Raman scattering studies on hydrogen ion-implanted GaN

The metal organic chemical vapour deposition (MOCVD) grown unintentionally doped n-type GaN epitaxial layers on sapphire substrates have been implante d with H+ for various doses from 10(14) to 10(16) cm(-2) with multiple ener gies ranging from 40 to 120 keV. Raman spectra have been recorded on as-gro wn, H+-implanted GaN samples and on virgin sapphire substrate. E-2 thigh) a nd AI(LO) Raman modes of GaN layer have been observed and analysed. The beh aviour of Raman shift, FWHM and area of GaN modes with H+ dose are explaine d on the basis of hydrogen substituting nitrogen atom, implantation-induced lattice damage and light attenuation by lattice damage in GaN layer. (C) 2 001 Elsevier Science B.V. All rights reserved.