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arXiv · 2212.06441

Inverse Design of High-NA Metalens for Maskless Lithography

Haejun Chung·Feng Zhang·Hao Li·Owen D. Miller·Henry I. Smith
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Abstract

We demonstrate an axisymmetric inverse-designed metalens to improve the performance of zone-plate-array lithography (ZPAL), one of the maskless lithography approaches, that offer a new paradigm for nanoscale research and industry. First, we derive a computational upper bound for a unit-cell-based axisymmetric metalens. Then, we demonstrate a fabrication-compatible inverse-designed metalens with 85.50\% transmission normalized focusing efficiency at 0.6 numerical aperture at 405nm wavelength; a higher efficiency than a theoretical gradient index lens design (79.98\%). We also demonstrate experimental validation for our axisymmetric inverse-designed metalens via electron beam lithography. Metalens-based maskless lithography may open a new way of achieving low-cost, large-area nanofabrication.

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Haejun Chung, Feng Zhang, Hao Li, Owen D. Miller, Henry I. Smith. 2022-12-13. Inverse Design of High-NA Metalens for Maskless Lithography. https://arxiv.org/abs/2212.06441

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