Resistance of group III nitrides irradiated with a 10 keV electron beam; comparison of the cathodoluminescence emission of GaN quantum dots, quantum wells and (Al)GaN epitaxial layers

摘要

We present a comparative Study of the in situ modifications induced by a 10 keV electron beam in gallium nitride (GaN) quantum wells and quantum dots as, well as in ELOG (epitaxial laterally overgrown GaN) and AlGaN epilayers. Cathodoluminescence (CL) experiments were performed to investigate the room temperature evolution of the optical properties as a function of the beam Current density. Higher dot resistance is much more apparent when the beam Current density is larger than about 6 A cm(-2). Recombination enhanced diffusion of defects is involved in the degradation of the CL signal. The two serial mechanisms inferred to be present in the degradation process are described.