12/7/01

ARO Introduces 157 nm Lenses and Windows

Alpine Research Optics (ARO, Boulder, CO) has introduced a new series of CaF2 optics for use in 157 nm laser-based applications, such as microlithography and micromachining. The standard product line includes spherical lenses, cylindrical lenses and flat windows. Both spherical lenses and windows come in diameters of up to 75 mm, and the lenses are offered with radius of curvature between 0.05 and 10 meters. Cylindrical lenses are available with radius of curvature between 0.05 and 10 meters, and can be produced in lengths of up to 75 mm.

All these optics utilize an anti-reflection coating that delivers a reflectivity of less than 0.5% per surface, yielding a total typical transmission of over 98%. In addition to standard products, ARO also offers customer-specified apertures and focal lengths.

These high-performance CaF2 optics are produced at ARO's vertically-integrated UV optics facility, where grinding, polishing, and coating are all carried out under one roof. According to company President, Dave Collier, "At 157 nm, it is now well-documented that the key to longevity and damage resistance is control of contamination during fabrication and use. By polishing our own substrates and coating these optics in a single, controlled environment, we have shown that we can eliminate these contamination effects at the fabrication stage. And by investing in new coating chambers dedicated solely to 157 nm we also eliminate any possibility of cross-contamination during coating."