Studies on the structure and properties of semiconductor ceramic cooling materials

Abstract

Thermoelectric polycrystalline ceramic materials were prepared by a new ceramic technology. Samples of p-type 72% Sb₂Te₃ + 25% Bi₂Te₃ + 3% Sb₂Se₃ doped with tellurium and 90% Bi₂Te₃ + 5% Sb₂Te₃ + 5% Sb₂Se₃ doped with Sbl₃ or Agl were studied. The new ceramic cooling materials have an inhomogeneous structure, but higher mechanical strength and thermoelectric properties. The method is simpler than the Bridgman and powder metallurgy processes. Measurements of properties show that sintering temperature and time effect the thermoelectric properties of the samples. Scanning electron microscopy shows that the polycrystalline ceramic materials have an obvious layered structure. The doping of the materials was studied, including doping variety and doping concentration. The figure of merit for n-type doped with Sbl₃ is 2.9 × 10⁻³ K⁻¹, while that for p-type doped with tellurium is 3.1 × 10⁻¹ K⁻¹.