Patent ID: 6835511
Filing Date: 2004-12-28
Classification: G03F,Y10S

Abstract:
In a microlithography method, performed using a microlithography apparatus, in which a device pattern to be transferred onto a sensitive substrate is defined on a reticle divided into multiple subfields each defining a respective portion of the pattern, the reticle is illuminated subfield-by-subfield with an illumination beam to produce a corresponding patterned beam carrying an aerial image of the illuminated region of the reticle, the aerial image carried by the patterned beam is projected and focused as a subfield image at a respective location on the sensitive substrate, and the subfield images on the substrate are stitched together to form the device pattern on the substrate, a method for correcting deformation of the reticle, comprising:defining multiple position-measurement marks on the reticle; using a reticle-inspection device separate from the microlithography apparatus, detecting respective positional coordinates of at least some of the position-measurement marks on the reticle so as to produce a first set of reticle-deformation data; mounting the reticle in the microlithography apparatus and detecting respective positional coordinates of at least some of the position-measurement marks on the reticle so as to produce a second set of reticle-deformation data; and while performing exposure of the pattern from the reticle to the substrate, correcting one or more of the position and distortion of each subfield according to both the first and second sets of reticle-deformation data.