The present invention provides a method for manufacturing a semiconductor device in which productivity of the semiconductor device is improved. An acrylic resin acting as a photosensitive resin forming a protrusion 5 is applied on a protective film 4 to form a resin layer. A mask having an opening is positioned and arranged at a specified position on the resin layer, and further the mask is irradiated with ultraviolet rays to expose to light the resin layer which is exposed from the opening. By ultraviolet-curing the resin, a cylindrical protrusion 5b having a flat top surface is formed. Then,by irradiating the protrusion 5b with infrared rays 11, the protrusion 5b is heated to melt the acrylic resin forming the protrusion 5b. Since the surface tension is generated in the molten acrylic resin, the top surface of the protrusion 5b which has been the flat surface is deformed into a smooth curved surface. Consequently, the almost semispheric protrusion 5 is formed from the protrusion 5b.