Improvements of Electrical Characteristics in Poly-Si Nanowires Thin-Film Transistors with External Connection of a BiFeO3 Capacitor

Tsung-Kuei Kang; Yu-Yu Lin; Han-Wen Liu; Che-Li Lin; Po-Jui Chang; Ming-Cheng Kao; Hone-Zern Chen

doi:10.3390/membranes11100758

Improvements of Electrical Characteristics in Poly-Si Nanowires Thin-Film Transistors with External Connection of a BiFeO₃ Capacitor

Membranes (Basel). 2021 Sep 30;11(10):758. doi: 10.3390/membranes11100758.

Authors

Tsung-Kuei Kang¹, Yu-Yu Lin¹, Han-Wen Liu², Che-Li Lin¹, Po-Jui Chang², Ming-Cheng Kao³, Hone-Zern Chen³

Affiliations

¹ Department of Electronic Engineering, Feng Chia University, Taichung 407, Taiwan.
² Department of Electrical Engineering, National Chung Hsing University, Taichung 407, Taiwan.
³ Department of Electrical Engineering, Hsiuping University of Science and Technology, Taichung 407, Taiwan.

Abstract

By a sol-gel method, a BiFeO₃ (BFO) capacitor is fabricated and connected with the control thin film transistor (TFT). Compared with a control thin-film transistor, the proposed BFO TFT achieves 56% drive current enhancement and 7-28% subthreshold swing (SS) reduction. Moreover, the effect of the proposed BiFeO₃ capacitor on I_DS-V_GS hysteresis in the BFO TFT is 0.1-0.2 V. Because dV_int/dV_GS > 1 is obtained at a wide range of V_GS, it reveals that the incomplete dipole flipping is a major mechanism to obtain improved SS and a small hysteresis effect in the BFO TFT. Experimental results indicate that sol-gel BFO TFT is a potential candidate for digital application.

Keywords: BiFeO3 capacitor; drive current; hysteresis; incomplete dipole flipping; sol–gel method; subthreshold swing.

Grants and funding

MOST.108-2221-E-035 -040/the Ministry of Science and Technology of Taiwan