基于玻璃碳基底的超薄自支撑多晶金刚石膜制备

Preparation and growth mechanism of ultra-thin free-standing polycrystalline diamond film based on glass carbon substrate

选取Ti、Si、玻璃碳3种基底,采用微波等离子体化学气相沉积技术,以CH_(4)/H_(2)为反应源制备超薄多晶金刚石膜。通过SEM、Raman、台阶仪表征并分析所制备的金刚石薄膜整体形态、表面(断面)形貌、组成、应力状态等。结果表明:仅以玻璃碳为基体生长的金刚石膜能自动剥离形成完整自支撑体,且薄膜表面晶粒的晶面显形清晰,膜厚仅为10μm;Raman光谱表征表明薄膜呈强的尖锐金刚石特征峰,且计算的残余应力最低,仅有−0.2161 GPa。可为超薄自支撑CVD金刚石膜的一步法生长-剥离提供新的技术途径。

In these experiments,Ti,Si and glass carbon substrates were selected to prepare ultra-thin polycrystalline diamond films by microwave plasma chemical vapor deposition(MPCVD)using CH_(4)/H_(2) as the reaction source.The overall morphology,surface morphology,composition and stress state of the prepared diamond films were characterized and analyzed by SEM,Raman and a profilometer.The results show that only diamond films grown on glass carbon substrate can be automatically peeled off to form a complete free-standing film.The crystal surface of the film grains is clear,and the film thickness is only 10μm.Raman spectra reveal that thin films have strong sharp diamond characteristic peaks,and that the calculated residual stress is the lowest,which is−0.2161 GPa.It is expected to provide an effective new technique for the one-step growth and stripping of ultra-thin self-supported CVD diamond films.