May, M.M.; Supplie, O.; Höhn, C.; Zabka, W.-D.; Lewerenz, H.-J.; van de Krol, R.; Hannappel, T.: Water-induced modifications of GaP(100) and InP(100) surfaces studied by photoelectron spectroscopy and reflection anisotropy spectroscopy. In: Kanai, Y. [u.a.] [Eds.] : Solar Hydrogen and Nanotechnology VIII. San Diego, California, United States, August 25, 2013 . Bellingham, Wash.: SPIE, 2013 (Proceedings of SPIE ; 8822), p. 88220M/1-7
10.1117/12.2026172
Open Access Version

Abstract:
In this work, we investigate the initial interaction of water and oxygen with different surface reconstructions of GaP(100) applying photoelectron spectroscopy, low-energy electron diffraction, and reflection anisotropy spectroscopy. Surfaces were prepared by metal-organic vapour phase epitaxy, transferred to ultra-high vacuum, and exposed to oxygen or water vapour at room temperature. The (2 × 4) reconstructed, Ga-rich surface is more sensitive and reactive to adsorption, bearing a less ordered surface reconstruction upon exposure and indicating a mixture of dissociative and molecular water adsorption. The p(2 × 2)/c(4 × 2) P-rich surface, on the other hand, is less reactive, but shows a new surface symmetry after water adsorption. Correlating findings of photoelectron spectroscopy with reflection anisotropy spectroscopy could pave the way towards optical in-situ monitoring of electrochemical surface modifications with reflection anisotropy spectroscopy.