Scribing of Thin-film Solar Cells with Picosecond Laser Pulses

The thin-film CIGS technologies for photovoltaics are attractive due to their potential low cost and optimal performance. Efficiency of cells with a large area might be maintained if small segments are interconnected in series in order to reduce photocurrent in thin films and resistance losses, and laser scribing process is crucial for performance of the device. We present our results on scribing of CIGS thin-film solar cells with single and multiple parallel laser beams with the picosecond pulse duration. Solar-cell performance tests were performed before and after laser scribing together with Raman spectroscopy analysis. The quality of processing was evaluated with optical and scanning electron microscopes.