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Ferroelectric organic field-effect transistor nonvolatile memories (Fe-OFET-NVMs) offer attractive features for future memory applications, such as flexible and wearable electronics. Polymer semiconductor-based top-gate Fe-OFET-NVMs possess natural advantages in the device structure and processing manufacturing, compared to small-molecule semiconductor-based bottom-gate Fe-OFET-NVMs. However, their performances, such as mobility and operating voltages, should be further improved to be comparable to those of the latter. In this Letter, we develop a route to achieve high-performance top-gate Fe-OFET-NVMs, by employing a polymer semiconductor channel and self-organized ferroelectric/dielectric gate insulators, which were processed by a solution spin-coating technique. The optimal Fe-OFET-NVM exhibits a high mobility of 1.96 cm2/V s on average, a reliable endurance over 400 cycles, a stable retention capability over 6 × 104 s, and a life more than one year. Furthermore, the operating voltage of the Fe-OFET-NVM is reduced to ±20 V by scaling down the thickness of the ferroelectric/dielectric gate insulator. The whole performances of our memories are comparable to or better than those of the previous Fe-OFET-NVMs. [ABSTRACT FROM AUTHOR]

Flexible floating-gate structural organic thin-film transistor (FG-OTFT) nonvolatile memories (NVMs) are demonstrated based on an integrated molecular floating-gate/tunneling (I-FG/T) layer and a pn-heterojunction channel layer. Semiconducting polymer poly(9,9-dioctylfluorene-co-benzothiadiazole) nanoparticles and insulating polymer polystyrene are used to build the I-FG/T layers by spin-coating their solution. The dependence of the memory performances on the structure of I-FG/T layers is researched. For achieving a large charge storage capacity, the pn-heterojunction channel, consisting of 2,9-didecyldinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene and F16CuPc, is fabricated to provide both electrons and holes for injecting and trapping in the floating gate by overwriting the stored charges with an opposite polarity at the programming and erasing voltages, respectively. As an optimal result, a high performance flexible FG-OTFT NVM is achieved, with a large memory window of 21.6 V on average, a highly stable charge storage retention capability up to 10 years, and a highly reliable programming/erasing switching endurance over 200 cycles. The FG-OTFT NVM also exhibits an excellent mechanical bending durability with the memory performances maintaining well over 6000 bending cycles at a bending radius of 5.9 mm. [ABSTRACT FROM AUTHOR]