類鑽碳薄膜DLC(diamond-like carbon film)具有堅硬、耐磨耗、抗腐蝕等優良的力學性質，亦能擁有同石墨般良好的導電、乾潤滑特性。性質的偏向與薄膜中碳與碳之間sp3及sp2鍵結含量的多寡習習相關，是評估DLC特性的重要指標。由於針對非晶材料微結構組成的分析設備有其極限，在原子尺度下數值模擬是另一可靠的研究工具，可以深入洞察DLC薄膜結構與其性能間的關係，並觀測DLC成膜過程中發生的各種現象。

本文利用分子動力學模擬C60團簇於矽(001)基板的成膜過程。探討高入射能量(5~20ev/atom)及入射角度變化(0°~45°)對薄膜內各種性能指標的影響。

研究顯示較低能量(5ev/atom)的團簇沉積容易受到入射角度影響，生成多孔且粗糙的薄膜，並有sp3含量下降的情況；然而較高能沉積(10ev/atom)的薄膜性質並不易受角度影響，且能同時兼備均質、高密度、高sp2含量等優點；然而當入射能量過高(15ev/atom)時，角度效應幾乎無法察覺，薄膜性質則因矽原子大量濺入而劣化，因為矽、碳會結合成碳化矽，阻礙DLC的成長。

Diamond-like carbon (DLC) films are composed of carbon bonds with different hybridizations, including sp2, sp3 and even sp. Understanding the atomic bonding structure is essential to understanding the properties and optimizing the process parameters of the films. Because of the limited analytical tools for characterizing the atomic bonding structure in amorphous materials, computational research at the atomistic scale could provide significant insight into the structure-property relationships in diamond-like carbon films and has been applied to understanding the various phenomena occurring during DLC film growth.

The influence of incident energy(5~20ev/atom) and incident angles(0°~45°) of energetic C60 clusters on the structure and properties of DLC films on silicon(001) substrate was investigated by the molecular dynamics simulation using a Tersoff interatomic potential.

The present simulation revealed that when the incident energy was relatively low (5ev/atom), as the incident angles increased, the surface roughness of DLC films increased and the more porous structure was generated, and therefore decreased the amount of sp3 but increase sp2. However, properties of films grown by higher energy deposition (10ev/atom) is not susceptible to the variations in incident angle, and could at the same time maintain homogeneous, high-density, and high-sp2 content structure. The effect of incident angle was almost imperceptible to the properties of film while the incident energy exceeded 15ev/atom, because impact of high energy clusters would sputter silicon atoms into to the film. Thus it deteriorated the film due to the formation of silicon carbide, which would hinder the growth of DLC.

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