FAIRPORT, NY – Corning Tropel Corp., a wholly owned subsidiary of Corning Inc., has released its new line of long-working-distance deep-UV micro-objectives, the μCAT(tm) (microCAT) family. Micro-objectives are used by the semiconductor and related industries to inspect images printed on wafers and photomasks.
Typically, end users of micro-objectives order custom lens designs to fit into their ultraviolet (UV) systems. With the microCAT family as an OEM solution, customers are now able to purchase off-the-shelf standardized micro-objectives for their UV systems. Also, because the microCAT family has standard specifications, most customers receive the micro-objective in a matter of weeks, as compared to longer lead times for custom lenses.
The product family consists of three micro-objectives: the microCAT Tiger and Panther, which are currently available, and the microCAT Cheetah, which will be available in the fourth quarter 2001. Each micro-objective is catadioptric, incorporating both refractive and reflective elements. This allows lens designers the flexibility to manipulate surface curves, element thickness, and glass type in order to optimize lens performance. The result is a micro-objective with long working distance, allowing the distance between the micro-objective and the wafer or photomask to be up to 9mm, which reduces the risk of damage during inspection. In addition, it has very high Numerical Aperture (0.52 to 0.90), and very low central obscuration for improved image contrast.
The product also is a sealed system. The internal atmosphere of each objective is controlled to prevent harmful environmental contaminants, such as hydrocarbons, from depositing or photopolymerizing on the internal components. These deposits greatly reduce UV transmission and can shorten the micro-objective's life.
While each of the microCAT products has a specified Numerical Aperture, they are available in a variety of UV wavelengths extending from 256nm to 157nm. In addition, each micro-objective is certified at those UV wavelengths to verify that performance exceeds published specifications.
Product specifications for the Corning Tropel microCAT family of micro-objectives are available at For more information, visit Corning Tropel Corp.