Abstract

The advancement of microfluidics in biomedical diagnostics and lab-on-a-chip systems is increasingly dependent on the ability to fabricate complex, three-dimensional architectures with high-resolution negative features. While Digital Light Processing Stereolithography (DLP-SLA) has emerged as a leading fabrication method, it remains constrained by a fundamental trade-off between feature resolution and build volume, as well as challenges regarding fabrication consistency and design accessibility. This dissertation presents an integrated ecosystem of hardware, materials, and software designed to overcome these barriers and enable scalable, high-resolution microfluidic fabrication. We first introduce a novel multi-resolution 3D printing technique utilizing a dual-optical engine architecture, comprising a Very High Resolution Optical Engine (VHROE) with a 750 nm pixel pitch and a Main Optical Engine (MOE, 15 μm pixel pitch), coupled with custom resin formulations featuring wavelength-dependent UV absorbers. This system achieves true 3D multi-resolution control, enabling the fabrication of fully enclosed channels with cross-sections as small as 1.9 µm × 2.0 µm, a significant miniaturization over previous DLP-SLA methods. Next, we developed a vacuum-enhanced printing platform that eliminates defect-causing bubbles by degassing resin in situ, complemented by active irradiance correction to ensure uniform fabrication across the entire build area. This platform is demonstrated through the high-yield production of large-scale arrays containing thousands of functional membrane valves and 7 μm isoporous membranes. Furthermore, we present PyMFCAD, an open-source Python-based design framework that utilizes a modular, component-based architecture to provide voxel-level control and embed validated print parameters directly into design blocks. Finally, we detail the development of the Open Source 1 (OS1) 3D printer, a fully documented, open-source DLP-SLA platform featuring automated calibration and modular software. By providing this comprehensive framework of open-source tools and high-resolution fabrication techniques, this work establishes a robust pathway for the research community to adopt and extend our methods to develop the next generation of high-performance, complex microfluidic devices.

Degree

PhD

College and Department

Ira A. Fulton College of Engineering; Electrical and Computer Engineering

Rights

https://lib.byu.edu/about/copyright/