JPS59212841A - Photosensitive body - Google Patents

Abstract

PURPOSE:To permit a thin film to retain high potential by forming a photosensitive body composed of an a(amorphous)-SiN type surface-modified layer and an a-Si type photoconductive layer and an a-SiC type electrostatic charge transfer layer. CONSTITUTION:A charge transfer layer 2 made of a-SiC hydride or fluoride contg. 10-30atomic% C is formed on a substrate 1. On this layer 2, a photoconductive layer 3 made of a-Si hydride or fluoride is formed. Further on this layer 3, a surface-modified layer 4 made of a-SiN hydride or fluoride is formed. It is desirable to form a charge blocking layer made of a-SiC hydride or fluoride doped with an element of group VA of the periodic table between the layer 2 and the substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoreceptor, and particularly to an electrophotographic photoreceptor suitable for use with negative charging.

2. Prior art Conventionally, as an electrophotographic photoreceptor, Se, or Se and As,
Photoreceptor doped with Te, Sb, etc., ZnO or CdS
Photoreceptors, etc., in which the compound is dispersed in a resin binder are known. However, these photoreceptors have problems in terms of environmental pollution, thermal stability, and PA mechanical strength.

On the other hand, electrophotographic photoreceptors using amorphous silicon (a-8t) as a matrix have been proposed in recent years.

a-81 has a so-called dangling bond in which the 5i-8i bond is broken, and many localized levels exist within the energy gap due to this defect.
For this reason, hopping 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, the dangling bonds are filled by compensating the above defects with hydrogen atoms (H) and forming H bonds to Si.

Such amorphous hydrogenated silicon (hereinafter referred to as a-8
It is called i:H. ) has a resistivity of 188 to 109 in the dark.
It is about 1/10,000 times lower than amorphous Se. Therefore, a photoreceptor made of a single layer of a-8l:H has problems in that the dark decay rate of the surface potential is high and the initial charging potential is low. But on the other hand,
When irradiated with light in the visible and infrared regions, the resistivity decreases significantly, so it has extremely excellent properties as a photosensitive layer of a photoreceptor.

Therefore, in order to impart potential holding ability to such a-81:H, the resistivity was increased to 10 by doping with boron, etc.
1! However, it is not easy to control the amount of boron etc. accurately. In addition, by introducing a trace amount of oxygen together with boron etc.
Although it is possible to increase the resistance to about 1 ohm-ohm, when this is used in a photoreceptor, the photosensitivity decreases, causing problems such as worsening of edge breakage and generation of residual potential.

In addition, a photoreceptor with a surface made of %a-8t:H is subject to chemical stability on the surface, such as the effects of long-term exposure to the atmosphere or moisture, and the effects of chemical species generated by copious discharge. Until now, sufficient consideration has not been made regarding gender. For example, it is known that those that have been left unused for more than a month are affected by humidity and their receptive potential drops significantly. On the other hand, regarding amorphous hydrogenated silicon carbide (hereinafter referred to as a-8iC:H), its manufacturing method and existence are 'Ph1l,
Mag, Vol. 35" (1978), etc., and its characteristics include high heat resistance and surface hardness.
a-8i: High dark resistivity (1011~1
It is known that the optical energy gap changes over a range of 1.6 to 2.8 oV depending on the amount of carbon. However, there is a drawback that the long wavelength sensitivity becomes poor due to the widening of the band gap due to the inclusion of carbon.

An electrophotographic photoreceptor combining a-8iC:H and a-3i:H has been proposed in, for example, Japanese Patent Laid-Open No. 127083/1983. According to this, a-81
: The H layer is a photosensitive (Koudoisha) layer, and the a-
8iC: Functional separator 2 with H layer as a charge transport layer
By creating a layered structure, the upper layer a-3i:HK obtains photosensitivity in a wider wavelength range, and the lower layer a-8iC:H, which forms a heterojunction with the a-3MH layer, improves the band potential. We are trying to However, it is not possible to sufficiently prevent the darkening of the a-8l:H layer, and the charge level is still insufficient, making it impractical, and the a-8t:H layer is present on one surface. chemical stability and mechanical strength,
Heat resistance etc. become poor. Moreover, the carbon atom content of the charge transport layer has not been studied, and the thickness of each layer has not been considered, so it does not satisfy the various properties required for an electrophotographic photoreceptor. Not yet.

On the other hand, JP-A-57-17952 discloses a-8i:
A first a-8iC:H layer is formed as a surface modification layer on the photoconductive layer consisting of H, and a second a-8IC:H layer is formed on the back surface (support electrode side) as a charge transport layer. As a result, the photoreceptor has a functionally separated three-layer structure. Although this known photoreceptor has the effect of preventing dark decay of the a-81:H layer, no study has been made regarding the carbon atom content of the a-8le:H layer, especially the charge transport layer. , a-8t
: Sensitivity decreases depending on the bonding state with the H layer, residual potential also increases, and it does not have the durability to withstand multiple copies.

3. Purpose of the Invention The present inventor has made extensive studies on the problems of the prior art as described above, and has devised a photoreceptor with a novel structure that has the features of a functionally separated photoreceptor such as the three-layer structure described above. In particular, we discovered that the carbon atom content of the charge transport layer greatly affects the characteristics of the photoreceptor, and by setting the carbon atom content within an appropriate range, we were able to achieve excellent photosensitivity, residual potential, durability, etc. We succeeded in obtaining a photoreceptor.

4. Structure of the Invention That is, the present invention includes a photoconductive layer made of amorphous hydrogenated and/or fluorinated silicon (e.g. a-81:H), and a photoconductive layer formed on the photoconductive layer and made of amorphous hydrogenated and/or fluorinated silicon. Fluorinated silicon (e.g. a-8IN:H
), and a charge transport layer formed under the photoconductive layer and made of amorphous hydrogenated and/or fluorinated silicon carbide (e.g. a-81C:H), the charge transport layer comprising: carbon atom content of 10 to 30 at
The present invention relates to a photoreceptor characterized by being omic '16.

5. Examples Hereinafter, the photoreceptor according to the present invention will be explained in detail.

The photoreceptor according to the present invention has a Vca-8IC:H layer (charge transport layer) 2 on a conductive support substrate 1, as shown in FIG. 1, for example.
, a-8i:HJii (photoconductive layer) 3 , a-
It consists of 8IN:H layers (surface modified layers) 4 laminated in sequence. a-8IC: The H layer 2 mainly has the functions of maintaining potential, transporting charges, and improving adhesion to the substrate 1, and its carbon atom content is 10 to 30 ato.
-mie % (ratio of St and C to the total number of atoms) is essential, and 108 m
It is preferably formed to have a thickness of ~30 μm. Photoconductive layer 3
generates charge carriers in response to light irradiation, and its thickness is preferably 2500X to 5 μm. Furthermore, the a-8iN:H layer 4 improves the surface potential characteristics of this photoreceptor, maintains the potential characteristics over a long period of time, and maintains environmental resistance (prevents the influence of humidity, atmosphere, and chemical species generated by corona discharge). It has the functions of improving printing durability due to its high surface hardness, improving heat resistance when using a photoreceptor, and improving thermal transferability (especially adhesive transferability), and acts as a surface modification layer. . And this a-8iN:H layer 4
The thickness t is 400X to 5000X, especially 400X≦
It is important to make it much thinner than the conventional one, with t<2000 X.

By configuring the photoreceptor in this way, the conventional Se
Compared to photoreceptors, it maintains a high potential with a thin film thickness, exhibits excellent sensitivity to light in the visible and infrared regions, has good heat resistance and printing durability, and has stable environmental resistance. a-8
Therefore, it is possible to provide an L-based photoreceptor (for example, for electrophotography).

Moreover, what is noteworthy is that by setting the carbon atom content of the charge transport layer within a specific range of 10 to 30 atomic%, the photoreceptor has more than enough of the various properties required. It is.

This will be explained in detail below.

First, it has been confirmed that the optical energy gap (ELJ, opt) of a-8IC:H generally increases as the carbon atom content increases, as shown in Figure 2. This E2 corresponds to the band gap, and if the carbon atom content is increased, then a
It can be seen that the difference from Ey (approximately 1.71 eV) of -81:H becomes large.

On the other hand, the carbon atom content is a-81C as shown in Figure 3.
:H's specific resistance, (ρD: dark resistivity, ρ.: resistivity when irradiated with green light), and if the carbon content (i.e., town) is increased, the photosensitivity (pD/ρ) will change over a certain range.

) decreases, as shown in Figure 4. When the wavelength of the irradiated light is changed, the photosensitivity of a-8iC:H changes depending on the carbon content, as shown in FIG.

FIG. 6 shows the energy band of the photoreceptor having the layer structure described in FIG. In this energy band diagram, as described above, the carbon atom content of the charge transport layer 2 is 10 to 10% (15% in the illustrated example).
Atomic %: Eta = 2.1 eV)
Because it is set to K! The cargo transport layer 2 itself has an appropriate size, and the a-81:H layer 3 has Eg(
1.71 eV) forms a band gap that does not substantially form a barrier to electrons.

That is, when the surface of this photoreceptor is operated with a negative charge, holes indicated by the 0 mark are about to be injected from the base 1 side, but these holes are in the bounce band Ev of the a-8iC:H layer 2. unable to overcome the energy barrier,
As a result, negative charges on the surface of the photoreceptor are sufficiently retained, dark decay is reduced, and potential retention ability is improved. Furthermore, among the carriers (holes marked with ○, electrons shown with marks) generated in the photoconductive layer 3 during light irradiation, the conduction band Ec of the electrons is almost a barrier between the layers 2 and 3. (i.e., energy level matching is good), holes can easily move to the substrate l side via the a-8IC:H layer 2, and holes can easily move to the surface side via the thin surface layer 4. It moves to selectively neutralize surface charges and efficiently form an electrostatic latent image.

Therefore, this photoreceptor has good photosensitivity in addition to the above-mentioned potential holding ability.

In order to obtain these remarkable effects, especially the charge transport layer 2
The present inventors clearly pointed out for the first time that the carbon atom content of io to 30 atomic % must be specified. That is, the carbon atom content is 10 a
If it is less than tomic %, the specific resistance of the a-8iC:H layer 2 is less than 1OIRQ-1 required for potential holding ability (see FIG. 3), and the charging potential becomes insufficient, which is unsuitable. Furthermore, when the carbon atom content exceeds 30 atomic %, the resistivity decreases as well, and at the same time, the presence of too many carbon atoms increases defects in the a-8iC:H layer, resulting in poor carrier transport ability itself. .

It is also important that in the above-mentioned photoreceptor according to the present invention, the photoconductive layer 3 is not doped with any impurities such as group ff1A of the periodic table. In other words, as in the prior art,
-81: Doping the H layer with impurities to increase its resistance (
When aiming for ρo ""10" ~ 10uΩ-cIrL), the carrier range (μτ) of electrons, that is, (mobility x lifetime), decreases due to impurity doping, and this causes the optical attenuation curve to tail, resulting in a decrease in sensitivity. This may cause a decrease in image quality.

FIG. 7 shows the optical attenuation characteristics of the above-mentioned photoreceptor in which the photoconductive layer 3 is not doped with impurities. It has been found that when doped with (for example, CBt Ha )/(S iL )-20 in the Goo-discharge method described later, the attenuation curve becomes tailed during light irradiation.

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

This a-8IN:H layer 4 is formed by modifying the surface of the photoreceptor.
This is indispensable for making the 8i photoreceptor practically superior. That is, it enables the basic operations of an electrophotographic photoreceptor, such as charge retention on one surface and attenuation of the surface potential by 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-81: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 a-8IN:H has a high surface hardness, it
Has abrasion resistance during processes such as transfer and cleaning,
Furthermore, since it has good heat resistance, it is possible to apply heat-applying processes such as adhesive transfer.

In order to achieve such excellent effects comprehensively, a-
8IN: The thickness of the H layer 4 is 400X≦t<500 as described above.
It is extremely important to select within the range of 0 K (especially 400 X≦t<zoooX). That is, when the film thickness is 5000X or more, as shown in FIG.
The residual potential v8 becomes too high and the sensitivity E3A (described later) also decreases, and the good characteristics as an a-8i photoreceptor are lost. In addition, if the film thickness is less than 400X, the charge will not be charged on the surface due to the tunnel effect, so dark decay (especially less than 2000X), 4oo
Although it is desirable that the thickness be X or more, such a thickness range cannot be expected at all from conventionally known techniques.

Furthermore, this a-8iN:H layer 4 exhibits characteristics similar to those of the a-8IC:H shown in Figs. 2 to 5, and its nitrogen composition is selected in order to achieve the above-mentioned effects. It turns out that it is also important to.

If the composition ratio is expressed as a-811-xNx:H, then X is 0.
．． 1 to 0.7 (nitrogen atom content is 10ato
It is desirable that the mic is between 70 and 70 atomic 9J). That is.

If 0.1≦X, the optical energy gap is approximately 2. OeV or more, the irradiated light is a-8i:H due to the so-called optically transparent window effect for visible and infrared light.
The layer (charge generation layer) 31C is reached.

Conversely, when x < 0.1, a portion of the light is absorbed by the surface layer 4, and the photosensitivity of the photoreceptor tends to decrease.

Moreover, when X exceeds 067, most of the layer becomes nitrogen,
In addition to the loss of semiconductor properties, the deposition rate when forming an a-8iN:H film using glue discharge properties decreases, so if X≦
It is better to set it to 0.7.

a-8iC:H layer (charge transport layer) This a-8iC:H layer 2 has both the functions of potential retention and charge transport, has a dark resistivity of 10'''Ω-α or more, and has high electric field resistance. The potential held per unit film thickness is high, and the electrons injected from the photosensitive layer 3 exhibit large mobility and lifetime, so charge carriers are efficiently transported to the support l side. , composition of carbon (10-30 atomic
% ) IC can adjust the size of the energy gap, so that electrons generated in the photosensitive layer 3 in response to light irradiation can be efficiently injected without creating a barrier.

Furthermore, since a barrier is formed to prevent the injection of holes from the substrate l side, it has an extremely excellent ability to hold a charged potential. This second a-8iC:H layer 2 is also a support 1, for example AI! It also has properties such as good adhesion to electrodes and good film formation.

Therefore, this a-8iC:H layer 2 maintains a high surface potential at a practical level, efficiently and rapidly transports the charge carriers generated in the a-81:H layer 3, and forms a photoreceptor with high sensitivity and no residual potential. There is a function to do that.

In order to achieve such a function, the film thickness of the a-8iC:H layer 2 is preferably 10 μm to 30 μm in order to apply a dry development method using, for example, a curling method.
If the film thickness is less than 10 μm, it is too thin and the surface potential necessary for development cannot be obtained, and if it exceeds 30 μm, the rate at which the carrier reaches the support 1 decreases. However,
Even if the film thickness of the a-8iC:H layer is made thinner (for example, 10-odd μm) than that of the Se photoreceptor, a surface potential at a practical level can be obtained.

a-8i: H layer (14 electrical layers or photosensitive layers) this a-8i:
The H layer 3 has high photoconductivity to visible light and infrared light, and as shown in FIG. L length 650
For red light in the vicinity of nm, ρD/ρ becomes the maximum ~1o4. By using this a-8i:H as a photosensitive layer, it is possible to create a photoreceptor that is highly sensitive to light in the entire visible region and in the infrared region.

In order to absorb visible light and infrared light without waste and generate charge carriers in this way, it is desirable that the film thickness of a-8MHiff13 be 25001 to 5 μm.

To reach this point, the light sensitivity is significantly reduced. Also, a-
8i: Hji #3 has a large charge transport ability.

Since the resistivity is ~10'Ω-1 and it does not have potential retention property as such, there is no need to make the photosensitive layer thicker than necessary for light absorption, and the film thickness is at most 5μ.
If m is the era name. Furthermore, if the thickness exceeds 5 μm, carriers tend to diffuse laterally in the layer, resulting in a decrease in sensitivity.

Next, a device (glue discharge device) that can be used to manufacture a photoreceptor according to the present invention will be described with reference to FIG. 1θ.

In the vacuum chamber 12 of this apparatus 11, the above-mentioned substrate l is fixed on the substrate holding part 14, and the substrate l can be heated to a predetermined temperature by a heater 15. A high-frequency electrode 17 is arranged opposite to the substrate 1, and a glue discharge is generated between the high-frequency electrode 17 and the substrate 1.

In addition, 20.21.22, 23.24.25.2 in Figure 1
7.28, 29.30.35.36.38.39 are each pulp, 31 is SIH or a source of gaseous silicon compound, 32 is CH or source of gaseous carbon compound, 33
is a carrier gas supply source such as Ar or H, 34 is N or a gaseous nitrogen compound supply source, and 37 is a 5IF4 gas supply source (fluorine supply source). In this glow discharge device, first, after cleaning the surface of a support, for example, an Al substrate l, it is placed in a vacuum chamber 12, and the cleaning valve 36 is adjusted so that the gas pressure in the vacuum chamber 12 becomes 10-'Torr. and evacuate the air, and bring the substrate l to a predetermined temperature.

For example, it is heated and maintained at 200°C. Next, a mixed gas prepared by diluting an appropriate amount of 5IN (4 or a gaseous silicon compound, and CH4 or a gaseous carbon compound, or N2 or a gaseous nitrogen compound) is placed in the vacuum chamber 12 using a high-purity inert gas as a carrier gas. Introduced, 0.01~10Torr
High frequency power is applied by the high frequency power supply 16 under the reaction pressure of . As a result, each of the above reaction gases is decomposed by glue discharge, and a-8IC:H containing hydrogen is deposited on the substrate 1 as the above layer 2, and further a-SIN:H containing hydrogen is deposited as the above layer 4. . At this time, the desired composition ratio and optical energy gap can be achieved by appropriately adjusting the flow rate ratio of the silicon compound and the carbon compound or the nitrogen compound and the substrate temperature. : a St at a speed of xoooX/=+ or more without affecting the electrical characteristics of H
It is possible to deposit C:H or a-8iN:H.

Further, in order to deposit a-8i:H (photosensitive layer 3 described above), the silicon compound may be decomposed by glue discharge without supplying a carbon compound or a silicon compound.

Both the above a-8IC:H layer and a-8iN:H layer,
Although it is necessary to contain hydrogen, if hydrogen is not contained, the charge retention characteristics of the photoreceptor will not be practical. Therefore, the hydrogen content is 10-30
It is desirable to set it to atomic%.

If it is less than 10 atomic%, compensation for dangling bonds is insufficient, and if it exceeds 30 atomic%, defects are more likely to occur.

The hydrogen content in the photoconductive layer 3 is essential to compensate for dangling bonds and improve photoconductivity and charge retention, and is usually 10 to 3° atomic%. Desirable for similar reasons.

In addition, in order to compensate for dangling bonds, a −
For S1, fluorine is introduced instead of the above-mentioned H or in combination with H (supply source is SIF) a-8
1:F%a-8i:H:F, a-81C:F, a
-8iC:H:F% a-8IN:F, a-8iN:H
:F can also be used. In this case, the amount of fluorine is 0
．． 5 to 10 atom-ie% is desirable.

The above manufacturing method is based on the glue discharge decomposition method, but other methods include sputtering method, ion jinging method, and hydrogen activated or ionized with water or a. -81 vapor deposition method (PR includes Japanese Patent Application Laid-Open No. 56-78413 (Patent Application
4-152455), θmi), etc., the above-mentioned photoreceptor can also be manufactured.

In addition to SiH4 and SiF4, the Minshin gases used are St,
H6,5iHF5 or its derivative scum, other than CH, ('
) Lower hydrocarbon gases such as CI Ha and C5Ha and CF can be used.

Next, an example in which the present invention is applied to an electrophotographic photoreceptor will be specifically described.

An electrophotographic photoreceptor having the structure shown in FIG. 1 was prepared on an Al support by a glue discharge decomposition method. First, a clean AJ support with a smooth surface was placed in a reaction (vacuum) chamber of a glue discharge device. After evacuating the reaction chamber to a high vacuum level of 10-6 Torr and heating the support to 200°C, high purity A was obtained.
r gas was introduced, and high frequency power with a frequency of 13.56 eyes and a power density of 0.04 W/cnl was applied under a back pressure of 0.5 Torr, and a preliminary discharge was performed for 15 minutes. Next, a reactive gas consisting of 5IH4 and CH4 was introduced, and the flow rate ratio was adjusted (Ar + SIL + CH4). By decomposing the mixed gas by glue discharge, the a-8IC:H layer, which plays the role of potential retention and charge transport, was heated to 350X/= The film was formed to a predetermined thickness at a deposition rate of . % after evacuating the reaction tank once
CL was not supplied, and 5IH4 was discharge decomposed as an Ar carrier gas to form an a-81:H photosensitive layer of a predetermined thickness, and then H8 was supplied and the flow rate ratio was adjusted (Ar + S I
n2 + Nt) mixed gas was decomposed by glue discharge, and a surface-modified layer having a predetermined thickness of a-8IN:H was further provided to complete an electrophotographic photoreceptor.

The thus produced photoreceptor was subjected to a negative polarity 6 kV Cop discharge, and various electrophotographic characteristics were measured. In this case, when samples (sample rk 1-11!127) were prepared in which the composition and film thickness of each layer of the photoreceptor were varied, results as shown in Fig. M11 were obtained.

In this test, the electrophotographic photoreceptor prepared as described above was placed in an entrometer model 5P-428 (manufactured by Kawaguchi Electric Co., Ltd.), and the voltage applied to the discharge electrode of the charger was -6 kV for 10 seconds. A charging operation is performed, and the charging potential of the photoreceptor surface immediately after this charging operation Vo (V
), and after 5 seconds of dark decay, the amount of irradiation light required to attenuate the charged potential to y6 is halved by the exposure amount E 'A (1
ux-sea). The light attenuation curve of the surface potential becomes flat at a certain finite potential, and may not completely reach zero, but this potential is called a residual potential Vm (v). Regarding image quality, the photoreceptor was made into a drum shape, and the electrophotographic copying machine U-BlxV was used at 20°C and 604RH.
(Konishi Roku Photo Industry Co., Ltd. 5M), print the picture, and (Initial image quality (LOO)).

The image quality (image quality after one copy) and the image quality after multiple uses (image quality after 200,000 copies) were evaluated as follows.

Image density 1.0 or more ◎ (Very good image quality)〃0
．． 6-1.0 0 (Good image quality)〃Less than 0.6△ (
(blurring occurs in the image) x (density is extremely low and cannot be distinguished) As is clear from the data shown in the table of Figure 11, sample 11 without a surface modification layer! It can be seen that the sample tooth 2 of the present invention, which has a three-layer structure provided with a surface modification layer, exhibits superior characteristics compared to llK. Furthermore, as is clear from sample rk19423, the carbon atom content of the charge transport layer was adjusted to lθ~30 at
By specifying om1c% (indicated simply as "%" in the table), it is possible to significantly improve the durability when copying a large number of sheets while maintaining the photosensitivity and residual potential at good values. Furthermore, it can be seen that it is important to set the composition, thickness, etc. of each layer within the above-mentioned desirable ranges.

FIG. 12 shows a photoreceptor according to another embodiment of the present invention, in which a charge boot king layer 5 ( For example, phosphorus-doped a-8iC:H, a-8iC:F.

a-8IC:H:F) is added.

When the blocking layer 5 is composed of a-8iC,
Its carbon atom content is 10-30 atomic%,
Hydrogen atom content is 10 to 30 atomlc% When containing fluorine atoms, fluorine atom content is 0.5 to 10
It is an atomic type, and is made into an N-type by doping with a Group VA element of the periodic table as an impurity.

For impurity doping, an impurity supply source, for example, PH, is added to the apparatus t in FIG.
Each reaction gas may be supplied at a flow rate of a)/(S iL )≦2000. Note that the thickness of the charge blocking layer 5 is preferably 4001 to 1 μm.

By providing the blocking layer 5, the energy bands of each layer of the photoreceptor become as shown in FIG. 13, and a larger energy barrier than that shown in FIG. 6 is formed at the interface with the substrate 1. Therefore, the injection of holes from the substrate 1 can be sufficiently prevented.

As is clear from the boots of samples 1'1k28 to 30 in FIG.
It has been suggested that if tL) is made too large, the characteristics deteriorate, and that there is an appropriate range for the thickness of the blocking layer. (PHs) / CSiL) is 20
00 pIm or less, the thickness of the blocking layer is 1 μm or less,
It is desirable to set it to 400X or more.

61 Effects of the Invention As described above, the present invention comprises a photoreceptor made of a laminate of an a-8IN-based surface-modified layer, an a-Si-based photoconductive layer, and an a-8iC-based charge transport layer. Because of its thin film thickness, it maintains a high potential, exhibits excellent sensitivity to light in the visible and infrared regions, has good heat resistance and printing durability, and has stable environmental resistance. A photoreceptor (for example, for electrophotography) can be provided.

What is noteworthy is that by setting the carbon atom content of the charge transport layer in a specific range of 10 to 30 atomic%, various properties required for photoreceptors (especially high sensitivity,
It has sufficient characteristics (low residual potential, high potential holding ability, and repeated durability).

[Brief explanation of drawings]

The drawings illustrate the invention. Fig. 1 is a cross-sectional view of a part of an electrophotographic photoreceptor, Fig. 2 is a graph showing changes in the optical energy gap of a-SiC:H depending on the carbon atom content, and Fig. 3 is a graph showing changes in the optical energy gap of a-SiC:H depending on the carbon atom content. A graph showing the change in specific resistance of -8iC:H, Figure 4 shows a due to the optical energy gap.
A graph showing the photosensitivity characteristics of -8iC:H. FIG. 5 is a graph showing a comparison of the photosensitivity characteristics depending on the wavelength of irradiated light. Figure 6 is an energy band diagram of each layer of the photoreceptor, Figure 7 is a potential attenuation characteristic diagram of the photoreceptor, Figure 8 is a potential attenuation characteristic diagram of a photoreceptor according to a comparative example, and Figure 9 is the thickness of the surface modified layer. FIG. 10 is a schematic cross-sectional view of a photoreceptor manufacturing apparatus, FIG. 11 is a diagram showing the characteristics of various photoreceptors, and FIG. 12 is a graph showing a portion of a photoreceptor according to another example. 13 is an energy band diagram of each layer of the photoreceptor shown in FIG. 12. In addition, in the symbols shown in the drawings, 1...
...Support (substrate) 2 ... ... a-
8IC:H layer (charge transport layer) 3...
a-8i: H photosensitive layer (photoconductive layer) 4...
・a-8iN: H layer (surface modified layer) 5...
・Charge boot king layer 11 ・Glue discharge device 17 ・High frequency electrode 31 ・Gaseous silicon compound supply source 32 ...... Gaseous carbon compound supply source 33.
......Carrier gas supply source 34...
... Gaseous yano compound supply source 37 ...
5IF4 gas supply source E), apt...Optical energy gap ρD/ρ0...Dark resistivity/Resistivity during light irradiation E%...Half-decreased exposure amount ■R ......Residual potential. No. 91 Swamp Wet h (μm) Figure 13 (Spontaneous) Procedure Right n Ordinary Book 1, Indication of the Case 1988 Patent Side beam No. 86892 2, Name of the invention Photoconductor 3, Person making the amendment Relationship with the case Patent Applicant Address 1-26-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo Name
(], 27) Konishiroku Photo Industry Co., Ltd. 6-4, Agent address: 6, 2nd floor, Suzuki Hill, 3-9-17 Shibasaki-cho, Tachikawa-shi, Tokyo, Number of inventions increased by amendment 7, Specification subject to amendment Detailed explanation of the invention column 8, content of amendment +11, 118 on the 5th line from the bottom of the 4th specification is changed to 10
” I am corrected. (2), on page 10, line 9, ``1 vs. environment'' is corrected to ``environmental resistance.'' (3), page 24, line 6, "15 seconds" was corrected to "2 seconds". One or more - 335-

Claims (1)

[Claims] 1. A photoconductive layer made of amorphous hydrogenated and/or fluorinated silicon, and a photoconductive layer formed on this photoconductive layer and made of 7 mol 7 As hydrogenated and/or fluorinated silicon nitride ρ. and a charge transport layer formed under the photoconductive layer and made of amorphous hydrogenated and/or fluorinated silicon carbide, the charge transport layer having a carbon atom content of 10 to 30 atomic %. A photoreceptor characterized by: 2. Hydrogen atom content of the charge transport layer is 10 to 30 atoms
ic% (if it contains fluorine atoms, the fluorine atom content is 0.5 to 10 atomic%). 3. The hydrogen atom content of photoconductive jf1 is l +J-3Q
The photoreceptor according to claim 1 or 2, wherein the photoreceptor has a fluorine atom content of 0.5 to atomic% if it contains fluorine atoms. 4. Nitrogen atom content of the surface modified layer is 10 to 70 atoms
ic, and the hydrogen atom content is 10 to 30 atoms.
The photoreceptor according to any one of claims 1 to 3, wherein the photoreceptor has a fluorine atom content of 0.5 to 10 atomic percent (if it contains fluorine atoms, the fluorine atom content is 0.5 to 10 atomic percent). 5. The thickness of the surface modified layer is ioo X ~ 5000 K,
The photoreceptor according to any one of claims 1 to 4, wherein the photoconductive layer has a thickness of 2500 X to 5 μm, and the charge transport layer has a thickness of 10 μm to 30 μm. 6. The thickness of the surface modified layer is 400X to 2000X! It is. A photoreceptor according to claim 5. 7. A charge blocking layer made of amorphous hydrogenated and/or fluorinated silicon carbide is formed between the charge transport layer and the conductive substrate, and this charge blocking layer is made N-type by doping with a group VA element of the periodic table. The photoreceptor according to any one of claims 1 to 6, which is 8. The charge blocking layer has a flow rate ratio of phosphine and monosilane (PHs) / (SiH4)≦2000
The photoreceptor according to claim 7, which is formed by glue discharge decomposition under folding conditions. 9. The carbon atom content of the charge pushing eyebrows is lO~30
atomic%, and the hydrogen atom content is 10 to 30
The photoreceptor according to claim 7 or 8, which has a fluorine atom content of 0.5 to 10 atomic % if it contains fluorine atoms. 10- The photoreceptor according to any one of claims 7 to 9, wherein the charge punching layer has a thickness of 4001 to 1 μm.