直流磁控溅射制备a-Si:H膜工艺及其在激光器腔面膜上的应用

利用直流(DC)磁控溅射方法制备氢化非晶硅(a-Si∶H)薄膜。研究了氢气流量、溅射源功率对膜的沉积速率、氢含量(CH)以及光学性能的影响。通过傅里叶变换红外(FTIR)吸收光谱计算氢含量,其最大原子数分数为11%。用椭偏仪测量了膜的折射率n和消光系数k,发现a-Si∶H薄膜的k值和n值都随CH的增加而减小。将优化的实验结果用于半导体激光器腔面高反镜的镀制,a-Si∶H薄膜在808 nm波长处的n和k分别为3.2和8×10-3,获得了良好的激光输出特性。

Process Investigation of a-Si:H Thin Films Prepared by Direct Current Magnetron Sputtering and Application on Diode Laser Cavity Coatings

Hydrogenated amorphous silicon (a-Si:H) thin films have been prepared by direct current (DC) magnetron sputtering. The effects of the hydrogen flow rate, sputtering power influencing on deposition rate and the optical characteristics of a-Si:H thin films have been investigated. The hydrogen content (CH) of the films is calculated by Fourier transform infrared (FTIR) spectroscopy method, and the maximum CH is obtained at 11% (atom percent). The refractive index (n) and extinction coefficient (k) are measured by spectroscopic ellipsometer. It is found that the n and k of the prepared film decrease with the increase of CH. The optimizing parameters are applied to the preparation of high reflection mirror of diode lasers, and the n and k at 808 nm wavelength are 3.2 and 8×10-3 respectively with a satisfactory laser output characteristics.