JPS639219B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an electrophotographic photoreceptor,
More specifically, the present invention relates to an electrophotographic photoreceptor whose photoconductive layer is made of an amorphous material mainly composed of carbon and silicon. Conventionally, electrophotographic photoreceptors, such as amorphous
A photoreceptor made of Se or amorphous Se doped with impurities such as As, Te, Sb, or Bi, or a photoreceptor made of CdS or the like is used. These photoreceptors are extremely toxic, and amorphous Se crystallizes at temperatures above 100°C, resulting in very poor thermal stability, and the photoreceptor film has poor mechanical strength and liquid development resistance, making it difficult for electrophotography. It can be said that there are still many problems that need to be solved as a photoreceptor. Therefore, a photoreceptor with good photoconductivity that solves these problems has been desired. By the way, amorphous silicon produced by vapor deposition or sputtering that does not contain hydrogen has a dark resistivity.
Since it has a low photoconductivity of 10 ⁵ Ω·cm and an extremely low photoconductivity, it is not desirable as an electrophotographic photoreceptor. This is due to the fact that many Si-Si bonds are broken and there are many defects. That is, since the average density of states of localized levels in the energy gap is as high as 10 ²⁰ /cm ³ , the thermally excited carriers undergo hopping conduction, resulting in a low dark specific resistance.
Furthermore, conductivity deteriorates because photoexcited carriers are captured. On the other hand, for example, in non-doped amorphous silicon produced by glow discharge decomposition of silane (SiH ₄ ) gas, the dark specific resistance value is 10 ⁹ to ^{10 10} Ω・cm.
The report “Advances in Physics” (Vol.26,
No. 6, p. 312, published in 1977) and the report "Solid ^State
Communications” (Vol. 20, p. 969, published in 1976), the defects are compensated by hydrogen and the average density of states of localized levels in the energy gap is 10 ¹⁷ ~
Since the amount is as low as 10 ¹⁸ /cm ³ , the photoconductivity is extremely good and it is possible to control p-type and n-type valence electrons, but it is difficult to obtain a dark resistivity value sufficient for use as an electrophotographic photoreceptor. Reproducibility is low and extremely restrictive conditions are required. An object of the present invention is to provide a novel electrophotographic photoreceptor. Another object of the present invention is to have high dark resistance, thermal
An object of the present invention is to provide an electrophotographic photoreceptor having high chemical and mechanical strength and high photoconductivity. The object of the present invention is to provide silicon and carbon as main components on a conductive support (composition ratio C/Si is 5 to 5).
In an electrophotographic photoreceptor provided with a photoconductive layer made of an amorphous material containing 1 to 40 atom% of hydrogen and 0.01 to 20 atom% of fluorine, the photoconductive layer is close to the support. A doped layer doped with impurities is provided on the side so as to have one conductivity type, and a layer with a dark specific resistance of 10 ¹⁰ Ωcm is placed on top of this doped layer.
A structure in which the above layer is provided as the outermost surface area, or a second layer in which an impurity is further doped on the layer having the dark specific resistance value of 10 ¹⁰ Ωcm or more so as to have a conductivity type opposite to that of the doped layer. This is achieved by an electrophotographic photoreceptor characterized in that it has a structure in which a doped layer is provided. The reason for this is not clear, but as will be described later, it is presumed that the doped layer acts as a kind of barrier against charges injected from the support side. Crystalline silicon carbide is an extremely stable substance thermally, chemically, and mechanically, and is attracting attention as an electronic material for high temperature and high power use, as well as for its wide band gap and many crystalline polymorphisms, and as a material for light emitting devices. Development research has been conducted as In addition, amorphous silicon carbide was prepared by glow discharge decomposition in the report ``Phylosophical Magazine'' (Vol. 35, p. 1, published in 1977), and in the report ``Thin Solids Films'' (Vol. 2, published 1977) in which it was prepared by high-frequency sputtering.
From page 79, published in 1968), the former has a dark resistivity value of 10 ¹² Ω·cm or more at room temperature, and the latter has a value of 10 ⁸ Ω·cm. However, little research has been conducted on these photoconductivity properties, and therefore, in electrophotographic photoreceptors in which a photoconductive layer mainly composed of silicon and carbon is provided on a conductive support, it is difficult to determine the structure of this photoconductive layer. It is completely inconceivable that preferable electrophotographic properties can be obtained by changing the thickness in the thickness direction by doping with impurities. The present invention will be explained in detail below. In the present invention, a charge transport layer may be laminated on the surface of the photoconductive layer. In the present invention, the photoconductive layer is provided with a doped layer doped with impurities so as to have one conductivity type on the side close to the support, and a layer having a dark specific resistance value of 10 ¹⁰ Ωcm on the surface of this doped layer. (which may or may not be doped), or the doped layer (first doped layer) is further provided on a layer having a dark specific resistance value of 10 ¹⁰ Ωcm or more. It is necessary to provide a second doped layer doped with impurities so that it has a reverse conductivity type, so-called p(n)-i, or p-i-n (n-i-p). It has a structure. In the present invention, a conductive support is, for example, a plate or film made of an insulating material such as glass, ceramic, or synthetic resin. (inorganic compounds such as
or a plate, film, or foil made only of conductive materials. The shape of the support may be any shape, such as a plate, a belt, or a cylinder, and the shape is determined depending on the needs, but in the case of continuous high-speed copying, it may be an endless belt or a cylinder. It is desirable to do so. In the present invention, mainly carbon and silicon,
Further, a photoconductive layer made of an amorphous material containing hydrogen and fluorine can be formed on the support by a glow discharge decomposition method, a sputtering method, an ion implantation method, etc., and has desired electrophotographic properties. These methods are selected and adopted as appropriate depending on the factors, and it is also effective to use these methods in combination. The photoconductive layer is made of an amorphous material mainly composed of carbon and silicon, and further contains hydrogen and fluorine. and the amount of fluorine added. That is, in the glow discharge decomposition method, gases such as silane or silane derivatives such as SiH ₄ , Si ₂ H ₆ , SiCl ₄ , SiHCl ₃ ,
SiH ₂ Cl ₂ , SiF ₄ , Si(CH ₃ ) ₄ , etc., or gases obtained by diluting these gases with inert gases such as H ₂ , He, Ar, Ne, etc., and CH ₄ , C ₂ H ₂ , C _{2 H4 , C2H6} , _{C3H4 ,
C3H6} , _C3H8 , _{CH3F , CF4 , CH3Cl , C2H2F2 ,
C2H3F , C2ClF3} , _{C3F8 , CCl2F2 , CCl3F ,}
At least one gas such as organic gas such as C ₂ H ₃ Br, F ₂ , HF, BrF ₃ or fluorine-based gas is introduced into the glow discharge decomposition device and glow discharge is generated using high frequency or DC power. , the introduced gas is decomposed and reacted to form a photoconductive film. In addition, in the sputtering method, a single crystal or polycrystalline target material with a desired composition ratio of carbon and silicon, or a target material made of silicon or carbon alone is bombarded with ion bombardment such as Ar generated by high frequency or direct current glow discharge. A photoconductive film is formed by reacting the target composition with the above-mentioned organic gas, fluorine-based gas, or H ₂ gas introduced. Further, the well-known ion implantation method can also be used to form the film by implanting ions of silicon, carbon, hydrogen, fluorine, etc. into amorphous silicon or silicon carbide film. Mainly consisting of carbon and silicon in the present invention,
Furthermore, a photoconductive layer made of an amorphous material containing hydrogen and fluorine can be formed by the above method or a combination thereof, and the composition ratio C/Si of carbon and silicon is (5) atomic %. ~(100)
It has been found that hydrogen and fluorine are preferred in order to obtain a photoconductive layer with high dark specific resistance and good photoconductivity and electrophotographic photoreceptor properties. The amount of fluorine added to the amorphous material mainly composed of carbon and silicon is 0.01 atomic % to 20 atomic %, more preferably 0.5 atomic % to 10 atomic %. Further, the amount of hydrogen is 1 atomic % to 40 atomic %, more preferably 10 atomic % to 30 atomic %. In particular, the amount of hydrogen added can be controlled by controlling the temperature of the deposition substrate and/or the amount of the starting material used for adding hydrogen introduced into the system. Furthermore, after forming an amorphous layer mainly composed of carbon and silicon, the layer may be exposed to an activated hydrogen atmosphere. Further, at this time, one method is to heat the amorphous layer mainly composed of carbon and silicon to a temperature below the crystallization temperature. The conductivity type of amorphous materials, which are mainly composed of carbon and silicon and also contain hydrogen and fluorine, can be controlled by doping with impurities during manufacturing.
By changing the stacking order of the first doped layer, the non-doped layer, and the second doped layer, there is an advantage that the polarity of charging when forming an electrostatic image on the electrophotographic photoreceptor can be arbitrarily selected. This advantage is that when using a conventional, for example, Se-based photoconductive layer, the P-type can be changed depending on the manufacturing conditions such as the substrate temperature, the type of impurity, and its doping when forming the layer. or at most true type (type i)
This is much more advantageous than the need to strictly control the substrate temperature to form a P type. The impurities doped into the amorphous layer mainly composed of carbon and silicon and further containing hydrogen and fluorine include elements of group A of the periodic table, such as B, Al, Ga, In, Tl, etc. are listed as suitable ones, and in case of n-type,
Elements of group A of the periodic table, such as N, P, As,
Preferred examples include Sb and Bi. These impurities are contained in trace amounts, so
Although it is not necessary to pay as much attention to the pollution properties of the main materials constituting the photoconductive layer, it is preferable to use materials that are as non-pollution-prone as possible. From this point of view, the photoconductive layer to be formed is best made of, for example, B, As, P, Sb, etc., taking into account the optical properties. The amount of impurities doped into the amorphous layer, which is mainly composed of carbon and silicon and further contains hydrogen and fluorine, is determined as appropriate depending on the desired electrical and optical properties at a substrate temperature of 200 to 250°C. is a group A impurity, usually 10 ^-3 to 20 atomic %,
Preferably 10 ^-1 to 10 atomic %, in the case of group A impurities, usually 10 ^-3 to 30 atomic %, preferably
It is desirable that the content be 10 ^-1 to 20 atomic %. However, the doping amount varies depending on conditions such as substrate temperature, and is not limited to this. The method of doping these impurities is different from the manufacturing method of forming an amorphous layer mainly composed of carbon and silicon. For example, in the glow discharge decomposition method, B ₂ H ₆ , AsH ₃ , PH ₃ , Sbcl ₅ A gas such as the like is introduced and activated by glow discharge, and doping is performed by exposing the amorphous layer to an atmospheric gas during or after formation. Further, in the sputtering method, doping is performed in the same manner as in the glow discharge decomposition method, or doping is performed by sputtering single doping atoms at the same time. In the ion implantation method, ions of each doping atom may be implanted. The photoconductive layer in the present invention is made of an amorphous material mainly composed of carbon and silicon, and further contains hydrogen and fluorine, and the conductivity type of the non-doped film is slightly n-type. The structure of this photoconductive layer is a doped layer doped with impurities so that it becomes the first conductivity type from the side closest to the support, and a layer on the doped layer with a dark specific resistance value of 10 ¹⁰ Ω・cm or more. The basic structure is a so-called p(n)-i type structure, which is a stacked layer of layers (non-doped or doped with a small amount of doping and close to intrinsic), and further has a doped layer of the first conductivity type and a dark specific resistance value. It has a so-called p-i-n type (n-i-p type) diode structure consisting of a three-layer structure including a layer having a conductivity of 10 ¹⁰ Ω or more and a doped layer of a conductivity type opposite to the first conductivity type. The reason why the photoconductive layer configured in this manner exhibits a high dark specific resistance is considered as follows. That is, when the surface of the photoconductive layer is charged, charges of opposite polarity are induced on the surface of the support. When the charges on the surface of the support are injected into the photoconductive layer, they recombine with the majority carriers in the first doped layer on the side closer to the support, thereby acting as a barrier to suppress charge injection into the doped layer. I think that the.
Therefore, when the surface of the photoconductive layer is charged, in a two-layer structure, a charge of opposite polarity to the charge on the photoreceptor surface is induced, and this charge on the support side becomes a minority carrier with respect to the doped layer on the support side, and during injection. The polarity of the charge must be selected to recombine with the majority carrier. Therefore, it is desirable that the support-side doped layer is sufficiently doped. In addition, in a three-layer photoreceptor, a doped layer of opposite conductivity type to the doped layer on the support side is provided on the surface side of the photoreceptor to prevent electrical charges on the surface of the photoreceptor from being injected into the photoconductive layer. . In this case, it goes without saying that the charging polarity must be selected so that an electric field similar to the application of a reverse bias voltage in a diode element is formed in the photoconductive layer. Furthermore, since the non-doped layer is slightly n-type, it is also possible to make it intrinsic by doping a small amount of group A atoms. The layer thicknesses of the first and second doped layers and the layer having a specific resistance value of 10 ¹⁰ Ω·cm or more of the photoconductive layer in the present invention are appropriately determined depending on the desired electrophotographic properties and usage conditions, In this case, the doped layer is 0.005 micron to 0.3 micron, preferably 0.01 micron to 0.1 micron, and the undoped layer is 0.1 micron to 100 micron, preferably 0.3 micron to 50 micron. The charge transport layer in the present invention is a transport layer for photoexcited carriers in a so-called functionally separated electrophotographic photoreceptor, and has a dark specific resistance of 10 ¹⁰ Ωcm or more and is itself almost photoconductive to visible light and infrared light. It has no properties and is a good conductor for electron or hole carriers.
It is made of a crystalline or amorphous inorganic semiconductor material, and has an optical window effect on the photoconductive layer when image exposure is performed from the charge transport layer side, for example, For example, inorganic semiconductors with an optical absorption edge of 1.5 eV or more include oxide semiconductors and chalcogenite semiconductors. What is desired for a charge transport layer laminated with a photoconductive layer is that no barrier or interface level is created at the interface between the photoconductive layer and the charge transport layer for electrons or hole carriers that are photoexcited in the photoconductive layer. These carriers are efficiently injected from the photoconductive layer into the charge transport layer, and the carriers have high mobility and lifetime in the charge transport layer, and are not captured and can efficiently reach the surface of the electrophotographic photoreceptor. be. Here, the oxide semiconductor is
In ₂ O ₃ , TiO ₂ , SnO ₂ , ZnO, PbO, etc. includes materials containing S, Te, and Se. The inorganic semiconductor serving as the charge transport layer can be produced by conventional vapor deposition, sputtering, glow discharge decomposition, as well as coating, spraying, and the like. In addition, after laminating the charge transport layer, the temperature is set at 50°C to 400°C to improve electrical bonding at the interface between the photoconductive layer and the charge transport layer.
C. heat treatment may be performed. The layer thickness of the charge transport layer in the present invention is from 0.5 micron to 50 micron, particularly from 0.5 micron to 10 micron. The antireflection film used in the present invention is a film that prevents light reflection from occurring on the surface of the photoconductive layer during exposure, thereby reducing the amount of light absorbed by the photoconductive layer and increasing the light loss rate. It may be an insulating material that does not adversely affect various properties required for an electrophotographic photoreceptor and also serves as the charge transport layer. The layer thickness of the surface protective layer or antireflection film may be λ/4√ (where n is the refractive index of the photoconductive layer and λ is the wavelength of the exposure light) or an odd multiple thereof, and is 0.05 to 50 microns. be. The material for forming the antireflection film is the same as that for the charge transport layer, and is formed by methods such as vapor deposition, sputtering, and coating. Next, a case in which the electrophotographic photoreceptor of the present invention is manufactured particularly by a glow discharge decomposition method will be described with reference to FIG. 1, which is a conceptual diagram of a typical capacitively coupled glow discharge decomposition apparatus. To explain the present invention with reference to FIG. 1, a capacitively coupled glow discharge decomposition device
100 vacuum chamber 123 has a glow discharge electrode 101
A substrate support member and a substrate heating member 102 are placed facing each other at a predetermined interval above the photoconductive layer, and a substrate 103 on which the photoconductive layer is to be formed is fixed to the substrate support member 102. Further, the glow discharge electrode 101 is electrically connected to a high frequency power source 104, and when high frequency power is applied, glow discharge is generated mainly in the space between the glow discharge electrode 101 and the substrate 103. . A gas introduction pipe is connected to the vacuum chamber 123, and gas cylinders 116, 117, 118, 119
Therefore, each gas flow meter 112, 113, 11
4,115 through the needle valve 108,1
09, 110, and 111, a predetermined gas is introduced into the vacuum chamber 123 while controlling the flow rate. Further, a filter 107 and a needle valve 106 are installed in the gas introduction system to remove particles in the gas. Furthermore, vacuum chamber 1
At the bottom of 23, an exhaust device is installed via a diffusion pump valve 122 and a rotary pump valve 121. Substrate 1 using the glow discharge decomposition device shown in Figure 1.
In order to form a photoconductive layer made of a desired amorphous material mainly composed of carbon and silicon on the substrate 103, the substrate 103, which has been physically or chemically cleaned, is first fixed to the supporting member and the heating member 102. . Next, the vacuum chamber 123 is evacuated to a back pressure of preferably 1×10 ^-5 torr or less using an exhaust device, the substrate temperature is maintained at a predetermined level using a substrate heating member, the diffusion pump valve 122 is closed, and the rotary pump valve 123 is closed. Open and exhaust only with the rotary pump. And gas cylinders 116, 117, 11
Needle valve 106, 108 from 8,119,
Flow meters 112, 1 by 109, 110, 111
13, 114, and 115, a predetermined gas is introduced while controlling and monitoring the flow rate. Here, the cylinders 116 and 117 are filled with a raw material gas that forms an amorphous photoconductive layer mainly composed of carbon and silicon, and include the above-mentioned silane or silane derivative gas or its dilution gas, and the above-mentioned organic It may be a gas, a fluorine-based gas, or a mixed gas thereof. Also, cylinders 118 and 119 are PH ₃ or
Filled with doping gas such as B ₂ H ₆ . The composition ratio of carbon and silicon or the doping impurity of the amorphous photoconductive layer mainly composed of carbon and silicon can be arbitrarily varied by controlling the flow rate, and can also be changed in the film thickness direction. The tube is installed in such a way that sufficient gas reaches the space between the outlet substrate 103 of the gas introduction tube into the vacuum chamber and the glow discharge electrode 101, and the tube is installed in a ring shape near the glow discharge electrode 101 to generate a gas flow. You can let me. Next, the rotary pump valve 121 is adjusted to maintain the back pressure of the vacuum chamber 123 at a degree of vacuum of 10 ^-2 Torr to 10 Torr, and a high frequency voltage is applied from the high frequency power supply 104 to the glow discharge electrode 101 to generate glow discharge. The appropriate frequency of the high frequency to be applied to the glow discharge electrode 101 is 0.1 MHz to 50 MHz. Here, the voltage applied to the glow discharge electrode 101 may be a DC voltage and is suitably 0.3KV to 5KV. Moreover, a substrate supporting member and a substrate heating member 1
02 may be grounded, but may be negatively biased to 50V to 500V to avoid collision of secondary electrons due to glow discharge. Furthermore, although the glow discharge decomposition apparatus 100 is of a capacitive coupling type,
It may be of an inductively coupled type in which a coiled glow discharge electrode is arranged outside. In addition, in the sputtering method, an apparatus having a structure similar to that shown in FIG. 1 can usually be used, and a target material having a desired composition ratio is placed on the glow discharge electrode shown in FIG. 1, and high frequency or DC sputtering is performed. When doping with impurities, a doping gas may be introduced in the same manner as in the glow discharge decomposition method. In the present invention, it is preferable that the temperature of the substrate 103 be in the range of 50°C to 350°C, more preferably 100°C to 300°C when performing the glow discharge decomposition. Maintaining the substrate temperature is achieved by the substrate support member and substrate heating member 102. The deposition rate of the photoconductive layer is also a factor that supports the physical properties of the photoconductive layer, and is usually preferably 0.5 to 1000 Å/sec, but can also be increased to 1000 Å/sec or more. An electrophotographic photoreceptor according to the present invention having a photoconductive layer made of an amorphous material mainly composed of carbon and silicon and further containing hydrogen and fluorine is shown in FIGS. 2 to 4. In FIG. 2, 200 is an electrophotographic photoreceptor, 20
Reference numeral 1 denotes a conductive support, which consists of a support 202 and a conductive layer 203; however, if the support itself is conductive, the conductive layer 203 is not necessarily required. 204 is a photoconductive layer formed by the method of the present invention and made of an amorphous material mainly composed of carbon and silicon and further containing hydrogen and fluorine; doped layer 20
Consists of 5. and surface 208 of photoconductive layer 204
By positively or negatively charging the conductive support 201 and transferring the positively or negatively charged latent image formed by imagewise exposure using liquid development, cascade development, or magnetic brush development, a Hikyu copy can be obtained. Can be done. On the other hand, in the other embodiment shown in FIG.
5. Non-doped layer or intrinsically doped layer 306, second doped layer 307 of opposite conductivity type to the first doped layer
It consists of In the embodiment of FIG. 4, the photoconductive layer 404 is similar to the photoconductive layer of FIG. It is something. As described above, the present invention provides a new electrophotographic photoreceptor that is harmless and fully satisfies the various conditions required for an electrophotographic photoreceptor. The present invention can also be applied as photoelectric conversion electronic materials such as light receiving elements and solar cells. The present invention will be explained in more detail with reference to Examples below. Example 1 A 0.1 micron thick Ni conductive layer was attached to the upper surface of a slide glass support by high frequency sputtering using the capacitively coupled glow discharge decomposition apparatus shown in FIG. A photoconductive layer was provided to produce an electrophotographic photoreceptor in the embodiment shown in FIG. An amorphous layer mainly composed of carbon and silicon and further containing hydrogen and fluorine as a photoconductive layer was produced under the following conditions by controlling the introduction of SIH ₄ , Ar, and CF ₄ gases. (Introduced gas) ●SiH ₄ (diluted with Ar, 10.7%) gas flow rate
~140c.c./min ● _CF4 gas ~ _CF4 / _SiH4 partial _pressure ratio = 1.1 ● _B2H6 (diluted with Ar, 10.5%) gas ~2% by volume (other conditions) ●Back pressure of vacuum chamber ~6×10 ^-6 torr ●High frequency frequency and power
~13.56MHz, 70W (0.29W/ ^m2 ) ●Substrate temperature ~220℃ ●Deposition rate ~280Å/min ●Degree of vacuum during discharge ~0.4torr ●Distance between cathode and substrate ~2.3cm The photoconductive layer is first conductive on the support under the above conditions,
A 500 Å B-doped layer was deposited by glow discharge decomposition of a gas mixture of SiH ₄ , CF ₄ and B ₂ H ₆ . This P
It was found from ESCA analysis and conductivity measurement of the B-doped single layer that the composition ratio C/Si of the mold layer was 0.22, and the dark conductivity was (1.5×10 ⁻³ )Ω ⁻¹ ·cm ⁻¹ . Furthermore, by introducing SiH ₄ , Ar, and CF ₄ gases, a non-doped layer of 5 microns was deposited to complete an electrophotographic photosensitive plate. Using this photosensitive plate, first, the surface of the photosensitive plate was charged by 8KV corona discharge, and 1.7lux was charged.
The light attenuation characteristics of the surface potential were measured by irradiating the surface with halogen lamp light of 0.15 lux, and the results shown in Table 1 were obtained.

[Table] Where, Vo: Surface potential before lightning (Volt) ε〓/I: Initial light attenuation rate of surface potential (Volt/μ・
sec・lux) E1/2; half-decreased exposure amount (lux・sec) When comparing this electrophotographic photoreceptor with an electrophotographic photoreceptor in which the photoconductive layer is composed only of a non-doped layer, it is found that electron injection from the conductive layer is hindered and the former The dark decay rate has been reduced to 1/2. An electrostatic latent image was formed on this photosensitive plate by image exposure at 5 lux/sec, then developed with toner using a liquid development method, and then transferred and fixed onto transfer paper, resulting in a clear image with high image density and no fogging. I was able to get it. Example 2 On a conductive substrate similar to that described in Example 1, an electrophotographic photoreceptor in the embodiment shown in FIG. 3 was produced.
B and P doping to the amorphous material of the photoconductive layer, which is mainly composed of carbon and silicon and further contains hydrogen and fluorine, was carried out using B 2 H 6 and B ₂ H ₆ under the same manufacturing conditions as in Example 1.
The concentrations of PH ₃ were 2% by volume and 1% by volume, respectively. First deposit a B-doped layer of 450 Å, then a 5 micron undoped layer, then a 450 Å P-doped layer.
This was adhered to form a pin structure to produce an electrophotographic photoreceptor. Comparing this electrophotographic photoreceptor with the P-i configuration of Example 1, it is found that n
By providing the layer, the charging potential increased by 20 to 30% because hole injection at the surface was prevented. This photosensitive plate was charged and subjected to image exposure at 3 lux/sec to form an electrostatic latent image, which was then developed with toner using a cascade development method, and then transferred and fixed onto transfer paper, resulting in high image density and fog. We were able to obtain clear images without any blemishes. Example 3 On a conductive substrate similar to that described in Examples 1 and 2, under the same manufacturing conditions as in Examples 1 and 2, a photoconductive material having an n-i-p configuration opposite to that of Example 2 was produced. An electrophotographic photoreceptor provided with layers was produced. First, 1% by volume of PH ₃ gas was introduced into the n-type layer, and SiH ₄ , CF ₄ and
Glow discharge decomposition with Ar gas mixture,
430 Å was deposited. The dark conductivity of this n-type layer is (1.0×
10 ^-5 ) Ω ^-1・cm ^-1 and has a sufficiently large electron carrier concentration. Next, a non-doped layer of 4 microns and a B-doped P-type layer containing 8 volume % of B ₂ H ₆ concentration and 640 Å were deposited to form an n-i-p configuration, and an electrophotographic photosensitive plate was fabricated. . Using this photosensitive plate, the surface of the photosensitive plate was first charged by 8KV corona discharge, 1.7lux and 0.15lux halogen lamp light was irradiated to measure the light attenuation characteristics of the surface potential, and the second
Obtained the results in the table.

[Table] Using this photosensitive plate, first charge the surface of the photosensitive plate with 8KV corona discharge and charge it for 10lux・sec.
After imagewise exposure was performed to form an electrostatic latent image, the image was transferred and fixed to , and a clear image with high image density and no fogging could be obtained. Example 4 B ₂ H ₆ was first deposited on an Al substrate under the same conditions as Example 1.
A P-type layer of 500 Å and a non-doped layer of 1.3 microns were deposited by glow discharge decomposition to form a photoconductive layer of an amorphous material mainly composed of carbon and silicon and further containing hydrogen and fluorine. Then, an electrophotographic photoreceptor of the embodiment shown in FIG. 4 was produced, in which a charge transport layer made of an inorganic semiconductor was provided on the photoconductive layer. The charge transport layer is made of amorphous silicon carbide, which exhibits slightly n-type conductivity, with SiH ₄ gas, CH ₄ gas, and
By glow discharge decomposition in a mixed Ar gas,
After the photoconductive layer was deposited, it was formed under the following conditions without breaking the vacuum. (Introduced gas) ●SiH ₄ (diluted with Ar, 10.7%) gas flow rate
~140c.c./min ● _CH4 gas ~ _CH4 / _SiH4 partial pressure ratio = 4.5 (other conditions) ●High frequency frequency and power
~13.56MHz, 70W (0.29W/ ^m2 ) ●Substrate temperature ~220℃ ●Deposition speed 350Å/min ●Degree of vacuum during discharge 0.5torr The charge transport layer was deposited to a thickness of 2 microns on an electrophotographic photosensitive plate. completed. The composition ratio of amorphous silicon carbide was Si _0.58 C _0.42 , the optical absorption edge was 2.4 eV, and the amorphous layer of the photoconductive layer showed a sufficient window effect for 1.75 eV. When this photosensitive plate was charged and the light attenuation characteristics of the surface potential were measured, the initial charge potential was
The initial optical attenuation characteristic of the surface potential increases to 250V.
3.5Volt/ for 1.7lux halogen lamp light
μ·sec·lux, it was found to have excellent properties as a photosensitive plate, and to have extremely high mechanical strength and liquid development resistance. After forming an electrostatic latent image on this photosensitive plate by image exposure at 10 lux/sec, it was developed with toner using a liquid development method, and then transferred and fixed onto transfer paper. The image density was high, there was no fog, and there was no fog. I was able to obtain an image with clear tones.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram of a glow discharge decomposition apparatus for carrying out the present invention, FIG. 2 is a sectional view of a photoreceptor according to the present invention, and FIGS. 3 and 4 are photoreceptors according to other embodiments of the present invention. FIG. 200,300,400~electrophotographic photoreceptor, 2
01,301,401~Electroconductive support, 202,
302,402~Support, 203,303,40
3 - conductive layer, 204,304,404 - photoconductive layer, 205,305,405 - first doped layer,
206, 306 - Non-doped layer, 307 - Second doped layer, 208, 308, 408 - Photoreceptor surface, 409 - Antireflection layer or charge transport layer.

Claims (1)

[Scope of Claims] 1 Mainly composed of silicon and carbon (composition ratio C/Si is 5 to 100 at%) on a conductive support, further containing 1 to 40 at% of hydrogen and 0.01 to 20 at% of fluorine.
In an electrophotographic photoreceptor provided with a photoconductive layer made of an amorphous material containing, a doped layer doped with an impurity so as to have one conductivity type is provided on the side where the photoconductive layer is close to the support, A structure in which a layer with a dark specific resistance value of 10 ¹⁰ Ωcm or more is provided as the outermost layer on this doped layer, or the above dark specific resistance value is
10 A second layer doped with an impurity so as to have a conductivity type opposite to that of the doped layer is formed on the layer of ¹⁰ Ωcm or more.
An electrophotographic photoreceptor characterized in that it has a structure in which a doped layer is provided. 2. The electrophotographic photoreceptor according to claim 1, characterized in that an antireflection layer or a charge transport layer is laminated on the photoconductive layer.