Behavior of Defects Induced by Metallic Impurities on Si(100) Surfaces

Abstract
The formation of defects induced by Ni, Cu and Fe and their retardation by intrinsic gettering (IG) were studied under several heat treatments. The behavior of Fe in Si was different from that of Ni and Cu. After annealing at 1150°C and subsequent cooling, shallow pits (SP) due to Ni and Cu precipitates were observed only at the surface. Fe precipitation was obtained by holding at temperatures below 850°C, where Fe was supersaturated in the matrix. We believe that metal precipitation is dominated by the diffusion rate. During additional oxidation, oxidation-induced stacking faults (OSF) were transformed from each precipitate. It seems that metal precipitates act as nuclei of OSF. Effects of IG for the three elements were compared. The retardation of defects induced by Fe was less than that of Ni and Cu. This difference is closely related to the growth rate of Fe precipitates.