Displacement Talbot Lithography: accelerating a versatile and low-cost patterning technique for precision manufacturing

Over the past 50 years, society has benefitted from electronic devices getting smaller and smaller. The challenge of making such small devices has meant that the processes have increased dramatically in cost, to the extent that the latest 'printer' of very small features costs up to $100M. Only a small number of high-volume products can sustain such a cost. Nevertheless, new physics can occur, and materials can have novel properties at the smallest scales - the nanoscale. So, for society to use these more widely, we need to develop cheaper ways of making small materials and devices. Otherwise, they are unviable, and research into the opportunities that they provide will be limited.

This proposal is about extending a recently developed technique called Displacement Talbot Lithography that uses the interference of light to make very small patterns. We will then combine it with other processes, such as atomic layer deposition that allows materials to be controllably coated with individual layers of atoms, to further decrease the pattern size. The technique is exciting because it combines low-cost with high yield and can be scaled relatively easily to large areas, to further increase manufacturability; important for them to be produced at the scale to be used in society at large. Being a new technique, its potential is still relatively unknown.

We will then apply the patterning technique to the manufacture of advanced materials that can combine conventional electronics based on silicon with optical communications. Whilst silicon is a mature material for making electronics, it manages light poorly. By growing crystals of good optical materials such as indium phosphide directly on silicon we will combine the optimum properties of both materials to make an engineered super-material. But this can only be done cost-effectively by using the very fine patterning that is possible with Displacement Talbot Lithography.

To achieve these goals, the University of Bath and Cardiff University are combining their expertise and working together. Researchers at Bath are experts in large area nanofabrication whilst those at Cardiff are experts in growing group III-V semiconductor crystals for use in optical communications. We will also be partnering with UK manufacturing industry who have the interest and ability to exploit the results and have the wider industry connections to pass on the benefits up the supply chain: Newport Wafer Fab is an advanced semiconductor processing facility that currently boasts International Rectifier, Motorola, Samsung, STM as its clients, whilst PragmatIC Semiconductor is a world leader in ultra-low-cost flexible electronics.