High performance co-sputtered Bi2Te3 thin films with preferred orientation induced by MgO substrates

- Preparation of highly (00l)-oriented Bi2Te3 thin films induced by single crystal MgO substrates using sputtering.
- Preferred orientation is conductive to carrier transport and increases the Seebeck coefficient.
- The abundant Te introduced much more interfaces and boundaries.
- The Seebeck coefficient and power factor of bismuth telluride films were improved.

Bi2Te3 thin films were fabricated on the (00l)-oriented MgO substrates by the magnetron co-sputtering method. The films microstructure of highly preferred orientation along the c-axis had been obtained through the inducing of single crystal MgO substrates. And some abundant Te was introduced into the Bi2Te3 films through sputtering tellurium target, which affected the scattering process. The (00l) preferred orientation is beneficial to the carriers transport. In this case, the higher performance of Bi2Te3 thin films can be obtained. And microstructure and thermoelectric properties of Bi2Te3 thin films were investigated systematically.