Effects of Process Variable Control on the Thermoelectric Properties of the Zn_(0.98)Ga(Al)_(0.02)O System

摘要

The main factors influencing the different solubility limits of Al- and Ga-doped ZnO systems are studied. The different thermoelectric properties of Al- and Ga-doped ZnO systems were attributed in prior studies to the different solubility limits and secondary phases of these systems. In this study, the origin of these differences, i.e., the Ga_2O_3(ZnO)_9 secondary phase, was suppressed by a low-temperature synthesis process for the Zn_(0.98)Ga_(0.02)O solid solution. As a result, a novel synthesis process for Zn_(0.98)Ga_(0.02)O solid solution without the Ga_2O_3(ZnO)_9 phase was established, and the thermoelectric properties with and without the Ga_2O_3(ZnO)_9 secondary phase were compared. The thermoelectric properties of Zn_(0.98)Al_(0.02)O and Zn_(0.98)Ga_(0.02)O specimens without Al_2O_3(ZnO)_9/Ga_2O_3(ZnO)_9 phases were also compared.