Nippon Steel Corporation

Matsushita Electric Industrial Co., Ltd.

Silicio Ferrosolar S.l.

Jiro Kondo

Goro Saiki

Shinji Tokumaru

Hitoshi Dohnomae

Kenji Kanai

Masaki Okajima

Masataka Hiyoshi

Haruo Shimada

Kensuke Okazawa

Yutaka Kishida

Akihito Kiyose

Atsushi Nogami

Yoshihisa Nakano

Nobuo Honami

Koichi Takeda

Ryuji Watanabe

Tutomu Ooki

Mutsuo Maki

Kazutaka Miyatake

Masahiko Tatsumi

Kozo Onoue

Shigeru Nakazawa

Provided are: a method for manufacturing a highly pure silicon by unidirectional solidification of molten silicon, that can inexpensively and industrially easily manufacture highly pure silicon that has a low oxygen concentration and low carbon concentration and is suitable for applications such as manufacturing solar cells; highly pure silicon obtained by this method; and silicon raw material for manufacturing highly pure silicon. A method for manufacturing highly pure silicon using molten silicon containing 100 to 1000 ppmw of carbon and 0.5 to 2000 ppmw of germanium as the raw material when manufacturing highly pure silicon by unidirectionally solidifying molten silicon raw material in a casting container, the highly pure silicon obtained by this method, and the silicon raw material for manufacturing the highly pure silicon.

Method for manufacturing highly pure silicon, highly pure silicon obtained by this method, and silicon raw material for manufacturing highly pure silicon

The present invention provides a method for removal of boron from metal silicon inexpensively and extremely efficiently by a simple method, specifically, heating metal silicon containing boron as an impurity to its melting point to 2200&#xb0; C. to place it in a molten state, then adding a solid mainly comprised of silicon dioxide and a solid mainly comprised of one or both of a carbonate of an alkali metal or a hydrate of a carbonate of an alkali metal into said molten silicon so as to form a slag and remove the boron in the silicon.

Method for removing boron from silicon

A process for production of Si, characterized by adding an oxide, hydroxide, carbonate or fluoride of an alkali metal element, or an oxide, hydroxide, carbonate or fluoride of an alkaline earth metal element, or two or more of such compounds, to solid SiO in a total molar amount of from 1/20 to 1000 times with respect to the moles of solid SiO, heating the mixture at between the melting point of Si and 2000&#xb0; C. to induce a chemical reaction which produces Si and separating and recovering the Si from the reaction by-product, for the purpose of inexpensively and efficiently producing Si from various forms of solid SiO with no industrial value produced from Si production steps and the like.

Method for production of silicon

It is possible to produce high purity Si by heating solid SiO at a temperature of at least 1000&deg; C. and lower than 1730&deg; C., for a disproportionation reaction in which the SiO solid is decomposed to liquid or solid Si and solid SiO , and the produced Si is separated from the SiO and/or SiO. The SiO solid can be obtained by a process whereby a starting mixture of carbon C, silicon Si or ferrosilicon, or a combination thereof, with SiO is heated to generate SiO gas-containing gas, and the SiO-containing gas is cooled to produce SiO solid.

Production process and apparatus for high purity silicon

A photosynthetic culture system has a culture bath holding an fluid containing plant microorganisms, carbon dioxide supplying means for supplying carbon dioxide to the fluid in the culture bath, light-conducting plate in the form of a flat plate placed oppositely to a light-receiving culture surface existing on the side of said culture bath, and light-receiving panel mounted on the upper end surface of the light-conducting plate. Further said light-conducting plate has the function of turning incident light from said light-receiving panel by right angles to conduct the light uniformly to said light-receiving culture surface of said culture bath.

Photosynthetic culture apparatus and group of photosynthesis culture apparatuses

Silicon carbide particles are produced by reacting a gaseous silicon compound or granular silicon with a carbon compound at a high temperature. In the reaction, the amount of free carbon content in the resultant silicon carbide particles can be controlled by monitoring the amount of unsaturated hydrocarbon such as acetylene, as a by-product. Moreover, silicon carbide particles can contain boron dispersed uniformly in the particles by a two step process comprising first reacting a silicon source and a boron source without a carbon source in a first reaction zone, to form boron-containing silicon particles, and second, reacting the resultant particles with a carbon source in a second reaction zone. Further, the above-mentioned monitoring of an unsaturated hydrocarbon by-product allows the obtaining of silicon carbide particles containing no free carbon, and the silicon carbide particles containing boron in the particles but no free carbon may be sintered without the addition of free carbon, to give a dense sinter.

Processes for producing a high density silicon carbide sinter

Process for producing a boron-containing silicon carbide powder

Process for producing a silicon carbide powder

Ultrafine particles of metals, metallic compounds, and ceramics can be produced by heating a starting material supplied hermetically with a plurality of direct current plasma currents combined at a central axis of a work coil for generating high frequency induction plasma positioned under the direct current plasma generated zone. Apparatuses used therefor are also disclosed.

Process for producing ultrafine particles of metals, metal compounds and

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Futtsu, Japan

Jiro Kondo