High resolution e-beam lithography using a thin titanium layer to promote resist adhesion

Abstract

This paper describes improvements in high resolution large area e-beam lithography when a thin titanium layer is applied to substrates prior to the application of resist. The technique is particularly useful when there is a requirement to pattern long unsupported nanostructures such as lines which are more than a millimetre long but have widths of less than 20 nm. Such feature sizes are now readily achieved using the most advanced e-beam lithography tools which can have patterning writing fields in excess of one millimetre and spot sizes of less than 5 nm. In this paper, we describe a simple technique to improve the adhesion of different resist structures, particularly on III–V materials to enable the rapid evaluation of high resolution e-beam lithography and we show that X-ray photoelectron spectroscopy (XPS) can be useful in understanding substrate-resist interactions.