Write-once memory effects observed in Ga-doped ZnO/organic semiconductor/MoO3/Au structures

Abstract

Electrical switching phenomena in a device configuration of inverted organic light-emitting diodes have been observed. The device structure was Ga-doped ZnO (GZO)/N,N′-dicarbazolyl-3,5-benzene (m-CP)/MoO3 (10 nm)/Au (50 nm) fabricated by solution coating. The devices are write-once-read-many-times (WORM) memory devices with low switching voltage (<3 V) and long retention time (>700 h). Equivalent circuits in OFF and ON states are determined from the Cole–Cole plots measured by impedance spectroscopy. The switching phenomena and nonvolatile memory behavior are attributable to the formation conductive Au filaments in the m-CP layer of the ON state.