In this study, we report a simple route to the low-temperature crystallization of solution-processed indium oxide thin films by introducing ammonium nitrate in the sol–gel metal oxide precursor solution as photoactivable additive and applying deep ultraviolet (DUV) irradiation onto the as-spun oxide films in an inert atmosphere. Thermal and structural analyses revealed that the initial temperatures for condensation and crystallization were reduced down to 130 and 200 °C, respectively, by the in situ generation of reactive chemical species enabled by DUV-assisted nitrate photolysis. Furthermore, transmission electron microscopy confirmed that the degree of indium oxide film crystallinity was gradually enhanced as the amount of nitrate in the precursor solution was increased. Finally, electrical characterizations showed that carrier mobility, threshold voltage, subthreshold swing, and threshold voltage shift under the positive bias stress of sol–gel indium oxide thin-film transistors were improved from 0.21 to 5.03 cm2/V s, from 4.18 to 1.64 V, from 1.33 to 0.72 V/dec, and from 6.44 to 4.04 V, respectively, by combining ammonium nitrate and DUV photoactivation.
Low-temperature crystallization of indium oxide thin films with a photoactivable additive
Note: This paper is part of the APL Special Collection on Metal Oxide Thin-Film Electronics.
Jun-Gyu Choi, Won-June Lee, Yong-Ryun Jo, Hyeonjun Na, Sangwoo Lee, Bong-Joong Kim, Myung-Han Yoon; Low-temperature crystallization of indium oxide thin films with a photoactivable additive. Appl. Phys. Lett. 12 December 2022; 121 (24): 243301. https://doi.org/10.1063/5.0127480
Download citation file: