Impurity effect on internal gettering in Czochralski silicon

With the rapid reduction in feature size of ultra large scaled integrate (ULSI) circuits, the microdefects in Czochralski silicon (Cz-Si) such as oxygen precipitates play increasingly important roles in the reliability of devices. In recent years, the novel properties of impurity (nitrogen, germanium and carbon) doped Cz-Si materials have attracted increasingly considerable attentions. In this presentation, the recent processes of our group’s investigation on the internal gettering (IG) structures in aforementioned Cz-Si wafers have been reviewed. It has been considered that the density of gettering sites for metallic contamination are higher than that of the normal wafers and the denuded zone (DZ) with the desirable width for ULSI device fabrication can be both generated. The comparison of the generation of IG structures among the common silicon wafer and the nitrogen, germanium and high carbon content silicon wafers has been presented and the impurity engineering for the Cz-Si materials has also been emphasized.