Abstract Diamond/SiC interlayer with intermediate thermal expansion coefficient is introduced for improving the adhesion of NCD films on Ti substrate. Herein, tetramethylsilane (TMS) gas is added to produce SiC phase, forming a diamond/SiC interlayer. The effect of TMS gas flow on the microstructural evolution of the interfacial layer and the film adhesion is systematically investigated. At TMS gas flow of 5 sccm, the NCD film shows an interlayer of about 15% SiC by phase area statistics in SEM image. This film exhibits the lowest residual compressive stress of 1.64 GPa and the optimum adhesion of about 28.2 ± 2 N against Ti substrate. Increasing TMS gas flow leads to the increase of SiC content and the grain refinement of diamond in the interlayers. It is found that Ti silicide and hydride with increased amount are formed in the Ti substrate at higher TMS gas flow. The presence of these Ti intermetallic compounds with larger thermal expansion coefficient results in the increased residual stress and poorer adhesion in the NCD films. On the basis of reduction of Ti intermetallic compounds, the addition of TMS gas flow at 5 sccm is crucial for the preparation of good-adhesion NCD films on Ti substrate.

中文翻译：

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通过金刚石/碳化硅复合夹层在钛基底上沉积高粘性纳米晶金刚石薄膜

摘要 引入具有中等热膨胀系数的金刚石/碳化硅夹层以提高NCD薄膜在Ti衬底上的附着力。在此，加入四甲基硅烷 (TMS) 气体以产生 SiC 相，形成金刚石/SiC 夹层。系统地研究了 TMS 气流对界面层微观结构演变和膜粘附的影响。在 TMS 气流为 5 sccm 时，NCD 膜在 SEM 图像中通过相面积统计显示出约 15% SiC 的夹层。该薄膜表现出 1.64 GPa 的最低残余压应力和对 Ti 基材约 28.2 ± 2 N 的最佳附着力。增加 TMS 气体流量导致中间层中 SiC 含量的增加和金刚石的晶粒细化。发现在较高的TMS气体流量下，Ti基体中形成了数量增加的Ti硅化物和氢化物。这些具有较大热膨胀系数的 Ti 金属间化合物的存在导致 NCD 膜中残余应力的增加和较差的附着力。在还原 Ti 金属间化合物的基础上，加入 5 sccm 的 TMS 气流对于在 Ti 衬底上制备粘附性好的 NCD 薄膜至关重要。