Shin-Etsu Chemical Co., Ltd.

Other

Teruhiko Hirasawa

Toru Yamada

Katsushi Tokunaga

Susumu Sakaguchi

Tadashi Kamioka

Takao Abe

Tsuguo Fukuda

Tetsuya Igarashi

Masafumi Yamaguchi

There can be provided according to the present invention a silicon single crystal produced according to Czochralski method to which Ga (gallium) is added as a dopant characterized in that a resistivity is 5&OHgr;.cm to 0.1&OHgr;.cm and a method for producing a silicon single crystal to which Ga (gallium) is added as a dopant according to Czochralski method characterized in that Ga is added in a silicon melt in a crucible, a seed crystal is brought into contact with the silicon melt and is pulled with rotating to grow a silicon single crystal ingot. Thereby, a silicon single crystal and silicon single crystal wafer and a method for producing them that can produce a solar cell characterized in that photo-degradation is not caused even in the single crystal having high oxygen concentration and a conversion efficiency of optical energy is very high.

Silicon single crystal and wafer doped with gallium and method for producing them

There are disclosed multi-crystalline silicon which is added with Ga (gallium) as a dopant and a method for producing Ga-doped multi-crystalline silicon, which comprises adding Ga to silicon melt in a crucible, which is melted by heating, and cooling the silicon melt to allow growth of multi-crystalline silicon. According to the present invention, there are provided multi-crystalline silicon and a multi-crystalline silicon wafer for producing solar cells showing stable conversion efficiency for light energy without causing photodegradation as well as methods for producing them.

Ga-doped multi-crytsalline silicon, Ga-doped multi-crystalline silicon wafer and method for producing the same

Proposed is a low-cost method for the preparation of a wire-formed crystal of silicon having a diameter of 1 mm or smaller, in which a vertically held starting rod of silicon is melted at one end portion by high-frequency induction heating, a seed crystal is brought into contact with the molten portion and then the seed crystal and the starting silicon rod are pulled apart in the vertical direction at a controlled velocity with a controlled high-frequency power input so that the melt of silicon drawn by the seed crystal is solidified and crystallized into the form of a wire.

Method for the preparation of wire-formed silicon crystal

A novel structure of a silicon solar cell is disclosed, which can be prepared at an outstandingly low cost but can still exhibit good efficiency for the conversion of solar energy to electricity. The silicon solar cell comprises, as an integral body:

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Annaka, Japan

Teruhiko Hirasawa