异质外延立方氮化硼薄膜的微结构研究

Microstructure of heteroepitaxial cubic boron nitride thin films: a HRTEM study

利用离子束辅助沉积技术在金刚石薄膜衬底上制备立方氮化硼薄膜,傅立叶变换红外谱的结果表明,在高度(001)织构金刚石薄膜衬底上沉积的立方氮化硼薄膜是纯的立方相,而在多晶金刚石薄膜衬底上制备的立方氮化硼薄膜中还含少量的六角氮化硼。高分辨透射电镜的分析表明,在金刚石晶粒上异质外延的c BN直接成核于金刚石衬底,界面没有六角氮化硼过渡层;而在含有大量缺陷的晶粒边界,存在六角氮化硼的成核与生长。

Cubic boron nitride (c-BN) thin films were prepared on chemical vapour deposition diamond substrates by ion beam assisted deposition.Theses films were characterized by transmission Fourier transformed infrared spectroscopy and high-resolution transmission electron microscopy.The results proved that the epitaxial c-BN thin films had nucleated directly on top of diamond substrates without any intermediate hexagonal BN layer that is commonly observed on Si substrates.The c-BN films on the highly (001)-oriented diamond were pure cubic phase,while these c-BN films on thin polycrystalline diamond contained a small amount of hexagonal phase.The presence of hexagonal BN was due to defects within the grain boundaries of the underlying polycrystalline diamond substrates.