Microwave Plasma CVD Nanodiamond and Its Application to RF MEMS Capacitive Switches

• Main Authors: Chang-WeiChen, 陳昶瑋
• Other Authors: Yon-Hua Tzeng
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/02237981579789795565

碩士 === 國立成功大學 === 微電子工程研究所碩博士班 === 98 === In this research, we deposit nanodiamond films by Microwave Plasma Chemical Vapor Deposition. Nanodiamond used as dielectric layer of RF MEMS capacitive switches. The major problem need to be solved is charging effect, and it also limit the life time of switches. After operation many times, switches would induce pull-in voltage shift and stiction problem. We use nanodiamond films as dielectric material to prevent the charging effect of switches. We controlled graphite phase concentration of nanodiamond films by using different growth conditions to lower dc resistivity. It can allow charges to escape from dielectric layers quickly and increase the reliability of switches. In order to find the best growth condition of nanodiamond films for switches, we analyzed nanodiamond films by some equipment, including Raman spectrum, Scanning Electron Microscope and Atomic Force Microscope..We fabricated MIM capacitors by Si3N4 and nanodiamond to perform DC measurement and transient current measurements. We designed four structures of RF MEMS capacitive switches and analyzed their pull-in voltage and capacitance ratio by C-V measurement. Additionally, we discussed about actuation properties and charging effect of switches with Si3N4 and nanodiamond as dielectric, respectively.