Enhancement of surface decomposition using supersonic beam: Direct evidence from GaN quantum dot formations on AlGaN surfaces in gas-source molecular beam epitaxy

The enhancement effect of surface decomposition using supersonic beam was found for the first time, in the fabrication of GaN quantum dots on AlGaN/6H-SiC(0 0 0 1) surfaces by gas-source molecular beam epitaxy. GaN quantum dots were successfully fabricated using Si which was supplied by supersonic beam of CH₃SiH₃, while the GaN dots could not be formed using usual beam of CH₃SiH₃. The optical properties of the fabricated GaN quantum dots were investigated by photoluminescence measurements. The advantage by using supersonic beam technique in the enhancement of surface reaction was demonstrated.