Atomic Force Microscope Observation of the Change in Shape and Subsequent Disappearance of “Crystal-Originated Particles” after Hydrogen-Atmosphere Thermal Annealing

The change in shape and the disappearance of “crystal-originated particles (COPs)” on silicon (111) and (001) surfaces after high-temperature annealing in hydrogen (H2) atmosphere were observed using an atomic force microscope (AFM). It was found that after a very short anneal at 1000°C in H2 atmosphere, the COP width across the wafer surface increases and its depth into the wafer bulk becomes more shallow. Also, as the H2 annealing temperature increases, the time taken for complete COP disappearance decreased. The process of the change in shape and the subsequent disappearance of COPs on silicon (111) and (001) surfaces after H2 annealing was characterized and discussed in terms of the etching effect and reconstruction of silicon atoms.