Imec advances single-patterning capabilities of high-NA litho

Imec again reports progress in high-NA EUV lithography, showing single-patterned damascene structures at 20nm pitch and 13nm tip-to-tip (T2T) dimensions. Presented at the SPIE Photomask Technology + EUV Lithography Conference, the results mark a step forward in enabling single-exposure patterning for advanced logic nodes.

In addition to the damascene work, Imec also demonstrated direct metal etch (DME) of ruthenium lines at both 20nm and 18nm pitch. The 20nm structures achieved 100 percent electrical yield, with CD uniformity reportedly around 3nm. The experiments used metal oxide resists and were optimized in collaboration with partners on masks, underlayers and optics.

The work supports Imec’s – and the industry’s – goal of reducing reliance on complex multi-patterning as logic scaling progresses below the 2nm node. “Achieving these logic designs with single-print high-NA EUV lithography reduces processing steps compared to multi-patterning, lowering fabrication costs and environmental impact and improving yield,” comments Steven Scheer, senior vice president Compute System Scaling at Imec.