Selective Patterning of ITO on flexible PET Substrate by 1064 nm picosecond Laser

Pulsed picosecond laser ablation of indium tin oxide (ITO) coated on flexible polyethylene terephthalate (PET) substrate has been investigated. Pulses with 355 nm, 532 nm and 1064 nm wavelengths are performed for comparison. Laser irradiation from the front side and the back side are analyzed. The single pulse ablation threshold is found at 0.56 J/cm2 from the study of the spot sizes varied according to pulse fluence. The overlap rate in multi pulses ablation of ITO layer is discussed during the scribing of lines. Optical microscopy, SEM, surface stylus and EDX analysis reveal that the ITO layer can be completely removed with little damage of the PET substrate using optimized parameters.