Hydrogen bonding in hydrogenated amorphous silicon thin films prepared at different precursor gas temperatures with undiluted silane

Abstract

Hydrogen bonding configurations and hydrogen content in hydrogenated amorphous silicon (a-Si:H) thin films prepared at different precursor gas temperatures with undiluted silane have been investigated by means of Fourier transform infrared (FTIR) spectroscopy. The results show that the gas temperature before precursor gases entering the glow-discharge zone remarkably influences the hydrogen bonding configurations and the hydrogen content in a-Si:H thin films. The hydrogen content decreases from 18% down to 11% when increasing the gas temperature from room temperature (RT) to 433 K. Meanwhile, the clustered hydrogen at the physical film surface or at the internal surfaces of the microvoids decreases, indicating that a-Si:H thin films are densified at higher precursor gas temperatures. For a-Si:H thin films deposited at gas temperature of 433 K, the isolated silicon-hydrogen bonding configuration is predominant in the testing films. a-Si:H thin film, gas temperature, hydrogen bonding, FTIR, PECVD Citation: Wu M Y, Li W, Qiu Y J, et al. Hydrogen bonding in hydrogenated amorphous silicon thin films prepared at different precursor gas temperatures with undiluted silane.