采用射频等离子体增强化学气相沉积的方法, 研究制备了一种基于硅基薄膜的高反射一维光子晶体。通过交替改变反应气体组分实现低折射率SiOx层和高折射率a-Si层的交替层叠沉积, 具有两种膜层介质折射率比大、反射率高、沉积时间短、工艺窗口宽等优点。采用5周期的SiOx层与a-Si层构成的一维光子晶体(厚度分别为155 nm和55 nm), 其禁带范围内(650~1 100 nm)的平均反射率达到99.1%, 高于相同波长范围内Ag的平均反射率(96.3%)。

Highly reflective one dimensional photonic crystal (1D PC) based on silicon thin films was investigated and prepared using the radio frequency plasma enhanced chemical vapor deposition method. Both the low refractive index layer of SiOx and high refractive index layer of a-Si were deposited in the same chamber by alternatively changing the reaction gas component. The 1D PC has the advantage of high refractive index contrast, wide band gap, short depostion time and wide process window, which is a good candidate for the replacement of traditional high-reflection metal films. An average reflectivity of 99.1% was obtained within the bandgap (wavelength range of 650-1 100 nm) for an 1D PC constructed with only 5 periods of SiOx and a-Si, which is significantly higher than the Ag film of 96.3%.