Energetics and fs-dynamics at [100] surfaces of MOCVD-grown III-V semiconductors

MOCVD-preparation of ordered [100] surfaces of InP and GaP was monitored in-situ with reflectance difference/anisotropy spectroscopy (RDS/RAS). RDS was measured at 20 K after contamination-free transfer of the sample to UHV. Specific RD spectra with the highest peaks and fine structure were correlated with different ordered surface reconstructions. The ordered In-rich InP[100] surface was investigated with femtosecond 2PPE. Surface states and surface resonances near the /spl Gamma/-point showed up as peaks in the 2PPE spectrum in agreement with theoretical predictions.