JPS6148865A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To improve the electrostatic charge characteristic of an electrophotographic sensitive body having an amorphous photoconductive layer consisting essentially of silicon and/or germanium on a conductive substrate by providing an insulating amorphous silicon oxide (a-SiOx) layer between the substrate and the photoconductive layer. CONSTITUTION:The insulating amorphous silicon oxide (a-SiOx) layer is provided on the substrate, then the photoconductive layer contg. the amorphous silicon and or amorphous germanium is formed on said a-SiOx layer by glow discharge decomposition onto the substrate. The electrophotographic sensitive body obtd. in the above-mentioned manner has such characteristics as high electrostatic charging power (surface potential in the stage of corona charge), small dark attenuation, stabilized repetitive charge characteristics, the freedom of the exfoliation of the amorphous photoconductive layer from the substrate and the absence of the residual potential.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an electrophotographic photoreceptor.

(Conventional technology) Conventionally, the photoconductive layer of the photoconductive layer is ca's.

A product in which fine powder such as ZnO is dispersed and coated in an organic substance.

As-? Organic semiconductors such as amorphous se added with Te, polyvinylcarbazole, and trinitrofluorene have been used. However, OdS.

Resin dispersion materials such as ZnO have problems with moisture resistance.
7-v-lua 7s 8e has the problems of crystallization under high temperatures and the toxicity of the material itself to the human body, and organic medium conductive materials have problems with printing durability of 1c.

(Problems to be solved by the invention) Hydrogenated amorphous silicon (hereinafter referred to as RA-131: H
ra-Ge) and amorphous germanium hydride (hereinafter referred to as ra-Ge:HJ) are attracting attention. , a-8i:H as a photoreceptor.

a-G6;)l and mixtures thereof a-5iGay
: E is.

It has excellent light sensitivity and printing durability, and can control the spectral density.

It has the advantage of not having any toxicity problems.

A-81:H photoreceptors and the like have these advantages by 4A, but when used for electrostatic photography, there are problems in the characteristics of the band 11.

That is, for example, the specific resistance of a-8i:HII in the dark is /Qa -/ (712 Ω · , which is a small value compared to conventional photoreceptor materials.The ninth one is a-ai:
If the H film is simply deposited on a conductive substrate, the surface potential during corona charging will decrease even in the dark, and the repeated charging characteristics cannot be said to be good (for example, 1%). /G No. 33 Publication 1% Kaishoj / -
J, 2, see Geta Publication).

(Means for Solving the Problems) Therefore, the inventors of the present invention conducted thorough studies with the aim of improving these points and developing an electrophotographic photoreceptor with good charging voltage characteristics, and as a result, they arrived at the present invention. did.

In other words, the gist of the present invention is to provide an electrophotographic photoreceptor having an amorphous photoconductive layer mainly composed of silicon and/or germanium on a conductive substrate, in which an insulating amorphous silicon oxide layer is provided between the substrate and the photoconductive layer. (a-6iOme) An electrophotographic photosensitive member is provided with a jfA.

The present invention will be explained in detail below.

First, in the electrophotographic photoreceptor according to the present invention, the substrate is usually slower than metal.

For example, metals include aluminum and copper.

Examples include iron, nickel, tantalum, stainless steel, etc. (including those in which metals such as aluminum are added by vapor deposition on a support made of ceramics or organic materials), but silicon, germanium, ff- Those to which semiconductors such as FF group (Zn 8, etc.), III-V group (GaAs, etc.), and organic semiconductors are added may also be used.

Next, in the photoreceptor according to the present invention, an insulating amorphous silicon oxide (a-8107) layer is provided on the above substrate.

That is, “mH2n+t (n≧/) and/or B
It is formed by glow discharge using ia Ktn + * (X is a halogen atom) and an oxidizing gas, or by thermal decomposition. hm element as an oxidizing gas used in glow discharge
N2o, No, N02J 00100.10s
In addition, these oxidizing gases diluted with an inert gas such as td diluted gas or ~7 are used.Air is also used, but preferably oxygen gas diluted with a rare gas (usually 02
#degree0,0/~! Ovol, %) is used. The pressure inside the device during glow discharge is 1 usually 0.0 j ~ j
Selected from around Torr. In a-8iOx, X
is usually 0. /≦X≦ko, from the range of 3 S tJ,”;
The thickness of the h, a-Sio, layer is usually 0.02
~0. selected from the range of jμ.

A photoconductive layer containing amorphous silicon and (J/Jl;t) amorphous germanium is formed on the substrate using a glow discharge decomposition button. The pressure is /~!θμm, preferably 70-30μm.

In the case of this glow discharge decomposition, for example, in the case of a photoelectric layer made of amorphous silicon, 51nH2, +2.5inX2. n42 (X:/'
The SIH method is carried out using a gas containing (n≧7), etc., in a superatmospheric pressure atmosphere, using a DC bias method, a direct current bias method, or a radio frequency method. For this glow discharge, depending on the purpose, boron,
It is possible to dope the material with carbon dioxide, sulfur, oxygen, etc., at a constant value of about 0.0% to 0.0%.

As a carrier gas, use N2. He, 'Ar,
A commonly used gas such as N2 gas may be used.

Also, the substrate temperature is 2jθ~3! Selected from the range of θ°C.

When forming the above photoconductive layer, 5iIll) 1. .

+2 or 10% as the concentration of 51nx2n+2 gas
or more (volume ratio), ``cL pressure, 2 o ov ~ i K
V, Na density: 0.0/~2 mA/g
l, and the pressure (layer growth phase) is in the range of about θ,/~j Torr.

In the photoreceptor according to the present invention, the interface between the a'-8iOx layer and the amorphous photoconductive layer is preferably as follows.

Constructed to be discontinuous. This discontinuity is
It means to prevent oxygen from entering the photoconductive layer, &! In the photo, after forming the a-8iOx layer, the plasma was stopped and the source gas was exhausted.

Next, first-order amorphous light d! It can be constructed by adding raw material gas for forming an electric layer.

Specifically, the rate of change in the 0/S1 ratio in the film thickness direction.

The structure is such that at the interface between the a-810 layer and the photoconductive layer, the film thickness changes by an order of magnitude per .mu.m or more, preferably by 7 orders of magnitude per .mu.m.

Furthermore, the electrophotographic photoreceptor according to the present invention is a light guide i! A surface retaining layer of each glaze can be provided on the layer.

The electrophotographic photoreceptor that is heated as described above has a high charging ability (surface potential when the corona band is removed).

# Repetitive charging 4 with little decrease? I: The properties are stabilized, there is no peeling of the amorphous photoconductive layer from the substrate, and
(Example) The present invention will be described in more detail in Example 1 below.

In the examples, "φ" and "泵" for gas concentration are based on the capacity. , heated with an oil diffusion pump at a temperature of 300° C. for 3 a minute in a vacuum of p, j X / 0−′ Torr or less. ,1,1F
Return the air to the rotary pump and lower the substrate temperature to 3.20℃
Nishi Teshiran (SiB, )! 500M pressure 6.
Set to 6 Torr. A 600 Hz AC voltage (
Several hundred V) is applied to generate a glow discharge between the grounded electrode and the insulating a-,:5xox layer! minute+i:i
J was deposited (film thickness θ, /μm) (the X-ray microanalyzer (EPMA) analysis value of the O/Si atomic ratio X was about 2./μm).

Next, the reaction gas f 3iH4j o 500M, B,
H6/2(2(,270pIn) x, g So(:t
M (B211,7BLH, -4t09%), NHs
/”θ(/%) 48 C!OM (NHs
/S1H4=0,J%)-02/He (2
%) Cut to 0,6500M (o2/sia, = Q, θ da%)! ! li! A photoconductive layer having a film thickness of Z μm was formed by douglow discharge for 3 minutes at a pressure of /, / Torr and a substrate temperature of J′, 2 (7° C.).

The charging ability and dark decay rate of the obtained photoconductor were measured using a photoconductor evaluation machine (F, X'A) (corona voltage + KV
).

Fire intelligence 1 ability 30. j V/μm1 dark decay rate ≦, 7 chi/2.

Comparative Example 1 A photoreceptor was obtained by glow discharge in the same manner, except that no a-sIox layer was provided in M flj /.

i 71V power/76θV/μm, darkening rate 20.0%/
It was a carp.

Example λ A photoreceptor (thickness j, 9
μn1) was obtained.

Oa -5inxJ@N20/S iH, flow rate ratio! = Hiro 1 Eli hair = 3 SCO
M pressure θ, 9 j 'I'Orr substrate temperature 32! ℃ Glow discharge decomposition (AO!00Hz) 9 minutes film thickness 0.
Ko! μm 0a-8i: HM SiH, 20SC0M B2H6/1(, (/2jppm) 7 SOCM (
B2H, /biH, = &1-91Xn) Pressure /
,,2 Torr Substrate temperature 323℃ Glow discharge time 100 minutes Corona voltage +4 KV, Light intensity! IFA repeated charging characteristics were measured using Lux, and the results are shown in Figure 8g1.

Note that the residual potential was 10 V or less, and no increase was observed even after repeated testing.

Comparative Example λ A photoconductive layer was formed by glow discharge under the following conditions without providing an a-Si corner layer to obtain a photoreceptor (thickness: 30/μfrL).

Reaction gas composition: Same as Example 2 Pressure 0.9 Torr Substrate temperature 3 pieces! °C Glow discharge time 600 minutes Corona voltage + jKV (use +r xv was adopted to match the initial charging voltage with that of the photoreceptor in the example), light intensity! The EPA repeatability was measured using Lux, and the results are shown in Figure 1.

[Brief explanation of drawings]

FIG. 1 shows the repeated charging characteristics of the photoreceptors obtained in Example 1 of the present invention and Comparative Example λ. The horizontal axis shows the number of repetitions, and the vertical axis shows the surface potential (v). ○: Example, ・: Comparative example
indicates the value for Akira 1 Figure repeating number

Claims (1)

[Claims] (1) In an electrophotographic photoreceptor having an amorphous photoconductive layer mainly composed of silicon and/or germanium on a conductive substrate, an insulating amorphous silicon oxide (a-SiO_x) layer is provided between the substrate and the photoconductive layer. An electrophotographic photoreceptor characterized by being provided with.