Numonyx
has taped out a 1Gbit phase change memory, according to the
company's CTO, Ed Doller.
"We've taped out a 1Gbit phase change device on 45nm", said
Doller. He conceded that the density level is "well below floating
gate" densities, which are currently at 16Gbit, but added that the
next generation of process technology, which Numonyx will be on
next year, will deliver a 4Gbit to 8Gbit memory.
That, of course, could change if Numonyx masters multi-bit per
cell technology. At last year's ISSCC, Numonyx demonstrated a
2bit-per-cell phase change memory but, said Doller: "The key thing
is to implement it with the same performance as single bit per
cell." And that cannot, yet, be achieved. Doller declined to say
when he expects the problem to be solved.
Phase change represents Numonyx's future because it is thought
that floating gate technology will start to become impractical at
32nm.
"Our view is that it's scalable for NOR to the 32nm node", said
Doller.
Asked if he thought that Spansion's Mirrobit could be scaled
further than that, Doller replied: "Floating gate and Mirrorbit
will run out about the same time. Fundamentally it's about how the
devices programme."
On the other hand, phase change has about five generations to
run. "IBM's research labs have produce chalcogenide cells with 5nm
features", said Doller, "they have determined that the technology
will work at 5nm."
Numonyx, whose name was widely assumed to be derived from
Ovonics Unified Memory the technology pioneered by Stanford
Ovshinsky, has been selling 128Mbit phase change memories for a
year.
"We sold our first phase change parts for revenue last year,"
said Doller, we're working with over 20 customers who have had
samples. Phase change is good for some applications."
Like which ones? "Like in servers to replace DRAM", replied
Doller.
Yesterday Numonyx announced what could be its penultimate
generation of floating gate flash chips, a 1Gbit MLC NOR device
made in 45nm technology which is being made in its Israel fab, the
old Intel Fab 18. The chips are being sampled now and will move
into volume production next year, first for wireless customers,
then for general customers.
The 45nm NOR memory uses a self-aligned contact approach which
allows the continued scaling while maintaining backward
compatibility.
So the 45nm NOR chips are drop-in compatible with Numonyx's 65nm
NOR flash chips which allows cellular OEMs to reduce development
costs, extend the life of current platforms, and bring new products
to market faster.
"Numonyx engineers overcame major scaling limitations by
developing new process techniques to produce the 7th generation MLC
NOR flash on the industry's most advanced 45nm technology," said
Doller.
See also: Mannerisms, the blog of David
Manners. Updated twice daily, it's the distinctive, entertaining,
authoritative and never dull commentary on the semiconductor
industry, from someone who knows.
Sign up for the Mannerisms
eNewsletter.