Characterization of Stress in GaN-on-Sapphire Microelectromechanical Systems Structures Using Micro-Raman Spectroscopy

Micro-Raman ( Raman) spectroscopy is an e cient, non-destructive techniquewidely used to determine the quality of semiconductor materials and microelectrome-chanical systems. This work characterizes the stress distribution in wurtzite gal-lium nitride grown on c-plane sapphire substrates by molecular beam epitaxy. Thiswide bandgap semiconductor material is being considered by the Air Force ResearchLaboratory for the fabrication of shock-hardened MEMS accelerometers.