PECVD工艺参数对SiO_2薄膜光学性能的影响

为探索利用等离子体增强化学气相沉积(Plasma Enhanced Chemical Vapor Depo-sition,PECVD)技术制作光学薄膜的有效方法.以SiH4和N2O作为反应气体,通过采用M-2000UI型宽光谱变角度椭圆偏振仪对制作样片进行测试,分析了薄膜沉积过程中的不同的工艺参数对SiO2薄膜光学性能的影响.实验结果表明:在PECVD技术工作参数范围内,基底温度为350℃,射频功率为150 W,反应气压为100 Pa时,能够沉积消光系数小于10-5,沉积速率为(15±1)nm/min,折射率为(1.465±0.5)×10-4的SiO2薄膜.

Optical Properties of SiO_2 Thin Films Prepared by PECVD

To explore a feasible method to prepare optical thin films by plasma enhanced chemical vapor deposition（PECVD） technology, using SiH4 and N2O as reacting gas, SiO2 thin film was successfully prepared on silicon substrate by PECVD. Optical properties of the films were examined by M-2000UI variable angle incidence spectroscopic ellipsometer. The results show that SiO2 thin film with extinction coefficient less than 10-5 can be deposited at the deposition rate of （15±1） nrn/min under the condition of substrate temperature 350℃, RF power 150 W and reaction pressure 100 Pa ,in addition the refractive index of the film（n equals about 1. 465） can be controlled accurately.