热丝CVD法制备金刚石—碳化铬复合薄膜

发布时间：2018-02-27 22:53

本文关键词： 金刚石薄膜碳化铬复合中间层粘附性热丝CVD　出处：《大连理工大学》2010年硕士论文　论文类型：学位论文

【摘要】： 化学气相沉积(CVD)金刚石薄膜可以在多种基体上沉积,并且不受基体几何形状的限制,有广泛的应用前景。但是由于金刚石与基体的热膨胀系数的差异很大,在冷却过程中在金刚石薄膜与基体界面处的薄膜内产生很大的切应力,导致金刚石薄膜与基体的粘附性差,阻碍了CVD金刚石薄膜应用。本文实验采用CH4与H2的混合气体作为反应气源,镀铬钨丝作为铬源,用热丝化学气相沉积法制备金刚石—碳化铬复合薄膜,把热应力分布到复合中间层,减小基体界面处金刚石薄膜内的切应力,提高金刚石薄膜与基体的结合强度,从根本上改善金刚石薄膜与基底的粘附性。本文首先研究了蒸铬的条件,沉积了Cr薄膜。然后在生长金刚石的条件下沉积了碳化铬薄膜,XRD分析表明,铬的三种碳化物Cr3C2、Cr7C3与C23C6均有生成。实验中发现在氢气-甲烷气氛下,铬表层被碳化铬包覆不能连续蒸发,经过脱碳处理,可以实现间断蒸铬。通过对不同实验阶段的铬源的物相分析发现Cr3C2相的生成是导致铬源难以蒸发的主要原因。首次提出金刚石与碳化铬在空间上交替生长的方法：根据碳化铬与金刚石生长速度的差异实行短时间多次蒸铬,长时间多次生长金刚石,通过控制蒸铬量实现金刚石-碳化铬两相的交替生长,制备了金刚石-碳化铬复合薄膜,并在金刚石-碳化铬复合中间层上沉积了金刚石薄膜。用SEM、XRD对薄膜的表面形貌,物相进行了分析。本文在以下几个方面有创新：首次把固体铬引入热丝化学气相装置,仅利用热丝的热辐射使铬蒸发。据我们所知,这是首次用热丝CVD成功制备Cr薄膜、碳化铬薄膜和金刚石-碳化铬复合薄膜。
[Abstract]:Chemical vapor deposition (CVD) diamond films can be deposited on a variety of substrates, and are not limited by the geometrical shape of the substrates, so they have a wide application prospect. However, the thermal expansion coefficients of diamond and substrates vary greatly. During the cooling process, great shear stress occurs in the interface between diamond film and substrate, which leads to poor adhesion between diamond film and substrate. In this paper, the mixture gas of CH4 and H2 was used as the reaction gas source, the chromium-tungsten wire as the chromium source, and the hot-filament chemical vapor deposition method to prepare the diamond-chromium carbide composite film. The thermal stress is distributed to the composite interlayer to reduce the shear stress in the diamond film at the interface of the substrate, to improve the bonding strength between the diamond film and the substrate, and to improve the adhesion of the diamond film to the substrate. In this paper, the conditions of chromium evaporation were studied, Cr thin films were deposited. XRD analysis showed that the three carbides Cr _ 3C _ 2o _ (Cr _ 7C _ 3) and C _ (23) C _ 6 were formed under the condition of diamond growth. It was found that Cr _ 3C _ (2) C _ (3) and C _ (23) C _ (6) were formed in hydrogen methane atmosphere. The discontinuous evaporation of chromium can be realized by decarbonization, and the formation of Cr3C2 phase is the main reason that lead to the difficulty of evaporation of chromium source through the phase analysis of chromium source in different experimental stages. It is the first time to put forward the method of alternating growth of diamond and chromium carbide in space: according to the difference of growth speed between chromium carbide and diamond, short time and many times steam chromium, long time and many times growth diamond, The diamond-chromium carbide composite film was prepared by controlling the amount of chromium-vaporizing, and the diamond film was deposited on the diamond-chromium carbide composite interlayer. The surface morphology of the film was studied by means of SEMX XRD. The phase was analyzed. This paper has some innovations in the following aspects: for the first time, the solid chromium is introduced into the hot filament chemical vapor device and the chromium is evaporated only by the heat radiation of the hot filament. As far as we know, this is the first time that Cr thin films have been successfully prepared with hot filament CVD. Chromium carbide film and diamond-chromium carbide composite film.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2010
【分类号】：TB383.2

【引证文献】