Annealing of Defects in Ion-Implanted Layers by Pulsed Laser Radiation

Abstract

The annealing of ion-implanted layers by laser pulses of high power is extremely interesting for several reasons. First of all, sufficiently short light pulses with photon energies exceeding the forbidden band of the semiconductor will heat only thin surface layers. As a result, it is possible to anneal radiation defects in the implanted layers without undesirable heating of the bulk. Secondly, use of focused light beams makes it possible to carry out local annealing at different temperatures all over the sample. Finally, pulsed laser irradiation is characterized by a time constant of 10-3–10-11 sec, and is accompanied not only by heating but also by effective ionization, shock waves, and quenching. All these factors affect the annihilation of defects and their interaction with impurities.