Electrical Properties of GaAs Implanted with High Energy (100meV) 28Si and 120Sn Ions
Single crystal n-GaAs substrates have been implanted at 300 K with 100 MeV 28Si and 120Sn ions to a dose of 1x1018ions/m2 independently. The electrical properties of these samples has been investigated and compared after implantation and annealing up to 850 °C by current voltage (I-V) measurements. It has been observed that the I-V curves for the samples implanted with 28Si ions show p-n junction like characteristics which then show a linear I-V characteristics for the annealing treatment between 150-550 °C. Annealing the samples at 650 °C results in a typical diode like I-V characteristics which become less non-linear after further annealing at 750 °C. Further annealing at 850 °C results in to a back ward diode like behavior. However the I-V curves for the samples implanted with 120Sn ions and annealed up to 450C were linear which then show a weak non linearity for the annealing treatments between 550C-750C. After 850C annealing the samples show a strong nonlinearity typical of a p-n junction. The temperature dependence of resistance of both 28Si and 120Sn implanted GaAs samples after implantation and different annealing steps are investigated and the possible conduction mechanisms are discussed.