JPH0220099B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to light (here, light in a broad sense, including ultraviolet rays, visible rays, infrared rays, X-rays, γ-rays, etc.)
The present invention relates to photoconductive members for electrophotography that are 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 spectrum characteristics that match the spectral characteristics of the irradiated electromagnetic waves, have fast photoresponsiveness, and have the desired dark resistance value. At times, solid-state imaging devices are 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, chemical, and photoconductive properties such as dark resistance, photosensitivity, and photoresponsiveness, as well as use environment characteristics. Although individual improvements have been made in terms of stability, stability over time, and durability, the reality is that there is still room for further improvement in terms of improving overall properties. It is. For example, when applied to electrophotographic image forming members, when trying to achieve high photosensitivity and high dark resistance at the same time, it has often been observed in the past that residual potential remains during use. 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. In addition, when the photoconductive layer is composed of a-Si material, in order to improve its electrical and photoconductive properties, hydrogen atoms, halogen atoms such as fluorine atoms and chlorine atoms, 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 some cases, problems may arise in the electrical or photoconductive properties or voltage resistance of the formed layer. That is, for example, the lifetime of the photocarrier generated in the formed photoconductive layer by light irradiation is not sufficient, or the injection of charge from the support side is not sufficiently prevented in the dark area. There were cases where this occurred. Therefore, while efforts are being made to improve the properties of the a-Si material itself, it is necessary to take measures to solve all of the above-mentioned problems when designing photoconductive members for electrophotography. 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 and applicability as a photoconductive member used in electrophotographic image forming members, we found that silicon atoms are used as a matrix, hydrogen atoms H or Amorphous material containing at least one of halogen atoms X, so-called hydrogenated amorphous silicon, halogenated amorphous silicon, or halogen-containing hydrogenated amorphous silicon Use “X)”]
A photoconductive member designed and produced in such a way that the layer structure of the photoconductive member having a photoconductive layer composed of the following is specified not only shows extremely excellent properties in practical use, but also This is based on the discovery that it is superior in all respects to conventional photoconductive members, and has particularly excellent properties as a photoconductive member for electrophotography. The electrical, optical, and photoconductive properties of the present invention are almost unaffected by the usage environment, are always stable, are extremely resistant to light fatigue, do not deteriorate even after repeated use, and are highly durable. The main object of the present invention is to provide a photoconductive member for electrophotography (hereinafter referred to as "photoconductive member") in which no or almost no potential is 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,
An object of the present invention is to provide a photoconductive member having high signal-to-noise ratio characteristics and high voltage resistance. The photoconductive member of the present invention comprises a support for a photoconductive member for electrophotography and an amorphous material having silicon atoms as a matrix, and has a photoconductive layer thickness of 1 to 1.
100μ first amorphous layer, silicon atoms and 1×
a second amorphous layer with a layer thickness of 0.003 to 30 μ made of an amorphous material consisting of 10 ^-3 to 90 atomic% carbon atoms, and the first amorphous layer has carbon atoms as constituent atoms. The first layer region containing 0.001 to 50 atomic% of oxygen atoms and in contact with the support and occupying a part of the first amorphous layer and the constituent atoms of 0.01 to 5×
a second layer region having a layer thickness of 50μ or less containing atoms belonging to Group 1 of the periodic table of 10 ⁴ atomic ppm;
A layer having a portion on the support where the distribution state of oxygen atoms is higher than 500 atomic ppm, and a portion where the distribution state of oxygen atoms is lower on the second amorphous layer side than on the support side. The distribution state is non-uniform and continuous in the thickness direction, and the layer thickness T _B of the second layer region is smaller than the layer thickness T B of the second layer _region and the layer thickness of the first amorphous layer. It is characterized in that the layer thickness T obtained by excluding the relationship T _B /T≦1. 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, photoconductive properties, and pressure resistance. and usage environment characteristics. In particular, when applied as an electrophotographic image forming member, there is no influence of residual potential on image formation, its electrical characteristics are stable, and it is highly sensitive and has high
It has a high signal-to-noise ratio, has excellent light fatigue resistance and repeated use characteristics, and can stably and repeatedly produce high-quality images with high density, clear halftones, and high resolution. 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. The 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 ( ) 106 made of an amorphous material containing silicon atoms and carbon atoms. The first amorphous ( ) 102 is continuous in the layer thickness direction and is distributed more toward the support 101 , and is a first layer region (O) 103 containing oxygen atoms as constituent atoms. and a second layer region ( ) 104 containing group atoms as constituent atoms.
It has a layered structure configured to have. 1st
In the example shown in the figure, the first layer region (O) 10
3 has a layer structure in which part of the second layer region (O) 104 is occupied, and the first layer region (O) 103 and the second layer region (O)
The layer region () 104 is the first amorphous layer () 1
02 is unevenly distributed on the support body 101 side. The upper layer region 105 of the first amorphous layer (O) 102 does not substantially contain oxygen atoms and group group atoms, and the oxygen atoms are present in the first layer region (O) 103. is contained in the second layer region () 104. Of course, the first layer region (O) 103 also contains group atoms. In the present invention, the layer structure as described above is adopted because the first layer region (O) 103 has high dark resistance due to the inclusion of oxygen atoms, and the support 101 and the first amorphous layer. A focus is placed on improving the adhesion between the layer 102 and the upper layer region 105, and high sensitivity is focused on the upper layer region 105 without containing oxygen atoms.
The oxygen atoms contained in the first layer region (O) 103 are distributed continuously and non-uniformly in the layer thickness direction, and are parallel to the interface between the support 101 and the first amorphous layer (O) 102. In the present invention, the first amorphous layer (O) 10 is contained in the first layer region (O) 103 in a substantially uniform distribution state within the plane.
Group atoms contained in the second layer region ( ) 104 that constitutes Group 2 and contains group atoms are as follows:
B (boron), Al (aluminum), Ga (gallium),
In (indium), Tl (thallium), etc. are used, and B and Ga are particularly preferably used. In the present invention, the second layer region ( ) 104
The group atoms contained therein are distributed substantially uniformly in the layer thickness direction and in a plane parallel to the surface of the support 101. First layer region (O) 103 and upper layer region 105
Since the layer thickness of the photoconductive member is one of the important factors for effectively achieving the object of the present invention, the design of the photoconductive member should be carefully selected so that the formed photoconductive member has sufficient desired characteristics. Sufficient care must be taken when doing so. In the present invention, the upper limit of the layer thickness T _B of the second layer region ( ) 104 is usually 50 μm.
The thickness is preferably 30μ or less, most preferably 10μ or less. The lower limit of the layer thickness T of the upper layer region 105 is usually 0.5μ or more, preferably 1μ or more, and optimally 3μ or more. The lower limit of the layer thickness T _B of the second layer region ( ) 104 and the upper limit of the layer thickness T of the upper layer region 105 are based on the characteristics required for both layer regions and the first amorphous layer ( ).
It is appropriately determined as desired when designing the layers of the photoconductive member based on the mutual organic relationship with the characteristics required for the entire layer 102. In the present invention, as the lower limit of the layer thickness T _B and the upper limit of the layer thickness T, appropriate values are usually selected for each so as to satisfy the relationship T _B /T≦1. be done. In selecting the numerical values of the layer thickness T _B and the layer thickness T, it is more preferable to select the layer thickness T B and the _layer thickness so that the relationship T _B /T≦0.9, optimally, T _B /T≦0.8 is satisfied. Preferably, a value for the thickness T is determined. In the photoconductive member of the present invention shown in FIG.
Second layer region containing group atoms ()
Although the first layer region (O) 103 is formed within 104, the first layer region (O) and the second layer region () can be the same layer region. Furthermore, a case where the second layer region (O) is formed within the first layer region (O) can also be mentioned as one of the preferred embodiments. The amount of oxygen atoms contained in the first layer region (O) is determined as desired depending on the properties required of the photoconductive member to be formed, but is usually 0.001 to 50 atomic%. , preferably 0.002~
It is desirable that it be 40 atomic%, optimally 0.003 to 30 atomic%. If the layer thickness of the first layer region (O) is sufficiently thick or the ratio of the first amorphous layer (O) to the total layer thickness exceeds two-fifths or more, the first layer region (O) The upper limit of the amount of oxygen atoms contained in (O) is usually 30 atomic% or less, preferably
It is desirable that it be 20 atomic % or less, optimally 10 atomic % or less. In the present invention, the thickness of the first amorphous layer ( ) is usually 1 to 100 μm, preferably 1 to 100 μm, from the viewpoint of obtaining desired electrophotographic properties and economical efficiency. It is desirable that the thickness be 80μ, optimally 2 to 50μ. 2 to 10 show the distribution in the layer thickness direction of oxygen atoms contained in the first layer region (O) constituting the first amorphous layer ( ) of the photoconductive member in the present invention. Typical examples of conditions are shown. In the examples shown in FIGS. 2 to 10, the layer region () containing group atoms may be the same layer region as the layer region (O) or include the layer region (O). , or a part of the layer region (O) may be shared, so in the following explanation, the layer region () containing group atoms will not be particularly explained. Don't mention it unless it's necessary. In FIGS. 2 to 10, the horizontal axis represents the distribution concentration C of oxygen atoms, and the vertical axis represents the layer region (O) constituting the amorphous layer exhibiting photoconductivity and containing oxygen atoms.
indicates the layer thickness T _B , where t _B is the position of the interface on the support side,
t _T indicates the position of the interface on the opposite side to the support side. That is, in the layer region (O) containing oxygen atoms, the layer is formed from the t _B side toward the t _T side. In the present invention, the layer region (O) containing oxygen atoms is a-Si (H,
X) and occupies a part of the first amorphous layer () exhibiting photoconductivity. In the present invention, the layer region (O) is the support 10 of the first amorphous layer ( ) as shown in the example of FIG.
a first amorphous layer ( ) 102 including the surface of one side;
It is preferable that it be provided in the lower layer region of. FIG. 2 shows a first typical example of the distribution state of oxygen atoms contained in the layer region (O) in the layer thickness direction. In the example shown in FIG. 2, from the interface position _tB where the surface where the layer region (O) containing oxygen atoms is formed and the surface of _the layer region (O) contact, the oxygen The layer region (O) where oxygen atoms are formed while the distribution concentration of atoms C is a constant value of _C1 .
The distribution concentration C is contained in the interface position t _T from position t ₁ .
It is gradually and continuously decreased from C ₂ up to . At the interface position _tT , the distribution concentration of oxygen atoms C
is assumed to be C ₃ . In the example shown in FIG. 3, the distribution concentration C of the contained oxygen atoms gradually and continuously decreases from C ₄ to position t _T from position t _B to position t _T.
A distribution state such as C ₅ is formed. In the case of Fig. 4, the distribution concentration C of oxygen atoms is constant at _C6 from position t _B to position t ₂ , and at position t ₂
It is gradually and continuously decreased between and the position _tT , and becomes substantially zero at the position _tT . In the case of Figure 5, the oxygen atom is located at a position lower than position t _B.
Until t _T , the distribution concentration C is gradually decreased continuously from C ₈ and becomes substantially zero at the position t _T . In the example shown in FIG. 6, the distribution concentration C of oxygen atoms is a constant value of _C9 between position _tB and position _t3 , and _C10 at position _tT . 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, the distribution concentration C takes a constant value of C ₁₁ from position t _B to position t ₄ , and at position t ₄
The distribution state decreases linearly from C ₁₂ to C ₁₃ up to position t _T . In the example shown in FIG. 8, from position t _B to position t _T
Up to , the distribution concentration C of oxygen atoms decreases linearly from C ₁₄ to zero. In FIG. 9, from position t _B to position t ₅ , the distribution concentration C of oxygen atoms decreases linearly from C ₁₅ to C ₁₆ , and between position t ₅ and t _T. , C ₁₆ are shown as constant values. In the example shown in FIG. 10, the distribution concentration C of oxygen atoms is C ₁₇ at position t _B , and from this C 17 it gradually decreases until reaching position t ₆ , and then the distribution concentration C of oxygen atoms decreases slowly from this C ₁₇ until reaching position t ₆ . , it is rapidly decreased to C ₁₈ at position t ₆ . Between position _t6 and position ₇ , the distribution concentration C
is decreased rapidly at first, and then slowly and gradually decreased to C ₁₉ at position t ₇ , and between positions t ₇ and t ₈ , it is decreased very gradually and gradually to position t ₈ . , reaching C ₂₀ . position t ₈ and position t _T
In between, the distribution concentration C is reduced from C ₂₀ to substantially zero according to a curve shaped as shown in the figure. As described above with reference to FIGS. 2 to 10, some typical examples of the distribution state of oxygen atoms contained in the layer region (O) in the layer thickness direction, in the present invention, on the support side , a layer region containing oxygen atoms in a distributed state, which has a portion where the distribution concentration C of oxygen atoms is high, and has a portion where the distribution concentration C is relatively lower on the interface _tT side than on the support side. (O) is provided in the amorphous layer. In the present invention, the layer region (O) containing oxygen atoms constituting the amorphous layer has a localized region A containing oxygen atoms at a relatively high concentration on the support side as described above. It is desirable that the amorphous layer is provided as having the support, and in this case, the adhesion between the support and the amorphous layer can be further improved. If the localized region A is explained using the symbols shown in FIGS. 2 to 10, it is preferable that the localized region A be provided within 5 μm from the interface position t _B. 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 is determined as appropriate depending on the characteristics required of the amorphous layer to be formed. Localized region A has a distribution state of oxygen atoms contained therein in the layer thickness direction, and the maximum value Cmax of the distribution concentration of oxygen atoms is usually 500 atomic ppm or more, preferably 800 atomic ppm or more, and optimally 1000 atomic ppm or more.
It is desirable that the layer be formed in such a way that it can have a distribution state of ppm or more. That is, in the present invention, the layer region (O) containing oxygen atoms has the maximum value of the distribution concentration C within 5 μm in layer thickness from the support side (layer region 5 μ thick from t _B ).
It is desirable that the structure be formed so that Cmax exists. In the present invention, the content of group atoms contained in the atom-containing layer region () may be appropriately determined as desired so as to effectively achieve the object of the present invention, but usually is 0.01~5×
10 ⁴ atomic ppm, preferably 0.5 to 1×10 ⁴ atomic
ppm, preferably 1 to 5×10 ³ atomic ppm. 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 raw material gas for supply, the raw material gas for introducing hydrogen atoms H and/or for introducing halogen atoms A layer made of a-Si(H,X) may be formed on the surface of a predetermined support placed at a certain position. In addition, when forming by sputtering method, Si is formed in an atmosphere of an inert gas such as Ar or He or a mixed gas based on these gases.
When sputtering a target composed of the following, it is sufficient to introduce a gas for introducing hydrogen atoms H and/or halogen atoms X into the deposition chamber for sputtering. In the present invention, the halogen atom X contained in the first amorphous layer () as necessary is as follows:
Specific examples include fluorine, chlorine, bromine, and iodine, with fluorine and chlorine being particularly preferred. 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, SiH ₄ and Si ₂ H ₆ are particularly preferred in terms of ease of layer preparation work and good Si supply efficiency. Effective raw material gases for introducing halogen atoms used in the present invention include many halogen compounds, such as halogen gases, halides, interhalogen compounds, halogen-substituted silane derivatives, etc. Preferred examples include halogen compounds that can be converted into 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 ₂ , 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 containing halogen atoms can be formed on a predetermined support. When forming 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 a 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. In particular, it is possible to form a first amorphous layer () on a given support, but in order to introduce hydrogen atoms, a silicon compound containing hydrogen atoms may be added to these gases. A predetermined amount of gas may also be mixed 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 plating 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 ,
Halogen-substituted silicon hydrides such as SiH ₂ I ₂ , SiH ₂ Cl ₂ , SiHCl ₂ , SiH ₂ Br ₂ , SiHBr ₃ , etc., and halides that have a hydrogen atom as one of their constituents in a gaseous state or can be gasified are also used. Effective first amorphous layer ()
It can be mentioned as a starting material for the formation. 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 atoms. In order to structurally introduce hydrogen atoms into the first amorphous layer (), in addition to the above, H ₂ or SiH ₄ ,
Silicon hydride gas such as Si ₂ H ₆ , Si ₃ H ₃ , Si ₄ H ₁₀ etc.
This can also be done by causing a discharge by coexisting in a deposition chamber with a silicon compound for supplying Si. 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 support. Furthermore, a gas such as B ₂ H ₆ can also be introduced for doping with impurities. In the present invention, the amount of hydrogen atoms H, the amount of halogen atoms X, or the sum of the amounts of hydrogen atoms and halogen atoms contained in the first amorphous layer () of the photoconductive member to be formed is in the normal case. It is desirable that the content be 1 to 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 What is necessary is to control the amount of starting materials used in the deposition system introduced into the deposition system, the discharge force, etc. In order to provide the first amorphous layer ( ) with a layer region ( ) containing group atoms and a layer region (O) containing oxygen atoms, the first non-crystalline layer ( ) is formed by a glow discharge method, a reactive sputtering method, etc. When forming the crystalline layer (), using a starting material for introducing group atoms and a starting material for introducing oxygen atoms together with the above-mentioned starting material for forming the first amorphous layer (), This is accomplished by controlling the amount of the compound contained in the formed layer. When a glow discharge method is used to form the layer region containing oxygen atoms (O) and the layer region containing group atoms () constituting the first amorphous layer (), each layer region is formed. The starting material that becomes the raw material gas for
The starting materials for the introduction of oxygen atoms and/or the starting materials for the introduction of group atoms are added to those selected as desired among the starting materials for the formation. Such starting materials for introducing oxygen atoms or starting materials for introducing group atoms include gaseous substances or gasified substances whose constituent atoms are at least oxygen atoms or group atoms. Most can be used. For example, if a layer region (O) is to be formed, a raw material gas containing silicon atoms Si, a raw material gas containing oxygen atoms O, and hydrogen atoms H or/and halogen atoms X as necessary are used. Either a raw material gas containing constituent atoms is mixed at a desired mixing ratio, or a raw material gas containing silicon atoms Si and a raw material gas containing oxygen atoms O and hydrogen atoms H are used. , which is also mixed at a desired mixing ratio, or by mixing a raw material gas containing silicon atoms, Si, and oxygen atoms, O.
and a source gas having three hydrogen atoms H as constituent atoms can be used in combination. 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, starting materials for introducing oxygen atoms include, for example, oxygen O ₂ , ozone O ₃ , nitrogen monoxide NO, nitrogen dioxide NO ₂ , nitrogen monooxide N ₂ O, nitrogen sesquioxide N ₂ O ₃ , Nitrogen tetroxide N ₂ O ₄ , nitrogen pentoxide N ₂ O ₅ , nitrogen trioxide NO ₃ , silicon atom Si, oxygen atom O, and hydrogen atom H as constituent atoms, such as disiloxane H ₃ SiOSiH ₃ , trioxide Examples include lower siloxanes such as siloxane H ₃ SiOSiH ₂ OSiH ₃ and the like. When the layer region () is formed using a glow discharge method, B ₂ H ₆ and B ₄ are effectively used in the present invention as starting materials for introducing group group atoms. H ₁₀ , B ₅ H ₉ , E ₅ H ₁₁ ,
Boron hydride such as B ₆ H ₁₀ , B ₆ H ₁₂ , B ₆ H ₁₄ , BF ₃ ,
Examples include boron halides such as BCl ₃ and BBr ₃ .
In addition, AlCl ₃ , GaCl ₃ , Ga(CH ₃ ) ₃ , InCl ₃ ,
TlCl ₃ etc. can also be mentioned. The content of group atoms introduced into the layer region ( ) containing group atoms is determined by the gas flow rate of the starting material for introducing group atoms introduced into the deposition chamber, the gas flow rate ratio, the discharge power, the support It can be arbitrarily controlled by controlling the temperature, the pressure inside the deposition chamber, etc. To form the layer region (O) containing oxygen atoms by the sputtering method, a monocrystalline or polycrystalline Si wafer or a SiO ₂ wafer, or a Si and
This can be carried out by sputtering a wafer containing a mixture of SiO ₂ 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 in the raw material gas shown in the glow discharge example mentioned above is
It can also be used as an effective gas in sputtering. In the present invention, the diluting gas used when forming the first amorphous layer () by a glow discharge method or the sputtering gas used when forming the first amorphous layer by a sputtering method includes: , so-called rare gases, such as He, Ne, Ar, etc., can be cited as preferred. 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. In the present invention, since each of the amorphous materials forming the first amorphous layer () and the second amorphous layer () have a common constituent element of silicon atoms, , chemical stability is sufficiently ensured at the laminated interface. The second amorphous layer () is an amorphous material (a-Si _X C _1-X ,
However, it is formed so that 0<X<1). a-Second amorphous layer composed of Si _X C _1-X ()
107 can be formed by sputtering method, ion implantation method, ion plating method,
This is done by an electron beam method or the like. 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. Sputtering has advantages such as it is relatively easy to control the manufacturing conditions for manufacturing photoconductive members, and it is easy to introduce carbon atoms together with silicon atoms into the amorphous layer (2). method, electron beam method, and ion plating method are preferably employed. To form the second amorphous layer () by the sputtering method, target a single crystal or polycrystalline Si wafer and a C wafer, or a wafer containing a mixture of Si and C. This can be done by sputtering in various gas atmospheres. For example, when using Si wafers and C wafers as targets, He, Ne, Ar
A sputtering gas such as the above may be introduced into a sputtering deposition chamber to form a gas plasma, and the Si wafer and C wafer may be sputtered. Alternatively, by using a single target containing a mixture of Si and C, a gas for sputtering is introduced into the equipment system, and sputtering is performed in the gas atmosphere. will be accomplished. When using the electron beam method, single-crystal or polycrystalline high-purity silicon and high-purity graphite are placed in two evaporation boats, and each is independently co-deposited by an electron beam or simultaneously deposited. Silicon and graphite placed in a boat at a desired mixing ratio may be deposited using a single electron beam. In the case of the former, the content ratio of silicon atoms and carbon atoms contained in the second amorphous layer ( ) is controlled by changing the accelerating voltage of the electron beam with respect to silicon and graphite; In this case, it is controlled by determining the amount of silicon and graphite mixed in advance. When using the ion plating method, various gases are introduced into the evaporation tank, and a high-frequency electric field is applied to a coil placed around the tank to generate a glow. Si and C are then deposited using the electron beam method. All you have to do is evaporate it. The second amorphous layer ( ) in the present invention is carefully formed so as to provide the desired properties. In other words, materials whose constituent atoms are Si and C can vary in structure from crystalline to amorphous depending on the conditions of their creation, and in terms of electrical properties, they can range from conductive to semiconductive to insulating. In the present invention, a-Si _X C _1-X having desired properties depending on the purpose is As it is formed,
The selection of the production conditions is made strictly according to desire. For example, in order to provide the second amorphous layer () with the main purpose of improving voltage resistance, a _{- Si} Created as. 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. a-Si _x C _1-X is produced as an amorphous material having a certain degree of sensitivity. When forming the second amorphous layer ( ) made of a-Si _X C _1-X on the surface of the first amorphous layer ( ), the temperature of the support during layer formation is It is an important factor that influences the structure and properties, and in the present _invention , the temperature of _the support at the time of layer formation is It is desirable that the In order to effectively achieve the purpose of the present invention, the temperature of the support when forming the second amorphous layer () should be adjusted according to the method of forming the second amorphous layer (). The second amorphous layer () is formed by appropriately selecting an optimal range, preferably 20 to 300°C,
The optimal temperature is preferably 20 to 250°C. In order to form the second amorphous layer (), sputtering is used because fine control of the composition ratio of atoms constituting the layer and control of the layer thickness are relatively easy compared to other methods. It is advantageous to adopt the zuttering method or the electron beam method, but 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. A discharge power of a
It can be cited as one of the important factors that influence the properties _{of -Si} The discharge power conditions for effectively producing a _{- Si}
250W, ideally 80W to 150W. 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 formation factors are not determined independently and separately, but rather the a-Si _X C _1-X
Preferably, the optimum value of each production factor is determined based on their mutual organic relationship so that a second amorphous layer () consisting of: The amount of carbon atoms contained in the second amorphous layer ( ) in the photoconductive member of the present invention achieves the object of the present invention, as do the conditions for producing the second amorphous layer ( ). This is an important factor in forming a layer that provides desired properties. The amount of carbon atoms contained in the second amorphous layer () in the present invention is usually 1×10 -3 to 1×10 ⁻³ based on the sum of silicon atoms and carbon atoms.
It is desirable that the content be 90 atomic %, preferably 1 to 80 atomic %, most preferably 10 to 75 atomic %. In other words, if we use the above representation of a-Si _X C _1-X ,
x is usually 0.1 to 0.99999, preferably 0.2 to 0.99, optimally 0.25 to 0.9. 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. Also, the layer thickness of the second amorphous layer () is determined depending on the amount of carbon atoms contained in the layer () and the layer thickness of the first amorphous layer (). It needs to be appropriately determined as desired based on organic relationships depending on the characteristics required for each layer region. In addition, it is desirable to take into consideration economic efficiency, which takes into account productivity and mass production. The layer thickness of the second amorphous layer ( ) in the present invention is usually 0.003 to 30μ, preferably 0.004 to 20μ,
The optimum value is 0.005 to 10μ. 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. . Preferably, at least one 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 metal, Conductivity is imparted to the surface. The shape of the support may be cylindrical, belt-like, plate-like, etc., and the shape is determined as desired. For example, the photoconductive member 100 in FIG. If used as a member for continuous high-speed 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 to 1106 in the diagram include
The raw material gas for forming each layer region of the present invention is sealed, and as an example, 11
02 is a SiH ₄ (purity 99.999%, hereinafter abbreviated as SiH ₄ /He) cylinder diluted with He, and 1103 is a B ₂ H ₆ gas diluted with He (purity 99.999%, below).
Abbreviated as B ₂ H ₆ /He. ) cylinder, 1104 is an Ar gas (purity 99.99%) cylinder, 1105 is a NO gas (purity 99.999%) cylinder, and 1106 is a SiF ₄ gas diluted with He (purity 99.999%, hereinafter abbreviated as SiF ₄ /He) cylinder. It is. 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 valves 1132 and 1133 and the outflow valves 1117 to 1 are closed.
Close 121. Next, an example will be given in which a photoconductive member having the layer structure shown in FIG. 1 is formed on the base 1137. SiH ₄ /He gas from gas cylinder 1102, gas cylinder 1
B ₂ H ₆ /He gas from 103, gas cylinder 110
5 to NO gas through valves 1122 and 112, respectively.
3,1125 open and outlet pressure gauge 1127,1
Adjust the pressure of 128 and 1130 to 1Kg/cm ² respectively,
Gradually open the inflow valves 1112, 1113, and 1115, respectively, and the mass flow controllers 1107,
1108 and 1110, respectively. Subsequently, the outflow valves 1117, 1118, 1120,
The auxiliary valve 1132 is gradually opened to allow each gas to flow into the reaction chamber 1101. At this time
The outflow valves 1117, 1118, and 1120 are adjusted so that the ratio of the SiH ₄ /He gas flow rate to the B ₂ H ₆ /He gas flow rate and NO gas flow rate becomes the desired value, and the pressure inside the reaction chamber is adjusted to the desired value. Vacuum gauge 11 to get the value
Adjust the opening of the main valve 1134 while checking the reading of 36. After confirming that the temperature of the base cylinder 1137 is set to a temperature in the range of 50 to 400°C by the heater 1138, the power source 1140 is set to the desired power to generate glow discharge in the reaction chamber 1101. At the same time, the flow rate of NO gas is gradually changed manually or by a method such as an externally driven motor by operating the valve 1120 according to a pre-designed rate of change curve to reduce the amount of oxygen contained in the layer formed. Controls the distribution concentration of atoms in the layer thickness direction. As described above, when the layer region (B, O) containing boron atoms and oxygen atoms is formed to the desired layer thickness, the outflow valves 1118 and 1120 are closed, and the B ₂ H into the reaction chamber 1101 is By continuing layer formation under the same conditions except for blocking the inflow of ₆ /He gas and NO gas, a desired layer region containing no oxygen atoms and boron atoms is formed on the layer region (B, O). The layer thickness is as follows. In this way, the first amorphous layer ( ) having desired characteristics can be formed on the substrate 1137. The layer region () containing boron atoms is configured to cut off the flow of B ₂ H ₆ /He gas into the reaction chamber 1101 at an appropriate point in the process of forming the first amorphous layer (). Accordingly, the layer can be formed to a desired thickness, and the layer region (O) can either occupy the entire layer region or a part of the layer region (O). For example, in the above example, the layer regions (B,
By continuing to form the layer under the same conditions, except for cutting off the inflow of NO gas into the reaction chamber 1101 by completely closing the outflow valve 1120, when O) has been formed to the desired layer thickness, layer area (B,
A layer region containing boron atoms but not oxygen atoms can be formed as part of the first amorphous layer (O). Further, when forming a layer region that does not contain boron atoms but contains oxygen atoms, the layer may be formed using, for example, NO gas and SiH ₄ /He gas. When containing halogen atoms in the first amorphous layer ( ), for example, SiF ₄ /He is added to the above gas.
is further added and sent into the reaction chamber 1101. To form the second amorphous layer ( ) on the first amorphous layer ( ), for example, the following procedure is performed.
First, open shutter 1142. All gas supply valves are once closed, and the reaction chamber 1101 is evacuated by fully opening the main valve 1134. A target in which a high-purity silicon wafer 1142-1 and a high-purity graphite wafer 1142-2 are placed in a desired area ratio is provided in advance on the electrode 1141 to which high-voltage power is applied. Ar gas is supplied from the gas cylinder 1104 to the reaction chamber 1101.
The internal pressure of the reaction chamber 1101 is 0.05~
Adjust the main valve 1134 so that the pressure is 1 torr. By turning on the high voltage power supply 1140 and sputtering the target, a second amorphous layer () can be formed on the first amorphous layer (). The amount of carbon atoms contained in the second amorphous layer (2) is determined by the sputter area ratio of the silicon wafer 1142-1 and the graphite wafer 1142-2, and the amount of silicon powder and graphite powder used to create the target. can be controlled as desired by adjusting the mixing ratio 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 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 equipment shown in Fig. 11, the first and second
An imaging member having an oxygen concentration distribution as shown in FIG. 12 in the region layer was prepared under the conditions shown in Table 1. The image forming member thus obtained was placed in a charging exposure experimental device, corona charged at 5.0 kV for 0.2 seconds, and immediately irradiated with a light image. The optical image was generated using a tungsten lamp light source, and a light intensity of 1.5 ux·sec was irradiated through 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. When the toner image on the member was transferred onto transfer paper using 5.0kV corona charging, a clear, high-density image with excellent resolution and good gradation reproducibility was obtained.

[Table] Example 2 Using the manufacturing equipment shown in Fig. 11, the first and second
An imaging member having an oxygen distribution concentration in the layer as shown in FIG. 13 was prepared under the conditions shown in Table 2. Other conditions were the same as in Example 1. Using the thus obtained image forming member, an image was formed on a transfer paper under the same conditions and procedures as in Example 1, and an extremely clear image quality was obtained.

[Table] Example 3 Using the manufacturing apparatus shown in FIG. 11, an image forming member having an oxygen distribution concentration as shown in FIG. 5 in the first layer was produced under the conditions shown in Table 3. Other conditions were the same as in Example 1.
Regarding the image forming member thus obtained, Example 1
When an image was formed on transfer paper under the same conditions and procedures as described above, an extremely clear image quality was obtained.

[Table] Example 4 When forming the amorphous layer (), the area ratio of the silicon wafer and graphite was changed to increase the content ratio of silicon atoms and carbon atoms in the amorphous layer (). An image forming member was prepared in the same manner as in Example 3 except for the following changes. After repeating the image forming, developing, and cleaning steps as described in Example 1 approximately 50,000 times for the image forming member thus obtained, image evaluation was performed.
The results shown in the table were obtained.

[Table] ◎〓Very good ○〓Good △〓Sufficient for practical use
x Example 5 where image defects are likely to occur An image forming member was prepared in the same manner as in Example 1 except that the thickness of the amorphous layer ( ) was changed. The steps of image formation, development, and cleaning as described in Example 1 were repeated to obtain the following results.

[Table] Example 6 Layers were formed in the same manner as in Example 1, except that the method of forming the first and second layers was changed as shown in the table below.
When image quality was evaluated in the same manner as in Example 1, good results were obtained.

【table】 [Brief explanation of drawings]

FIG. 1 is a schematic layer configuration diagram for explaining the layer configuration of the photoconductive member of the present invention, and FIGS. 2 to 10 are layer regions containing oxygen atoms (O ), FIG. 11 is a schematic explanatory diagram of the apparatus used in the present invention, and FIGS. 12 to 14 are diagrams for explaining the distribution state of oxygen atoms in the present invention. FIG. 100...Photoconductive member, 101...Support, 102
...first amorphous layer (), 103...first layer region (O), 104...second layer region (), 105...upper layer region, 106...second amorphous layer (), 10
7...Free surface.

Claims (1)

[Claims] 1. A support for a photoconductive member for electrophotography, a first amorphous layer having photoconductivity and having a layer thickness of 1 to 100 μm and made of an amorphous material having silicon atoms as a matrix, and silicon atoms. and 1×10 ^-3 ~90 atomic% carbon atoms.
and a second amorphous layer with a thickness of 0.003 to 30μ, and the first amorphous layer has a thickness of 0.001 to 30μ as constituent atoms.
A first layer region containing 50 atomic% of oxygen atoms and in contact with the support and occupying a part of the first amorphous layer and 0.01 to 5×10 ⁴ atoms as constituent atoms.
a second layer region having a layer thickness of 50 μm or less containing atoms belonging to Group 1 of the Periodic Table of ppm, and a portion where the oxygen atom distribution state is higher than 500 atomic ppm on the support side; and a non-uniform and continuous distribution state in the layer thickness direction with a portion lowered on the second amorphous layer side than on the support side, and the layer thickness of the second layer region T _B and a layer thickness T obtained by subtracting the layer thickness T _B of the second layer region from the layer thickness of the first amorphous layer.
A photoconductive member for electrophotography, characterized in that T _B /T≦1.