Polymers electron inelastic mean free path

XPS may be used to non-destructively depth profile a surface. This is an important ability since the most common depth profiling method used in surface techniques is acheived by sputtering surface atoms from the material with the use of a high flux ion gun, such an approach w ould be inappropriate for analysing polymers due to the extreme levels of damage w hich would occmr The surface sensitivity of XPS derives from the low inelastic mean free path of electrons in solids. This means that photoelectrons emitted from deep in the sample have a very small probability of... 

---