Fresnel Zone Plate Manufacturability Analysis for Direct-Write Lithography by Simulating Focusing and Patterning Performance versus Fabrication Errors

Zone plate array lithography (ZPAL) in the X-ray or EUV regimes is one possible next-generation lithography solution because of its potential for high-resolution and maskless operation. To achieve a high throughput, Fresnel zone plates (FZPs) are integrated to form arrays of massively parallel exposure beams. FZP fabrication errors and uniformity can be serious issues in ZPAL systems, which are usually assembled and tested directly after zone plate arrays (ZPAs) are fabricated. The yield of this approach can decrease significantly with increasing beam number. A new ZPA design-to-manufacture flow that takes fabrication errors into account before the assembly process is proposed. The errors can be clearly screened by rigorous optical and lithography simulations. The effectiveness of the proposed approach is demonstrated by analyzing preliminary FZP designs of different zone numbers subject to imperfect zone width control. Simulation results indicate that FZPs with smaller zone numbers can tolerate larger radius deviations.