JPS61243460A - Photosensitive body - Google Patents

Abstract

PURPOSE:To enhance sensitivity in the visible and near IR wavelength regions and to retain acceptance potential by forming an electrostatic charge generating layer composed of the first layer made of amorphous silicon germanium hydride or the like and the second layer made of amorphous silicon or the like. CONSTITUTION:The photosensitive layer is obtained by laminating on a substrate 1 a charge blocking layer 7 made of amorphous silicon carbide or nitride hydride or fluoride (a-SiC,N:H,F) doped with an element of group IIIa or Va of the periodic table, a charge transfer layer 2 made of a-SiC,N:H,F, the charge generating layer 6 composed of the second layer 3 made of a-Si:H,F and the first layer 5 made of a-SiGe:H,F, and a surface modified layer 4 made of a- SiC,N:H,F. The presence of the first layer 5 and the second layer 3 of the layer 6 permits carriers to be generated with high sensitivity in the longer wavelength and visible wavelength regions, respectively, and accordingly, the photosensitive body to be enhanced in sensitivity and improved in charge retentivity of dark decay.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a photoreceptor, such as an electrophotographic photoreceptor.

□ Conventionally, as an electrophotographic photoreceptor, Se or As in Se,
Photoconductors doped with Te SSb or the like, photoconductors in which ZnO or CdS is dispersed in a resin binder, and the like 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 (hereinafter referred to as a-3t) as a matrix have been proposed in recent years. a-3i has a so-called dangling bond in which the bond of 5i-3i is broken, and many localized levels exist within the energy gap due to this defect. As a result, hopping conduction of thermally excited carriers occurs, resulting in low dark resistance, and photoexcited carriers are troughed to localized levels, resulting in poor photoconductivity. Therefore, the dangling bonds are filled by compensating the defects with hydrogen atoms (H) and bonding H to Si.

Such amorphous hydrogenated silicon (hereinafter referred to as a-3
It is called t:H. ) is attracting attention for its good photosensitivity, non-polluting properties, and good rigidity. However, a-3
It is known that t:H is about one order of magnitude less sensitive to light with a wavelength of 750 to 800 rv (near infrared) than to light in the visible range. Therefore, when using a semiconductor laser as a recording light source in an information end processor that electrically processes information signals and outputs them as a hard copy, a practical semiconductor laser for information recording is GaA I.
Since it is made of tAs and has an oscillation wavelength of 760 to 820ne+, a-3t:H has insufficient sensitivity and is inappropriate for this type of information recording.

In the case of a Se-based photoreceptor, although the sensitivity is higher than that of a photoreceptor made of an organic photoconductive material, the sensitivity in a long wavelength region is still insufficient to cope with an increase in processing speed.

Therefore, in order to improve the sensitivity in the long wavelength region while taking advantage of the excellent photoconductivity or photosensitivity of a-Si:H, amorphous silicon germanium hydride (hereinafter referred to as a-3iG
It is called e:H. ) may be used in the photoconductive layer. That is, a-3iGe:H has good photosensitivity in the wavelength range of 600 to 850 nm. However, conversely, with a-3iGe:H alone, the sensitivity in the visible region is a
-3i: Worse than H. Moreover, with only the a-3iGe:H layer, the dark resistance is only 10 8 to 10′ Ω −1 and the charge retention ability is poor. Moreover, a-SiGe:H has poor film adhesion or adhesion to the support (substrate), and its mechanical and thermal properties are inferior to a-3i:H, making it difficult to put it to practical use as an electrophotographic photoreceptor. There is a problem.

Recently, multifunctional devices that have a recording function using visible light as a light source (for example, functions as a normal electrophotographic copying machine) in addition to recording functions using semiconductor lasers, etc., have been attracting attention.
Neither a-3i:H nor a-3iGe:H mentioned above can satisfy such requirements.

To solve this problem, an a-3i:H layer with a sufficient thickness to retain charge was formed on the support, and an a-3iGe:H layer was further formed on this to form a two-layer structure. A photoreceptor having a charge generation layer (a layer that generates carriers in response to light irradiation) consisting of the following has been proposed.

According to this structure, the a-3i:H and a-3iGe:H layers provide good sensitivity in both the visible light and near-infrared light regions. However, this photoreceptor has several problems (particularly the following three points).

(L), a-3iGe: Since the H layer is present on the surface side, the chemical structure is weaker than that of a-3i, resulting in poor rigidity.

(2) When the a-3iGesH layer is thick, the sensitivity in the visible light region becomes insufficient. This is presumably because the presence of the a-3iGe:H layer inhibits the generation of photocarriers in the a-5t:H layer in the visible light region.

(3) When charging, unnecessary charge is easily injected from the support substrate side into the a-St:H layer (because of this, the surface potential cannot be maintained well, and the a-3i :H
The adhesion between the film and the support was also incomplete.
The purpose of the present invention is to provide excellent sensitivity in both the visible and near-infrared regions, as well as charge retention characteristics such as charging potential and dark decay, and stiffness resistance.
A photosensitive material with good mechanical strength (and excellent light fatigue resistance, stable electrical properties during repeated use, and always stable electrical and optical properties that are not easily affected by the usage environment (temperature, humidity, etc.) It's about offering your body.

20 Structure of the invention and its effects, namely, the photoreceptor according to the invention includes: 1. (a) a first layer made of amorphous hydrogenated and/or fluorinated silicon germanium; (c) a charge generation layer constituted by a laminated body of a second layer consisting of a second layer consisting of: (c) (a) a charge transport layer formed under the charge generation layer and made of 7As hydrogenated and/or fluorinated silicon carbide or silicon nitride; (d) a charge transport layer formed under the charge transport layer and made of amorphous hydrogenated and/or fluorinated silicon and/or a charge blocking layer made of fluorinated carbide or silicon nitride and doped with an element of group IIIa or group Va of the periodic table.

According to the present invention, the charge generation layer is composed of a laminate of a first layer made of amorphous hydrogenated and/or fluorinated silicon germanium and a second layer made of amorphous hydrogenated and/or fluorinated silicon. Therefore, it is possible to provide a photoreceptor that achieves both improved sensitivity in the near-infrared region due to the former and improved sensitivity in the visible region due to the latter. Moreover,
The latter can be formed above or below the former, but when formed above, a-3i is present on the surface side and the sensitivity in the visible range is significantly improved, while when formed below. However, the stiffness resistance is improved by the presence of the topmost surface-modified layer. In addition, high sensitivity can be maintained by reducing the film thickness of a-5iGe itself. For example, while taking advantage of the high sensitivity characteristics of a-3iGe:H in a relatively long wavelength range (e.g. 600 to 850 nm), it is possible to improve mechanical strength such as stable charge retention and printing durability, especially with a surface-modified layer. We have achieved high charge retention and film attachment, especially in the charge transport layer and charge blocking layer, and provide a useful photoreceptor that fully satisfies all the characteristics compared to those known so far. can do.

Further, the photoreceptor of the present invention is of a functionally separated type in which a charge generation layer and a charge transport layer are separated, and in particular, an amorphous hydrogenated and/or fluorinated carbide or silicon nitride layer is present as a blocking layer on the substrate side. Therefore, injection of carriers from the substrate can be effectively prevented, and if the dark resistance of other layers is increased by doping with impurities, the charged potential can be maintained and dark decay can be reduced. Furthermore, since the charge transport layer is also formed of a similar silicon carbide or nitride layer, the charge transport ability is good, and the presence of the amorphous silicon nitride surface modification layer on the outermost surface improves durability, stability, etc. .

The amorphous silicon nitride used in the present invention has a low coefficient of thermal expansion and high thermal conductivity compared to oxides and carbides, so it is resistant to thermal shock, and its mechanical strength and hardness do not decrease much even at high temperatures. Furthermore, it exhibits extremely high corrosion resistance against chemicals other than molten NaOH4'HF.

E, Example Hereinafter, the photoreceptor according to the present invention will be explained in detail.

For example, as shown in FIG.
Charge blocking layer 7 consisting of a-3iC:H or a
-3iN:H charge transport layer 2, a-3i:H layer 3
A charge generation layer 6 having a laminated structure consisting of an a-3iGe:H layer 5 and a surface modification layer 4 consisting of an a-3iN:H layer are sequentially laminated.

The charge blocking layer 7 greatly contributes to preventing injection of carriers from the substrate 1 and maintaining a sufficient surface potential.
For this purpose, the inclusion of Va group elements improves N-type conductivity.
Alternatively, it is important to exhibit P-type conductivity characteristics by containing a group IIIa element. Also, its thickness is 400 to 2μ
It is desirable that it be m. The charge transport layer 2 mainly has potential holding and charge transport functions, and is preferably formed to have a thickness of 10 to 30 μm.

On the other hand, the a-3iGe:H layer 5 forming the charge generation layer 6 generates charge carriers in response to light irradiation, and exhibits high sensitivity particularly in the long wavelength range of 600 to 850 nm. The thickness may be 1 μm or more. This layer 6
It is desirable that the total thickness is 2 to 10 μm. On the other hand, the a-3isH layer 3 functions as a carrier generation layer exhibiting high sensitivity in the visible light region, and is provided with a thickness of 1 μm or more.

Furthermore, the a-3iNsH layer 4 improves the surface potential characteristics of this photoreceptor, maintains the potential characteristics over a long period of time, and maintains environmental resistance (
Preventing the effects of chemical species generated by humidity, atmosphere, and corona discharge), increasing surface hardness due to improved bonding energy due to carbon content, improving mechanical strength and rigidity, and improving heat resistance when using photoreceptors. It has functions such as improving heat transfer properties (particularly adhesive transfer properties), and functions as a surface modification layer. It is important to select the thickness of this a-5iN:H layer 4 to be 400 to 5,000.

Next, each layer of the photoreceptor according to the present invention will be explained in more detail.

-ri2SiN:H1 This a-3iN:H layer 4 is formed by modifying the surface of the photoreceptor.
This is indispensable in order to make the St-based photoreceptor 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. Also, a-3i
N:H has a high surface hardness, so it has excellent abrasion resistance in processes such as development, transfer, and cleaning, and can withstand several hundred thousand printings.It also has good heat resistance, so it can be used in hot applications such as adhesive transfer. can be applied.

In order to achieve such excellent effects comprehensively, a-
It is important to select the thickness of the 3iN:H layer 4 within the above-mentioned range of 400 to 5,000. That is, if the film thickness exceeds 5,000 layers, the residual potential becomes too high and the sensitivity decreases, which may result in the loss of good characteristics as an a-5tt photoreceptor.

Furthermore, if the film thickness is less than 400, dark attenuation increases and photosensitivity decreases.

It has also been found that it is important to select the carbon composition of the a-3iN:H layer 4 in order to achieve the above-described effects. If the composition ratio is expressed as a-3t, -xNx:H, then X should be 0.1 to 0.7 (St +N
= 100 atos+ie%, the nitrogen atom content is preferably 10 atomic % to 70 atomic %).

Note that this a-3kNzH layer must contain hydrogen like other layers, and its hydrogen content is usually 1 to 1.
40 atomic%, further 10-30 atoa+ic%
It is better to

, this layer 2 has both the functions of potential retention and charge transport, has a dark resistivity of 10"Ω-1 or more, has high electric field resistance, and has a large potential retained per unit film thickness. (Moreover, since the electrons or holes injected from the photosensitive layer 6 exhibit high mobility and lifetime, charge carriers are efficiently transported to the support 1 side. Also, the size of the energy gap can be changed depending on the composition of carbon or nitrogen. Therefore, it is possible to efficiently inject charge carriers generated in response to light irradiation in the photosensitive layer 6 without creating a barrier.
-3iC:H or a-8tN:H layer 2 maintains a high surface potential at a practical level and efficiently and quickly transports charge carriers generated in photosensitive layer 6, resulting in a photoreceptor with high sensitivity and no residual potential. There is work.

In order to achieve these functions, the film thickness of layer 2 is, for example, 10 to
Desirably, the film thickness is 30 μm; if the film thickness is less than 10 pm, the surface potential necessary for development cannot be obtained;
If the thickness exceeds 0 μm, the rate of carriers generated in the charge generation layer reaching the substrate will decrease. Even if it is comparatively thin (for example, tens of microns)
m) Practical level surface potential can be obtained.

Also, this layer 2 is a-3t, -xCx:H or a-3i
When expressed as t yNy:H, 0.05≦X≦
□.

0.3.0.05≦y≦o,, a <carbon or nitrogen atom content 1 hair is Si+C (or N) −
5 to 3 when set to 100 atomic%. ) atom
ic%, more preferably 10-20aton+ic%)
If 0.05≦X and 0.05≦y, the electrical and optical properties of the layer 2 can be completely different from those of the a-3iGe:H layer 5, ox>o. , a, y>
When o, a, the charge transport ability of the layer decreases, so X≦0
．． 3, it is preferable that y≦0.3.

Further, the charge transport layer is preferably doped with an element of group IIIa of the periodic table, such as boron, in order to improve photosensitivity.

This layer 7 is used as a bronching and underlay layer,
The film thickness is preferably 400 to 2 μm. In other words, if the number is less than 400, the charge blocking effect will be small, and if the number is less than 400, the charge blocking effect will be small.
It is better to set it to Å or more. On the other hand, if the film thickness exceeds 2 μm, although the bronking effect is good, the photosensitivity of the photoreceptor as a whole becomes worse, and the film forming time becomes longer, which is disadvantageous from a cost standpoint.

The carbon or nitrogen content of this blocking layer is also the same as layer 2 <5-30 atomic%, preferably 10-20a
It is preferable to set it as tomic%.

It is known that the a-3iGe:H layer 5 exhibits high photoconductivity for near-infrared wavelength light as shown in FIG.
Compared to 3t:H, it has sufficient photosensitivity (half exposure amount (reciprocal of erg/cj), especially for light of 750 to 800 nm).
have. On the other hand, the a-3i:H layer 3 has sufficient sensitivity to visible light as shown in FIG.
When both of these layers (a-3iGe:H, a-3i:H) are laminated, a photoreceptor is obtained that exhibits a wide range of high sensitivity in both near-infrared and visible layers, as shown in Figure 2. It is possible to achieve the intended purpose. The stacking order of these two layers may be as described above, with a-3iGe:H on top and a-3i:H on bottom, or vice versa.
Even if H is on top, if the film thickness is made thin, visible light can effectively reach a-3t:H.

The thickness of the charge generation layer 6 is preferably 2 to 10 μm. If the film thickness is less than 2 μm, the irradiated light will not be absorbed efficiently and a portion will reach the underlying layer 2, resulting in a decrease in photosensitivity. Also a5ide:H and a-St:
Since the H layer itself does not need to have potential retention properties, there is no need to make it thicker than necessary for the photosensitive layer 6, and the upper limit is 1.
0 μm is sufficient. a-3iGe: H5 and a-
3i:H3 cannot absorb light sufficiently unless the thickness is 1 μm or more.

In addition, this charge generation layer (same as layer 2.4 described above) is doped with, for example, Group IIIa elements of the periodic table (B, AI, Ga, In, etc.) during film formation in order to enhance its charge retention. It is effective to increase the resistance by a-SiG
The film characteristics of the esH layer 5 vary greatly depending on film forming conditions such as substrate temperature and high frequency discharge power in the manufacturing method described below. In terms of composition, the Ge content is 0.1 to 50 at
oa+ic% (Si+Ge=100 atomic%)
It is recommended to set it to . That is, when it is less than 0.1 atomic%, the long wavelength sensitivity does not improve much, and when it is less than 50 atomic%.
Exceeding this will result in a decrease in sensitivity and the deterioration of the mechanical and thermal properties of the film. Also, a-5iGe:H and a-3t:H
About the bond between Si and H. The amount of H combined with St is preferably 1 to 40 atomic% relative to St.

When these conditions are met, a photoreceptor with a large ρD/ρ1 is obtained, which is desirable.

In the above, in order to compensate for dangling bonds, fluorine is introduced into a-3t instead of the above-mentioned H or in combination with H, and a-3iGe: Fs
a-3ide: H: F, a-St:F% a-3
It can also be t:H:F, a-3iC:F, a-8iC:H:F, etc. In this case, the amount of fluorine is 0.01~
20atomic%, 0.5~10a tolI
Iic% is even better.

An apparatus, such as a glow discharge decomposition apparatus, which can be used to manufacture photoreceptors according to the present invention will now be described with reference to FIG.

In a vacuum chamber 62 of this device 61, a drum-shaped substrate 1 is set so as to be vertically rotatable, and a heater 65 can heat the substrate 1 from the inside to a predetermined temperature. A cylindrical high-frequency electrode 67 with a gas outlet 63 is disposed around and facing the substrate 1, and a high-frequency power source 6 is connected between the substrate 1 and the cylindrical high-frequency electrode 67.
6 causes a glow discharge. In addition, 7 in the figure
2 is a source of S i Ha or a gaseous silicon compound;
73 is a supply source of nitrogen compound gas such as N2 and NH3, 74
is CH.

75 is a carrier gas supply source such as Ar, 76 is an impurity gas (e.g. BgH6 or PH
3) Supply source 77 is each flow meter. In this glow discharge device, first, the surface of the support, for example, the AI substrate 1, is cleaned, and then placed in a vacuum chamber 62, and the gas pressure in the vacuum chamber 62 is adjusted to 10-' Torr, and the air is evacuated. and keep the substrate 1 at a predetermined temperature, particularly 100 to 350°C (
Preferably, the temperature is maintained at a temperature of 150 to 300°C. Next, using a high purity inert gas as a carrier gas, Si
Ha or gaseous silicon compound, GeH or gaseous germanium compound, B*Hh (or P)13),
CH, or N3 is appropriately introduced into the vacuum chamber 62, and a high frequency voltage (for example, 13.56 MHz) is applied by the high frequency power supply 66 under a reaction pressure of, for example, 0.01 to 10 Torr. This allows each of the reaction gases to be transferred between the electrode 67 and the substrate 1.
Glow discharge decomposes between boron or phosphorous doped a
-3iC: H1 boron doped a-stc: H, boron doped a-5t: Hs boron doped a-3iG
e:HSa-3iN:H in the above layer 7.2.3.5.4
(i.e., corresponding to the example of FIG. 1) on the substrate.

When forming each layer by glow discharge decomposition in this way, it is necessary to appropriately select the flow rate ratio of diborane or phosphine gas and silicon compound (for example, monosilane). When forming a negatively charged photoreceptor, when forming the a-3iC:H charge blocking layer 7, PH3 (phosphine) and Si
When the flow rate ratio with gn (monosilane) is changed, as a result of phosphorous doping with PH3, the blocking layer can sufficiently prevent carrier injection from the substrate in the region where N-type conductivity is stabilized. PH.

/5iHa (D flow rate ratio is preferably 1 to 1000 ppm by volume. This ratio is preferably from 1 to 10 ppm by volume for an a-3iN:H charge blocking layer.

In addition, in the case of P-type for positive charging by boron doping, B
z H&/S i Ha -20 to 5000 capacity ppa+ (a-3i C: H(F) and Ki), 10
It is preferable to perform glow discharge decomposition with a capacity of 3 to 10 ppa+ (when a-3iN:H).

On the other hand, the amount of boron doping performed during the formation of layer 2.6 needs to be appropriately selected in order to obtain the desired dark resistance value. 5iHa = 1-20 capacity ppm
(When a-3iC:H), 1 to 1000 capacity pps+
(at the time of a-3iN:H), and in the layer 6, BlHi/S i Ha may be set to 0.1 to 10 ppm by volume. The doping amount may be different between layers 5 and 3. Also, the surface modified layer 4 is similarly doped with boron.
It can also be done with a capacitance ppn+.

However, since the optimum range of the impurity doping amount described above depends on the N, C, and H contents of the layer, it is not necessarily limited to the above range.

Although the above manufacturing method is based on a glow discharge decomposition method, the photoreceptor can also be manufactured by a vapor deposition method, a sputtering method, an ion blating method, or the like. The reaction gas used is SiH.

In addition, lower hydrocarbon gases such as SigHa, 5iHFs, 5iFs or derivative gases thereof, and CxHb and CsHm other than CH can be used. Further, as impurities to be doped, in addition to the above-mentioned boron and aluminum, other elements of group 1a of the periodic table such as gallium and indium, and other elements of group Va of the periodic table such as arsenic and antimony other than phosphorus can be used.

Figure 1 was deposited on an AIl support by glow discharge decomposition method.
=゛Next, an example in which the present invention is applied to an electrophotographic photoreceptor will be specifically explained.

An electrophotographic photoreceptor with the structure was fabricated. first smooth
, :Clean AJ with surface! The support was placed in a reaction (vacuum) chamber of a glow discharge device. After evacuating the inside of the reaction tank to a high vacuum level of 10-' Torr and heating the support to 200°C, high-purity Ar gas was introduced, and under a pre-pressure of Q, 5 Torr, a frequency of 1 was applied.
A high frequency power of 3.56 MHz and a power density of 0.04 W/c11 was applied, and a preliminary discharge was performed for 15 minutes.Next, a reaction gas consisting of SiHa and CHa was introduced at a flow rate ratio of 3:1:0. 5 to 0.05 (Ar+S i
By glow discharge decomposition of Hn + CHa') mixed gas and PH or BtHh gas, 1,000 people created an a-3iCsH layer that prevents carrier injection, and an a-3iC:H layer that has potential holding and charge transport functions. The film was formed at a deposition rate of hL. After the reaction tank is once evacuated, SiH and/or GeH, B, and H are discharge decomposed using Ar as a carrier gas without supplying CH4, and boron-doped a
-3t:H and a-SiGe:H photosensitive layers were formed (a
-3i sH layer Ar: SiHa = 5:
1, a-3iGe: In the H layer, Ar: Si H4
: GeH4=25:4:1). After that, N was supplied, and then (Ar + S) was supplied at a flow rate ratio of 5:1:4 to 0.5.
i Ha +Na) mixed gas and B z Hh were decomposed by glow discharge, and an a-3iN:H surface modification layer was further provided to complete an electrophotographic photoreceptor. The optical energy gap of this a-3iN:H surface modification layer is 2.5-2. OeV
Met. In addition, the nitrogen composition is 40 to 60 atomic%.
Analysis revealed that.

Regarding such a photoreceptor, the composition of each layer was changed as shown in FIG. 4, and the following measurements were carried out.

Charging potential Vo (V): photoreceptor inflow current 200 μA,
The surface potential of the photoreceptor immediately before development was measured with a 360 SX type potential needle (manufactured by Toresok Co., Ltd.) under the condition of no exposure.

Half-decreased exposure amount: dual intensity 1μW/cd, wavelength 750nm
Exposure amount required to halve the surface voltage from 500 V to 250 V by light irradiation of E% (erg/cffl).

Residual potential V, (V): Surface potential after exposure and irradiation with 30 II ux-sec of photostatic discharge light having a peak at 400 na+.

Image quality: 10. After forming an electrostatic latent image by exposing it to crW/aJ at a wavelength of 750 nm, it was developed with a two-component magnetic brush using negative or positive toner depending on the charge polarity, and when it was transferred and fixed on transfer paper, the image I was able to obtain clear images with high density and no capri. The image quality of copies after repeated copying operations were performed 200,000 times was determined.

◎ Image density is sufficiently high and resolution Clear, with good contrast and gradation. There are white streaks and white spots on the image. do not have. In other words, the image is very good. Good.

○ Good image.

Δ Can be used for practical purposes.

×　Image cannot be used for practical purposes.

As shown in FIG. 4, the photoreceptor according to the present invention had a small amount of half-decreased exposure during exposure, had a small residual potential, and had very good charging/exposure repetition characteristics.

[Brief explanation of drawings]

The drawings illustrate the present invention; FIG. 1 is a cross-sectional view of a portion of an electrophotographic photoreceptor, FIG. 2 is a graph showing the photosensitivity of each photoreceptor depending on the wavelength of light, and FIG. 3 is a graph showing the photosensitivity of each photoreceptor according to the wavelength of light. FIG. 4 is a schematic cross-sectional view of a glow discharge apparatus for manufacturing the electrophotographic photoreceptor. In addition, in the symbols shown in the drawings, 1 ----
---1...Support (substrate) 2--Charge transport layer 3----------a-3i: H layer 4-111-
-Surface modified layer 5-------a -S i Ge: H layer 6
---Charge generation layer 7 ---Charge blocking layer.

Claims (1)

[Claims] 1 (a) Consisting of a laminate of a first layer made of amorphous hydrogenated and/or fluorinated silicon germanium and a second layer made of amorphous hydrogenated and/or fluorinated silicon (b) a surface modification layer formed on the charge generation layer and made of amorphous hydrogenated and/or fluorinated silicon nitride; (c) a surface modification layer formed under the charge generation layer and made of amorphous silicon nitride; (d) a charge transport layer formed below the charge transport layer and consisting of an amorphous hydrogenated and/or fluorinated silicon carbide or nitride and comprising a hydrogenated and/or fluorinated silicon carbide or nitride; A photoreceptor comprising a charge blocking layer doped with a group IIIa or group Va element.