New and Novel Superhard Coatings Prepared by Electron-Cyclotron-Resonance Plasma-Enhanced Chemical Vapour Deposition

寻找具有新特性的新型超硬材料不仅对于理解这些材料的科学和技术非常重要，而且对于评估其应用的全部潜力也非常重要。作为共价键合的结果，四种元素硼（B）、硅（Si）、碳（C）、氮（N）和/或可能的氧（O）可以形成超硬材料。在过去的十年中，大量的努力集中在二元和三元组分上。初步调查显示，Si B C N四元体系的研究为在极端制备条件下采用先进的制备技术创造新型超硬材料提供了可能，本研究在近几年金刚石、立方氮化硼薄膜和纳米结构金刚石/碳化硅复合薄膜的成功合成之后，本文尝试用电子回旋共振微波等离子体辅助化学气相沉积（ECRMWCVD）技术在Si-B-C-N-（O）体系中制备新型超硬涂层。系统地研究了这种新材料的生长机理，碳、氮、氢、氧的作用，薄膜的晶体结构和性能。

The search for new superhard materials with novel properties is important not only for an understanding of the science and technology of these materials but also for evaluating the full potential of their applications. As a result of covalent bonding, the four elements boron (B), silicon (Si), carbon (C), nitrogen (N) and/or probably oxygen (O) can form superhard materials. In the last decade, much effort has concentrated on binary and ternary components. The preliminary investigations lead one to believe that the Si¿B¿C¿N quanternary system may give opportunity to the creation of new type of superhard materials by using the advanced technique operating at the extreme preparation conditions.In this proposal, following the successful synthesis of diamond, cBN thin films and nanostrutured superhard diamond/ß-SiC composite films in the past few years, we make an attempt to synthesize new type of superhard coatings from the Si-B-C-N-(O) system by electron-cyclotron-resonance microwave plasma assisted chemical vapour deposition (ECRMWCVD). The growth mechanism of the new material, the role of carbon, nitrogen, hydrogen and oxygen, the crystal structure as well as the properties of the deposited films will be investigated systematically.