Diffusion, activation, and regrowth behavior of high dose P implants in Ge

Abstract

Time evolution of the chemical profile, electrical activity, and regrowth of P implanted in Ge at a concentration above the maximum equilibrium solubility is investigated at 500°C rapid thermal annealing temperature. During the first anneal, a second, epitaxial regrowth of a part of the amorphous layer leads to P trapping in substitutional sites at a level of about 4×1020atoms∕cm3. However, nonsubstitutional P atoms frozen in the crystal at high concentration during recrystallization form large, inactive precipitates of peculiar circular shape. Simultaneously, long annealing time leads to continuing, extensive P out- and indiffusion affecting both the P chemical profile and junction sheet resistance.