Polymer-Doped Ink System for Threshold Voltage Modulation in Printed Metal Oxide Thin Film Transistors

Zhennan Zhu; Jianhua Zhang; Yiping Wang; Honglong Ning; Dong Guo; Wei Cai; Shangxiong Zhou; Zhihao Liang; Rihui Yao; Junbiao Peng

doi:10.1021/acs.jpclett.9b01206

Polymer-Doped Ink System for Threshold Voltage Modulation in Printed Metal Oxide Thin Film Transistors

J Phys Chem Lett. 2019 Jun 20;10(12):3415-3419. doi: 10.1021/acs.jpclett.9b01206. Epub 2019 Jun 7.

Authors

Affiliations

¹ Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China.
² Key Laboratory of Advanced Display and System Applications of Ministry of Education , Shanghai University , Shanghai 200072 , China.
³ State Key Laboratory of Mechanics and Control of Mechanical Structures , Nanjing University of Aeronautics and Astronautics , Nanjing 210016 , China.
⁴ School of Materials Science and Engineering , Beihang University , Beijing 100191 , China.

PMID: 31181931
DOI: 10.1021/acs.jpclett.9b01206

Abstract

A polymer-doped ink system was applied to a printed InO _x thin film transistor (TFT), and enhancement mode devices were obtained with an appropriate polymer doping amount. As the polymer doping concentration (PDC) increases, the threshold voltage of thin film transistor shifts positively, while the mobility and subthreshold slope show only an insignificant degradation. The microanalysis shows that the polymer doping can generate traps and defects in the oxide lattice, thus shifting the threshold voltage positively and degrading the mobility and subthreshold slope. Meanwhile, the doping can also facilitate the formation of an oxide lattice in the local region, which counterbalances the effect of doping on the mobility and subthreshold slope. The InO _x, the TFT shows good electrical performance at an optimal PDC of 0.3 wt %, with a mobility of 4.2 cm² V^-1 s^-1, a threshold voltage of 0.7 V, an on/off ratio of 10⁶, and a subthreshold slope of 0.30 V/dec.