Cellulose as biodegradable high-k dielectric layer in organic complementary inverters

We report on the natural source based and biodegradable material cellulose on Al2O3 as ultrathin hybrid high-k dielectric layer for applications in green electronics. Dielectric films of 16 nm cellulose (ε ≈ 8.4) and 8 nm Al2O3 (ε ≈ 9) exhibit low leakage currents up to electric fields of 1.5 MV/cm. Pentacene and C60 based organic thin film transistors show a well-balanced performance with operation voltages around 2 V. They are implemented in complementary inverters with excellent switching behavior, a small-signal gain up to 60 and with exceptionally high and balanced noise margin values of 82% at ultralow operation voltage (VDD = 2.5 V).