Flexible Low-Voltage Electric-Double-Layer TFTs Self-Assembled on Paper Substrates

Flexible low-voltage electric-double-layer (EDL) thin-film transistors (TFTs) with a patterned indium-tin-oxide (ITO) channel are self-assembled on paper substrates by only one shadow mask at room temperature. The operation voltage is 1.5 V when a microporous SiO
₂
solid electrolyte with large EDL capacitance is used as the gate dielectric. Such flexible TFTs operate in a full-depletion mode with a high mobility of 25.5 cm
²
/V · s, a low subthreshold swing of 0.16 V/decade, and a high current on/off ratio of 3 × 10
⁵
. The influence of mechanical bending to the electrical performance of the flexible EDL TFTs is investigated. A device simulator is used to simulate the electrical behavior, and a nice fitting to the experimental data is obtained.