UV Laser Scribing for Perovskite Solar Modules Fabrication, Pros, and Cons

Laser scribing is one of the most challenging steps in fabricating solar modules, which determines their internal resistance, geometrical factor, and efficiency. Pulsed Nd:YVO4 lasers with wavelengths of 355, 532, and 1064 nm are the most common lasers used in the photovoltaic industry. As using one single laser source for all scribing steps is more cost effective, in this article after summarizing recent progress in laser scribing for perovskite modules, a nanosecond UV-laser (355 nm) is used for all scribing steps needed for series interconnections in structures with glass or plastic substrates and studied how different scribing parameters, such as repetition frequency, output average power density, and scan speed, must be selected to adjust the transferred power density to the layer, enabling efficient scribing without overheating and cracking the layers. In addition to producing sharp strips on glass/ transparent conducting layer (TCO) substrates, especially thick fluorine-doped tin oxide, nanosecond UV laser provides a wide window for patterning the perovskite layer without damaging glass/TCO. However, in the case of plastic substrates, melted materials deform the edges of the strips' profiles. These results, along with reviewed results from the literature, provide a good insight into optimized laser scribing for perovskite solar module fabrication.