USPTO Awards Patent to Luminescent for Inverse Lithography Technology

Luminescent Technologies, Inc., a provider of revolutionary lithography-enhancement products to the semiconductor industry, has bolstered its intellectual property portfolio with a second patent granted for the company’s Inverse Lithography Technology (ILT), a ground-breaking resolution enhancement technology (RET) solution. The new patent (No. 7,178,127 B2) was issued by the U.S. Patent and Trademark Office on Feb. 13, 2007. It covers the use of level-set methods when applied to advanced lithography applications.

Level-set methods represent one of the key innovations behind Luminescent’s ILT. It is the core cylinder of the engine that generated the 45- and 32-nm patterning results revealed by the company at the recent SPIE Advanced Lithography Conference. First invented by Dr. Stanley Osher in 1988, level-set methods have been successfully used in multiple engineering disciplines for diverse applications. Now, Luminescent is optimizing the technique to build and commercialize a robust mask-synthesis solution that is vastly superior to conventional optical proximity correction (OPC) methodologies.

“With two patents granted and another 19 pending, our breakthrough technology enjoys a strong IP position,” said Luminescent CEO, David Fried. “Our ILT products continue to out-perform the capabilities of state-of-the-art OPC, consistently producing better pattern fidelity and the broadest possible lithography process windows on printed silicon. Customer interest is high and our installed base of ILT products continues to expand.”

Patent Abstract:
“Photomask patterns are represented using contours that are defined by level-set functions. Given a target pattern, contours are optimized such that a defined photomask — when used in a photolithographic process — prints a wafer pattern that is faithful to the target pattern. Optimization utilizes “merit function” for encoding aspects of photolithographic processes, preferences relating to resulting pattern (e.g. restriction to rectilinear patterns) and robustness against process variations, as well as restrictions imposed on the practical and economic manufacturability of photomasks.”

About Inverse Lithography Technology
Inverse Lithography Technology (ILT), developed by Luminescent, is the semiconductor industry’s first mask synthesis solution to transition beyond the limitations of optical proximity correction (OPC) software. It is the only automated resolution enhancement technology (RET) that starts directly with the desired IC pattern on the wafer, explores the entire available optical lithography space by mathematical inversion, and ultimately delivers a manufacturable mask pattern that generates the maximum design fidelity with the broadest possible process window. A new-generation RET solution, ILT fits seamlessly into existing tape-out flows and leverages current-generation 193- nm lithography equipment to pattern 45- and 32-nm IC designs.

About Luminescent’s ILT Products
ILT is the engine that drives the company’s Luminizer product family — a configurable and highly scalable integrated hardware and software platform with multiple cutting-edge applications. The Luminizer family includes the Luminizer FX for full-chip correction at nodes of 90 nm down to 32 nm, and the Luminizer LE for small-area cell optimization.

About Luminescent Technologies, Inc.
Luminescent provides lithography technology to the semiconductor industry. The company’s Inverse Lithography Technology (ILT) products turn design intent into production reality by improving on-wafer pattern fidelity, expanding process windows, and accelerating time-to-silicon. Luminescent is a privately held, venture-backed company based in Palo Alto, California.