Ultra-thin silver oxide /silver transparent anodes for high-efficiency organic light-emitting devices

Abstract

An ultra-thin silver oxide/silver film simultaneously having excellent electrical conductivity and optical transmittance was realized by introducing a silver oxide seed layer on a glass substrate. A silver oxide, achieved by conducting an ultraviolet-ozone treatment on the thermally deposited 1-nm-thick Ag film, improved the wetting ability of the subsequently deposited Ag atoms and suppressed their random migration. The ultra-thin silver films using silver oxide seed layers exhibited unique virtues of low sheet resistance, superior surface morphology, and slight optical loss. A high-efficiency phosphorescent organic light-emitting device employing the prepared ultra-thin silver transparent anode was fabricated, with about 1.4 times power efficiency relative to its ITO-based counterpart. Significantly, the ultra-thin silver film was also adopted to realize a flexible device based on a PET substrate, which indicated its great potential in flexible devices. The results demonstrated that the ultra-thin silver film based on the silver oxide seed layer is a promising alternative to ITO.