NPGS: Cu/Co Wire
This image shows four Ag leads connecting to a Cu/Co multilayer
wire. (The layers are perpendicular to the axis of the wire and can be seen
in the image.) Before the contacts are defined, the sample has many such
wires randomly scattered across the substrate. The challenge is to locate
one wire and connect to it, even though every wire is randomly positioned
and no registration marks are available. A new capability of NPGS has made
it possible to image an individual wire while minimizing the exposure, and
then to write the contact leads at whatever rotation is required. This capability
was developed specifically to help in this application and is now included
in NPGS as a standard feature. This work was done by Dr. Mark Tuominen's
group in the Physics department at the University of Massachusetts in Amherst.