Surface depth analysis for fluorinated block copolymer films by X-ray photoelectron spectroscopy using C60 cluster ion beam

X-ray photoelectron spectroscopy (XPS) using fullerene (C60) cluster ion bombardment was applied to films of a fluorinated block copolymer. Spectra so obtained were essentially different from those using Ar ion beam. Structure in the surface region with the depth down to 60 nm drawn on the basis of XPS with C60 beam was essentially the same as the one drawn by the result using dynamic secondary ion mass spectrometry, which is a well-established method for the depth analysis of polymers. This implies that XPS using C60 beam enables one to gain access to the depth analysis of structure in polymer films with the depth range over the analytical depth of conventional XPS, that is, three times inelastic mean-free path of photoelectrons.