Charge correction of the binding energy scale in XPS analysis of polymers using surface deposition of PDMS

A method is described for correcting the binding energy scale for specimen charging that occurs during XPS analysis of insulating samples. A small quantity of polymeric poly (dimethyl silicone) (PDMS) is deposited from solution onto the surface of a series of polymers. After XPS analysis, the binding energy scale is then adjusted to align the Si 2p signal of the adsorbed PDMS to the value observed on conducting samples. A model is proposed that shows that the binding energies of insulating specimens are measured with respect to the sample Fermi level. Using this method, the C 1s binding energy for aliphatic hydrocarbon (CH2)x in polyethylene is measured at 284.97 eV, in excellent agreement with previously reported values based on other correction schemes. Measured energies for 12 other materials are also presented. Copyright © 1999 John Wiley & Sons, Ltd.