Patent ID: 8305560
Filing Date: 2012-11-06
Classification: G03F

Abstract:
1. An exposure apparatus comprising: an illumination optical system configured to illuminate a mask; a projection optical system configured to project an image of a pattern of the mask onto a substrate; a wavefront splitting device configured to form a secondary light source at a position conjugate with a pupil plane in the projection optical system; and an aperture stop arranged at a position that is shifted from a focal plane on an exit side of the wavefront splitting device, wherein the aperture stop includes a light shielding part, an opening part, and a light attenuation part that is located between the light shielding part and the opening part, and has a transmittance larger than that of the light shielding part and smaller than that of the opening part, and wherein a width of the light attenuation part is set within a range from a wavefront splitting period of the wavefront splitting device or a value of Z×tan(arcsin(α))/2 to a length that is five times as long as the wavefront splitting period of the wavefront splitting device, where α is a numerical aperture on an exit side of the wavefront splitting device, and Z is a distance between the focal plane of the wavefront splitting device on the exit side and the aperture stop.