Development of 3D Simulator for Single-Step Negative Tone Thick Film Projection Photolithography

Three-dimensional (3D) photoresist structures fabricated by an optical lithography have been widely used in application fields such as microfluidics, micro total analysis systems (μ-TAS), or biosensors. To date, various 3D lithography methods have been proposed. Here we study 3D thick film photolithography technique using projection lithography system for fabricating complex microstructures used in microfluidics or bio-engineering tools. In this lithography method, prediction of 3D structure profile to be fabricated which depends on the mask pattern, exposure dose and the focus depth is difficult by the existing simulation models. So, this paper reports on the simulation method for single-step negative tone thick film projection lithography. Validity of the proposed simulation approach were confirmed quantitatively by comparing with experimental results and simulated results.