Indium Tin Oxide (ITO) is an optically transparent electrical conductor used as an anode in flat panel display applications. Recent studies have shown that laser micromachining is capable of patterning ITO on glass substrates. However, few studies have investigated micromachining of ITO on polymer substrates for flexible display applications. This work reviews the literature on laser micromachining of ITO on glass and polymer substrates and discusses the possible ablation mechanisms in both cases. Potential contributions from thermal phenomena and thermal stress are considered. The results of experimental studies of ITO on PET substrates are presented, including etch rate as a function of fluence and characterization of the ablated region. These experiments are performed using an Nd:YAG laser at the fundamental wavelength.

Topics
Laser micromachining, Transition metal oxides, Glass, Etching, Electrical conductor, Thermal effects
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2003
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