XPS study during a soft and progressive sputtering of a monolayer on indium phosphide by argon cluster bombardment

Gas cluster ion beam is performed on an ultrathin polyphosphazene-like film grown on indium phosphide substrates to obtain crucial properties of this model system. Unlike standard sputtering technique using monoatomic ions, a gentle progressive digging of this subnanometric thick layer has been realized thanks to the unique depth profiling features of gas cluster ion beam. Furthermore, our results highlight the properties of the electrochemically formed film made of phosphorus-nitrogen electron-rich chemical bond creating a strong attenuation of the photoelectron underneath. Such approach opens exciting insights in the chemical and physical analysis of sensitive surfaces as ultrathin covering layers.