Au/GaAs(100) interface Schottky barrier modification by a silicon nitride intralayer

We report a modification by thin silicon nitride intralayers of the Au/n-GaAs(100) Schottky barrier height. Thin intralayers were obtained by nitridation of evaporated Si films on decapped GaAs substrates in an argon–nitrogen mixture plasma. The nitridation was performed at a beam energy <40 eV, with 573 K sample temperature. Gold was deposited to study in situ the Schottky barrier formation process with x-ray photoelectron spectroscopy. Internal photoemission spectroscopy and current–voltage measurements were used to evaluate the barrier modification on fully formed interfaces. Such a modification was analyzed in terms of theoretical calculations of the dipole created by the substrate–intralayer bonds.