Semiconducting properties of several III B-V B-VI B ternary materials and their metallurgical aspects
The congruently melting compounds, Ga 6Sb 5Te and In 6Sb 5Te, and the peritectic compound, In 7SbTe 6 were found as a result of a study of the GaSb (or InSb)-GaTe (or InTe) pseudobinary phase diagrams. Zone melting was used to prepare polycrystalline samples of these compounds for electrical measurements. Here electrical conductivity, Hall effect, optical absorption, Seebeck coefficient and thermal conductivity data are reported. Possibility of the thermoelectric device, based on these compounds, is discussed. The energy gap of the forbidden band of Ga 6Sb 5Te ( Eg0=0·80 eV, Eg300=0·65 eV) is determined. Other related materials, which exist as intermediate phases of the pseudobinary systems InAs-InTe and In 2Te 3-Sb 2Te 3 (or Bi 2Te 3), are reported.