Structure and mechanical properties of low stress tetrahedral amorphous carbon films prepared by pulsed laser deposition
Structure and mechanical properties of low stress tetrahedral amorphous carbon films prepared by pulsed laser deposition
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脉冲激光沉积制备低应力四面体非晶碳薄膜的结构与力学性能
DOI：
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发表时间：
2002
期刊：
影响因子：
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通讯作者：
P. Ossi
中科院分区：
文献类型：
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作者：
M. Bonelli;A. Ferrari;A. Fioravanti;A. Bassi;A. Miotello;P. Ossi
翻译后摘要：四面体非晶碳膜已产生的脉冲激光沉积，在248 nm的波长，烧蚀高度取向的热解石墨在室温下，在10-2 Pa的真空，在0. 5和35 Jcm-2之间的能量密度。使用（100）Si晶片和覆盖有SiC多晶中间层的晶片两者作为衬底。通过拉曼光谱和透射电子能量损失谱研究了薄膜的结构。的薄膜，这是无氢，如所示的傅里叶变换红外光谱，经历了从主要是无序石墨高达80%四面体无定形碳（ta-C）的阈值激光能量密度为5 J cm-2以上的过渡。通过X射线反射率粗糙度，密度和横截面分层选定的样品进行了研究。通过纳米压痕在沉积有SiC中间层的膜上获得高达70 GPa的膜硬度。通过划痕试验，测得膜的粘附力和摩擦系数在0.06和0.11之间。通过轮廓术，我们得到的残余应力值不高于2 GPa的80%的sp3 ta-C膜沉积。
Abstract:Tetrahedral amorphous carbon films have been produced by pulsed laser deposition, at a wavelength of 248 nm, ablating highly oriented pyrolytic graphite at room temperature, in a 10-2 Pa vacuum, at fluences ranging between 0.5 and 35 Jcm-2. Both (100) Si wafers and wafers covered with a SiC polycrystalline interlayer were used as substrates. Film structure was investigated by Raman spectroscopy at different excitation wavelength from 633 nm to 229 nm and by transmission Electron Energy Loss Spectroscopy. The films, which are hydrogen-free, as shown by Fourier Transform Infrared Spectroscopy, undergo a transition from mainly disordered graphitic to up to 80% tetrahedral amorphous carbon (ta-C) above a threshold laser fluence of 5 J cm-2. By X-ray reflectivity roughness, density and cross-sectional layering of selected samples were studied. Film hardness as high as 70 GPa was obtained by nanoindentation on films deposited with the SiC interlayer. By scratch test film adhesion and friction coefficients between 0.06 and 0.11 were measured. By profilometry we obtained residual stress values not higher than 2 GPa in as-deposited 80% sp3 ta-C films.