Compact line focus system for laser-based debonding of flexible electronic components

The surface treatment of micro- and nanolayers by means of linear scanning with a line-shaped laser beam gains more and more importance for advanced products. Laser annealing of functional layers to enhance material properties is already an established process, e.g. for coatings on architectural glass or in advanced electronic components, such as flat panel displays. Due to their flexibility, anamorphic beam shaping and homogenization of high-power laser beams constantly find further applications in the selective heating of thin layers. One of these applications is debonding of flexible OLED displays, so called laser lift-off, which was introduced just in recent years. The performance of a laser lift-off system highly depends on the optical properties of the line beam. Good homogeneity in long axis direction, high energy density and sufficient depth of focus are crucial for reliable processing results. However, future system concepts will have to consider additional requirements of an industrial manufacturing environment as the application is maturing. We present a system for laser lift-off of flexible OLED displays, which focuses on a compact and rugged design. Starting from an existing system concept of a line focus system in the infra-red regime we define the requirements for a transition to the ultra-violet spectral range and discuss both, optical and mechanical layout. The optical key parameters are presented and validated by simulation and experiment. We demonstrate the implementation of a functional model.