It has been found that the effect is improved when the distance is 5 mm or more and 50 mm or less, and the effect is further improved when the distance is 5 mm or more and 15 mm or less.

(Example 2)
In Example 1, the shape of the surface facing the upper lid 101 (b) was changed to flat, elliptical, and spherical as shown in FIGS. 4 (a), 4 (b), and 4 (c). In the same manner as in Example 1, an a-Si electrophotographic photoreceptor was produced. At that time, the distance between the cylindrical member 111 and the upper lid 101 (b) was 20 mm when the surface shape was flat, and the shortest distance was 20 mm when the surface shape was elliptical or spherical.

  The electrophotographic photoreceptor produced in Example 2 was evaluated with reference to the electrophotographic photoreceptor produced in Comparative Example 1 with the distance between the cylindrical member 111 and the upper lid 101 (b) being 130 mm as in Example 1. The results are shown in Table 3. As is apparent from Table 3, it is effective to make the distance between the cylindrical member 111 and the upper lid 101 (b) gradually longer as the distance from the axis of the cylindrical member 111 increases in the radial direction. It becomes clear that becomes more prominent.

  In addition, it was found that the electrophotographic photosensitive member produced in Example 2 was uniform in the image characteristics and uniform and good images were obtained. Furthermore, when a text document was copied, a clear image with high black density was obtained. In copying a photographic original, a clear image faithful to the original can be obtained, which is extremely good.

  Further, in the apparatus configuration in which the cylindrical member 311 is arranged in a grounded state on the upper lid 301 (b) as shown in FIG. It has been found that the effect becomes more prominent when the distance between the cylindrical member 311 and the bottom plate 301 (c) is gradually increased as the distance increases.

Example 3
In Example 1, the distance between the cylindrical member 111 and the upper lid 101 (b) is 10 mm, and the oscillation frequency of the high frequency power source 103 is changed in the range of 30 MHz to 500 MHz. A photographic photoreceptor was prepared.

  The electrophotographic photoreceptor produced in Example 3 was evaluated with reference to the electrophotographic photoreceptor produced in Comparative Example 1 with the distance between the cylindrical member 111 and the upper lid 101 (b) being 130 mm as in Example 1. Table 4 shows the results. As is apparent from Table 4, it can be seen that the effect of the present invention can be obtained by setting the oscillation frequency of the high-frequency power within the range of 50 MHz to 450 MHz.

  In addition, it was found that the electrophotographic photosensitive member produced in Example 3 has a uniform and good image with no unevenness in the halftone image in image characteristics. Furthermore, when a text document was copied, a clear image with high black density was obtained. In copying a photographic original, a clear image faithful to the original can be obtained, which is extremely good.

  Further, in the apparatus configuration in which the cylindrical member 311 is arranged on the upper lid 301 (b) as shown in FIG. 3, the same examination was performed, and similarly, the range was set to 50 MHz to 450 MHz. It was found that the effects of the present invention can be obtained.

Example 4
3. Using the deposited film forming apparatus shown in FIG. 3, on a cylindrical substrate 305 made of aluminum having a diameter of 80 mm and a length of 358 mm, in addition to a high frequency power source 303 having an oscillation frequency of 105 MHz, a high frequency power source (not shown) having an oscillation frequency of 60 MHz An a-Si electrophotographic photoreceptor comprising a charge injection blocking layer, a photoconductive layer (first layer region, second layer region), and a surface layer in order from the cylindrical substrate side according to the conditions shown in Table 5 Produced. At this time, the material of the cylindrical member 311 and the bottom plate 301 (c) is made of aluminum, the surface of the cylindrical member 311 facing the bottom plate 301 (c) is a flat surface, and the distance between the cylindrical member 311 and the bottom plate 301 (c) Was 10 mm.

  The electrophotographic photoreceptor produced in Example 4 was evaluated with reference to the electrophotographic photoreceptor produced in Comparative Example 1 with the distance between the cylindrical member 111 and the upper lid 101 (b) being 130 mm, as in Example 1. As a result, as in Example 1, good results were obtained.

  In addition, it was found that the electrophotographic photosensitive member produced in Example 4 has a uniform and good image with no unevenness in the halftone image in image characteristics. Furthermore, when a text document was copied, a clear image with high black density was obtained. In copying a photographic original, a clear image faithful to the original can be obtained, which is extremely good.

Further, in the apparatus configuration in which the cylindrical member 111 is arranged on the bottom plate 101 (c) as shown in FIG. 1, when the same examination is performed, the same good results as in Example 4 are obtained. It was.

It is the typical block diagram which showed an example of the deposited film formation apparatus of this invention. It is the typical block diagram which showed an example of the manufacturing apparatus of the conventional light-receiving member for electrophotography. It is the typical block diagram which showed another example of the deposited film formation apparatus of this invention. It is the elements on larger scale of the deposited film forming apparatus which concerns on this invention, Comprising: Typical position for demonstrating the positional relationship of an upper cover and a cylindrical member, and the shape of the other surface which is not earth | grounded of a cylindrical member axial direction It is a block diagram. It is the elements on larger scale of the deposited film forming apparatus which concerns on this invention, Comprising: Typical position for demonstrating the positional relationship of a baseplate and a cylindrical member, and the shape of the other surface which is not earth | grounded in the cylindrical member axial direction It is a block diagram. It is the figure which showed an example of the layer structure of the light-receiving member for electrophotography which can be formed by this invention.

Explanation of symbols

101, 201, 301: Reaction vessel
101 (a), 201 (a), 301 (a): Dielectric member
101 (b), 201 (b), 301 (b), 401 (b): Upper lid
101 (c), 201 (c), 301 (c), 501 (c): Bottom plate
102, 202, 302: High frequency electrode
103, 203, 303: High frequency power supply
104, 204, 304: Matching box
105, 205, 305: Cylindrical substrate
106, 206, 306: substrate support
107, 207, 307: Substrate heating heater
108, 208, 308: Rotation mechanism
109, 209, 309: Exhaust piping
110, 210, 310: Gas supply means
111, 311, 411, 511: Cylindrical members
112, 212, 312: High-frequency power branching means
600: Photoconductor for electrophotography
601: Support
602: Photoconductive layer
603: Surface layer
604: Charge injection blocking layer
605: Charge generation layer
606: Charge transport layer

Claims (9)

  A reaction vessel capable of being depressurized, at least a part of which is made of a dielectric member, a plurality of cylindrical substrates disposed on the same circumference inside the reaction vessel, a raw material gas introduction means, and an outside of the reaction vessel A plurality of high-frequency electrodes arranged, and applying a high-frequency power to the high-frequency electrodes to generate glow discharge in the reaction vessel, thereby decomposing the raw material gas introduced into the reaction vessel, In the deposited film forming apparatus for forming a deposited film on the cylindrical substrate, at least one of the cylindrical members having conductivity in the center of the arrangement circle in which the cylindrical substrate is disposed is arranged in the axial direction of the cylindrical member. It is arranged in a grounded state, and the distance from the conductive material inside the reaction vessel facing the other surface that is not grounded in the axial direction of the cylindrical member is 1 mm or more and 100 mm or less in the closest part Deposition film shape Apparatus.   The distance between the cylindrical member in the axial direction of the cylindrical member and the conductive material inside the reaction vessel facing the other surface that is not grounded is 5 mm or more and 50 mm or less at the closest portion. Deposited film forming device.   The distance between the cylindrical member in the axial direction of the cylindrical member and the conductive material inside the reaction vessel facing the other surface that is not grounded is 5 mm or more and 15 mm or less at the closest portion. Deposited film forming device.   Formed so that the distance from the conductive material inside the reaction vessel facing the other non-grounded surface in the axial direction of the cylindrical member gradually increases as the distance from the axial line of the cylindrical member increases in the radial direction 4. The deposited film forming apparatus according to claim 1, wherein the deposited film forming apparatus is formed.   The deposited film forming apparatus according to claim 4, wherein the shape of the other surface that is not grounded in the axial direction of the cylindrical member is an elliptical surface.   The deposited film forming apparatus according to claim 4, wherein the shape of the other surface not grounded in the axial direction of the cylindrical member is a spherical surface.   7. The deposited film forming apparatus according to claim 1, wherein an oscillation frequency of the high frequency power applied to the high frequency electrode is in a range of 50 to 450 MHz.   2. The deposited film formed on the plurality of cylindrical substrates is made of a-Si mainly composed of Si atoms, and the plurality of cylindrical substrates are used as an electrophotographic photoreceptor. 8. The deposited film forming apparatus according to any one of items 7 to 7.   A deposited film forming method for forming a deposited film on the plurality of cylindrical substrates using the deposited film forming apparatus according to claim 1.

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