Plasmon Printing: Lithography of Nano-features
with Micro-light
One of the biggest challenges to the
future of integrated circuit and other
microdevice technologies is lithography—the
process by which features are printed
in make tiny integrated devices.The
minimum feature size that can be obtained
using standard projection lithography
is determined by the diffraction limit,
and to reach finer dimensions recent
research on lithography has largely
focused on creating light with shorter
wavelengths use "extreme ultraviolet"
photon sources, at enormous development
and unit costs. The researchers in
the Mesophotonics seed project recently
developed a new lithographic approach
called "plasmon printing" by which
ordinary visible light and conventional
photoresist can be used to print nanoscale
features. The method relies on the
highly localized intensity enhancement
near metal mask features when they
are illuminated by light at a wavelength
resonant with the plasmon frequency
of the metal mask. According to postdoctoral
researcher Pieter Kik, "plasmon printing
beats the diffraction limit for lithography
by using the mask to gather light
intensity and put it where it's needed
to print nanoscale features".
Snapshot of 410 nm light intensity
in a simulated mask of 40 nm Au features
on 25 nm resist layers on glass illuminated
at glancing. Enhanced exposure is
observed in an area with a diameter
< l/20.
For further information, please contact
Professor Harry Atwater, team leader
of Seed 1: (626) 395-2197 or haa@caltech.edu.
