Abstract
This work is concerned with, the determination of some of the properties of GaAs after bombardment with , H1+, H2+, H3+, O2+ and Ar+ ions. The capacitance-voltage, Copeland, Hall-effect and resistivity measurement methods have been employed as diagnostic techniques. The carrier removal rate, i.e. number of charge carriers removed per incident ion, has been determined as a function of the ion, ion energy, ion dose, implant temperature and annealing temperature in order to characterize the electrical effects of the radiation damage caused by the ions. It was demonstrated that the carrier removal caused by implanting equivalent doses of H1+, H2+ and H3+ ions into GaAs was identical and approximately independent of the ion energy in the range 300-500 keV. Carrier removal profiles have been measured in annealed, oxygen implanted GaAs. A dose of 10 15 O+/cm2 produced a resistivity of about 108 O/ over a layer 0.5 - 0.6 micron thick, but no significant electrical compensation was observed from doses less than 1013 O+/cm2. However, doses of 10 11 to 5 x 1012 O+/cm2 produced resistivities of 108 - 109 O/ without subsequent annealing. It has been observed that the implants performed at 200°C resulted in less radiation damage than for room temperature implantations.Compared with unimplanted GaAs, there was an increase in resistivity of about 30% and 100% for doses of 3 x 1013 and 1014 Ar+/cm2 respectively, after annealing at 700°C.