Nano-scale properties of defects in compound semiconductor surfaces

The present work reviews atomic-scale properties of point defects and dopant atoms exposed on and in cleavage surfaces of III–V and II–VI semiconductors. In particular, we concentrate on the identification of the types of defects and dopant atoms, the determination of the localized defect states, the electrical charge, and lattice relaxation, as well as the measurement of the interactions between different defects and/or dopant atoms. The physical mechanisms governing the formation of defect complexes, the compensation of dopant atoms, the pinning of the Fermi level, and the stability of defects are discussed in the light of the available theoretical information and experimental results obtained mostly by scanning tunneling microscopy.