Effect of assisted-ion-beam gases on the structure of amorphous silicon thin films prepared by ion-beam-assisted sputtering

摘要

In this work, amorphous silicon (a-Si) thin films were prepared by ion-beam-assisted sputtering, the effect of assisted-ion-beam gases on the thin-film structure were investigated using Raman spectroscopy, Fourier transform infrared spectroscopy, and spectroscopic ellipsometry. It was observed that the introduction of assisted-ion beam improved the thin-film structure, and the ion-beam-assisted sputtering a-Si thin films possessed higher short-range order, intermediate-range order, lower microstructure parameter (R~*) and defect density of states with the increased of hydrogen concentration in the assisted-ion beam gases, which due to the transfer of energy from ion to the surface Si atoms and the formation of Si-H bonds in the a-Si thin films. The a-Si thin films deposited with hydrogen-ion beam possessed the absorption coefficient at 0.8 eV and microstructure factor of 0.7 cm~(-1) and 0.48. It was illumined that the device-quality a-Si thin films can be achieved under the ion-beam-assisted sputtering.