By Pola Goldberg Oppenheimer
Birmingham Fellow and Lead for Advanced Nano Materials, Structures and Applications (ANMSA)
We understand the world intuitively over only a tiny range of sizes: sizes in the middle, between ‘’very large’’ and ‘’very small’’ we can comprehend. We know how a splinter stings when it slips under our thumbnail, how much a sack of potatoes weighs, how it feels to kick a football…but, we have never dropped a planet or knowingly sat on an individual atom. When things are approximately our size, we understand them through repeated experience. Over time, our accumulated experience settles into intuition. When things are much bigger than we are, or much smaller, we don’t understand them in the same sense.
My research is about nanotechnology and nanostructures. Its exploits technologies that make the smallest things for various ends: to fabricate the components of computer chips, to control and detect the behaviour of molecules, to manipulate cells. Since each of us is a nation of cells, and our cells are cities of nanostructures, nanoscience and nanostructures could be very useful in medicine.
The ability to build very small things while venturing from macro to micro, to the nano-world offers opportunities for new technologies – technologies so radically outside our experience that we may not even recognise them when they first appear.
My research interests lie in nano and submicron structure formation at surfaces and in thin films, including pioneering the potential use of hierarchical electrohydrodynamically generated functional structures to develop novel polymer-based nano-detection devices.
High resolution lithography is one of the cornerstones of electronic technologies. While these are based on conventional optical projection methods, a range of alternative techniques have emerged over the past 10 years for the control of pattern replication on the 10 nanometre to 1 micrometre length scale. My research takes lithography to a new level by the development of techniques that control structure formation within the replicated material down to the atomic level. This results in the controlled manufacture of design patterns with hierarchical feature sizes. Using the the electro-hydrodynamic lithography (EHL) technique, a design electrode pattern is replicated into a polymeric resist by electric field-gradient forces. This method reliably produces faithful replicas of a master-pattern with feature sizes down to 100 nm. This well-established EHL process provides additional handles that permit control over the arrangement of the material within the lithographically produced structures.
I am looking at several hierarchical pattern replication methods, demonstrating the creation of functional thin films with three-dimensional design patterns. Examples include successful structure control in semiconducting polymers, block-copolymers, and polymers loaded with carbon nanotubes. In addition to the control over the distribution of optoelectronically active materials in thin films, our research explores how nanometre-sized conducting domains within these materials can be aligned. Current research in the group focuses on integrating EHL generated nano-structures with medicine, which opens up a world of enormous possibilities, the surface of which is just being scratched. This includes the use of sub-micrometre-sized design topographies for sensing and point-of-care technologies by means of surface-enhanced Raman scattering.
From interactive diagnostic tools to the formation of molecular systems that are strikingly similar to living systems providing the basis for the regeneration and lightweight portable technologies with enhanced capabilities, the weaving of nano-structures into everyday materials opens up a world of opportunities.