Fluorinated Metal-Oxide Thin-Film Transistors for Circuit Implementation on a Flexible Substrate


The effects of fluorination on amorphous indium-gallium-zinc oxide thin-film transistors and circuits fabricated on a polyimide flexible substrate were studied. Attributed to more effective passivation of donor-defects for a given thermal budget, fluorination resulted in suppressed apparent short-channel effects and better uniformity of turn-on voltage with reduced negative shift after laser lift-off from a glass carrier substrate. As representative digital circuits, 2-4 decoders were fabricated and characterized to demonstrate the advantages of incorporating fluorination in the construction of circuit building blocks, leading to higher gain, wider noise margins, more tightly distributed transition voltage and larger output swing.

Date of Publication: December 31, 2021
Electronic ISSN: 2768-167X
Publisher: IEEE

Runxiao Shi

Department of Electronic and Computer Engineering, the Hong Kong University of Science and Technology, Hong Kong (HKUST). (e-mail: rshiab@connect.ust.hk)

Sisi Wang

Department of Electronic and Computer Engineering, the Hong Kong University of Science and Technology, Hong Kong (HKUST).

Zhihe Xia

Department of Electronic and Computer Engineering, the Hong Kong University of Science and Technology, Hong Kong (HKUST).

Lei Lu

Department of Electronic and Computer Engineering, the Hong Kong University of Science and Technology, Hong Kong (HKUST) and School of Electronic and Computer Engineering, Peking University, Shenzhen, China.

Man Wong

Department of Electronic and Computer Engineering, the Hong Kong University of Science and Technology, Hong Kong (HKUST).


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