Ultraviolet light-densified oxide-organic self-assembled dielectrics: Processing thin-film transistors at room temperature

Low-temperature, solution-processable, high-capacitance, and low-leakage gate dielectrics are of great interest for unconventional electronics. Here, we report a near room temperature ultraviolet densification (UVD) methodology for realizing high-performance organic-inorganic zirconia self-assembled nanodielectrics (UVD-ZrSANDs). These UVD-ZrSAND multilayers are grown from solution in ambient, densified by UV radiation, and characterized by X-ray reflectivity, atomic force microscopy, X-ray photoelectron spectroscopy, and capacitance measurements. The resulting UVD-ZrSAND films exhibit large capacitances of >700 nF/cm2 and low leakage current densities of <10-7 A/cm2, which rival or exceed those synthesized by traditional thermal methods. Both the p-type organic semiconductor pentacene and the n-type metal oxide semiconductor In2O3 were used to investigate UVD-ZrSANDs as the gate dielectric in thin-film transistors, affording mobilities of 0.58 and 26.21 cm2/(V s), respectively, at a low gate voltage of 2 V. These results represent a significant advance in fabricating ultra-thin high-performance dielectrics near room temperature and should facilitate their integration into diverse electronic technologies.