A research team from the Chinese Academy of Sciences, Jilin University, and the State Key Laboratory of Advanced Optical System Manufacturing published a technical paper in the journal iScience in August 2026, reviewing the potential of a platinum-tungsten (Pt-W) alloy as an innovative material for mask absorbers in extreme ultraviolet (EUV) lithography technology.
What does this research offer?
The study focuses on addressing challenges associated with the next generation of High-Numerical Aperture (High-NA) EUV lithography. As manufacturing precision increases, the thickness of traditional mask absorbers becomes an obstacle to image quality due to 3D shadowing effects. The study proposes using a Pt-W alloy as an alternative characterized by improved physical and optical properties, allowing for a reduction in absorber thickness without compromising light-blocking efficiency.
Why does this development matter?
Mask absorbers are a critical component in lithography precision. In High-NA EUV technologies, reducing the thickness of the absorber minimizes optical aberrations caused by oblique light incidence angles, which is essential for producing semiconductors at smaller nanometer sizes. Using a Pt-W alloy may provide a better balance between the refractive index (low-n) and imaging performance, opening the door to improving the precision of patterns printed on silicon wafers.
Practical implications
The study relies on physical vapor deposition (PVD) techniques to create these thin films, with a precise evaluation of their properties under EUV exposure conditions. This research represents a step in the search for new materials capable of withstanding advanced manufacturing requirements, as traditional materials continue to face performance limitations as technical nodes are further scaled down.
These results underscore the importance of developing mask materials compatible with High-NA requirements, where the challenge is not limited to laser precision but extends to the physical materials that form the infrastructure of the photolithography process.