Charged particle single nanometre manufacturing

Following a brief historical summary of the way in which electron beam lithography developed out of the scanning electron microscope,three state-of-the-art charged-particle beam nanopatterning technologies are considered. All three have been the subject of arecently completed European Union Project entitled “Single Nanometre Manufacturing: Beyond CMOS”. Scanning helium ionbeam lithography has the advantages of virtually zero proximity effect, nanoscale patterning capability and high sensitivity in combinationwith a novel fullerene resist based on the sub-nanometre C60 molecule. The shot noise-limited minimum linewidthachieved to date is 6 nm. The second technology, focused electron induced processing (FEBIP), uses a nozzle-dispensed precursorgas either to etch or to deposit patterns on the nanometre scale without the need for resist. The process has potential for highthroughput enhancement using multiple electron beams and a system employing up to 196 beams is under development based on acommercial SEM platform. Among its potential applications is the manufacture of templates for nanoimprint lithography, NIL. Thisis also a target application for the third and final charged particle technology, viz. field emission electron scanning probe lithography,FE-eSPL. This has been developed out of scanning tunneling microscopy using lower-energy electrons (tens of electronvoltsrather than the tens of kiloelectronvolts of the other techniques). It has the considerable advantage of being employed without theneed for a vacuum system, in ambient air and is capable of sub-10 nm patterning using either developable resists or a self-developingmode applicable for many polymeric resists, which is preferred. Like FEBIP it is potentially capable of massive parallelizationfor applications requiring high throughput