▎ 摘　　要

NOVELTY - The assembly has an outer surface and an inner surface connected with each other. A conformal coating is formed on an outer surface of a protective film. The protective film comprises a nano-tube thin film layer. The nano-tube thin film layer has a thickness of 10 nm to 100 nm. The nano-tube film layer comprises a randomly oriented nano-tube or a directionally oriented nano-tube. The protective film comprises a graphene thin film layer. A mounting frame is attached to a frame, where the frame contacts the inner surface of the protective film. USE - Protection assembly for use during an optical lithography patterning process. ADVANTAGE - The assembly has high transmittance, low deflection and small micropore size. The assembly uses the conformal coating to protect the protective film against damage of heat and hydrogen plasma generated during extreme ultraviolet (EUV) exposure. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: a method for forming a doubling light cover assembly; and a method for increasing service life of a protective film. DESCRIPTION OF DRAWING(S) - The drawing shows a flowchart illustrating a method for preparing a multilayer structure of a protective film. (Drawing includes non-English language text). 500Step for placing frame adjacent to surface of first film layer 510Step for applying pressure to fix first film layer to frame 520Step for paving frame and any attached film layer on surface of additional film layer 530Step for applying pressure to fix additional film layer to attached film layer 535Step for coating conformal coating to protective film