Triblock Terpolymers for Self-assembled Nanolithography

Self-assembly provides the ability to create well-controlled nanostructures with electronic or chemical functionality and enables the synthesis of a wide range of useful devices. Diblock copolymers self-assemble into periodic arrays of microdomains with feature sizes of typically 10-50 nm, and have been used as self-assembled 'resists' to define periodic patterns useful in making a wide range of devices such as silicon capacitors and transistors, photonic crystals, and patterned magnetic media. However, the lamellar, cylindrical or spherical microdomains in diblock copolymers generally form grating patterns, or close packed structures with hexagonal symmetry. This limitation in pattern geometries restricts their device applications, making it desirable to create self-assembled patterns with a wider range of geometries and applications. The intellectual merit of this proposal is the development of triblock terpolymers which form thin films with a diverse range of geometries. The work includes design of triblock terpolymers to form films with specific geometries such as widely or closely-spaced lines, lines with specific edge modulations, junctions, or bends, or arrays of cylinders or spheres in non-close-packed arrangements; synthesis of polymers with appropriate block chemistry, interactions and volume fractions; understanding processing effects including substrate treatment and annealing processes; modeling the self-assembly; and generation of magnetic nanoparticles within one block to form functional nanostructures directly. Central to this work is an investigation of templating of triblock terpolymers using substrate chemistry and topography, so that the self-assembly can be guided to nanoscale precision. The work is a collaboration between a group in Bristol, UK, with experience in the synthetic chemistry of triblock terpolymers, and a group in MIT, Cambridge MA, with experience in block copolymer lithography and templating.

Who will benefit from this research? How will they benefit from this research? The project is a collaboration between the Manners group in Bristol, UK, with expertise in block copolymer synthesis, and the Ross group in MIT with expertise in processing, templating, and etching of block copolymer thin films and their application in nanolithography. This work will contribute to our understanding of how to use self-assembled polymers in sophisticated pattern generation and device fabrication processes. The work is therefore of potential long term benefit to UK.plc and the general public through improved technology (as well as to academic science, as discussed elsewhere). It is also envisaged that broad interdisciplinary scope of the project and the use of materials and property characterization techniques will give a Ph.D. student exceptional training for their future career. This is likely to be in industry or government labs (or, as an alternative, academia). These employers and the Ph.D. student will also therefore be substantial beneficiaries from the training provided by the proposed research. What will be done to ensure that they have the opportunity to benefit from this research? The research results will be reported in top scientific journals and at Universities, Industries, and conferences by Manners, Ross and the Ph.D. students to be hired. Industrialists and government lab representatives regularly target meetings at the chemistry / polymer / materials science interface. Track record: Both Manners and Ross have strong track records for high profile research. For example, with a focus on the UK side of the collaboration for this EPSRC proposal, Manners has a track record for publishing in top journals (e.g. 7 papers in Science and Nature journals and 40 in Journal of the American Chemical Society since 2000) and delivers a large number of invited lectures annually internationally and in the UK (e.g. 26 lectures in 2008, including 7 international plenary lectures and 3 distinguished lectureships). In addition, all students and postdocs in his research group present orally at top conferences, and these are often outside the UK. Manners also lectures regularly at companies. Manners has also organized workshops in several areas to engage the user community (aircraft and automobile companies) on topics such as luminescent polymer sensors for air-pressure. The Ph.D. student trained by performing the proposed research is likely to find an excellent future position as Manners group has an outstanding record in training personnel Track record: The 47 former Ph.D. students and Postdocs trained in the Manners research group now occupy positions on academia or industrial / government laboratories in the UK, Canada, the USA, China, Taiwan, Japan, South Africa, Germany, and Spain. Over 100 masters and undergraduates have also worked in the research group since 1990. Many have gone on to complete PhDs at other institutions and now occupy prominent industrial or academic, or important societal positions, such as high school teaching.