Large Area Scanning-Probe Nanofabrication Platform

Thoroughout history, our ability to manipulate matter has always been one of the cornerstones of human progress, from the synthesis of drug molecules by chemical reactions, to the building of the largest skyscrapers. Currently, there is great interest in nanotechnology, the science of constructing and studying objects at nanometre scales (a billionth of a metre). Research in this area has shown that when materials are reduced down to this size scale, or have alterations to their shape at this length, entirely new properties can arise that are radically different from when they exist in a bulk form. By finding ways of harnessing these unusual properties, new technologies can be developed for improved electronic devices, medical tools and even construction materials.

Further progress in this area, however, requires the extension of our ability to construct objects at this scale over large areas while still maintaining nanometre scale control of the process. Such a capability would enable the production of large networks of nano-sized objects, which would allow new research into how these objects behave in relation to each other, rather than as individual objects on their own. The large area construction would also show how it would be possible to produce many objects at once, which will be important if they need to be made on an industrial scale.

Although large-area high-resolution patterning is possible using methods adapted from the electronics industry such as the processes that are used to make computer microchips, they have a number of disadvantages. They rely on harsh methods, for example high temperatures and corrosive chemicals, that limit the types of materials that can be used. As a result, it is often difficult to produce devices with complex designs made up of different materials. In particular, these methods are not compatible with delicate molecules from biology, such as DNA and proteins.

In this proposal, we wish to set up a type of instrument that uses "scanning probes". Each of these probes consists of a very sharp, nanometre-wide, tip that can be coated with a variety of chemical compounds. The instrument is also able to control the movement of this probe with nanometre precision. Thus, by moving this probe tip across a surface, it is possible to "write" nano-scale patterns by depositing the compound coated on the probe on to that surface. The movement of the probe can be controlled by the user, so it is possible for the user to write complex patterns such as circuits and even pictures.

For this particular instrument, the major advantage over other older designs is that it is able to use many probes, thousands or even millions, simultaneously. In doing so, it is therefore possible to write patterns with a wide range of chemical compounds, over large areas of surface with nanometre control. This would spark new research into many areas of science, from the production of highly miniaturised electronic devices for computing to disease diagnosis; efficient batteries for power storage; and surgical implants that can control the behaviour of tissues and cells.

This instrument will give us the facility to generate any user-defined pattern with a variety of materials over large areas with nanometre resolution. Its generic usefulness will thus have an impact on research in many areas of science and engineering.

It will further our fundamental understanding of the physical, chemical and electronic properties of materials at this scale, which will in turn progress the development of new miniaturised electronic devices (e.g. fuel cells, sensors, diagnostics) to artificial surgical implants and tissues for regenerative medicine. In relation to the latter, the behaviour of human cells and tissues in contact with nanoarchitectured surfaces is relevant to researchers and regulatory authorities who have an interest in determining any potential health hazards of exposure to nanotechnology (i.e. nanotoxicology).

A key characteristic of this instrument is its ability to produce such nanoscale patterns over large areas through the parallelised writing of many probes, which in turn allows the fabrication of many nanostructures simultaneously. This type of "mass production" will offer a means to trial the scaling up of nanolithography towards commercial manufacturing levels, which is particularly important if this type of nanofabrication is to make a meaningful industrial impact. This capability will therefore benefit many companies interested in producing goods that have nanofabricated components. Indeed, the development of such scanning probe nanofabrication systems will be a significant step towards a low cost "desktop fab", which would allow access of a nanofabrication tool to a wider range of industries and researchers in the micro- (and nano-)machining sector for the rapid production and prototyping of nanoscale devices; and would be an alternative to the current high cost, energy intensive fabrication methods derived from the electronics industry.

In order to maximise the impact of this instrument, its user base will be drawn from across the range of scientific and engineering disciplines. In particular, engagement has been sought with a number of research centres and organisations to publicise the availability of this facility and to develop related research plans. These organisations include:
- The North West Nanoscience (NOWNANO) Doctoral Training Centre, based across the Universities of Manchester and Lancaster - To train new students in the use of state-of-the-art scanning probe nanolithography.
- The National Graphene Institute (NGI) - To progress the fundamental science of graphene and to improve the manufacturability of graphene-based technologies.
- The Welcome Trust Centre for Cell Matrix Research (WTCCMR) - To explore the use of nanofabricated surfaces for cellular manipulation, leading to improved therapies for a variety of disorders.
- The UK Centre for Tissue Engineering (UKCTE), based at the Department of Clinical Engineering, University of Liverpool - To develop artificial tissues and implants for therapeutic purposes and tissue analogues as a substitute for animal testing.
- The Knowledge Centre for Materials Chemistry (KCMC), representing NW regional industries - To apply scanning probe lithography for the development of new products and processes that are relevant to the client companies.

More generally, this instrument will contribute to the UK's position as a major participant in the field of nanotechnology. Research in this and related areas will facilitate the exposure and training of a new generation of interdisciplinary scientists in nanotechnology that will be well equipped to harness the potential economic and social benefits arising from their research.