Characterization of Sputtered Ge Film

Abstract

ABSTRACTThe electrical resistivity and microstructure of sputtered germanium film were characterized as a function of anneal temperature from 400 to 700°C. The as-deposited sputtered Ge film had an amorphous structure with resistivity of 165 Ω-cm which was maintained after annealing up to 540°C. After annealing above 550°C, the resistivity dropped by almost four orders of magnitude to ∼0.027 Ω-cm. The sharp transition of resistivity at 550°C is believed to be due to the recrystallization of Ge film from the as-deposited amorphous structure. The ohmic contact property on Ge films was also evaluated using sputtered tungsten. Low resistance ohmic contacts were obtained both on as-deposited and annealed Ge films, with typical ohmic contact resistance of 0.05 ± 0.008 Ω-mm on annealed Ge films. The W contacts were thermally stable after annealing up to 650°C.