Patterning properties of indium-tin oxide layer depending on the irradiation conditions of Nd:YVO4 laser beam

A Q-switched Nd:YVO4 laser (lambda = 1064nm) with a galvanometric scanning system was used for the direct etching of an indium-tin oxide (ITO) film on a glass substrate. The etching properties of the ITO film depending on a pulse repetition rate were investigated. At a low pulse repetition rate of 10kHz, the etching selectivity of ITO to soda-lime glass was poor. so that the glass substrate was also etched. In addition, the lamer spot size formed at a lower repetition rate resulted in more severe ripples along the etched ITO line. In this experiment. it was shown that a pulse repetition rate higher than 40 kHz was adequate for the etching of an ITO film with a thickness of 1,200 angstrom on soda-lime glass. In particular, the larger spot size formed at the lower repetition rate resulted in more severe ripples along the etched ITO line. In our experiment. a 40 kHz repetition rate tit a scanning speed of 500 mm/s was suitable for the formation of plasma display panel (PDP) bus electrodes.