本文简单介绍反应离子刻蚀的基本原理和激光干涉在线监控刻蚀的原理,比较了两种不同的反应气体(CF_4、SF_6)系统中polycide膜的刻蚀速率和多晶硅与二氧化硅的刻蚀速率比,实验表明SF_6气体有较大的刻蚀速率和较高的选择性,是刻蚀polycide合适的反应气体. In this paper, the basic principles of reactive ion etching and the principle of laser interference on-line monitoring etching are introduced briefly. The etching rates of polycide films and polysilicon and silicon dioxide in two different reaction gases (CF 4, SF 6) are compared The experimental results show that the SF6 gas has larger etching rate and higher selectivity and is suitable for etching polycide gas.