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

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.