PROBLEM TO BE SOLVED: To obtain a large-scale high-quality silicide bulk crystal by reacting a silicon substrate with a molten liquid of an intermetallic compound.
SOLUTION: The intermetallic compound is the one comprising metals constituting the silicide and an element having a high vapor pressure as a single body or an element capable of readily segregating on the surface. An Fe-Sb- based metal compound forms Fe-Sb molten liquid equilibrated with FeSb2 in an Sb-excess region within 628-728°C temperature region. The temperature region is the one in which the FeSi2 is stable as β-phase, and β-FeSi2 can be grown on an Si substrate. For example, a silicon substrate and an iron-antimony compound are fed to a semi-closed tube container held in a vacuum vessel, and kept at 680°C to provide the iron silicide. The iron-silicide phase formed by the heat treatment for 12 hr has only β-FeSi2 phase. A large-scale high- quality silicide bulk crystal can be grown by reacting the silicon substrate with the molten liquid, and the method is suitable for producing a high- performance electrothermal device.