Silicon germanium oxide (Si_xGe_(1-x)O_y) infrared material for uncooled infrared detection

摘要

Thin film Si_xGe_(1-x)O_y infrared sensitive material was grown by RF magnetron sputtering, by depositing Si and Ge thin film simultaneously from two deposition targets in an oxygen (O) and argon environment at room temperature and at 400°C. Film composition was varied by adjusting RF power applied to the silicon target and by varying the oxygen flow of the gas mixture in the deposition chamber. The atomic compositions of Si, Ge, and O in the deposited thin film were determined and analyzed using energy dispersive X-ray spectroscopy (EDS). The influence of changing Ge and Si and O compositions on temperature coefficient of resistance (TCR), and resistivity were studied. Different fabrication scenarios have been used to vary the Ge, Si and O concentrations. The highest achieved TCRs and the corresponding resistivities at room temperature were -4.86 %/K and -6.43 %/K, and 2.45×10~2 Ω cm and 3.34×10~2 Ω cm using Si_(0.195)Ge_(0.706)O_(0.099)and Si_(0.127)Ge_(0.835)O_(0.038) for films deposited at room temperature and at 400 °C, respectively.