Abstract
In both cases of quenched and HBO2-molecule-irradiated Si(111) surfaces, corner holes are observed to exist along the boundaries between 7×7 and disordered structural domains. From the analysis of the bias-dependent STM images, it was found that the corner holes included complete stacking fault and dimer structures in the second layer, i.e., a complete corner hole. This result strongly indicates that the complete corner holes play important roles in both the formation and stabilization processes of the dimer-adatom-stacking fault (DAS) structure. In addition, the formation of a structure similar to that of the corner hole was often observed at the boundaries of three out-of-phase c(2×8) structural domains in quenched surfaces, which may result in nucleuses for the formation of the complete corner hole.