NANOSCALE GATE INSULATOR FOR ORGANIC FIELD EFFECT TRANSISTOR APPLICATIONS

摘要

The High k thin films of ZrO_2 were deposited by electron beam evaporation for creating high capacitance devices. Capacitance as high as 0.2μF/cm~2 is obtained for the 80 nm thick ZrO_2 films that forms thickness equivalent of SiO_2 ～16nm (t_(eq)). Grazing incidence XRD confirmed crystalline tetragonal phase. Morphology of ZrO_2 films investigated using atomic force microscopy showed high roughness and pin holes that related to high leakage current. Whereas low leakage anodized Al nanogate insulator (t_(eq) of SiO_2 ～3.55 nm) were prepared varying the voltage and utilized as high capacitance gate oxide to realize low powered organic field effect transistor with polytriarylamine semiconductor. The observed threshold voltage is 0.35 V.