AUXILIARY FILM

The present invention provides an auxiliary film comprising a body and a plurality of microstructures formed on a first surface of the body, the microstructures include a concave-convex appearance on the first surface, and the microstructures have two ends extending to the periphery of the first surface respectively. When the auxiliary film is attached to a pre-protected surface of a substrate, the microstructures and the surface of the substrate form several open-air channels to increase the separation efficiency of the main body from the substrate and reduce the overall process time.