Rapid and High-Fidelity Fabrication of Embedded Elastomeric Photomask for Wafer-Scale Sub-Micrometer Conformal Contact Photolithography.

Photolithography is the mainstream technology used in micro/nanofabrication. While projection photolithography is widely used in production, with a resolution close to the wavelength of the light source, its processes are complicated and expensive. Moreover, in projection photolithography, scanning and splicing are required to achieve large-area exposure at the wafer level, which reduces throughput in production. Contact photolithography offers a cost-effective and parallel exposure solution, but achieving uniform resolution over large areas with micrometer or sub-micrometer resolution remains a challenge. In this study, we propose a conformal contact photolithography strategy based on a wafer-scale embedded elastomeric mask. By optimizing metal patterning and embedding transfer processes, we significantly improve the area (wafer-scale) and efficiency (lift-off and metal transfer process within seconds) of metal-embedded elastomeric mask fabrication. This method enables the rapid and cost-effective fabrication of large-area sub-micrometer-resolution structures, with broad applications in the production of sub-micrometer devices and academic research.