First-principles electronic-structure calculation of dangling bonds at Si/SiO$_2$ and Ge/GeO$_2$ interfaces

Tomoya Ono; Shoichiro Saito

paper

First-principles electronic-structure calculation of dangling bonds at Si/SiO $_{2}$ and Ge/GeO $_{2}$ interfaces

arXiv:0911.5608

Abstract

Evidence of the absence of the clear electron spin-resonance signal from Ge dangling bonds (DBs) at Ge/GeO $_{2}$ interfaces is explored by means of first-principles electronic-structure calculations. Comparing the electronic structures of the DBs at Si/SiO $_{2}$ and Ge/GeO $_{2}$ 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/GeO $_{2}$ 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/GeO $_{2}$ interface and the structural deformation of the Ge bulk at the Ge/GeO $_{2}$ interface due to the lattice-constant mismatch.

12 pages

First-principles electronic-structure calculation of dangling bonds at Si/SiO2​ and Ge/GeO2​ interfaces

Abstract

First-principles electronic-structure calculation of dangling bonds at Si/SiO $_{2}$ and Ge/GeO $_{2}$ interfaces