Effect of in Concentration on the Optical Lattice Vibrations in Quaternary AlxInyGa1-x-yN Alloys

Abstract

Fourier transform infrared (FTIR) spectroscopy has been utilized to measure long-wavelength optical lattice vibrations of high-quality quaternary AlxlnyGa1-x-yN thin films at room temperature. The AlxlnyGa1-x-yN films were grown on c-plane (0001) sapphire substrates with AlN as buffer layers using plasma assisted molecular beam epitaxy (PA-MBE) technique with indium (In) mole fraction y = 0.0 to 0.10 and constant aluminium (Al) mole fraction x = 0.06. The experimental results indicated that the AlxlnyGa1-x-yN alloys had two-mode behavior, for the A1 (LO) and E1 (TO) modes.