電漿前後處理對射頻電漿輔助化學氣相沉積法沉積類鑽碳膜之影響

The effects of plasma pre-treatment and post-treatment on the diamond-like carbon films synthesized by RF plasma enhanced chemical vapor deposition

吳英傑(Ying-Jie Wu)

指導教授 ： 曾信雄

大同大學/工程學院/材料工程學系所/碩士(2007年)

摘要

本實驗以電漿輔助化學氣相沉積系統沉積類鑽碳膜，觀察氫氣及氬氣電漿在沉積碳膜前後及沉積過程中轟擊試片表面對碳膜結構與機械性質之影響。在沉積碳膜前電漿前處理實驗方面，主要以改變電漿前處理時之氬氣壓力及氫氣電漿功率來改變基材之表面粗糙度，之後以相同電漿條件沉積碳膜；在沉積碳膜過程中摻雜氫氣與氬氣之實驗方面，主要在沉積過程中改變乙炔對氬氣及乙炔對氫氣之流量比沉積碳膜；在沉積碳膜後電漿後處理實驗方面，則以改變氬氣電漿與氫氣電漿於碳膜表面之轟擊時間及不同比例氬氣與氫氣之混合電漿於碳膜表面之轟擊。經由各種處理之類鑽碳膜將測量其碳膜沉積速率、表面粗糙度、奈米硬度、楊氏模數、拉曼結構、殘留應力及奈米磨耗深度。
實驗結果顯示，經由不同條件電漿前處理之基板其表面粗糙度會有所變化且基板粗糙度對所沉積之碳膜粗糙度有一定的影響，但對於碳膜之硬度、楊氏模數、拉曼結構及殘留應力之影響則不明顯。在沉積碳膜過程中加入氫氣與氬氣電漿之實驗顯示，隨著氫氣與氬氣流量比的增加其碳膜表面粗糙度下降、硬度下降、楊氏模數下降及sp2結構比例增加，其中沉積過程中加入氫氣電漿對碳膜之殘留應力及磨耗深度也有所影響。在沉積碳膜後經氬氣與氫氣電漿後處理之類鑽碳膜，隨著後處理之時間增長碳膜表面粗糙度下降、硬度、楊氏模數下降且會改變碳膜之磨耗特性，在殘留應力上則無明顯之影響。

關鍵字

類鑽碳膜 ； 前處理 ； 後處理 ； 電漿輔助化學氣相沉積 ； 氬氣 ； 氫氣

並列摘要

Diamond-like carbon (DLC) films were deposited by RF plasma enhanced chemical vapor deposition and the effects of pre-treatment and post-treatment of H2 or Ar plasma and the effects of C2H2/H2 and C2H2/Ar ratios on the structure and properties of DLC films were investigated. In the plasma pre-treatment, Ar plasma of different pressures and H2 plasma of different RF powers were used to modify the surface roughness of substrate. For the plasma post-treatment, the effects of post-treatment time and Ar/H2 ratio were studied. Deposition rate, surface roughness, nanohardness, young’s modulus, Raman analysis, residual stress and nano-wear depth of DLC films after various treatments were measured.
Surface roughness characterized by AFM showed that plasma pre-treatment modified the substrate surface roughness, which will affect the roughness of the DLC films. However, the structure, hardness and residual stress of DLC films were not influenced by the plasma pre-treatment. For the DLC films deposited using different C2H2/Ar or C2H2/H2 ratios, it was found that as the C2H2/Ar or C2H2/H2 ratio was reduced, surface roughness, hardness and sp3/sp2 ratio decreased, and that the residual stress and the wear depth of the DLC films were also influenced by the C2H2/H2 ratio. For the Ar or H2 plasma post-treatment, surface roughness decreased with increasing treatment time. Hardness and the wear characteristics were also modified by the plasma post-treatment. However, the residual stress was independent of the Ar or H2 plasma post-treatment.

並列關鍵字

DLC ； pre-treatment ； post-treatment ； PECVD ； Argon ； hydrogen

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