Modeling of SiGe deposition using quantum chemistry techniques for detailed kinetic analysis

Modeling of chemical vapor deposition (CVD) processes requires knowledge of the gas-how dynamics and chemical reactions occurring in the reactor. In order to go beyond simple growth rate predictions based on lumped kinetics from incomplete experimental kinetic data, quantum chemistry techniques are used to investigate kinetics of chemical reactions involved in the deposition of SiGe heterolayers. Gas-phase reaction pathways for GeH4 decomposition are proposed and the relevant reaction rates are evaluated. Cluster calculations are presented to determine binding energies of H, Cl on Si, Ge and SiCe surfaces and surface migration of H and Cl adatoms on Si and SiGe surfaces is investigated. The reactions are summarized into a detailed reaction mechanism to predict growth of Si1-xGex heterolayers within the realistic thermal-fluid environment present in a CVD reactor. (C) 2000 Elsevier Science Ltd. All rights reserved.