The effects of post-H+implantation on electron traps that are induced byP+implantation (300 keV,1×109 cm−2) has been studied by deep-level transient spectroscopy.H+implantation is performed at room temperature to a dose of2×1010 cm−2in the range 30–120 keV. The post-H+implantation partly decreases the concentration of the electron traps induced byP+implantation, although it increases the concentrations around the projected range ofH+.The annealing effect is ascribed to the reaction of preexisting defects with point defects induced by postimplantation. Peaks are observed in the reduction ratio profiles of the preexisted trap concentrations versus the distance from the projected ranges of postimplantation. The highest values of the reduction ratios in each postimplantation tend to decrease with increasing distance between the projected ranges ofP+andH+.This is due to the decrease of the supply of point defects caused by postimplantation with increasing distance. We compare the reduction ratio profiles of the dominant three electron traps (Ec−0.12,0.15, and 0.39 eV). ©1997 American Institute of Physics.