Combined Argon cluster UPS-XPS depth profile of OLED thin-film

Low-energy argon cluster ions were used to depth profile through an organoelectronic (TCTA) thin-film deposited on ITO. XPS and UPS spectra were acquired after each etching cycle. Compositional changes were seen through the film and at the interface with the substrate. Changes in UPS spectra were directly compared to changes in compositional change.