Investigations of He+ implantation and subsequent annealing effects in InP

The influence of 70 keV He+ ion implantation and subsequent annealing of Cz–indium phosphide (InP) samples has been investigated using a slow positron beam-based Doppler broadening spectrometer. Three samples with ion fluences of 1 1016, 5 1016 and 1 1017 cm 2 were studied in the as-implanted condition as well as after annealing at 640 8C for times between 5 and 40 min. It was found that the line-shape parameter of the positron–electron annihilation peak in the implanted layer increases after 5 min annealing, then after longer annealing times it starts to decline gradually until it reaches a value close to the value of the as-grown sample. This implies that vacancy-like defects can be created in InP by He implantation followed by shortthermal annealing at T > 600 8C. Comparison of the results with a study where cavities were observed in He-implanted InP has been carried out