A Nucleation Site and Mechanism Leading to Epitaxial Growth of Diamond Films

A diamond nucleation site responsible for epitaxial growth of diamond on silicon by chemical vapor deposition (CVD) is identified in high-resolution transmission electron microscopic images. Other sites in the same sample leading to polycrystalline growth, but deleterious to epitaxial CVD growth, are also described. A mechanism for the heteroepitaxial growth of diamond is suggested, in which etching of the nondiamond carbon binder exposes and removes nonadherent nanodiamond nuclei, leaving intact only those directly nucleated on the silicon substrate. This work enhances our understanding of diamond nucleation and heteroepitaxial growth and its potential applications.