LCP基RF MEMS开关的工艺研究

Processing Study on LCP RF MEMS Switch

在柔性LCP基板上制备RF MEMS开关,加工难度较大,影响开关质量的因素较多。主要研究影响LCP基RF MEMS开关加工质量的主要因素,寻找工艺过程控制解决方案。通过对关键工序的试验,对加工过程中的基板清洗、LCP基板覆铜面镀涂及整平、LCP基板无铜面溅射金属膜层、LCP基板平整度保持、二氧化硅膜层生长及图形化、牺牲层加工、薄膜微桥加工、牺牲层释放等工序进行了参数优化。研制的LCP基RF MEMS开关样件频率≤20 GHz、插入损耗≤0.5 d B,回波损耗≤-20 d B,隔离度≥20 d B,驱动电压30~50 V。该加工方法对柔性基板上可动结构的制造具有一定的借鉴价值。

Due to the multi influences on quality of RF MEMS switch, it is difficult to fabricate the switch on flexible LCP substrate. Here, we present for the study on the key influence on LCP RF MEMS fabrication to find the processing solution. According to the experiment, the parameters of substrate cleaning, electro-plating and leveling on Cu lamination layer, metal film on LCP substrate without copper, flatness maintain during lithography, Si O2 film growing and patterning,fabrication of scarified layer forming, fabrication of thin film bridge and releasing of scarified layer were optimized. LCP RF MEMS switch with frequency less than 20 GHz was fabricated, whose insertion loss is no more than 0.5 d B, return loss is no more than-20 d B, isolation is no less than 20 d B, and driving voltage is 30 V to 50 V. The method mentioned here may have successful experiences on fabrication of moving parts on flexible substrate.