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Amorphous In-Ga-Zn-O (IGZO) is a high-mobility semiconductor employed in modern thin-film transistors for displays and it is considered as a promising material for Schottky diode-based rectifiers. Properties of the electronic components based on IGZO strongly depend on the manufacturing parameters such as the oxygen partial pressure during IGZO sputtering and post-deposition thermal annealing. In this study, we investigate the combined effect of sputtering conditions of amorphous IGZO (In:Ga:Zn=1:1:1) and postdeposition thermal annealing on the properties of vertical thin-film Pt-IGZO-Cu Schottky diodes, and evaluated the applicability of the fabricated Schottky diodes for low-frequency half-wave rectifier circuits. The change of the oxygen content in the gas mixture from 1.64% to 6.25%, and post-deposition annealing is shown to increase the current rectification ratio from 10 5 to 10 7 at ±1 V, Schottky barrier height from 0.64 eV to 0.75 eV, and the ideality factor from 1.11 to 1.39. Half-wave rectifier circuits based on the fabricated Schottky diodes were simulated using parameters extracted from measured current-voltage and capacitancevoltage characteristics. The half-wave rectifier circuits were realized at 100 kHz and 300 kHz on as-fabricated Schottky diodes with active area of 200 μm × 200 μm, which is relevant for the near-field communication (125 kHz-134 kHz), and provided the output voltage amplitude of 0.87 V for 2 V supply voltage. The simulation results matched with the measurement data, verifying the model accuracy for circuit level simulation. INDEX TERMS amorphous In-Ga-Zn-O, capacitance-voltage characteristics, currentvoltage characteristics, half-wave rectifiers, Schottky diodes, sputtering

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The fabrication of solution-processed electronic devices based on amorphous In–Ga–Zn–O (a-IGZO) requires high-temperature post-deposition annealing to activate IGZO layers and minimize impurities. Deep-ultraviolet (DUV) treatment can reduce the post-deposition annealing temperature when manufacturing a-IGZO thin-film transistors. Here, we investigate the effect of thermal annealing and DUV treatment in a nitrogen and ozone atmosphere on the properties of vertical thin-film Pt–IGZO–Cu Schottky diodes based on spin-coated a-IGZO. The DUV treatment in nitrogen allowed reducing the process temperature to 200 °C. A defect-induced hysteresis was observed on the current–voltage characteristics of as-fabricated Schottky diodes. The values of rectification ratio and barrier height were higher and the values of ideality factor were lower upon the backward bias sweep. It is assumed that the hysteresis behavior is caused by the presence of trap states in the semiconductor layer or at the Schottky interface. A trap density of 108 cm−2 to 1011 cm−2 was deduced from the current–voltage characteristics. The defect-induced hysteresis effect could be suppressed by depositing an Al2O3 layer and applying an additional thermal treatment of the whole diode structure.