High conductivity intrinsic a-SiGe films deposited at low-temperature

Abstract

Thin films of a-SiGe:H deposited by low-frequency plasma-enhanced chemical vapor deposition (LF PECVD) at 200 °C with improved conductivity are demonstrated. After thermal annealing at 500 °C, these films showed a-SiGe even better electrical conductivity than the obtained as PECVD deposited films. The annealing process to which the films were subjected was planned to enhance their transport properties while avoiding crystallization. After characterization by means of FTIR and Raman techniques, the solid phase of the thin film remained amorphous after annealing. The room-temperature electrical conductivity increased about three orders of magnitude from 2.27E-02 up to 2.47 S/cm for the non annealed to the annealed films. Because of the electrical and structural properties measured on the a-SiGe material here obtained, it is one of the best conductivity reached for intrinsic a-SiGe reported up to now. Its high electrical conductivity makes it suitable for its potential application in emerging and environment-friendly technologies such as flexible electronics, wearable electronics, and energy harvesting.