LASER-INDUCED REDUCTION OF CARRIER ACTIVATION-ENERGY IN ZN-IMPLANTED GAAS

It has been recently established that the crystallinity of-ion-implant ed GaAs samples can be restored by using a low-power pulsed-laser anne aling (LPPLA) technique. In this paper we report an improvement of car rier activation achieved after low-temperature processing (added to LP PLA) at temperatures low enough to avoid substantial losses of As. By using this combination of techniques we have reduced the sheet resisti vity to values comparable with those obtained by standard techniques w ithout any specimen encapsulation (or similar) processing. The pretrea tment by LPPLA seems to reduce the Zn activation threshold down to val ues which prevent the sublimation of As.