JPS6299759A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To obtain the photoconductive material which is capable of being produced with ease, and has a high resistance and excellent electrostatic chargeability, and has high photosensitive characteristics in ranges of a visible ray and a near infra-red ray by forming a blocking layer of an amorphous silicon or a microcrystalline silicon and a photoconductive layer of a laminating body composed of the N-type amorphous silicon contg. a hydrogen and the microcrystalline silicon respectively. CONSTITUTION:The blocking layer 103 composed of muC-Si or a-Si contg. the silicon atom as a base material and contg. the hydrogen atom and at least one or more atoms selected from a carbon, an oxygen and a nitrogen atoms, and the photoconductive layer 102 are laminated on a conductive substrate body 101 made of aluminium. Further, the photoconductive layer 103 is produced by laminating the N-type amorphous silicon a-Si layer 104 contg. the silicon atom as the base material, and contg. the hydrogen atom, and the microcrystalline silicon layer 105 contg. the silicon atom as the base material and contg. the hydrogen atom and at least one or more atoms selected from the carbon, the oxygen and the nitrogen atoms so as to make thick the concentration of said atoms on the side of the substrate in a direction of the thickness of the layer.

Description

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

[Prior art and its problems 1] Conventionally, inorganic materials such as CdS, zno, se, 5e-Te, or amorphous silicon, or poly-N-vinylcarbazole (PVC ) or trinitrofluorene (T
Organic materials such as NF) are used. however,
These conventional photoconductive materials have various problems in terms of photoconductive properties or manufacturing, and these materials are used depending on the purpose of use, sacrificing the properties of the photoreceptor system to some extent.

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, which lowers the manufacturing cost, and in particular, Se needs to be recovered, which adds to the recovery cost. Also,
In the Se or 3e-Te system, the crystallization temperature is 65°C
As a result, during repeated copying, problems arise in the photoconductive properties due to external electricity, etc., and therefore, the service life is short, making it impractical.

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 carcinogens and present human health concerns, and organic materials have poor thermal stability and abrasion resistance. , has the disadvantage of short lifespan.

On the other hand, amorphous silicon (hereinafter abbreviated as a-8i)
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-8t, attempts have been made to use a-3i as a photoconductive material for electrophotographic photoreceptors, and photoreceptors using a-3i are collected because they are non-polluting materials. It has advantages such as no need for treatment, higher spectral sensitivity in the visible light region than other materials, high surface hardness, and excellent wear 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 11-layer structure in which a blocking layer is provided between the photoconductive layer and the conductive support, and a surface charge retention layer is provided on the photoconductive layer. , satisfies these requirements.

By the way, a-3i is usually formed by a glow discharge decomposition method using silane gas, but at this time, a-3i is
Hydrogen is incorporated into 3i11, and the electrical and optical properties vary greatly depending on the difference in hydrogen seedlings. That is, as more hydrogen enters the a-3i film, the optical bandgap becomes larger and the resistance of the a-8i 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, if there are many depressions containing hydrogen in the a-5i film, depending on the film forming conditions, (S
! Those having a bonding structure such as H2)n 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, reducing the amount of hydrogen penetrating into a-8i reduces the optical band gap and its resistance, but increases photosensitivity to long wavelength light. However, less hydrogen-containing eggs means less hydrogen to combine with and reduce silicon dangling bonds. 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.

As a technique for increasing the sensitivity to long wavelength light, there is a method of mixing silane gas and germane Gel-14 and decomposing the mixture by glow discharge to produce a film with a narrow optical bandgap. Silane gas and G
Since the optimum substrate temperature is different for eH+, the produced film has many structural defects and cannot obtain good photoconductive properties. Furthermore, waste gas treatment is complicated because GeH+ waste gas becomes toxic gas when oxidized. Therefore, such technology is not practical.

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

[Means for Solving the Problems] The electrophotographic photoreceptor according to the present invention includes a conductive support, a blocking layer formed on the conductive support, and a blocking layer formed on the blocking layer. In the electrophotographic photoreceptor having a photoconductive layer, the blocking layer is formed of p-type or n-type amorphous silicon or microcrystalline silicon containing hydrogen and at least one element selected from carbon, nitrogen, and oxygen. The photoconductive layer contains the above n-type amorphous silicon containing hydrogen, at least one element selected from carbon, nitrogen, and oxygen, and hydrogen, and the photoconductive layer contains the above n-type amorphous silicon containing hydrogen, and at least one element selected from carbon, nitrogen, and oxygen. It is characterized by being composed of a laminate of at least one element and microcrystalline silicon in which a concentration gradient is formed in the layer thickness direction.

The present inventors have developed an electrophotographic photoreceptor of 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 (electrophotographic properties) and environmental resistance. As a result of various experimental studies, it was found that part or all of the photoconductive layer contains n-type amorphous silicon and at least one element selected from carbon, nitrogen, and oxygen; This invention was completed based on the idea that this object could be achieved by creating a laminate with microcrystalline silicon in which at least one selected element forms a concentration gradient in the layer thickness direction. It is something.

This invention will be specifically explained below.

The n-type amorphous silicon used in the photoconductive layer of this invention contains phosphorus P and arsenic A, which are elements in group V of the periodic table.
It is obtained by doping with s1 antimony sb, bismuth 13i, etc. In this case, n-type to n-type amorphous silicon is included, but n-type amorphous silicon is preferable in consideration of its properties as an electron photoreceptor.

Although the electrophotographic photoreceptor of the present invention uses an n-type amorphous silicon layer for the photoconductive layer, it has achieved high sensitivity to long wavelength light, particularly to semiconductor laser light having an emission wavelength around 790 nm. In particular, when used in an electrophotographic photoreceptor for a semiconductor laser printer, excellent electrophotographic properties and image quality can be provided.

Referring to FIG. 1, the n-type amorphous silicon used for the photoconductive layer of the electrophotographic photoreceptor of the present invention will be described. Figure 1 shows the conductivity and doping ratio (PH3/S
12Hs ). In Figure 1, the 0 triangle mark is the measured value σd in the dark, and the black circle mark is 7
Measured value σD (790nm
>, and the white circle indicates the measured value σp under white light (white light). When the doping ratio is 0, the conductivity σd
= 3.87xlO''', crp (790nm) = 1.15x10-', whereas as the doping ratio increases, the conductivity of both increases, and at a doping ratio of 33 ppm, cp (790nm)- 5,57x10-6, which is more than one order of magnitude higher. Also, crp (790 nm) = 5.28x10-8.

In this way, with the doping of PI-13, the measured value σd in the dark and the measured value σp in the light guide at 790 nm.
(790nm), and 10-6≦PH
3/S In the range of 12Hs≦10, σρ (790
nm) increases by one or more orders of magnitude, and the S/N can also increase by three orders of magnitude. Therefore, in order to increase the long-wavelength sensitivity of the photoconductive layer using the above-mentioned n-type amorphous silicon and to compensate for the decrease in the dark resistivity of the photoconductive layer due to the n-type amorphous silicon, the above-mentioned laminated structure is adopted. It can be fully put to practical use as an electrophotographic photoreceptor for semiconductor laser printers.

Next, with reference to FIG. 2, the optical band gap, activation energy (8E), and doping ratio (PH3/S 12Hs) will be explained. Second
In the graph shown, the vertical axis represents the activation energy (ΔE) and the optical band gap (eV), and the horizontal axis represents the doping ratio (PH3, 'S i 2 H6). In this graph, the white circles indicate the optical band gap, and the black circles indicate the activation energy. As is clear from Figure 2, the doping ratio (PH3/S 12t-1s
), the optical bandgap remains approximately constant even if PH3/S 12H is changed, whereas the activation energy is
It becomes smaller as the doping of s is increased. From this, when n-type amorphous silicon is used for the photoconductive layer, high sensitivity in the long wavelength region is achieved because the Fermi level is shifted to the conductor side.

Amorphous silicon (hereinafter referred to as a-5i) or microcrystalline silicon (hereinafter referred to as μc-si) is used for the blocking layer of the electrophotographic photoreceptor of the present invention. μC-8i is clearly distinguished from a-8i and polycrystalline silicon (polycrystalline silicon) by the following physical characteristics. That is, in X-ray diffraction measurements, since a-8i is amorphous, only a halo appears and no diffraction pattern can be observed, but μ
C-S+ shows a crystal diffraction pattern with 2θ around 27 to 28.5°. Furthermore, while polycrystalline silicon has a dark resistance of 10”Ω・α, μC-8i
has a dark resistance of 1Q11Ω·cm or more. This μc-
sr is formed by aggregation of microcrystals having a grain size of approximately several tens of angstroms or more.

A blocking layer with such μC-8i is a-
Similarly to 8t, it can be produced by depositing μC-8i on a conductive support using silane gas as a raw material using the high frequency glow tllN decomposition method. In this case, if the temperature of the support is set higher than in the case of forming a-5i, and the high frequency power is also set higher than in the case of forming a-3i, it becomes easier to form μc-sr. 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.

Further, by using a gas obtained by diluting the raw material gas SiH+ and a high-order silane gas such as 5i2t-1s with hydrogen, μC-8i can be formed with higher efficiency.

FIG. 3 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 valve 6 and piping 7 for flow rate adjustment. 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 valve 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 create a pressure inside the reaction vessel 9 of about 11 Torr. Exhaust below. Next, cylinder 1
．． From 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, and the heater 15 heats the drum base 14 to a constant temperature, and the high frequency power supply 16 supplies high frequency current between the electrode 13 and the drum base 14, creating a glow between them. form a discharge.

As a result, a-8i is deposited on the drum base 14.

Note that N20. NH3, NO2, N2.

By using CH4, C2H4,02 gas, etc.
These elements can be contained in a-8i.

In this way, the electrophotographic photoreceptor according to the present invention has a conventional a
Similar to those using -3i, it can be manufactured using closed system manufacturing equipment, so it is safe for the human body. In addition, this electrophotographic photoreceptor has excellent heat resistance, M moisture resistance, and abrasion resistance, so there is little deterioration even after repeated use over a long period of time (it has the advantage of a long life. Since a long wavelength sensitizing gas 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 light resistance and light resistance become harmonious, and the photoconductive properties are improved. μC-
The optical energy gap Ea of 8i is the optical energy gap Ea of a-3i (1,65 to 1.70 eV
) is small compared to In other words, the optical energy gap of μC-8i changes depending on the crystal grain size and crystallinity of the μC-8i microcrystal, and as the crystal grain size and crystallinity increase, the optical energy gap decreases. The optical energy gap approaches the 1.1 eV of crystalline silicon. By the way, the μC-8i layer and the a-8i layer absorb light with a larger energy than this optical energy gap, and transmit light with a smaller energy. Therefore, a-3i absorbs only visible light energy, but μC-8+, which has a smaller optical energy gap than a-8i, can also absorb near-infrared light, which has a longer wavelength and lower energy than visible light. I can do it. Therefore, μC-5i has high photosensitivity over a wide wavelength range.

μC-3i having such characteristics is suitable as a photoreceptor material for a laser printer using a semiconductor laser as a light source. When the a-3i is used as a photoconductor for a laser printer, the light wavelength of the semiconductor laser is 790 nm and the a-8i
Since this is better than the wavelength region where the photoreceptor 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 capability of the semiconductor laser, which poses a practical problem. On the other hand, when the photoreceptor is formed with μC-8i,
Since its high sensitivity region extends to the near-infrared region, it can be used as a semiconductor photoreceptor for 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-8i contains hydrogen.

Hydrogen doping into the μC-3i layer is carried out, for example, by glow discharge decomposition, by introducing a silane-based raw material gas such as Sil'4 and 5i2Hs into a reaction vessel and a carrier gas such as hydrogen. It may be discharged, a mixed gas of silicon halide such as SiF+ and 5iC1+, and hydrogen gas may be used, or a mixed gas of silane-based gas and silicon halide may be reacted. Furthermore,
The μc-sr layer can be formed not only by the glow discharge decomposition method but also by a physical method such as sputtering. Note that the photoconductive layer containing .mu.c-sr preferably has a thickness of 1 to 80 .mu.m, more preferably 5 to 50 .mu.m, in view of photoconductive properties.

Substantially the entire region of the photoconductive layer may be formed of μc-s i, or may be formed of a mixture or a laminate of a-8i and μc-8i. The W1 power is higher for the laminate, and the photosensitivity is higher for the mixture in the long wavelength region of the infrared region, although it depends on the volume ratio, and the two are almost the same in the visible light region.

For this reason, depending on the use of the photoreceptor, substantially all areas may be made into μc-sr, or a mixture or! It may be composed of an a-layer body.

Preferably, μc-sr is doped with at least one element selected from nitrogen N, carbon C, and oxygen O. This makes it possible to increase the dark resistance of μc-s 1 and improve the photoconductive properties.

These elements precipitate at the grain boundaries of μc-si and act as terminators of silicon dangling bonds, reducing the density of states existing in the forbidden band between bands,
It is thought that this increases the dark resistance.

Preferably, a blocking layer or a blocking layer is provided between the conductive support and the photoconductive layer. This blocking layer enhances the charge retention function on the surface of the photoconductive member by suppressing the flow of charge between the conductive support and the photoconductor, thereby increasing the charging ability of the photoconductive member.
Melt. 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 is μc-
The blocking layer may be formed using s i or a-3t.

In order to make μc-s i and a-8i p-type, they must be doped with elements belonging to Group Ⅰ of the periodic table, such as boron B, aluminum AI, gallium Qa, indium ln, and thallium T1. is preferable, μc-s
In order to make the r layer n-type, it is preferable to dope it with an element belonging to VM of the periodic table, such as nitrogen N, phosphorus P, arsenic AS, antimony sb, and bismuth 3i.

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.

The leading 'i4 layer μC-S + has a refractive index of 3 to 4.
Because it is relatively large, light reflection easily occurs on the surface. When such light reflection occurs, light a absorbed by the photoconductive layer
As a result, the optical loss increases. 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 the surface layer, the charging ability is improved, and the charge can be easily deposited on the surface. The materials forming the surface layer include Si3N+, SiO2, and SiC.

There are unbound compounds such as Δ1203, a-8iN:H, a-3iO:Hl and a-3iC:H, and organic materials such as polyvinyl chloride and polyamide.

As described above, a photoconductive member applied to an electrophotographic photoreceptor includes a blocking layer formed on a support, a photoconductive layer formed on this blocking layer, and a surface layer formed on this photoconductive layer. The structure is not limited to one in which a charge transfer layer (CTL) is formed on a support, and a functionally separated structure in which a charge transfer layer (CTL) is formed on the charge transfer layer and a charge generation layer (CGL) is formed on the charge transfer layer is also possible. 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. This charge generation layer is
Part or all of the layer is made of μC-8i or a-3i, preferably with a thickness of 1 to 10 μm.

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. Charge transfer 1 can be formed by a-8i.

In order to increase the dark resistance and improve the charging ability, it is preferable to light-dope an element belonging to either Group 1 or Group 2 of the periodic table.

Furthermore, 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 or more of the elements C, N, and O may be contained. 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 preferably 3 to 80 um.

By providing a blocking layer, even in a functionally separated type photoreceptor having a KM transfer layer and a charge generation layer 1, the charge retention capacity can be increased and the charging ability can be improved. Note that whether the blocking layer is p-type or n-type is determined depending on its charging characteristics. This blocking layer may be formed of a-3i or μc-
It may be formed by s i.

The feature of the invention according to the application is that the blocking layer is made of ρ-type or n-type amorphous silicon containing silicon atoms as a host, hydrogen, and at least one element selected from carbon, nitrogen, and oxygen. Alternatively, the photoconductive layer is formed of microcrystalline silicon, and the photoconductive layer contains the above n-type amorphous silicon containing hydrogen, at least one element selected from carbon, nitrogen, and oxygen, and hydrogen, and the photoconductive layer contains hydrogen and at least one element selected from carbon, nitrogen, and oxygen. At least one element selected from oxygen is present in the leopard thickness direction! ■It consists of a laminate with microcrystalline silicon forming a gradient.

[Example] Next, the structure of the layers of an electrophotographic photoreceptor embodying the present invention will be described with reference to Figures 4.5.6.

In FIG. 4, an aluminum conductive support 101
On the top is μC-3i or a- which has p-type or n-type characteristics and contains silicon atoms as a host and hydrogen, and further contains at least one or more of C1○ and N atoms.
A blocking layer 103 made of 8i and a photoconductive layer 102
are laminated. The photoconductive layer 102 further includes an n-type amorphous silicon a-8ili 104 containing silicon atoms as a matrix and hydrogen, and a microcrystalline silicon layer 105 containing hydrogen as a matrix on silicon atoms.
are laminated, and this microcrystalline silicon layer 1
05 contains at least one or more of C, O, and N atoms. Furthermore, at least one of C10 and N atoms contained in this microcrystalline silicon has a 1 degree gradient in the thickness direction so that it is denser on the support side.

According to the electrophotographic photoreceptor of the present invention, the blocking layer 1
03 is C1○, p-type or n-type μ(, -8i or a-8
It is formed from i. Such a blocking layer and a-8in structure can prevent N charges having a polarity opposite to those charged during charging from moving from the support 101 to the photoconductive layer 102 . That is, the charging ability (charge retention function) of the photoconductive layer can be further improved.

The content of C, O, and N atoms contained in the blocking layer 103 is preferably 1 to 20 at%, and the content of elements belonging to Group 1 or Group V of the periodic table is lXl0
-3 to 5 atom % is preferred.

The thickness of the blocking layer is preferably 100 μm to 10 μm, more preferably 0.1 μm to 3 μm.
is preferred.

n-type a-sin1 formed in the photoconductor 11102
Since o4 contains hydrogen with the silicon atom S1 as the host, it is highly sensitive to long wavelength light and exhibits good spectral sensitivity, which allows it to be used in a wide range from the visible light #A region to the near-infrared region. High sensitivity is achieved within this range. - The μC-8i layer 105 of the force guiding conductive layer 102 can further enhance the sensitivity in the near-infrared region among the above-mentioned wavelength regions.

In this way, the photoconductive layer 102 is connected to the a-3i layer 104 and the μC-
F! with 8i layer 105! By forming the four-layer structure, a highly sensitive electrophotographic photoreceptor can be obtained.

In the photoconductive layer 102, the n-type a-3i layer 104 is doped with an element belonging to Group V of the periodic table preferably in an amount of 1 x 10 to 1 x 10' atomic %. a-
The thickness of the 8i layer 104 is preferably 1 to 20 μm.

On the other hand, by lightly doping the a-5i layer 104 with an element belonging to Group 1 of the periodic table, its dark resistance can be increased and the charge retention function can be indirectly improved. The doping level is preferably 1 x 10-' to 1 x 103 atomic %. The layer thickness of the μC-3i layer 105 is 1 to 20
It is preferable to form it in μm. Also, μC-8iF!
The atomic weight of C10 and N contained in 105 is such that the photoconductivity does not deteriorate, and the preferable content is 0.
It is 1 to 10 at%.

As shown in FIG. 5, photoconductivity 1i! At 1102,
The n-type a-3i layer 104 and the μC-8i layer 105 containing one or more of C, 0, and N atoms (the Q position is
Contrary to the position shown in the figure, an n-type a-8i layer 104 may be formed on the μC-S: layer 105.

Furthermore, as shown in FIG. 6, a surface layer 106 may be formed on the photoconductive layer 102. In this case, the surface layer 106
is a-8i (a-8i C:H, a-3iO; H
, a-8iN; Hla-8iCN:H, etc.). This protects the surface of the photoconductive layer and improves environmental resistance and charging ability. The content of C, O, and N is
Preferably, it is 10 to 50 atom %.

Next, embodiments of the invention will be described.

First, in this Example 1, the blocking layer was formed of microcrystalline silicon μC-SR.

An AI 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. The inside of the reaction vessel is evacuated to about 0.1 torr or less by a diffusion pump (not shown).

At the same time, the drum substrate is heated and maintained at approximately 400°C.

Then H2 gas at a flow rate of 10003CCM, 200S
C, CM (7) flow M (7) 100% SiH4, trs,
B2 with a flow rate ratio of 10゛3 to this SiH + gas flow
H6 gas and 11005 CC of CH4 gas were mixed and supplied to the reaction vessel. Thereafter, the inside of the reaction vessel was evacuated using a mechanical booster pump and a rotary pump, and the pressure was adjusted to 1 Torr. Base body 14 by motor 18
300 at 13.56M) tz to the electrode while rotating
By applying high frequency power of W (watts), li? Plasma of SiH4, B2Hs and CH4 is generated between M and the drum base (glow discharge). Under these conditions, approximately 1
Film formation was continued for 5 minutes, and a blocking material 103 made of microcrystalline silicon μC-8i was deposited on the support 101.
was formed to have a thickness of 1.0 μm.

After forming the blocking layer, the flow rate of 100% 5i2H+ gas was increased to 808 CCM, P l
-13 gases were introduced into the reaction vessel so that PH3/S i H4 = 2X 10''. Similar to the case of forming the blocking layer at a reaction pressure of 0.8 Torr, high frequency power of IKW at 13.56 MHz is applied by the high frequency layer 116 to generate a glow discharge. The 2-hour open film formation was continued under these conditions to form an n-type a-8i layer with a thickness of 14 μm.

After forming the n-type a-3i layer, H2 gas was heated to 1100OSC.
C, 100% 3i2t-1 + gas flow □□□ 300S
1108 CC of CCM and NH3 gas are introduced respectively. A high frequency power of 13.56 MHzr200 W is applied by a high frequency 7Iflli16 at a reaction pressure of 0.8 torr. After continuing film formation under these conditions for 165 hours, the supply of electricity and gas was stopped, and a-8ilW having a thickness of 8 μm was formed. A photoconductive layer is formed by laminating the n-type a-8i layer and the μC-8i layer in this manner.

Light guide N! ! After the film formation, a flow of 100% SiH + gas (300 sccM of 1 and 3508 CCM of CH4 gas is introduced, respectively. With a reaction pressure of 1 Torr, a high frequency power of 200 W at 13.56 MHz is applied by the high frequency power source 16. After continuing film formation under these conditions for 15 minutes, the supply of electricity and gas was stopped, and a surface layer with a thickness of 0.7 μm was formed.

When the photoreceptor thus formed was mounted on a laser printer equipped with a semiconductor laser with an oscillation wavelength of 790 nm to form an image, an applied voltage of +6.0 KV (kilovolts) (drum inflow current 0.1 mA) was applied. In contrast, a surface potential of 40t)V was obtained, and the maximum half-exposure was 7.5erg/
crIi and good results were obtained.

Furthermore, the amount of exposure on the body surface is 35 e r Q /
The residual potential with respect to tri was 30V, which was a good result.

11''2 In this Example 2, the blocking layer was formed of amorphous silicon a-3i.

An A1 drum (diameter 80 mm, length 350 mm) serving as a conductive substrate was degreased with trichlorene, washed and dried, and then loaded into a reaction vessel. The surface of this drum is subjected to rIi treatment, alkali treatment, or sand 1-last treatment as necessary to prevent interference. The inside of the reaction vessel is evacuated to about 0.1 torr or less by a diffusion pump (not shown).

At the same time, the drum substrate is heated and maintained at approximately 400°C.

Then 100% S i H4 with a flow rate of 200SCCM
gas, the flow flk ratio ffi for this 3iH + gas flow day
10' (7) B2 H6 scraps, abi 100sccN
1 of CH4 gas was mixed and supplied to the reaction vessel.

Thereafter, the inside of the reaction vessel was evacuated using a mechanical booster pump and a rotary pump, and the pressure was adjusted to 1 Torr. The base 14 is rotated by the motor 18, and the electric current
By applying high frequency power of 300 W (watts) at 13.56 MH2, SiH+, B
2Hs and CH4 plasma is generated (glow discharge).

Under these conditions, film formation was continued for about 15 minutes, and a blocking layer 103 made of amorphous silicon was formed on the support 101.
was formed to have a thickness of 1.6 μm.

After forming the blocking layer, increase the flow rate of 100% 5i2H+ gas to 808CC~1,P)
-13 gas P)-13/S i)-14=2X 1
Each gas was introduced into the reaction vessel so that the temperature was 0'.

As in the case of forming the blocking layer at a reaction pressure of 0.8 Torr, the high frequency power source 16 was used to generate 13.56 M
High frequency power of 1 KW at Hz is applied to generate a glow discharge. Film formation continued under these conditions for 2 hours, resulting in a film thickness of 14 μm.
A-3i skin of n-type was formed.

After forming the n-type a-8i layer, H2 gas 1000SCCM
, the flow rate of 100% Si H4 gas is 300SCCM,
10,800M of NH3 gas is introduced into each case. 13.5 torr by the high frequency power supply 16 with the reaction pressure being 0.7 Torr.
6M)-1zr Apply high frequency power of 200W. After film formation continued under these conditions for 1.5 hours, the supply of electricity and gas was stopped, and a μC-8i layer with a thickness of 8 μm was formed. In this way, a photoconductive layer is formed by stacking the n-type a-8i layer and the μC-3iWJ.

After forming the photoconductive layer, the flow rate of 100% Si H4 gas was introduced at 300 SCCM, and the flow rate of CH4 gas was introduced at 3508 C01\4. High frequency electricity is generated when the reaction pressure is 1 torr! 1
6, a high frequency power of 200 W is applied at 13.56 M1-1z. After continuing film formation under these conditions for 1.5 hours, the power and gas supply was stopped, and a-3i film with a film thickness of 0.7 μm was deposited.
formed a layer.

When the photoreceptor thus formed was mounted on a laser printer equipped with a semiconductor laser with a oscillation wavelength of 790 nm to form an image, an applied voltage of +6.0 KV (kilovolts) (drum inflow current of 0.1 mA) was obtained. >A surface potential of 500V was obtained, and the half-reduction exposure was s, oerg,
, 'c*, and good results were obtained.

Furthermore, the exposure output on the body surface is 358 r g/cp
A good result was obtained with a residual potential of 40 V for i.

[Effects of the Invention] According to the present invention, the light source has high resistance and excellent charging characteristics, has high light sensitivity characteristics in visible light and near-infrared light #4Fft, is easy to manufacture, and has high practicality. A conductive member can be obtained.

[Brief explanation of drawings]

Figure 1 shows the n-type amorphous silicon a-3i of this invention.
Figure 2 is a diagram showing the relationship between the conductivity of W4 and the doping ratio (PH3/S 12H6), Figure 2 is a diagram showing the relationship between the optical band gap and the doping ratio with activation energy, and Figure 3 is a diagram showing the relationship between the doping ratio and the optical band gap. 4 to 6 are cross-sectional views showing photoconductive members according to embodiments of the present invention. 1.2.3.4: Cylinder, 5; Pressure gauge, 6; valve, 7
; Piping, 8: Mixer, 9; Reaction container, 10; Rotating shaft, 1
3; Electrode, 14 Nidram base, 15; Heater, 16; High frequency power supply, 19 Nige-1 valve, 101; Support, 1
02; Photoconductive layer; 103; Blocking layer; 106; Surface layer. Applicant's agent Patent attorney Takehiko Suzue PH3/Si2H6

Claims (3)

[Claims] (1) An electrophotographic photoreceptor having a conductive support, a blocking layer formed on the conductive support, and a photoconductive layer formed on the blocking layer,
The blocking layer is formed of p-type or n-type amorphous silicon or microcrystalline silicon containing hydrogen and at least one element selected from carbon, nitrogen, and oxygen, and the photoconductive layer is formed of p-type or n-type amorphous silicon or microcrystalline silicon containing hydrogen and at least one element selected from carbon, nitrogen, and oxygen. amorphous silicon, at least one element selected from carbon, nitrogen, and oxygen, and hydrogen, and the at least one element selected from carbon, nitrogen, and oxygen forms a concentration gradient in the layer thickness direction. An electrophotographic photoreceptor comprising a laminate with microcrystalline silicon. (2) The photoconductive layer contains at least one element selected from elements belonging to Group III or V of the periodic table. Photographic photoreceptor. (3) The electrophotographic photoreceptor according to claim 1, wherein a surface layer is formed on the photoconductive layer.