A method is proposed for patterning crystalline indium tin oxide (c-ITO) patterns on amorphous ITO thin films by femtosecond laser irradiation at 80 MHz repetition rate followed by chemical etching. proposed approach, the a-ITO film is transformed into a c-ITO film over a predetermined area via the accumulation energy supplied by the high repetition rate laser beam, and the unirradiated a-ITO film is removed using an acidic etchant solution. The fabricated c-ITO patterns are observed using scanning microscopy and cross-sectional transmission electron microscopy. The crystalline, optical, properties were measured by X-ray diffraction, spectrophotometer, and four point probe respectively. The experimental results show that a high repetition rate reduces thermal shock and corresponding improvement in the surface properties of the c-ITO patterns. (C) 2010 Elsevier B.V. All rights reserved.