Michael Gruver, Program Manager, IBM Engineering &
Technology Solutions, gives his perspective on foundry
customers and custom SOI design.
Advanced Substrate News: What
tools or investments would a customer
need if they were going for an SOI-based
solution?
Michael Gruver: There are two primary
areas that a customer should address if
they intend to use IBM SOI technology.
The first is SOI-specific design education.
SOI has electrical properties that must be
accounted for such as the “history effect”
and performance variations due to the
“floating body” of the SOI transistor. IBM’s
Engineering & Technology Services (E&TS)
division offers a comprehensive set of
education sessions to train individuals in
the art of SOI design.
The second area is Tools & Methodology.
As industry standard tools cannot directly
simulate SOI floating body effects,
IBM has a specialized simulator called
POWERSPICE that also includes specific
functions for analyzing the history effect.
Static timing closure with SOI requires
special handling. Other more obvious
differences include specialized DRC
(Design Rules Checking). Once again, IBM
E&TS can work with clients to install and
train them in the entire flow of tools used
for custom SOI design.
ASN: Are there broader benefits beyond
the straight performance boost that you
tell your customers about that might make
that investment worthwhile?
MG: SOI wafers are, in fact, more
expensive than bulk. However, there
are other variables that can offset this
cost, such as smaller die sizes and less
complex backend processes. This is
especially the case for high-end chip
designs where you are trying to gain the
maximum frequency.
Of course all of these are trade-offs that
need to be carefully understood and
weighed. IBM E&TS has consulting
services to help you with these decisions.
