本研究將以非平衡磁控濺鍍法在矽晶圓上沉積含氫非晶質碳膜，各別將甲烷與乙炔以不同通量混入固定通量(25 sccm)的氬氣，以直流電源激發氣體產生電漿，沉積時間固定為120分鐘。在濺鍍製程中，同時以光學放射光譜儀(OES)透過真空腔體窗口記錄電漿內激發物種的種類與強度。以拉曼光譜儀(Raman)與傅立葉轉換紅外光譜儀(FTIR)來量測含氫非晶質碳膜表面的結構並作定性分析。以奈米壓痕機量測碳膜的硬度、楊氏係數、抵抗側向刮痕的能力與表面的摩擦係數。掃瞄式電子顯微鏡量測膜厚與觀察表面形貌；高阻抗電阻儀量測碳膜電阻值。由OES光譜可知，Hα與Hβ的強度在甲烷/氬氣電漿隨流量變化程度比乙炔/氬氣電漿大，從流量增加來觀察激發物種強度變化，Hα與Hβ比CH*與C2*更容易受到電漿激發。隨流量增加單位氣體分子獲得能量降低，推測甲烷主要解離成CH3而乙炔主要解離成C2H。從Raman與FTIR光譜結果得知，當甲烷或乙炔流量增加，碳膜表面的sp3 CH3與sp3 CH2鍵結增加，使碳膜的sp3/ sp2比增加，此外sp2結構將從苯環狀碳環轉變成烯烴碳鏈；乙炔碳膜的sp3/ sp2比增加幅度比甲烷碳膜小，因為甲烷直接解離成CH3即可形成sp3 C-H結構，但乙炔解離成C2H後需要再進一步反應才能形成sp3 C-H結構。氫在碳膜中阻擋碳碳原子間形成sp3 C-C並且形成sp3 C-H，造成碳膜硬度隨C-H鍵結增加而下降，10 sccm的甲烷碳膜與乙炔碳膜硬度降至2.75 GPa與5.86 GPa。由於C-H鍵結將鈍化碳膜表面，使甲烷與乙炔碳膜的摩擦係數隨著表面C-H結構增加而降低。由於碳膜的表面sp3 C-H鍵結增加與sp2結構從碳環轉變成碳鏈，導致甲烷碳膜電阻值隨流量而劇烈增加而乙炔碳膜電阻值則隨流量而緩和增加。由激發氣態物種觀察與碳膜性質比對，沉積後的碳膜機械性質主要是受到表面形成的sp3 C-H結構影響，sp3 C-H結構的形成則與甲烷/氬氣和乙炔/氬氣電漿的解離效率有密切關聯。

Hydrogenated Amorphous Carbon (a-C:H) films was deposited on the silicon substrate by unbalanced magnetron sputtering with the addition of methane (CH4) or acetylene (C2H2) and the variation of flowing rates from 2 to 10 sccm into argon plasma. The flowing rate of argon was constant at 25 sccm and the deposition time was fixed at 120 min. Optical Emission Spectrometer (OES) was employed in analyzing the excited species in methane or acetylene/argon plasma through a view port of the processing chamber. The quality of a-C:H films, including their chemical structure, nano-hardness, friction coefficient, and surface resistance, was examined. From OES spectra, the emission intensity of atomic hydrogen Hα and Hβ for methane/argon plasma was found higher than that for acetylene/argon plasma. In addition, by increasing the flowing rate of methane or acetylene, the intensity of Hα, Hβ, CH*, C2* significantly changed. The excitation of Hα and Hβ were relatively simple, in comparison with that of CH* and C2*. It is assumed that CH4 and C2H2 were firstly ionized into CH3 and C2H, respectively. From Raman and FTIR spectra, as increased the flowing rate of methane or acetylene, sp3 CH3 and sp3 CH2 structure increased on surface that caused sp3/sp2 ratio of a-C:H films increased; in addition, sp2 structure transformed from aromatic rings into olefinic chains. Owing to the varied lengths of pathway to ionize the hydrocarbon species, methane was more affected than acetylene by the formation of sp3 C-H on the a-C:H surface. Hydrogen in a-C:H films blocked carbon atoms to form the sp3 C-C (cross-linking) and formed sp3 C-H instead which caused nano-hardness of a-C:H films decreased with the increased flowing rate of methane or acetylene. Nano-hardness of a-C:H films decreased to 2.75 GPa and 5.86 GPa at the flowing rate 10 sccm of methane and acetylene. Due to sp3 C-H increased and sp2 structure transformed, the resistance of a-C:H films increased with the flowing rate of methane or acetylene. From the observations of the excited gaseous species and the quality of a-C:H films, the mechanical properties of a-C:H films were most probably affected by the formation of sp3 C-H structure, which was closely associated with the efficiency of ionization from methane/argon or acetylene/argon plasma.

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