Page 10 - ME News Spring 2022

Next-Gen Manufacturing
NEW METHODS FOR POLLUTION DETECTION
Distinguished McKnight University Professor Tianhong Cui’s laboratory works on microelectromechanical systems (MEMS) and advanced manufacturing in micro- and nano-scale for applications to healthcare and the environment. He is a pioneer in integrating “bottom-up” layer-by-layer nanoscale self-assembly of nanomaterials with “top- down” microfabrication for new sensors, actuators, microfluidics, and photovoltaics.
One novel manufacturing approach he has pioneered is shrink
polymer nanomanufacturing. This
is an entirely new approach to fabricating nanoscale features. In traditional micro electro mechanical devices, microscale structures and electronics are often fabricated on rigid silicon wafers using lithography.
Professor Cui’s group has developed a novel approach that relies on polymer shrinkage to create nanoscale features. Micro-scale features are embossed onto a
polymer film using a unique, one-
of-kind, hot embossing machine in
Cui’s laboratory. The polymer film
with imprinted microstructures is
subsequently “shrunk” to achieve
nanoscale features. Both two- and
three-dimensional embossed
structures can be shrunk into a much
smaller scale. The result is a fully integrated electro-mechanical device with nanoscale features, which can not be realized by lithography.
10 ME News Spring 2022
These devices have an extremely high aspect ratio (sensor feature dimension to surface area) that leads to enhanced sensing capabilities.
This polymer-shrinking is a new manufacturing process that Cui’s group has applied to develop sensors with ultra high sensitivity for cancer diagnostics and detection of water pollutants.