Design, properties, and TFT application of solution-processed In-Ga-Cd-O thin films

Concerning the revolutionary future of electronic devices, high-performance solution-processable semiconductors have earned increasing academic and industrial research interests. In this paper, we synthesize In-Ga-Cd-O semiconductor thin films via a solution method. Transparent amorphous/nanocrystalline oxide thin films with small surface roughness have been grown by controlling the relative ratio of Cd-content. The present thin-film transistor with an optimized Cd-ratio exhibits a saturation field-effect mobility up to 10 cm² V^-1 s^-1, an on/off current ratio of ∼1.3 x 10⁹, and a threshold voltage shift of ∼2.6 V under -5 V gate bias of 10 000 s, which are superior or comparable to those reported values of solution-processed conventional In-Ga-Zn-O counterparts. Our results indicate that the proposed In-Ga-Cd-O semiconductor would endow a promising transparent amorphous/nanocrystalline active material for electronic devices. (copyright 2018 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)