“…Epoxy-based SU-8 is a high-contrast, near-UV negative photo-resist applied in the microelectromechanical systems (MEMS) field due to its good mechanical and chemical stability, ease of processing, good optical properties, and ability to form high-aspect-ratio (HAR) structures [1,2]. In earlier work, SU-8 was used as a thick-film photo-resist to realize HAR patterns in the UV LIGA process [3], but several later approaches have used SU-8 as a popular material in other areas of microfabrication, ranging from optics [4,5] to microgrippers [6,7], and microfluidic devices [8,9] due to its diversified functionality as a self-sacrificial layer or sacrificial material for etching [10,11], and as a structural material integral to the fabricated device [6,12].…”