Electron transport in solids. impact on applications of electron spectroscopies

Abstract

Reliability of relations between photoelectron or Auger electron current leaving the solid and the concentration of atoms in the surface region determines the accuracy of quantitative analysis. It has been frequently demonstrated that the commonly accepted formalism is inadequate for certain systems or for certain experimental geometries. In particular, the usual assumptions simplifying the theoretical modal of electron transport in solids affect considerably the predicted depth of analysis and the predicted current of electrons leaving the solid. Simple measures to circumvent these effects are proposed. Realistic theoretical models of electron transport lead to the conclusion that the attenuation of electrons in solids may be, in general, nonexponential. Consequently, the current definitions of terms describing electron transport should be revised since they tacitly involve the assumption of exponential attenuation. These revisions are currently considered by the ASTM E-42 Committee.