Evidence and modeling of anomalous low concentration arsenic inactivation

Experimental results are discussed that indicate that implanted arsenic is sometimes transported by large populations of a mobile species that is neutral at room temperature, causing inactivation throughout the profile and unexpectedly high sheet resistances. This transport path occurs in strictly low concentration diffusion and in the early stages of high concentration diffusion, prior to precipitation. Novel models are presented that fit low concentration chemical profiles, anomalous electrical data, and early high concentration data. One of the models successfully predicts sheet resistances in high concentration profiles that have not yet shown evidence of precipitation, suggesting that interstitial arsenic is the precursor to normal high concentration inactivation.<>