Enhanced Stability and Mobility of Solution-Processed Oxide Thin-Film Transistors with Bilayer Terbium-incorporated Indium Oxide Channel

He, Penghui [Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education& International Science and Technology Innovation Cooperation Base for Advanced Display Technologies of Hunan Province, School of Physics and Electronics, Hunan University, Changsha 410082, China] Ding, Chunchun [State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Semiconductors (College of Integrated Circuits) Hunan University, Changsha 410082, China] Li, Guoli [UCL] Hu, Wei [Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education& International Science and Technology Innovation Cooperation Base for Advanced Display Technologies of Hunan Province, School of Physics and Electronics, Hunan University, Changsha 410082, China] Ma, Chao [School of Materials Science and Engineering, Hunan University, Changsha 410082, China] Flandre, Denis [UCL] Iñíguez, Benjamín [Departament d’Enginyeria Electrònica, Elèctrica i Automàtica, Universitat Rovira i Virgili, 43007 Tarragona, Spain] Liao, Lei [Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education& International Science and Technology Innovation Cooperation Base for Advanced Display Technologies of Hunan Province, School of Physics and Electronics, Hunan University, Changsha 410082, China] Lan, Lingfeng [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, China] Liu, Xingqiang [Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education& International Science and Technology Innovation Cooperation Base for Advanced Display Technologies of Hunan Province, School of Physics and Electronics, Hunan University, Changsha 410082, China] et al.[show all]

The trade-off between mobility and stability in oxide thin-film transistors (TFTs) hinders further advances of active-matrix flat panel display. Herein, a solution-processed bilayer active channel is designed to improve the stability and mobility simultaneously. The optical bandgap and work function of Tb:In2O3 films are modulated by tuning the films thickness and Tb concentration of Tb-doped indium oxide (Tb:In2O3) films. Large conduction band offset is achieved in Tb:In2O3 bilayer channel, which induces accumulation of abundant electrons at the interface. The mobility is significantly improved to 38.2 cm2/Vs, and the photoinduced stability of bilayer Tb:In2O3 TFTs is improved with low threshold voltage shift of 0.26 V and −0.38 V under negative-bias illumination stress (NBIS) and negative-bias temperature illumination stress (NBTIS), respectively.