Effects of the hydrogen plasma treatment on the thin-film polycrystalline SiGe

We have investigated the hydrogen plasma treatment of thin-film polycrystalline SiGe with 65 % Ge content. The amorphous SiGe films were prepared at 200degC by a radio-frequency (RF) magnetron sputtering system and then crystallized by solid phase crystallization at 580degC. The hydrogen plasma treatment was done by an inductively-coupled RF plasma and RF bias voltage applied to the substrate. The dark conductivity and the absorption coefficients corresponding to energy gaps were decreased by the hydrogen plasma treatment. The best conditions were 300degC and 10 Pa-15 Pa with the proper RF bias voltage. The results suggest that the hydrogen plasma treatment is effective to reduce the dangling bond defects in the polycrystalline SiGe thin films