Bending and stretching vibrations of hydrogen and deuterium at GaAs(110) surfaces

Abstract

Vibrations at hydrogen and deuterium covered GaAs(110) surfaces were investigated by high resolution electron energy loss spectroscopy. With semi-insulating crystals, bending modes of H and D were found at 515 and 387 cm −1 (63.9 and 48 meV), respectively. After large exposures when substrate bonds are broken scissor modes at 1000 cm −1 (124 meV) for AsH 2 and at 752 cm −1 (93.2 meV) for AsD 2 groups were observed. In the low-coverage regime two components of the GaH stretching vibration at 1830 and 1860 cm −1 (226.9 and 230.6 meV) were resolved. They may be explained by GaH dipole-dipole interactions.