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Micro-Character Printing on a Diamond Plate by Femtosecond Infrared Optical Pulses

Processing of less than 400 nm has been performed on the surface of a diamond plate by means of a femtosecond infrared pulse laser. Various characters with a size of about 1 µm were drawn by the femtosecond pulse laser system in conjunction with a microscope equipped with a precisely controlled piezo-stage. The tightly focused laser light on the flat surface of the diamond made it possible to minimize the light-induced graphitization. The surface of the diamond plate after laser machining was analyzed by micro-Raman measurements to estimate the graphitization effect induced by laser irradiation. The obtained results indicate that graphitization increased with the number of irradiated laser pulses.