Influence of Post-UV/Ozone Treatment of Ultrasonic-Sprayed Zirconium Oxide Dielectric Films for a Low-Temperature Oxide Thin Film Transistor

Abstract

Solution-processed metal oxides require a great deal of thermal budget in order to achieve the desired film properties. Here, we show that the deposition temperature of sprayed zirconium oxide (ZrOx) thin film can be lowered by exposing the film surface to an ultraviolet (UV) ozone treatment at room temperature. Atomic force microscopy reveals a smooth and uniform film with the root mean square roughness reduced from ~ 0.63 nm (UVO-O) to ~ 0.28 nm (UVO-120) in the UV–ozone treated ZrOx films. X-ray photoelectron spectroscopy analysis indicates the formation of a Zr–O network on the surface film, and oxygen vacancy is reduced in the ZrOx lattice by increasing the UV–ozone treatment time. The leakage current density in Al/ZrOx/p-Si structure was reduced by three orders of magnitude by increasing the UV-ozone exposure time, while the capacitance was in the range 290–266 nF/cm2, corresponding to a relative permittivity (k) in the range 5.8–6.6 at 1 kHz. An indium gallium zinc oxide (IGZO)-based thin film transistor, employing a UV-treated ZrOx gate dielectric deposited at 200 °C, exhibits negligible hysteresis, an Ion/Ioff ratio of 104, a saturation mobility of 8.4 cm2 V−1S−1, a subthreshold slope of 0.21 V.dec−1, and a Von of 0.02 V. These results demonstrate the potentiality of low-temperature sprayed amorphous ZrOx to be applied as a dielectric in flexible and low-power-consumption oxide electronics.

Tuneable Functionalization of Glass Fibre Membranes with ZnO/SnO2 Heterostructures for Photocatalytic Water Treatment: Effect of SnO2 Coverage Rate on the Photocatalytic Degradation of Organics

“…In order to remove defects like oxygen vacancies or chlorine, as-prepared ZnO/SnO 2 membranes have been cleaned under a UV/ozone atmosphere (254 nm, 20 W) for 30 min. Compared to plasma or thermal post-treatments, the dry UV/ozone (also called UVO, for ultra-violet ozone) post-treatment has been favoured for its ability to generate, at room temperature, clean and well-oxidised metal oxide structures with very low impact on their morphologies [50]. Also, this technique is known for being able to effectively remove chlorine defects from SnO 2 structures [51].…”

Effects of Structural Phase Transitions on Hysteresis in Air‐Processed Organic–Inorganic Halide Perovskite Thin‐Film Transistors

“…The AlO x solution was prepared by dissolving aluminum chloride (AlCl 3 ) in acetonitrile (35%) and ethylene glycol (65%) (0. [77,78] After forming contact holes by dry etching, we sputter deposited a 60 nm-thick IZO layer at room temperature and patterned it by wet etching to form source and drain electrodes. On top of the source and drain electrodes, we spin-coated a 1.3 μm-thick layer of positive photoresist (PR) (Merck Korea Ltd.) layer and patterned it to form "banks" for the perovskite semiconductor (MAPbI 3 ).…”

Reduction of Hysteresis in Hybrid Perovskite Transistors by Solvent-Controlled Growth

“…During treatment, the 185 nm UV light decomposed atmospheric oxygen molecules (O 2 ) to oxygen-free radicals (·O), which effectively performed oxidative treatments on the surface of the Al 2 O 3 . The O can react with O 2 to form ozone (O 3 ), which decomposes back to ·O and O 2 due to the presence of the 254 nm UV light [ 33 , 34 , 35 ]. These reactive ·O radicals are highly effective at removing organic residuals from metal oxide film surfaces, increasing the metal-oxygen bonds, and reducing oxygen-related defects.…”

“…These reactive ·O radicals are highly effective at removing organic residuals from metal oxide film surfaces, increasing the metal-oxygen bonds, and reducing oxygen-related defects. UV treatment thus results in a smooth surface morphology with less defects [ 33 , 34 , 35 ].…”