Self-assembled GaN hexagonal micropyramid and microdisk

Abstract

The self-assembled GaN hexagonal micropyramid and microdisk were grown on LiAlO2 by plasma-assisted molecular-beam epitaxy. It was found that the (0001¯) disk was established with the capture of N atoms by most-outside Ga atoms as the (1×1) surface was constructing, while the pyramid was obtained due to the missing of most-outside N atoms. The intensity of cathode luminescence excited from the microdisk was one order of amplitude greater than that from M-plane GaN.