Mixed-Signal Organic Integrated Circuits in a Fully Photolithographic Dual Threshold Voltage Technology

Analog & digital circuits implemented in a dual threshold voltage (V_{T}) p-channel organic technology are presented. The dual V_{T} organic technology is compatible with large-area and mechanically flexible substrates due to its low processing temperature (\leq \hbox{95}\ ^{\circ}\hbox{C}) and scalable patterning techniques. We demonstrate the first analog & digital organic integrated circuits produced by a dual-gate metal process. The analog circuits are powered by a 5-V supply and include a differential amplifier and a two-stage uncompensated operational amplifier (op-amp). A dynamic comparator is measured to have an input offset voltage of 200 mV and latching time of 119 ms. Both the comparator and the op-amp dissipate 5 nW or less. Area-minimized digital logic is presented. Inverters powered by a 3-V supply were measured to have positive noise margins and consumed picowatts of power. An 11-stage ring oscillator, also powered by a 3-V supply, swings near rail to rail at 1.7 Hz. These results demonstrate dual threshold voltage process feasibility for large-area flexible mixed-signal organic integrated circuits.