Laser annealing of radiation defects in low disordered layers

Abstract

Carrier concentration and mobility dependences on the annealing temperature have been compared for the cases of thermal (10 min) and laser (8 ms) annealing of silicon, implanted with low doses of P⁺ ions. It was found that the recovery of concentration and mobility depended on the heating time in different ways. The laser annealing requires higher temperatures for mobility recovery then the thermal treatment. The same temperature shift was observed for increase of carrier concentration but only after doses less than 3.10¹²m^?2. When the doses exceeded 3.10¹² cm^?2 laser and thermal annealing resulted in equal electron concentrations providing the equality of heating temperatures. Annealing of disordered regions was accounted for the mobility recovery. The increase of electron concentration was explained as an instantaneous decay of defect-impurity complexes. To check the validity of the assumptions laser annealing of electron and light ions irradiated materials was investigated.