Fuji Electric Co., Ltd.

Fuji Electric Corporate Research and Developement Ltd.

Toyoki Kazama

Koichi Aizawa

Toshiyuki Iijima

Kenichi Hara

Yukio Takano

Teizo Takahama

Masaharu Namba

Michiro Shimatani

Hideki Kina

Kiyoto Yamaguchi

Yukihisa Tamura

Kunio Sukigara

Tatumi Hieda

Mitsuru Yamauchi

Toshiyuji Iijima

Eizo Tanabe

In the photoreceptor described in the specification, an electroconductive base has an amorphous silicon type photoconductive layer coated over a blocking layer on the base and an amorphous carbon-containing surface layer, coated over a buffer layer on the photoconductive layer, has a hardness on the free surface side which is higher than the hardness on the buffer surface side. Apparatus for preparing the photoreceptor includes a CVD vacuum chamber and an arrangement for supplying selected layer-forming gases to the chamber in a controlled manner.

Electrophotographic photoreceptor

An electrophotographic photoreceptor comprises a conductive base, a photoconductive layer formed of amophous silicon on the conductive base, a buffer layer on the photoconductive layer, and a surface layer covering the photoconductive layer through the buffer layer, wherein the buffer layer is formed of amorphous carbon.

Electrophotographic photoreceptor comprising amorphous silicon and

A photosensitive material comprising a photosensitive layer composed of an amorphous silicon-based material formed on an electrically conductive support, and a surface layer formed on said photosensitive layer, the surface layer being composed of amorphous carbon containing hydrogen and fluorine has improved printing durability and humidity resistance.

Electrophotographic photosensitive material comprising amorphous carbon

Electrophotographic light-sensitive elements according to the invention comprise

Electrophotographic light-sensitive element with amorphous C overlayer

In the specific embodiments described herein, the charge drop resulting from fatigue in an electrophotographic process using an a-Se:H photosensitive member is reduced by a stabilization exposure carried out for one to three cycles prior to use of the member for image formation. Longer wavelength light may be used for the stabilization exposure and shorter wavelength light may be used for the imaging and discharge steps.

Electrophotographic process

Disclosed is a method for removing an amorphous silicon photosensitive layer from the metallic surface (e.g., aluminum or stainless steel) of a substrate used in electrophotography. The amorphous silicon layer is removed by exposing such layer to a plasma generated in a fluorine containing atmosphere. Such a plasma provides a high etch rate for the amorphous silicon layer and an extremely high silicon-to-metal etch selectivity. Therefore, the amorphous silicon layer may be rapidly removed by etching at a high power density without risk of damaging the polished metallic surface of the electrophotographic substrate. Moreover, since the etching automatically stops when the metallic surface is reached, no end-point detection is necessary.

Method for generating substrates of electrophotographic photosensitive

Disclosed are method and apparatus for producing amorphous silicon layers for solar cells or electrophotography by plasma-enhanced chemical vapor deposition (CVD) through glow-discharge decomposition of a reaction gas containing monosilane or a higher order silicon hydride in a reaction chamber. Deposition rate and efficiency of reaction gas usage are improved by the selective removal of hydrogen gas reaction product from the reaction chamber. In one embodiment, a filter which is more permeable to hydrogen gas than to the reaction gas is placed in the vacuum pumping port of the reaction chamber. The filter comprises either a palladium film or a bundle of small diameter tubes made from a polyimide system polymer. In another embodiment of the invention, a porous sintered material containing La-Ni alloy is used to selectively adsorb hydrogen gas in the reaction chamber. In still another embodiment of the invention, a trap which collects reaction gas but passes hydrogen gas is used in the vacuum pump line connected to the chamber. The trap comprises a cell cooled to liquid nitrogen temperature for condensing the reaction gas but not the hydrogen. The collected reaction gas is recycled through the reaction chamber. The removal rate of hydrogen gas is controlled to maintain a desired hydrogen density in the reaction chamber, the hydrogen density being monitored by observing the intensity of hydrogen spectral lines in the glow discharge in the reaction chamber.

Method of producing amorphous silicon layer and its manufacturing

Disclosed is an production method for plasma chemical vapor deposition (CVD) of amorphous silicon films providing improved throughput and film yield. According to the present invention, a glow discharge is generated in a reaction chamber containing a gaseous silicon-containing compound, such as monosilane (SiH.sub.4) or tetraflourosilane (SiF.sub.4), by the imposition of an electric field between a pair of spaced-apart electrodes within the chamber. The electric field is established by connecting an appropriate DC or high frequency driving voltage to one of the pair of electrodes and ground potential to the other. In the case where a high frequency driving voltage is used, connection to the driven electrode is made through a coupling capacitor, and the frequency of the driving voltage is selected such that a DC potential develops between the pair of electrodes. Substrates on which amorphous silicon films are to be deposited are positioned adjacent to each one of the electrodes, and the connections for the driving voltage and ground to the electrodes are periodically reversed during film deposition. In an alternative embodiment of the invention, multiple pairs of electrodes are arranged within the reaction chamber.

Production of amorphous silicon film

Disclosed are method and apparatus for producing highly uniform films of photosensitive materials (e.g., amorphous silicon) for electrophotography on large diameter cylindrical metal substrates (e.g., aluminum or stainless steel) by plasma chemical vapor deposition (CVD). The cylindrical substrate is rotatably mounted in a reaction chamber and serves as an electrode. A hollow metallic second electrode in the reaction chamber coaxially surrounds the substrate and is spaced apart therefrom. Hydrogen gas is first introduced into the inter-electrode space between the substrate and the second electrodes, and a high-frequency electric field is applied to the two electrodes to generate a glow discharge for plasma cleaning of the substrate surface. The hydrogen gas is then pumped out of the reaction chamber, and a reaction gas of monosilane (SiH.sub.4) is then flowed through the inter-electrode space and a glow discharge is again generated between the electrodes to decompose the silane and to cause amorphous silicon to deposit on the surface of the substrate. During deposition both the substrate and the second electrode are electrically heated. The reaction gas is introduced and exhausted in a manner such that reaction gas density in the inter-electrode space is uniform along the axial direction.

Method for producing photosensitive film for electrophotography

A carbon monoxide detecting apparatus is provided which is substantially unaffected by other coexisting gases in the gas atmosphere being sampled. The present invention includes a first carbon monoxide detecting element, a second carbon monoxide detecting element, and a comparing means. The first carbon monoxide detecting element is responsive to carbon monoxide gas and produces a stepwise change in a first film current over a first preselected range of carbon monoxide gas concentration. The second carbon monoxide detecting element is responsive to carbon monoxide gas and produces a stepwise change in a second film current over a second preselected range of carbon monoxide gas. The comparing means is responsive to the first and second film currents and provides an output difference signal .DELTA.E. The amplitude of the output difference signal .DELTA.E is in accordance with the absolute value difference between the first film current and the second film current. The two preselected ranges of carbon monoxide gas concentration can be achieved by appropriately altering the structure of the respective carbon monoxide detecting element and/or by making the substrate temperatures of the two carbon monoxide detecting elements different.

Carbon monoxide detecting apparatus

A carbon monoxide detecting device which exhibits a stepwise change in film current over a preselected range in carbon monoxide concentration is disclosed. According to the present invention, in one embodiment, a first film predominantly of stannic oxide (SnO.sub.2) is formed on an insulating layer, and a second film predominantly of platinum (Pt) is formed on said first film. The second film is of an average film thickness of about 0.3 to 30 platinum atom layers. In another embodiment, gold (Au) is incorporated into said second film, and the second film is of an average film thickness of about 0.3 to 30 platinum atoms and the amount of gold ranges up to 50 atomic percent of the amount of platinum. In a third embodiment, a donor selected from the group consisting of antimony (Sb) and bismuth (Bi) is incorporated into the first film, and an intermediate film predominantly of stannic oxide (SnO.sub.2) having an acceptor selected from the group consisting of platinum (Pt), aluminum (Al), and boron (B) is formed intermediate said first and second films. The first, intermediate, and second films are formed, for example, by a high frequency reactive sputtering method.

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Yokosuka, Japan

Toyoki Kazama