Electron-induced nitridation of GaAs(100) with ammonia

Abstract

Nitridation of GaAs(100) was observed at temperatures ranging from 323 to 523 K by simultaneous exposure of the substrate to a molecular ammonia flux and electron irradiation in an ultrahigh vacuum environment. Incident electron energies of 350–3000 eV were employed. A GaN surface film formed. GaN formation was related to the amount of chemisorbed NH3 and the electron beam flux. The nitridation process was nonthermal. Two possible reaction schemes involving dissociative electron attachment and dissociative electron ionization are discussed.