Strain analysis of the GaN epitaxial layers grown on nitridated Si(111) substrate by metal organic chemical vapor deposition

The strain analysis of GaN film on nitridated Si(111) substrate with different growth times between 0 and 660 s via metal organic chemical vapor deposition (MOCVD) was conducted based on the precise measurement of the lattice parameters by using high-resolution X-ray diffraction (HR-XRD). The nitridation time (NT) was changed at a fixed growth condition. The a- and c-lattice parameters were measured, followed by the in-plane and out-of-plane strains. Then, the biaxial and hydrostatic components were extracted from the total strain values obtained, and were then discussed in the present study as functions of the NT. The biaxial strain and stress are also strongly affected by the non-uniformity of the SiNx buffer layer thickness.