JPS62115457A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain an electrophotographic sensitive body having superior electrostatic chargeability, low residual potential, high sensitivity in a wide wavelength region and superior environmental resistance by forming a laminate consisting of amorphous silicon and microcrystalline silicon as a photoconductive layer. CONSTITUTION:A muC-Si layer 104 and an a-Si layer 106 are laminated on an electrically conductive Al support 101 to form a photoconductive layer 103. The layers 104, 106 contain at least one kind of atom selected among the group III and IV atoms in the periodic table and at least one among C, O and N. The atoms in the layers have ununiform concn. distributions in the thickness direction so that the concns. are made lower on the support side. When light close to visible light is irradiated on the resulting electrophotographic sensitive body, the a-Si layer 106 absorbs most of the light and the muC-Si layer 104 absorbs the remaining light unabsorbed in the layer 106.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This defense relates to an electrophotographic photoreceptor having excellent charging characteristics, photosensitivity characteristics, environmental resistance, etc.

[Prior art and its problems] Conventionally, as materials for forming the photoconductive layer of an electrophotographic photoreceptor, inorganic materials such as CdS, zno, Se, 5e-7e, or amorphous silicon, or poly-N-vinylcarbazole (PVCz) have been used. or trinitrofluorene<T
However, these conventional photoconductive materials have various problems in terms of photoconductive properties or manufacturing, and the characteristics of the photoreceptor system may be sacrificed to some extent. These materials are used differently depending on the purpose of use.

For example, Se and CdS are materials that are harmful to the human body, and special consideration must be given to safety measures when manufacturing them. Therefore, there are problems in that the manufacturing equipment becomes complicated and the manufacturing cost is high, and in particular, Se needs to be recovered, which adds to the recovery cost. Also,
In the Se or 5e-Te system, the crystallization temperature is 65°C
Therefore, during repeated copying, problems with the photoconductive properties arise due to residual snow, etc., and therefore, the service life is short and practicality is low.

Furthermore, ZnO is susceptible to oxidation-reduction and is significantly affected by the environmental atmosphere, resulting in a problem of low reliability in use.

Furthermore, organic photoconductive materials such as PVCz and TNF are suspected to be carcinogens and present human health concerns, and organic materials have low thermal stability and abrasion resistance. , has the disadvantage of short lifespan.

On the other hand, amorphous silicon (hereinafter abbreviated as a-3i)
has recently attracted attention as a photoconductive conversion material, and is being actively applied to solar cells, thin film transistors, and image sensors. As part of this application of a-3i, attempts have been made to use a-8i as a photoconductive material for electrophotographic photoreceptors, and photoreceptors using a-8i are collected because they are non-polluting materials. No processing required;
Compared to other materials, it has advantages such as high spectral sensitivity in the visible light region, high surface hardness, and poor abrasion resistance and impact resistance.

This a-8i is being studied as a photoreceptor based on the Carlson method, but in this case, the photoreceptor characteristics are required to be high resistance and photosensitivity. Since it is difficult to satisfy the requirements with a photoreceptor, we created an 8i layer type structure in which a blocking layer is provided between the photoconductive N layer and the conductive support, and a surface charge retention layer is provided on the photoconductive layer. , satisfies these requirements.

By the way, a-8i is usually formed by a glow discharge decomposition method using silane gas, but at this time, a-8i is
Hydrogen is incorporated into 3i, and the electrical and optical properties vary greatly due to the difference in the hydrogen port (i.e., a-3i
As more hydrogen enters the film, the optical bandgap becomes larger and the resistance of a-8i increases, but as a result, the photosensitivity to long wavelength light decreases. , it is difficult to use it in a laser beam blink equipped with a semiconductor laser. Also, a-3i
If the hydrogen content in the film is high, depending on the film forming conditions,
Those having bonding structures such as (SiH2)rL and SiH2 may occupy most of the area in the film. In this case, voids increase and silicon dangling bonds increase, resulting in deterioration of photoconductive properties and rendering the material unusable as an electrophotographic photoreceptor. Conversely, as the amount of hydrogen entering a-3i decreases, the optical bandgap decreases,
Its resistance decreases, but its photosensitivity to long wavelength light increases. However, when the hydrogen content is low, there is less hydrogen to combine with and reduce silicon dangling bonds. 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 addition, as a technique to increase the sensitivity to long wavelength light, there is a method of mixing silane-based gas and germane GeH+ and decomposing it with glow lightning to produce a film with a narrow optical band gap. Since the gas and GeH4 have different optimum substrate temperatures, the produced film has many structural defects and cannot obtain good photoconductive properties. Further, since GeH+ gas becomes a toxic gas when oxidized, waste gas treatment is also complicated. Therefore, such technology is not practical.

The present invention was made in view of the above circumstances, and provides an electrophotographic photoreceptor that has excellent charging ability, low residual potential, high sensitivity over a wide wavelength range, and excellent environmental resistance. The purpose is to

[Means for Solving the Problems] An electrophotographic photoreceptor according to the present invention includes an electrically conductive support and a photoconductive layer formed on the electrically conductive support. The light guiding N layer includes an amorphous silicon layer and a microcrystalline silicon layer formed between the amorphous silicon layer and a conductive support, and the amorphous silicon layer and the microcrystalline silicon layer have a dominant conductivity type. and at least one kind of atoms selected from carbon, nitrogen, and oxygen form a nonuniform S degree distribution in the layer thickness direction.

The present inventor has developed an electrophotographic photoreceptor according to the present invention in order to overcome the drawbacks of the prior art described above and to develop an electrophotographic photoreceptor that has both excellent photoconductive properties (single-child photographic properties) and environmental resistance. As a result of various experimental studies, they found that this objective could be achieved by making part or all of the light guiding N layer consist of microcrystalline as a seed, or by making it a laminate of amorphous silicon and microcrystalline silicon. This invention was completed after coming up with the idea that this could be done.

This invention will be explained in detail below.

This invention includes amorphous silicon (hereinafter referred to as a-3i) or microcrystalline silicon (hereinafter referred to as μC=
Si) is used.

μC-8i is a-
8i and polycrystalline silicon (polycrystalline silicon)
clearly distinguished from That is, in X-ray diffraction measurement, since a-3i is amorphous, only a halo appears;
Although no diffraction pattern can be observed, μC-8i shows a crystal diffraction pattern with a 2θ of around 27 to 28.5°.

In addition, polycrystalline silicon has a dark resistance of 10”Ω.
ctrt, whereas μC-8i is 109Ω・ct
It has a dark resistance of rr or more. This μC-8i is formed by agglomeration of microcrystals having a grain size of approximately several tens of angstroms or more.

Similar to a-3i, such a μC-8i layer can be manufactured by depositing μC-SR on a conductive support using silane gas as a raw material by a high frequency glow discharge decomposition method. In this case, the temperature of the support is set to a-
higher than when forming 8i (setting, high frequency power is also a
If it is set higher than -3i, μC-8i will be more likely 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, raw material gas SiH4 and Si2H6
By using a gas obtained by diluting a high-order silane gas such as silane gas with hydrogen, μc-sr can be formed with even higher efficiency.

FIG. 1 is a diagram showing an apparatus for manufacturing an electrophotographic photoreceptor according to the present invention. For example, the gas cylinders 1 and 2°3.4 contain SiH+ and B2 H6, respectively.

Source gases such as H2 and CH4 are contained. The gas in these gas cylinders 1.2, 3.4 is supplied to a mixer 8 via a pulp 6 for flow adjustment and piping 7. Each cylinder is equipped with a pressure gauge 5, and by monitoring the pressure gauge 5 and adjusting the valve 6, the flow rate and mixing ratio of each raw material gas supplied to the mixer 8 can be adjusted. can. The gases mixed in the mixer 8 are supplied to a reaction vessel 9. A rotating shaft 10 is attached to the bottom 11 of the reaction vessel 9 so as to be rotatable around the vertical direction, and a disk-shaped support 12 is attached to the upper end of the rotating shaft 10 with its surface perpendicular to the rotating shaft 10. It has been fixed. Inside the reaction vessel 9, a cylindrical electrode 13 is installed on the bottom 11 with its axial center aligned with the axial center of the rotating shaft 10.

A drum base 14 of a photoreceptor is placed on a support base 12 with its axial center aligned with the axial center of the rotating shaft 10, and a heater 15 for heating the drum base is arranged inside the drum base 14. It is set up. A high frequency power source 16 is connected between the electrode 13 and the drum base 14, so that a high frequency current is supplied between the electrode 13 and the drum base 14. The rotating shaft 10 is rotationally driven by a motor 18. The pressure inside the reaction vessel 9 is monitored by a pressure gauge 17, and the reaction vessel 9 is connected via a gate pulp 18 to an appropriate evacuation means such as a vacuum pump.

When manufacturing a photoreceptor using an apparatus configured as described above, after installing the drum base 14 in the reaction vessel 9, the gate valve 19 is opened to generate a pressure inside the reaction vessel 9 of approximately 0.1 Torr. ). Next, cylinder 1
, 2.3.4, the required reaction gases are mixed at a predetermined mixing ratio and introduced into the reaction vessel 9. In this case, reaction vessel 9
The gas flow rate introduced into the reaction vessel 9 is such that the pressure inside the reaction vessel 9 is 0.1.
Set it so that it is between 1 Torr and 1 Torr. Next, the motor 18
is activated to rotate the drum base 14, the heater 15 heats the drum base 14 to a constant temperature, and the high frequency power supply 16 supplies a high frequency current between the electrode 13 and the drum base 14 to create a glow between them. form a discharge.

As a result, μC-8i is deposited on the drum base 14. Note that N20. NH3, NO2, N2
.

By using CH4, C2H4,02 gas, etc.
These atoms can be included in μC-8i.

In this way, the electrophotographic photoreceptor according to the present invention has a conventional a
Similar to those using -8i, it can be manufactured using closed system manufacturing equipment, so it is safe for the human body. Furthermore, this electrophotographic photoreceptor has excellent heat resistance, moisture resistance, and abrasion resistance, so it has the advantage of having a long lifespan with little deterioration even after repeated use over a long period of time. Furthermore, since a long wavelength sensitizing gas such as QeH4 is not required, there is no need to provide waste gas treatment equipment, and industrial productivity is extremely high.

It is preferable that μC-8i contains 0.1 to 30 at % of hydrogen. As a result, the dark resistance and bright resistance become harmonious, and the photoconductive properties are improved. μc-
The optical energy gap Ea of s i is the optical energy gap Ea of a-8i (1,65 to 'I,
708 V) G, :tlt, T small. In other words, μ
The optical energy gap of C-8i changes depending on the grain size and crystallinity of UC-8i microcrystals, and as the grain size and crystallinity increase, the optical energy gap decreases, and crystalline silicon Optical energy gap 1.
approaches 1eV. By the way, μC-S+S and a-8i
i absorbs light with a larger energy than this optical energy gap, and transmits light with a smaller energy. Therefore, a-8i absorbs only visible light energy, but a
μC-3i has a smaller optical energy gap than -3i
can even absorb near-infrared light, which has a longer wavelength and lower energy than visible light. Therefore, μC-8i has high photosensitivity over a wide wavelength range.

μC-S + having such characteristics is suitable as a photoreceptor material for a laser printer using a semiconductor laser as a light source. When a-3i is used as a photoreceptor for a laser printer, the light wavelength of the semiconductor laser is 790 nm and a-8
Since i is longer than the wavelength range in which it is highly sensitive, the sensitivity of the photoreceptor becomes insufficient, and therefore it is necessary to apply a laser intensity to the photoreceptor that exceeds the ability of the semiconductor laser, which is a practical problem. On the other hand, when a photoreceptor is formed using μC-S+, its high sensitivity region extends to the near-infrared region, so it is possible to obtain a photoreceptor for semiconductor laser printers with extremely excellent photosensitivity characteristics. .

In order to further improve the photoconductive properties of μc-s i, which has such excellent photosensitivity characteristics, μ
It is preferable that c-si contains hydrogen.

Hydrogen doping to the μc-s r layer is performed, for example, by glow tIl electrolysis, 5it-I4 and 3i
Either a silane-based source gas such as 2Hs and a carrier gas such as hydrogen are introduced into the reaction vessel to cause glow discharge, or S
A mixed gas of a silicon halide such as iF4 and 5iCl+ and hydrogen gas may be used, or a mixed gas of a silane gas and a silicon halide may be used. Furthermore, the μC-SR layer can also be formed by a physical method such as sputtering instead of the glow discharge decomposition method. Note that the photoconductive layer containing μC-8i is
In terms of photoconductive properties, it is preferable to have a film thickness of 1 to 80 μm, and more preferably a film thickness of 5 to 50 μm.

Substantially the entire region of the photoconductive layer may be formed of μC-8i, or may be formed of a mixture or a laminate of a-8i and μC-8i. The charging ability is higher in the laminate, and the photosensitivity is higher in the long wavelength region of the infrared region, although it depends on the volume ratio, in the mixture, and in the visible light region, the two are almost the same.

Therefore, depending on the use of the photoreceptor, substantially all the regions may be made of μC-8i, or may be made of a mixture or a laminate.

Preferably, μC-8i is doped with at least one type of atom selected from nitrogen, N, carbon, and oxygen. Thereby, the dark resistance of μC-8i can be increased and the photoconductive properties can be improved.

These atoms precipitate at the grain boundaries of μC-8i and act as terminators for silicon dangling bonds,
It is thought that the density of states existing in the forbidden band between bands is reduced, thereby increasing the dark resistance.

Preferably, a blocking layer is provided between the conductive support and the photoconductive layer. This blocking layer suppresses the flow of charge between the conductive support and the photoconductive layer, thereby increasing the charge retention function on the surface of the photoconductive member and increasing the charging ability of the photoconductive member. . In the Carlson method, when the surface of the photoreceptor is positively charged, the blocking layer is made p-type in order to prevent electrons from being injected from the support side to the photoconductive layer. On the other hand, when the surface of the photoreceptor is negatively charged, the blocking layer is made n-type in order to prevent holes from being injected from the support side to the photoconductive layer. It is also possible to form an insulating film on the support as a blocking layer. The blocking layer may be formed using μC-8i or a-3
It is also possible to use i to construct a blocking layer.

In order to make μC-8i and a-8i p-type, they must be doped with atoms belonging to Group Ⅰ of the periodic table, such as boron B, aluminum AI, gallium Ga, indium (n, and thallium T1). is preferable, μC-8i
In order to make the layer n-type, atoms belonging to group Ⅰ of the periodic table, such as nitrogen N, phosphorus P, arsenic As, and antimony s, must be added.
It is preferable to dope with B, bismuth Bi, or the like.

This n-type impurity or doping with n-type impurities prevents charges from moving from the support side to the photoconductive layer.

Preferably, a surface layer is provided on top of the photoconductive layer.

Since μC-8i of the photoconductive layer has a relatively large refractive index of 3 to 4, light reflection easily occurs on the surface. When such light reflection occurs, the ratio of light absorbed by the photoconductive layer decreases, increasing optical loss. For this reason, it is preferable to provide a surface layer to prevent reflection. Also, by providing the surface layer, the photoconductive layer is protected from damage. Furthermore, by forming a surface layer, charging ability is improved,
The surface becomes more charged. Materials forming the surface layer include Si3N4, SiO2, 5iC1AI2
03, a-8iN; H, a-8iO: Hl and a-8
There are inorganic compounds such as iC;) and organic materials such as polyvinyl chloride and polyamide.

As described above, for photoconductive members applied to electrophotographic photoreceptors, a blocking layer is formed on a support, a light guide tS is formed on this blocking layer, and a surface layer is formed on this light guide 1i layer. The structure is not limited to one in which a layer is formed, but can also be constructed in a functionally separated form in which a charge transfer VJ layer (CTL) is formed on the support and a charge generation layer (CGL) is formed on the charge transfer layer. can. In this case, a blocking layer may be provided between the charge transfer layer and the support. The charge generation layer generates carriers upon irradiation with light. The charge generation layer is preferably made of .mu.C-8i or a-3i in part or in its entirety, and has a thickness of 0.1 to 10 .mu.m. The charge transfer layer is a layer that allows carriers generated in the charge generation layer to reach the support side with high efficiency, and therefore, the carriers need to have a long life, high mobility, and high transportability. The charge transport layer can be formed of a-8i. In order to increase the dark resistance and improve the charging ability, it is preferable to light-dope atoms belonging to either Group Ⅰ or Group V of the periodic table. In addition, in order to further improve the charging ability and to have the functions of both a charge transfer layer and a charge generation layer, one of C9N and O atoms was added.
More than one species may be included. If the charge transport layer is too thin or too thick, it will not function satisfactorily. Therefore, the thickness of the charge transport layer is 3 to 80 μm.
It is preferable that

By providing a blocking layer, even in a functionally separated type photoreceptor having a charge transfer layer and a charge generation layer, its charge retention function and charging ability can be improved. Note that whether the blocking layer is n-type or n-type is determined depending on its charging characteristics. This blocking layer may be formed of a-8i or μC-8
It may be formed by i.

The invention according to this application is characterized in that the photoconductive layer includes an amorphous silicon layer and a microcrystalline silicon layer formed between the amorphous silicon layer and a conductive support, The silicon layer is characterized in that atoms that control the conductivity type and at least one type of atoms selected from carbon, nitrogen, and oxygen form a non-uniform concentration distribution in the layer thickness direction.

[Example 2] Next, the structure of the layers of an electrophotographic photoreceptor embodying the present invention will be described with reference to Example 2.

In the electrophotographic photoreceptor shown in FIG. 2, a photoconductive layer 103 is laminated on a conductive support 101 made of aluminum. A uc-8i layer 104 and an a-8i layer 106 are stacked on the photoconductive layer 103.
The 6 and μc-8i layer 104 contains at least one type of atom selected from Groups ① and ② of the periodic table, and C
10, at least one N atom is contained. Furthermore, the concentration of these atoms has a non-uniform concentration distribution in the direction of the layer thickness, such that the layer becomes thinner on the support side.

According to the electrophotographic photoreceptor of the present invention, the photoconductive layer 103
, a UC-8i layer 104 and an A-3i layer 106 are stacked in this order from the conductive support 101 side. According to the configuration of such an electrophotographic photoreceptor, when the electrophotographic photoreceptor is irradiated with light near visible light, the a-8i layer 1
06, and the microcrystalline silylon μC-3i layer 104 absorbs the light that cannot be completely absorbed here. In addition, when light with a wavelength near infrared rays is irradiated, a-
The 3i layer 106 absorbs only a few tens of percent, and the rest is μ
C-8i layer 104 can absorb.

When only A-8i is used as a photoconductive layer, it has high sensitivity near visible light, but the photosensitivity drops rapidly to light with a wavelength near infrared rays, which is normally used in laser printers. There are disadvantages in that image defects such as fog, blur, fog, and unevenness in IIIf distribution of the image due to buffer stripes occur. However, according to the electrophotographic photoreceptor of the present application, as described above, since the μC-8i layer 104 is provided between the a-8i 106 and the support 101, it is possible to absorb light in a wide range of wavelengths. As a result, clear images can be obtained.

When the electrophotographic photoreceptor is charged, the a-8i layer 10
6 holds charges on its free surface side, and then when irradiated with light, the a-8i layer 106 and the μc-8i layer 10
Optical carriers are generated at 4 and 4. The generated optical carriers are instantaneously transported and neutralize the charges held on the free surface side of the a-8i layer 106. In this case, the photoconductive layer is μC-8
Since it contains the i-layer 104, charging ability is improved and high contrast can be obtained.

The a-3i layer 106 contains atoms that control the conductivity type and C
, O, and N atoms are contained, but the concentration distribution of this inclusion is formed non-uniformly in the layer pressure direction. in this case,
Peeling of layers or generation of cracks can be prevented, and furthermore, carrier trapping can be prevented, so blurring or blurring of images can be prevented. If the concentration distribution of the inclusions is constant in the layer pressure direction, if a layer with a relatively large optical bandgap width is formed in this layer, there will be a problem of poor adhesion between these 211 after film formation. There is. As a result, the adhesion between the two layers is poor and peeling or cracking occurs. Or, because the characteristics of the two layers are different, carriers may be trapped between these layers, causing the image to blur or run.

According to this invention, it is highly sensitive to light with wavelengths from visible light to near infrared rays, so it is highly sensitive to long wavelength light, and can be used as a photoreceptor for printers. , it is possible to provide a photoreceptor with excellent charging ability at a higher resolution and at a higher cost.

Next, embodiments of the invention will be described.

A Helmet drum (diameter 80 mm, length 350 mm) serving as a conductive substrate was degreased with trichlene, washed and dried, and then loaded into a reaction vessel. The surface of this drum is subjected to acid treatment, alkali treatment, or sandblasting treatment as necessary to prevent interference. Drum base 101
is heated and maintained at approximately 300°C. Then, S i H
B2 H6 gas with a flow rate ratio of 5 x 104 to 4 gases and 5% N2 gas were mixed and supplied to the reaction vessel.

After that, the inside of the reaction vessel was evacuated using a mechanical booster pump and a rotary pump, and the reaction pressure was reduced to 17 Or (i-
Adjusted to While the base 14 is rotated by the motor 18, high frequency power of 700 W (watts) is applied to the electrode to generate plasma between the electrode and the drum base (
(glow discharge) 4 years ago. 45 minutes after the start of film formation, N2
After 2 hours, the flow rate of N2 relative to the S i H4 gas flow rate was lowered to 5X10-7, and then 1
It took a while to form the film. After that, gradually reduce the flow rate of N2 and
The feed was stopped after 0 minutes. The film was formed in this state for 2 hours,
TLC-8i with a film thickness of 18 μm! 1104 was formed.

At the start of film formation of this μC-Si layer 104, the crystal powder diameter was 5
The crystal grain size at the end of film formation was 30 and the crystallinity was 60%.

Next, 3% N2 gas, a reaction pressure of 0.6 Torr, and 300 W of high frequency power were applied to the SiH + gas flow iron.
Discharge started. After 1 hour of film formation, the amount of N2 gas supplied was gradually increased until it reached 300% after 30 minutes, and film formation was completed. In this way, a 6 μm thick a-3i layer 106 was formed.

Comparative Example 1 In this comparative example, a photoreceptor made only of a-3i111 was formed. The layer structure of this comparative example consisted of a support 101, a blocking layer, a photoconductive layer, and a surface layer in this order. In this case, the blocking layer is N
2 to 50%, H2 gas to 100%, B2 H6 gas to 5%
Supplied at a flow rate of X10゛3, the reaction pressure was 056 Torr,
A high frequency power of 300 W was applied to form a film for 5 minutes. The photoconductive layer was prepared by supplying H2 gas at 100% and 82 H6 gas at a flow rate ratio of 10-6 to the Si H4 gas flow rate, applying a reaction pressure of 0.6 Torr, and 200 W of high-frequency power. , the film was formed for 3 hours. After forming the photoconductive layer, S i H
CH4 was supplied at a flow rate of 5 times the flow rate of 4 gases, the reaction pressure was 0.5 Torr, and 200 W of high frequency power was applied to generate a glow discharge, and a film was formed for 5 minutes to form a surface layer. did. In this case, the total film thickness was 25 μm.

A comparative experiment was conducted on the photoreceptors of Example 1 and Comparative Example 1 formed as described above. When a voltage of 6.5 KV (kilovolts) was applied to each photoreceptor, the surface potential of Example 1 was 550 V, and the retention rate for 15 seconds was 60%. on the other hand,
The surface potential of the comparative example was 400V, and the retention rate was 30%.

Furthermore, as shown in the graph of FIG. 3, the photosensitivity of each photoreceptor to wavelength was measured. In this Figure 3, the horizontal axis shows the wavelength of light (nm), and the vertical axis shows the sensitivity (Cm/erg).
We measured the sensitivity at multiple wavelengths. In this graph, the solid line indicates the measurement results of Example 1, and the broken line indicates the measurement results of Comparative Example 1. As is clear from this graph, according to this Example 1, good sensitivity could be obtained for light in the long wavelength region of about 700 to 800 nm.

Next, each photoreceptor was attached to a laser printer, an image was formed by the laser printer, and the images were compared. In this case, in Example 1, a clear image with high resolution and high contrast was obtained.

On the other hand, in the case of Comparative Example 1, image density unevenness caused by fogging or interference fringes occurred.

Example 2 In Example 1, the maximum flow ratio of N2 gas to the SiH4 gas flow chamber was varied to form a non-uniform concentration distribution in the layer thickness direction. The film was formed under the same conditions as in Example 1 in other respects.

The relationship between the layer thickness of the photoreceptor in this case and the flow rate ratio of N2 gas to the SiH+ gas flow rate is shown in FIGS. 4 to 12.

4 to 12, the horizontal axis shows the gas flow rate ratio, the vertical axis shows the layer thickness, the solid line shows the flow rate of a gas containing at least one of C10 and N atoms, and the broken line shows the periodic law table. It shows the flow rate of a gas containing at least one kind of atoms of Group Ⅰ or Group V of . In either case, the concentration of atoms contained in each gas is non-uniform in the thickness direction of the layer. In the case of this Example 2,
The same effects as in Example 1 could be obtained.

In this example, CH4 gas was used instead of N2 gas used in Example 2 to form an electrophotographic photoreceptor. In the case of Example 3 as well, the same effects as in Example 1 could be obtained.

[Effects of the Invention] According to the present invention, electrophotography has high resistance, excellent charging characteristics, high photosensitivity in the visible light and near-infrared light regions, is easy to manufacture, and has high practicality. A photoreceptor can be obtained.

[Brief explanation of drawings]

FIG. 1 is a diagram showing eight manufacturing steps of an electrophotographic photoreceptor according to the present invention, FIG. 2 is a cross-sectional view showing an electrophotographic photoreceptor according to an embodiment of the invention, and FIG. 3 is a diagram showing the relationship between the wavelength of light and the sensitivity. 4 to 12 are graph diagrams showing the relationship between the layer thickness and the gas flow rate of C%O%N when forming a layer. 1.2.3, 4: Cylinder, 5: Pressure gauge, 6; Valve, 7
: Piping, 8; Mixer, 9; Reaction container, 10; Rotating shaft, 1
3; electrode, 14; drum base, 15; heater, 16; high frequency power supply, 19; gate valve, 101; support, 10
3: Photoconductive layer, 104: μc-8i layer, 106;a
-8ill. Applicant's representative Patent attorney Takehiko Suzue] 6 Figure 1 Figure 2 Procedure Supplement j [:, Letter + 121 Japanese ql May 15th 11゛ Commissioner of the Office of Patent Attorney Uga Michibe 1, Patent Application for Indication of Case 1986 -256063 No. 2 Name of the invention Electrophotographic photoreceptor 3. Person making the amendment Relationship to the case Patent applicant (307) Toshiba Corporation (and 1 other person) 4. Agent 6 Subject of amendment 7. Contents of amendment (1) ) Amend the scope of the claims in a separate document. (2) In the specification, on page 8, line 7, the word "species" is corrected to "main". (3) In the specification, on page 22, line 4, "buffer stripes"
Correct the statement to "interference fringes". (4) In the specification, "layer pressure" is corrected to "layer thickness" on page 23, line 4, and page 23, line 8, respectively. (5) In the specification, page 24, line 15, rTor
Correct the word J to r TorrJ. (6) In the specification, on page 25, line 2, the phrase "film-formed" is corrected to "film-formed." (7) In the specification, on page 25, line 19, the word "blocking" is corrected to "blocking." (8) In the specification, page 26, line 5, “5iH4J
(9) In the specification, on page 29, line 9, "book" □ is corrected to "graph." 2. Claims (1) An electrophotographic photoreceptor comprising an electrically conductive support and a photoconductive layer formed on the electrically conductive support, the photoconductive layer comprising an amorphous silicon layer and an amorphous silicon layer. a microcrystalline silicon layer formed between the amorphous silicon layer and the conductive support; An electrophotographic photoreceptor characterized in that at least one selected type of atom forms a non-uniform concentration distribution in the layer thickness direction. (2) The electrophotographic photoreceptor according to claim 1, wherein the photoconductive layer contains at least one type of atom selected from Groups 1 and 1 of the periodic table. (3) The amorphous silicon layer of the light guide tn is characterized in that the concentration distribution of atoms governing the conductivity type and at least one type of atoms selected from carbon, nitrogen, and oxygen is such that the concentration on the conductive support side is low. Claim 1
The electrophotographic photoreceptor according to item 1 or 2. (4) The concentration distribution of at least one type of atom selected from carbon, nitrogen, and oxygen contained in the microcrystalline silicon layer is characterized in that the concentration is higher on the conductive support side. The electrophotographic photoreceptor according to any one of Items 1 to 3. (5) A patent characterized in that the concentration distribution of at least one type of atom selected from Group 1 and Group Ⅰ of the periodic table contained in the microcrystalline silicon layer has a higher concentration on the conductive support side. An electrophotographic photoreceptor according to any one of claims 1 to 1.

Claims (5)

[Claims] (1) In an electrophotographic photoreceptor having a conductive support and a photoconductive layer formed on the conductive support, the photoconductive layer includes an amorphous silicon layer and a conductive layer formed on the amorphous silicon layer. and a microcrystalline silicon layer formed between the amorphous silicon layer and the microcrystalline silicon layer,
1. An electrophotographic photoreceptor characterized in that atoms governing conductivity type and at least one type of atom selected from carbon, nitrogen, and oxygen form a nonuniform concentration distribution in the layer thickness direction. (2) The electrophotographic photoreceptor according to claim 1, wherein the photoconductive layer contains at least one type of atom selected from Group III and Group IV of the periodic table. (3) The amorphous silicon layer of the photoconductive layer is characterized in that the concentration distribution of atoms that dominate the conductivity type and at least one type of atom selected from carbon, nitrogen, and oxygen is such that the concentration on the conductive support side is low. An electrophotographic photoreceptor according to claim 1 or 2. (4) The concentration distribution of at least one type of atom selected from carbon, nitrogen, and oxygen contained in the microcrystalline silicon layer is characterized in that the concentration is higher on the conductive support side. The electrophotographic photoreceptor according to any one of Items 1 to 3. (5) A patent characterized in that the concentration distribution of at least one type of atom selected from Groups III and IV of the periodic table contained in the microcrystalline silicon layer has a higher concentration on the conductive support side. An electrophotographic photoreceptor according to any one of claims 1 to 4.