NANO-LITHOGRAPHY USING A RESIST, PATTERNED BY ELECTRON EXPOSURE IN ANAFM CONFIGURATION

We have used a metallised microscope tip to apply a voltage and thereb y expose a very thin resist film. It is possible to image the film sur face before; during and after the exposure, without interference with the process. Uniform resist films as thin as 10 nm are fabricated usin g the Langmuir-Blodgett technique, To orient the defined pattern and t o make electrical connections a special larger scale alignment structu re is first defined by conventional electron beam lithography, either directly in the Langmuir-Blodgett resist film or in a complete first p rocess with a separate resist system. The results from the one resist process gave conducting 50 nm lines in a 60 Angstrom thick aluminium f ilm after pattern transfer. The two step process, which is aiming towa rds definition of extremely small tunnel junctions for low temperature measurements, have produced similar conductive lines; still though, w ithout tunnelling barriers between the two metal layers.