Patent ID: 7196771

Claim:
A photolithography system that includes a reticle stage that supports a reflective recticle, a wafer that is positioned downstream from the reflective reticle, an illumination device comprising a condenser that processes radiation from a source of extreme ultraviolet radiation to produce an illumination field that illuminates the reticle wherein the stage moves in a direction that is transverse to the length of the illumination field and a projection optics device that collects radiation reflected from the reflective reticle and directs the radiation toward the wafer, wherein the system comprises: (a) a detector, that comprises a linear array of discrete photodiodes adjacent the reticle wherein each photodiode generates an electrical signal that is indicative of intensity and wherein the array is scaled to image the entire length of the illumination field, that measures the intensity profile along the entire length of the radiation that is projected on the reflective reticle to generate a measured intensity profile that is compared to a preset intensity profile; and (b) a device that modifies the photolithography system so that the measured intensity profile is restored to a desired level.