Abstract: The invention discloses a method for preparing an anticorrosive surface layer of a metal material in a marine environment by laser, which belongs to the technical field of laser processing. First, the laser cladding method is used to prepare a cladding surface layer on the surface of the metal material that is not easy to undergo chemical substitution reaction with the chlorides (NaCl, MgCl2 , CaCl2 etc.) in the seawater. Then, on the surface of the cladding surface layer, ultrafast laser processing is used to form a surface layer with a wetting angle (and water) greater than 90 degrees and with hydrophobic characteristics.

Abstract: A mask manufacturing method and a semiconductor device manufacturing method are provided. The methods form a plurality of dummy patterns without any change in hierarchical structure to reduce a turn-around time (TAT) and a performance of a system. The mask manufacturing method includes designing a layout of a main pattern, performing integrated optical proximity correction (OPC) on the layout, delivering design data, obtained through the integrated OPC, as mask tape-out (MTO) design data, preparing mask data based on the MTO design data, and exposing a substrate for a mask, based on the mask data, wherein the performing of the integrated OPC includes generating a dummy pattern in a state of maintaining hierarchical structure.