Covering the surface of a substrate such as a silicon wafer with a highly photosensitive photoresist, and then irradiating the substrate surface with specific light (usually ultraviolet light, deep ultraviolet light, extreme ultraviolet light) through a mask containing target pattern information, the photoresist irradiated by the light will react. Therefore, the area irradiated after development will produce different effects from the area not irradiated (depending on the properties of the photoresist).
