Investigations on H + and He + implantation effects in n-InP Using Raman Scattering

Abstract

The LEC grown (1 1 1) n-InP have been implanted with H + and He + for various doses ranging from 10 12 to 10 16 cm −2. The Raman spectra of TO and LO modes in as-grown, H + and He + implanted n-InP are recorded and analyzed. FWHM of the LO Raman mode decreases while that of the TO mode remains the same for low doses up to 10 15 cm −2 for H + and 10 14 cm -2 for He +. For higher doses the FWHM of both the modes increase, the increase being larger for TO mode. LO–TO splitting decreases with the increase of dose, for all doses. The ratio between the area under TO and LO modes decrease at low doses but increase for higher doses. These results have been explained with carrier concentration reduction at low doses and lattice damage at high doses. Annealing effects on these Raman mode parameters have also been studied on the as-grown and implanted n-InP, where the thermal annealing anneals partially the implantation induced lattice defects.