JP5058511B2 - Deposited film forming equipment - Google Patents

Description

  The present invention relates to a deposited film forming apparatus for forming a deposited film on a substrate by a glow discharge plasma CVD (Chemical Vapor Deposition) method, and more particularly to an apparatus for manufacturing an electrophotographic photosensitive member.

  2. Description of the Related Art Conventionally, techniques for manufacturing element members used for electrophotographic photoreceptors from various materials such as selenium, cadmium sulfide, zinc oxide, phthalocyanine, amorphous silicon (hereinafter referred to as “a-Si”) have been proposed. Non-single crystalline deposited films containing silicon (silicon) atoms represented by a-Si as a main component, for example, amorphous deposited films such as a-Si compensated with hydrogen and / or halogen (for example, fluorine, chlorine, etc.) High performance, high durability and pollution-free photoconductor. Some of such non-single crystalline deposited films have been put into practical use. As a method for forming a deposited film, there are a number of conventional methods such as sputtering, thermal CVD for decomposing source gas by heat, photo-CVD for decomposing source gas by light, and plasma CVD for decomposing source gas by plasma. It has been known. Among them, the plasma CVD method is currently in practical use as a method for forming an a-Si deposited film for electrophotography, and various apparatuses for the plasma CVD method have been proposed. Specifically, the raw material gas is decomposed by glow discharge such as direct current or high frequency (RF, VHF) or microwave, and is formed into a thin film on a conductive substrate such as glass, quartz, heat resistant synthetic resin film, stainless steel, and aluminum. The deposited film is formed. For example, photoconductivity in which a surface protective layer composed of a non-photoconductive amorphous material is provided on a photoconductive layer composed mainly of silicon atoms and composed of an amorphous material containing at least one of a hydrogen atom and a halogen atom. Members are known. This surface protective layer is made of a non-photoconductive amorphous material containing hydrogen atoms based on silicon atoms and carbon atoms.

  A method of forming a deposited film such as a-Si by such a conventional technique is performed as follows, for example.

  FIG. 5 is a diagram schematically showing an example of a deposited film forming apparatus for RF plasma CVD using a 13.56 MHz high-frequency power source used for producing an electrophotographic photosensitive member (Patent Document). 1). This deposited film forming apparatus includes a reaction vessel 600 and an exhaust device (not shown) for depressurizing the inside of the reaction vessel 600. In the reaction vessel 600, a grounded conductive receiving shaft 605, a substrate heater 608, and a gas introduction pipe 606 are provided, and a cylindrical substrate 607 is attached to the conductive receiving shaft 605. Further, a cylindrical discharge electrode 601 made of a conductive material is disposed. The discharge electrode 601 forms the reaction vessel 600 together with the base plate 602 and the upper lid 603, and the base plate 602 and the upper lid 603 are insulated from the discharge electrode 601 by the insulator 604. A high frequency power supply 609 of 13.56 MHz is connected to the discharge electrode 601 through a matching box 610.

  A gas supply device (not shown) is connected to a gas introduction pipe 606 in the reaction vessel 600 via a gas introduction valve 619. Further, the exhaust device (not shown) is connected to the reaction vessel 600 via the main valve 615, and a vacuum gauge 611 is provided in the middle of the connection path.

  Hereinafter, an example of a method for producing an electrophotographic photoreceptor using the deposited film forming apparatus of FIG. 5 will be described.

  First, for example, a cylindrical substrate 607 obtained by performing mirror processing on the surface of an aluminum cylinder using a lathe is attached to the conductive receiving shaft 605 so as to surround the substrate heater 608 in the reaction vessel 600.

Next, the main valve 615 is opened, and the reaction vessel 600 and the gas introduction pipe 606 are exhausted by an exhaust device (not shown). When the vacuum gauge 611 detects that the pressure is 0.67 Pa or less, the gas introduction valve 619 is opened, and an inert gas for heating (for example, argon) is introduced into the reaction vessel 600 from the gas introduction pipe 606. Then, the flow rate of the inert gas for heating and the opening of the main valve 615 or the exhaust speed of the exhaust device are adjusted so that the inside of the reaction vessel 600 has a desired pressure. Thereafter, a temperature controller (not shown) is operated, the cylindrical substrate 607 is heated by the substrate heater 608, and the temperature of the cylindrical substrate 607 is controlled to a desired temperature of 20 ° C to 500 ° C. When the cylindrical substrate 607 is heated to a desired temperature, the introduction of the inert gas is gradually stopped. At the same time, a source gas for film formation, for example, a material gas such as SiH ₄ , Si ₂ H ₆ , CH ₄ , or C ₂ H ₆ is doped with B ₂ H ₆ , PH _3, or the like by a gas supply device (not shown). After being mixed with gas, it is gradually introduced into the reaction vessel 600. Next, it adjusts so that each raw material gas may become predetermined | prescribed flow volume with a mass flow controller not shown. At that time, the opening of the main valve 615 or the exhaust speed of the exhaust device (not shown) is monitored while monitoring the vacuum gauge 611 so that the inside of the reaction vessel 600 is maintained at a desired pressure of 0.1 Pa to several hundred Pa. adjust.

  After completing the film formation preparation by the above procedure, the formation of the deposited film on the cylindrical substrate 607 is started. First, after confirming that the pressure in the reaction vessel 600 has stabilized, the high frequency power source 609 is set to a desired power, and the high frequency power is supplied to the discharge electrode 601 to cause a high frequency glow discharge. At this time, the matching box 610 is adjusted so that the reflected wave is minimized so that the value obtained by subtracting the reflected power from the high frequency incident power becomes a desired value. By the discharge energy of the high-frequency glow discharge, each source gas introduced into the reaction vessel 600 is decomposed and adhered onto the surface of the cylindrical substrate 607 to form a predetermined deposited film. During film formation, the cylindrical base 607 may be rotated at a predetermined speed by a driving device (not shown).

  After the deposition film having a desired thickness is formed, the supply of high-frequency power is stopped, the flow of each source gas into the reaction vessel 600 is stopped, the inside of the reaction vessel 600 is once evacuated, and the film forming process is completed. By repeatedly performing such a film forming process, an electrophotographic photosensitive member is formed.

With this technology, an electrophotographic photoreceptor having improved electrical characteristics, optical characteristics, and photoconductivity characteristics can be produced, and image quality can be improved by forming an image using this electrophotographic photoreceptor. Is possible.
Japanese Patent Laid-Open No. 10-63024

  With the above-described conventional deposited film forming apparatus, it has become possible to obtain a photoreceptor having practical characteristics and uniformity to some extent. In particular, among the film forming methods by the plasma CVD method, the RF plasma CVD method using the RF band as the high frequency power can easily obtain a film having good characteristics, and therefore, the production of an electrophotographic photosensitive member using a-Si, etc. Widely used in

  However, in recent years, the specs of electrophotographic apparatuses required in the market have become stricter year by year, and competition for price and running cost has intensified as well as higher image quality, higher speed, higher durability, and higher functionality. . Accordingly, an electrophotographic photosensitive member using a-Si not only contributes to the improvement of the electrical characteristics and the image quality as in the conventional case, but also requires an inexpensive member with lower cost. It has become.

  However, an electrophotographic photosensitive member using a-Si must have a thick film in order to obtain sufficient charging ability because of the high dielectric constant of a-Si. A deposited film having a thickness of 100 μm must be formed. Therefore, in the manufacturing method using the RF plasma CVD method, it takes a long time to form a film and the production cost tends to increase.

  Further, the conventional plasma CVD apparatus is often a coaxial deposited film forming apparatus as shown in FIG. In this case, the environment around the cylindrical substrate 607 is symmetric, and a uniform film thickness and film quality can be obtained. On the other hand, only one electrophotographic photosensitive member is manufactured per film forming furnace (deposited film forming apparatus). The production efficiency was inevitably low.

  On the other hand, improvement of the deposition rate has been conventionally studied as one attempt to increase the production amount per film forming furnace. However, when the deposition rate is increased, the film quality of the deposited film inevitably deteriorates and the characteristics as an electrophotographic photosensitive member tend to deteriorate. That is, there is a case where the production efficiency and the characteristics as an electrophotographic photosensitive member are in a trade-off relationship, and a sufficiently satisfactory result cannot be obtained.

  An object of the present invention is to solve the above-described conventional problems and to provide a deposited film forming apparatus which can be manufactured stably with a high yield without lowering the electrical characteristics and reducing the manufacturing cost.

The present invention comprises an exhaust part and a gas introduction part, and a plurality of cylindrical substrates can be arranged therein, and can constitute a vacuum-tight reaction vessel and a side wall of the reaction vessel, and a plurality of cylindrical substrates are arranged and a discharge electrode provided so as to surround the position to be, in the deposited film forming apparatus for forming a deposited film on a surface of a plurality of cylindrical substrates, the deposited film forming apparatus, each of the plurality of cylindrical substrates And a partition plate provided between the positions where the plurality of cylindrical substrates are arranged and electrically connected to the discharge electrodes, so that the surfaces of each other are not directly opposed to each other , partition plate, characterized in that it comprises a cylindrical portion outlet constituting a part of the exhaust portion is provided, and a plate portion that is joined to the cylindrical portion about the cylindrical portion.

  The deposited film forming apparatus of the present invention is provided with a partition plate electrically connected to the discharge electrode between the cylindrical substrates so that the deposited film forming surfaces of the cylindrical substrates do not directly face each other. Since the partition plate constitutes a part of the exhaust part, a good deposited film can be formed. As a result, it is possible to produce an electrophotographic photosensitive member having good characteristics at low cost and with high productivity.

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

  First, how the present invention was conceived will be described. The inventors of the present invention have considered using a deposited film forming apparatus capable of manufacturing a large number of electrophotographic photosensitive members in a single film forming process in order to reduce the manufacturing cost and efficiently manufacture the electrophotographic photosensitive member. That is, instead of the conventional coaxial-type deposited film forming apparatus as shown in FIG. 5, a deposited film forming apparatus capable of arranging a plurality of cylindrical substrates 607 in a single reaction vessel 600 as shown in FIG. Was used. 6A is a schematic longitudinal sectional view of the deposited film forming apparatus, and FIG. 6B is a schematic transverse sectional view taken along a cutting line XX of FIG. 6A. In addition, the same code | symbol is provided about the part similar to the deposited film formation apparatus shown in FIG. 5, and description is abbreviate | omitted.

  In the deposited film forming apparatus shown in FIG. 6, the plurality of cylindrical substrates 607 are attached to a rotating shaft 508 that is a conductive receiving shaft with a built-in substrate heater and grounded, so that they are equidistant on the same circumference. Be placed. The rotating shaft 508 can be rotated by a driving mechanism (not shown). Discharge electrodes 601 are installed so as to surround these cylindrical base bodies 607. The reaction vessel 600 is connected to an exhaust device (not shown) via an exhaust pipe 505. In the vicinity of the discharge electrode 601, a raw material gas introduction tube (a raw material gas introduction portion) 606 is arranged at equal intervals in the circumferential direction.

  According to this deposited film forming apparatus, the number of photoconductors manufactured per apparatus greatly increases, and as a result, a significant cost reduction can be expected.

  However, when an experiment is actually performed, the electrical characteristics of the obtained electrophotographic photosensitive member are all the same as that shown in FIG. 5 (one electrophotographic photosensitive member in one film forming process). Compared to a device that can only be manufactured), it was not good. That is, the deposited film forming apparatus shown in FIG. 6 can obtain the same characteristics as the electrophotographic photosensitive member manufactured in the single-rolling furnace only in a prescription range narrower than the coaxial single-rolling furnace shown in FIG. The productivity was not always good because the selectable range of prescription was narrow.

  In order to investigate this cause, in the deposited film forming apparatus shown in FIG. 6, the prescription was not sufficient as compared with the coaxial single-piece furnace in a state where the cylindrical substrate 607 was kept stationary without being rotated. Film formation was performed, and unevenness in the circumferential characteristics was examined. As a result, the portion of the deposited film on the side surface of the cylindrical substrate 607 facing the side wall (discharge electrode 601) of the reaction vessel 600 (portion A in FIG. 6B), that is, the portion facing the discharge electrode 601 in the vicinity. The characteristics were as good as or better than those of a coaxial single furnace. However, in other parts, it was found that the characteristics were inferior compared with the case of the coaxial type single furnace. In particular, the characteristics of the deposited film at the portions where the side surfaces of the cylindrical substrate 607 are close to each other (the B portion and the C portion in FIG. 6B) are considerably inferior to those of the coaxial single-piece furnace. Turned out to be.

  The present inventors considered this cause as follows. In the case of the deposited film forming apparatus shown in FIG. 6, high-frequency power is applied to the discharge electrode 601, and the counter electrode of the discharge electrode 601 functions as a plurality of grounded cylinders arranged inside. This is a substrate 607. That is, in the circumferential direction of the cylindrical substrate 607, a sufficient high-frequency electric field acts on a portion (A portion) that is close to and opposed to the discharge electrode 601 and a deposited film having a good film quality is formed. However, high-frequency power from the discharge electrode 601 is not sufficiently applied to a portion where the side surfaces of the cylindrical substrate 607 are close to each other (B portion and C portion), that is, a region where the ground surfaces face each other. Become. Therefore, it is assumed that the decomposition and excitation of the source gas are insufficient and the film characteristics of the deposited film are deteriorated.

  As a method for solving this problem, the present inventors thought that a partition plate may be provided at a position where the side surfaces of the cylindrical base 607 are close to each other so as to be blinded. Therefore, a deposited film forming apparatus shown in FIG. 7 was produced. FIG. 7A is a schematic longitudinal sectional view of the deposited film forming apparatus, and FIG. 7B is a schematic transverse sectional view taken along a cutting line XX in FIG. 7A. The same parts as those in the deposited film forming apparatus shown in FIGS.

  This deposited film forming apparatus has a configuration in which a partition plate 411 is provided in a reaction vessel 600. Specifically, in the reaction container 600 of the deposited film forming apparatus shown in FIG. 7, one cylindrical substrate 607 is disposed in each area partitioned by the partition plate 411. Each cylindrical base 607 is respectively held by a rotating shaft 508 that incorporates a base heating heater and is grounded. An exhaust pipe 405 provided at the center of the reaction vessel 600 is connected to an exhaust device (not shown) and can exhaust the reaction vessel 600. The partition plate 411 is in contact with the discharge electrode 601 so as to be electrically connected.

  In this deposited film forming apparatus, the cylindrical substrates 607 do not face each other directly by the partition plate 411. Since the partition plate 411 is in electrical contact with the discharge electrode 601, the partition plate 411 is a portion facing the partition plate 411 (in the apparatus shown in FIG. 6, the cylindrical substrates 607 are directly facing each other). A high frequency electric field can be effectively applied to the B portion and the C portion). That is, when looking around the cylindrical substrate 607, high-frequency power is applied uniformly, and there is no ground plane. As a result, it has been found that the same characteristics as those of the coaxial deposited film forming apparatus (single-removal furnace) shown in FIG. 5 can be obtained over the entire circumference of the cylindrical substrate 607.

  Thus, by using the partition plate 411, the characteristics in the circumferential direction of the cylindrical base 607 were almost uniform over the entire circumference. However, the variation in the axial characteristics of the cylindrical base 607 has become somewhat large. This is considered to be due to the fact that the distance between the cylindrical base 607 and the discharge electrode is substantially reduced by the function of the partition plate 411 as the discharge electrode. It is considered that when the distance between the discharge electrode and the cylindrical substrate 607 becomes short, the influence of the gas flow tends to affect the unevenness of the deposited film.

  As another problem, it was found that the use of the partition plate 411 increases the amount of by-product called polysilane in the reaction vessel 600. When the production of the electrophotographic photoreceptor is repeated, it is necessary to remove the polysilane in the reaction vessel 600 before the production process is finished and the next production process is started. For example, if the next production is performed in a state where an unnecessary material such as polysilane remains in the reaction vessel 600, the possibility that the unnecessary material adheres to the cylindrical substrate 607 increases before the deposited film is formed. Such deposits cause defects in the deposited film and cause image defects in the electrophotographic photosensitive member.

  Further, when the amount of polysilane in the reaction vessel 600 after the production of the electrophotographic photosensitive member is increased, the time for treating (removing) the polysilane is inevitably increased, resulting in an increase in cost.

  Furthermore, when a large amount of polysilane is generated, it may adversely affect the deposited film forming process. For example, the possibility that polysilane peels off from the wall in the reaction vessel 600 during the formation of the deposited film and adheres to the cylindrical substrate 607 is increased, causing a deposited film defect and causing an image defect of the electrophotographic photosensitive member. turn into.

  The inventors of the present invention closely observed the inside of the reaction vessel 600 after the manufacturing process of the photoreceptor, and polysilane was found in the vicinity of the end portion of the partition plate 411 and the joining portion (D portion and E portion shown in FIG. 7B, etc.). ) Was found to have accumulated a lot. The reason why particularly a large amount of polysilane is generated in this portion is presumed as follows.

  The source gas introduced from the gas introduction pipe 606 shows a flow as indicated by an arrow in FIG. Then, it is considered that the gas collides with the partition plate 411 at the D portion and the E portion, and the gas flow is temporarily interrupted, and as a result, polysilane is likely to be generated at the D portion and the E portion.

  In order to solve these problems, the present inventors have further studied. As a result, as shown in FIGS. 1, 2, and 4, the gas flow in the axial direction is made uniform by providing the exhaust port 113 in the partition plate 111 and installing the exhaust unit at the approximate center of the reaction vessel 100. As a result, it was found that the unevenness of the characteristic in the axial direction is improved. Furthermore, since the gas was exhausted from the E portion of FIG. 7B where a large amount of polysilane was generated, it was found that the generation of polysilane in the vicinity of the E portion was very small. Further, as shown in FIGS. 1 and 2, a gas introduction hole 112 is provided in the partition plate 111 to provide a function as a gas introduction portion. In particular, it has been found that by disposing the gas introduction hole 112 in the vicinity of the discharge electrode 101, the amount of polysilane generated in the D portion of FIG. 7B where the gas flow collides with the partition plate 111 is suppressed.

  An example of the deposited film forming apparatus of the present invention produced based on the above examination and consideration is shown in FIG. This deposited film forming apparatus is a highly productive apparatus capable of simultaneously forming a plurality of electrophotographic photoreceptors. FIG. 1 (a) is a schematic longitudinal sectional view, and FIG. 1 (b) is FIG. 1 (a). It is a schematic cross-sectional view in alignment with the cutting line XX.

  An outline of the configuration of the deposited film forming apparatus will be described first. The deposited film forming apparatus includes a reaction vessel 100 that can be vacuum-tight and a cylindrical discharge electrode 101. The reaction vessel 100 includes an exhaust part and a gas introduction part, and a plurality of cylindrical substrates 107 can be arranged inside. The discharge electrode 101 is provided so as to surround a position where the plurality of cylindrical base bodies 107 are arranged. By applying a high frequency power to the discharge electrode 101 to generate glow discharge in the reaction vessel 100, the raw material gas introduced into the reaction vessel 100 is decomposed to form a deposited film on the plurality of cylindrical substrates 107. Can be formed. The cylindrical base body 107 is grounded via the rotating shaft 108. Further, the deposited film forming surfaces of the cylindrical substrate 107 are not directly opposed to each other, and are not opposed to the grounded portion. An electrically connected partition plate 111 is provided. The partition plate 11 serves as an exhaust part and a gas introduction part. That is, the exhaust port 113 constituting a part of the exhaust part is disposed in the vicinity of the center position of the cylindrical discharge electrode 101 of the partition plate 111, and the gas introduction hole 112 constituting a part of the gas introduction part is The partition plate 111 is positioned in the vicinity of the discharge electrode 101. The exhaust part is located on the center line of the cylindrical discharge electrode 101.

  In this configuration, the discharge electrode 101 also serves as a reaction furnace wall, and forms the reaction vessel 100 together with the base plate 102 and the upper lid 103. The base plate 102 and the upper lid 103 are insulated from the discharge electrode 101 by the insulator 104.

  In the reaction vessel 100, one cylindrical substrate 107 is arranged in each area partitioned by the partition plate 111. Each cylindrical base body 107 is held by a rotating shaft 108 with a built-in heater for heating the base. The rotating shaft 108 can be rotated by a driving device (not shown).

  The exhaust pipe 105 is connected to an exhaust device (not shown) and can exhaust the reaction vessel 100, and is connected to an exhaust part in the base plate 102. The exhaust port 113 of the partition plate 111 constitutes a part of this exhaust part. Further, the partition plate 111 is provided with a gas introduction hole 112 constituting a part of the gas introduction portion. The source gas can be introduced into the reaction vessel 100 by this gas introduction part. A high frequency power source 109 is connected to the discharge electrode 101 via a matching box 110, and high frequency power can be supplied into the reaction vessel 100.

  FIG. 2 is a schematic diagram illustrating an example of the partition plate 111 of the present embodiment. As shown in FIG. 2, the partition plate 111 has a configuration in which four plate portions 111a are joined to a cylindrical portion 111b located at the center thereof. The cylindrical portion 111 b is provided with an exhaust port 113 and constitutes a part of the exhaust portion, and is connected to the exhaust pipe 105 via the connection pipe 114. The plate portion 111 a is hollow, is connected to a gas introduction device (not shown), and functions as a gas introduction portion that introduces gas into the reaction vessel 100 through the gas introduction hole 112. The plate portion 111a is electrically connected to the discharge electrode 101, and a high frequency is applied. The material of the partition plate 111 may be anything as long as it is a conductive material. As described above, the partition plate 111 of the present embodiment not only functions as a partition plate in which the side surfaces of the cylindrical base body 107 are not directly opposed to each other, but also functions as an exhaust part having the exhaust port 113, and the gas introduction hole 112 is provided. It also functions as a raw material gas introduction section. An exhaust port 113 is provided at a position far from the discharge electrode 101 of the partition plate 111, and a gas introduction hole 112 is provided at a position near the discharge electrode 101.

  Furthermore, in this embodiment, the connection pipe 114 that connects the exhaust part of the partition plate 111 and the exhaust pipe 105 connected to the base plate 102 is made of an insulator. The partition plate 111 functions as a discharge electrode that causes glow discharge around the substantially cylindrical substrate 107. Therefore, the partition plate 111 and the cylindrical base body 107 installed on the base plate 102 are electrically insulated.

  In the present embodiment, the discharge electrode 101, the partition plate 111, the base plate 102, and the upper lid 103 shown in FIG. 1 are made of a conductive material. Any conductive material can be used, but metal materials such as aluminum, iron, stainless steel, gold, silver, copper, nickel, chromium and titanium are easy to process and highly durable. This is also preferable. Moreover, the composite material which consists of 2 or more types in these materials is also used suitably.

The high frequency power used in this embodiment may be in any frequency band, but good electrophotographic characteristics are easily obtained in the 1 to 20 MHz RF band, typically 13.56 MHz. This is presumed to be related to the fact that SiH _{3, which} is easy to obtain a good film quality as a decomposition species, can be stably obtained, and the uniformity and stability of plasma. The high frequency power supply 109 can be suitably used as long as it can generate high frequency power suitable for the deposited film forming apparatus. There is no particular limitation on the output fluctuation rate of the high-frequency power source 109.

  The matching box 110 used in this embodiment can be suitably used with any configuration as long as it can match the load with the high-frequency power source 109. As a method for obtaining the alignment, an automatically adjusted method is preferable in order to avoid complexity at the time of manufacturing, but even the manually adjusted method has no influence on the effect of the present invention. Further, there is no problem even if the matching box 110 is arranged anywhere within the range where matching can be obtained. However, an arrangement in which the inductance of the wiring from the matching box 110 to the discharge electrode 101 is as small as possible is preferable because matching can be achieved under a wide load condition.

  The cylindrical base 107 used in this embodiment may be any material having a material corresponding to the purpose of use. The material of the cylindrical substrate 107 is a metal such as copper, aluminum, gold, silver, platinum, lead, nickel, cobalt, iron, chromium, molybdenum, titanium, and alloys thereof such as stainless steel. Is preferable because it is good. Furthermore, a composite material composed of two or more of these materials is also preferable because heat resistance is improved.

  Next, an outline of a method for producing an electrophotographic photoreceptor using the deposited film forming apparatus shown in FIG. 1 will be described.

  First, the cylindrical substrate 107 is installed in each area separated by the partition plate 111 in the reaction vessel 100, and after the reaction vessel 100 is evacuated, the cylindrical substrate 107 is replaced with an internal heating heater (not shown). To a predetermined temperature. The cylindrical substrate 107 is preferably maintained at 150 ° C. to 350 ° C. during the manufacture of the electrophotographic photosensitive member.

  Next, a source gas (for example, silane) is introduced into the reaction vessel 100 through the source gas introduction hole 112, and the high frequency power from the high frequency power source 109 is adjusted by the matching box 110 and applied to the discharge electrode 101. At this time, high frequency power is also applied to the partition plate 111. By applying this high frequency power, glow discharge is generated, the source gas is decomposed, and a deposited film is formed on the surface of the cylindrical substrate 107. The cylindrical substrate 107 is rotated by a rotating shaft 108 connected to a drive mechanism (not shown), whereby a uniform deposited film is formed in the circumferential direction. After the deposition film having a desired thickness is formed, the application of the high-frequency power is stopped and the inflow of gas from the gas introduction unit into the reaction vessel 100 is stopped to finish the formation of the deposition film.

  In order to obtain a desired deposited film characteristic, when a deposited film composed of a plurality of layers is formed on the surface of the cylindrical substrate 107, the above operation is repeated.

  By using the deposited film forming apparatus of the present invention, for example, an a-Si based electrophotographic light-receiving member as shown in FIG. 3 can be formed.

  FIG. 3 is a view showing a general layer structure of an electrophotographic photoreceptor 700 manufactured according to the present invention. This electrophotographic photoreceptor 700 is formed on an amorphous silicon-based lower blocking layer 702, a photoconductive layer 703 made of a-Si: (H, X), and an amorphous silicon-based (or amorphous) on a cylindrical substrate 107. A carbon-based surface layer 704 is provided.

  Although not described in detail, in this embodiment, a gas introduction valve 619, a main valve 615, and a vacuum gauge 610 similar to those of the conventional apparatus shown in FIG. 5 are provided, and these may be used in the same manner as the conventional method described above. Good.

  Examples of the present invention and effects thereof will be specifically described below. In addition, this invention is not limited to a following example.

Example 1
In this embodiment, the deposited film forming apparatus of the present invention using the plasma CVD method shown in FIG. 4 is used. In addition, the same code | symbol is provided about the structure similar to the deposited film formation apparatus shown in FIG. 1, and description is abbreviate | omitted.

  Four cylindrical aluminum cylinders having an outer diameter of 30 mm and a length of 358 mm were prepared as the cylindrical substrate 107 and attached to the rotating shaft 108 in the reaction vessel 100. Then, while rotating the cylindrical substrate 107 at 5 rpm, the lower blocking layer 702, the photoconductive layer 703, and the surface layer 704 are laminated on the cylindrical substrate 107 under the conditions shown in Table 1, and electrophotographic photosensitive Four bodies 700 were formed. The high-frequency power source 109 of this embodiment is an RF power source that applies high-frequency power with a frequency of 13.56 MHz to the discharge electrode 101.

  In addition, since the partition plate 211 of the present embodiment does not serve as a gas introduction part and is not provided with the gas introduction hole 112, the reaction vessel 100 is separately provided in the vicinity of the rotating shaft 108 and the cylindrical substrate 107. A gas introduction pipe 206 is provided.

(Comparative Example 1)
In this comparative example, the deposited film forming apparatus using the plasma CVD method shown in FIG. 6 was used.

  As the cylindrical substrate 607, four cylindrical aluminum cylinders having an outer diameter of 30 mm and a length of 358 mm were prepared and attached to the rotating shaft 508 in the reaction vessel 600. Then, under the conditions shown in Table 1 while rotating the cylindrical substrate 607 at 5 rpm, the lower blocking layer 702, the photoconductive layer 703, and the surface layer 704 are laminated on the cylindrical substrate 607 to form an electrophotographic photosensitive film. Four bodies 700 were formed. The high frequency power supply 609 of this comparative example is an RF power supply that applies high frequency power with a frequency of 13.56 MHz to the discharge electrode 601. The deposited film forming apparatus of this comparative example is not provided with a partition plate.

(Example 2)
In this embodiment, the deposited film forming apparatus of the present invention using the plasma CVD method shown in FIG. 1 was used.

  Four cylindrical aluminum cylinders having an outer diameter of 30 mm and a length of 358 mm were prepared as the cylindrical substrate 107 and attached to the rotating shaft 108 in the reaction vessel 100. Then, while rotating the cylindrical substrate 107 at 5 rpm, the lower blocking layer 702, the photoconductive layer 703, and the surface layer 704 are laminated on the cylindrical substrate 107 under the conditions shown in Table 1, and electrophotographic photosensitive Four bodies 700 were formed. The high-frequency power source 109 of this embodiment is an RF power source that applies high-frequency power with a frequency of 13.56 MHz to the discharge electrode 101.

  Unlike the first embodiment, the partition plate 111 according to the present embodiment also serves as a gas introduction portion, and is provided with a gas introduction hole 112.

(Comparative Example 2)
In this comparative example, the deposited film forming apparatus using the plasma CVD method shown in FIG. 7 was used.

  As the cylindrical substrate 607, four cylindrical aluminum cylinders having an outer diameter of 30 mm and a length of 358 mm were prepared and attached to the rotating shaft 508 in the reaction vessel 600. Then, under the conditions shown in Table 1 while rotating the cylindrical substrate 607 at 5 rpm, the lower blocking layer 702, the photoconductive layer 703, and the surface layer 704 are laminated on the cylindrical substrate 607 to form an electrophotographic photosensitive film. Four bodies 700 were formed. The high frequency power supply 609 of this comparative example is an RF power supply that applies high frequency power with a frequency of 13.56 MHz to the discharge electrode 601.

  Since the partition plate 411 of this comparative example does not serve as a gas introduction part and is not provided with a gas introduction hole, a gas introduction is separately provided in the reaction vessel 600 in the vicinity of the rotating shaft 508 and the cylindrical substrate 607. A tube 606 is provided. Moreover, the partition plate 411 of this comparative example does not also serve as an exhaust part and is not provided with an exhaust port.

(Evaluation method)
Next, an evaluation method of the electrophotographic photoreceptor 700 produced according to each example of the present invention and each comparative example will be described.

(Chargeability)
The manufactured electrophotographic photoreceptor 700 was set in an electrophotographic apparatus, a constant current (for example, 700 μA) was passed through the main charger, and the dark portion potential was measured by a potential sensor of a surface electrometer set at the position of the developer. Therefore, the larger the dark portion potential, the better the charging ability. Here, as an electrophotographic apparatus, a copy machine GP55 (trade name) manufactured by Canon Inc. was used for experiments, and Model 344 (trade name) manufactured by Trek Incorporated of the United States was used as a surface electrometer. . The charging ability was measured at the central portion of the electrophotographic photoreceptor 700 in the bus line direction.

The four electrophotographic photoreceptors 700 manufactured at the same time were each subjected to the above-described measurement, and the charging ability was evaluated using the average value. The charging performance evaluation results were ranked as follows based on the results of Comparative Example 1.
◎… 20% or more improvement ○ ~ ◎ ... 15% or more less than 20% improvement ○ ... 10% or more less than 15% improvement △ ~ ○ ... 5% or more less than 10% improvement △ ... Equivalent x… Deteriorated (Axial unevenness of charging ability)
The above-described measurement of the charging ability is performed while changing the position in 2 cm increments in the direction of the generatrix of the electrophotographic photosensitive member 700, and the difference between the maximum value and the minimum value of the charging ability is divided by the average value. The axial nonuniformity of the charging ability was calculated.

Each of the four electrophotographic photoreceptors 700 manufactured at the same time was subjected to the above-described measurement, and the average value thereof was used to evaluate the axial unevenness of the charging ability. The evaluation results of the axial unevenness were ranked as follows according to the ratio (percentage) with respect to the result of Comparative Example 1 as a reference (100%). The smaller the ratio to Comparative Example 1 (100%), the better the result. In Example 2 and Comparative Example 2, the measurement of the unevenness of the charging ability in the axial direction is not performed.
◎ ... Less than 30% ○ ~ ◎ ... 30% or more and less than 50% ○ ... 50% or more and less than 70% Δ ~ ○ ... 70% or more and less than 90% Δ ... Equivalent to comparative example (90% or more and less than 110%)
×… worsening (110% or more)
(sensitivity)
In the above-described electrophotographic apparatus, after adjusting the current to the main charger so that the dark portion potential at the position of the developing device becomes a constant value (450 V in the present invention), a predetermined blank sheet having a reflection density of 0.1 or less as a document The sensitivity was determined using. Specifically, the sensitivity was evaluated based on the image exposure amount when adjusting the image exposure with a semiconductor laser having a wavelength of 655 nm so that the light portion potential at the developing unit position was a predetermined value (50 V in the present invention). Therefore, the smaller the image exposure amount, the better the sensitivity. Sensitivity measurement was performed at the center of the electrophotographic photoreceptor 700 in the direction of the generatrix.

The four electrophotographic photoreceptors 700 manufactured at the same time were measured as described above, and the sensitivity was evaluated using the average value. The sensitivity evaluation results were ranked as follows based on the results of Comparative Example 1.
◎ ... Improvement of 40% or more ○ ~ ◎ ... Improvement of 30% or more and less than 40% ○ ... Improvement of 20% or more and less than 30% △ ~ ○ ... Improvement of 10% or more but less than 20% △ ... Equivalent ×… worsening (image defect)
The produced electrophotographic photosensitive member 700 was installed in the same copying machine used for measuring the charging ability (a copying machine GP55 (trade name) manufactured by Canon Inc. modified for experiment). Then, the number of white spots (white spots) having a diameter of 0.2 mm or more in the same area of the copy image obtained by copying with the entire black chart placed on the document table was counted.

The four electrophotographic photoreceptors 700 manufactured at the same time were measured as described above, and the number of image defects was evaluated using the average value. The image defect evaluation results were expressed as white point reduction rates based on the results of Comparative Example 2, and were ranked as follows. In Comparative Example 1, image defects are not measured.
◎… Reduction of 50% or more ○ ~ ◎… Reduction of 40% or more and less than 50% ○… Reduction of 30% or more and less than 40% Δ ~ ○… Reduction of 20% or more but less than 30% Δ… Equivalent to Comparative Example (20% Less than)
×… Increase (comparison of evaluation results of each example and each comparative example)
Table 2 shows the evaluation results of each example and each comparative example.

  As can be seen from Table 2, with respect to charging ability and sensitivity, Comparative Example 2 having the partition plate 411 gave better results than Comparative Example 1, but the partition plate 111, 211 was provided with an exhaust port 112. According to the first and second embodiments, it is further improved over the second comparative example. Further, it was found that the improvement in the axial direction unevenness of the charging ability was observed in Example 1 as compared with Comparative Example 1. Further, with respect to image defects (white spots), a better result was obtained in Example 1 than in Comparative Example 2, but a better result was obtained in Example 2 than in Example 1.

  Summing up these results, the best result was obtained in Example 2. In Example 1, although the number of image defects was larger than that in Example 2, a generally good result was obtained. Comparative Example 2 was inferior to Example 1 in all of the charging ability, sensitivity, and image defects, and Comparative Example 1 was inferior overall as compared with Comparative Example.

(Dry etching)
In the deposited film forming apparatuses of Examples 1 and 2 and Comparative Example 2 described above, after producing the electrophotographic photoreceptor 700, dry etching was performed to remove the polysilane in the reaction vessels 100 and 600.

  The dry etching procedure is as follows. Although not shown, after the electrophotographic photosensitive member 700 is manufactured, a dummy cylinder (anode electrode) for dry etching is installed in place of the cylindrical substrates 107 and 607 and the reaction vessels 100 and 600 are evacuated. After sufficiently evacuating the reaction vessels 100 and 600, an etching gas is introduced into the reaction vessels 100 and 600 and adjusted to a predetermined pressure, and then high frequency power is applied to the discharge electrodes 101 and 601 to generate plasma. To do. Then, dry etching of the respective reaction vessels 100 and 600 was performed under the conditions shown in Table 3.

Each time 1 hour passed after dry etching, the amount of polysilane in the reaction vessels 100 and 600 was measured. Depending on the amount of polysilane in the reaction vessels 100 and 600, the treatment rate of polysilane was evaluated as follows. The results are shown in Table 4.
◎… No polysilane remains.
○… Slightly polysilane remains.
Δ: Some polysilane remains.
×… There is considerable polysilane remaining.

  According to Table 4, it turns out that the process of the polysilane in reaction container 100,600 is completed in a short time in order of Example 2, Example 1, and Comparative Example 2. FIG. Therefore, according to Examples 1 and 2, it can be seen that the amount of polysilane generated can be suppressed as compared with Comparative Example 2, and the cost for polysilane treatment can be suppressed.

(A) is typical front sectional drawing which shows an example of the deposited film formation apparatus of this invention, (b) is the XX sectional drawing. It is a schematic perspective view which shows the structure of the partition plate of the deposited film formation apparatus shown in FIG. It is a principal part expanded sectional view of an example of an electrophotographic photoreceptor. (A) is typical sectional drawing which shows the other example of the deposited film forming apparatus of this invention, (b) is the XX sectional drawing. It is typical front sectional drawing which shows an example of the conventional deposited film formation apparatus. (A) is typical front sectional drawing which shows the deposited film forming apparatus of the comparative example 1 of this invention, (b) is the XX sectional drawing. (A) is typical sectional drawing which shows the deposited film formation apparatus of the comparative example 2 of this invention, (b) is the XX sectional drawing.

Explanation of symbols

100,600 Reaction vessel 101,601 Discharge electrode 105,405,505 Exhaust piping (exhaust part)
206,606 Gas introduction pipe (gas introduction part)
107,607 Cylindrical base body 108,508 Rotating shaft 109,609 High frequency power supply 111, 211,411 Partition plate 112 Gas introduction hole (gas introduction portion)
113 Exhaust port (exhaust part)
700 Electrophotographic photoreceptor

Claims (3)

A reaction vessel having an exhaust part and a gas introduction part, in which a plurality of cylindrical substrates can be arranged, and capable of being vacuum-tight, constitutes a side wall of the reaction vessel, and the plurality of cylindrical substrates are arranged A deposited film forming apparatus for forming a deposited film on the surfaces of the plurality of cylindrical substrates, the discharge electrode provided so as to surround the position,
The deposited film forming apparatus is provided between positions where the plurality of cylindrical substrates are arranged so that surfaces of the plurality of cylindrical substrates do not directly face each other, and the discharge A partition plate electrically connected to the electrode ;
And wherein the partition plate has a cylindrical portion outlet constituting part of the exhaust portion is provided, and said cylindrical portion joined a plate portion about said cylindrical portion A deposited film forming apparatus. The deposited film forming apparatus according to claim 1 , wherein a gas introduction hole constituting a part of the gas introduction portion is provided in the vicinity of the discharge electrode of the partition plate. The deposited film forming apparatus according to claim 1, wherein the plurality of cylindrical substrates are four cylindrical substrates, and the partition plate has four plate portions.

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