Simultaneous stoichiometric composition and highly (00l) orientation of flexible Bi2Te3thin films via optimising the DC magnetron sputter-deposition process

Abstract

Simultaneous stoichiometric composition and highly (00l) orientation of flexible Bi2Te3 thin films were investigated under the DC magnetron sputtering parameters. Stoichiometric Bi2Te3 and highly (00l) orientation structure was obtained by sputtering conditions, preheat temperature at 350 °C, and working pressure of 1.8 × 10−3 mbar. This designed structure of layered compact feature with stoichiometry provide the relatively high mobility. The maximum carrier mobility of 118 cm2/V was observed for highly (00l) film. The electrical conductivity of thin film has been greatly enhanced, to a maximum of about 14.90 × 103 S/cm at 50 °C. This value is higher than those of hot-pressed or spark plasma sintering n-type Bi2Te3 bulk alloys. The maximum power factor of 12.5 × 10−3 W/m.K2 was obtained at 300 °C.