The understanding of defects and their effects has become a critical issue in ion-implantation processing of aggressively designed integrated circuits. A "new" understanding of these interactions has recently emerged which holds that the total number of defects do not contribute as significantly to processing problems as do the excess defects, where "excess defects" represents a local surplus of one defect over its compliment. The purpose of this study is to engineer ion-induced defects in an effort to either control or eliminate these local imbalances. A technique was used to selectively eliminate interstitial-type defects typically found at the amorphous-crystal (a-c) interface following regrowth of an amorphous layer. This technique involved a method in which high-energy ions were used to inject vacancies into the near-surface region to act as recombination sites for the interstitials. Studies were done on pre-amorphized Si substrates with and without a prior MeV implant of Si~+-ions. These comparative studies indicate that without MeV implantation, significant damage persists at the location of the a-c interface even after 800°C annealing. The damage was absent in the sample implanted with MeV Si~+-ions. Thus, the interfacial defects from the amorphizing implant, believed to be responsible for the enhanced diffusion of boron implanted within an amorphous layer, have been successfully eliminated.
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