The influence of electric field on the microstructure of nc-Si:H films produced by RF magnetron sputtering

Abstract

Hydrogenated nanocrystalline silicon thin films were prepared by RF magnetron sputtering. Different bias fields (no bias–no ground, grounded and negative bias) were applied to the substrate. The effect of the ion bombardment on the structure, chemical composition and optical property were studied by Raman spectroscopy, X-ray diffraction, Rutherford backscattering (RBS) and optical transmission spectroscopy. The deposition rate and the optical bandgap decrease as the bias voltage increases from 0 to -50 V. The structural characterization indicates that compressive stress is developed in plane and tensile stress is induced in the growth direction. No significant variation on the chemical composition was observed.