Photolithographic Feature Fabrication on Acrylic Substrates with Tight Tolerance Height Requirement

该项目旨在生产一种与Alentic MicroScience Inc.商业化的新型无透镜显微镜系统兼容的光学间隔物系统。该间隔物需要非常薄且具有高公差(2.5微米，在整个成像区域内与标称偏差小于1%)，并且最初在丙烯酸基板上生产，但理想地与其他透明聚合物基板兼容。这种格外严密的公差必须在不造成底层丙烯酸基板任何实质性损坏或粗糙度增加的情况下实现，才能用于无透镜微缩影的目标应用。将应用两种主要的制造技术-通过传统的旋涂将薄膜环氧层直接光刻在丙烯酸基板上，以及艾伯塔大学最近获得的双光子直写光刻系统。传统的光刻方法在理论上更具可伸缩性，但并没有表现出成像应用所要求的特殊的一致性。双光子光刻方法可能能够产生所需的均匀性，但只能在非常小的区域(~1 cm^2)上形成图案。因此，在这些情况下，将尝试使用软光刻成型技术进行原理验证测试和复制，以确定为该生产目的放大高质量母版模板的可行性。该项目的结果将是Alentic MicroScience Inc.可以采用的一系列工艺步骤，以最好地满足他们对无透镜成像的生产要求。

This project aims to produce an optical spacer system compatible with a novel lensless microscope system commercialized by Alentic Microscience Inc. The spacers need to be both exceptionally thin and high tolerance (2.5 micrometers with less than 1% deviation from nominal across the imaging area) and produced on an acrylic substrate initially, but ideally compatible with other transparent polymer substrates. This exceptionally tight tolerance must be achieved without any substantial damage or roughness increase of the underlying acrylic substrate to be functional for the target application of lensless microscropy. Two main manufacturing techniques will be applied - direct photolithography of a thin-film epoxy layer onto acrylic substrates via traditional spin-coating, and a two-photon direct write lithography system recently acquired by the University of Alberta. The traditional lithography approach is in theory more scalable, but has not been characterized for the exceptional uniformity required by the imaging application. The two photon lithography approach may be able to produce the uniformity required, but can only pattern over very small areas (~1 cm^2). As such, proof-of-principle tests and replication using soft lithography molding techniques would be attempted in these cases to determine feasibility to up-scale high quality master templates for this production purpose. The result of the project would be a series of process steps that can be adapted by Alentic Microscience Inc. to best approach their production requirements for lensless imaging.