Scanning photoluminescence technique: application to defect recovery of ion implanted InP

The scanning photoluminescence technique at room temperature was applied to characterize the quality of ion-implanted indium phosphide as well as to investigate the defect recovery as a function of the annealing temperature. Doses ranging from 1010 to 1014 ions cm-2 were implanted with either neon or magnesium ions. The intensity of the photoluminescence response was found to be related to the ion dose. Two different substrates were used: an iron-doped semi-insulating one and an undoped one. The results were similar. Nevertheless, the sensitivity was higher for the undoped substrate. After thermal anneals ranging from 200 up to 800oC the average PL intensity was again recorded and was found to increase with the progressive recovery of the defects. After an anneal at 750oC the PL response was comparable to the signal obtained in the case of an annealed reference. The contribution of a doping impurity in a semi-insulating substrate was not clearly evidenced, the PL signal being dominated by the remaining non-radiative centres. (Author)