衬底温度对氢离子束辅助磁控溅射制备a-Si∶H薄膜结构特性的影响

Effect of Substrate Temperature on Microstructures and Optical Properties of a-Si∶H Coatings Grown by Ion Beam Assisted Sputtering

利用氢离子束辅助磁控溅射制备氢化非晶硅薄膜(a-Si∶H),借助拉曼光谱仪、红外光谱仪和椭圆偏振光谱仪等分析测试手段,研究衬底温度对a-Si∶H薄膜结构特性影响规律。结果表明在合适的衬底温度下氢离子束辅助磁控溅射制备的a-Si∶H薄膜具有较好短程有序度和中程有序度;当衬底温度为200℃时,薄膜的结构特性最优,a-Si∶H薄膜的次带吸收系数为0.46 cm^(-1)、氢含量为10.36%(原子比)、微结构因子为0.68和光学带隙为1.94 e V。

The hydrogenated amorphous silicon （a-Si： H ）thin films were synthesized by ion-beam-assisted sputtering on substrates of quartz and Si wafer. The effect of the growth conditions, including but not limited to the substrate temperature, RF power and ratio of argon/hydrogen flow rates, on the microstructures and optical behavior of the a-Si： H coatings was investigated with Raman spectroscopy, Fourier transform infrared （FTIR） spectroscopy, and spectroscopic ellipsometry. The results show that the substrate temperature significantly affects the microstructures and optical properties of the a-Si ： H films. To be specific, deposited at anoptimized substrate temperature （200℃） ,the a-Si： H coatings, with higher short-range （nearestneighbor）and intermedium-range （beyond nearest- neighbor） orders, displayed an atomic hydrogen content of 10.36% （at.）, an sub-bandgap absorption coefficient of 0. 46 cm - 1 at 0. 8 eV, an optical gap of 1.94 eV and a microstrueture factor of 0.68.