Edge emissions of ion-implanted CdS

Edge emissions of CdS crystals implanted with Li+, N+, Ne+ and P+ are studied. Li and P are found to form acceptors and give rise to I1 lines in the blue and donor-acceptor pair recombination emissions in the green. N gives rise to two kinds of I2 lines (excitons bound to neutral donors) and donor-acceptor pair recombination emissions. An acceptor due to a defect is found in N+ and Ne+ implanted CdS. The temperature range of thermal treatment where impurity centers are formed is also investigated. The relationship among impurity centers produced by N+ implantation is, moreover, discussed based upon the results obtained here and previous works. (author)