A comparative study of via drilling and scribing on PEN and PET substrates for flexible electronic applications using excimer and Nd:YAG laser sources

A study on via drilling and channel scribing on PEN and PET substrates for flexible electronic application is discussed in this paper. For the experiments, both KrF excimer laser (248 nm) and frequency tripled Nd:YAG (355 nm) laser are used. Different measurement techniques like optical microscopy, Dektak profilometer, Confocal microscopy and scanning electron microscopy (SEM) were employed to characterize the quality of the channels and vias. The patterned structures were filled by three different methods using a conductive paste or ink that is cured in an oven at an elevated temperature. The cross-sectional measurements of channels and vias were carried out using SEM to study the uniformity of filling.