Disclosed herein is a semiconductor manufacturing apparatus. The semiconductor manufacturing apparatus precisely adjusts the position and size of a light spot formed on a substrate, enabling formation of a target pattern or elimination of an unnecessary pattern in an accurate and rapid manner. The semiconductor manufacturing apparatus includes a light source, a light modulator to modulate light irradiated from the light source into a plurality of beams to correspond to a target pattern, a diffraction element to adjust a direction of each of the plurality of beams, and an optics system to allow the plurality of beams, the direction of which has been controlled by the diffraction element, to form a light spot having a target size.