Preparation, Phase-Boundary Energies, and Thermoelectric Properties of InSb-Sb Eutectic Alloys with Ordered Microstructures

Abstract

Two‐phase solids, single‐crystal rods of Sb in a matrix of single‐crystal InSb, have been prepared by eutectic crystallization. The size of the Sb rods decreases with increasing crystallization velocity, in quantitative agreement with the theory of eutectic crystallization. The boundary energy between the InSb and the Sb phases was determined both from the parameters of the crystallization and from a dislocation model. Both values agree, indicating that the strain energy of the dislocations at the phase boundary is the chief contributor to the interfacial energy. The electrical resistivity ρ, the thermoelectric power Q, and the thermal conductivity K have been measured as a function of the structural arrangement of the two phases in the alloys. The magnitudes of ρ and Q have been explained by simple electrical analogs of the eutectic structure. A characteristic decrease of the thermal conductivity of the eutectic alloys has been observed. The reduction in K is probably caused by interaction of phonons with the phase boundaries.