In this study, molybdenum tungsten/amorphous InGaZnO (a-IGZO)/TiO2/n-type Si-based resistive random access memory (ReRAM) is manufactured. After deposition of the a-IGZO, annealing was performed at 200, 300, 400, and 500 °C for approximately 1 h in order to analyze the effect of temperature change on the ReRAM after post annealing in a furnace. As a result of measuring the current-voltage curve, the a-IGZO/TiO2-based ReRAM annealed at 400 °C reached compliance current in a low-resistance state, and showed the most complete hysteresis curve. In the a-IGZO layer annealed at 400 °C, the O1/Ototal value increased most significantly, to approximately 78.2%, and the O3/Ototal value decreased the most, to approximately 2.6%. As a result, the a-IGZO/TiO2-based ReRAM annealed at 400 °C reduced conductivity and prevented an increase in leakage current caused by oxygen vacancies with sufficient recovery of the metal-oxygen bond. Scanning electron microscopy analysis revealed that the a-IGZO surface showed hillocks at a high post annealing temperature of 500 °C, which greatly increased the surface roughness and caused the surface area performance to deteriorate. Finally, as a result of measuring the capacitance-voltage curve in the a-IGZO/TiO2-based ReRAM in the range of −2 V to 4 V, the accumulation capacitance value of the ReRAM annealed at 400 °C increased most in a nonvolatile behavior.

Solution-processed In-Zn oxide (IZO) semiconductor thin-film transistors (TFTs) were fabricated with passivation layers of either poly(methyl methacrylate) (PMMA) or cyclic transparent optical polymer (CYTOP). According to the transfer curves obtained on the day of fabrication and after 200 days, the drain-source current of the IZO TFT without a passivation layer decreased by approximately 37 %. For the PMMA-passivated IZO TFT, it decreased by approximately 31 %. The current for the CYTOPpassivated IZO TFT showed significantly lower, only 7 % deterioration. Hence, the CYTOP-passivated IZO TFT exhibited improved electrical stability under long term ambient storage. This was attributed to the difference in the chemical composition of the two polymers, as CYTOP is a fluoropolymer, while PMMA is an ester group containing organic polymer. We show, passivation of the active layer with the proper organic film improves the stability of the high-performance solution-processed IZO TFTs.

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