Bridgestone Corporation

Taro Miyamoto

Hiroaki Wada

Yoshitomo Takahashi

Takahiro Kawagoe

Hiroshi Kaneda

Yoshitomo Masuda

Koji Takagi

Yoshio Takizawa

Gaku Yakushiji

Tadashi Nakajima

Yuko Maeda

Hideyuki Niwa

Yasushi Inoue

Hiroshi Harashima

A wafer employing a silicon carbide sintered body is provided. The density of the silicon carbide sintered body is 2.9 g/cm.sup.3 or more. The silicon carbide sintered body is obtained by sintering a mixture in which silicon carbide powder and a non-metal-based sintering additive are mixed uniformly. The non-metal-based sintering additive is formed of an organic compound which generates carbon upon heating or the like. As a result, a wafer with excellent heat resistance and acid resistance and which causes little contamination is provided.

Wafer

A silicon carbide sintered body according to the present invention is a silicon carbide sintered body having a density of 2.9 g/cm.sup.3 or higher, obtained by means of hot pressing a mixture of silicon carbide powder and a non-metal-based sintering additive such as an organic compound which produces carbon upon heating at a temperature of 2,000.degree. C. to 2,400.degree. C. and under a pressure of 300 to 700 kgf/cm.sup.2 in a non-oxidizing atmosphere. It is preferable that the silicon carbide powder have an average particle diameter of from 0.01 to 10 .mu.m and that the non-metal sintering additive be a resol type phenol resin. The present invention is to provide a silicon carbide sintered body of high quality which has a high density, a high purity, and a high electrical conductivity and which is useful for semiconductor manufacturing industry.

Process for making a silicon carbide sintered body

A part for an ion implantation device employing a silicon carbide sintered body is provided. The density of the silicon carbide sintered body is 2.9 g/cm.sup.3 or more. The silicon carbide sintered body is obtained by sintering a mixture in which silicon carbide powder and a non-metal-based sintering additive are mixed uniformly. The non-metal-based sintering additive is formed of an organic compound which generates carbon upon heating or the like. As a result, a part for an ion implantation device with excellent heat resistance and ion resistance and which causes little contamination is provided.

Part for ion implantation device

A charging device for electrically charging a photoconductor drum includes a charging member adapted to be placed in contact with the drum and an element for applying voltage between the charging member and the drum. The charging member has a microhardness of 1-65 degrees at its surface in contact with the drum or at least a surface layer of the charging member in contact with the drum is formed of a polyurethane which is prepared from liquid MDI as an isocyanate component and a polyol.

Electrostatic charging member and photoconductor device

A developing roller includes a metal shaft and a conductive resilient sleeve surrounding the shaft and made of a urethane elastomer containing carbon black with at least pH 5. The developing roller is mounted in an electrophotographic apparatus in combination with a latent image-bearing photoreceptor wherein development is carried out using a non-magnetic single-component toner.

Developing roller and apparatus

Growing community of inventors

Yokohama, Japan

Taro Miyamoto