Organic Pseudo-CMOS Circuits for Low-Voltage Large-Gain High-Speed Operation

Pseudo-CMOS inverters operating at 2 V and comprising four p-type organic transistors with ultrahigh gain are fabricated using self-assembled monolayer gate dielectrics. The inverter gain is as large as 302 at an operation voltage of 2 V, whereas the minimum operation voltage is as small as 0.5 V. The oscillation frequency of a five-stage ring oscillator comprising pseudo-CMOS inverters is 4.27 kHz at 2 V, corresponding to 23.4 mu s of propagation delay per stage. This is the fastest among organic circuits operating at low voltage. Pseudo-CMOS amplifier circuits show a large gain of 240 for a 3.0-mV input voltage.