Accelerated temperature and humidity testing of 2D SnS₂ thin films made via four-inch-wafer-scale atomic layer...

Tin disulfide (SnS₂) has emerged as a promising two-dimensional (2D) material due to its excellent electrical and optical properties. However, research into 2D SnS₂ has mainly focused on its synthesis procedures and applications; its stability to humidity and temperature has yet to be studied. In this work, 2D SnS₂ thin films were grown by atomic layer deposition (ALD) and characterized by various tools, such as x-ray diffraction, Raman analysis, and transmission electron spectroscopy. Characterization reveals that ALD-grown SnS₂ thin films are a high-quality 2D material. After characterization, a four-inch-wafer-scale uniformity test was performed by Raman analysis. Owing to the quality, large-area growth enabled by the ALD process, 98.72% uniformity was obtained. Finally, we calculated the thermodynamic equations for possible reactions between SnS₂ and H₂O to theoretically presurmise the oxidation of SnS₂ during accelerated humidity and temperature testing. After the accelerated humidity and temperature test, x-ray diffraction, Raman analysis, and Auger electron spectroscopy were performed to check whether SnS₂ was oxidized or not. Our data revealed that 2D SnS₂ thin films were stable at humid conditions.