Raman scattering studies on hydrogen ion-implanted GaN

Abstract

The metal organic chemical vapour deposition (MOCVD) grown unintentionally doped n-type GaN epitaxial layers on sapphire substrates have been implanted with H + for various doses from 10 14 to 10 16 cm −2 with multiple energies ranging from 40 to 120 keV. Raman spectra have been recorded on as-grown, H +-implanted GaN samples and on virgin sapphire substrate. E 2 (high) and A 1(LO) Raman modes of GaN layer have been observed and analysed. The behaviour of Raman shift, FWHM and area of GaN modes with H + dose are explained on the basis of hydrogen substituting nitrogen atom, implantation-induced lattice damage and light attenuation by lattice damage in GaN layer.