Improve reproducibility of 3D microfabrication by laser-assisted electrophoretic deposition using feedback stage control

Abstract

Advancements in three-dimensional microdevices have led to the development of intricate microfabrication techniques, aiming to overcome the limitations of conventional methods like photolithography and focused ion beams. While these methods are effective, they entail complexities or demand expensive setups, spurring the quest for simpler, cost-effective alternatives. In the realm of metal additive manufacturing, we have demonstrated a promising technique called laser-assisted electrophoretic deposition (LAEPD), which combines laser trapping and electrophoresis. This innovative method enables precise nanoparticle deposition onto conductive substrates, facilitating the creation of sub-micrometer structures such as pillars. However, its commercial scalability faces a significant hurdle—reproducibility. In this research, to address this challenge, we developed a feedback-controlled approach to LAEPD. Through a programming language (viz. C++ with OpenCV image processing), we regulate deposition velocity during redeposition, crucial for enhancing reproducibility. By utilizing CCD cameras to capture laser spot references, we've successfully refined the process, ensuring consistent and reliable fabrication of microstructures. This breakthrough holds substantial promise, surmounting previous barriers to reproducibility within LAEPD. Our innovative feedback-controlled system not only improves the manufacturing success rate but also sets the stage for practical, commercially viable three-dimensional microfabrication technologies, fostering a pathway toward scaled production of intricate microdevices.