Oxygen chemisorbed states and its electronic levels on (111) In2O3 surface: photoemission and photoconductivity studies

Abstract

The fundamentals of gas response mechanism of metal oxide conductometric sensors and in particularly for the In2O3-based ones as far remain in dispute. The difficulties in description of operation mechanism and the problems in this area are determined first of all by the lack of essential information concerning surface electronic levels modulated by environment (mainly by oxygen), which are responsible for surface conductivity changes. Are presented results provided by two different experimental methods on direct observations of such surface states originated from oxygen containing species adsorbed on In2O3. They are: synchrotron radiation photoemission spectroscopy (SRPES) and photoconductivity spectroscopy.