Parallel maskless optical lithography for prototyping, low-volume production, and research

Abstract

Earlier we reported on a proof-of-concept maskless-lithography system that used an array of Fresnel zone plates to focus multiple beams of 442 nm light onto a substrate, and micromechanics for multiplexing light to the several zone plates, enabling patterns of arbitrary geometry, at 350 nm linewidth, to be written. We referred to the technique as zone-plate-array lithography (ZPAL). We also demonstrated zone-plate-array microscopy. Here, we report on a “preprototype” ZPAL system operating at an exposure wavelength of 400 nm, capable of quick-turn-around, maskless lithography. We describe the lithography results with this system as well the development of high-speed data delivery systems, high-numerical-aperture zone plates (up to 0.95), and a multiplexing scheme that will enable us to move to a “full-prototype” system capable of 210 nm feature sizes at a moderate but useful throughput of ∼0.25 cm2 in 20 min.