一种基于光刻胶牺牲层的RF MEMS开关制备方法

A Method for Preparing RF MEMS Switch Based on Photoresist Sacrificial Layer

论文针对RF MEMS开关上电极传统的牺牲层工艺存在工艺兼容性差、释放时热应力大等问题,提出了一种基于光刻胶牺牲层的MEMS开关制备方法。通过采用在氮气环境下进行固化处理的方法,解决了光刻胶作为牺牲层时容易出现的表面褶皱、破裂等问题,同时提高了牺牲层表面的平整度;通过氧等离子体干法刻蚀释放工艺,获得了具有高平整度和低粗糙度的MEMS开关上电极结构。测试结果表明,基于光刻胶牺牲层工艺制备的RF MEMS开关在DC-20GHz频段内性能良好,隔离度均小于-30.0dB,插入损耗均大于-1.0dB。该RF MEMS开关具有良好的应用前景。

To solve the problems of poor process compatibility and high thermal stress during the release in the conventional sacrificial layer process for the upper electrode of RF MEMS switches,this paper proposes a method for preparing MEMS switches based on photoresist sacrificial layers.By using the curing method under nitrogen,the surface wrinkling and cracking problems that tend to occur when the photoresist is used as a sacrificial layer are solved,and the flatness of the surface of the sacrificial layer is im⁃proved.The upper electrode structure of MEMS switch with high flatness and low roughness is obtained by oxygen plasma dry etch⁃ing and release process.The test results show that the RF MEMS switches prepared based on the photoresist sacrificial layer process have good performance in the DC~20GHz band,with the isolation degree less than-30.0dB and the insertion loss greater than-1.0dB.This RF MEMS switch has good application prospects.