JPH0211148B2 - - 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 spectral characteristics that match the spectral characteristics of the irradiated electromagnetic waves, have fast photoresponsiveness, and have the desired dark resistance value. In some cases, solid-state imaging devices are required to have characteristics such as being harmless to the human body and being able to easily process afterimages within a predetermined time. In particular, 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 harmlessness 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. The application as an image forming member for photography and the application to a photoelectric conversion/reading device are described in German Published Publication No. 2933411. However, the conventional photoconductive member for electrophotography having a photoconductive layer composed of a-Si has a dark resistance value,
It is necessary to improve the overall properties in terms of electrical, optical, and photoconductive properties such as photosensitivity and photoresponsiveness, use environment properties such as moisture resistance, and stability over time. The reality is that there are points that can be further improved. For example, when applied to an electrophotographic image forming member, when trying to achieve high photosensitivity and high dark resistance at the same time, in the past, it was often observed that residual potential remained during use. When a conductive member is used repeatedly for a long period of time, fatigue accumulates due to repeated use, resulting in the so-called ghost phenomenon that causes an afterimage, or when used repeatedly at high speeds, the response gradually decreases. There were many cases where spots appeared. Furthermore, a-Si has a relatively smaller absorption coefficient in the long wavelength region than in the short wavelength region of the visible light region, which makes it difficult to match with semiconductor lasers currently in practical use. Furthermore, when a commonly used halogen lamp or fluorescent lamp is used as a light source, there remains room for improvement in that it is not possible to effectively use light on the longer wavelength side. In addition, if the irradiated light is not absorbed sufficiently in the photoconductive layer and the amount of light that reaches the support increases, the support itself will absorb the light that passes through the photoconductive layer. When the reflectance is high, interference due to multiple reflections occurs within the photoconductive layer, which is one of the causes of "blurring" of images. This effect becomes greater as the irradiation spot is made smaller in order to increase the resolution, and is a major problem especially when a semiconductor laser is used as the light source. Furthermore, 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 Boron atoms, phosphorus atoms, etc. are contained in the photoconductive layer as constituent atoms to control the properties of the photoconductive layer, and other atoms are included in the photoconductive layer to improve properties. In some cases, problems may arise with 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. Furthermore, if the layer thickness exceeds 10 microns or more, the layer may lift or peel off from the surface of the support, or cracks may develop as the time passes for the layer to stand in the air after being removed from the vacuum deposition chamber for layer formation. It was a victory because it brought about phenomena such as this. This phenomenon often occurs especially when the support is a drum-shaped support commonly used in the field of electrophotography, and should be solved in terms of stability over time. . 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. 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, solid-state imaging devices, reading devices, etc., we found that silicon atoms an amorphous material containing at least either a hydrogen atom (H) or a halogen atom (X),
A photoconductive material composed of so-called hydrogenated amorphous silicon, halogenated amorphous silicon, or halogen-containing hydrogenated amorphous silicon (hereinafter, "a-Si(H,X)" will be used as a general term for these). A photoconductive member designed and produced by specifying the structure of a photoconductive member having a photoreceptive layer exhibiting properties as described below not only exhibits extremely superior properties in practical use, but also exhibits superior properties compared to conventional photoconductive members. It is superior in all respects when compared to other materials, has particularly excellent properties as a photoconductive material for electrophotography, and has excellent absorption spectrum characteristics on the long wavelength side. It is based on what was discovered. The present invention has stable electrical, optical, and photoconductive properties at all times, is suitable for all environments with almost no restrictions on usage environments, and has excellent photosensitivity on the long wavelength side and is extremely resistant to light fatigue. The main object of the present invention is to provide a photoconductive member for electrophotography that has a long lifespan, does not cause any deterioration phenomenon even after repeated use, and has no or almost no residual potential observed. Another object of the present invention is to provide a photoconductive member for electrophotography that has high photosensitivity in the entire visible light range, has excellent matching with semiconductor lasers in particular, and has fast photoresponse. Another object of the present invention is to provide excellent adhesion between a layer provided on a support and the support and between each laminated layer, to provide a dense and stable structural arrangement, and to provide layer quality. It is an object of the present invention to provide a photoconductive member for electrophotography having high properties. Another object of the present invention is to maintain charge retention during charging processing for electrostatic image formation to such an extent that ordinary electrophotography can be applied very effectively when applied as an image forming member for electrophotography. It is an object of the present invention to provide a photoconductive member having excellent electrophotographic properties with sufficient performance and with almost no deterioration of the properties observed even in a humid atmosphere. 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 for electrophotography that has high signal-to-noise ratio characteristics and good electrical contact with a support. The photoconductive member for electrophotography of the present invention includes a support for the photoconductive member for electrophotography, and on the support, germanium atoms are added in an amount of 1 to 10 with respect to the sum of silicon atoms.
A first layer region (G) with a layer thickness of 30 Å to 50 μ made of an amorphous material containing ×10 ⁵ atomic ppm and a layer made of an amorphous material containing silicon atoms (but not containing germanium atoms) A photoconductive member for electrophotography, comprising a second layer region (S) having a thickness of 0.5 to 90μ and a photoreceptive layer exhibiting photoconductivity having a layer structure of 1 to 100μ and provided in order from the support side. The photoreceptive layer is characterized in that nitrogen atoms are contained in the amount of 0.001 to 50 atomic %. The electrophotographic photoconductive member of the present invention designed to have the above-described layer structure can solve all of the above-mentioned problems, and has extremely excellent electrical, optical, and photoconductive properties. , shows electrical voltage resistance and operating 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. Further, in the electrophotographic photoconductive member of the present invention, the photoreceptive layer formed on the support is strong and has excellent adhesion to the support.
Can be used repeatedly and continuously at high speed for long periods of time. Furthermore, the photoconductive member for electrophotography of the present invention has high photosensitivity in the entire visible light range, is particularly excellent in matching with semiconductor lasers, and has fast optical response. DESCRIPTION OF THE PREFERRED EMBODIMENTS The electrophotographic photoconductive member of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a diagram schematically showing the layer structure of a photoconductive member according to a first embodiment of the present invention. A photoconductive member 100 shown in FIG. 1 has a support 101 for the photoconductive member and a photoreceptive layer 102 on the support 101, and the photoreceptor layer 102 has a free surface 105 as one end surface. has. The light-receiving layer 102 is made of an amorphous material (hereinafter referred to as "a-Ge ( Si,H,
The first layer region (G) composed of
103 and a second layer region (S) 104 made of a-Si (H, X) and having photoconductivity are laminated in this order. When germanium atoms are contained together with other atoms in the first layer region (G) 103, silicon atoms are present in the layer thickness direction of the first layer region (G) 103 and in the support body 101. It is contained in the first layer region (G) 103 so as to be continuously and uniformly distributed in the in-plane direction parallel to the surface. In the present invention, germanium atoms are not contained in the second layer region (S) provided on the first layer region (G), and a light-receiving layer is not provided in such a layer structure. By forming such a photoconductive member, it is possible to obtain a photoconductive member that has excellent photosensitivity to light in the entire wavelength range from relatively short wavelengths to relatively long wavelengths, including the visible light region. In addition, the distribution state of germanium atoms in the first layer region (G) is such that germanium atoms are continuously distributed in the entire layer region, so the distribution state of germanium atoms in the first layer region (G) and the second layer region (G) are
It has excellent affinity with the layer region (S) of In the layer region (G), substantially complete absorption can be achieved, and interference due to reflection from the support surface can be prevented. Further, in the electrophotographic photoconductive member of the present invention,
When silicon atoms are contained in the first layer region (G), each of the light-receiving materials constituting the first layer region (G) and the second layer region (S) has a common structure of silicon atoms. Because of the presence of these elements, chemical stability is sufficiently ensured at the laminated interface. In the present invention, the content of germanium atoms contained in the first layer region (G) is appropriately determined as desired so that the object of the present invention is effectively achieved, but preferably 1 to 10×10 ⁵ atomic ppm, more preferably 100 to
9.5× ¹⁰⁵ atomic ppm, optimally 500–8×
It is desirable to set it to 10 ⁵ atomic ppm. In the present invention, the layer thickness of the first layer region (G) and the second layer region (S) is one of the important factors for effectively achieving the object of the present invention, so the formation Considerable care must be taken in the design of the photoconductive member to ensure that the desired properties are fully imparted to the photoconductive member. In the present invention, the layer thickness T _B of the first layer region (G) is
Preferably 30 Å to 50 μ, more preferably 40 Å
It is desirable that the thickness be ˜40 μ, optimally 50 Å to 30 μ. Further, the layer thickness T of the second layer region (S) is preferably 0.5 to 90μ, preferably 1 to 80μ, and optimally 2
It is desirable that the thickness be ~50μ. Layer thickness T _B of the first layer region (G) and second layer region (S)
The sum of the layer thicknesses T (T _B +T) is calculated based on the layer design of the photoconductive member based on the organic relationship between the characteristics required for both layer regions and the characteristics required for the entire photoreceptive layer. It is determined as appropriate in accordance with the requirements. In the photoconductive member of the present invention, the above (T _B
The numerical range of +T) is preferably 1 to 100μ,
More preferably, it is 1 to 80μ, most preferably 2 to 50μ. In a more preferred embodiment of the present invention,
The above layer thickness T _B and layer thickness T are preferably
When satisfying the relationship T _B /T≦1, it is desirable to select appropriate numerical values for each. In selecting the numerical values of the layer thickness T _B and the layer thickness T in the above case, it is more preferable that T _B /T≦0.9,
Optimally, it is desirable that the values of layer thickness T _B and layer thickness T be determined so that the relationship T _B /T≦0.8 is satisfied. In the present invention, the content of germanium atoms contained in the first layer region (G) is 1×10 ⁵ atomic
In the case of ppm or more, T _B of the first layer region (G) is
It is desirable to be as thin as possible, preferably 30μ
Hereinafter, it is more preferably 25μ or less, optimally 20μ or less. In the photoconductive member for electrophotography of the present invention, for the purpose of increasing photosensitivity and dark resistance, as well as improving the adhesion between the support and the photoreceptive layer, contains a nitrogen atom. The nitrogen atoms contained in the photoreceptive layer may be uniformly contained in the entire layer area of the photoreceptive layer, or may be contained and unevenly distributed only in some layer areas of the photoreceptive layer. . In addition, the distribution state of nitrogen atoms is the distribution concentration C(N)
may be uniform in the layer thickness direction of the photoreceptive layer, or may be non-uniform in the layer thickness direction. In the present invention, when the main purpose of the layer region (N) containing nitrogen atoms provided in the photoreceptive layer is to improve photosensitivity and dark resistance, the entire layer region of the photoreceptive layer is If the main purpose is to strengthen the adhesion between the support and the photoreceptive layer, it is provided so as to occupy the end layer region (E) of the photoreceptor layer on the side of the support. You can get caught. In the former case, the content of nitrogen atoms contained in the layer region (N) is kept relatively low in order to maintain high photosensitivity, while in the latter case, it ensures enhanced adhesion with the support. It is desirable to have a relatively large amount for measurement purposes. In addition, in order to achieve both the former and the latter at the same time, it is necessary to distribute the concentration at a relatively high concentration on the support side and at a relatively low concentration on the free surface side of the photoreceptive layer, or In the surface layer region on the free surface side of the light-receiving layer, a nitrogen atom distribution state may be formed in the layer region (N) such that nitrogen atoms are not actively contained. In the present invention, the content of nitrogen atoms contained in the layer region (N) provided in the photoreceptive layer depends on the characteristics required for the layer region (N) itself, or when the layer region (N) is attached to the support. When provided in direct contact with the support, it can be appropriately selected depending on the organic relationship, such as the relationship of characteristics at the contact interface with the support. In addition, when another layer region is provided in direct contact with the layer region (N), the relationship with the characteristics of the other layer region and the characteristics at the contact interface with the other layer region The nitrogen atom content is appropriately selected with consideration given to the following. The amount of nitrogen atoms contained in the layer region (N) is determined as desired depending on the properties required of the photoconductive member to be formed, but is preferably 0.001 to 50 atomic %, more preferably 0.001 to 50 atomic %. 0.002
~40atomic%, optimally 0.003~30atomic%
It is desirable that this is done. In the present invention, whether the layer region (N) occupies the entire area of the photoreceptive layer or even if it does not occupy the entire area of the photoreceptor layer, the layer thickness of the photoreceptor layer is equal to the layer thickness T _N of the layer area (N). When the proportion of T is sufficiently large, the upper limit of the content of nitrogen atoms in the layer region (N) is
It is desirable that it be sufficiently smaller than the above value. In the case of the present invention, the ratio of the layer thickness T _N of the layer region (N) to the layer thickness T of the photoreceptive layer is two-fifths.
In such a case, the upper limit of the amount of nitrogen atoms contained in the layer region (N) is preferably
30atomic% or less, more preferably 20atomic%
% or less, preferably 10 atomic % or less. 2 to 10 show typical examples of the distribution state of nitrogen atoms contained in the layer region (N) of the photoconductive member in the present invention in the layer thickness direction. In Figures 2 to 10, the horizontal axis represents the nitrogen atom distribution concentration C (N), the vertical axis represents the layer thickness of the layer region (N), and t _B represents the layer region (N) on the support side. The position of the end surface, t _T , indicates the position of the end surface of the layer region (N) on the opposite side to the support side. That is, the layer region (N) containing nitrogen atoms is formed as a layer from the t _B side toward the t _T side. FIG. 2 shows a first typical example of the distribution state of nitrogen atoms contained in the layer region (N) in the layer thickness direction. In the example shown in FIG. 2, from the interface position tB where the surface of the support where the layer region (N) containing nitrogen atoms is formed and the surface of the layer region (N) contact, to _the position _t1 . is contained in the layer region (N) where nitrogen atoms are formed, while the distribution concentration C (N) of nitrogen atoms takes a constant value of C ₁ , and the concentration from position t ₁ to C ₂ to the interface position t _T. has been gradually and continuously reduced. At the interface position _tT , the distribution concentration of nitrogen atoms C
(N) is assumed to be C ₃ . In the example shown in FIG. 3, the distribution concentration C(N) of the contained nitrogen atoms is greater than _the position _t
A distribution state is formed in which the concentration gradually and continuously decreases from C ₄ until it reaches C ₅ at position t _T . In the case of Fig. 4, the distribution concentration C of nitrogen atoms is kept at a constant value _C6 from position _tB to position _t2 ,
Between position _t2 and position _tT , the distribution concentration C(N) is gradually and continuously decreased, and at position _tT , the distribution concentration C(N) is substantially zero (here, substantially zero is defined as detection). (if the amount is less than the limit amount). In the case of Fig. 5, the distribution concentration of nitrogen atoms C(N)
is continuously and gradually decreased from the concentration _C8 from the position _tB to the position _tT , and becomes substantially zero at the position _tT . In the example shown in FIG. 6, the distribution concentration C(N) of nitrogen atoms is a constant value of _C9 between position _tB and position _t3 , and the concentration _C10 at position _tT .
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, the distribution concentration C
(N) takes a constant value of concentration C ₁₁ from position t _B to position t ₄ , and from position t ₄ to position t _T , the concentration is higher than C ₁₂ .
It is said that the distribution state decreases linearly up to C ₁₃ . In the example shown in FIG. 8, from position t _B to position t _T
The distribution concentration C(N) of nitrogen atoms is the concentration
From C ₁₄ , it decreases linearly to virtually zero. In FIG. 9, from position t _B to position t ₅ , the distribution concentration C(N) of nitrogen atoms decreases linearly from the concentration C ₁₅ to the concentration C ₁₆ , and from position t ₅ to position t _T An example is shown in which the concentration C ₁₆ is set to a constant value. In the example shown in FIG. 10, the distribution concentration C(N) of nitrogen atoms is a concentration C ₁₇ at position t _B , and is gradually decreased from this concentration C ₁₇ until reaching position t ₆ , Near the position of t ₆ ,
It is rapidly decreased to a concentration _C18 at position _t6 . Between position t ₆ and position t ₇ , the concentration is decreased rapidly at first, then slowly and gradually decreased to reach C ₁₉ at position t ₇ , and then between position t ₇ and position t ₈ Then, the concentration is gradually decreased very slowly to reach the concentration C ₂₀ at position t ₅ . Between position _t8 and position _tT , the concentration is reduced from _C20 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 nitrogen atoms contained in the layer region (N) in the layer thickness direction, in the present invention, on the support side , a nitrogen atom distribution state having a portion where the distribution concentration C(N) of nitrogen atoms is high, and having a portion where the distribution concentration C(N) is considerably lower on the interface _tT side than on the support side. is provided in the layer region (N). In the present invention, the layer region (N) containing nitrogen atoms constituting the photoreceptive layer is the localized region (B) containing nitrogen atoms at a relatively high concentration on the support side as described above. It is desirable that the support be provided as having the following properties, and in this case, the adhesion between the support and the light-receiving layer can be further improved. If the localized region (B) is explained using the symbols shown in FIGS. 2 to 10, it is desirable that the localized region (B) be provided within 5 μm from the interface position t _B. In the present invention, the localized region (B) may be the entire layer region (L _T ) up to 5μ thick from the interface position t _B , or may be a part of the layer region (L _T ). In some cases, it may be done. Whether the localized region is a part or all of the total layer region (L _T ) is determined as appropriate depending on the characteristics required of the photoreceptive layer to be formed. The localized region (B) has a nitrogen atom distribution concentration C as the distribution state of oxygen atoms contained therein in the layer thickness direction.
The maximum value C _nax of (N) is preferably 500 atomic
ppm or more, more preferably 800 atomic ppm or more,
Optimally, it is desirable to form a layer so that a distribution state of 1000 atomic ppm or more can be achieved. That is, in the present invention, the layer region (N) containing nitrogen atoms has the maximum value C of the distribution concentration C (N) within 5 μm in layer thickness from the support side (layer region 5 μ thick from T _B ). It is desirable that the formation be such that _nax is present. In the present invention, the halogen atoms (X) optionally contained in the first layer region (G) and second layer region (S) constituting the photoreceptive layer include fluorine atoms. , chlorine, bromine, and iodine, with fluorine and chlorine being particularly preferred. 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 layer region (G) composed of a-Ge (Si, H, X). It is made by a vacuum deposition method. By glow discharge method, a-
To form the first layer region (G) composed of Ge (Si, H, X), for example, germanium atoms (Ge)
A raw material gas for Ge supply that can supply silicon atoms (Si), and a raw material gas for introducing hydrogen atoms (H) or/as needed.
and introducing a raw material gas for introducing halogen atoms (X) into a deposition chamber whose interior can be reduced in pressure at a desired gas pressure to generate a glow discharge within the deposition chamber;
It is sufficient to form a layer on the surface of a predetermined support that has been placed in advance at a predetermined position. When germanium atoms are contained in the first layer region (G) with a non-uniform concentration distribution, the distribution concentration of germanium atoms is controlled according to a desired rate of change curve, and a-Ge (Si, H, ) may be formed. In addition, when forming by sputtering method, for example, a target made of Si or a combination of the target and Ge in an atmosphere of an inert gas such as Ar or He or a mixed gas based on these gases. Using two targets or a mixed target of Si and Ge, feed the raw material gas for Ge supply diluted with diluent gas such as He or Ar as necessary. This is accomplished by introducing a gas for introducing hydrogen atoms (H) and/or halogen atoms (X) into a sputtering deposition chamber to form a plasma atmosphere of the desired gas. At this time, the distribution concentration of germanium atoms in the first layer region (G) can be adjusted arbitrarily by sputtering the target while controlling the gas flow rate of the raw material gas for supplying Ge according to a desired rate of change curve. It can be controlled. In the case of the ion plating method, for example, polycrystalline silicon or single crystal silicon and polycrystalline germanium or single crystal germanium are housed in a deposition boat as evaporation sources, and the evaporation sources are heated using a resistance heating method or an electron beam. Law (EB Law)
This can be carried out in the same manner as in the sputtering method, except that the evaporated matter is heated and evaporated by a method such as the like, and the flying evaporated material is passed through a desired gas plasma atmosphere. Substances that can be used as raw material gas for supplying Si used in the present invention include SiH ₄ , Si ₂ H ₆ , Si ₃ H ₈ ,
Gaseous or gasifiable silicon hydride (silanes) such as Si ₄ H ₁₀ can be effectively used, especially because of its ease of handling during layer creation work and good Si supply efficiency. In this respect, SiH ₄ and Si ₂ H ₆ are preferred. Substances that can be used as raw material gas for Ge supply include
_GeH4 , _{Ge2H6 , Ge3H8 , Ge4H10 , Ge5H12 ,}
Ge ₆ H ₁₄ , Ge ₇ H ₁₆ , Ge ₈ H ₁₈ , Ge ₉ H ₂₀ and other germanium hydrides in a gaseous state or which can be gasified are mentioned as those which can be effectively used, especially in layer forming operations. GeH ₄ , Ge ₂ H ₆ , and Ge ₃ H ₈ are preferred in terms of ease of handling, good Ge supply efficiency, and the like. 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 hydride 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 using a glow discharge method using such a silicon compound containing a halogen atom, the material gas that can supply Si together with the material gas for supplying Ge is used. The first layer region (G) made of a-SiGe containing halogen atoms can be formed on a desired support without using silicon hydride gas. When creating the first layer region (G) containing halogen atoms according to the glow discharge method, for example, silicon halide, which will be the raw material gas for supplying Si, germanium hydride, which will be the raw material gas for Ge supply, and Ar. , H ₂ , He
etc. are introduced into the deposition chamber forming the first layer region (G) at a predetermined mixing ratio and gas flow rate,
The first layer region (G) can be formed on the desired support by generating a glow discharge and forming a plasma atmosphere of these gases, but the introduction ratio of hydrogen atoms is In order to further facilitate control, a desired amount of hydrogen gas or 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. 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 form a plasma atmosphere of the gas. In addition, when introducing hydrogen atoms, a raw material gas for introducing hydrogen atoms, for example, H ₂ or gases such as the above-mentioned silanes and/or germanium hydride, is introduced into the deposition chamber for sputtering. It is sufficient to form a plasma atmosphere of the gases. 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 and HI, SiH ₂ F ₂ ,
Halogen-substituted silicon hydrides such as SiH ₂ I ₂ , SiH ₂ Cl ₂ , SiHCl ₃ , SiH ₂ Br ₂ , SiHBr ₃ , and GeHF ₃ ,
_GeH2F2 , _GeH3F , _{GeHCl3 , GeH2Cl2 ,
GeH3Cl} , _GeHBr3 , _GeH2Br2 , _{GeH3Br ,}
GeHI ₃ , GeH ₂ I ₂ , GeH ₃ I and other hydrogenated germanium halides, halides containing a hydrogen atom as one of their constituents, GeF ₄ , GeCl ₄ , GeBr ₄ ,
Germanium halides such as GeI ₄ , GeF ₂ , GeCl ₂ , GeBr ₂ , GeI ₂ and other gaseous or gasifiable substances may also be mentioned as effective starting materials for forming the first layer region (G). I can do it. Among these substances, halides containing hydrogen atoms are hydrogen atoms that are extremely effective in controlling electrical or photoelectric properties at the same time as introducing halogen atoms into the layer when forming the first layer region (G). Since halogen is also introduced, it is used as a suitable raw material for halogen introduction in the present invention. In order to structurally introduce hydrogen atoms into the first layer region (G), in addition to the above, H ₂ , SiH ₄ , Si ₂ H ₆ ,
Silicon hydride such as Si ₃ H ₈ , Si ₄ H ₁₀ and germanium or a germanium compound for supplying Ge, or GeH ₄ , Ge ₂ H ₆ , Ge ₃ H ₈ , Ge ₄ H ₁₀ ,
Germanium hydride such as Ge ₅ H ₁₂ , Ge ₆ H ₁₄ , Ge ₇ H ₁₆ , Ge ₈ H ₁₈ , Ge ₉ H ₂₀ , etc. and silicon or a silicon compound for supplying Si are allowed to coexist in the deposition chamber. This can also be done by causing electrical discharge. In a preferred example of the present invention, the amount of hydrogen atoms (H) or the amount of halogen atoms (X) or the amount of hydrogen atoms and halogen atoms contained in the first layer region (G) constituting the photoreceptive layer to be formed The sum of the amounts (H+X) is preferably 0.01 to 40 atomic%, more preferably 0.05
~30atmic%, optimally 0.1~25atmic%. In order to control the amount of hydrogen atoms (H) and/or halogen atoms (X) contained in the first layer region (G), for example, the support temperature or/and the hydrogen atoms (H) or halogen atoms The amount of the starting material used to contain (X) introduced into the deposition system, the discharge force, etc. may be controlled. In the present invention, in order to form the second layer region (S) composed of a-Si (H, Than,
When forming the first layer region (G) using the starting material [starting material for forming the second layer region (S)] excluding the starting material that becomes the raw material gas for supplying Ge; It can be carried out according to similar methods and conditions. That is, in the present invention, in order to form the second layer region (S) composed of a-Si (H, This is accomplished by using a vacuum deposition method. For example, by the glow discharge method, a second
In order to form the layer region (S), basically, in addition to the above-mentioned raw material gas for supplying Si that can supply silicon atoms (Si), a gas for introducing hydrogen atoms (H) or/and A raw material gas for introducing halogen atoms (X) is introduced into a deposition chamber whose interior can be reduced in pressure,
A glow discharge is generated in the deposition chamber, and a-Si is deposited on the surface of a predetermined support that has been placed at a predetermined position.
A layer consisting of (H, X) may be formed. or,
For example, when forming by sputtering method,
When sputtering a target composed of Si in an atmosphere of an inert gas such as Ar or He or a mixed gas based on these gases, it is necessary to introduce hydrogen atoms (H) and/or halogen atoms (X). Gas may be introduced into the deposition chamber for sputtering. In the photoconductive member of the present invention, the second layer region (S) provided on the first layer region (G) containing germanium atoms and not containing germanium atoms has conductive properties. By including a controlling substance, the conductive properties of the layer region (S) can be controlled as desired. Such substances include so-called impurities in the semiconductor field, and in the present invention, a-Si(H,X) constituting the second layer region (S) to be formed On the other hand, p-type impurities that give p-type conductivity characteristics and n-type impurities that give n-type conduction characteristics can be mentioned. Specifically, p-type impurities include atoms belonging to the group of the periodic table (group atoms), such as B (boron), Al (aluminum), Ga (gallium), In (indium), and Tl (thallium). ), among which B and Ga are particularly preferably used. Examples of n-type impurities include atoms belonging to a group of the periodic table (group atoms), such as P (phosphorus), As (arsenic), Sb (antimony), Bi (bismuth), etc. P and As are used. In the present invention, the content of the substance controlling the conduction properties contained in the second layer region (S) is determined based on the conduction properties required for the layer region (S) or the content of the substance controlling the conduction properties contained in the second layer region (S). It can be selected as appropriate based on the organic relationship, such as the characteristics of other layer regions provided in direct contact and the relationship with the characteristics at the contact interface with the other layer regions. In the present invention, the content of the substance controlling conduction properties contained in the second layer region (S) is preferably 0.001 to 1000 atomic ppm, more preferably 0.001 to 1000 atomic ppm.
0.05-500atomic ppm, optimally 0.1-200atomic
Preferably in ppm. In order to structurally introduce a substance controlling the conduction properties into the second layer region (S), for example a group atom or a group atom, a starting material for introducing a group atom during layer formation, Alternatively, the starting material for introducing group atoms may be introduced in gaseous form into the deposition chamber together with other starting materials for forming the second layer region. Possible starting materials for such introduction of group atoms include materials that are gaseous at room temperature and pressure, or
It is desirable to use a material that can be easily gasified at least under layer-forming conditions. Specifically, starting materials for introducing such group atom include B ₂ H ₆ , B ₄ H ₁₀ , B ₅ H ₉ , B 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. In the present invention, starting materials for introducing group atoms that are effectively used include hydrogenated phosphorus such as PH ₃ and P ₂ H ₄ , PH ₄ I, PF ₃ ,
Examples include phosphorus halides such as _PF5 , _PCl3 , _PCl5 , _PBr3 , _PBr5 , and _PI3 . In addition, AsH ₃ , AsF ₃ ,
AsCl ₃ , AsBr ₃ , AsF ₅ , SbH ₃ , SbF ₃ , SbF ₅ ,
SbCl ₃ , SbCl ₅ , BiH ₃ , BiCl ₃ , BiBr ₃ and the like can also be mentioned as effective starting materials for the group atom introduction family. In the present invention, in order to provide a layer region (N) containing nitrogen atoms in the photoreceptive layer, when forming the photoreceptive layer, a starting material for introducing nitrogen atoms is added to the above-mentioned photoreceptive layer forming material. It may be used together with the starting materials and contained in the layer to be formed while controlling its amount. When a glow discharge method is used to form the layer region (N), a starting material for introducing nitrogen atoms is added to a material selected as desired from among the starting materials for forming the photoreceptive layer described above. It will be done. As the starting material for introducing nitrogen atoms, most of the gaseous substances containing at least nitrogen 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 nitrogen atoms (N), and hydrogen atoms (H) or halogen atoms (X) as necessary. Either a raw material gas is mixed 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 nitrogen atoms (N) and hydrogen atoms (H) are used. These can also be used by mixing them in a desired mixing ratio. Also, separately, silicon atoms (Si) and hydrogen atoms (H)
You may mix and use the raw material gas which has an oxygen atom (O) as a constituent atom with the raw material gas whose constituent atoms are . The starting material that can be effectively used as a raw material gas for introducing nitrogen atoms (N) used when forming the layer region (N) is one containing N as a constituent atom or containing N and H. Gaseous or gasifiable, such as nitrogen (N ₂ ), ammonia (NH ₃ ), hydrazine (H ₂ NNH ₂ ), hydrogen azide (NH ₃ ), ammonium azide (NH ₄ N ₃ ), etc. Mention may be made of nitrogen, nitrogen compounds such as nitrides and azides. In addition to this, in addition to introducing nitrogen atoms (N), halogen atoms (X) can also be introduced, so nitrogen trifluoride (F ₃ N), nitrogen tetrafluoride (F ₄ N ₂ ), etc. Mention may be made of halogenated nitrogen compounds. In the present invention, the layer region (N) may further contain oxygen atoms in addition to nitrogen atoms in order to further enhance the effect obtained by nitrogen atoms. Examples of raw material gases for introducing oxygen atoms into the layer region (N) include oxygen (O ₂ ), ozone (O ₃ ), nitrogen monoxide (NO), nitrogen dioxide (NO ₂ ), Nitrogen monoxide (N ₂ O), nitrogen sesquioxide (N ₂ O ₃ ), trinitrogen tetraoxide (N ₂ O ₄ ), nitrogen pentoxide (N ₂ O ₅ ), nitrogen trioxide (NO ₃ ), silicon atoms (Si), oxygen atom (O), and hydrogen atom (H) as constituent atoms, such as lower siloxanes such as disiloxane (H ₃ SiOSiH ₃ ) and trisiloxane (H ₃ SiOSiH ₂ OSiH ₃ ). I can do it. To form the layer region (N) containing nitrogen atoms by the sputtering method, a monocrystalline or polycrystalline Si wafer or a Si ₃ N ₄ wafer, or a Si
This can be carried out by targeting a wafer containing a mixture of Si 3 N 4 and Si ₃ N ₄ and sputtering them in various gas atmospheres. For example, if a Si wafer is used as a target, nitrogen atoms and optionally hydrogen atoms or/and
The raw material gas for introducing halogen atoms is diluted with a diluting 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. Good. Alternatively, by using Si and Si ₃ N ₄ as separate targets, or by using a mixed target of Si and Si ₃ N ₄ , a dilution gas atmosphere can be created as a sputtering gas. The sputtering is performed in a gas atmosphere containing at least hydrogen atoms (H) and/or halogen atoms (X) as constituent atoms. As the raw material gas for introducing nitrogen atoms, the raw material gas for introducing nitrogen 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. In the present invention, when a layer region (N) containing nitrogen atoms is provided when forming a photoreceptive layer, the distribution concentration C of nitrogen atoms contained in the layer region (N) is
Layer region (N) having a desired distribution state (depth profile) in the layer thickness direction by changing (N) in the layer thickness direction
To form the starting material gas for introducing nitrogen atoms, whose distribution concentration C(N) should be changed in the case of a glow discharge, the gas flow rate thereof is appropriately changed according to a desired rate of change curve. This is accomplished by introducing the liquid into the deposition chamber. For example, the opening of a predetermined needle valve provided in the middle of the gas passage system may be gradually changed by some commonly used means such as manually or by 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 rate-of-change curve designed in advance to obtain a desired content rate curve. When the layer region (N) is formed by sputtering, the distribution concentration of nitrogen atoms in the layer thickness direction C(N)
In order to form a desired depth profile of nitrogen atoms in the layer thickness direction by changing the depth profile in the layer thickness direction, first, as in the case of the glow discharge method, the starting point for introducing nitrogen atoms is This is accomplished by using the substance in a gaseous state and varying the gas flow rate at which the gas is introduced into the deposition as desired. Second, the target for sputtering,
For example, if a mixed target of Si and Si ₃ N ₄ is used, the mixing ratio of Si and Si ₃ N ₄ should be
This is accomplished by changing the layer thickness of the target in advance. In the present invention, hydrogen atoms (H) contained in the second layer region (S) constituting the photoreceptive layer to be formed
The amount of halogen atoms (X) or the sum of the amounts of hydrogen atoms and halogen atoms (H+X) is preferably 1 to 40 atomic %, more preferably 5 to 40 atomic %.
It is desirable that it be 30 atomic %, most preferably 5 to 25 atomic %. 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, 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 any shape such as a cylinder, a belt, or a plate, 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 the desired photoconductive member is formed, but when 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, from the viewpoint of manufacturing and handling of the support, mechanical strength, etc., the thickness is usually set to 10μ or more. Next, an outline of an example of a method for manufacturing a photoconductive member for electrophotography according to 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 the photoconductive member of the present invention is sealed, for example, 110
2 is SiH ₄ gas diluted with He (99.999% purity,
Hereinafter, it will be abbreviated as SiH ₄ /He. ) cylinder, 1103 is He
_GeH4 gas diluted with (purity 99.999% or less)
Abbreviated as GeH ₄ /He. ) cylinder, 1104 is SiF ₄ gas diluted with He (99.99% purity, hereinafter referred to as SiF ₄ /He)
It is abbreviated as ) cylinder, 1105 is NH ₃ gas (purity
99.999%) cylinder, 1106 is _H2 gas (purity
99.999%) cylinder. In order to flow these gases into the reaction chamber 1101, valves 112 of gas cylinders 1102 to 1106 are used.
2-1126, confirm that the leak valve 1135 is closed, and also check that the inflow valve 1112-1126 is closed.
Step 1116: After confirming that the outflow valves 1117 to 1121 and the auxiliary valves 1132 and 1133 are open, first open the main valve 1134 to exhaust the reaction chamber 1101 and each gas pipe. Next, when the reading on the vacuum gauge 1136 reaches approximately 5×10 ^-6 torr, the auxiliary valves 1132 and 1133 and the outflow valves 1117 to 1121 are closed. Next, to give an example of forming a light-receiving layer on the cylindrical substrate 1137, the gas cylinder 11
SiH ₄ /He gas from 02, GeH ₄ /He gas from gas cylinder 1103, gas from gas cylinder 1105
NH ₃ gas valves 1122, 1123, 112
5 and outlet pressure gauges 1127, 1128, 1
Adjust the pressure of 130 to 1Kg/cm ² and open the inflow valve 11.
12, 1113, 1115 gradually, and mass flow controllers 1107, 1108, 1110
Let them flow into each other. Subsequently, the outflow valve 11
17, 1118, 1120, auxiliary valve 1132
are gradually opened to allow each gas to flow into the reaction chamber 1101. At this time, the SiH ₄ /He gas flow rate and
The outflow valves 1117 and 111 are adjusted so that the ratio between the GeH ₄ /He gas flow rate and the NH ₃ gas flow rate becomes a desired value.
8 and 1120, and also adjust the opening of the main valve 1134 while checking the reading on the vacuum gauge 1136 so that the pressure inside the reaction chamber 1101 reaches the desired value. After confirming that the temperature of the substrate 1137 is set to a temperature in the range of approximately 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. A glow discharge is maintained for a desired time to form a first layer region (G) on the substrate 1137 to a desired layer thickness. At the stage where the first layer region (G) has been formed to the desired layer thickness, the same conditions and procedures are followed except for completely closing the outflow valve 1118 and changing the discharge conditions as necessary. By maintaining the glow discharge for a desired time, a second layer region (S) substantially free of germanium atoms can be formed on the first layer region (G). In order to contain a substance that controls conductivity in the second layer region (S), a gas such as B ₂ H ₆ or PH ₃ is introduced into the deposition chamber 110 during the formation of the second layer region (S).
All you have to do is add it to the gas introduced into 1. During layer formation, the substrate 1137 is preferably rotated at a constant speed by a motor 1139 in order to ensure uniform layer formation. Examples will be described below. Example 1 Using the manufacturing apparatus shown in FIG. 11, layers were formed on a cylindrical Al substrate under the conditions shown in Table 1 to obtain an electrophotographic image forming member. The image forming member thus obtained was placed in a charging exposure experimental device, corona charged at 5.0 kV for 0.3 seconds, and immediately irradiated with a light image. The optical image was generated using a tungsten lamp light source, and a light intensity of 2 lux·sec was irradiated through a transmission type test chart. Immediately thereafter, a good toner image was obtained on the imaging member surface by cascading a chargeable developer (including toner and carrier) onto the imaging member surface. the toner image on the imaging member;
Transferred onto transfer paper with 5.0kV corona charging,
Clear, high-density images with excellent resolution and good gradation reproducibility were obtained. Example 2 Using the manufacturing apparatus shown in FIG. 11, layers were formed in the same manner as in Example 1 except that the conditions shown in Table 2 were used to obtain an electrophotographic image forming member. 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, except that the charge polarity and the charge polarity of the developer were opposite to those in Example 1. The image was extremely clear. A good image quality was obtained. Example 3 Layer formation was carried out in the same manner as in Example 1 except that the conditions shown in Table 3 were changed using the manufacturing apparatus shown in FIG. 11 to obtain an electrophotographic image forming member. When an image was formed on a transfer paper using the image forming member thus obtained under the same conditions and procedures as in Example 1, an extremely clear image quality was obtained. Example 4 In Example 1, GeH ₄ /He gas and SiH ₄ /
An electrophotographic image forming member was obtained in the same manner as in Example 1, except that the content of germanium atoms contained in the first layer was changed as shown in Table 4 by changing the gas flow rate ratio of He gas. Ta. 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 the results shown in Table 4 were obtained. Example 5 Electrophotographic image forming members were prepared in the same manner as in Example 1 except that the thickness of the first layer was changed as shown in Table 5. For each image forming member thus obtained, an image was formed on a transfer paper under the same conditions and procedures as in Example 1, and the results shown in Table 5 were obtained. Example 6 Using the manufacturing apparatus shown in FIG. 11, layers were formed on a cylindrical Al substrate under the conditions shown in Table 6 to obtain an electrophotographic image forming member. The image-forming member thus obtained was installed in a charging exposure experimental device, corona charged at 5.0 kV for 0.3 seconds, and a light image was immediately irradiated using a tungsten lamp light source to transmit a light amount of 2 lux sec to a transmission type. It was irradiated through a test chart. Immediately thereafter, a good toner image was obtained on the imaging member surface by cascading a chargeable developer (including toner and carrier) onto the imaging member surface. the toner image on the imaging member;
Transferred onto transfer paper with 5.0kV corona charging,
Clear, high-density images with excellent resolution and good gradation reproducibility were obtained. Example 7 In Example 1, the light source was an 810 nm GaAs semiconductor laser (10 mW) instead of the tungsten lamp.
Example 1 was carried out under the same toner image forming conditions as in Example 1, except that an electrostatic image was formed using
When the image quality of the toner-transferred image was evaluated using an electrophotographic image forming member prepared under the same conditions as described above, a clear, high-quality image with excellent resolution and good gradation reproducibility was obtained.

【table】

【table】

【table】

[Table] ◎: Excellent ○: Good △: Adequate for practical use

[Table] ◎: Excellent ○: Good

[Table] Common layer forming conditions in the above embodiments of the present invention are shown below. Substrate temperature: germanium atom (Ge) containing layer
...About 200℃ No germanium atom (Ge) content
...Approx. 250℃ Discharge frequency: 13.56MHz Reaction chamber pressure during reaction: 0.3Torr

[Brief explanation of drawings]

FIG. 1 is a schematic layer structure diagram for explaining the layer structure of the electrophotographic photoconductive member of the present invention, and FIGS. 2 to 10 each show the distribution state of nitrogen atoms in the layer region (N). FIG. 11, which is an explanatory diagram for explaining the present invention, is a schematic explanatory diagram of an apparatus used for producing the electrophotographic photoconductive member of the present invention in Examples. 100...Photoconductive member, 101...Support, 1
02...Photoreceptive layer, 103...First layer region (G),
104...Second layer region (S).

Claims (1)

[Scope of Claims] 1. A support for a photoconductive member for electrophotography, and an amorphous material containing germanium atoms in an amount of 1 to 10×10 ⁵ atomic ppm based on the sum of silicon atoms on the support. A first layer region (G) with a layer thickness of 30 Å to 50 μm consisting of a layer having a thickness of 0.5 to 90 μm consisting of an amorphous material containing silicon atoms (but not containing germanium atoms)
A photoconductive member for electrophotography, wherein the second layer region (S) comprises a photoreceptive layer exhibiting photoconductivity and having a layer thickness of 1 to 100 μm and provided in order from the support side, The number of nitrogen atoms in the photoreceptive layer is 0.001~
A photoconductive member for electrophotography, characterized in that it contains 50 atomic %. 2. The photoconductive member for electrophotography according to claim 1, wherein at least one of the first layer region (G) and the second layer region (S) contains hydrogen atoms. 3. The electrophotography according to claim 1 or 2, wherein at least one of the first layer region (G) and the second layer region (S) contains a halogen atom. Photoconductive materials for use.