Low-Voltage Transparent Indium-Zinc-Oxide Coplanar Homojunction TFTs Self-Assembled on Inorganic Proton Conductors

H(3)PO(4)-incorporated nanocolumnar SiO(2)-based proton conductors show an enhanced electric double layer (EDL) capacitance value of similar to 8 mu F/cm(2) at 20 Hz. The upper frequency limit of EDL formation is found to be higher than 10 kHz. Transparent indium-zinc-oxide (IZO) coplanar homojunction thin-film transistors gated by such proton conductors are fabricated by one metal shadow mask self-assembled method. The operating voltage is found to be as low as 0.6 V. The current ON/OFF ratio, the subthreshold swing, and field-effect mobility are estimated to be 6 x 10(5), 68 mV/dec, and 12 cm(2)/V.s, respectively. Such transparent transistors hold promise for low-cost and portable electrochromic devices and invisible biochemical sensors.