Epitaxial Mechanism of Diamond Crystal Nucleation on a Mo {110} Substrate during Chemical Vapor Deposition

Abstract

The epitaxial mechanism of diamond crystal nucleation by the (110) face on the Mo(110) face during chemical vapor deposition on a molybdenum plate has been established. It is shown that, under the synthesis conditions in use, only cubic sectors of diamond crystals continue to grow according to the tangential mechanism, whereas octahedral sectors are characterized by some complex nonequilibrium mechanism of normal growth. In particular, a situation where the {111} faces are absent and octahedral sectors grow by {100} layers of three orientations, which make a reentrant cube angle and are twins of the initial crystal on one of its {111} faces, has been observed. Geometric analysis of five-fold aggregates of multiply twinned diamond crystals with a shared 〈110〉 axis shows that at least one narrow truncating lateral {111} face oriented parallel to the shared 〈110〉 axis should occur.