Diamond nucleation on silicon during bias treatment in chemical vapour deposition as analysed by electron microscopy

Abstract

Abstract The phases that form on the substrate at different stages of the bias pretreatment that precedes the plasma chemical vapour deposition of textured and oriented diamond on Si (100) are investigated by transmission and scanning electron microscopy. First, a 10-nm thick layer of epitaxially oriented β -SiC crystallites is formed. Supersaturation of this layer with carbon leads to the formation of subcutaneous diamond nuclei in registry with the SiC lattice. These nuclei are exposed in the course of the bias treatment or during diamond growth through the etching action of the plasma and give rise to the growth of epitaxially oriented diamond. The β -SiC layer acts therefore among other things as a template that transfers the substrate orientation to the diamond crystals.