Passivation of bulk and surface defects in GaAs grown on Si substrate by radio frequency phosphine/hydrogen plasma exposure

The effects of PH3/H-2 plasma exposure on GaAs grown on Si substrate (GaAs/Si) were investigated. It was found that corporation of P atoms in H-2 plasma not only hydrogenated the defect-related recombination centers of GaAs/Si epilayer, but also phosphidized the surface region of GaAs/Si epilayer by forming a phosphidized layer, Electron beam-induced current measurement directly proved that the defect-related dark spot density was effectively reduced by adding P atoms into the pure H-2 plasma. In addition, PH3/H-2 plasma exposure greatly increased the minority carrier lifetime properties and decreased the saturation current of the GaAs p(+)-n junction structure grown on Si substrate.