JPS63165858A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To enhance various characteristics including photosensitivity characteristics by constituting a photoconductive layer of an electric charge retaining layer and a charge generating layer at least one part of each layer having superlattice structure. CONSTITUTION:The photoconductive layer 3 of a photosensitive body is composed of both layers of the charge retaining layer 5 and the charge generating layer 6, and the layer 5 has the superlattice structure obtained by alternately laminating thin films of microcrystalline silicon differing in crystal form from each other and containing at least one of C, O, and N, and the layer 6 has the superlattice structure formed by alternately laminating thin films of amorphous silicon and thin films of microcrystalline silicon containing at least one of C, O, and N, thus permitting carrier transfer speed in the layer 3 to be enhanced, the service lives of the carriers to be extended by the superlattice effect of the superlattice structures, chargeability to be enhanced, nevertheless, resistance to be elevated, and adhesion to a substrate to be strengthened by forming 2 kinds of superlattice structures made of the necessary thin silicon films, and consequently, the photosensitive body to be enhanced in all the characteristics of chargeability, dark decay resistance, photosensitivity, and resistance to environmental conditions.

Description

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

[Prior art] Hydrogen (H)-containing analymphous silicon (hereinafter referred to as a)
-Sl:H) has recently attracted attention as a photoelectric conversion material, and has been applied not only to solar cells, thin film transistors, and image sensors, but also as photoreceptors in electrophotographic processes.

Conventionally, CdS, ZnO, Ss, or 5e-T was used as the material constituting the original conductive layer of the secondary photographic element.
or inorganic materials such as poly-7-N-vinylcarbasol (pvcz) or trinitrofluorenone (T
Organic materials such as NF) were used. However, compared to these inorganic or organic materials, a-81:H does not require recovery treatment because it is a non-polluting substance, has high spectral sensitivity in the visible light region, and has a high surface hardness. It has advantages such as excellent abrasion resistance and impact resistance. For this reason, a-81:H is attracting attention as a photoreceptor for electrophotographic processes.

This a-81:H is being studied as a photoreceptor based on the Carlson method, but in this case, the photoreceptor is required to have high resistance and photosensitivity. However, it is difficult to satisfy both of these characteristics with a single photoreceptor, so a barrier layer is provided between the photoconductive layer and the conductive support, and a surface charge retention layer is provided on the photoconductive layer. These requirements are met by creating a multilayer structure.

[Problems to be Solved by the Invention] By the way, a-8l:H is usually formed by a glow discharge decomposition method using a silane gas, but at this time, hydrogen is removed in the a”81H abdomen. The atmospheric and optical characteristics of the stain vary greatly depending on the difference in the amount of hydrogen.
As the amount of hydrogen that enters the -81: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. Therefore, it is difficult to use it, for example, in a radar beam link equipped with a semiconductor radar. Furthermore, when the hydrogen content in the *-81:H film increases, hydrogen having bond structures such as (5IH2) and 5IH2 may occupy most of the area in the film, depending on the film forming conditions.

In this case, the number of pores and silicon dangling gates increases, which deteriorates the photoconductive properties and makes the material unusable as an electrophotographic photoreceptor. Conversely, as the amount of hydrogen incorporated into a-81:H decreases, the optical bandgap becomes smaller and its resistance decreases, but the photosensitivity to longer wavelength light increases. However, when the hydrogen content is low, there is less hydrogen to combine with and reduce the silicon dangling glands. For this reason, the mobility of the generated carriers is reduced, the life span is shortened, and the photoconductive properties are deteriorated, making it difficult to use as an electrophotographic photoreceptor.

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

This invention was made in view of the above circumstances, and has excellent charging ability, similar residual potential, high sensitivity over a wide wavelength range up to the near infrared region, and excellent adhesion to the substrate. The purpose of the present invention is to provide an electrophotographic photoreceptor having good properties and excellent environmental resistance.

[Structure of the Invention (Means for Determining Problem t'') As a result of various studies, the present inventors have discovered that the photoconductive layer of an electrophotographic photoreceptor is composed of a charge retention layer and a charge generation layer,
Among them, the charge generation layer is formed by laminating a plurality of predetermined microcrystalline silicon films, that is, has a superlattice structure, and the charge retention layer is formed by laminating a predetermined amorphous silicon film and a microcrystalline silicon film, that is, having a superlattice structure. The present inventors have discovered that the above object can be achieved by configuring the present invention, and have completed the present invention.

That is, the electrophotographic photoreceptor of the present invention is an electrophotographic photoreceptor having a conductive support and a photoconductive layer, wherein the photoconductive layer has a charge generation layer and a charge retention layer, and the charge generation layer At least a part of the charge retention layer is composed of a plurality of microcrystalline silicon S containing at least 1 flll of an element selected from carbon, oxygen, and nitrogen, and having different crystallinity, all of which are alternately stacked, and at least a part of the charge retention layer The first part is characterized by being configured by alternately laminating amorphous silicon films and microcrystalline silicon films containing at least two or more elements selected from carbon, oxygen, and nitrogen. The difference in crystallinity between microcrystalline silicon films is preferably 5 to 30%, and 10 to 2%.
0% is highly preferable.

The microcrystalline silicon (μC-81) used in the present invention is thought to be formed in a mixed layer of microcrystalline silicon and amorphous silicon with a grain size of several tens of Angstroms, It has the following physical properties.First, X-ray diffraction measurements show a crystal diffraction pattern in which 20 is around 28 to 28.5 degrees, and it is an amorphous a-81 with only a halo. It is clearly distinguished from μc-8.
The resistance to the dark resistance of i can be adjusted to 10''Ω·m or more, and it can be clearly distinguished from 4-licrystalline silicon, which has a dark resistance of 100·1.

Optical pantoy + 2 of the μc-8i used in the present invention
7'(Eg") is, for example, 1.55 eV
h (D is desirable. However, it can be set arbitrarily within a certain range. In order to obtain the desired ILrEg', it is preferable to add the required amount of hydrogen to each and use it as μc-Si:H. , the dangling bonds of silicon are compensated, and the dark resistance and bright resistance are balanced.
Original conductive properties are improved.

Note that the actual μC-8L film often takes on a weak P-type or N-type depending on specific factors such as manufacturing conditions (it is particularly susceptible to becoming N-type).Therefore, in order to form a superlattice structure, To make it necessary El.

It is desirable to lightly dope impurities having opposite conductivity types to cancel out the P type or N type.

(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, the mobility of carriers in the photoconductive layer is large.
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 same figure, a conductive support l
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.

Further, the surface layer 4 is formed on the charge generation layer 6.

Note that both the charge retention layer 5 and the charge generation layer 6 have a superlattice structure.

2 to 4 show cross-sectional structures of electrophotographic photoreceptors according to other embodiments of the present invention. In the photoreceptor shown in FIG. 2, a part of the charge generation layer has a superlattice structure. In the photoconductor shown in FIG. 3, a part of the charge retention layer has a superlattice structure, and in the photoconductor shown in FIG. 4, a part of each of the charge generation layer and the charge retention layer has a superlattice structure. are doing.

Below, regarding the structure of the electrophotographic photoreceptor shown in Fig. fg1,
I will explain in detail.

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

The barrier layer 2 may be formed using μC-81 or a-81:Ht-, or may be formed using a-BN:H (amorphous boron to which nitrogen and hydrogen are added). Furthermore, an insulating film may be used. For example, μc-8t:H and a-
A high-resistance insulating barrier layer can be formed by containing 1 mm or more of an element selected from carbon C1 nitrogen N and oxygen O in 81:H. The thickness of barrier layer 2 is 10
0x to 10 μm is preferred.

The barrier layer 2 is formed in order to suppress the flow of charges between the conductive support 1 and the charge generation layer 5, thereby increasing the charge retention function of the surface of the photoreceptor and increasing the charging ability of the photoreceptor. It is something. Therefore, when a Carlson type photoreceptor is constructed using a semiconductor layer as a barrier layer, the barrier layer 2 is made to be P type or N type in order not to reduce the ability to retain charges charged on the surface. That is, when the surface of the photoreceptor is positively charged, the barrier layer 2t-P type is used to prevent electrons that neutralize the surface charge from being injected into the charge generation layer.

On the other hand, when the surface is negatively charged, the barrier layer 2 is of N type,
This prevents holes that neutralize surface charges from being injected into the charge generation layer. Since carriers generated in the charge generation layer 6 due to the incidence of the carrier Fi light injected from the barrier layer 2 become noise, preventing carrier injection as described above improves the sensitivity. In addition, μc −81
:H+a-8i: In order to make H the P type, it is possible to dope it with elements belonging to Group Ⅰ of the periodic table, such as boron B, aluminum AL, fium Ga, indium In, and thallium Tt. preferable. Also, μ
In order to make c-81:H or a-8t:Ht-N type, elements belonging to Group V of the periodic table, such as nitrogen, phosphorus P, arsenic A1, antimony Sb, and bismuth B1, are doped. It is preferable.

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, and the other carriers travel within the charge retention layer 5 and become conductive. The sexual support 1 is reached.

The charge retention layer 5 and the charge generation layer 6 are constructed by alternately laminating thin layers 11 and 12 made of μa-81 or 1-8L, as shown in the enlarged cross section of FIG. ing. The thin layers 11.12 have different optical bandgaps and each have a thickness in the range 30-200X.

FIG. 6 is an energy band diagram of a superlattice structure in which the horizontal axis represents the thickness direction and the vertical axis represents the optical band gap. 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 barrier thin layer is extremely thin, carriers pass through the barrier and travel through the superlattice structure due to carrier tunneling in the thin layer. In addition, in such a superlattice structure,
The number of carriers generated by the original injection is large, so 1
High light sensitivity.

Note that by changing the bandgap and layer thickness of the thin layer of the superlattice structure, the apparent bandgap of the layer having the heterojunction superlattice structure can be freely adjusted.

Charge retention layer 5 and charge generation layer 6t - a-fl constituting
The hydrogen content in it:u and μc-81:H is preferably 0.01 to 30 atoms, more preferably 1 to 25 atoms. Such a hydrogen content compensates for silicon dangling, brings the dark resistance and bright resistance into balance, and improves the photoconductive properties.

a-81:H! To form a film of fl by the glow discharge decomposition method, silane gases such as 81) 14 and 812M5 are introduced into the reaction chamber as raw materials, and Hl- is added into the thin layer by glow discharge using high frequency. I can do it. If necessary, hydrogen or helium gas can be used as a carrier gas for the silanes. On the other hand, SiF4
Silicon halides such as gas and gict4 gas can be used as the source gas. Furthermore, by reacting with a mixed gas of a silane gas and a silicon halide gas, a *-81:Ht- film containing Hi gold can be similarly formed. Note that these thin films can be formed not only by the glow discharge decomposition method but also by a physical method such as sputtering.

Similarly to a-81:H, the μc-81 layer can also be formed as a silane gas tM film by the high-frequency glow discharge decomposition method. In this case, the temperature of the support is set to a-81
:Ht-formation, and the high frequency power is also set higher than that of a 81 :H, μc
-81: Hl- becomes easier to form. Furthermore, by increasing the support temperature and high frequency power, the flow rate of source gas such as silane gas can be increased, and as a result, the film formation rate can be increased. In addition, 81 of the raw material gas
By using a gas obtained by diluting a high-order silane gas such as H4 and Si2H6 with hydrogen, μc-81:H can be formed with higher efficiency.

μc-81:H and a-St: In order to make H the P type, elements belonging to Group 1 of the periodic table, such as boron B, aluminum AL, gallium Qa, indium I
It is preferable to dope with n, thallium Tt, etc., and in order to make fie-Si:H and a-81:H n-type, doping with elements belonging to group Ⅰ of the periodic table, such as nitrogen N, It is preferable to dope with /P, arsenic AM, antimony Sb, bismuth B1, etc. This doping with p-type impurities or n-type impurities prevents charges from moving from the support side to the photoconductive layer. On the other hand, in μc -81:H and a -Sl:H, carbon C1
By containing at least one element selected from nitrogen (N) and oxygen (0), high resistance can be achieved and the surface charge retention ability can be increased. The content of these elements is 5
~40 atoms, preferably 10-30 atoms.

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

Since the charge generation layer 60μe-81:H and the like has a relatively large refractive index of 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 generation layer decreases, resulting in increased light loss. For this reason, it is preferable to provide the surface layer 4 to completely prevent reflection. Moreover, by providing the surface layer 4,
Charge generation layer 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. surface,! 11t- As a material for forming.

a-SIN:H, a-810:H, and a-SI
There are inorganic compounds such as C:H and organic materials such as polyvinyl chloride and polyamide.

When the surface of the electrophotographic photoreceptor constructed in this way is charged with a positive voltage of about 500 V by corona discharge, a potential barrier is formed as shown in FIG. When the element (hv) is incident on this photoreceptor, carriers of electrons and holes are generated in the superlattice structure of the charge generation layer 6. The electrons in the electron band 4 are accelerated toward the surface layer 49m by the electric field in the photoreceptor, and the holes are accelerated toward the conductive support 1 (ill). The number of carriers generated at the boundaries between different thin layers is much larger than the number of carriers generated in the bulk.Therefore, in this superlattice structure, there is a high photosensitivity and potential well layer. In this case, due to quantum effects, the carrier lifetime is 5 times shorter than in the case of a single layer without a superlattice structure.
It is 10 to 10 times longer. Furthermore, in a superlattice structure, a periodic barrier layer is formed due to the discontinuity of the Pandora, but carriers easily pass through the bias layer due to the tunnel effect, so the effective mobility of carriers is The carrier has excellent runnability.

Similarly, in the case of the charge retention layer 5, due to quantum effects, the lifetime of carriers in the potential well layer is 5 to 10 times longer than in the case of a single layer without a superlattice structure.

In addition, in a superlattice structure, a periodic barrier layer is formed due to the discontinuity of the band gap, but carriers easily pass through the bias layer due to the tunnel effect, so the effective mobility of carriers is The mobility is equivalent to that in bulk, and carrier mobility is excellent. As described above, the superlattice structure in which thin layers with different optical band gaps are laminated can provide high photoconductivity and provide clearer images than conventional photoreceptors.

Referring to FIG. 6, an apparatus and a manufacturing method for manufacturing the electrophotographic photoreceptor of the above embodiment by a glow discharge method will be described below. In the same figure, gas? Npe 21,22m23.
24, for example, S i H4aB2H6a B2
- Contains raw material gas such as CH4. The gas in these gas gompes is supplied to a mixer 28 via a pipe 27 and a pipe 26 for adjusting the flow rate. A pressure gauge 25 is installed in each gas, and by monitoring the pressure gauge 25t and adjusting the pulp 26t, the flow rate and mixing ratio of each M gas to be supplied to the mixer 28 can be adjusted. The gas mixed in the mixer 28 is transferred to the reaction container 2
9. A rotating shaft 30 is attached to the bottom 31 of the reaction vessel 29 so as to be rotatable in a 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 part 3 with its axial center aligned with the axial center of the rotating shaft 30. A drum base 34 of a photoreceptor is placed on a support base 32 with its axial center aligned with the axial center of the rotating shaft 30, and a heater 35 for heating the drum base is disposed inside the drum base 34. has been done. A high-frequency electric current @36 is connected between the electrode 33 and the drum base 34, and the zero-rotation shaft 30, through which high-frequency current is supplied between the electrode 33 and the drum base 34, is driven by a motor 38. The pressure within one reaction vessel 29 that is driven to rotate is monitored by a pressure gauge 37, and the reaction vessel 29 is connected to a suitable evacuation means such as a vacuum pump via a dirt pulp 38f. .

When manufacturing a photoreceptor using the above-mentioned manufacturing apparatus, after installing the drum base 34f in the reaction container 29, the dirt pulp 39 is opened and the inside of the reaction container 29 is heated to about 0.1 Torr.
0 then evacuate below the pressure of ? Empe 21, 22.2
From 3.24 onwards, required reaction gases are mixed at a predetermined mixing ratio and introduced into the reaction vessel 29. In this case, the reaction vessel 29
The gas flow rate introduced into the reaction vessel 29 is such that the pressure inside the reaction vessel 29 is 0.1.
~1. Set it to OTorr 0 then
The motor 38t is activated to rotate the drum base 34t, the heater 35 heats the citrus base 34t to a constant temperature, and the high frequency electric current is supplied between the stain electrode 33 and the drum base 34 using a high frequency electric current @36. A glow discharge is formed between the two. As a result, a
-81: H is deposited. In addition, K N, O,
By using NH, lN02sN2@CH4, C2H410□ gas, etc., these elements can be converted into a-8l :H
It can be contained inside.

As described above, since the electrophotographic photoreceptor according to the present invention can be manufactured using a closed system manufacturing apparatus,
Safe for humans.

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 An aluminum drum base with a diameter of 80 mm and a width of 350 points, which has been subjected to acid treatment, alkali treatment, and sand f-last treatment to prevent interference as necessary, was installed in a reaction vessel and one reaction was carried out. The vessel was evacuated to a vacuum of approximately 10-5 torr.

While heating the drum base to 250°C and rotating it at 10 rpm, 5fiH4 gas 1500 SCCM, B2H
6f gas and the flow rate ratio to H4 gas is 10-5, CH4
Gas was introduced into the reaction vessel at a flow rate of 1008 CCM, and the pressure inside the reaction vessel was adjusted to 1 Torr. And 13
．． Plasma was generated by applying high frequency power of 56 MHz to form a p-type s-81C:H barrier layer on the drum substrate.

Next, the discharge is temporarily stopped, and the NHs gas flow rate is t-1208.
0CM was introduced, the reaction pressure was adjusted to 1.2 Torr, and 500
Applying high frequency power of W, 1001 a -81N:
Then, 8% H4 gas was added to 5008C to form a thin H layer.
CM, H2 gas was introduced into the reaction vessel at a flow rate of 500 SCCM, and a high frequency power of 600 W was applied to give a 100X
A thin layer of .mu.c-81:H was formed.

Repeat these operations to create 600 layers of a-8IN:
The H thin layer and 600 μc -81:H thin layers were alternately laminated to form a charge retention layer with a heterojunction superlattice structure f:12.

Input 1 reaction pressure? : Adjust to 1.2 Torr.
o o w” high frequency power is applied, 100X μc
-SiC:H thin yx<m crystallinity 60%) T-type g
T, Ri. The flow rate of FK and CH4ff was increased by 12SCCMK, and 1001Oμc-81C:H thin layer (N crystallinity 75%) was added.
) was formed. By repeating this operation, 250 layers of μc-81C:H thin layer and 250 μc layers with different degrees of grain setting were obtained.
c-81C:)i were alternately stacked to form a 5 μm charge generation layer having a heterojunction superlattice structure.

Next, a 0.5IB a-SiC:1 layer was formed as a surface layer.

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

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 wavelength discovered by semiconductor radar. When this photoreceptor was installed in a semiconductor radar printer and multiple images were formed using the Carlson process, clear, high-resolution images could be obtained even when the exposure amount on the photoreceptor surface was 25·rga+2. .

-SIN: 100X a in place of H thin layer -SiC:
An electrophotographic photoreceptor was produced in the same manner as in Test Example 1 except that a thin H layer was formed.

Note that the a-81C:H thin layer is formed by CH4 gas flow tt75
Set to SCCM, the reaction vessel internal pressure t' 1.2 To
It was obtained by adjusting to rr and applying high frequency power of sow.

When this photoreceptor was repeatedly charged, the transferred image had high reproducibility and stability, and had excellent durability such as corona resistance, moisture resistance, and abrasion resistance.

In the above test example, the thickness of the charge generation layer was 5.5 mm.
However, the thickness is not limited to this, and even if it is set to 1 or 3 μm, it can be practically used as a photoreceptor.

The types of thin layers in the case are not limited to two types as in the above test example, but three or more types of thin layers may be laminated.

In short, it is sufficient to form a boundary between thin layers having different optical band gaps.

[Effects of the Invention] According to the present invention, a superlattice structure in which the optical band gear lugs are formed by laminating different thin layers is used in part or all of the photoconductive layer, so that light from visible light to near-infrared light is emitted. It is possible to obtain an electrophotographic photoreceptor that is highly sensitive over a wide wavelength range of external light, has high carrier mobility, has high resistance, and has excellent charging characteristics. In particular, the present invention has the advantage that by appropriately combining famous materials forming the thin layer, it is possible to obtain a photoreceptor having optimal photoconductive properties for 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, FIGS. 2 to 4 are sectional views showing an electrophotographic photoreceptor according to another embodiment, and FIG. FIG. 6 is a diagram showing the energy band of the superlattice structure, FIG. 7 is a diagram showing an apparatus for manufacturing an electrophotographic photoreceptor according to an embodiment of the present invention, and FIG. The figure is a schematic diagram showing the energy gap of a photoreceptor. Applicant's agent Patent attorney Takehiko Suzue Figure 1
Figure 2 Figure 3 Figure 4 Figure 5 Figure 1, Indication of the case Japanese Patent Application No. 61-315569 2, Name of the invention Electrophotographic photoreceptor 3, Person making the amendment Relationship to the case Patent applicant (307) Stock Company: Toshiba (and 1 other person) 4. Agent: UBE Building 7, 3-7-2 Kasumigaseki, Chiyoda-ku, Tokyo.
Contents of the amendment (1) “In addition,” on page 8, lines 8 to 13 of the specification.
·····desirable. ” to be deleted. (2) r 25 erg on page 23, line 12 of the specification
Correct dJ to r 25 erg/d J.

Claims (7)

[Claims] (1) In an electrophotographic photoreceptor having a conductive support and a photoconductive layer, the photoconductive layer has a charge generation layer and a charge retention layer, and at least a portion of the charge generation layer contains carbon, oxygen, A plurality of microcrystalline silicon films containing at least one element selected from carbon and nitrogen and having different degrees of crystallization are alternately stacked, and at least a part of the charge retention layer contains carbon, oxygen and An electrophotographic photoreceptor characterized in that it is constructed by alternately laminating amorphous silicon films and microcrystalline silicon films containing at least one element selected from nitrogen. (2) The electrophotographic photoreceptor according to claim 1, wherein the microcrystalline silicon film and the amorphous silicon film have a thickness of 30 to 200 Å. (3) The electrophotographic photosensitive material according to claim 1 or 2, wherein the photoconductive layer contains at least one element selected from elements belonging to Group III or V of the periodic table. body. (4) A barrier layer made of an amorphous material or a semiconductor material at least partially microcrystalline is provided between the conductive support and the photoconductive layer.
The electrophotographic photoreceptor described in . (5) The electrophotographic photoreceptor according to claim 4, wherein the barrier layer contains at least one element selected from elements belonging to Group III or Group V of the periodic table. (6) The electrophotographic photoreceptor according to claim 4, wherein the barrier layer contains at least one element selected from the group consisting of carbon, oxygen, and nitrogen. (7) The electrophotographic photoreceptor according to claim 1, further comprising a surface layer on the photoconductive layer.