Fabrication of GaN nanodots via GaN thermal decomposition in H2 atmosphere

Abstract

GaN nanodots were fabricated by thermal decomposition of GaN in H2 atmosphere at high temperatures. By varying annealing time and temperature, it was found that dot size and density were highly dependent on annealing conditions. Surface morphology of the sample indicates that the dot formation mechanism is chemical erosion under H2 flow. The etching proceeds in lateral directions, and the dots are formed in hexagonal pit areas. The fitted activation energy of GaN decomposition agrees well with the chemical properties of GaN in the experimental conditions.