【摘要】 涂石墨粉增强金刚石薄膜形核密度的研究张贵锋，耿东生，李兴无，郑修麟关键词ＣＶＤ（化学气相沉积），预涂层，石墨粉，金刚石膜中图分类号ＴＢ４３微电子学等领域的应用往往要求金刚石选择性生长；而作为耐磨硬质涂层，要求最大限度地提高形核密度，以便获得连续、均匀...更多还原

【Abstract】 Enhancing nucleation density of diamond film is of great importance to its applications in the microelectronics, optical, and mechanical industries. The nucleation density of diamond film can be enhanced by mechanical pretreatment of substrate surface, such as polishing and etching, and non-mechanical pretreatment, such as precoating Intermediate layer withdiamond -like carbon, C60 or C70, and nano-carbontube. Hgh nucleation density and high quality diamonds synthesized by precoating with graphite, however ) have, to the best of our knowledge, not been reported in the open literature. Diamond films are grown in a thermal CVD reactor. Typical deposition conditionS are: pressure of 20 Torr; filament and substrate temperature of 2000℃ and 750℃ respectively;filament-to-substrate distance of 8 mm ; and a gas composition of 1% methane in H2 at a typical now rate of 100 seem. A pretreatment of substrate surface includes dispersing graphite particles in alcohol, and then spreading solution on the substrate surface. The precoated Si substrates are treated in 10034 H2 gas for 0～30 min before introducing CH4 into the reactive system for glowing diamond films for 3 h. Figure 1 shows the morphology of the diamond film obtained by precoating with graphite particles. Fig. la corresponds to no pretreatment under 100% H2 gas; though the 0. 3μm ball-like diamond particles are well distributed and fine, they contain relatively more graphite and amorphous carbon than are desirable for good-quality diamond film. Fig. lb corresponds to pretreatment under 100% H2 gas; this treatment is needed for obtaining cubooctahedral facets of 2μm diamond crystals and letting good-quality diamond film form continuouly in a quite short time of only 4 h.The possible explanation for the enhancement in nucleation density is that hyd-ogen atoms etch graphite and then increase concentration of nueleation precursors of substrate surface.The experiments show that high-quality and high density diamond films depend on pretreating time in 100% H2 gas.更多还原