ANNEALING EFFECTS ON ELECTRICAL CHARACTERISTICS OF GaAs IMPLANTED WITH 100 MeV 56Fe and 120Sn IONS

Single crystal n-GaAs substrates have been implanted at room temperature with 70 MeV 56Fe and 120Sn ions to a fluence of 1x1018 ions/m2. The electrical characteristics were investigated after implantation and annealing up to 850°C by current voltage measurements. Low temperature resistance measurements of these samples show that the 56Fe implanted samples annealed to 350°C and 120Sn implanted samples annealed to 450°C are dominated by a variable range hoping conduction, whereas for the 56Fe implanted samples annealed to 450°C and 550°C and 120Sn implanted samples annealed to 550°C and 650°C the electrical conduction is due to hoping between neighboring defect sites