PORTLAND, Ore.—Chip equipment vendor KLA-Tencor Corp. rolled out new tools for overlay control and photomask inspection Wednesday (Sept. 5) at the Semicon Taiwan tradeshow in Taipei.
Multi-patterning is growing in use and prominence as semiconductor manufacturing moves below the 28-nm node. But multi-patterning—a lithography technique that enhances feature density on the wafer—also introduces new sources of overlay errors and mask defects.
KLA-Tencor's new Archer 500 Overlay Metrology System is designed for high-volume manufacturing using multi-patterning at sub-28 nanometer nodes. By measuring and characterizing overlay errors, the Archer 500 improves accuracy and measurement speed as well as enabling the use of thin resist stacks and new materials such as opaque hard masks, according to the company.
"The demands of double-, triple-, quadruple- and other multi-layer patterning techniques have created very strict overlay specifications," said Becky Howland, senior director of marketing at KLA-Tencor (Milpitas, Calif.). "The Archer 500 measures on-layer, to-layer and within-layer errors, enabling accurate lithography overlay control for advanced nodes."
KLA-Tencor's Archer 500 has new illumination options that expand overlay measurement capability to new lithography layers and materials.
KLA-Tencor also announced new tools for advanced photomask inspection at 28-nanometer and below. Its X5.2 detects defects and pattern degradation on critical masks down to 28-nm (and non-critical masks down to 20-nm) and the Teron 611 extends inspection of critical masks down to the 20-nanometer and below.
"These smaller pattern features, and their new cleaning processes at 28-nanometer and below, require new tools for reticle monitoring in the fab," said Wilbert Odisho, also a senior director of marketing at KLA-Tencor.
Tiny defects that develop after repeated use of photomasks in a production environment could be ignored at previous nodes, but at 28-nanometer and beyond the introduction of almost any nanoscale defect on masks could affect yields. The X5.2 and Teron 611 tools—called the Total ReQual Solution when used together—are designed to monitor defects and pattern degradation at these advanced nodes. Using KLA-Tencor's fifth-generation STARlight inspection system for both multi- and single-die reticles, the new tools can detect defects on edges, sidewalls and open areas of patterns.