Atomic-layer Additive Manufacturing of Indium(III) Sulfide

Lines of indium(III) sulfides are deposited by atomic-layer additive manufacturing (ALAM) based on the reaction of indium tris(acetylacetonate) with hydrogen sulfide established in atomic layer deposition (ALD). At 160 °C, solid accretion occurs at a rate of 0.04 Å per pass. The layers are continuous, free of observable pinholes, dense, and very smooth, with a root-mean-squares roughness on the order of 0.5 nm found for deposits up to 25 nm thick. The material is nearly stoichiometric, with a S/. In ratio of 1.6 found experimentally by energy-dispersive X-ray microanalysis in cross-section examination by transmission electron microscopy, and it is polycrystalline. This work delivers In2S3 as a dopant or interfacial layer in opto-electronic devices to be prototyped and optimized by ALAM.