Controllable Shifts in Threshold Voltage of Top-Gate Polymer Field-Effect Transistors for Applications in Organic Nano Floating Gate Memory

Organic field-effect transistor (FET) memory is an emerging technology with the potential to realize light-weight, low-cost, flexible charge storage media. Here, solution-processed poly[9,9-dioctylfluorenyl-2,7-diyl]-co-(bithiophene)] (F8T2) nano floating gate memory (NFGM) with a top-gate/bottom-contact device configuration is reported. A reversible shift in the threshold voltage (V-Th) and reliable memory characterics was achieved by the incorporation of thin Au nanoparticles (NPs) as charge storage sites for negative charges (electrons) at the interface between polystyrene and cross-linked poly(4-vinylphenol). The F8T2 NFGM showed relatively high field-effect mobility (mu(FET)) (0.02 cm(2) V-1 s(-1)) for an amorphous semiconducting polymer with a large memory window (ca. 30 V), a high on/off ratio (more than 10(4)) during writing and erasing with an operation voltage of 80V of gate bias in a relatively short timescale (less than 1 s), and a retention time of a few hours. This top-gated polymer NFGM could be used as organic transistor memory element for organic flash memory.