Newswise — University
at Buffalo engineers are working to solve two significant
roadblocks impeding the creation of smaller, faster
and more powerful electronic devices.
Working atom by atom, Cemal Basaran, Ph.D., and
David Kofke, Ph.D., are taking on the problems of
electromigration and thermomigration -- the tendency
for atoms to behave erratically when charged by the
very high density electrical currents required to
power super-small and super-powerful electronic devices.
Basaran is director of the Electronics Packaging
Lab in the UB School of Engineering and Applied Sciences
and is professor in its Department of Civil, Structural
and Environmental Engineering. A UB Distinguished
Professor, Kofke is chair of the Department of Chemical
and Biological Engineering in the School of Engineering
and Applied Sciences.
High electrical current densities and high temperature
gradients create voids within metal conductors, the
researchers explain. This leads to breakdowns in
circuitry and results in device failure. Moreover,
as electronic devices and their circuits get smaller
-- down to the nanoscale -- the damaging effects
of electromigration and
With the support of a $250,000 grant from the National
Science Foundation, Basaran and Kofke are using computer
simulations and laboratory experiments to devise
ways to lessen or stop electromigration and thermomigration.
Engineers from the Intel Corp. are collaborating
with the UB researchers on the project.
"Once we learn to stop this self-destructive process
in metals, any component in a computer chip can be
made at the nanoscale," says Basaran. "But unless
you solve this problem, you cannot have fast-performing
nanoelectronic devices, and further miniaturization
in electronics may not be possible."
The science of nanoelectronics is focused on creation
of nanoscale circuits, wires and packaging of semiconductors.
The goal of industry is to use these components to
manufacture a new class of very small and very powerful
electronic devices, such as wristwatch-sized supercomputers.
One nanometer is about 1/100,000 of a human-hair
Working at the nanoscale level, the researchers
intend to build semiconductor devices one atom at
a time. According to Basaran, controlling placement
of atoms in a material will give the researchers
precise control of their properties, thus reigning
in the erratic behavior that causes system breakdowns.
"When you design materials at the atomic scale you
get properties you
wouldn't get otherwise," Basaran says. "You get exact properties that
you want instead of what nature dishes out for you. This means you can do things
with a material that you couldn't imagine doing before with the same material."
The goal of the UB researchers is to design nanoscale
chips, circuits and solder joints that can withstand
very high current densities and very high temperature
"High current density changes everything," Basaran
says. "It makes everything faster and more powerful.
If you want a faster computer you
need higher current density."
Today's computers operate at a maximum 1,000 amps
per square centimeter. The UB researchers' work may
one day enable computers to operate with a current
density 1,000 times greater.
The University at Buffalo is a premier research-intensive
public university, the largest and most comprehensive
campus in the State University of New York.