JPS6161103B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to light (light in a broad sense here, ultraviolet rays,
The present invention relates to an electrophotographic imaging member used to form an image using electromagnetic waves such as visible light, infrared light, X-rays, gamma rays, etc.

[Conventional technology]

Conventionally, photoconductive materials constituting the photoconductive layer of electrophotographic image forming members include inorganic photoconductive materials such as Se, CdS, and ZnO, poly-N vinyl carbazole (PVK), and trinitrofluorenone (TNF). Organic photoconductive materials (OPC) are commonly used.

However, in electrophotographic image forming members using these photoconductive materials, there are still various issues that can be resolved, and the conditions may be relaxed to a certain extent to suit individual circumstances. In reality, each suitable electrophotographic imaging member is used.

For example, in an electrophotographic image forming member that uses Se as a photoconductive layer forming material, Se alone has a narrow spectral sensitivity range when using visible light, so Te or As is added to improve the spectral sensitivity. Plans are being made to expand the area.

However, although electrophotographic image forming members having such Se-based photoconductive layers containing Te and As certainly improve the spectral sensitivity range, optical fatigue increases, making it difficult to print the same original. Continuous and repeated copying may cause a decrease in the line density of the copied image and background stains (so-called fog due to stains on the white background).
Furthermore, when another document is subsequently copied, the image of the previous document is copied as an afterimage (ghost development).

However, since Se, especially As and Te, are extremely harmful substances to the human body, it is necessary to devise ways to use manufacturing equipment that does not come into contact with the human body during manufacturing. The capital investment is significantly large. Furthermore, if the photoconductive layer is exposed even after manufacturing, the surface of the photoconductive layer will be directly rubbed during cleaning and other treatments, and a portion of it will be scraped off, causing the developer to They may get mixed into the machine, be scattered inside the copying machine, or be mixed into the copied images, causing them to come into contact with the human body.

Furthermore, when the surface of a Se-based photoconductive layer is continuously and repeatedly exposed to corona discharge many times, crystallization or oxidation occurs near the surface of the layer, leading to deterioration of the electrical properties of the photoconductive layer. There are many cases. Or again,
If the surface of the photoconductive layer is exposed, when a liquid developer is used to visualize (develop) the electrostatic latent image,
Since it comes into contact with the solvent, it is required to have excellent solvent resistance (resistance to liquid development), but in this regard, it cannot be said that the Se-based photoconductive layer necessarily satisfies the conditions. hard.

Separately, Se-based photoconductive layers are usually formed by vacuum evaporation, which requires significant capital investment in equipment and is difficult to reproduce a photoconductive layer with desired photoconductive properties. In order to obtain good performance, it is necessary to strictly adjust various manufacturing parameters such as evaporation temperature, evaporation substrate temperature, degree of vacuum, evaporation rate, and cooling rate.

In addition, the Se-based photoconductive layer is formed in an amorphous state in order to have high dark resistance as a photoconductive layer of an electrophotographic image forming member, but Se crystallization occurs at an extremely low temperature of approximately 65°C. Therefore, crystallization development occurs due to the influence of the ambient temperature during handling after manufacture or during use, and the frictional heat caused by rubbing against other members during the image forming process. It also has a drawback in terms of heat resistance, which tends to cause a decrease in dark resistance.

On the other hand, electrophotographic imaging members that use ZnO, CdS, etc. as photoconductive layer constituent materials have a photoconductive layer in which particles of the photoconductive material such as ZnO or CdS are uniformly dispersed in a suitable resin binder. It is formed by This electrophotographic image forming member having a so-called binder-based photoconductive layer is advantageous in manufacturing compared to an electrophotographic image forming member having an Se-based photoconductive layer, and has a relatively low manufacturing cost. can be measured. That is, the binder-based photoconductive layer is made of ZnO or CdS.
A coating solution prepared by kneading particles of and a suitable resin binder using a suitable solvent is applied onto a suitable substrate.
Since it can be formed by simply applying it using a coating method such as the doctor blade method or dipping method and then solidifying it, it does not require a significant investment in manufacturing equipment compared to electrophotographic image forming members that have a Se-based photoconductive layer. Not only is there no problem, but the manufacturing method itself is simple and easy.

However, the binder-based photoconductive layer is basically a two-component system consisting of a photoconductive material and a resin binder, and the photoconductive material particles are uniformly dispersed in the resin binder. Due to the specific characteristics of the photoconductive layer, there are many parameters that determine the electrical and photoconductive properties as well as the physical and chemical properties of the photoconductive layer. It is not possible to form a conductive layer with good reproducibility,
This method has the disadvantage that it leads to a decrease in yield and lacks mass productivity.

In addition, because the binder-based photoconductive layer is a dispersed system, the entire layer is porous, and as a result, it is highly dependent on humidity, and when used in a humid atmosphere, the electrical properties deteriorate, making it difficult to maintain high quality. In many cases, it becomes impossible to obtain a duplicate image.

Furthermore, the porous nature of the photoconductive layer causes developer to enter the layer during development, which not only reduces mold releasability and cleaning properties but also makes it unusable. When a developer is used, the developer permeates into the layer together with the carrier solvent due to capillary action, which makes the above point more significant, so it is necessary to cover the surface of the photoconductive layer with a surface coating layer. .

However, even with this improvement by providing a surface coating layer, the surface of the photoconductive layer is uneven due to the porous nature of the photoconductive layer, so the interface is not uniform and the adhesion between the photoconductive layer and the surface coating layer is poor. Another disadvantage is that it is difficult to obtain good electrical contact.

In addition, when using CdS, since CdS itself has an effect on the human body, care must be taken during manufacturing and use to prevent it from coming into contact with the human body or scattering into the surrounding environment. There is a need to.

When using ZnO, there is almost no effect on the human body, but ZnO binder-based photoconductive layers have low photosensitivity, narrow spectral range, and significant optical fatigue.
It has drawbacks such as slow photoresponsiveness.

In addition, in electrophotographic image forming members using organic photoconductive materials such as PVK and TNF, which have recently been attracting attention, PVK, TNF, etc. This method has the advantage in manufacturing that a photoconductive layer can be formed simply by forming a coating film of an organic photoconductive material, and the advantage that an electrophotographic image forming member with excellent flexibility can be manufactured. On the other hand, it has the drawback of low photosensitivity, for example, when the light used for image formation is in the visible light range, the spectral sensitivity range is narrow and biased toward the short wavelength side, and the range is extremely limited. It is only used for this purpose.

As described above, electrophotographic image forming members using photoconductive materials, which have been pointed out as photoconductive layer forming materials for electrophotographic image forming members, have both advantages and disadvantages, so they are subject to certain manufacturing conditions and In order to meet the usage conditions, the current situation is to relax the manufacturing and usage conditions to some extent and to select an appropriate electrophotographic image forming member suitable for each use and put it into practical use.

Therefore, there is a need for a third material for forming the photoconductive layer of an electrophotographic image forming member, which can provide an excellent electrophotographic image forming member that solves the above-mentioned problems.

Among such materials that have recently been viewed as promising is amorphous silicon (hereinafter abbreviated as A-Si).

In the early stages of development, A-Si films exhibited various electrical and optical properties due to their structure being influenced by the manufacturing method and manufacturing conditions, which caused major problems in terms of reproducibility. I was holding it. For example, in the early stages, A-Si films formed by vacuum evaporation or sputtering methods contained a large number of defects such as voids, which greatly affected their electrical and optical properties. As a result, it did not receive much attention as a research material for fundamental physical properties, and no research and development efforts were conducted for its application. However, it was thought that p and n control was impossible in amorphous, but in A-Si,
In early 1976, the first amorphous p-n
Report that bonding can be realized (Applied Physics
Letter; Vol 28, No. 2, 15 January 1976), there has been a great deal of interest, and since then, in addition to the fact that p-n junctions can be obtained by doping the impurities mentioned above, crystalline silicon (C- Since luminescence, which is very weak in A-Si (abbreviated as "Si"), can be observed with high efficiency, research and development efforts have been focused mainly on its application to solar cells.

In this way, the A-Si films that have been reported so far have been developed for solar power applications, so in terms of their electrical and optical properties,
The reality is that it cannot be used as a photoconductive layer in an electrophotographic imaging member. In other words, solar cells convert solar energy into electric current and extract it.
In order to not only have a good signal-to-noise ratio but also to extract a large current efficiently, the resistance of the A-Si film must be low to some extent, but if the resistance is too small, the photosensitivity will decrease and the signal-to-noise ratio will deteriorate. As one of its characteristics, a resistance of about 10 ⁵ to 10 ⁸ Ω·cm is required. However, the resistance (dark resistance) of the A-Si film having this level of resistance (dark resistance) is too low to be used as a photoconductive layer of an electrophotographic image forming member. As it is, it cannot be used at all by applying currently known electrophotographic methods.

Furthermore, as a photoconductive layer forming material for electrophotographic image forming members, bright resistance (resistance when irradiated with light) is required to be about 2 to 4 orders of magnitude smaller than dark resistance.
Conventionally reported A-Si films have a photoconductive layer of about two digits at most, and even in this respect, conventional A-Si films could not provide a photoconductive layer that fully satisfies these characteristics.

In addition, according to a separate report regarding A-Si films, for example, A-Si films with a dark resistance of 10 ¹⁰ Ωcm have a decreased photoelectric gain (photocurrent per incident photon); However, the conventional A-Si film could not be used as a perfect photoconductive layer for an electrophotographic image forming member.

[Purpose and structure]

The present invention has been made in view of the above points, and
-As a result of intensive research and study on Si from the perspective of applying it to electrophotographic image forming members, we have found that an A-Si layer with a layer structure having certain characteristics and an organic compound layer as detailed below. If these are laminated, the resulting electrophotographic image forming member is not only usable for practical use, but also surpasses conventional electrophotographic image forming members in most respects. It is based on the point that was found.

The present invention makes it possible to easily create a closed system for manufacturing equipment during manufacturing, thereby avoiding adverse effects on the human body. Furthermore, it is non-polluting and has no effect on the natural environment, has excellent moisture resistance, always stable electrophotographic properties, is suitable for all environments with almost no restrictions on usage environments, and is resistant to light fatigue. The main object of the present invention is to provide an electrophotographic imaging member that is extremely long and does not deteriorate even after repeated use.

Another object of the present invention is to provide an electrophotographic image forming member that can easily produce high-quality images with high density, clear halftones, and high resolution.

Another object of the present invention is to provide an electrophotographic image forming member that has high photosensitivity, has a spectral sensitivity range that covers almost the entire visible light range, has a low dark decay rate, and has fast photoresponsiveness. It is to be.

Still another object of the present invention is to provide an electrophotographic image forming member with less restrictions on the time required for development after electrostatic image formation and the time required for development.

The intended purpose of the present invention is to generate a mobile carrier having a depletion layer and by electromagnetic wave excitation,
an amorphous silicon layer containing 1 to 40 atomic percent of hydrogen, into which carriers generated in the layer are implanted, and for transporting the injected carriers;
This is achieved by an electrophotographic image forming member characterized in that a layer made of an organic compound is laminated.

The most typical structural example of the electrophotographic image forming member of the present invention is shown in FIGS. 1 and 2.

The electrophotographic imaging member 1 shown in FIG.
It is composed of a support 2 for an image forming member applied to electrophotography, an A-Si layer 3 containing 1 to 40 atomic % of hydrogen, and a layer 4 made of an organic compound. A depletion layer 6 is formed in the layer 3 , and the layer 4 has a free surface 5 .

The depletion layer 6 formed in the A-Si layer in the present invention is formed by the electromagnetic waves irradiated during the electromagnetic wave irradiation step, which is one step in the process of forming an electrostatic image on the image forming member 1. It functions as a layer that generates a movable carrier when acted upon.

In the present invention, since the A-Si layer 3 has the depletion layer 6 having the above-mentioned function, depending on the direction in which the image forming member 1 is irradiated with electromagnetic waves, the The support 2 is designed so that sufficient carriers can be generated in the depletion layer 6 to form an electrostatic image with sufficient contrast, that is, so that the electromagnetic waves can sufficiently reach the depletion layer 6. It is necessary to form one of layer 4 and layer 4.

That is, for example, in the case of irradiating electromagnetic waves from the layer 4 side in FIG. It is necessary to select the material and determine the layer thickness so that it can reach the layer 6. Conversely, when irradiating electromagnetic waves from the support 2 side, if the support 2 is under the above conditions. It is necessary to select the material and determine the layer thickness as in the case of layer 4.

Further, in the image forming member 1 shown in FIG. 1, an A-Si based layer 3 is formed on the support 2, and
Although the layer 4 is formed on the -Si-based layer 3, the order of the layer structure does not necessarily limit the present invention. A layer structure order having a free surface may also be used. With this layer configuration, when electromagnetic waves are irradiated from the A-Si layer 3 side, the organic compound layer 4 and the support 2 generate sufficient carrier in the depletion layer 6 as described above. It is not necessary to allow a large amount of electromagnetic waves to reach the depletion layer 6. On the other hand, when electromagnetic waves are irradiated from the support 2 side, the support 2 and layer 4 are exposed to an amount of electromagnetic waves that generates sufficient carrier in the depletion layer 6, as described above. It is necessary to select the material and determine the layer thickness so that the depletion layer 6 can reach the depletion layer 6.

In the present invention, in order to provide the depletion layer 6 in the A-Si layer 3, at least two types of A-Si of the following types are selected for the layer 3, and the different types are bonded. This is accomplished by forming layers in a state where the

n-type A-Si: contains only a donor, or contains both a donor and an acceptor, and has a high donor concentration (Nd).

Among the n ⁺ type A-Si...types, those with particularly strong n-type characteristics (higher Nd).

p-type A-Si...Contains only an acceptor. Or one that contains both a donor and an acceptor and has a high acceptor concentration (Na).

Among the p ⁺ type A-Si...types, those with particularly strong p-type characteristics (higher Na content).

i-type A-Si...NaNdO or Na
Nd's.

That is, the depletion layer 6 is formed, for example, by first depositing i-type A-Si on the support 2 having desired surface characteristics.
The i-type A-Si layer and the p-type A-Si layer are bonded by forming a layer with a predetermined thickness and then forming a p-type A-Si layer on the i-type A-Si layer. (hereinafter, A- on the support body 2 side with respect to the depletion layer 6)
The Si layer is referred to as an inner layer, and the A-Si layer on the free surface 5 side is referred to as an outer layer). A plugging and depletion layer 6 is formed in the boundary transition region between the inner A-Si layer and the outer A-Si layer when the layer 3 is formed such that different types of A-Si layers are joined.

In a steady state, the depletion layer 6 in the present invention is depleted of free carriers, so it behaves as a so-called intrinsic semiconductor.

In the present invention, the inner layer 7 and the outer layer 8, which are the layers constituting the A-Si layer 3, are made of the same type of material, A-Si, and their junction (depletion layer 6) is homogeneous. (homo) bonding, the inner layer 7 and the outer layer 8 are electrically and optically well bonded, and the energy bands of the inner layer and the outer layer are smoothly bonded. There is. Further, in the depletion layer 6, there is a unique electric field (diffusion potential) (inclination of energy band) that is formed when the layer 6 is formed. For this reason, not only the carrier generation efficiency is improved, but also the recombination probability of the generated carriers is reduced, that is, the quantum probability is increased, the photoresponse is accelerated, and the generation of residual charges is prevented. arise.

Therefore, the present invention has the advantage that carriers generated in the depletion layer 6 by irradiation with electromagnetic waves such as light work effectively by forming an electrostatic image.

Further, in order to utilize the features of the image forming member of the present invention more effectively, the image forming member of the present invention has an A-
The free surface is charged by selecting the charging polarity so that a reverse bias voltage is applied to the depletion layer 6 formed in the Si-based layer 3. When this reverse bias is applied to the depletion layer 6, the thickness of the depletion layer 6 increases by approximately the 1/2 power of the voltage applied to the layer 6. for example,
Under high voltage (10 ⁴ V/cm or more), the thickness of the depletion layer 6 becomes several to several tens of times as large as the thickness when no charging treatment is performed. Furthermore, application of a reverse bias to the depletion layer 6 makes the inherent electric field (diffusion potential) formed by the junction even steeper.

This makes the effect mentioned above even more remarkable.

In the present invention, as described above, the inner layer 7 and the outer layer 8 are formed of the same kind of material, and the depletion layer 6
Since it is formed by bonding the inner layer 7 and the outer layer 8, it also has the advantage that the entire A-Si layer 3 can be formed in a continuous manufacturing process.

The thickness of the depletion layer 6 is as follows:
and the dielectric constant of the outer layer 8 and the difference in the Fermi level before bonding between the two layers, that is, the density of impurities doped into the layer to control the bonded A-Si layer to the above-mentioned type. It can be varied from several angstroms to several microns by particularly adjusting the doping amount of impurities.

As described above, the thickness of the depletion layer 6 increases due to reverse bias, so when used with reverse bias, the thickness can be expanded to several hundreds of angstroms to several tens of microns. Therefore, the thickness of the depletion layer 6 can be changed appropriately depending on the degree of reverse bias.

However, when applying a high electric field reverse bias onto the depletion layer 6, it is necessary to determine the impurity concentration and applied voltage, which will be described later, to an extent that does not cause tunneling or avalanche breakdown. In other words, if the impurity concentration is too high, tunneling or avalanche breakdown will occur with a relatively low reverse bias, resulting in sufficient expansion of the depletion layer 5 (reduction in electric capacity) and sufficient electric field to the depletion layer 6. becomes impossible.

In the present invention, since the depletion layer 6 has the role of absorbing electromagnetic waves and generating carriers, it is necessary to absorb as much electromagnetic waves as possible entering the depletion layer 6. It is better to make the layer thicker.
On the other hand, the strength per unit thickness of the inherent electric field formed in the depletion layer 6, which is an important factor for reducing the recombination rate of carriers generated in the depletion layer 6, is , is inversely proportional to the layer thickness, so
In this respect, the thinner the depletion layer 6 is, the better.

Therefore, in the present invention, the above two points need to be taken into consideration in order to fully achieve the object. That is, in the present invention, carriers are mostly generated in the depletion layer 6 by electromagnetic wave irradiation, so
According to the irradiation direction when irradiating the image forming member 1 with electromagnetic waves, sufficient carrier is applied to the depletion layer 6 to form an electrostatic image with sufficient contrast on either the inner layer 7 or the outer layer 8. The depletion layer 6 needs to be formed in such a way that the electromagnetic waves can be generated therein, that is, the irradiated electromagnetic waves can sufficiently reach the depletion layer 6. By the way, visible light is employed as the electromagnetic wave to be irradiated in an electrophotographic image forming member that is used for normal use. Therefore, since the optical absorption coefficient of A-Si is 5×10 ⁵ to 10 ⁴ cm ^-1 in the wavelength range of 400 to 700 mm, in order to achieve the above objective, at least when the charging treatment is performed, , either the inner layer 7 or the outer layer 8 is used as the layer on the light irradiation side so that at least a part of the depletion layer 6 exists within 5000 Å from the layer surface on the light irradiation side in the A-Si layer. need to be formed. In addition, as for the lower limit of the layer thickness, it is basically sufficient that the depletion layer 6 is formed by joining the inner layer 7 and the outer layer 8, so the thinner the layer, the better the electromagnetic wave irradiation amount. Since the carrier generation efficiency in the depletion layer 6 can be increased, the thickness is made as thin as possible based on manufacturing technology.

By the way, the dark resistance of the A-Si layer, which is considered to be p-type (including p ⁺ type) or n-type (including n ⁺ type), changes greatly depending on the impurity concentration, and most of this changes from the conventional electrophotographic point of view. Therefore, the dark resistance is too low to be used at all.

The reason for this is that if the resistance is too low, there is not enough surface resistance to prevent the charge from escaping in the lateral direction when an electrostatic image is formed, so a highly sensitive latent image cannot be created, and the thermal excitation free This is because no electrostatic latent image is formed because there is no difference between the carrier and the photoexcited free carrier.

However, in the present invention, even in an electrophotographic image forming member in which the A-Si layer is formed as a layer having a free surface, the depletion layer 6 can be removed by applying the reverse bias to the depletion layer 6 described above. There is an expansion in the layer thickness, and this fact means that free carriers are swept away.
This means that even though the external layer has a relatively low resistance, it appears to have a high resistance, and charging in the reverse bias direction has the effect of sweeping free carriers in the external layer toward the surface. Therefore, the expansion effect of the depletion layer and the effect of sweeping away the free carriers described above, which constitute the outer layer, are sufficient to achieve the object of the present invention. This makes it possible to use even those having a relatively low resistance value, which were considered unusable from the conventional electrophotographic viewpoint, if expected.

Either one of the inner layer 7 and the outer layer 8,
A layer other than the layer on the electromagnetic wave irradiation side, in other words, a layer on the opposite side of the electromagnetic wave irradiation side with respect to the depletion layer 6 has a function of effectively transporting the charges generated in the depletion layer 6, and also serves as an A-Si layer. It can also be formed so as to greatly contribute to the magnitude of the capacitance.

For this reason, such a layer usually has a thickness of 0.1 to 10 μm, preferably 0.1 μm, taking into account economic considerations including manufacturing cost and manufacturing time of the image forming member to be manufactured.
It is desired that the layer thickness be formed in the range of ~7 μm.

In FIG. 1, for a preferred embodiment of the imaging member of the present invention, two different types of A from among the types are shown as the inner layer 7 and the outer layer 8.
-Select Si layer, e.g. p type and i type, p ⁺ type and i
We will give an example of selecting a combination of type, n ⁺ type and i type, p type and n type, etc. and bonding these to form an A-Si layer 3, and explain its superiority over the conventional method. As explained above, furthermore, from the support body 2 side, p.
A good embodiment of the present invention can also be achieved by forming an A-Si layer by bonding three different types of A-Si layers, such as i.n. and n.i.p. In this case, two depletion layers will exist in the photoconductive layer.

In this case, since a high electric field can be applied by dividing into two depletion chambers, a large electric field can be applied, and it becomes easier to obtain a high surface potential.

When the A-Si layer has a layer structure of n.i.p or p.i.n from the support side, it has the following characteristics and various electrophotographic processes can be applied. You will get it.

In other words, it has the effect of preventing charge injection into the A-Si layer from the support side, and furthermore, it is possible to irradiate electromagnetic waves from both the surface side and the support side, so both sides can be irradiated with the same image or different images. Simultaneous add by irradiation
It also enables on-type image irradiation. Furthermore, it is also possible to use backside irradiation (irradiation from the support side) to erase electrostatic images, or backside irradiation using the NP method (to promote charge injection from the support side), which will be described later, to improve durability. becomes.

As the layer constituting the A-Si layer of the electrophotographic image forming member of the present invention, the A-Si layer of the type ~ is as follows:
As will be detailed later, during layer formation by glow discharge method, reactive sputtering method, etc., n-type impurities (to make the formed A-Si layer or type) or p-type impurities (to make the formed A-Si layer (type of Si layer) or by doping both impurities into the A-Si layer to be formed by controlling their amounts.

In this case, according to the findings from the experimental results of the present inventors, by adjusting the impurity concentration in the layer within the range of 10 ¹⁵ to 10 ¹⁹ cm ^-3 , stronger n-type (or stronger strong p-type) A-Si layer to weaker n-type
type (or weaker p-type) A-Si layer can be formed.

A-Si layer of type ~ is prepared by glow discharge method,
It is formed by a sputtering method, an ion implantation method, an ion plating method, or the like. These manufacturing methods are selected and adopted as appropriate depending on factors such as manufacturing conditions, level of equipment capital investment, manufacturing scale, and electrophotographic characteristics desired for the image forming part to be manufactured. A-Si is relatively easy to control to produce an imaging member with electrophotographic properties.
In order to introduce impurities into the layer, the glow discharge method is preferably employed because of its advantages such as being able to introduce group or group impurities in a substitutional manner.

Furthermore, in the present invention, the glow discharge method and the sputtering method are used together in the same system to produce A-Si.
A layer may be formed. The dark resistance and photoelectric gain of the A-Si layer can be controlled by containing hydrogen (H), for example, so that the electrophotographic image forming member targeted by the present invention can be obtained. Here, “A-Si
"H is contained in the layer" means "H
is combined with Si,""H is ionized and incorporated into the layer," or "H is incorporated into the layer as H ₂ ," or a combination of these. means state. The inclusion of H in the A-Si layer is due to the presence of hydrogen in the manufacturing equipment system when forming the layer.
After introducing compounds such as SiH ₄ and Si ₂ H ₆ or in the form of H ₂ , by methods such as thermal decomposition and glow discharge decomposition,
These compounds or H ₂ may be decomposed and incorporated into the A-Si layer as the layer grows, or
It may be contained by ion implantation method.

According to the knowledge of the present invention, the content of H in the A-Si layer is one of the major factors that influences whether or not the formed image forming member can be applied in practice. In particular, the formed A-Si layer is p-type or n-type.
It has been found to be extremely important as an element in controlling the type.

In the present invention, the amount of H contained in the A-Si layer is usually 1 to 40 atomic %, preferably 1 to 40 atomic %, in order to make the image forming member formed sufficiently suitable for practical use. is preferably set to 5 to 30 atomic%. The theoretical basis for why the H content in the A-Si layer is limited to the above-mentioned numerical range has not yet been clarified and remains in the realm of speculation. However, from a number of experimental results, it has been found that H content outside the above numerical range does not provide the characteristics required for the inner layer or outer layer constituting the A-Si layer of the image forming member of the present invention, for example. Manufactured electrophotographic imaging members have very low sensitivity to irradiated electromagnetic radiation, which is extremely difficult to control, or in some cases
It was observed that the sensitivity was hardly observed, the increase in carrier due to electromagnetic wave irradiation was small, etc., and it was confirmed that it is a necessary condition that the H content is within the above numerical range. For example, in the glow discharge method, the inclusion of H in the A-Si layer depends on the production conditions described below, since hydrides such as SiH ₄ and Si ₂ H ₆ are used as the starting material for forming A-Si. _SiH4 ,
When a hydride such as Si ₂ H ₆ is decomposed to form an A-Si layer, H is automatically contained in the layer, but in order to more efficiently incorporate H into the layer, ,A
- When forming the Si layer, H ₂ gas may be introduced into the apparatus system that performs glow discharge.

When using the sputtering method, H ₂ gas is introduced when sputtering is performed using Si as a target in an atmosphere of an inert gas such as Ar or a mixed gas based on these gases, or
A silicon hydride gas such as SiH ₄ or Si ₂ H ₆ or a gas such as B ₂ H ₆ or PH ₃ which also serves as impurity doping may be introduced.

In order to control the amount of H contained in the A-Si layer in order to achieve the object of the present invention, the substrate temperature or/and the introduction of the starting material used to contain H into the production equipment system. All you have to do is control the amount, etc. Furthermore, one method is to heat the A-Si layer at a temperature below the crystallization temperature after forming the A-Si layer. Especially A
- This heat treatment method is an effective means for improving the dark resistance of the Si layer. Another effective method is to improve the dark resistance of the A-Si layer by irradiating it with electromagnetic waves such as high-intensity light.

In order to make the A-Si layer p-type, suitable impurities to be doped into the A-Si layer include elements from group A of the periodic table, such as B, Al, Ga, In, and Tl. In the case of n-type, elements of group A of the periodic table, such as N, P, As,
Preferred examples include Sb and Bi. These impurities are contained in the A-Si layer in an amount of ppm
Since the photoconductive layer is of the order of magnitude, it is not necessary to pay as much attention to its pollution properties as the main material constituting the photoconductive layer, but it is preferable to use materials that are as non-pollution-prone as possible. From this point of view, considering the electrical and optical properties of the A-Si layer to be formed, for example, B,
As, P, Sb, etc. are optimal. In addition, it is also possible to control the material to be n-type by, for example, interstitial doping with Li or the like by thermal diffusion or implantation.

The amount of impurity doped into the A-Si layer is
It is determined as appropriate depending on the desired electrical and optical properties, but in the case of impurities in Group A of the periodic table, it is usually 10 ^-6 to 10 ^-3 atomic%, preferably 10 ^-5 to 10 -3 atomic%.
10 ^-4 atomic%, in the case of impurities of group A of the periodic table, usually 10 ^-8 to 10 ^-3 atomic%, preferably 10 ^-8 to
It is desirable to set it to 10 ^-4 atomic%.

The method of doping these impurities into the A-Si layer differs depending on the manufacturing method adopted when forming the A-Si layer. This is detailed in . In an image forming member in which the layer made of an organic compound or the A-Si layer has a free surface, and the free surface is subjected to charging treatment for forming an electrostatic image, a support and the support are used. It is more preferable to provide a barrier layer between the layer provided above and the barrier layer which functions to prevent injection of carrier from the support side during charging treatment during electrostatic image formation. The type of support selected and the material forming the barrier layer that acts to prevent carrier injection from the support side include the type of support and A-Si.
An appropriate one is selected and used depending on the electrical characteristics of the layer or the layer formed on the support in the layer consisting of an organic compound. Examples of such barrier layer forming materials include inorganic insulating compounds such as Al ₂ O ₃ , SiO, and SiO ₂ , organic insulating compounds such as polyethylene, polycarbonate, polyurethane, and parylene, Au, Ir, Pt, Rh, Metals such as Pd and Mo.

In the present invention, the layer consisting of an organic compound is A
- The carriers generated in the Si-based layer are injected efficiently and the layer is for effectively transporting the injected carriers; The material is selected and the material is bonded to the A-Si layer so that a good contact condition is formed so that carrier injection from the A-Si layer can be carried out smoothly.

In order to form a layer made of an organic compound that satisfies these conditions, A-
In the inner layer or outer layer constituting the Si-based layer, the layer bonded to the layer consisting of an organic compound is n ⁺
In the case of type, n-type, or i ^- type, the hole mobility is relatively large compared to the electron mobility;
In the case of type or i type, one having a relatively large electron mobility relative to hole mobility is selected and used. Many of these materials have film-forming properties, adhesive properties, and the required resistance.
A number of organic compounds are mentioned as suitable.

However, on the already formed organic compound layer, A
In the case where a -Si-based layer is to be formed, as will be clear from the following explanation, it is necessary to select a heat-resistant organic compound as the organic compound.

Most of these organic compounds can be dissolved in a suitable solvent and formed into a layer by a conventional coating method such as a doctor blade method or dipping method.

Examples of organic compounds with relatively high hole mobility that can be effectively used in the present invention include:
PVK, carbazole, N-ethylcarbazole, N-isopropylcarbazole, N-phenylcarbazole, tetraphenylpyrene, 1-methylpyrene, perylene, chrysene, atracene,
Tetracene, tetraphene, 2-phenylnaphthalene, azapyrene, fluorene, fluorenone,
1-ethylpyrene, acetylpyrene, 2,3-benzoglycerin, 3,4-benzopyrene, 1,4
- Organic photoconductive materials such as propopyrene, phenylindole, polyvinylpyrene, polyvinyltetracene, polyvinylperylene, polyvinyltetraphene, polyacrylonitrile, etc. may be mentioned. Organic compounds with relatively high electron mobility include PVK: TNF (monomer molar ratio 1:1)
Examples include organic photoconductive materials such as tetranitrofluorenone, dinitroanthracene, dinitroacridene, tetracyanophyllene, and dinitroanthraquinone.

The image forming member 1 shown in FIG. 1 has a layer structure in which an A-Si layer 3 is laminated on a support 2 and a layer 4 made of an organic compound is laminated on the layer 3. Further, a layer 4 is provided between the support 2 and the A-Si layer 3.
A layer A made of an organic compound other than that may be provided. That is, when the layer A provided between the support 2 and the A-Si layer 3 has a relatively high electron mobility, the layer A has a relatively high hole mobility; When layer 4 has relatively high hole mobility, it is a layer with relatively high electron mobility. The material for forming such a layer is selected from the materials mentioned above as the layer 4 forming material.

The layer thickness of the layer consisting of an organic compound is determined based on the characteristics required of the layer to achieve the object of the present invention and the A-Si
Although it is determined appropriately in relation to the system layer, it is usually 5 to 80 μm, preferably 10 to 50 μm.

The electrophotographic imaging member 9 shown in FIG.
A-Si, which has a support 10, a layer 11 made of an organic compound, a depletion layer 15 formed by joining an inner layer 16 and an outer layer 17, in addition to having a surface coating layer 13 having a free surface 14; The system layer 12 is not essentially different from the imaging member 1 shown in FIG. However, the characteristics required of the surface coating layer 13 differ depending on the electrophotographic process to which it is applied. That is, for example, Special Publication No. 42-23910
If an electrophotographic process such as the NP method described in Japanese Patent Publication No. 43-24748 is applied, the surface coating layer 13 is electrically insulating and does not resist when subjected to charging treatment. It is required that the electrostatic charge holding capacity is sufficient and the thickness is above a certain level, but for example, if an electrophotographic process such as the Carlson process is applied, the potential of the bright area after electrostatic image formation is Since it is desirable that the thickness of the surface coating layer 13 be very small, the thickness of the surface coating layer 13 is required to be very thin. In addition to satisfying the desired electrical properties, the surface coating layer 13 should not have any adverse chemical or physical effects on the A-Si layer 12 and should not have any electrical contact with the A-Si layer 12. It is formed taking into consideration contact properties, adhesive properties, moisture resistance, abrasion resistance, cleaning properties, etc.

Typical materials effectively used for forming the surface coating layer 13 include polyethylene terephthalate, polycarbonate, polypropylene, polyvinyl chloride, polyvinylidene chloride,
Polyvinyl alcohol, polystyrene, polyamide, polytetrafluoroethylene, polytrifluorochloroethylene, polyvinyl fluoride, polyvinylidene fluoride, hexafluoropropylene-tetrafluoroethylene copolymer, trifluoroethylene-vinylidene fluoride copolymer , synthetic resins such as polybutene, polyvinyl butyral, and polyurethane, and cellulose derivatives such as diacetate and triacetate. These synthetic resins or cellulose derivatives may be formed into a film and laminated onto the A-Si layer 12, or a coating liquid thereof may be formed and applied onto the A-Si layer 12. It may be coated to form a layer.

The layer thickness of the surface coating layer 13 is appropriately determined depending on the desired characteristics and the material used, but is usually about 0.5 to 70 μm. In particular, when the surface coating layer 13 is required to function as the above-mentioned protective layer, it is usually set to 10μ or less, and conversely, when the surface coating layer 13 is required to function as an electrical insulating layer, it is set to the normal thickness. In this case, it is considered to be 10μ or more. However, the layer thickness value that differentiates this protective layer from the electrically insulating layer depends on the materials used, the applied electrophotographic process,
The value of 10 μ is not an absolute value because it varies depending on the structure of the designed electrophotographic image forming member.

The support 2 may be electrically conductive or electrically insulating. Examples of the conductive support include stainless steel, Al, Cr, Mo, Au, Ir, Nd, Te, V,
Examples include metals such as Ti, Pt, and Pb, and alloys thereof. Polyester as an electrically insulating support;
Films or sheets of synthetic resins such as polyethylene, polycarbonate, cellulose triacetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, glass, ceramic, paper, etc. are usually used. It is desirable that at least one surface of these electrically insulating supports is electrically conductive treated.

For example, if it is glass, its surface is conductive treated with In ₂ O ₃ or SnO ₂ , or if it is a synthetic resin film such as polyester film, it is treated with Al, Ag,
Pb, Zn, Ni, Au, Cr, Mo, Ir, Nb, Ta, V,
Vacuum evaporation, electron beam evaporation with metals such as Ti and Pt,
The surface is made conductive by sputtering or by laminating with the metal. The shape of the support may be any shape, such as a cylinder, a belt, or a plate, and the shape is determined depending on the need. In the case of continuous high-speed copying, an endless belt or a cylindrical shape is used. It is desirable to do so. The thickness of the support is determined appropriately so that the desired image forming member is formed, but when flexibility is required as an image forming member, the support function can be fully demonstrated. Within this range, it is made as thin as possible. However, in such cases, from the viewpoint of manufacturing and handling of the support, mechanical strength, etc., it is usually 10μ.
This is considered to be the above.

The amount of H contained in the inner layer and outer layer constituting the A-Si layer, which is one of the necessary conditions for achieving the object of the present invention, is within the above numerical range,
The content is determined as appropriate so that the properties required for the layer are satisfied within the range, but the important thing is that the contained H does not impart the required properties. It must be contained in a state that effectively contributes to the

In addition, A-Si, which becomes the inner layer or outer layer, is another necessary condition for achieving the object of the present invention.
The concentration of the impurity doped into the layer is within the numerical range described above, and the doping amount is determined as appropriate so as to satisfy the characteristics required for the amount within the range. However, in order to form a particularly effective depletion layer, It is more preferable to determine the values of a and Nd such that the values are within the following ranges.

In other words, when a predetermined reverse bias voltage is applied to the depletion layer, avalanche destruction and tunneling phenomena do not occur. The upper limit of this value is determined, and is usually set at 10 ^-18 cm ^-3 . As a lower limit, in the A-Si layer to be formed,
The value is larger than the number N of free dangling bonds of Si per unit volume, and preferably 1/2 of N.
It is desirable that the value be larger by an order of magnitude or more, and optimally by one order or more.

Next, when manufacturing the electrophotographic image forming member of the present invention, the case where the A-Si layer is manufactured by the glow discharge method and the sputtering method will be explained.

FIG. 3 is a schematic illustration of a glow discharge deposition apparatus for producing an A-Si layer by an inductance type (inductively coupled) log glow discharge method.

18 is a glow discharge deposition tank, inside which A
- The substrate 19 for forming the Si-based layer is the fixing member 20
A heater 21 for heating the substrate 19 is installed on the lower side of the substrate 19. An induction coil 23 connected to a high frequency power source 22 is wound around the upper part of the deposition tank 18. When the high frequency power source 22 is turned on, the induction coil 23 is connected to a high frequency power source 22.
High frequency power is applied to the deposition tank 18 to generate a glow discharge within the deposition tank 18. Sediment tank 18
A glass introduction tube is connected to the upper end of the
Gas in each of the gas cylinders 24, 25, and 26 is introduced into the deposition tank 18 when necessary. Reference numerals 27, 28, and 29 are flowmeters for detecting the flow rate of gas; 30, 31, and 32 are inflow valves;
3, 34, and 35 are outflow valves, and 36 is an auxiliary valve.

Further, the lower end of the deposition tank 18 is connected to an exhaust device (not shown) via a main valve 37. 45 is a leak valve for breaking the vacuum inside the deposition tank 18.

Using the glow discharge device of FIG.
In order to form an A-Si layer with desired characteristics thereon, first, the substrate 19 that has been subjected to a predetermined cleaning treatment is fixed to the fixing member 20 with the cleaned surface facing upward.

To clean the surface of the substrate 19, a commonly used method, for example, a chemical treatment method using an alkali or an acid, is employed. Alternatively, it may be installed at a predetermined position in the deposition tank 18 that has been cleaned to some extent, and glow discharge treatment may be performed before forming the A-Si layer thereon. In this case, the process from the bulk cleaning treatment of the substrate 19 to the formation of the A-Si layer can be carried out in the same system without breaking the vacuum, making it possible to avoid dirt and impurities from adhering to the cleaned substrate surface. .
After fixing the substrate 19 to the fixing member 20, the main valve 37 is fully opened to drain the air in the deposition tank 18 in the direction indicated by the arrow A.
Evacuate as shown in the figure to create a vacuum of about 10 ^-5 torr.

Next, the auxiliary valve 36 is fully opened, followed by the outflow valves 33, 34, 35, and the inflow valves 30, 31, 3.
2 is fully opened, and the insides of flow meters 27, 28, and 29 are also evacuated. After that, when the inside of the deposition tank 18 reaches a predetermined degree of vacuum, the auxiliary valve 36, the inflow valves 30, 3
1, 32, close the outflow valves 33, 34, 35. Subsequently, the heater 21 is ignited to heat the substrate 19, and once it reaches a predetermined temperature, it is maintained at that temperature. The gas cylinder 24 is for raw material gas for forming A-Si, for example, SiH ₄ , Si ₂ H ₆ , Si ₄ H ₁₀ or
Mixtures of these are stored. In addition, the cylinders 25 and 26 have an A-Si layer to be formed.
For source gas to introduce impurities into the layer to control the type of PH ₃ , P ₂ H ₄ ,
_{B2H6 , AsH3,} etc. are stored.

After confirming that the substrate 19 has reached a predetermined temperature, the valve 38 of the cylinder 22 is opened, the pressure of the outlet pressure gauge 41 is adjusted to the predetermined pressure, and then the inflow valve 30 is gradually opened to increase the temperature inside the flow meter 27. A raw material gas for forming a-Si, such as SiH _4, is flowed into the wafer. Subsequently, the auxiliary valve 36 is opened to a predetermined position, and the flow rate of the gas supplied from the cylinder 24 into the deposition tank 18 is adjusted by gradually opening the outflow valve 33 while observing the value indicated by the Villany gauge 44. . If the above-mentioned impurity is not doped into the A-Si layer to be formed, the deposition tank 1
At the time when the raw material gas for A-Si formation is introduced from the cylinder 24 into the chamber 8, the main valve 37 is adjusted while watching the Billany gauge 44 to obtain a predetermined degree of vacuum, normally, A- The gas pressure when forming the Si layer is maintained at 10 ^-2 to 3 torr. Next, sedimentation tank 1
8 A high frequency power source 22 is connected to the induction coil 23 wound outside.
When a glow discharge is generated in the deposition tank 18 by supplying high frequency power at a predetermined frequency, usually 0.2 to 30 MHz, raw material gas for forming A-Si, e.g.
The SiH ₄ gas is decomposed and Si is deposited on the substrate 19 to form an inner layer.

When introducing impurities into the A-Si layer to be formed, an impurity-generating gas may be introduced into the deposition tank 18 from the cylinder 25 or 26 at the time of forming the A-Si layer. In this case, for example, by appropriately adjusting the outflow valve 34, the amount of gas introduced into the deposition tank 18 from the cylinder 25 can be appropriately controlled. Therefore, not only can the amount of impurities introduced into the A-Si layer to be formed be arbitrarily controlled, but also the amount of impurities can be easily changed in the thickness direction of the A-Si layer. obtain.

After first forming an internal layer to a predetermined thickness on the substrate 19 as described above, an external layer is formed as follows to form the entire A-Si layer.

First, as a first example, if the internal layer is formed by introducing only the raw material gas for A-Si formation supplied from the cylinder 24 into the deposition tank 18, when forming the external layer, the gas from the cylinder 24 is The raw material gas for forming A-Si is mixed with the raw material gas for impurities from the cylinder 25 or 26 and introduced into the deposition tank 18 to form an outer layer of a different type from the already formed inner layer. do.

As a second example, the inner layer may be exposed to the raw material gas for forming A-Si from the cylinder 24 in the cylinder 25.
The raw material gas for impurities from is mixed into the deposition tank 18.
When the outer layer is formed by introducing the raw material gas for forming A-Si from the cylinder 24 or the raw material gas for forming A-Si from the cylinder 24 and the impurity from the cylinder 26, The raw material gases are mixed and introduced into the deposition tank 18 to form an outer layer that is different in type from the inner layer that has already been formed.

As a third example, the internal layer is deposited in a deposition tank 1 using a mixed gas of a raw material gas for A-Si formation from a cylinder 24 and a raw material gas for impurities from a cylinder 25, for example.
8 and then forming the internal layer means that a mixed gas with a different mixing ratio of the raw material gas for A-Si formation and the raw material gas for impurities is introduced into the deposition tank 18. to form the outer layer.

By forming the inner layer and the outer layer by the method described above, a depletion layer is formed at the junction between the inner layer and the outer layer, thereby producing an electrophotographic image forming member as an object of the present invention. This means that an A-Si layer is formed.

In order to form a photoconductive layer having two depletion layers, such as p-i-n, n-i-p, etc., one of the three methods described above should be selected as desired. It's a good thing.

In the glow discharge vacuum deposition apparatus shown in Figure 3, an RF (radio frequency) inductance type glow discharge method is adopted, but other glow discharge methods such as RF capacitance type and DC bipolar type are used. A discharge method is also adopted.

Since the characteristics of the A-Si layer to be formed largely depend on the substrate temperature during growth, it is preferable to strictly control the characteristics. In the present invention, the substrate temperature is usually
By setting the temperature in the range of 50 to 350°C, preferably 100 to 200°C, an A-Si layer having effective characteristics for electrophotography is formed. Furthermore, the substrate temperature is A-
It is also possible to change it continuously or intermittently during the formation of the Si layer to obtain desired characteristics.

Furthermore, the growth rate of the A-Si layer is also a factor that greatly influences the physical properties of the A-Si layer, and in order to achieve the purpose of the present invention, the growth rate is usually 0.5 to 100 Å/sec, preferably 1.
It is preferable to set it to 50 Å/sec.

FIG. 4 is a schematic explanatory diagram showing one of the apparatuses for manufacturing the image forming member of the present invention by a sputtering method.

46 is a vacuum deposition tank, inside of which A-Si is deposited.
A substrate 47 for forming a system layer is fixed to a conductive fixing member 48 that is electrically insulated from the deposition tank 46 and placed at a predetermined position. A heater 49 for heating the substrate 47 is arranged below the substrate 47, and a heater 49 is arranged above the substrate 47 at a predetermined interval.
A polycrystalline or single-crystalline silicon target 50 is attached to a sputtering electrode 51 and placed at a position facing the sputtering electrode 51 .

A high frequency voltage is applied by a high frequency power supply 79 between the fixing member 48 on which the substrate 47 is installed and the silicon target 50.
Further, the deposition tank 46 includes cylinders 52, 53, 54,
55 are respectively inlet valves 56, 57, 58, 5
9, flow meters 60, 61, 62, 63, outflow valves 64, 65, 66, 67, auxiliary valve 68
are connected through the cylinders 52, 53, 5.
4 and 55, desired gases are introduced into the deposition tank 46 when necessary.

Now, in order to form an A-Si layer having a depletion layer on the substrate 47 using the apparatus shown in FIG. , evacuate using a suitable exhaust device, then auxiliary valve 68 and inlet valves 56-5.
9. Fully open the outflow valves 64 to 67 to remove the sedimentation tank 46.
Create a specified degree of vacuum inside.

Next, the heater 49 is ignited to heat the substrate 47 to a predetermined temperature. A by sputtering method
- When forming the Si layer, the heating temperature of this substrate 47 is usually 50 to 350°C, preferably 100 to 200°C. This substrate temperature affects the forming speed of the A-Si layer, the structure of the layer, the presence or absence of voids, etc.
Since it is one of the elements that determines the physical properties of the layer, sufficient control is required. Further, the substrate temperature may be kept constant during the formation of the A-Si layer, or may be raised, lowered, or raised or lowered as the A-Si layer grows. For example, at the beginning of the formation of the A-Si layer, the substrate temperature is kept at a relatively low temperature _T1 , and once the A-Si layer has grown to a certain extent, the substrate temperature is raised to a temperature _T2 higher than _T1 . -Si layer is formed, and at the final stage of A-Si layer formation, the substrate temperature is lowered again to a temperature _T3 lower than _T2 , thereby forming an A-Si layer. By doing so, the electrical and optical properties of the A-Si layer can be changed uniformly or continuously in the layer thickness direction.

In addition, since the layer growth rate of A-Si is slower than that of other materials such as Se, when the layer thickness is increased, the A-Si formed at the initial stage of layer formation (A-Si near the substrate side) ), there is a strong possibility that the characteristics at the initial stage of layer formation will change until the end of layer formation, so in order to form an A-Si layer with uniform characteristics in the thickness direction, it is necessary to It is desirable to form the layer while increasing the substrate temperature from the time to the end of the layer formation. This substrate temperature control operation is also applied when employing the glow discharge method.

After detecting that the substrate 47 has been heated to a predetermined temperature, the inflow valves 56 to 59 and the outflow valve 64
~67, close the auxiliary valve 68.

Next, while watching the outlet pressure gauge 76, the valve 71 is gradually opened to adjust the outlet pressure of the cylinder 53 to a predetermined pressure. Subsequently, the inflow valve 57 is fully opened to allow atmospheric gas, such as Ar gas, to flow into the flow meter 61. After that, auxiliary valve 6
8 is fully opened, and then atmospheric gas is introduced into the deposition tank 47 while adjusting the main valve 69 and the outflow valve 65, and the interior of the deposition tank 47 is maintained at a predetermined degree of vacuum.

Next, while watching the outlet pressure gauge 75,
1 gradually to adjust the outlet pressure of the cylinder 52. Subsequently, the inflow valve 56 is fully opened to allow H ₂ gas to flow into the flow meter 60. Next, H ₂ gas is introduced into the deposition tank 47 while adjusting the main valve 69 and the outflow valve 64 to maintain a predetermined degree of vacuum. The introduction of this H ₂ gas into the deposition tank 47 is as follows:
This step is omitted if there is no need to include H in the A-Si layer formed as an internal layer on the substrate 47. The flow rate of atmospheric gases such as H ₂ gas and Ar gas into the deposition tank 47 is appropriately determined so that an A-Si layer with desired physical properties is formed. For example, when mixing atmospheric gas and H ₂ gas, the pressure of the mixed gas in the deposition tank 47 is a degree of vacuum, usually 10 ^-3 ~
10 ⁻¹ torr, preferably 5×10 ⁻³ to 3×10 ⁻² torr. Ar gas can also be replaced with rare gas such as He gas.

If the A-Si layer to be formed is not forcibly doped with the above-mentioned impurities, atmospheric gas and H ₂ gas or atmospheric gas are introduced into the deposition tank 47 until a predetermined degree of vacuum is reached, and then a high-frequency power supply is applied. 79
, the fixing member 48 on which the substrate 47 is installed and the sputtering electrode 5 are connected at a predetermined frequency and voltage.
A high frequency voltage was applied between 1 to cause a discharge, and the resulting
For example, a silicon target is sputtered with ions of an atmospheric gas such as Ar ions to form an A-Si layer as an internal layer on the substrate 47.

When introducing impurities into the A-Si layer to be formed, raw material gas for impurity formation may be introduced from the cylinder 53 or 54 into the deposition tank 49 at the time of forming the A-Si layer. The introduction method in this case is the same as that described in FIG.

After first forming an inner layer to a predetermined thickness on the substrate 47 as described above, an outer layer is formed on the inner layer in the same manner as described with reference to FIG.

In the explanation of FIG. 4, a sputtering method using high frequency electric field discharge is used, but a sputtering method using DC electric field discharge may also be adopted. In the sputtering method using high frequency voltage application,
Its frequency is usually 0.2~30MHz, preferably 5~
20MHz, and the discharge current density is usually 0.1 to 10
mA/cm ² , preferably 1 to 5 mA/cm ² . Also, in order to obtain sufficient power, usually
The voltage is preferably adjusted to 100-5000V, preferably 300-5000V.

A- when manufactured by sputtering method
The growth rate of the Si layer is mainly determined by the substrate temperature and discharge conditions, and is one of the major factors that influences the physical properties of the formed layer. The forming speed of the A-Si layer to achieve the purpose of the present invention is usually 0.5 to 100 Å/sec, preferably 1 to 50 Å/sec.
It is desirable that this is done. In the sputtering method, as in the glow discharge method, the A-Si layer formed can be adjusted to be n-type or p-type by doping with impurities. The method of introducing impurities is the same in the sputtering method as in the glow discharge method. For example, substances such as PH ₃ , P ₂ H ₄ , B ₂ H ₆ are deposited in a gaseous state during the formation of the A-Si layer. The A-Si layer is introduced into the tank 43 and doped with P or B as an impurity. In addition, impurities may be introduced into the formed A-Si layer by ion implantation.

Example 1 Using the apparatus shown in FIG. 3 installed in a completely shielded clean room, an electrophotographic image forming member was produced by the following operations.

A molybdenum plate (substrate) 19 with a diameter of 0.2 mm and a thickness of 5 cm whose surface was cleaned was placed in a glow discharge vacuum deposition tank 1.
It was firmly fixed to a fixing member 20 at a predetermined position within 8. The substrate 19 was heated with an accuracy of ±0.5° C. by the heater 21 within the fixing member 20. Temperature was measured directly on the back side of the substrate by a thermocouple (alumel-chromel). Next, after confirming that all valves in the system were closed, the main valve 37 was fully opened to evacuate the tank 18 to a degree of vacuum of approximately 5 x 10 ^-6 torr. After that, the input voltage of the heater 21 is increased, and the input voltage is changed while detecting the molybdenum substrate temperature.
It was stabilized until it reached a constant value of 150°C.

After that, the auxiliary valve 36 and then the outflow valve 3
After closing 3, 34, and 35, silane gas (purity
99.999%) The valve 38 of the cylinder 24 was opened, the pressure of the outlet pressure gauge 41 was adjusted to 1 Kg/cm ² , and the inflow valve 30 was gradually opened to allow silane gas to flow into the flow meter 27 . Subsequently, gradually open the outflow valve 33, then gradually open the auxiliary valve 36, and adjust the opening of the auxiliary valve 36 while watching the reading on the Billany gauge 44 until the inside of the tank 18 reaches 1.
The auxiliary valve 36 was opened until ×10−2 torr. After the internal pressure of tank 18 has stabilized, main valve 3
7 is gradually closed and the indication of Villany gauge 44 is
The aperture was narrowed down to 0.5 torr. After confirming that the internal pressure has stabilized, turn on the switch of the high frequency power supply 22, apply 5MHz high frequency power to the induction coil 23, and generate a glow discharge inside the coil in the tank 18 (at the top of the tank). The input power was 30W. In order to grow an A-Si layer on the substrate under the above conditions, the same conditions were maintained for 1 hour (formation of internal layer).
After that, the high frequency power supply 20 is turned off and the glow discharge is stopped, and diborane gas (purity
99.999%) Open the valve 39 of the cylinder 25, adjust the pressure of the outlet pressure gauge 42 to 1 Kg/cm ² , gradually open the inflow valve 31 to allow diborane gas to flow into the flow meter 28, and then gradually open the outflow valve 34. The opening of the outflow valve 34 was set so that the flow meter 28 read 0.08 vol% of the flow rate of the silane gas, and the outflow valve 34 was stabilized.

Subsequently, the high frequency power supply 22 was turned on again to restart the glow discharge. After continuing the glow discharge in this way for another hour (formation of the outer layer),
Turn off the heater 21 and turn off the high frequency power source 2.
2 is also turned off, and after waiting for the substrate temperature to reach 100℃, the outflow valves 33 and 34 and the auxiliary valve 3 are turned off.
6 was closed, and then the main valve 37 was fully opened to bring the inside of the tank 18 to 10 ^-5 torr or less.The main valve 37 was then closed, and the inside of the tank 18 was brought to atmospheric pressure by the leak valve 45, and the substrate was taken out. in this case,
The total thickness of the A-Si layer formed on the substrate was about 3 microns.

Next, a coating solution prepared by dissolving PVK in toluene was applied onto the A-Si layer using a doctor blade method. Next, this was left in an atmosphere at 80° C. for about 2 hours to evaporate the toluene. The thickness of the PVK film after drying was approximately 15μ. The image forming member A thus obtained was subjected to an image forming process as shown below.

First, in the dark, a negative corona discharge was applied to the image forming surface with a power supply voltage of 5500V, and then a
Image exposure was performed from the image forming surface with exposure light of lux.sec to form an electrostatic image, and the electrostatic image was developed with positively charged toner by a cascade method to transfer and fix it onto a transfer paper. At this time, although the processing time from charging to completion of development was approximately several seconds, a highly clear transferred image with high resolution was obtained. Further, even when the processing time exceeded 10 seconds, almost no decrease in the contrast of the transferred image was observed.

Example 2 An aluminum substrate was prepared in the same manner as in Example 1, except that glow discharge was performed in a state where B ₂ H ₆ gas was mixed with SiH ₄ gas at a ratio of 0.01 vol% to form an external layer. Thickness 3 with a depletion layer formed in the layer
A μ A-Si layer was obtained. On this A-Si layer,
A coating solution obtained by dissolving PVK in toluene was applied using a doctor blade method, and then left in an atmosphere at 80° C. for about 2 hours to evaporate the solvent. The layer thickness of PVK after drying was approximately 20μ. The image forming member B thus formed was negatively corona charged with a power supply voltage of 6000 V in the dark, and then 15
Image exposure is performed from the image forming surface with an exposure amount of lux.sec to form an electrostatic image, and the electrostatic image is developed with positively charged toner using a cascade method to be transferred and fixed onto transfer paper. Everywhere I went, I was able to obtain high-resolution and extremely clear images.

Example 3 Surface treated with 1% NaOH solution, thoroughly washed with water and dried to clean the surface, 1 mm thick.
An aluminum substrate with a size of 10 cm x 5 cm was prepared, and a coating solution obtained by dissolving polyacrylonitrile in dimethylformamide was applied onto it using a doctor blade method. Next, this was left in an atmosphere of about 80°C for about 1 hour to evaporate dimethylformamide, and then left in an atmosphere of about 250°C for about 2 hours for the purpose of heat treatment. The thickness of the polyacrylonitrile layer after drying was 20μ. On the polyacrylonitrile layer thus obtained, an A-Si layer was formed by sputtering as described below using the apparatus shown in FIG.

First, a substrate 47 having a polyacrylonitrile layer
The fixing member 4 at a predetermined position in the vacuum deposition tank 47
8 was firmly fixed at a predetermined position with the polyacrylonitrile layer facing upward and spaced approximately 10 cm from the heater 49. On the electrode facing the substrate 47, a polycrystalline silicon plate (99.999% purity) target 50 was fixed parallel to and facing the substrate 47 at a distance of about 4.5 cm.

The inside of the tank 46 is once evacuated to about 5×10−7 torr by fully opening the main valve 69 (at this time,
All valves in the system are closed), auxiliary valve 6
8 and the outflow valves 64, 65, 66, 67 are opened and the outflow valves 64, 6 are sufficiently degassed.
5, 66, 67 and auxiliary valve 68 were closed.

The substrate 47 was heated by inputting a heater power source and maintained at 200°C. and hydrogen (purity
99.99995%) The valve 71 of the cylinder 52 was opened, and the outlet pressure was adjusted to 1 Kg/cm ² using the outlet pressure gauge 75. Subsequently, the inflow valve 56 was gradually opened to allow hydrogen gas to flow into the flow meter 60, and then the outflow valve 64 was gradually opened, and the auxiliary valve 68 was further opened.

While detecting the internal pressure of the tank 46 with the pressure gauge 70, the outflow valve 64 was adjusted to a degree of vacuum of 5×10 ⁻⁵ torr. Next, open the valve 72 of the argon (99.9999% purity) gas cylinder 53, and check the outlet pressure gauge 76.
After the reading was adjusted to 1 Kg/cm ² , the inlet valve 57 was opened, and then the outlet valve 65 was gradually opened to allow argon gas to flow into the tank 46. The outflow valve 65 is gradually opened until the pressure gauge 70 indicates 5×10 ^-4 torr. After the flow rate stabilizes in this state, the main valve 69 is gradually closed and the internal pressure of the tank 46 is reduced to 1× The aperture was narrowed down to 10 ^-2 torr. Next, open the valve 73 of the diborane gas (purity 99.9995%) cylinder 54, adjust the outlet pressure gauge 77 to 1 Kg/cm ² and open the inflow valve 58, then gradually open the outflow valve 66 so that the reading on the flow meter 62 becomes The outflow valve 66 was adjusted so that hydrogen gas was introduced at a flow rate of approximately 1.0 vol% of the flow rate indicated by the hydrogen gas flow meter 60. After confirming that the flow meters 60, 61, and 62 are stable, the high frequency power source 79 is turned on, and a 13.56MHz,
500V, 1.6KV AC power was input. Under these conditions, the layers were formed while performing matching so that stable discharge could continue. Discharge was continued in this manner for 40 minutes to form an inner layer. After that, turn on the high frequency power supply 79.
The battery was turned off and the discharge was temporarily stopped. Subsequently, the outflow valves 64, 65, and 66 were closed, and the main valve 69 was fully opened to remove the gas from the tank 46.
Vacuum was applied to 10 ^-7 torr. After that, as in the case of internal layer formation, hydrogen gas and Ar gas are introduced and the opening of the main valve 69 is adjusted to increase the internal pressure of the tank 46 by 2×.
10 ^-2 torr. Subsequently, phosphine gas (purity
99.9995%) Open the valve 74 of the cylinder 55, adjust the outlet pressure so that the reading on the outlet pressure gauge 78 is 1 Kg/cm ² , open the inflow valve 59, then gradually open the outflow valve 67, and adjust the outlet pressure to the flow meter 63. Therefore, the flow rate was adjusted to be 1.0% of the hydrogen gas flow rate. After the gas flow rates of hydrogen, argon, and phosphine became stable, the high frequency power source 79 was turned on again, and 1.6 KV was applied to restart the discharge. After continuing to discharge for 40 minutes under these conditions, turn on the high frequency power supply 79.
The power supply to the heating heater 49 was also turned off. After waiting for the substrate temperature to fall below 100° C., the outflow valves 64, 65, 67 and the auxiliary valve 68 were closed, and then the main valve 69 was fully opened to vent the gas in the tank 46. Then main valve 6
9 was closed and the leak valve 80 was opened to leak to atmospheric pressure, and then the substrate on which the A-Si layer was formed was taken out.

In this case, the thickness of the formed A-Si layer is 2
It was μ.

This sample was designated as image forming member C. This image forming member C was positively corona charged with a power supply voltage of 6000 V in the dark, and then image exposure was performed from the image forming surface at an exposure amount of 15 lux.sec to form an electrostatic image. When the image was developed with negatively charged toner using the cascade method and transferred and fixed onto transfer paper, an extremely clear image with high resolution was obtained.

Example 4 After forming a polyacrylonitrile layer (layer thickness approximately 15 μm) and an A-Si layer (layer thickness 1 μm) on an Al substrate in the same manner as in Example 3, Example 2 was further formed on the layer. PVK; TNF was applied in a similar manner (layer thickness approximately 15μ).

When image forming member D thus manufactured was subjected to image processing in the same manner as in Example 3, a high quality transferred image was obtained.

Example 5 Sheet of polyethylene terephthalate (thickness
An image forming member E was obtained in the same manner as in Example 1, except that the substrate was a substrate having a thin layer of aluminum (100μ) deposited on it. Image processing was performed in the same manner as in Example 1, except that image exposure was performed from the substrate side using this. The resulting transferred image was of high quality.

Example 6 After forming a polyacrylonitrile layer (about 15μ thick) and an A-Si layer (about 1μ thick) on an Al substrate in the same manner as in Example 3, a polycarbonate layer was formed on the A-Si layer. A transparent insulating layer was formed by applying a resin to a thickness of 15 μm after drying, and an image forming member F was obtained. The surface of the insulating layer of this image forming member is firstly charged by negative corona discharge at a charging voltage of 6000V, and at the same time, the entire surface of the insulating layer is irradiated with light.After about 5 seconds, secondary charging is performed by applying a charging voltage of 6,000V.
Positive corona discharge is performed at 5500V and at the same time the exposure amount is 20
Image exposure was performed at lux.sec, and then the entire surface of the image forming member was uniformly irradiated to form an electrostatic image. When this was developed with positively charged toner using the cascade method and transferred and fixed onto transfer paper, a clear image with high resolution was obtained.

Example 7 One surface of a cleaned Corning 7059 glass (1 mm thick, 4 x 4 cm, polished on both sides) was coated with ITO by electron beam evaporation.
(In ₂ O ₃ ; SnO ₂ 20; I molding, sintered at 600°C) at 1200 Å
After being vapor-deposited to a layer thickness of
It was placed on the fixing member 20 (see figure) with the ITO vapor deposition surface facing upward. Subsequently, the inside of the glow discharge tank 18 was made into a vacuum of 5×10 ^-6 torr by the same operation as in Example 1, and the substrate temperature was maintained at 170°C. Then, silane gas was flowed, and the inside of the tank 18 was , adjusted to 0.8torr.
At this time, the phosphine gas is further added to the silane gas.
Phosphine gas cylinder 2 so that it is 0.1vol%
6 through the valve 40, the inflow valve 3 at a gas pressure of 1 Kg/cm ² (reading of the outlet pressure gauge 41).
2. By adjusting the outflow valve 35, a mixture of silane gas and silane gas was flowed into the tank 18 based on the readings of the flow meter 29. The gas inflow becomes stable and the tank internal pressure becomes constant.
After the substrate temperature stabilized at 190° C., the high frequency power supply 22 was turned on in the same manner as in Example 1 to start glow discharge. After sustaining the glow discharge for 30 minutes under these conditions, the high frequency power source 22 was turned off to stop the glow discharge and complete the formation of the inner layer.
After that, the outflow valves 33 and 35 are closed, the auxiliary valve 36 and the main valve 37 are fully opened, and the tank 18
The inside was evacuated to 5×10 ^-6 torr. Thereafter, the auxiliary valve 36 and the main valve 37 were closed, the outflow valve 33 was gradually opened, and the auxiliary valve 36 and the main valve 37 were restored to the same flow rate state of the silane gas as at the time of forming the inner layer described above. Next, the high-frequency power supply 22 is turned on again to restart the glow discharge, and after this state is maintained for one hour, the heating heater 9 and the high-frequency power supply 22 are turned off, and the substrate temperature is waited for to reach 100°C. hand,
The outflow valve 33 is closed, the main valve 37 and the auxiliary valve 36 are fully opened, and the inside of the tank 18 is temporarily reduced to 10 ^-5 torr.
After the following, close the main valve 37 and
8 was leaked using the leak valve 45, and the substrate was taken out. The total thickness of the formed A-Si layer is approximately 3.5μ
It was hot.

Example 1
A PVK layer having a thickness of 30 μm was formed in the same manner as described above to form an image forming member G. The image forming member G thus obtained was subjected to an image forming test. When image formation was performed using a combination of 6KV corona charging and exposure chargeable developer, it was possible to obtain high-quality images that could be used for practical purposes.

[Brief explanation of the drawing]

FIGS. 1 and 2 are schematic cross-sectional views showing an example of the structure of an electrophotographic image forming member of the present invention, and FIGS. 3 and 4 are views for manufacturing an electrophotographic image forming member of the present invention. FIG. 2 is a schematic explanatory diagram showing an example of a device for 1, 9... Image forming member for electrophotography, 2, 10...
...Support, 3,12...A-Si layer, 4,11...
...Organic compound layer, 5, 14...Free surface, 13...
...Surface coating layer, 18,46...Vacuum deposition tank.

Claims (1)

[Claims] 1. An amorphous silicon layer having a depletion layer, generating movable carriers by electromagnetic wave excitation, and containing 1 to 40 atomic percent of hydrogen, and the carriers generated in the layer. a layer of organic compounds injected and for transporting the injected carrier;
An electrophotographic image forming member comprising: 2. The electrophotographic image forming member according to claim 1, wherein the organic compound has a relatively high electron mobility. 3. The electrophotographic image forming member according to claim 1, wherein the organic compound has a relatively high hole mobility. 4. Claims 2 to 3, wherein the layer made of the organic compound is provided as a layer through which irradiated electromagnetic waves can be transmitted so that a sufficient carrier can be generated in the amorphous silicon layer.
The electrophotographic image forming member according to any one of Items 1 to 9. 5. Electrophotographic image formation according to any one of claims 1 to 4, wherein the depletion layer is provided as a layer that generates a movable carrier under the action of irradiated electromagnetic waves. Element. 6 The depletion layer is provided at a junction formed by laminating two different types of amorphous silicon layers of p ⁺ type, p type, n type, n ⁺ type, and i type. The electrophotographic imaging member according to scope 5. 7. The electrophotographic image forming member according to claim 6, wherein one of the two different amorphous silicon layers is p ⁺ type or p type, and the other is n ⁺ type or n type. 8. The electrophotographic device according to claim 6, wherein one of the two different amorphous silicon layers is i-type and the other is one of p ⁺ type, p type, n type, and n ⁺ type. Imaging member. 9 Regarding the depletion layer, the layer on the side where the electromagnetic waves are irradiated is provided as a layer through which the irradiated electromagnetic waves can pass so that a sufficient carrier can be generated in the depletion layer. The electrophotographic image forming member according to any one of items 6 to 8. 10. The electrophotographic image forming member according to claim 1, wherein a barrier layer is provided on a side of the amorphous silicon layer opposite to the layer made of the organic compound. 11. The electrophotographic imaging member according to claim 1, further comprising an electrically insulating layer. 12. The electrophotographic image forming member according to claim 1, wherein the amorphous silicon layer and the layer made of an organic compound are provided in this order on a support. 13. The electrophotographic image forming member according to claim 1, wherein the layer made of the organic compound and the amorphous silicon layer are provided in this order on a support.