PDF(Pubmed)
Abstract：
Different nano-sized phases were synthesized using chemical vapor deposition (CVD) processes. The deposition took place on {001} Si substrates at about 1150-1160 °C. The carbon source was thermally decomposed acetone (CH3)2CO in a main gas flow of argon. We performed experiments at two ((CH3)2CO + Ar)/Ar) ratios and observed that two visually distinct types of layers were deposited after a one-hour deposition process. The first layer type, which appears more inhomogeneous, has areas of SiO2 (about 5% of the surface area substrates) beside shiny bright and rough paths, and its Raman spectrum corresponds to diamond-like carbon, was deposited at a (CH3)2CO+Ar)/Ar = 1/5 ratio. The second layer type, deposited at (CH3)2CO + Ar)/Ar = a 1/0 ratio, appears homogeneous and is very dark brown or black in color and its Raman spectrum pointed to defect-rich multilayered graphene. The performed structural studies reveal the presence of diamond and diamond polytypes and seldom SiC nanocrystals, as well as some non-continuously mixed SiC and graphene-like films. The performed molecular dynamics simulations show that there is no possibility of deposition of sp3-hybridized on sp2-hybridized carbon, but there are completely realistic possibilities of deposition of sp2- on sp2- and sp3- on sp3-hybridized carbon under different scenarios.
摘要：
使用化学气相沉积（CVD）工艺合成了不同的纳米尺寸相。在约1150-1160°C下在{001}Si衬底上进行沉积。碳源是在氩气主气流中热分解丙酮(CH3)2CO。我们在两个((CH3)2CO+Ar)/Ar)比率下进行了实验,并且观察到在一小时的沉积过程之后沉积了两种视觉上不同类型的层。第一层类型，看起来更不均匀，有SiO2区域（约5％的表面面积的基板）旁边有闪亮的明亮和粗糙的路径，它的拉曼光谱对应于类金刚石碳，以(CH3)2CO+Ar)/Ar=1/5的比例沉积。第二层类型，在(CH3)2CO+Ar)/Ar=1/0比例下沉积，呈现均匀且颜色非常深棕色或黑色,其拉曼光谱指向富含缺陷的多层石墨烯。进行的结构研究揭示了金刚石和金刚石多型体的存在，很少有SiC纳米晶体，以及一些非连续混合的SiC和类石墨烯薄膜。进行的分子动力学模拟表明，没有可能在sp2杂化的碳上沉积sp3杂化，但是在不同的情况下，sp2-在sp2-和sp3-杂化碳上沉积sp3-存在完全现实的可能性。
