SU-8 5S is a negative photoresist used in microfabrication for creating high-resolution patterns on substrates. It is commonly used in MEMS, microfluidics, and other microelectronics applications., SU-8 5S is a viscous liquid that is spin-coated onto a substrate and then exposed to UV light through a photomask. The exposed areas become cross-linked and insoluble, while the unexposed areas are removed with a developer. This is supplied by Microchem.