BUILDING ON THE PAST, READY FOR THE FUTURE: - MEMC

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Dr. roberT fAlSTer: in hiS oWn WorDS
In April of 2001, Dr. Robert Falster, Senior
Fellow of MEMC Electronic Materials,
Inc., received the European SEMI Award
for his contribution to the semiconductor
manufacturing industry. He described the work
that led to this award:
“It was an exciting time. The control and
engineering of the precipitation of oxygen
in our wafers during our customer’s varied
manufacturing processes was a huge challenge
and, to a large extent, a mystery. There were
simply too many variables. This resulted
in huge variations in wafer performance.
Decades of work on the problem around the
world had not brought the silicon world much
closer to a robust solution. The solutions
at hand were specific to each and every
application and resulted often in immense
and, ultimately needless, complication and
rigidity at many levels of our business. MDZ
solved all this at a stroke. Research centered
in Novara resulted in our mastery of the
engineering of useful vacancy concentration
profiles in silicon wafers. We showed that
certain depth profiles could be used to act as
a template which takes complete control over
the wafer’s oxygen precipitation behavior and
creates an ideal structure for high yielding
integrated circuit manufacture. These profiles
could be accurately installed in every wafer
resulting in completely uniform performance
beyond. The proprietary knowledge they represent
will continue to ensure MEMC’s position in the
industry for years to come.
PerFeCt sIlICon
Perfect Silicon is MEMC’s proprietary defect-free
crystal growth process designed to completely
suppress the formation of low-density, grown-in
defects. The main principle behind the CZ single-
Dr. Robert Falster, 2006.
in all our wafers. Immensely important was
that we broke the chain of complication
that extended from the growing crystal to
the finished electronic device. We created a
wafer whose behavior was not only ideal but
which could be implemented in a way that
waas independent of all those interacting
components that had bedeviled and tied us
up in knots in the past: the details of the
crystal growth process, the distribution of
oxygen in our wafers and the details of our
customer’s manufacturing processes. This was
a revolution and a relief.”
crystal growing process lies in the rapid transport
of growth-incorporated excess intrinsic point
defects to harmless sinks before they have a chance
to react to form defects. This method of growing
CZ single-crystal controls the point defect level
by preventing clustering as the crystal cools. The
as-grown crystal is free of cluster defects across
the wafer, thereby eliminating the need for postgrowth
engineering such as annealing or epitaxial
growth. Perfect Silicon wafers are 100 percent free