Abstract
The surface phonon dispersion curves and polarization vectors have been calculated for the (110) surfaces of nine Ill-V semiconductors. The results for GaAs are in generally good agreement with inelastic helium scattering and high-resolution electron energy loss spectroscopy measurements. We predict an additional acoustic branch along [ ]. For InP, we predict a prominent optical branch, in the gap between bulk acoustic and optical modes. The (110) surfaces of Ill-V semiconductors are the simplest of all semiconductor surfaces. Their atomic relaxations and electronic surface states are rather well understood. There have, however, been surprisingly few experimental studies of their vibrational properties, and ours in the first detailed theoretical interpretation. We find that the open, covalently-bonded structures of III-V semi-conductors lead to novel surface phonon branches that are not seen in more closepacked metallic and ionic structures. There are some parallels with SI(100) and Si(lll), but also differences because of the different surface geometries and the mass mismatch between cation and anion.
Das, Pradip Kumar (1994). Surface phonons of III-V semiconductors. Master's thesis, Texas A&M University. Available electronically from
https : / /hdl .handle .net /1969 .1 /ETD -TAMU -1994 -THESIS -D229.