Monochromatic light-assisted erasing effects of In-Ga-Zn-O thin film transistor memory with Al2O3/Zn-doped Al2O3/Al2O3 stacks

We studied how electrical erasing of indium gallium zinc oxide-thin-film-transistor memory was improved by adding concurrent irradiation with monochromatic light (ML). At fixed gate bias, irradiating at wavelengths of <= 500 nm increased the erasing window (Delta Vth-e) significantly: At a gate bias of -20V and an erasing time of 5 min, ML irradiation at 400nm increased Delta Vth-e from 0.29 to 3.21 V. Delta Vth-e increased incrementally with gate bias, erasing time, and ML power density, particularly at short ML wavelengths. Analyzing our experimental results, we discuss the underlying erasure mechanisms. (C) 2014 AIP Publishing LLC.