Comparison of nanosecond and femtosecond laser selective patterning technology applied in organic solar cells interconnection

Laser selective patterning of organic polymer thin-films for electrical serial interconnection of organic photovoltaic cells has been investigated. Organic photovoltaic cells are composed of several layers of organic materials based on bulk heterojunction structure, such as poly(3,4-ethylene-dioxythiophene)-poly(styrene-sulfonate)(PEDOT:PSS) blending and poly(3-hexylthiophene-2,5-diyl)(P3HT) with fullerenes (phenyl-Cn-butyric-acid-methyl-ester)(PCBM) blending. They are spin-coated separately on ITO(Indium tin oxide) coated glass to form multiple thin layers. Pulsed nanosecond and femtosecond lasers are applied to different layers to study the ablation characteristics. The results demonstrate the ability of laser selective patterning of different materials, which can be used to construct the serial interconnection of organic solar cells to increase the voltage output and form large scale modules for practical applications.