JUNE 19--Corning Tropel Corp. (Fairport, NY; www.corning.com), a manufacturer of ultraviolet (UV) optical systems, claims to have manufactured a lithographic objective lens with the highest resolution in the world. This 15X reduction stepper objective lens projects images onto a specially treated wafer that becomes the circuitry on a semiconductor.
With a numerical aperture (NA) of 0.85, the lens is able to resolve features smaller than 70 nm-the highest resolution ever achieved in a lithographic objective. To achieve such resolution, the lens is able to sustain extremely short wavelengths of ultraviolet light. The lens is currently used by Semiconductor Leading Edge Technologies Ltd. (SELETE), a research consortium of Japanese semiconductor manufacturers, in a 157-nm lithography system.
"The line widths on the circuitry of today's most advanced microchips in production are 130 nm. This lens is capable of resolving features nearly one-half that size, meeting the requirements for next-generation chips," says John Bruning, president and chief executive officer of Corning Tropel. "This lens will be instrumental in helping photoresist manufacturers develop 157-nm resists that are sensitive enough to produce such small features, and also durable enough to meet the performance demands of faster speeds and greater storage capacity."
The 0.85NA objective lens was designed and built for Exitech Ltd., a UK-based manufacturer of laser microprocessing systems. The lens was integrated into Exitech's MS-157 microstepper tool and delivered to SELETE.
"Because this lens has the highest NA and shortest wavelength of operation of any objective used for high-resolution lithographic imaging, it will enable researchers to develop the technologies required for manufacturing the circuits on future generations of silicon chips," says Malcolm Gower, chairman and technical director, Exitech Ltd. "In fact, SELETE researchers are already using the MS-157 tool to image features as small as 50 nm on silicon wafers."
"The delivery of this lens was made possible through advanced research and development and superior manufacturing processes. It demonstrates our commitment to optical lithography at 157 nm for next-generation chip manufacturing," adds Bruning. "This global effort ties together a U.S. manufacturer, a British systems integrator, and a Japanese research organization."