Mechanism for the increase of indium-tin-oxide work function by O-2 inductively coupled plasma treatment

Abstract

The effects of O-2 inductively coupled plasma (ICP) treatment on the chemical composition and work function of indium-tin-oxide (ITO) surface were investigated. Synchrotron radiation photoemission spectroscopy showed that the O-2 ICP treatment resulted in the increase of the ITO work function by 0.8 eV. Incorporation of oxygen atoms near the ITO surface during the ICP treatment induced a peroxidic ITO surface, increasing the work function. The enhanced oxidation of a thin Ni overlayer on the O-2-ICP-treated sample suggests that preventing the migration of oxygen atoms into the active region of organic light-emitting diodes is important for improving device lifetime. (C) 2004 American Institute of Physics.