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We report on the fabrication of ZnO-channel charge injection memory thin-film transistors (TFTs). Our non-volatile memory TFT has a thin pentacene on top of a dielectric sandwich which has 3 nm-thin inserted potential well as a hole trap layer. The thin pentacene in contact with Au top electrode supports effective hole injection from pentacene into the inserted well under +8 V programming gate pulse while those injected holes are effectively ejected out under −8 V pulse, so that ZnO channel below the dielectric may have two different current states: write and erase. Our device operates at less than 2 V and shows a retention time of about 1000 s after programmed at +8 V, along with an effective program/erase ratio of 5–20.

We report on the fabrication of pentacene-based thin-film transistors (TFTs) with a 230 nm-thick double polymer dielectric composed of 30 nm-thin low- k poly-4-vinyphenol (PVP) and 200 nm-thick high- k poly(vinylidene fluoride/trifluoroethylene) [P(VDF–TrFE)] dielectric on polyethersulfone (PES) films. Our 230 nm-thick double (high- k /low- k ) polymer showed a good dielectric strength of ∼2 MV/cm, a high capacitance of 26 nF/cm 2 with k = ∼7. Based on this double polymer dielectric, our flexible pentacene TFT displayed a high saturation mobility of 1.22 cm 2 /V s, a threshold voltage of −2.5 V, and on/off ratio of 10 3 , stably operating under −5 V.

We report a low-temperature fabrication of mixed-organic–inorganic nanohybrid superlattices for high-k thin stable gate dielectrics on flexible substrates. The self-assembled organic layers (SAOLs) were grown by repeated sequential adsorptions of C C-terminated alkylsilane and metal (Al or Ti) hydroxyl with ozone activation, which was called “molecular layer deposition (MLD)”. The MLD method is a self-controlled layer-by-layer growth process under vacuum conditions, and is perfectly compatible with the atomic layer deposition (ALD) method. The TiO2 and Al2O3 inorganic layers were grown by ALD, which relies on sequential saturated surface reactions resulting in the formation of a monolayer in each sequence and is a potentially powerful method for preparing high quality multicomponent superlattices. The MLD method combined with ALD (MLD–ALD) was applied to fabricate SAOLs-Al2O3–SAOLs-TiO2 nanohybrid superlattices on polycarbonate substrates with accurate control of film thickness, large-scale uniformity, excellent conformality, good reproducibility, multilayer processing capability, sharp interfaces, and excellent film qualities at relatively low temperature. The prepared ultrathin nanohybrid films exhibited good thermal and mechanical stability, good flexibility, excellent insulating properties, and relatively high dielectric constant k (6–11). The MLD–ALD method is an ideal fabrication technique for various flexible electronic devices.