Obiettivo The aim of this project is to use optical techniques (reflectance difference spectroscopy RDS or reflectance anisotropy spectroscopy RAS) to clarify some of the main unresolved problems of (001) semiconductor surfaces and in particular GaAs: spectroscopy of the clean surface, chemical and electronic passivation by sulfur or hydrogen atoms, adsorption of electropositive caesium or electronegative oxygen atoms, formation of surface barrier.The application of these techniques to investigate surface chemistry is a new concept. The main interest of this approach relies on: the simplicity of these optical techniques, which enables these results to be correlated with investigations of the electronic properties of the surface. Photoemission techniques do not easily permit this comparison due to the limited access time of current storage rings; the ability to operate on surfaces with defects or in ambient or liquid environments; and the expected strong sensitivity of these techniques to slight modifications of surface chemistry.The project will consist in: building of a UHV chamber adapted to the use of optical techniques in Saint Petersburg; transfer of technologies (UHV to Saint Petersburg, RAS to Rome); performing of a control experiment to test the UHV chamber, which will be built in St. Petersburg, and detailed analysis and comparison of the data obtained in similar experimental conditions in Palaiseau and Rome laboratories, using RAS as a bridge between the three groups. Programma(i) IC-INTAS - International Association for the promotion of cooperation with scientists from the independent states of the former Soviet Union (INTAS), 1993- Argomento(i) 15 - Condensed Matter Physics Invito a presentare proposte Data not available Meccanismo di finanziamento Data not available Coordinatore Ecole Polytechnique Contributo UE Nessun dato Indirizzo 91128 Palaiseau Francia Mostra sulla mappa Costo totale Nessun dato Partecipanti (2) Classifica in ordine alfabetico Classifica per Contributo UE Espandi tutto Riduci tutto Russian Academy of Sciences Russia Contributo UE Nessun dato Indirizzo 194021 St. Petersburg Mostra sulla mappa Costo totale Nessun dato Università degli Studi di Roma Tor Vergata Italia Contributo UE Nessun dato Indirizzo Via Orazio Raimondo 1 00173 Roma Mostra sulla mappa Costo totale Nessun dato