Abstract Hydrogenated amorphous carbon thin films (a-C:H) do not show good adhesion on ferrous alloys. When a silicon-containing intermediate thin film is chosen, deposition temperatures of at least 300 °C are necessary to provide adequate adhesion. However, a new approach is introduced to achieve similar results at lower temperatures: a selective chemical hydrogen plasma etching before the carbonaceous film deposition. The effect is known but its physicochemical mechanism and kinetics remain open. We have investigated the role of hydrogen etching in the modification of the outermost and innermost interfaces of a-SiCx:H interlayers. The results show that hydrogen radically modifies the interlayer thickness in the outermost region and increases the C/Si ratio in the innermost. Moreover, the hydrogen etching allows the formation of more C C bonds at the outermost interface, which is correlated to better adhesion. Finally, we proposed a mechanism in order to explain physical and chemical changes caused by hydrogen etching.

中文翻译：

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aC:H/a-SiC x:H 界面处的氢等离子体蚀刻机制：aC:H 粘附的关键因素

摘要 氢化非晶碳薄膜 (aC:H) 在铁合金上没有表现出良好的附着力。选择含硅中间薄膜时，必须至少300℃的沉积温度来提供足够的粘合性。然而，引入了一种新方法以在较低温度下获得类似的结果：在碳质膜沉积之前进行选择性化学氢等离子体蚀刻。这种作用是已知的，但其物理化学机制和动力学仍然是开放的。我们研究了氢蚀刻在改变 a-SiCx:H 夹层的最外层和最内层界面中的作用。结果表明，氢从根本上改变了最外层区域的层间厚度，并增加了最内层的 C/Si 比。而且，氢蚀刻允许在最外层界面形成更多的 CC 键，这与更好的附着力相关。最后，我们提出了一种机制来解释氢蚀刻引起的物理和化学变化。