Si Ion Implantation into GaAs

Isothermal annealing experiments were carried out at annealing temperatures up to 900°C for Cr-doped GaAs implanted with St at 60 and 130 keV and for doses ranging from approximately 10 12 to 10 15 /cm 2 . The implantation induced damage recovery was examined from the behavior of the surface carrier concentration and mobility. Optimum anneal conditions which gave a maximum value of the surface carrier concentration were experimentally determined. High purity epitaxial GaAs was also used as a substrate. After annealing under optimum conditions, the carrier concentration and mobility profiles were measured. For doses ≤10 13 /cm 2 , Gaussian type carrier concentration profiles were obtained indicating the small effect of radiation-enhanced diffusion. Almost the same mobility values as these of vapor epitaxial GaAs were obtained at room and liquid nitrogen temperatures for an implanted layer in high purity epitaxial GaAs.