An atomic scale modeling of nitrogen vacancies in Ga-rich gallium nitride (GaN) buffer layer was conducted by Car-Parrinello molecular dynamics (CPMD) method in the frame of density functional theory (DFT), and stress tensors in defective bulk gallium nitride were calculated. The results indicated that the gallium nitride buffer layer with lots of nitrogen vacancies facilitated stress relaxation and tensile stress reduction in epitaxy layer. The compressive stress in the gallium nitride buffer layer was increased with the decrease of the N/Ga ratio. The modeling of nitrogen vacancies in gallium nitride has provided some new insights into tensile stress reduction by Ga-rich gallium nitride buffer layer on atomic level.
|Number of pages
|International Journal of Nonlinear Sciences and Numerical Simulation
|Published - 1 May 2009