Patent ID: 6274802
Filing Date: 2001-08-14
Classification: H01L

Abstract:
A method of manufacturing a thermoelectric semiconductor material comprising:a heating step in which material powder is mixed so as to have a desired composition, and melted by heating;a solidification step, in which a solid solution ingot of thermoelectric semiconductor material having a rhombohedral structure is formed;a crushing step in which the solid solution ingot is crushed to form a solid solution powder;a screening step in which the grain size of the solid solution powder is made uniform;a sintering step in which the solid solution powder whose grain size has been made uniform is subjected to pressing and sintering; anda hot upset forging step in which hot upset forging is performed by subjecting the powder sintered body to plastic deformation while hot, and extending it, so that the crystal grains or subcrystal grains constituting the crystal grains of the powder sintered structure are aligned in a crystal orientation of excellent figure of merit for providing a thermoelectric material of satisfactory strength and performance, and the density ratio of the powder sintered body is finally at least 97%.