微波電漿化學氣相沉積系統電場模擬分析與鑽石薄膜成長關係

A study of the relationship between diamond film synthesis and electric field of MPCVD using simulation approach

陳彥廷(Yen-Ting Chen)

指導教授 ： 林啟瑞 ； 蘇春熺

國立臺北科技大學/機電學院/製造科技研究所/碩士(2007年)

摘要

本研究在以模擬MPCVD系統改變三軸調節器、工作距離所產生不同電場強度分佈情況，並根據模擬分析結果比對實際類鑽碳膜沉積。固定功率800 Watt、工作壓力45 Torr、甲烷與氫氣之濃度比例0.25%，於(100)矽基材上進行鑽石薄膜的合成。成長機制先通入高濃度甲烷與氫氣之濃度比例1%用以成核10分鐘，再以甲烷與氫氣之濃度比例0.25%成長2小時。
研究指出利用Z軸調節器改變共振位置之結果，令試片座上兩端產生兩個共振位置，使得原先單一且體積較小的電漿球變為由兩個電漿球組成之大電漿球，用以增加鍍膜面積。但鍍膜時間由原先2~3小時(單電漿沉積)增加為5~6小時(雙電漿沉積)。隨著工作距離改變，試片座表面電場強度會遞增。將此結果與實際鍍膜比對，隨著工作距離變小鑽石品質變差，表示電場強度過大會造成類鑽碳膜沉積品質下降。

關鍵字

電場模擬 ； 微波化學氣相沉積系統 ； 類鑽碳膜

並列摘要

This research is based on microwave plasma CVD deposition to adjust different resonance cavities by using tuner. In order to find the opposable position between substrate and the center of plasma, we fixed the power at 800 Watt and the working pressure at 45 Torr. Also, the density ration between CH4 and H2 is 0.25% to grow diamond film on Si(100). Growing mechanism is first to lead-in high normality of CH4 and H2 mixing gas 1% to process nucleation for 10 minutes. Then using the mixing gas of CH4 and H2 which has the normality ratio of 0.25% to grow diamond film for 2-3 hours.
Using Z-axis tuner to change the result of resonance position is to produce two resonances positions which enables to separate one huge plasma ball into two smaller ones. This result is able to increase the deposition area; however, the deposition time is increasingly to 5-6 hour from the very beginning which is about 2-3 hours.
Based on the simulation result, changing the working distance doesn’t effect the electric field intensity. As the changing of working distance, the surface electric field intensity is increasing little by little. Meanwhile, as the working distance moving downwards, the quality of diamond is getting worse. This means when the electric intensity is getting lager, the quality of diamond film will decrease.

並列關鍵字

electric field simulation ； MPCVD ； diamond film

參考文獻

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