In situ Laser-assisted Micrnmachining of Environmentally-responsive Hydrogel Films

Traditional micromachining techniques, such as lithography, etching, and micro-molding, to pattern hydrogel thin films, are time consuming, expensive, and do not scale well to large production. In this paper, we demonstrate a direct laser patterning of environmental responsive hydrogel films, allowing low cost, fast, and scalable fabrication for in situ mass production. We characterized and analyzed a series of transient features of the laser-engineered hydrogel, including the ablated width, sidewall quality, and resolution as a function of laser beam parameters and hydrogel thermal properties at different hydration states (from wet to fully dried). The optimal feature quality is achieved in hydrogels dried for 1–2 hours (40-60% weight loss), thus identifying a temporal window for a rapid end-to-end fabrication.