Low Temperature GaN Epitaxy Using Ga(mDTC)_3 Precursor

摘要

GaN thin film growth using vapor-phase epitaxy is a well-studied process that typically requires growth temperatures in the range of 950～1000 ℃. Tris(N,N-dimethyldithiocarbamato)-gallium(III) (Ga(mDTC)_3) was investigated in this study, a new precursor material for the GaN film deposition by hot-wall VPE technique, in an effort to reduce the growth temperature. TMGa, HC1 and NH3 were used as gas source precursors. Parametric growth studies were performed to optimize the growth temperature and the distance between the gas outlet and the substrate (z-position) using this process. The optimal growth temperature was found to be 850 ℃, and the optimal z-position was determined to be in the range of 12.5 to 15 cm. XRD studies showed that this growth method produces high-crystalline GaN thin films at relatively lower deposition temperature compared to existing growth techniques.