Abstract: The present invention provides a method for producing a tantalum or niobium powder which controls releasing and contamination of impurities such as Fe, Ni, Cr, and Mo, which are derived from a reaction vessel, to a range in which characteristics of tantalum or niobium are not influenced. The method for producing a tantalum or niobium powder of the present invention is a method in which a metal salt containing tantalum or niobium is reduced in a diluent salt to obtain a tantalum or niobium powder, wherein a total percentage of moisture in the metal salt and the diluent salt is 0.2% by mass or less, as determined by the Karl Fisher method based on an amount of moisture generated by heating the metal salt and the diluent salt to 600° C.

Abstract: The present invention is a SiC member and fabrication method thereof useful for heat treating semiconductors, wherein at least the surface of the member comprises: CVD-.beta.-phase SiC columnar crystals grown in perpendicular to the surface of the member; and CVD-.alpha.-phase SiC crystals grown up from interface of CVD-.beta.-phase columnar crystals. This structure thereby makes it possible to reduce the infrared ray transmittance of the heat treatment member and facilitates the heating of the heat treatment member by absorbing the infrared rays. Absorption of the IR rays results in favorable the temperature follow-up characteristics during the heat treatment of a semiconductor.