Laser Patterning of Thin Films

Abstract Laser‐based patterning of thin films has rapidly revolutionized materials processing over the last years and is increasingly replacing conventional patterning techniques such as photolithography or mechanical patterning. Currently, it is widely used for both fundamental research and practical applications. According to the desired requirements, laser and processing parameters can be specifically selected for selective, precise, reproducible, and nearly damage‐free patterning of single layers and layer stacks of a wide variety of materials. This article summarizes the fundamentals and basic processes of laser ablation and discusses the influence of the essential laser parameters on laser–matter interaction. Moreover, an overview on practical aspects such as different optical setups, process control and approaches for selective layer ablation are given. A variety of current examples for the application of lasers for patterning thin films is introduced with a clear focus on photovoltaic applications. These examples highlight that laser patterning is a versatile, flexible, and reliable technique for processing a wide range of thin‐film materials, which will be increasingly implemented in the future.