Facile encapsulation of oxide based thin film transistors by atomic layer deposition based on ozone

Abstract

A simplified encapsulation strategy for metal-oxide based TFTs, using ozone instead of water as an oxygen source in a low-temperature ALD process is demonstrated. Thereby, the threshold voltage remains unaltered and the hysteresis is permanently reduced. Costly energy- and time-consuming post-treatment processes can be avoided. This concept is widely applicable to various encapsulation materials (e.g., Al2 O3 , TiO2 , ZrO2 ) and metal-oxide channel semiconductors (e.g., zinc-tin-oxide (ZTO), indium-gallium-zinc-oxide (IGZO)).