This study combines laser flattening, laser imprinting, and laser welding technologies, which have the potential to reduce the impact of the skin effect. Firstly, the surface of copper foil is flattened, the effect of flattening parameters on the flattening effect is investigated, and the flattening mechanism is revealed. Then, the nanostructure is then created using the nanomold on the surface of the flattened annealed copper foil. Finally, laser welding is used to connect the flattened and annealed imprinted copper foil and LCP. Microtension experiments are used to test the bonding strength of the copper foil and LCP treated under various conditions. The sample’s surface morphologies are examined using an atomic force microscope, optical microscope, and a scanning electron microscope, and the mechanisms of flattening, imprinting, and welding are discovered.