A refined method developed at NIST for measuring nanometer-sized
objects may help computer manufacturers more effectively size up
the myriad tiny switches packed onto chips' surfaces. The
method, which makes use of multiple measuring instruments and
statistical techniques, is already drawing attention from
industry. Nothing in life may be certain except death and taxes,
but in the world of computer chip manufacturing, uncertainty is
a particularly nagging issue, especially when measuring features
smaller than a few dozen nanometers. Precision and accuracy are
essential to controlling a complex and expensive manufacturing
process to ensure the final chips actually work. But features on
modern chips are so tiny that optical microscopes cannot make
them out directly. Metrologists have to use indirect methods,
like "scatterometry"—deducing their shape from sampling the
pattern light creates as it scatters off the features' edges.
When this isn't enough, there's atomic force microscopy (AFM).
It's expensive and sl