NPGS : 12 nm Line
This is an SEM image of a lifted off wire that has a width of ~12 nm. The
line was written in 70 nm PMMA and metallized with Ti(10 nm)/Au(20 nm). The
work was performed at the Centre for Quantum Computer Technology, UNSW, Sydney,
Note that when making features on this size scale, the grain size of the metal using during liftoff becomes extremely important. For example, if the line width is smaller than the grain size of the metal, it will be impossible to produce a smooth line.
The line was written using NPGS with a thermal FE SEM. Thermal FE SEMs have proven to be the most useful models for SEM lithography, due to their ease of use, high resolution, and stable beam current.
Image Copyright (c) 2003 UNSW, Sydney, Australia.