JPS6228752A - Photosensitive body - Google Patents

Abstract

PURPOSE:To improve the mechanical and the optical properties and the stability of the titled body by laminating the prescribed layers composed of such as a specific amorphous hydrogenated silicon (a-Si:H) etc. respectively. CONSTITUTION:An electric charge blocking layer 44 composed of a-Si:H contg. >=1 kind atoms selected from a carbon, nitrogen, and an oxygen atoms, and an electric charge transfer layer 42 composed of a-Si:H contg. the nitrogen atom and an electric charge generating layer 43 composed of a-Si:H are laminated on a substrate 41. And the first intermediate layer 47 composed of a-Si:H and dopped with the group IIIa or Va element of the periodic table, the second intermediate layer 46 composed of a-Si:H contg. at least one kind atom selected from the carbon, the nitrogen and the oxygen atoms and the surface reforming layer 45 composed of a-Si:H contg. large amounts of the atom are laminated on the substrate 41 to form the photosensitive body 39. By providing the layers 45-47, the mechanical strength of the titled body becomes large. The adhesive property, the anti-fatigue property against a light and the anti-chemical stability of the layers 45 and 43 are improved. The effects as prescribed above are obtd. by merely using a fluorinated silicon or by jointly using the fluorinated silicon and the prescribed silicon.

Description

[Detailed description of the invention]

B. Industrial Application Field The present invention relates to a photoreceptor, for example, an electrophotographic photoreceptor. Conventional technology Conventionally, as an electrophotographic photoreceptor, Se or Se has A S
Photoreceptor doped with % T e , S b etc., Zn
Photoreceptors in which O or CdS is dispersed in a resin binder are known. However, these photoreceptors have problems in terms of environmental pollution, thermal stability, and mechanical strength. On the other hand, electrophotographic photoreceptors using amorphous silicon (a-3i) as a matrix have been proposed in recent years. a-3t has a so-called dangling bond in which the bond of 5t-3i is broken, and many localized levels exist within the energy gap due to this defect. For this reason, popping conduction of thermally excited carriers occurs, resulting in a small dark resistance, and photoexcited carriers are trapped in localized levels, resulting in poor photoconductivity. Therefore, we replaced the above defects with hydrogen atoms (
■]) By compensating and bonding H to Si,
Filling of dangling bonds is performed. Such amorphous hydrogenated silicon (hereinafter referred to as a-3
It is called i:H. ) has a resistivity in the dark of 108 to 10
9Ω-■, which is about 1 compared to amorphous Se.
It's even lower than 1/10,000. Therefore, a photoreceptor consisting of a single layer of a-3i:H has the problem of a fast dark decay rate of surface potential (low initial charging potential). When irradiated with light of -3i
An electrophotographic copying machine incorporating a system photoreceptor 9 is shown. According to this copying machine, a glass document mounting table 3 on which a document 2 is placed and a platen cover 4 that covers the document 2 are disposed in the upper part of a cabinet 1. Below the document table 3,
An optical scanning table consisting of a first mirror unit 7 equipped with a light source 5 and a first reflecting mirror 6 is provided so as to be movable linearly in the left-right direction of the drawing, and the optical path length between the document scanning point and the photoreceptor is kept constant. The second curler unit 20 moves according to the speed of the first mirror unit, and the reflected light from the document table 3 passes through the lens 21 and the reflection mirror 8 onto the photosensitive drum S as an image carrier. The light enters in a slit shape. Around the drum 9, a corona charger 10,
A developing device 11, a transfer section 12, a separation section 13, and a cleaning section 14 are arranged, and the copy paper 18 fed from the paper feed box 15 via each paper feed roller 16, 17 is further processed after the toner image on the drum 9 is transferred. The image is fixed by the fixing unit 19 and then ejected to the tray 35. In the fixing section 19, the developed copy paper is passed between a heating roller 23 containing a heater 22 and a pressure roller 24 to perform a fixing operation. However, photoreceptors with a-3t:H surfaces are susceptible to surface chemical stability, such as the effects of long-term exposure to the atmosphere and moisture, and the effects of chemical species generated by corona discharge. , has not been sufficiently investigated so far. For example, items that have been left for more than a month will be affected by moisture.
It is known that the receptor potential is significantly reduced. On the other hand, amorphous hydrogenated silicon carbide (hereinafter a-3iC:H
It is called. ), its manufacturing method and existence are described in "Ph1l. Mag, Vol. 35" (1978), etc., and its characteristics include high heat resistance and surface hardness,
a-3i: High dark resistivity (10'2~
It is known that the optical energy gap varies over a range of 1.6 to 2.8 eV depending on the amount of carbon. However, there is a drawback that the long wavelength sensitivity is poor because the hand gear knob expands due to the carbon content. An electrophotographic photoreceptor combining such a-3iC:H and a-3i:H has been proposed, for example, in Japanese Patent Application Laid-Open No. 127083/1983. According to this, a-3isH
The layer is a charge generation (photoconductive) layer, and below this charge generation layer is a
-3iC:H layer is provided, the upper layer a-3i:H provides photosensitivity in a wide wavelength range, and the lower layer a-3iC:H forming a heterojunction with the a-3i:H layer has a charged potential. We are working to improve this. However, the dark decay of the a-3i:H layer cannot be sufficiently prevented, and the charging potential is still insufficient to be practical.
The presence of HJi causes poor chemical stability, mechanical strength, heat resistance, etc. On the other hand, JP-A-57-17952 discloses a-3i:
A first a-3iC:H layer is formed as a surface modification layer on the charge generation layer made of H, and a second a-3iC:H layer is formed on the back surface (support electrode side).
a-3iC:H layer is formed. In addition, as related to this known technology,
As seen in Japanese Patent No. 23543, a slope N(a-S i , -xCx : H) is provided between the charge generation layer and the first and second a-S i Cs H layers, In this graded layer, X=0 on the a-3i:H side, and a
-3iC: A photoreceptor in which X=0.5 on the H layer side is known. However, when the present inventor conducted a study on the above-mentioned known photoreceptor, it was found that the effect of providing the surface modification layer is not so pronounced, especially in continuous repeated use. That is, during continuous running of 200,000 to 300,000 times, the a-3iC layer on the surface is mechanically damaged by about 70,000 to 80,000 times, and white streaks and white spots caused by this occur as image defects, so the durability is low. Rigidity is not sufficient. In addition, light resistance fatigue occurs during repeated use, and image blurring occurs.
The electrical and optical characteristics are not always stable, and the usage environment (temperature,
The influence of humidity) cannot be ignored. Furthermore, it is necessary to further improve the adhesion between the surface modified layer and the charge generation layer. The object of the present invention is to provide excellent adhesion between a surface modified layer and a charge generation layer, strong resistance to mechanical damage, and excellent rigidity resistance.
Stable image quality without image blurring is obtained, there is little optical fatigue during repeated use, the residual potential is low, and the characteristics are compatible with the usage environment (
The purpose of the present invention is to provide a photoreceptor that is stable regardless of temperature and humidity. 20 Structure of the invention and its effects, that is, the present invention provides a charge blocking layer made of amorphous hydrogenated and/or fluorinated silicon containing at least one of carbon atoms, nitrogen atoms, and oxygen atoms; an amorphous hydrogenated and/or fluorinated silicon containing yl-17; a first intermediate layer doped with an element of group IIIa or group Va of the periodic table and made of amorphous hydrogenated and/or fluorinated silicon; a second intermediate layer made of amorphous hydrogenated and/or fluorinated silicon containing at least one of carbon atoms, nitrogen atoms, and oxygen atoms; The present invention relates to a photoreceptor in which a surface-modified layer made of amorphous hydrogenated and/or fluorinated silicon containing a larger amount than the second intermediate layer is sequentially laminated. According to the present invention, the surface-modified layer contains at least one atom of carbon, nitrogen, and oxygen, and the second and first intermediate layers are provided below this layer, so that mechanical damage There is no deterioration in image quality due to white streaks, etc.
It has excellent rigidity. Furthermore, in the present invention,
Since the first and second intermediate layers are provided between the surface modified layer and the charge generation layer, the adhesion between the surface modified layer and the charge generation layer is improved. In addition, since the surface modification layer and intermediate layer are provided on the charge generation layer, in addition to the above, it has excellent light fatigue resistance during repeated use, has no image fading, and has low residual potential.
It has been confirmed that the electrical and optical characteristics are always stable and are not affected by the usage environment. E. Examples Hereinafter, the present invention will be explained in detail with reference to examples. FIG. 1 shows an a-3i electrophotographic photoreceptor 3S for positive charging according to this embodiment. This photoreceptor 39 is A1
A-3i:H (which is heavily doped with a Group Va element of the periodic table (for example, phosphorus) and contains at least one of C, N, and 0) is placed on a drum-shaped conductive support substrate 41 such as
−3i(C)(N)(0):H. ) consisting of N
° type charge profking layer 44 and a-3i:H (hereinafter referred to as a-3iN:H) which is light-doped with an element of group ff1a of the periodic table (for example, boron) to become intrinsic and contains N. A charge transport layer 42 made of a-3i:H, a charge generation layer 43 made of a-3i:H (without impurity doping or made intrinsic), and a P-type or A first intermediate N47 made of N''' type amorphous hydrogenated silicon and nI of the periodic table.
Amorphous hydrogenated silicon doped with a group A or group Va element to make it P-type, N-type, or intrinsic (or without impurity doping) and containing at least one of N, C, and O (this is called a-3i (C) (N) (0
): Represented as H. ), and a-3i (C) (N) which is doped with a group A or Va group element and becomes P-type or N-type or intrinsic (or without doping) and a-3i (C) (N) It has a structure in which a surface modified layer 45 made of (0):H is laminated. The charge generation layer 43 has a dark resistivity ρ. The ratio of resistivity ρ when irradiated with light is sufficiently large as an electrophotographic photoreceptor, and the photosensitivity (particularly to light in the visible and infrared regions) is good. In addition, in the range of 0 to 70%, the carbon atom content of each of the above layers has a nearly linear relationship with the optical energy gear (Eg, opt) as shown in Figure 2. The a-3iC:H can be defined by replacing the atomic content with the optical energy gap.Also, if the carbon atom content is appropriately selected, the specific resistance will increase as shown in curve a in Figure 3. , a remarkable effect of improving the charging potential holding ability can be obtained. That is, as shown by curve a in FIG. 3, when the carbon atom content is 30
When ~90% a-3iC:H is used, its resistivity varies with carbon content and is greater than 10'2 Ω-(2). The above tendency is that a-3iN containing N or 0 instead of carbon
The same applies to :H, a-3iO:H. The above-mentioned layer 45 is indispensable for modifying the surface of the photoreceptor and making the a-3i-based photoresistance practically excellent. That is, it enables the basic operations of an electrophotographic photoreceptor, such as charge retention on the surface and attenuation of the surface potential due to light irradiation. Therefore, the repetitive characteristics of charging and optical attenuation become very stable, and good potential characteristics can be reproduced even if left for a long period of time (for example, one month or more). On the other hand, in the case of a photoreceptor having a-3i:H as its surface, it is easily affected by humidity, air, ozone atmosphere, etc., and the potential characteristics change significantly over time. In addition, since the layer 45 has a high surface hardness, it has abrasion resistance during processes such as development, transfer, and cleaning, and also has good heat resistance, so a process that applies heat such as adhesive transfer can be applied. . In order to comprehensively achieve the excellent effects described above, it is important to select the composition of the layer 45. That is, when containing carbon atoms, Si+C=100at
When omic% (hereinafter, atomic% is simply expressed as %), 1%≦(C)590%, furthermore 10%≦(
C) Desirably 570%. Due to this C content, the above-mentioned resistivity becomes the desired value, and the optical energy gap becomes approximately 2.5 eV or more, and the irradiated light is a-3i due to the so-called optically transparent window effect for visible and infrared light. : It becomes easier to reach the H layer (charge generation layer) 43. However, if the C content is 1% or less, disadvantages such as mechanical damage occur, and the specific resistance tends to fall below a desired value, and part of the light is absorbed by the surface layer 45, reducing the photosensitivity of the photoreceptor. It becomes easier to do. Furthermore, if the C content exceeds 90%, the amount of carbon in the layer increases, and semiconductor properties are likely to be lost, and a
-3iC: Since the deposition rate when forming the H film by the glow discharge method tends to decrease, the C content is preferably 90% or less. Similarly, in the case of layer 45 containing nitrogen or oxygen,
1%≦(N)590% (furthermore, 10%≦(N)570%
) is good, 0%

[0]≦70% (even 5%≦

[0]
≦30%) is good. In order to improve the charging ability, the surface modified layer 45 may have a high resistance. For this purpose, the surface modified layer may be made intrinsic. When used with positive or negative charging, in order to facilitate the injection of electrons or holes from the intermediate layer into the surface-modified layer and to minimize the residual potential, the surface-modified layer may be of P or N type. good. The amount of impurity doped in each case (at the time of glow discharge decomposition described later) may be as follows. Intrinsicization: BzHb/S i H42-50 Capacity ppI
I+P type: Bz Hb/S i Ha 50~
1000 volume itppm N type: P H3/S i H
a 1 to 1000 ppm, and the layer 45 is a-3
It may be composed of iCO3a-3iN, a-3iO1a-3i02, etc., and it is also important to select the film thickness within the range of 400 people≦t≦5000 people (especially 400 people≦t≦2000 people. That is, If the film thickness exceeds 5000 mm, the residual potential vR becomes too high and the photosensitivity decreases, making it easy to lose the good characteristics of the a-3i type photosensitive. In this case, charges are no longer charged on the surface due to the tunnel effect, resulting in an increase in dark decay and a decrease in photosensitivity.As for the second intermediate layer 46, in order to reduce the residual potential, The intermediate layer is made of P to enable charge injection from the generation layer.
Or it may be N type. The doping amount for controlling the conductivity type may be the same as that for the surface modification layer. Further, the content of C, N, and 0 is made smaller than that of the layer 45. That is, Q<(C)610%, 0<(N)610%
, 0<(0)≦5%. The thickness of this intermediate layer is preferably 50 to 5,000 people, but if it exceeds 5,000 people, the same phenomenon as described above tends to occur, and if it is less than 50 people, the effect as an intermediate layer becomes poor. Preferably, the thickness is 100 Å or more and 1000 Å or less. The first intermediate layer 47 is provided to improve sensitivity, reduce residual potential, improve the adhesion of the surface modification layer and intermediate layer 46, and stabilize the image. The intermediate layer 47 needs to be of P or N type in order to improve the above characteristics. The impurity doping amount is (PH3)/(S
i H4) = 1 to 1000 (preferably 10 to 5
00) Capacity ppm, CBZH &) / (S i Ha
) = 10 to 1000 (preferably 50 to 500) capacity pp+++. The thickness of this intermediate layer is preferably 50 to 5,000 people, but if it exceeds 5,000 people, the same phenomenon as described above is likely to occur, and if it is less than 50 people, the effect as an intermediate layer will be poor. Regarding the charge generation layer 43, in order to improve the charging ability,
The resistance of the charge generation layer may be increased. For this purpose, the charge generation layer may be made intrinsic. For this purpose, it is preferable that BZHb/SiH4=1 to 20 ppm by volume. Further, the charge generation layer has a thickness of 1 to 10 μm, preferably 5 to 7 μm.
It is better to set it to m. If the thickness of the charge generation layer 43 is less than 1 μm, the photosensitivity will not be sufficient, and if it exceeds 10 μm, the residual potential will increase, which is insufficient for practical use. The charge transport layer 42 may be made intrinsic in order to optimize charging ability and sensitivity. The doping amount for making it intrinsic is
(B2H6)/(S i H4)= 1~2000
Capacity ppm is optimal. However, since the above value depends on the C concentration, it is not necessarily limited to the above value. The thickness of the charge transport layer is preferably 10 to 30 μm. The composition of the charge transport layer is preferably 1% (N)≦30%, preferably 10%≦(N)530%. In addition, the charge blocking layer 44 may be made of elements of Group Va of the periodic table (for example, phosphorus), if necessary, to sufficiently prevent hole injection from the substrate 41 and to improve sensitivity and charging ability.
is doped by glow discharge decomposition to make it intrinsic, and further to N-type (
Furthermore, it becomes N° type). The doping amount is controlled by the composition of the blocking layer as follows. a-3iC or a-3iCO: Intrinsic BZH6/S i H< 2-20 volume f
fippmN type (N P H, +/ S i Ha
1"'1000 capacity ppIIIa-5iN or a
-3iNO: Intrinsic BzHb/S i H41~2000200
0 capacity ppN”) P H3/S i H41~20
00 The blocking layer may be a compound such as SiO, 5i02, etc. Further, the thickness of the blocking layer 44 is preferably 500 μm to 2 μm. If there are fewer than 500 people, the blocking effect will be weak.
Further, if the thickness exceeds 2 μm, the charge transport ability tends to deteriorate. The composition of blocking N44 is preferably as follows. That is, 1%<[03590%, preferably lO%≦(C)570%, and 1%
%, preferably 10% [N3570%, 0%≦

[0] 570%, preferably 0%≦ (0)530%
It is better to Note that each of the above layers needs to contain hydrogen. In particular, the hydrogen content in the charge generation layer 43 is essential to compensate for dangling bonds and improve photoconductivity and charge retention, and is preferably 10 to 30%. This content range also applies to the surface modification layer 45, blocking layer 44, and charge transport layer 42. In addition, as impurities for controlling the conductivity type, in addition to poron, AN, Ga, I nXT (I
Group IIa elements can be used. In addition to phosphorus, elements of Group Va of the periodic table, such as As and Sb, can be used for N-type formation. Next, a method for manufacturing the above-mentioned photoreceptor (for example, drum-shaped) and an apparatus therefor (glow discharge apparatus) will be explained with reference to FIG. A drum-shaped substrate 41 is set rotatably vertically in a vacuum chamber 52 of this device 51, and a heater 55 is used to rotate the substrate 41.
can be heated to a predetermined temperature from the inside. A cylindrical high frequency electrode 57 with a thin gas outlet 53 is disposed around and facing the substrate 41, and a glow discharge is generated between the electrode 57 and the substrate 41 by a high frequency power source 56. In addition, 62 in the figure is a supply source of SiH4 or a gaseous silicon compound, 63 is a supply source of hydrocarbon gas such as CHa, and 64 is a N2
65 is a supply source of oxygen compound gas such as 02, 66 is a carrier gas supply source such as Ar,
67 is an impurity gas (eg, B, Ha) supply source, and 68 is each flow meter. In this glow discharge device, first, the surface of a support, for example, an Al substrate 41, is cleaned and then placed in a vacuum chamber 52, and the gas pressure in the vacuum chamber 52 is set to 10-
"Torr" and exhaust the air, and the substrate 41
at a predetermined temperature, especially 100 to 350°C (preferably 150°C)
-300°C). Next, using a high-purity inert gas as a carrier gas, SiH or a gaseous silicon compound, CH4, N2, O□, etc. are appropriately introduced into the vacuum chamber 52, and a high-frequency power source is applied under a reaction pressure of, for example, 0.01 to 10 Torr. 56 to a high frequency voltage (e.g. 13.56 M
Hz) is applied. As a result, each of the above-mentioned reaction gases is decomposed by glow discharge between the electrode 57 and the substrate 41, and the N-type a
3iC:HSi type a-3iN:H, a-3i:H,P”
or N+ type a-3i: Hs a-3ic. : HSa-3ico : H in the above layer 44.42.
43, 47, 46, 45 on the substrate successively (i.e. corresponding to the example of FIG. 1, for example). In the above manufacturing method, the support temperature is set at 100 to 350°C in the step of forming the a-3t layer on the support, so the film quality (especially electrical properties) of the photoreceptor can be improved. . In addition, when forming the above a-3i photoreceptor photosensitive layer,
In order to compensate for dangling bonds, fluorine is introduced in the form of SiF, etc. in place of the above H or in combination with H, and a-3i:F, a-5t:H:F,
a-3iN:F, a-3tN:H:F,, a-3i
It can also be C:F, a-5iC:H:F. In this case, the amount of fluorine is preferably 0.5 to 10%. The above manufacturing method is based on the glow discharge decomposition method, but there are also sputtering methods, ion blating methods, and methods in which Si is evaporated while introducing activated or ionized hydrogen in a hydrogen discharge tube. (In particular, Japanese Patent Application Laid-Open No. 56-78413 (Patent Application No. 54-152) filed by the present applicant)
The above photoreceptor can also be manufactured by the method of No. 455). Hereinafter, the present invention will be described with reference to specific examples. An electrophotographic photoreceptor having the structure shown in FIG. 1 was prepared on a drum-shaped Al support by glow discharge decomposition. That is, first, after cleaning the surface of a support, for example, a drum-shaped A1 substrate 41 having a smooth surface, it is placed in a vacuum chamber 52 shown in FIG.
Torr, and exhaust the air, and keep the substrate 41 at a predetermined temperature, particularly 100 to 350°C (preferably 150 to 350°C).
Heat and hold at 300°C. Next, high-purity Ar gas was introduced as a carrier gas, and high-frequency power with a frequency of 13.56 Mllz was applied under a back pressure of Q, 5 Torr to perform a preliminary discharge for 10 minutes. Then, S i
A reaction gas consisting of Ha and PH was introduced, and the flow rate ratio was 1:
1: 1: (1,5Xl0-”) of (A r
+ S i Ha + CHa or NZ+PH+1)
By glow discharge decomposition of the condensation gas, the N-type a-8iC:H layer 44 and a
-3iN:H charge transport layer 42 was sequentially formed to a predetermined thickness at a deposition rate of 5 μm/hr. Continuing, PH3 and C
The supply of H, was stopped, SiH4 was decomposed by discharge, and the thickness was 5 μm.
a-3i: H layer 43 was formed. Subsequently, glow discharge decomposition is performed by changing the flow rate ratio of the impurity gas, and an intermediate layer 47 with a varying thickness is formed, and further a-3iCO:H or a-5iNO:H intermediate layer 46 and surface protective layer 45 are formed. Furthermore, the structure of the photoreceptor thus prepared was summarized as follows. (1) 0 surface modification layer: a-3iNO:H or a-3iC
○: H (2), intermediate layer: doping amount, film thickness change (see Figure 5) (
3). a-3i: H charge generation layer: film thickness -5 μm (41,
a-3iN:H charge transport layer: film thickness = 15 μm N content = 11% (51, a-3iC: H or a-3i N: H charge blocking layer: film thickness = 0.5 μm carbon content - 12% ( 6) Support: Aβ cylinder (mirror polished finish) Next, various tests were conducted using each of the above photoreceptors as shown in Figure 6. 0 applied perpendicularly to the 39th surface of the body,
A load W is applied to the 3R diamond needle 70, and the photoreceptor is moved by the motor 71.
Rotate it with and scratch it. Next, the electrophotographic copying machine U-
An image is produced using a modified B ix 1600 (manufactured by Konishiroku Photo Industry Co., Ltd.), and the scratch strength (g) of the photoreceptor is determined by the load at which white streaks appear on the image. After acclimatizing the photoreceptor in a modified electrophotographic copying machine U Bix 4500 (manufactured by Konishiroku Photo Industry Co., Ltd.) for 24 hours in an environment with a co-occurrence degree of 33°C and a relative humidity of 80%, the developer, paper, and blade were removed. After 1000 copies were made without contact with the paper, an image was printed and the degree of image blurring was determined based on the following criteria. ◎ - There is no image flow at all, and the reproducibility of 5.5 point English letters and thin lines is good. ○: 5.5 point alphabetic characters are slightly thicker. △: 5.5 point letters are crushed and difficult to read. x: 5.5 point English letters are illegible. Residual potential v, I (V) U -B ix Potential measurement using a modified 2500 machine,
Static elimination light 301 with a peak at 400nm! ux-se
The surface potential of the photoreceptor that remains after irradiation with c. A 360 SX type electrometer (manufactured by Trek) was used with a photoconductor inflow current of 200 μA and no exposure using a 2500 modified machine (manufactured by Konishi Roku Photo Industry 0 Kiku) and a 120-lead ) Surface potential measured just before development. Half E! /S (Aux-sec) Using the above device, the long wavelength component of 620 nm or more of the image exposure wavelength is sharply cut using a dichroic ink mirror (manufactured by Genshu Kogaku Co., Ltd.), and the surface potential is halved from 500 V to 250 ■. amount of exposure required for. (The exposure amount was measured using a 550-1 photometer (manufactured by EG and C)) The results are summarized in FIG. 7. These results show that if a photoreceptor is produced based on the present invention, a photoreceptor with excellent performance for electrophotography can be obtained.

[Brief explanation of drawings]

1 to 7 show embodiments of the present invention.
iC optical energy gear. Figure 3 is a graph showing the a-3iCO resistivity, Figure 4 is a schematic cross-sectional view of the glow discharge device, Figure 5 is a table showing the layer structure of each photoreceptor, Figure 6 is the scratch strength. FIG. 7 is a schematic diagram of the testing machine and a table showing the characteristics of each photoreceptor. FIG. 8 is a schematic sectional view of a conventional electrophotographic copying machine. In addition, in the reference numerals shown in the drawings, 39-------1--a-Si-based photoreceptor 41
−・・−・・−−−−−One support (substrate) 42−−−
---1.-Charge transport layer 43--1.-----Charge generation layer 44--
---Charge blocking layer 45-m----
・−・−Surface modified layer 46.47−−−−−・−・・・
・Middle class. Agent Patent Attorney Hiroshi Aisaka Figure 2 a-9it-xCx:HX Figure 3 Coal content (atomic%) Figure 6

Claims (1)

[Claims] 1. A charge blocking layer made of amorphous hydrogenated and/or fluorinated silicon containing at least one of carbon atoms, nitrogen atoms, and oxygen atoms; a charge transport layer made of fluorinated silicon; a charge generation layer made of amorphous hydrogenated and/or fluorinated silicon; doped with a group IIIa or Va element of the periodic table and amorphous hydrogenated and/or
or a first intermediate layer made of fluorinated silicon; and a second intermediate layer made of amorphous hydrogenated and/or fluorinated silicon containing at least one of carbon atoms, nitrogen atoms, and oxygen atoms; carbon atoms, nitrogen atoms; A photoreceptor comprising a surface-modified layer made of amorphous hydrogenated and/or fluorinated silicon containing more at least one of atoms and oxygen atoms than the second intermediate layer.