本研究使用微波電漿化學氣相沉積法成長之奈米鑽石膜應用於射頻微機電電容型開關，此開關最大可靠度問題為充電現象，在不斷的操作下開關容易引起下拉電壓偏移或沾黏現象，我們利用奈米鑽石膜當作此開關之介電層來改善電容型開關之充電現象，透過改變成長鑽石的製程參數來控制奈米鑽石膜中的石墨相比例，達到降低奈米鑽石之直流電阻值，使介電層內之充電電荷能夠快速的排出，進而增加開關之可靠度，我們藉由拉曼光譜、SEM、AFM等儀器對奈米鑽石做材料分析，期望找到最適合電容型開關使用之奈米鑽石膜，並使用MIM電容結構對奈米鑽石與傳統介電質氮化矽做直流量測、充放電量測等電性分析，證實奈米鑽石確實有我們希望得到電性。
我們設計出四種不同結構之電容型開關並使用C-V量測分析四種結構的下拉電壓大小與電容比等特性，另外針對使用氮化矽和奈米鑽石作為介電層時開關時的驅動特性與充電現象進行探討。

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.

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