Fig. 1. (Color online) (a) A schematic cross-section of an IGZO or IGZO:F TFT. (b) Comparison of the measured transfer characteristics of IGZO:F and IGZO TFTs with W = 10 µm and L decreasing from 50 to 2 µm. (c) Comparison of the measured transfer characteristics of IGZO:F and IGZO TFTs before and after LLO. (d) Measured statistical distributions of the VON of IGZO:F and IGZO TFTs before and after LLO^[17]. Copyright 2021 IEEE.

Fig. 2. (Color online) The fabrication process of SG and DG ITZO TFTs.

Fig. 3. (Color online) Transfer characteristics of (a) SG TFTs, (b) DG TFTs with BG as the MG and TG as the OG, and (c) DG TFTs with TG as the MG and BG as the OG; extracted VTH of (d) SG TFTs, (e) DG TFTs with BG as the MG and TG as the OG, and (f) DG TFTs with TG as the MG and BG as the OG.

Fig. 4. (Color online) Fluorination-enhanced 2-4 decoder^[17]. (a) Gate-level schematic and truth table of a 2-4 decoder. (b) TFT-level circuit diagram and truth table of an INV. (c) TFT-level circuit diagram and truth table of a NOR. (d) A photograph of a fabricated 2-4 decoder on PI. (e) Measured VTCs of 2-4 decoders fabricated using IGZO:F TFTs. (f) Measured VTCs of 2-4 decoders fabricated using IGZO TFTs. (g) Simulated VTCs of ideal implementation with the same VON ~ 0 V for all TFTs. (h) Implementation with VON shifts of −4 V for both TFT T8 of the NOR0 gate and the pull-down TFT T6 of the NOR1 gate^[17]. Copyright 2021 IEEE.

Fig. 5. (Color online) An AFE system for the acquisition of bio-potential signals. (a) System architecture. (b) PI carrying AFE systems placed on the thenar muscle of a hand. In-vitro measurements of (c) EMG and (d) ECG^[21]. Copyright 2023 Wiley.

Fig. 6. (Color online) DG ITZO TFT-based in-pixel amplifiers w/ and w/o provision for compensation of TFT parameter variation: (a) circuit schematic and (b) timing diagram; (c) distribution of MG voltage VB for 40 pixel circuits w/ and w/o compensation; (d) dependance of AV on VI and (e) distribution of AV at VI=0 V for 40 amplifiers w/o compensation. In-pixel amplifiers w/ provision for compensation of TFT parameter variation: (f) circuit schematic and (g) timing diagram; (h) microscope image of a tactile pixel and (i) photograph of a 16 ×16 active-matrix tactile sensor array; (j) dependance of AV on VI and (k) distribution of AV at VI=0 V for 40 amplifiers w/ compensation^[22]. Copyright 2023 IEEE.

Fig. 7. (Color online) MG voltage VB distribution over a 16 ×16 tactile sensor array (a) w/o and (b) w/ compensation^[22]; tactile images from arrays (c) w/o and (d) w/ compensation when loaded with a letter stamp “O”; (e) tactile images acquired from an 8 × 8 tactile sensor array^[23]. Copyright 2022 and 2023 IEEE.

Fig. 8. (Color online) A schematic system diagram of a more capable bio-potential acquisition system on a flexible substrate.

Fig. 9. (Color online) Flexible tactile sensor array integrated with an artificial neural network as a bionic “smart” system.