Patent ID: 6958864

Claim:
A photolithography tool comprising: condenser optics positioned to receive light from a light source, said condenser optics positioned to direct an optical beam formed from said light through a reticle; and projection optics configured to form an image of said reticle onto a substrate, said projection optics including: one or more cubic crystalline lens elements receiving said directed optical beam propagated through said reticle, said one or more cubic crystalline lens elements having intrinsic birefringence which introduces retardance aberrations into said optical beam; and at least one uniaxial birefringent optical element positioned along a common optical pathway with said reticle and said one or more cubic crystalline lens elements, said uniaxial birefringent optical element comprising a uniaxial birefringent medium having a single birefringent axis, said uniaxial birefringent optical element having birefringence which introduces retardance aberrations into said optical beam that are substantially conjugate to said retardance aberrations introduced by said one or more cubic crystalline lens elements.