Early events in the mechanism of single-source chemical vapor deposition of zirconium and hafnium diboride: a computational investigation

Abstract

Chemical vapor deposition (CVD) of group 4 metal-diboride ceramics from a single source is a versatile technique that finds many applications from hypersonic flight to microelectronics. Though the kinetics of CVD have been studied extensively—allowing significant process improvements—a mechanistic understanding of the process has yet to be attained. Computations suggest two plausible reaction pathways—one higher-energy and the second lower—that correlate well with experimental results reported in the literature, explaining phenomena such as high-temperature deposition resulting in films overstoichiometric in boron. These insights offer a new perspective that may be instrumental in the rational design of new precursors for single-source CVD.