化学气相沉积法制备金刚石膜截面微区Raman分析

采用微区Raman散射分析方法研究化学气相沉积法制备的金刚石膜的横截面.金刚石膜从衬底面到生长面不同位置具有不同特征的Raman谱，依此对膜中的金刚石、石墨和非晶碳成分进行分析.衬底面附近区域对应金刚石膜生长过程的成核阶段，非晶碳成分含量较高，相应于1200—1600cm^-1波段较大的散射强度和存在较强的荧光背底.膜厚增大，非晶碳成分中sp³结构成分首先减少，而sp²结构成分和石墨成分的减少相对缓慢.而生长面附近区域只有比较单纯的晶体金刚石 关键词：

VARIOUS HYSTERESIS LOOPS AND MULTISTABILITY ON OUTPUT CURVES OF TUNABLE EXTERNAL CAVITY SEMICONDUCTOR LASERS

Micro-Raman analyses were carried out to investigate the micro-structure of cross section for diamond films prepared by hot-filament chemical vapor deposition.The variation of Raman peak feature with position was recognized as the difference of micro-structure in the film.The presence of broad band and high background intensity near the substrate surface was attributed to the amorphous carbon synthesized in the nucleation process of diamond film.The reduction of sp³-bond structure in the amorphous carbon phase was used to account for the observation of the 1200—1600cm^-1 band intensity declination as the increase of film thickness.From the Raman feature it was shown that the sp²-bond structure and the graphitic phase decreased slowly,compared with the bond structure in the growth process of the film.The micro-Raman spectroscopy obtained by scanning parallel to the surface of the film showed the structure and composition difference between the diamond grain and the grain boundary.