Flexible Fabrication of Flexible Electronics: A General Laser Ablation Strategy for Robust Large-Area Copper-Based Electronics

Attributed to high power density and controllable digital program operation, lasers are a powerful tool in the preparation, prototype fabrication, and post-processing of materials. In this paper, a general laser ablation strategy that can be conducted under ambient, room-temperature, and mask-free conditions is employed for the rapid fabrication of robust large-area copper-based flexible electronics. Micrometer-scale thick copper layer cladded on flexible polymer substrate can be removed efficiently in one laser scanning pass based on laser-induced heat evaporation effect. Metal grids with a width less than 10 microns and a thickness close to 2 microns can be produced in a reliable manner. As proof-of-concept demonstrations, flexible transparent conducting electrodes and a variety of flexible circuit boards (FCBs) with different precisions and dimensions are fabricated by this approach in a digitally controlled mode and their photoelectric properties under normal and deformation states are investigated. The results indicate that the method is robust and as-prepared flexible electrodes and circuits are reliable and endurable, indicative of the potential of this method in scalable fabrication of sub-millimeter flexible electronics through a straightforward and flexible fashion.