Contribution a l'etude de l'effet de charge sur echantillon isolant en spectroscopie de photoelectrons (XPS)

Abstract

The accurate measurement of sample current for several non-conducting materials studied by XPS has proved that this effect is negligible and does not contribute to the surface potential determination. The influence of parameters of the sample (surface state, geometry, emission yield), those of the spectrometer (X-ray intensity, retarding potential), and the consequence of the use of a flood gun have been studied on simulated insulating samples starting from electrical characteristics and an exact value of the surface potential. Mechanisms are proposed to explain the different effects observed. The results show that electrical compensation of charge effect is difficult and that the energy scale linearity is affected on a retarding field spectrometer.