Large area and rapid electron beam annealing for high-quality epitaxial GaN layer

Abstract

This paper reports significant enhancement of the crystalline quality of nanoscale GaN thin films by a large-area and rapid electron beam annealing (EBA) technique. A low full width at half maximum of only 185 arcsec of the X-ray rocking curve indicates a high-quality GaN epilayer, which is attributed to efficient energy transfer from the large-area electron irradiation into the film in a single exposure without the need of electron beam scanning. The high crystalline quality of the GaN epilayer was also evidenced by the very clear lattice fringes in the high-resolution transmission electron microscopy image. A smooth surface with a low surface roughness of the GaN layer also reveals low damage caused by the rapid EBA treatment. The promising results demonstrate that the low-damage, large-area, and rapid EBA is an effective technique for numerous applications that require an efficient annealing process with a low thermal budget.