Fully‐Solution‐Processed Enhancement‐Mode Complementary Metal‐Oxide‐Semiconductor Carbon Nanotube Thin Film Transistors Based on BiI3‐Doped Crosslinked Poly(4‐Vinylphenol) Dielectrics for Ultralow‐Power Flexible Electronics

Abstract

AbstractThe threshold voltage (Vth) adjustment of complementary metal‐oxide‐semiconductor (CMOS) thin film transistors (TFTs) is one of the research hotspots due to its key role in energy consumption control of CMOS circuits. Here, ultralow‐power flexible CMOS circuits based on well‐matched enhancement‐mode (E‐mode) CMOS single‐walled carbon nanotube (SWCNT) TFTs are successfully achieved through tuning the work function of gate electrodes, electron doping, and printing techniques. E‐mode P‐type CMOS SWCNT TFTs with the full‐solution procedure are first obtained through decreasing the work function of Ag gate electrodes directly caused by the deposition of bismuth iodide (BiI3)‐doped solid‐state electrolyte dielectrics. After synthetic optimization of dielectric compositions and semiconductor printing process, the flexible printed E‐mode SWCNT TFTs show the high Ion/Ioff ratios of ≈106, small subthreshold swing (SS) of 70–85 mV dec−1, low operating voltages of ≈0.5 to −1.5 V, good stability and excellent mechanical flexibility during 10 000 bending cycles. E‐mode N‐type SWCNT TFTs are then selectively achieved via printing the polarity conversion ink (2‐Amino‐2‐methyl‐1‐propanol (AMP)  as electron  doping agent) in P‐ type TFT channels. Last, printed SWCNT CMOS inverters are successfully constructed with full rail‐to‐rail output characteristics and the record unit static power consumption of 6.75 fW µm−1 at VDD of 0.2 V.