Enhanced Performance of Organic Field-Effect Transistor with Bi-Functional N-Type Organic Semiconductor Layer

Organic field-effect transistors (OFETs) hold great promise for applications in non-volatile memories, detectors, and artificial synapses due to the good flexibility and biocompatibility. However, certain drawbacks such as high operating voltages and significant degradation in endurance characteristics have hindered their practical implementations. Herein, a novel approach is proposed to enhance the performance of OFETs by incorporating a bi-functional n-type polymer semiconductor interlayer, Poly-{[N,N'-bis(2-octyldodecyl)naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5 '-(2,2 '-bithiophene)} (N2200), into a pentacene OFET structure. The device exhibits remarkable improvements, with reliable P/E operation cycles of over than 104 and a retention time of more than 10 years. On one hand, the inclusion of N2200 as an n-type semiconductor effectively reduces the height of hole-injection barrier for trapping and thus reducing the working voltage based on the electrostatic induction theory. On the other hand, n-type semiconductor N2200 serves as a native hole-consumption (or hole-trapping) dielectric, and its narrower bandgap restrains the formation of deep hole-traps, thus favoring the endurance characteristics of the OFET. A novel approach is proposed to enhance the performance of pentacene OFET memory device by incorporating a bi-functional n-type polymer semiconductor interlayer (N2200). The device exhibits a memory window of larger than 13.7 V at P/E voltages (+/- 20 V), reliable P/E operation cycles of over than 104 and a retention time of more than 10 years.image