JPS63208060A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body which has a high traveling property of a carrier and has high resistance and excellent electric charge characteristic by using the superlattice structure constituted by laminating thin layers having optical band gaps different from each other on a photoconductive layer. CONSTITUTION:The photoconductive layer 3 is constituted of an electric charge generating layer 6 and an electric charge holding layer 5. The charge generating layer 6 contains at least either of amorphous silicon and fine crystal silicon. The charge holding layer 5 is constituted by alternately laminating thin amorphous silicon films contg. at least one kind of element selected from carbon, oxygen and nitrogen and thin fine crystalline silicon films. The degrees of crystallization of the thin fine crystalline silicon films are changed in each of the thin films in the layer thickness direction. These thin films vary in the optical band gaps and the respective thicknesses thereof are in a 30-200Angstrom range. The excellent traveling property of the carrier and high photoconductive characteristics are thereby obtd. and a sharper image is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an electrophotographic photoreceptor having excellent charging characteristics, dark decay characteristics, photosensitivity characteristics, environmental resistance, and the like.

[Prior Art] Amorphous silicon containing hydrogen (H)'e gold (hereinafter abbreviated as a-8t:H) has recently attracted attention as a photoelectric conversion material, and is used in solar cells, thin film transistors, and images. In addition to sensors, it is applied to photoreceptors in electrophotographic processes.

Conventionally, inorganic materials such as CdS, ZnO, Ss, or 5e-Te, or yje! J-N-vinylcarbazole (
pvcz ) or trinitrofluorenone (TNF
) and other organic materials were used. However, a-
Compared to these inorganic or organic materials, 81:H is a non-polluting substance and does not require recovery treatment, has high spectral sensitivity in the visible light region, and has a high surface hardness and wear resistance. It has advantages such as excellent impact resistance. For this reason, a-81:H is attracting attention as a photoreceptor device for electrophotographic processes.

This a-8i:H is being studied as a photoreceptor material based on the Carlson method, but in this case, high resistance and photosensitivity are required as photoreceptor characteristics. However, since it is difficult to satisfy both of these characteristics with a single photoreceptor, a barrier Wi is provided between the photoconductive layer and the conductive support, and a gold film is formed as a surface charge retention layer on the photoconductive layer. These requirements are satisfied by creating a multi-layered structure.

[Problems to be Solved by the Invention] By the way, a-8i:H is usually formed by a glow discharge decomposition method using all silica/based gases, but at this time,
a-8i: Hydrogen is incorporated into the H film, and the electrical and optical characteristics vary greatly due to the difference in hydrogen concentration. That is, a-
As the amount of hydrogen that enters the 8i:H film increases, the optical bandgap becomes larger and the resistance of a=81:H increases, but as a result, the photosensitivity to long wavelength light decreases. For example, it is difficult to use it in a laser beam printer equipped with a semiconductor laser. In addition, when the amount of hydrogen in the a-8i:H film increases, depending on the film formation conditions, those with bonding structures such as (SiH2)n and 5iH7 may occupy most of the area in the film. . In this case, the photoconductive properties are deteriorated due to the increase in DET and the increase in silicon dangling.
It becomes unusable as an electrophotographic photoreceptor.

Conversely, as the amount of hydrogen incorporated into a-8l:H decreases, its optical bandgap becomes smaller9, its resistance decreases, but its photosensitivity to longer wavelength light increases.

However, when the hydrogen content is low, there is less hydrogen to reduce the silicon dangling bond bonding. Therefore, the mobility of the generated carriers decreases,
As the lifespan becomes shorter, the photoconductive properties deteriorate,
This makes it difficult to use as an electrophotographic photoreceptor.

In this way, the photoconductive layer of the electrophotographic photoreceptor can be formed into a single a-8
If it is composed of only the 1:H layer, there is a problem that the characteristics change greatly depending on the manufacturing conditions of a-81:H,1, and desired characteristics cannot be obtained.

The present invention was made in view of the above circumstances, and the purpose is to provide an electrophotographic photoreceptor that has good adhesion to a substrate and excellent environmental resistance.

[Structure of the Invention] (Means for Solving the Problems) As a result of various studies, the present inventors have constructed a photoconductive layer of an electrophotographic photoreceptor consisting of a charge retention JζJ and a charge generation layer. , 'JfftJ of a plurality of predetermined semiconductor films in the charge retention layer.
The present inventors have discovered that the above object can be achieved by forming a region having a superlattice structure.The present invention has thus been completed.

That is, the electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor comprising an electrically conductive support and a photoconductive layer, the photoconductive layer comprising a charge generation layer and a charge retention layer, The generation layer includes one of amorphous silicon and microcrystalline silicon, and the charge retention layer includes an amorphous silicon thin film containing at least one element selected from carbon, oxygen, and nitrogen, and microcrystalline silicon. The microcrystalline silicon thin film is characterized in that the degree of crystallinity of the microcrystalline silicon thin film varies from film to film in the layer thickness direction.

The microcrystalline silicon (μc-8t) used in the present invention is thought to be formed by a mixed layer of microcrystalline silicon and amorphous silicon with a grain size of about several tens of Angstroms, It has the following physical characteristics.

First, in X-ray diffraction measurements, it is clearly distinguished from the amorphous a-8t in which only a halo appears, which is the entire crystal diffraction pattern where 2θ is around 28 to 28.5°. Second, μc
The dark resistance of −8i can be adjusted to 1(10)0Ω·m or more, and it is clearly distinguished from polycrystalline silicon, which has a dark resistance of 1050Ω·m.

The optical bandgap (Eg') of the μc-8i used in the present invention is preferably 1.55 eV, for example. However, it can be set arbitrarily within a certain range. In order to obtain the desired Eg"e, it is preferable to add the required amount of hydrogen to each and use it as μc-8l:H. This compensates for the dangling focus of silicon and balances the dark resistance and bright resistance. , photoconductive properties are improved.

Note that an actual μc-8i film often takes on a weak P-type or N-type (especially easily becomes an N-type) depending on specific factors such as manufacturing conditions. Therefore, in order to obtain the type 1 required for forming the entire superlattice structure, it is desirable to lightly dope impurities having opposite conductivity types to cancel out the P type or N type.

The crystallinity of the microcrystalline silicon thin film constituting the charge retention layer is preferably 60 to 90, more preferably 60 to 80.
It is best to vary it within the range of .

(Function) In the electrophotographic photoreceptor of the present invention, since the photoconductive layer is provided with the superlattice structure, carriers generated in this region have a long life and a high mobility. Although the theory has not yet been fully established, there is no doubt that this is a quantum effect due to the periodic well potential characteristic of the superlattice structure, and this is particularly referred to as the superlattice effect.

In this way, carrier mobility in the photoconductive layer increases,
Furthermore, the sensitivity of the electrophotographic photoreceptor is significantly improved due to the longer life of the carrier.

(Example) FIG. 1 is a diagram showing a cross-sectional structure of an electrophotographic photoreceptor according to an example of the present invention. In the figure, conductive support 1
A barrier layer 2 is formed thereon, and a photoconductive layer 3 consisting of a charge retention layer 5 and a charge generation layer 6 is formed thereon.

Moreover, the surface Nl! 4 is formed. Note that both the charge retention layer 5 and the charge generation layer 6 have a superlattice structure.

Hereinafter, the structure of the electrophotographic photoreceptor shown in FIG. 1 will be explained in more detail.

The conductive support 1 usually consists of a drum made of aluminum.

The barrier layer 2 may be formed of μc-8i or a-81:H kumquat, or may be formed entirely of a-BN:H (amorphous boron to which nitrogen and hydrogen are added), or may be formed of an insulating film. may also be used. For example, μc-8i:H and a
-8t: A high-resistance insulating barrier layer can be formed by completely containing at least one element selected from carbon, Cl, nitride, N, and 0 oxygen.

The thickness of the barrier layer 2 is preferably 100 μm to 10 μm.

The barrier layer 2 is formed to enhance the charge retention function of the surface of the photoreceptor by suppressing the flow of charges between the conductive support 1 and the charge generation layer 5, thereby increasing the charging ability of the photoreceptor. It is something that will be done. Therefore, when a Carlson type photoreceptor is constructed using a semiconductor layer as a barrier I-, the barrier layer 2 is
is P type or N type. That is, when the surface of the photoreceptor is positively charged, the barrier J@2'i P type is used to prevent electrons that neutralize the surface charge from being injected into the charge generation layer.

Conversely, when the surface is negatively charged, the barrier layer 2 is made of N type,
This prevents holes that neutralize surface charges from being injected into the charge generation layer. Since the carriers injected from the barrier J@2 become noise to the carriers generated in the charge generation layer 6 by the incidence of light, preventing carrier injection as described above improves the sensitivity. In addition, , 4a-8
1:H or a-81:H'iP type elements belong to Group Ⅰ of the periodic table, such as boron B, aluminum At, gallium GIL? It is preferable to perform total doping such as indium (In) and thallium (Tt). In addition, in order to make μc-8l:H or a-81:H N-type, it is necessary to dope it with elements belonging to Group V of the periodic table, such as nitrogen, phosphorus P1 boron As, antimony Sbs, and bismuth Bi. is preferred.

The charge generation layer 6 generates carriers when light is incident thereon, and carriers of one polarity neutralize the charges on the surface of the photoreceptor, while the other carriers retain the charges and travel within the ring 5. The conductive support 1 is reached.

The charge retention layer 5 is constructed by alternately laminating two types of thin layers. These thin layers have different optical bandgaps and each have a thickness in the range of 30-200X. In this way, by stacking thin layers with mutually different optical bandgaps, the optical bandgap can be made larger based on the layer with the smaller optical bandgap, regardless of the size of the optical bandgap itself. A superlattice structure with periodic potential barriers is formed in which the layers act as barriers. In this superlattice structure, since the thin barrier layer is extremely thin, carriers pass through the barrier and travel through the superlattice structure due to the carrier tunneling effect in the thin layer. Furthermore, in such a superlattice structure, a large number of carriers are generated by incident light. Therefore, it has high photosensitivity. Note that by changing the bandgap and layer thickness of the thin layer having the superlattice structure, the apparent bandgap of the layer having the Peter junction superlattice structure can be freely adjusted.

a-8i constituting the charge retention layer 5 and charge generation layer 6:
The hydrogen content in H and μc-81:H is 0.
(10) to 30 atoms are preferred, and 1 to 25 atoms are more preferred. Such a hydrogen content compensates for silicon dangling, brings the dark resistance and bright resistance into balance, and improves the photoconductive properties.

a-8t: H layer e To form a film by the glow discharge decomposition method, silane gases such as 5IH4 and S1□H5 are introduced into the reaction chamber as raw materials, and glow discharge is performed using high frequency to form a thin layer. Hi can be added.

If necessary, hydrogen or helium gas can be used as a carrier gas for silanes.

On the other hand, silica halides such as %5IF4 gas and 5icz4 gas can be used as the source gas. Furthermore, a-8l:H containing Hi gold can be similarly formed by reacting with a mixed gas of silane gas and silicon halide gas. Note that, instead of using the glow discharge decomposition method, the entire thin layer can also be formed by a physical method such as sputtering.

Similarly to a-8i:H, the μc-8i layer can also be formed using silane gas as a raw material by the high-frequency glow discharge decomposition method. In this case, the temperature of the support f a-8l
: When forming H, if the shi is set higher and the high frequency power is also set higher than in the case of a-8t:H, then μc-8
t:H becomes easier to form. Furthermore, by increasing the support temperature and high-frequency power, the total flow rate of raw material gas such as silane gas can be increased, and as a result, the film formation rate can be increased. In addition, by using all gases prepared by diluting high-order silanes such as SiH4 and 512H6 with hydrogen, μe-st: Hi-71
4. Can be formed with high efficiency.

μc-81: H and a-8t: Hf To make the P type, elements belonging to Group Ⅰ of the periodic table, such as boron B, aluminum At, gallium Ga, indium In, and thallium Tt @ 'f Preferably doped, μc-8l: H and a-8l:
To make Hf n-type, an element belonging to Group V of the periodic table, for example i! , Ni'7-Nt Phosphorus P, Arsenic Al
l, antimony Sb.

It is preferable to dope with bismuth B1 or the like.

This doping with p-type impurities or n-type impurities prevents charge from transferring from the support side to the photoconductive layer. On the other hand, by incorporating at least one element selected from carbon C2 nitrogen N and oxygen O into μc-8i:H and a-8i:H, high resistance can be achieved and the surface charge retention ability can be improved. can be increased. The content of these elements is 5 to 40 atoms, preferably 10 to 30 atoms.

A surface layer 4 is provided on the charge generation layer 6.

Since the refractive index of a-81:H of the charge generating J-piece 6 is relatively large at 3 to 3.4, light reflection easily occurs on the surface. When such light reflection occurs, the proportion of the amount of light absorbed by the photoconductive layer or the charge generating layer decreases, increasing light loss. For this reason, it is preferable to provide a surface /li 4 to prevent reflections. Note that by providing the surface layer 4, charge generation/#6 is protected from damage. Furthermore, by forming the surface layer, the charging ability is improved, and the charge can be easily deposited on the surface. The materials for forming the surface/fjw are a'-8IN: H, a''-810:
H, and a-8iC: There are inorganic compounds such as H and organic materials such as polyvinyl chloride and polyamide.

When the surface of the electrophotographic photoreceptor constructed in this manner is charged with a positive voltage of about 500 V by corona discharge, a potential barrier is formed. When light (hv) is incident on this photoreceptor, carriers of electrons and holes are generated in the charge generation layer 6. Electrons in this conduction band are moved by the electric field in the photoreceptor,
The holes are accelerated toward the surface layer 41iIII, and the holes are accelerated toward the conductive support 1 side. In this case, in the potential well layer with a superlattice structure constituting the charge retention layer 5, due to quantum effects, the lifetime of carriers is 5 to 10 times longer than in the case of a single layer without a superlattice structure. .

In addition, in the superlattice structure, a p1 periodic barrier layer is formed due to bandgap discontinuity, but carriers easily pass through the bias layer due to the tunnel effect.
The effective mobility of the carrier is equivalent to that in the bulk, and the carrier has excellent mobility. As mentioned above,
A superlattice structure in which thin layers with different optical band widths are laminated makes it possible to obtain high photoconductivity and to obtain clearer images than conventional photoreceptors.

Below, with reference to FIG. 2, an apparatus and a manufacturing method for manufacturing the electrophotographic photoreceptor of the above embodiment by a glow discharge method will be fully explained. In the same figure, gas cylinder 21 t 22 *
23 s 24, for example, 5IH4°B2H6
# B2 t Contains raw material gas such as CH4.

Are these Su? The gas in the chamber is passed through pulp 26 for flow rate adjustment.
and is supplied to the mixer 28 through all of the piping 27. Each cylinder is equipped with a pressure gauge 25.
By adjusting the pulp 26f while monitoring the pressure gauge 25, the flow rate and mixing ratio of each raw material gas supplied to the mixer 28 can be adjusted.

The gases mixed in the mixer 28 are supplied to a reaction vessel 29. At the bottom 31 of the reaction vessel 29, there is a rotating Il'llll
30 is mounted rotatably around the vertical direction.

A disk-shaped support 32 is fixed to the upper end of the rotating shaft 30 with its surface perpendicular to the rotating shaft 30. Reaction container 29
Inside, a cylindrical electrode 33 is installed on the bottom 31 with its axial center aligned with the axial center of the rotating shaft 30. A drum base 34 of the photoreceptor is placed on a support base 32 with its axial center aligned with the axial center of the rotating shaft 3°, and a heater 35 for heating the drum base is arranged inside the drum base 34. It is set up. A high frequency power source 36 is connected between the electrode 33 and the drum base 34 so that a high frequency current is supplied between the electrode 33 and the drum base 34. The rotating shaft 3o is rotated and driven by a motor 38.

The pressure inside the reaction vessel 29 is monitored by a pressure gauge 37, and the reaction vessel 29 is connected via a dart valve 38 to a suitable evacuation means such as a vacuum pump.

When manufacturing a photoreceptor using the above-mentioned manufacturing apparatus, after installing the drum base 34 in the reaction container 29, the dart valve 39 is opened and the inside of the reaction container 29 is heated to about 0.1 Torr.
Evacuate to below pressure. Next, Zenpe 21.22.2
3924 and the necessary reaction mixtures are mixed at a predetermined mixing ratio and introduced into the reaction vessel 29.

In this case, the gas flow I introduced into the reaction vessel 29 has a pressure within the reaction vessel 29 of 0.1 to 1. Set it to OTorr. Next, the motor 38 is operated to rotate the drum base 34, the heater 35 heats the drum base 34 to a constant temperature, and the high frequency power supply 36 supplies high frequency current between the electrode 33 and the drum base 34. A glow discharge is formed between the two. As a result, a-8t:H is deposited on the drum base 34. In addition,
The raw material is in a bath with N20°NH3, No□lN2. CH4,
By using C2H4,0□, etc., carbon-1
, oxygen, and nitrogen can be contained in a-81:H.

As described above, the electrophotographic photoreceptor according to the present invention can be manufactured using a closed system manufacturing apparatus, and therefore is safe for the human body.

Next, the results of testing the electrophotographic properties of an electrophotographic photoreceptor according to the present invention formed into a film will be described.

Test Example 1 If necessary, in order to prevent interference, an aluminum drum base with a diameter of 80 mm and a width of 350 m, which has been subjected to acid treatment, alkali treatment, and sandblasting, is installed in the reaction vessel. The vacuum was evacuated to approximately 10-5 Torr.

The drum base was heated to 250°C and rotated at 10 rpm, while SiH4 gas was heated at 500 SCCM 1B2T (
6 gas was introduced into the reaction vessel at a flow rate ratio of 10 to SiH4 gas, and the pressure in the reaction vessel f I
Torr K adjusted. Then, high frequency power of 13.56 MHz was applied to generate plasma to form a p-type a-8iC:H barrier layer on the drum substrate.

Next, SiH4 gas was added to 500 SCCM, )12
250 SCCM of gas, 30 SCC of CH4 gas
The flow rate of 120X was introduced at a flow rate of M, the temperature was set to f I Torr in the reaction vessel, and a high frequency power of 400W was applied.
IC: A thin H layer was formed. Then, 5IH4 gas 16
0800M% H2 gas was introduced at a flow rate of 600 SCCM, the pressure inside the reaction vessel was set to 1.2 Torr, and a high frequency power of 1.2 kW was applied to form a 120X μc-8t:HFIJ layer. Such operations were repeated to form a charge retention layer having a superlattice structure of 12 μm. In addition, when forming the μc-81:H thin layer,
S for each thin layer formed! The H4 gas flow f was reduced to a final value of 308 CCM and the crystallinity was changed from 60% to 80%.

Next, 500800M% of SiH4 gas was introduced at a flow rate of 250 SCCM with a flow rate ratio of 10 to B2H6 gas f:5iIf4 gas, the pressure in the reaction vessel was set to f I Torr, and high frequency power of %400 W was applied to 151 krn. μe-8i: Charge generation consisting of H thin layer/! Please form f.

Finally, a surface layer consisting of 0.17 a-8 IC: H thin 71 was formed.

When the surface of the photoreceptor thus formed is positively charged at about 500V and exposed to white light, the light is absorbed by the charge generation layer and carriers of electron-hole pairs are generated.In this test example, In this test, a large number of carriers were generated, the carrier had a long life, and good running performance was obtained.As a result, clear and high-quality images were obtained.In addition, the photoreceptor manufactured in this test example When repeatedly charged, the reproducibility and stability of the transferred image are extremely good, and furthermore, it has corona resistance.

It has been demonstrated that it has excellent durability such as moisture resistance and abrasion resistance.

The photoreceptor manufactured in this manner has high sensitivity even to long wavelength light of 780 to 790 nm, which is the oscillation wavelength of a semiconductor laser. When this photoconductor was installed in a semiconductor laser printer and an image was formed using the Carlson process, the exposure amount on the photoconductor surface was 25 ergcrn.
Make sure you can't get clear, high-resolution images even if you are.

Test Example 2 An electrophotographic photoreceptor was manufactured in the same manner as Test Example 1, except that the charge generation layer was composed of μc-Sl:).

The charge generation layer is made of 5IH4 gas at 30 SCCM, H2
This was obtained by introducing gas at a flow rate of k 600 SCCM, setting the pressure inside the reaction vessel to 1.2 Torr, and applying 1.2 kWO high frequency power.

This photoreceptor? When an image was formed using the same method as in Test Example 1, a clear and high quality image was obtained.

Test Example 3 A-8iC:H, one of the thin films constituting the entire charge retention layer
An electrophotographic photoreceptor was produced in the same manner as in Test Example 1, except that a thin layer of a-8IN:H was entirely formed instead of the thin layer.

a-8IN: H thin layer is 5IH4 gas'Th 50
0 SCCM.

N2 gas at 120 SCCM, H2 gas at 250 S
It was introduced at a flow rate of CCM, and the pressure inside the reaction vessel was set to 1.2.
Torr, and was obtained by applying 400 W of high frequency power.

When an image was formed using this photoreceptor in the same manner as in Test Example 1, a clear and high quality image was obtained.

Test example 4 Charge retention/? An electrophotographic photoreceptor was manufactured in the same manner as in Test Example 1, except that the crystallinity of the μe-81:H thin layer constituting i was changed as shown in FIG.

When images were formed using these photoreceptors in the same manner as in Test Example 1, clear and high quality images were obtained.

Test Example 5 An electrophotographic photoreceptor was manufactured in the same manner as Test Example 2, except that the crystallinity of the μc-8i:H thin layer constituting the charge retention layer was changed as shown in FIG. .

When the entire image was formed using these photoreceptors in the same manner as in Test Example 1, a clear and high quality image was obtained.

Note that the types of thin layers constituting the charge retention layer and charge generation/& are not limited to two types as in the above test example, but three or more types of thin layers may be laminated. It is sufficient to form all the boundaries between thin layers with different values.

[Effects of the Invention] According to the present invention, since a superlattice structure formed by laminating thin layers with mutually different optical band gaps is used in the charge retention layer, carrier mobility is high and high efficiency is achieved. An electrophotographic photoreceptor with excellent resistance and charging characteristics can be obtained. In particular, the present invention has the advantage that by appropriately combining materials forming the thin layer, it is possible to obtain a photoreceptor having optimal photoconductive properties for light in any wavelength band.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an electrophotographic photoreceptor according to an embodiment of the present invention, FIG. 2 is a diagram showing an apparatus for manufacturing an electrophotographic photoreceptor according to an embodiment of the invention, and FIG. FIG. 3 is a diagram showing changes in the crystallinity of a thin film. DESCRIPTION OF SYMBOLS 1... Conductive support, 2... Barrier layer, 3... Photoconductive layer, 4... Surface layer, 5... Charge retention layer, 6...
Charge generation layer. (a) (C) (e) Layer 4 thickness (b) Layer 1 (d) Layer thickness (f) 3 Figure

Claims (11)

[Claims] (1) In an electrophotographic photoreceptor having a conductive support and a photoconductive layer, the photoconductive layer is composed of a charge generation layer and a charge retention layer, and the charge generation layer is composed of amorphous silicon and microcrystalline silicon. The charge retention layer contains at least one selected from carbon, oxygen, and nitrogen.
It is constructed by alternately laminating amorphous silicon thin films containing seed elements and microcrystalline silicon thin films, and the crystallinity of the microcrystalline silicon thin films changes from film to film in the layer thickness direction. Characteristic electrophotographic photoreceptor. (2) The electrophotographic photoreceptor according to claim 1, wherein the thin film has a thickness of 30 to 200 Å. (3) The electrophotographic image according to claim 1 or 2, wherein the photoconductive layer contains at least one element selected from elements belonging to Group III and Group V of the periodic table. Photoreceptor. (4) The electrophotographic photosensitive material according to any one of claims 1 to 3, wherein the charge generation layer contains at least one element selected from carbon, oxygen, and nitrogen. body. (5) The electrophotographic photoreceptor according to any one of claims 1 to 4, wherein the crystallinity of the charge generation layer changes in the layer thickness direction. (6) Any one of claims 1 to 5, wherein the microcrystalline silicon thin film constituting the charge retention layer contains at least one selected from carbon, oxygen, and nitrogen. The electrophotographic photoreceptor described in . (7) The concentration of the element contained in the amorphous silicon thin film constituting the charge retention layer varies from film to film in the layer thickness direction. The electrophotographic photoreceptor according to any one of the items. (8) A patent claim characterized in that a barrier layer made of an amorphous material or a semiconductor material in which at least a portion thereof is microcrystalline is formed between the conductive support and the photoconductive layer. The electrophotographic photoreceptor according to item 1. (9) The electrophotographic photoreceptor according to claim 8, wherein the barrier layer contains at least one element selected from elements belonging to Group III and Group V of the periodic table. . (10) The electrophotographic photoreceptor according to claim 8 or 9, wherein the barrier layer contains at least one element selected from carbon, oxygen, and nitrogen. (11) The electrophotographic photoreceptor according to claim 1, wherein a surface layer is formed on the photoconductive layer.