SU8 Photolithography of 45x45x80μm pillars on a silicon wafer

Since IBM’s development in 1989 of SU-8 photoresist for use as a key component for high-resolution microelectronics manufacturing, other industries have adopted the photosensitive polymer for a wide range of applications.  Whether fabricating microfluidics, micro pillars and cylinders, tiny gears and cantilevers, or optical waveguides, SU-8’s unique material properties expand the capabilities of miniature products.  SU-8 is now a standard material used for manufacturing microfluidic devices, microelectromechanical systems [MEMS] and micro-reactors.

SU-8 is a negative photoresist, meaning that after it is imaged with UV light and cured the design is almost permanently adhered to the substrate.  It is mechanically, thermally and chemically stable, and can be coated onto substrates yielding high aspect ratio features.

The use of SU-8 with photolithography also provides Potomac with yet another tool for the fabrication of microfluidic features on silicon, a material with high thermal organic and chemical resistance used in microreactors for pharmaceutical, chemical and biochemical applications. Potomac’s R&D team is actively collaborating with industrial and academic partners to commercialize this technology for pharmaceutical, chemical and biochemical applications.  Recently, this technology has also found its way into the field of single-cell sequencing. Features seen in the images here are 45x45x80mm pillars that provide the means to cast silicone (Poly-dimethyl siloxane, PDMS) molds that produce micro-wells for trapping single cells.  

SU-8 photolithography as well as standard photolithographic techniques are just a few of the growing number of tools Potomac utilizes to provide rapid, cost-effective and innovative fabrication solutions for advanced manufacturing applications.  From laser machining, etching or welding, micro-CNC machining, 3D Printing, hot embossing or SU-8 photolithograph, Potomac can select the right tool for the specific job.

We would like to give a special mention to Tim Buckheit, University of Maryland Baltimore County (UMBC), Microfabrication, Machining, and Electronics (MME), for providing services as well as lending his expertise to our SU-8 photolithography development project.


Caption: A) SU8 mold 45x45x80um and B) PDMS molds 45x45x80 um