JPH0454944B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is directed to light (here, light in a broad sense, including ultraviolet rays, visible rays, infrared rays, X-rays, r-rays, etc.)
It relates to photoconductive members sensitive to electromagnetic waves such as. As a photoconductive material for forming a photoconductive layer in a solid-state imaging device, an electrophotographic image forming member in the image forming field, or a document reading device, it is highly sensitive,
Must have a high signal-to-noise ratio [photocurrent (Ip)/dark current (Id)], have absorption spectral characteristics that match the spectral characteristics of the irradiated electromagnetic waves, have fast photoresponsiveness, and have the desired dark resistance value. Fixed imaging devices are sometimes required to have characteristics such as being non-polluting to the human body and being able to easily process afterimages within a predetermined time. Particularly in the case of an electrophotographic image forming member incorporated into an electrophotographic apparatus used in an office as a business machine, the above-mentioned non-polluting property during use is an important point. Based on these points, amorphous silicon (hereinafter referred to as a-Si) is a photoconductive material that has recently attracted attention. As a photographic image forming member, application to a photoelectric conversion reader is described in DE 2933411. However, conventional photoconductive members having photoconductive layers composed of a-Si have poor electrical, optical, and photoconductive properties such as dark resistance, photosensitivity, and photoresponsiveness, as well as moisture resistance. The reality is that there are points that could be further improved in terms of usage environment characteristics and stability over time, which require a combined improvement in characteristics. For example, when applied to electrophotographic image forming members, when trying to achieve high photosensitivity and high dark resistance at the same time, in the past, it has often been observed that residual potential remains during use, and this type of photoconductive member When used repeatedly for a long period of time, fatigue accumulates due to repeated use, resulting in a so-called ghost phenomenon in which an afterimage occurs. For example, according to many experiments conducted by the present inventors, a-Si as a material constituting the photoconductive layer of an electrophotographic image forming member can be replaced with conventional inorganic photoconductive materials such as Se, CdS, ZnO, etc. Although it has many advantages compared to organic photoconductive materials such as PVCz and TNF,
Charging treatment for forming an electrostatic image on the photoconductive layer of an electrophotographic imaging member having a single-layer photoconductive layer made of a-Si that has been given properties for use as a conventional solar cell. However, the dark decay is extremely fast even when the electrophotographic method is applied, making it difficult to apply normal electrophotography, and in a humid atmosphere, the above tendency is remarkable, and in some cases, the electrostatic charges may be retained until the development time. It has been found that there are some points that can be resolved, such as cases in which it is almost impossible to hold. Furthermore, when the photoconductive layer is composed of a-Si material, hydrogen atoms, halogen atoms such as fluorine atoms, chlorine atoms, etc., and electrically conductive type Boron atoms, phosphorus atoms, etc. are included for control purposes, and other atoms are included as constituent atoms in the photoconductive layer for the purpose of improving other properties. In this case, problems may arise in the electrical or photoconductive properties of the formed layer. That is, for example, the lifetime of photocarriers generated by light irradiation in the formed photoconductive layer may not be sufficient, or the injection of charges from the support side may not be sufficiently prevented in dark areas. This occurs in many cases. Therefore, while efforts are being made to improve the properties of the a-Si material itself, it is also necessary to take measures to obtain the desired electrical, optical, and photoconductive properties as described above when designing photoconductive members. There is. The present invention has been made in view of the above points, and includes a
-As a result of intensive research and study on Si from the viewpoint of its applicability as a photoconductive member used in electrophotographic image forming members, fixed imaging devices, reading devices, etc., we found that silicon atoms an amorphous material (amorphous material) containing at least either a hydrogen atom (H) or a halogen atom (X), so-called hydrogenated amorphous silicon, halogenated amorphous silicon, or halogen-containing hydrogenated It is designed to specify the layer structure of a photoconductive member having a photoconductive layer composed of amorphous silicon (hereinafter referred to as "a-Si(H,X)"). The produced photoconductive member not only exhibits extremely excellent properties in practical use, but also surpasses conventional photoconductive members in all respects, especially as a photoconductive member for electrophotography. This is based on the discovery that it has certain properties. The present invention is an all-environment type in which the electrical, optical, and photoconductive properties are almost always stable without being controlled by the usage environment, and it is extremely resistant to light fatigue and does not cause deterioration even after repeated use. The main object of the present invention is to provide a photoconductive member which has excellent durability and has no or almost no residual potential observed. Another object of the present invention is that when applied as an electrophotographic image forming member, it has sufficient charge retention ability during charging processing for electrostatic image formation, and ordinary electrophotographic methods can be applied extremely effectively. An object of the present invention is to provide a photoconductive member having excellent electrophotographic properties. Still another object of the present invention is to provide a photoconductive member for electrophotography that can easily produce high-quality images with high density, clear halftones, and high resolution. Yet another object of the present invention is high photosensitivity,
It is also an object to provide a photoconductive member having high signal-to-noise ratio characteristics and good electrical contact with the support. The photoconductive member of the present invention includes a support for the photoconductive member, a first amorphous layer having photoconductivity made of an amorphous material having silicon atoms as a matrix, and silicon atoms and carbide atoms. and a second amorphous layer made of an amorphous material consisting of hydrogen atoms, wherein the first amorphous layer contains atoms as constituent atoms over its entire layer region. the oxygen atoms are continuous in the layer thickness direction, and are contained in a state where they are more distributed toward the support side, and The layer is characterized in that the atoms belonging to the group are contained uniformly and continuously in the layer thickness direction. The photoconductive member of the present invention designed to have the above-mentioned layer structure can solve all of the above-mentioned problems, and has extremely excellent electrical, optical, and photoconductive properties and a usage environment. Show characteristics. In particular, when applied as an image forming member for electrophotography, it has excellent charge retention ability during charging processing, has no influence of residual potential on image formation, has stable electrical properties, and has high sensitivity. It has a high signal-to-noise ratio and is excellent in light fatigue resistance, repeated use characteristics, especially in a humid atmosphere, and is of high quality with high density, clear halftones, and high resolution. A visible image can be obtained. Hereinafter, the photoconductive member of the present invention will be explained in detail with reference to the drawings. FIG. 1 is a schematic structural diagram schematically shown to explain the layer structure of the photoconductive member of the present invention. A photoconductive member 100 shown in FIG. 1 has a-Si (H,
a first amorphous layer with photoconductivity consisting of
102 and a second amorphous layer () 103,
The first amorphous layer ( ) 102 has constituent atoms that are continuous in the layer thickness direction and are
Contains oxygen atoms in a state where they are more distributed toward the 01 side, and also contains atoms belonging to Group Group of the Periodic Table (group atoms) uniformly and continuously in the layer thickness direction. In the present invention, the group atoms contained in the amorphous layer ( ) are used for a-Si (H, , a P-type impurity that provides P-type conductivity, such as B (boron), Al (aluminum), Ga
(gallium), In (indium), Tl (thallium), etc., and B and Ga are particularly preferably used. In the present invention, the content of group atoms contained in the amorphous layer ( ) as a substance that controls conduction characteristics is determined by the conduction characteristics required for the amorphous layer ( ) or the amorphous layer. It can be selected as appropriate based on the organic relationship, such as the characteristics of other layers provided in direct contact with the layer (2) and the relationship with the characteristics at the contact interface with the other layers. In the present invention, the content of the substance controlling conduction properties contained in the amorphous layer () is usually 0.01 to 5×10 4 atomic ppm, preferably 0.01 to 5×10 ⁴ atomic ppm.
0.5 to 1×10 ⁴ atomic ppm, optimally 1 to 5×10 ³
It is preferable to set it to atomic ppm. In order to structurally introduce group atoms as substances controlling conduction properties into the amorphous layer, a starting material for introducing group atoms is introduced in a gaseous state into a deposition chamber during layer formation. It may be introduced together with other starting materials for forming the first amorphous layer. As a starting material for such introduction of group atoms, it is desirable to employ a material that is gaseous at room temperature and pressure, or that can be easily gasified at least under layer-forming conditions. 2 to 10 show typical examples of the distribution state of oxygen atoms contained in the first amorphous layer of the photoconductive member of the present invention in the layer thickness direction. In FIGS. 2 to 10, the horizontal axis shows the distribution concentration C of oxygen atoms in the layer thickness direction, and the vertical axis shows the layer thickness of the first amorphous layer ( ) exhibiting photoconductivity. , t _B indicates the position of the interface on the support side, and t _T indicates the position of the interface on the opposite side to the support side. That is, the amorphous layer ( ) containing oxygen atoms is formed toward the t _T side rather than the t _B side. In the present invention, the amorphous layer () containing oxygen atoms is a-Si (H,
X) and exhibits photoconductivity. FIG. 2 shows a first typical example of the distribution state of oxygen atoms contained in the first amorphous layer ( ) in the layer thickness direction. In the example shown in FIG. 2, the surface on which the amorphous layer ( ) containing oxygen atoms is formed (the surface of the support 101 in FIG. 1) is in contact with the surface of the amorphous layer ( ). From the boundary surface position t _B to the position t ₁ , the distribution concentration C of oxygen atoms takes a constant value C ₁ and is contained in the amorphous layer ( ) where oxygen atoms are formed, and from the position t ₁ The distribution concentration C ₂ is gradually and continuously reduced up to the boundary surface position t _T . At the boundary surface position _tT , the distribution concentration C of oxygen atoms is _C3 . In the example shown in FIG. 3, the distribution concentration C of the contained oxygen atoms gradually and continuously decreases from the distribution concentration _C4 from position _tB to position _{tT .}
A distribution state is formed such that the distribution concentration is C ₅ at . In the case of Fig. 4, from position t _B to position t ₂ , the distribution concentration C of oxygen atoms is a constant value of concentration C ₆ ,
Between the position t ₂ and the position t _T , the distribution concentration C is gradually and continuously decreased, and at the position t _T , the distribution concentration C is substantially zero. In the case of Figure 5, the oxygen atom is located at a position lower than position t _B.
The distribution concentration C ₈ is gradually decreased continuously until reaching t _T , and becomes substantially zero at the position t _T. In the example shown in FIG. 6, the distribution concentration C of oxygen atoms is the distribution concentration C ₉ between the position t _B and the position t ₃ .
is a constant value, and at position t _T the distribution concentration C ₁₀
It is said that Between the position t ₃ and the position t _T , the distribution concentration C is linearly decreased from the position t ₃ to the position t _T . In the example shown in FIG. 7, from position t _B to position t ₄ , the distribution concentration C ₁₁ is a constant value, and from position t ₄ to position t _T , the distribution concentration C ₁₂ to distribution concentration C ₁₃ is a linear value. It is assumed that the distribution state decreases functionally. In the example shown in FIG. 8, from position t _B to position t _T
Until , the distribution concentration C of oxygen atoms decreases linearly from the concentration C ₁₄ to zero. In FIG. 9, from position _tB to position _t5 , the distribution concentration C of oxygen atoms decreases linearly from distribution concentration _C15 to distribution concentration _C16 , and at position _t5
An example is shown in which the distribution concentration C ₁₆ is kept at a constant value between and the position t _T . In the example shown in FIG. 10, the distributed concentration C of oxygen atoms is the distributed concentration C ₁₇ at position t _B ;
Until reaching position t ₆ , this distribution concentration C ₁₇ initially decreases slowly, and near position t ₆ ,
It is rapidly decreased to a distribution concentration C ₁₈ at position t ₆ . Between position t ₆ and position t ₇ , the concentration is rapidly decreased for the first time, and then it is gradually decreased to become C ₁₉ at position t ₇ , and the distribution concentration between position t ₇ and position t ₈ is In between, it gradually decreases very slowly and reaches the distribution concentration C ₂₀ at position t ₈ . position t ₈ and position
During the period _tT , the distribution concentration _C20 is reduced to substantially zero according to a curve shaped as shown in the figure. As described above with reference to FIGS. 2 to 10, some curved examples of the distribution state of oxygen atoms contained in the amorphous layer ( ) in the layer thickness direction, in the present invention, the support side In this case, there is a part where the distribution concentration C of oxygen atoms is high, and on the interface _tT side, the distribution state C has a part where the distribution concentration C is lower than that on the support side. An amorphous layer () is provided on the support. In the present invention, the first amorphous layer ( ) preferably has localized regions A containing oxygen atoms at a high concentration toward the support side, as described above. The localized region A is provided within 5μ from the interface position _tB , if explained using the symbols shown in FIGS. 2 to 10. In the present invention, the localized region A may be the entire layer region L _T up to 5 μm thick from the interface position t _B , or may be a part of the layer region L _T. Whether the localized region A is a part or all of the layer region L _T depends on the first amorphous layer () to be formed.
It is determined as appropriate according to the characteristics required. The localized region A is preferably such that the maximum Cmax of the content distribution value (distribution concentration value) of oxygen atoms is usually 1 atomic% or more with respect to silicon atoms, as the distribution state of oxygen atoms contained therein in the layer thickness direction. is 3atomic
It is desirable that the layer be formed in such a manner that a distribution state of at least 5 atomic % can be obtained. That is, in the present invention, the amorphous layer containing oxygen atoms has a layer thickness of 5 μm from the support side.
The maximum value of the distribution concentration within (layer region 5 μ thick from t _B )
It is formed so that Cmax exists. As described above, by providing the localized region A containing a high concentration of oxygen atoms on the side of the support in the amorphous layer (), the support and the first amorphous layer ( ) can be more effectively promoted. In the photoconductive member of the present invention, the layer thickness of the first amorphous layer ( ) is set such that the first amorphous layer ( ) having desired characteristics is formed on the support. It is determined according to the purpose when designing the layer, and it is usually 1 to 100μ, preferably 1 to 80μ, and most preferably 2 to 50μ. In the present invention, specific examples of the halogen atom (X) contained in the first amorphous layer (X) as necessary include fluorine, chlorine, bromine, and iodine, particularly fluorine. , chlorine can be mentioned as suitable. In the present invention, a discharge phenomenon such as a glow discharge method, a sputtering method, or an ion plating method is used to form the first amorphous layer ( ) composed of a-Si(H,X). It is made by vacuum deposition method. For example, to form the first amorphous layer ( ) composed of a-Si (H, Together with the supply source gas, a source gas for introducing hydrogen atoms (H) and/or for introducing halogen atoms (X) is introduced into a deposition chamber whose interior can be reduced in pressure to generate a glow discharge within the deposition chamber. A layer made of a-Si (H, In addition, when forming by sputtering, hydrogen atoms (H ) or/and a gas for introducing halogen atoms (X) may be introduced into the deposition chamber for sputtering. As the raw material gas for supplying Si used in the present invention, silicon hydride (silanes) in a gaseous state or that can be gasified such as SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ , Si ₄ H ₁₀ is effective. Among them, Si ₂ H ₄ and SiH ₆ are particularly preferred in terms of ease of layer creation work and good Si supply efficiency. Many halogen compounds are effective as the raw material gas for introducing halogen atoms used in the present invention, such as halogen gas, halides, interhalogen compounds, halogen-substituted silane derivatives, etc. Preferred examples include halogen compounds that can be gasified. Further, a silicon compound containing a halogen atom, which is in a gaseous state or can be gasified and whose constituent elements are a silicon atom and a halogen atom, can also be mentioned as an effective compound in the present invention. Specifically, halogen compounds that can be suitably used in the present invention include fluorine, chlorine, bromine,
Iodine halogen gas, BrF, ClF, ClF ₃ ,
Examples include interhalogen compounds such as BrF ₅ , BrF ₃ , IF ₃ , IF ₇ , ICl, and IBr. Preferred examples of silicon compounds containing halogen atoms, so-called silane derivatives substituted with halogen atoms, include silicon halides such as SiF ₄ , Si ₂ F ₆ , SiCl ₄ , and SiBr ₄ . I can do it. When forming the characteristic photoconductive member of the present invention by a glow discharge method using such a silicon compound containing a halogen atom, silicon hydride gas is used as a raw material gas capable of supplying Si. Even if you don't,
A first amorphous layer () made of a-Si:X can be formed on a predetermined support. When manufacturing the first amorphous layer ( ) containing halogen atoms according to the glow discharge method, basically silicon halide gas, which is a raw material gas for supplying Si, and Ar, H ₂ , He, etc. gases, etc. are introduced into the deposition chamber for forming the first amorphous layer () at a predetermined mixing ratio and gas flow rate, and a glow discharge is generated to form a plasma atmosphere of these gases. The first amorphous layer () on a given support by
However, in order to introduce hydrogen atoms, a predetermined amount of a silicon compound gas containing hydrogen atoms may be mixed with these gases to form a layer. Moreover, each gas may be used not only as a single species but also as a mixture of multiple species at a predetermined mixing ratio. To form the first amorphous layer () made of a-Si(H, Then, this is sputtered in a predetermined gas plasma atmosphere, and in the case of ion plating method, polycrystalline silicon or single crystal silicon is housed in a deposition boat as an evaporation source, and this silicon evaporation source is used by resistance heating method or This can be done by heating and evaporating the flying evaporates using an electron beam method (EB method) or the like and passing them through a predetermined gas plasma atmosphere. At this time, in order to introduce halogen atoms into the layer formed by either the sputtering method or the ion blating method, a gas of the above-mentioned halogen compound or a silicon compound containing the above-mentioned halogen atoms is introduced into the deposition chamber. It is sufficient to introduce the gas to form a plasma atmosphere of the gas. In addition, when introducing hydrogen atoms, a raw material gas for introducing hydrogen atoms, such as H ₂ or the above-mentioned silane gases, is introduced into a deposition chamber for sputtering to form a plasma atmosphere of the gas. Just do it. In the present invention, the above-mentioned halogen compounds or halogen-containing silicon compounds are effectively used as raw material gases for introducing halogen atoms, but in addition, HF, HCl,
Hydrogen halides such as HBr, HI, SiH ₂ F ₂ , SiH ₂
Halogen-substituted silicon hydrides such as I ₂ , SiH ₂ Cl ₂ , SiHCl ₃ , SiH ₂ Br ₂ , SiHBr ₃ and other gaseous or gasifiable halides containing hydrogen atoms as one of their constituents are also effective. It can be mentioned as a starting material for forming the first amorphous layer. These halides containing hydrogen atoms introduce hydrogen atoms, which are extremely effective in controlling electrical or photoelectric properties, at the same time as halogen atoms are introduced into the layer during the formation of the first amorphous layer. Therefore, in the present invention, it is used as a suitable raw material for introducing halogen. In order to structurally introduce hydrogen atoms into the first amorphous layer (), in addition to the above, H ₂ , SiH ₄ , Si ₂
This can also be done by causing a discharge by causing a silicon hydride gas such as H ₆ , Si ₃ H ₈ , Si ₄ H ₁₀ , etc. to coexist with a silicon compound for supplying Si in the deposition chamber. For example, in the case of the reactive sputtering method, Si
Using a target, a gas for introducing halogen atoms and H ₂ gas, including inert gases such as He and Ar as necessary, are introduced into the deposition chamber to form a plasma atmosphere, and the Si target is sputtered. As a result, a first amorphous layer () made of a-Si(H,X) is formed on the substrate. Furthermore, a gas such as B ₂ H ₆ can also be introduced for doping with impurities. In the present invention, the first photoconductive member to be formed
Hydrogen atoms (H) contained in the amorphous layer () of
The amount of , the amount of halogen atoms (X), or the sum of the amounts of hydrogen atoms and halogen atoms is usually 1 to
It is desirable that the content be 40 atomic %, preferably 5 to 30 atomic %. In order to control the amount of hydrogen atoms (H) and/or halogen atoms (X) contained in the first amorphous layer (), for example, the support temperature or/and the amount of hydrogen atoms (H) or halogen atoms The amount of the starting material used to contain the atoms (X) introduced into the deposition system, the discharge force, etc. may be controlled. In the present invention, the diluting gas used when forming the first amorphous layer () by a glow discharge method or a sputtering method may be a so-called rare gas, e.g.
Preferred examples include He, Ne, Ar, and the like. In the present invention, to introduce oxygen atoms and periodic table group atoms into the first amorphous layer (),
When forming a layer by a glow discharge method, a reactive sputtering method, etc., a starting material for introducing group group atoms, a starting material for introducing oxygen atoms, or a starting material for forming an amorphous layer () containing both starting materials. This can be achieved by controlling the amount and containing it in the layer to be formed. When using the glow discharge method to form the first amorphous layer () into which oxygen atoms are introduced, the starting materials for forming the amorphous layer () described above may be selected as desired. A starting material for introducing oxygen atoms is added to the mixture. As such a starting material for introducing oxygen atoms, most of the gaseous substances containing at least oxygen atoms or gasified substances that can be gasified can be used. For example, a raw material gas containing silicon atoms (Si), a raw material gas containing oxygen atoms (O), and hydrogen atoms (H) or halogen atoms (X) as necessary. A raw material gas is used by mixing it at a desired mixing ratio, or a raw material gas whose constituent atoms are silicon atoms (Si) and a raw material gas whose constituent atoms are oxygen atoms (O) and hydrogen atoms (H) are used. , also in a desired mixing ratio, or a raw material gas containing silicon atoms (Si) and three atoms of silicon atoms (Si), oxygen atoms (O), and hydrogen atoms (H). It can be used in combination with a raw material gas having two constituent atoms. Alternatively, a raw material gas containing silicon atoms (Si) and hydrogen atoms (H) as constituent atoms may be mixed with a raw material gas containing oxygen atoms (O) as constituent atoms. Specifically, for example, oxygen (O ₂ ), ozone (O ₃ ),
- Nitrogen oxide (NO), nitrogen dioxide (NO ₂ ), nitrogen monooxide (N ₂ O), nitrogen sesquioxide (N ₂ O ₃ ), nitrogen tetraoxide (N ₂ O ₄ ), nitrogen pentoxide (N ₂ O ₅ ), nitrogen trioxide (NO ₃ ), silicon atoms (Si), oxygen atoms (O), and hydrogen atoms (H) as constituent atoms, such as disiloxane, H ₃ SiOSiH ₃ , trisiloxane H ₃ SiOSiH ₂ Examples include lower siloxanes such as OSiH ₃ . To form the first amorphous layer () containing oxygen atoms by the sputtering method, a single crystal or polycrystalline Si wafer or a SiO ₂ wafer,
Alternatively, the sputtering may be carried out by targeting a wafer containing a mixture of Si and SiO ₂ and sputtering them in various gas atmospheres. For example, if a Si wafer is used as a target, oxygen atoms and optionally hydrogen atoms or/
The raw material gas for introducing halogen atoms is diluted with a diluent gas as necessary and introduced into a deposition chamber for sputtering, and a gas plasma of these gases is formed to sputter the Si wafer. All you have to do is ring it. Alternatively, Si and SiO ₂ may be used as separate targets or by using a single mixed target of Si and SiO ₂ in an atmosphere of diluent gas as a sputtering gas or at least This is accomplished by sputtering in a gas atmosphere containing hydrogen atoms (H) and/or halogen atoms (X) as constituent atoms. As the raw material gas for introducing oxygen atoms, the raw material gas for introducing oxygen atoms among the raw material gases shown in the glow discharge example described above can be used as an effective gas also in the case of sputtering. First amorphous layer with introduced group atoms ()
To form the aforementioned first amorphous layer ()
In the formation of the first amorphous layer (), together with the raw material gas for forming the amorphous layer () described above, a gaseous or gasifiable starting material for introducing group atoms is in a gaseous state. It is sufficient if it is introduced into a vacuum deposition chamber for the formation of . The content of Group Atoms introduced into the amorphous layer (2) can be determined by controlling the gas flow rate, gas flow rate ratio, discharge power, etc. of the starting material for Group Atom introduction introduced into the deposition chamber. Therefore, it can be controlled arbitrarily. The starting materials for introducing group atoms that are effectively used in the present invention are B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H ₉ , B ₅ H ₁₁ , _{B6H10 ,}
Boron hydride such as B ₆ H ₁₂ , B ₆ H ₁₄ , BF ₃ , BCl ₃ ,
Examples include boron halides such as BBr ₃ . Other examples include AlCl ₃ , GaCl ₃ , Ga(CH ₃ ) ₃ , InCl ₃ and TlCl ₃ . In the present invention, in the first amorphous layer (),
Glow discharge is used to change the distribution concentration of oxygen atoms contained in the layer () in the layer thickness direction to form an amorphous layer () having a desired distribution state (depth profile) in the layer thickness direction. In this case, this can be achieved by appropriately changing the flow rate of the gas containing oxygen atoms whose distribution concentration is to be changed as desired. For example, the opening of a predetermined needle valve provided in the middle of the gas flow path system may be gradually changed by any commonly used method such as manually or by using an externally driven motor. At this time,
The rate of change in the flow rate does not need to be linear; for example, a microcomputer or the like can be used to control the flow rate according to a pre-designed rate-of-change curve to obtain a desired content rate curve. When the first amorphous layer () is formed by a sputtering method, by controlling the distribution concentration of oxygen atoms contained in the first amorphous layer () in the layer thickness direction. In order to form a desired distribution state (depth profile) of oxygen atoms in the layer thickness direction, first, as in the case of the glow discharge method, a gas of a substance for introducing oxygen atoms is used, and the gas is deposited. This is accomplished by appropriately changing the flow rate of the gas introduced into the chamber as desired. Second, sputtering targets such as Si and SiO ₂
If a mixed target is used, this can be done by changing the mixing ratio of Si and SiO ₂ in advance in the direction of the layer thickness of the target. In the photoconductive member 100 shown in FIG.
It is provided in order to achieve the objectives of the present invention mainly in terms of moisture resistance, continuous repeated use characteristics, pressure resistance, use environment characteristics, and durability. Further, in the present invention, the first amorphous layer ()
Since each of the amorphous materials forming the and the second amorphous layer () has a common constituent element of silicon atoms, chemical stability can be sufficiently ensured at the laminated interface. has been done. The second amorphous layer () is an amorphous material [a-
(Si _x C _1-x )yH _1-y , where 0<x<, y<1]. The second amorphous layer ( ) composed of a-(Si _x C _1-x )yH _1-y can be formed by glow discharge method, sputtering method, ion implantation method, or ion plating method. , electron beam method, etc. These manufacturing methods are selected and adopted as appropriate depending on factors such as manufacturing conditions, amount of equipment capital investment, manufacturing scale, and desired characteristics of the photoconductive member to be manufactured. It is relatively easy to control the manufacturing conditions for manufacturing a photoconductive member having silicon atoms, and it is easy to introduce carbon atoms and hydrogen atoms together with silicon atoms into the second amorphous layer (2). Due to their advantages, the glow discharge method or the sputtering method is preferably employed. Furthermore, in the present invention, the second amorphous layer () may be formed by using a glow discharge method and a sputtering method in the same apparatus system. To form the second amorphous layer ( ) by the glow discharge method, the raw material gas for forming a-(Si _x C _1-x )yH _1-y is mixed with a diluting gas as needed. The mixture is mixed at a fixed mixing ratio and introduced into a deposition chamber for vacuum deposition in which a support is installed, and the introduced gas is turned into gas plasma by generating a glow discharge to form a gas that has already been formed on the support. The first amorphous layer ()
It is sufficient to deposit a-(Si _x C _1-x )yH _1-y thereon. In the present invention, the raw material gas for forming a-(Si _x C _1-x )yH _1-y is at least one of silicon atoms (Si), carbon atoms (C), and hydrogen atoms (H). Most of the gaseous substances having constituent atoms or the gasified substances that can be gasified can be used. When using a raw material gas containing Si as one of Si, C, and H, for example, a raw material gas containing Si as a constituent atom, a raw material gas containing C as a constituent atom, and a raw material gas containing H as a constituent atom. Alternatively, a raw material gas containing Si and a raw material gas containing C and H may be mixed at a desired mixing ratio. or with a raw material gas containing Si as a constituent atom,
It can be used in combination with a raw material gas whose constituent atoms are Si, C, and H. Alternatively, a raw material gas containing Si and H as constituent atoms may be mixed with a raw material gas containing C as constituent atoms. In the present invention, Si and H are effectively used as raw material gases for forming the second amorphous layer ().
SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ , Si ₄ whose constituent atoms are
Silicon hydride gas such as silanes such as H ₁₀ , whose constituent atoms are C and H, for example, carbon number 1
-4 saturated hydrocarbons, ethylene hydrocarbons having 2 to 4 carbon atoms, acetylenic hydrocarbons having 2 to 3 carbon atoms, and the like. Specifically, saturated hydrocarbons include methane (CH ₄ ), ethane (C ₂ H ₆ ), propane (CH ₈ ), n
-butane (n- _C4H10 ) _, pentane ( _C5H12 ), ethylene ( _C2H4 ) as _an ethylene _hydrocarbon
Propylene (C ₃ H ₆ ), 1-butene (C ₄ H ₈ ), 2-butene (C ₄ H ₈ ), isobutylene (C ₄ H ₈ ), pentene (C ₅ H ₁₀ ), and acetylenic hydrocarbons. ,
Acetylene (C ₂ H ₂ ), Methylacetylene (C ₃
H ₄ ), butyne (C ₄ H ₆ ), and the like. Examples of the source gas containing Si, C, and H as constituent atoms include alkyl silicides such as Si(CH ₃ ) ₄ and Si(C ₂ H ₅ ) ₄ . In addition to these raw material gases, H
Of course, H ₂ is also effectively used as the raw material gas for introduction. To form the second amorphous layer () by the sputtering method, target a single-crystal or polycrystalline Si wafer, a C wafer, or a wafer containing a mixture of Si and C; These may be performed by sputtering in various gas atmospheres. For example, if a Si wafer is used as a target, the raw material gas for introducing C and H is diluted with diluting gas as necessary, and introduced into a deposition chamber for sputtering to create a gas plasma of these gases. , and then sputtering the Si wafer. Alternatively, sputtering can be carried out in a gas atmosphere containing at least hydrogen atoms by using separate targets for Si and C or by using a single target in which Si and C are mixed. It is accomplished by doing so. As the raw material gas for introducing C or H, the raw material gas shown in the glow discharge example described above can be used as an effective gas also in the case of sputtering. In the present invention, so-called rare gases such as He, Ne, Ar, etc. can be used as the diluting gas when forming the second amorphous layer () by the glow discharge method or the sputtering method. It can be mentioned as a suitable one. The second amorphous layer ( ) in the present invention is carefully formed so as to provide the desired properties. In other words, substances whose constituent atoms are Si, C, and H can have structural forms ranging from crystalline to amorphous, depending on the conditions of their creation, and electrical properties ranging from conductive to semiconductive to immovable. and properties between photoconductive and non-photoconductive properties.
Accordingly, in the present invention, the preparation conditions are selected as desired so that a-(Si _x C _1-x )yH _1-y having desired characteristics depending on the purpose is formed. is carried out strictly. For example, in order to provide the second amorphous layer () with the main purpose of improving pressure resistance, a-(Si _x C _1-x )
yH _1-y is produced as an amorphous material with pronounced electrically insulating behavior under the conditions of use. In addition, if a second amorphous layer () is provided for the main purpose of improving the characteristics of continuous repeated use and the characteristics of the usage environment, the above-mentioned degree of electrical insulation will be relaxed to some extent, and it will be more effective against the irradiated light. As an amorphous material with a certain degree of sensitivity, a-(Si _x C _1-x )
yH _1-y is created. a-(Si _x C _1-x ) on the surface of the first amorphous layer ()
When forming the second amorphous layer ( ) consisting of yH _1-y , the temperature of the support during layer formation is an important factor that influences the structure and properties of the formed layer. In this case, a-(Si _x
It is desirable that the temperature of the support during layer formation be strictly controlled so that C _1-x )yH _1-y can be formed as desired. In order to effectively achieve the purpose of the present invention, the temperature of the support body when forming the second amorphous layer () may be determined as appropriate in accordance with the method of forming the second amorphous layer (). An optimal range is selected to perform the formation of the second amorphous layer (), typically at 50°C.
It is desirable that the temperature is between 100°C and 250°C, preferably between 100°C and 250°C. For the formation of the second amorphous layer (), glow discharge is used because delicate control of the composition ratio of atoms constituting the layer and control of the layer thickness are relatively easy compared to other methods. However, when forming the second amorphous layer () using these layer forming methods, the temperature during layer formation as well as the support temperature described above must be adjusted. Discharge power and gas pressure are one of the important factors that influence the characteristics of a-(Si _x C _1-x )yH _1-y that is created. The discharge power conditions for effectively producing a-(Si _x C _1-x )yH _1-y with good productivity, which has the characteristics to achieve the purpose of the present invention, are usually 10
~300W, preferably 20~200W. It is desirable that the gas pressure in the deposition chamber is usually about 0.01 to 1 Torr, preferably about 0.1 to 0.5 Torr. In the present invention, the preferable numerical ranges of the support temperature and discharge power for creating the second amorphous layer ( ) include the values in the above-mentioned ranges,
These layer creation factors are not determined independently and separately, but rather the desired properties a-(Si _x
It is desirable that the optimum value of each layer formation factor be determined based on the mutual organic relationship so that the second amorphous layer ( ) consisting of C _1-x )yH _1-y is formed. In the present invention, the amount of carbon atoms and hydrogen atoms contained in the second amorphous layer (2) is determined as desired to achieve the object of the present invention, as well as the production conditions of the second amorphous layer (2). The second amorphous layer () that provides the properties of
is an important factor in the formation of The amount of carbon atoms contained in the second amorphous layer ( ) in the present invention is usually 1×10 ^-3 to 90 atomic%
and preferably 1 to 90 atomic%, optimally
It is desirable that the content be 10 to 80 atomic%. The content of hydrogen atoms is usually 1 to 1.
It is desirable that the hydrogen atom content be 40 atomic%, preferably 2 to 35 atomic%, and optimally 5 to 30 atomic%.In practice, photoconductive members produced when the hydrogen atom content is in these ranges are It is considered to be excellent and can be fully applied. That is, if expressed as a-(Si _x C _1-x )yH _1-y above, x is usually 0.1 to 0.99999, preferably 0.1 to 0.99,
Optimally, it is 0.15 to 0.9, and y is usually 0.6 to 0.99, preferably 0.65 to 0.98, most preferably 0.7 to 0.95. The numerical range of the layer thickness of the second amorphous layer ( ) in the present invention is one of the important factors for effectively achieving the object of the present invention. The numerical range of the layer thickness of the second amorphous layer ( ) in the present invention is appropriately determined according to the desired purpose so as to effectively achieve the purpose of the present invention. In addition, the layer thickness of the second amorphous layer () is determined by the amount of carbon atoms and hydrogen atoms contained in the layer (),
The relationship with the layer thickness of the first amorphous layer () also needs to be appropriately determined as desired based on the organic relationship depending on the characteristics required for each layer region. There is. In addition, it is desirable to take into consideration economic efficiency, which takes into account productivity and mass production. The thickness of the second amorphous layer ( ) in the present invention is usually preferably 0.003 to 30 μm, preferably 0.004 to 20 μm, and most preferably 0.005 to 10 μm. The support used in the present invention may be electrically conductive or electrically insulating. Examples of the conductive support include NiCr, stainless steel, Al,
Examples include metals such as Cr, Mo, Au, Nb, Ta, V, Ti, Pt, and Pd, and alloys thereof. As the electrically insulating support, films or sheets of synthetic resins such as polyester, polyethylene, polycarbonate, cellulose, acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, glass, ceramic, paper, etc. are usually used. Ru. Preferably, at least the surface of these electrically insulating supports is conductively treated, and another layer is preferably provided on the conductively treated surface side. For example, if it is glass, NiCr,
Al, Cr, Mo, Au, Ir, Nb, Ta, V, Ti, Pt,
Conductivity can be imparted by providing a thin film made of Pd, In ₂ O ₃ , SnO 2 _, ITO (In ₂ O ₃ +SnO ₂ ), etc., or if it is a synthetic resin film such as polyester film, NiCr, Al ,Ag,Pb,Zn,Ni,
A thin film of metal such as Au, Cr, Mo, Ir, Nb, Ta, V, Ti, Pt, etc. is provided on the surface by vacuum evaporation, electron beam evaporation, sputtering, etc., or the surface is laminated with the above metal. , imparts conductivity to its surface. The shape of the support body is cylindrical,
The photoconductive member 100 shown in FIG. 1 may be used as an image forming member for electrophotography, for example, if the photoconductive member 100 of FIG. 1 is used as an electrophotographic image forming member. In the case of copying, it is desirable to have an endless belt shape or a cylindrical shape. The thickness of the support is determined appropriately so that a desired photoconductive member is formed, but if flexibility is required as a photoconductive member, the support can sufficiently function as a support. It is made as thin as possible within this range. However, in such cases, the thickness is usually 10μ or more in view of manufacturing and handling of the support, mechanical strength, etc. Next, an outline of an example of the method for manufacturing a photoconductive member of the present invention will be explained. FIG. 11 shows an example of a photoconductive member manufacturing apparatus. Gas cylinders 1102, 1103, and 1104 in the figure are sealed with raw material gases for forming the respective layers of the present invention. As an example, 1102 is SiH ₄ gas (purity
99.999%, hereinafter abbreviated as SiH ₄ /He. ) cylinder, 11
03 is B ₂ H ₆ gas diluted with He (purity 99.999
%, hereinafter abbreviated as B ₂ H ₆ /He. ) cylinder, 1104
is NO gas (99.99% purity) cylinder, 1105 is
_SiF4 gas diluted with He (purity 99.999% or less)
Abbreviated as SiF ₄ /He. ) cylinder, 1106 is a C ₂ H ₄ gas (99.99% purity) cylinder. In order to flow these gases into the reaction chamber 1101, valves 112 of gas cylinders 1102 to 1106 are used.
2 to 1126, confirm that the leak valves 1135 are closed, and also check that the inflow valves 1112 to 1126 are closed.
1116, check that the outflow valves 1117 to 1121 and the auxiliary valve 1132 are open, and first open the main valve 1134 to drain the reaction chamber 110.
1. Evacuate the inside of the gas pipe. Next, the vacuum gauge 1136
When the reading reaches approximately 5×10 ⁻⁶ torr, the auxiliary valve 1132 and the outflow valves 1117 to 1121 are closed. To give an example of forming the first amorphous layer () on the base 1137, the gas cylinder 1102
SiH ₄ /He gas, B ₂ H ₆ from cylinder 1103
Open valves 1122 to 1124 to supply NO gas from He gas and gas cylinder 1104, and outlet pressure gauge 1
The pressures of 127 to 1129 are adjusted to 1 Kg/cm ² , and the inflow valves 1112 to 1114 are gradually opened to flow into the mass flow controllers 1107 to 1109. Subsequently, the outflow valves 1117-111
9. Gradually open the auxiliary valve 1132 to allow each gas to flow into the reaction chamber 1101. At this time
The outflow valves 1117 to 1119 are adjusted so that the ratio of the SiH ₄ /He gas flow rate, NO gas flow rate, and B ₂ H ₆ /He gas flow rate becomes the desired value, and the pressure inside the reaction chamber is adjusted to the desired value. Adjust the opening of the main valve 1134 while checking the reading on the vacuum gauge 1136. Then, the temperature of the base 1137 becomes higher than that of the heating heater 1.
After confirming that the temperature is set in the range of 50 to 400°C by 138, the power supply 1140 is set to the desired power to generate a glow discharge in the reaction chamber 1101, and at the same time the rate of change is set in advance. The distribution concentration of oxygen atoms contained in the formed layer is controlled by operating the valve 1119 to gradually change the flow rate of NO gas according to the curve manually or by using an externally driven motor. As described above, the first amorphous layer () containing oxygen atoms and boron atoms is formed on the base 1137.
form. When containing halogen atoms in the first amorphous layer (2), the above gas may contain, for example, SiF ₄ /He.
is further added and sent into the reaction chamber 1101. Depending on the selection of gas species during the formation of the amorphous layer,
The layer formation speed can be further increased. for example
If layer formation is performed using Si ₂ H ₆ gas instead of SiH ₄ gas, the productivity can be increased several times or more. To form a second amorphous layer () on the first amorphous layer () created as described above,
For example, each of SiH ₄ gas and C ₂ H ₄ gas is diluted with a diluent gas such as He as necessary by the same valve operation as in the formation of the first amorphous layer (). This is achieved by flowing into the reaction chamber 1101 at a desired flow rate ratio and generating glow discharge according to desired conditions. The amount of carbon atoms contained in the second amorphous layer ( ) can be determined by arbitrarily changing the flow rate ratio of SiH ₄ gas and C ₂ H ₄ gas introduced into the reaction chamber 1101 as desired. This allows for control as desired. Needless to say, all outflow valves for gases other than those required for forming each layer are closed, and
When forming each layer, the gas used to form the previous layer is released into the reaction chamber 1101 and through the outflow valves 1117 to 1.
121 to the inside of the reaction chamber 1101, the outflow valves 1117 to
1121, open the auxiliary valve 1132, and fully open the main valve 1134 to temporarily evacuate the system to a high vacuum, as necessary. Example 1 Using the manufacturing apparatus shown in FIG. 11, an image forming member having an oxygen concentration distribution as shown in FIG. 12 within the amorphous layer was manufactured under the conditions shown in Table 1. The image forming member thus obtained was placed in a charging, exposing and developing device, corona charging was performed at 5 kV for 0.2 seconds, and a light image was immediately irradiated. A tungsten lamp was used as the light source, and a light intensity of 1.0 lux·sec was irradiated using a transmission type test chart. Immediately thereafter, a good toner image was obtained on the surface of the member by cascading a charged developer (including toner and carrier) over the surface of the member. The toner image thus obtained was once cleaned with a rubber plate, and the above image forming and cleaning process was repeated again. No deterioration of the image was observed even after repeating more than 150,000 times.

[Table] Example 2 Completely the same method as Example 1 except that the flow rate ratio of B ₂ H ₆ and SiH ₄ in the amorphous layer () was changed to change the B concentration contained in the layer. An imaging member was prepared by. For each of the image forming member samples No. 21 to 26 thus obtained, the steps of image formation, development, and cleaning as described in Example 1 were repeated approximately 50,000 times, and then image evaluation was performed. I got similar results.

[Table] ◎ Excellent ○ Good example 3 The basic distribution type of oxygen in the amorphous layer ( ) is as shown in Figure 3, and by changing the flow rate of NO,
Except for changing the oxygen concentration at d=1μ in the figure,
An image forming member was produced by the same method as in Example 1. For each of the image forming members thus obtained, the steps of image formation, development, and cleaning as described in Example 1 were repeated about 50,000 times, and then image evaluation was performed, and the results shown in Table 3 were obtained. .

[Table] ◎ High sensitivity and good image quality ○ Good image quality △ Very high sensitivity example 4 When forming the amorphous layer (), SiH ₄ gas and C ₂
An electrophotographic image forming member was prepared in exactly the same manner as in Example 1, except that the content ratio of silicon atoms and carbon atoms in the amorphous layer was changed by changing the flow rate ratio of H ₄ gas. was formed. After repeating the steps up to transfer approximately 50,000 times using the method described in Example 1 for each of the electrophotographic image forming members thus obtained, image evaluation was performed.
The results shown in the table were obtained.

[Table] Example 5 Electrophotographic imaging members (Samples Nos. 51 to 54 ) was formed. The evaluation results for each are shown in the table below.

【table】

[Table] Example 6 An image forming member was prepared in the same manner as in Example 1, except that the conditions for forming the amorphous layer () were changed as shown in Table 6, and the same evaluation as in Example 1 was conducted. I went there and got good results.

【table】 [Brief explanation of the drawing]

FIG. 1 is a schematic layer structure diagram for explaining the layer structure of the photoconductive member of the present invention, and FIGS. 2 to 10 respectively show the distribution state of oxygen atoms contained in the amorphous layer. An explanatory diagram for explaining, FIG. 11 is a schematic explanatory diagram of the device used in the present invention, and FIG. 12 is a diagram showing the distribution state of oxygen atoms contained in the amorphous layer in the example. It is an explanatory diagram to explain. 100...Photoconductive member, 101...Support, 1
02...First amorphous layer (), 103...Second amorphous layer (), 104...Free surface.

Claims (1)

[Claims] 1. A support for a photoconductive member, a first amorphous layer having photoconductivity made of an amorphous material whose matrix is silicon atoms, and an amorphous layer made of silicon atoms, carbon atoms, and hydrogen atoms. a second amorphous layer made of a solid material, the first amorphous layer comprising:
The constituent atoms include oxygen atoms and atoms belonging to Group 3 of the periodic table over the entire layer region, and the oxygen atoms are continuous in the layer thickness direction and extend toward the support side. A photoconductive member characterized in that the atoms are contained in a large distribution state and the atoms belonging to the group of the periodic table are contained uniformly and continuously in the layer thickness direction.