Evaluation of damaged region at the groove edge of TCO film in pulsed fiber laser processing

Abstract

Nonosecond pulsed fiber laser has been widely used for the removal of TCO film, because of its compact oscillator with the flexible processing head. However, the wide bandwidth of wavelength from the fiber laser would deteriorate the edge quality of groove such as cracks and burrs at the resolidified region due to the chromatic aberration. Therefore, the edge quality of scribed groove was experimentally investigated in the removal process of TCO film by the nanosecond pulsed fiber laser of 1060nm in wavelength. The damaged region such as cracks and burrs at the edge of groove could be improved by using achromatic focusing lenses. The singlet lens for focusing optics led to the large damaged region at the edge of groove, and the cracks and burrs appeared remarkably with increasing the pulse energy. The combination of singlet focusing lens and a circle mask to trim the laser beam made it possible to become the damaged region smaller, since the intensity distribution of laser beam could be sharpen at the edge by using the mask with an appropriate diameter hole.Nonosecond pulsed fiber laser has been widely used for the removal of TCO film, because of its compact oscillator with the flexible processing head. However, the wide bandwidth of wavelength from the fiber laser would deteriorate the edge quality of groove such as cracks and burrs at the resolidified region due to the chromatic aberration. Therefore, the edge quality of scribed groove was experimentally investigated in the removal process of TCO film by the nanosecond pulsed fiber laser of 1060nm in wavelength. The damaged region such as cracks and burrs at the edge of groove could be improved by using achromatic focusing lenses. The singlet lens for focusing optics led to the large damaged region at the edge of groove, and the cracks and burrs appeared remarkably with increasing the pulse energy. The combination of singlet focusing lens and a circle mask to trim the laser beam made it possible to become the damaged region smaller, since the intensity distribution of laser beam could be sharpen at the edg...