Theoretical study of the Cl desorption reaction induced by H2 in the chloride atomic layer epitaxy

摘要: Abstract The chloride ALE (atomic layer epitaxy) technique is now common to grow GaAs crystals, where the GaCl molecule used supply Ga atoms for As dangling bond site. present ab initio molecular orbital calculations predict that Cl are desorbed as HCl by single-site reaction which induced H 2 . scheme represented > + → GaH , driven concerted electron delocalizations among those four atoms. It shown endothermic amount of 30 kcal/mol and occurs through four-centred transition state “late-barrier” type. activation energy estimated be 37–44 kcal/mol, agrees well with experimental value 40–50 kcal/mol.