The Influence of Ion Implantation on the Optical Parameters - Refraction and Extinction Coefficients οf the Oxygen-Enriched Layers Covering GaAs Implanted with Indium Ions

The semi-isolating GaAs (100) samples irradiated with fluence 3 × $10^{15}$ ions/$cm^{2}$ of $In^{+}$ ions were characterized by using the methods: Rutherford backscattering spectroscopy, nuclear reaction analysis and ellipsometric spectroscopy. The values of the thicknesses layers enriched with oxygen and the implanted were determined by the methods of nuclear reaction analysis and Rutherford backscattering spectroscopy. Multilayer models were applied for determination of the optical constants (refraction and extinctions coefficients) of investigated samples. The thickness of native oxide covering the surface of implanted GaAs and refraction coefficients were increased after implantation with indium. The spectrum of extinction indexes as a function of light wavelength has two bands near the light wavelengths 400 nm and 480 nm. The observed effects can be interpreted as formation of local oxides of In and InAs precipitates or ternary alloys in enriched with oxygen layers at the surfaces of implanted GaAs.