2009/11/30 by Ono, Tomoya, Saito, Shoichiro
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.0911.5608
Evidence of the absence of the clear electron spin-resonance signal from Ge dangling bonds (DBs) at Ge/GeO2 interfaces is explored by means of first-principles electronic-structure calculations. Comparing the electronic structures of the DBs at Si/SiO2 and Ge/GeO2 interfaces, we found that the electronic structure of the Ge-DB is markedly different from that of the Si-DB; the Ge-DB states does not position in the energy band gap of the Ge/GeO2 interface while the Si-DB states clearly appears. In addition, the charge density distribution of the Ge-DB state spreads more widely than that of the Si-DB state. These features are explained by considering the metallic properties of the bonding network of the Ge/GeO2 interface and the structural deformation of the Ge bulk at the Ge/GeO2 interface due to the lattice-constant mismatch.