MEASUREMENT OF THE DEPTH DISTRIBUTION OF ION-BEAM ETCHING-INDUCED DAMAGE IN ALGAAS GAAS MULTIPLE-QUANTUM-WELL STRUCTURE/

The defect depth distribution caused by a 500 eV nitrogen ion beam etc hing (IBE) of an Al0.35Ga0.65As/GaAs multiple quantum well (MQW) struc ture was investigated by confocal photoluminescence (PL) measurements on a beveled section of the sample. The beveled section with an extrem ely small inclination angle necessary for the high depth resolution wa s fabricated by the IBE itself. Compared to other ion beam or plasma a ssisted etching processes reported, e.g., Ar-IBE, the 500 eV nitrogen IBE yields a very low defect density. A model including diffusion effe cts for the description of the profile gives a value of 4x10(-15) cm(2 )/s for the defect diffusion coefficient. (C) 1997 American Institute of Physics.