Chery also discussed the announcement that ST would be
offering phase-change memory as an embedded non-volatile memory option
for some of its 90-nm microcontrollers. The technology is being
prototyped at the 90-nm manufacturing node during 2013, said Chery had
told analysts at the one-day conference on May 16.
node is for us to prepare for 28-nm. NOR flash is not compatible with
HKMG [high-K metal gate processes]," said Chery, referring to the
details of 28-nm manufacturing process. He added that the current
version of the PCM technology has some thermal limitations. "To keep
performance after reflow [soldering of components] we need different
material. We will be ready at 28-nm," he said.
For these reasons
ST will offer PCM-based microcontrollers at 90-nm for secure and a
general-purpose applications but not for automotive. At 40-nm NOR flash
will continue to provide the non-volatile memory across all application
categories before being replaced for all categories, including
automotive, by PCM in about 2016 or 2017.
Chery told EE Times
that while the initial embedded PCM introduction would be subject to
thermal limitations the company is making progress on finding ternary
mixes of elements that would have improved performance at high
temperature. Chery said that beyond 28-nm it was not clear what would prevail by way of an embedded non-volatile memory technology. "The 40-nm node will have a long life time as will the 28-nm node," Chery said.
Despite working on 90-nm as a development vehicle
for an improved embedded-PCM at 28-nm, Chery said ST would be glad to
supply samples to customers in 2014.