Electrochromism in indium-tin-oxide films for laser-writing application

We report for the first time laser-writing application on an electrochemically NH4+ ion intercalated indium-tin oxide (ITO). NH4+ ion intercalation results into a color change from transparent to brown with a significant enhancement of the surface roughness. Both bare and intercalated ITO's are explored for their structural, surface morphological, and wettability studies. Upon NH4+ intercalation, both an optical absorbance and the surface wettability of ITO changes substantially. A micrometer-scale laser-writing application on intercalated ITO film is achieved after exposing an Ar-ion laser that is non-erasable even after a period of six months. This idea can be used for maintaining long-term safe secrete data.