Fred, I agree that the OUM probably will be a very big winner for us. I have felt this for some time but had no specifics until the OUM addition to our web site appeared.
I am trying to come up to speed on our memory chip technology, and our competitor's tech as well. Not there yet, by any means; but as luck would have it I opened a copy of a several-months-old Science magazine in the "John" this a.m. (my, uh, contemplative reading for decades now); and saw a paper on Spintronic technology. However, my bowels were faster than my brain and I only had time to skim the article. That smattering of info, plus the article below, and some odd things about the present ECD Web presentation of the OUM lead me to some comments.
Remember (a) that the ECD Web Site stuff on the OUM looks like a slide presentation, (b) it stands to reason that Tyler Lowery must be making presentations to people who would also be interested in the Spintronic memory developments, and (c) Tyler has been heavily emphasizing some aspects of the OUM. I think he is making some compelling comparisons, specifically against the Spintronic devices - my speculations about this are as follows (and please remember that I am throwing some things out for further scrutiny, not laying out gospel).
The Spintronic switch (i.e., a memory cell) is touted (see article below) as "could hardly be simpler". However, the Ovonic switch is simpler yet! Not counting the substrate layer and any protecting overcoat layers, here is what I think each device requires in the way of layers of materials. (Essentially, each feature of a chip device is formed from a layer that is then pattern-etched). The spintronic device has inherently five or six layers - three for the switch, two for the read wires (which are on opposite sides of the switch surfaces), and one or two for the write wire(s). The Ovonic switch has inherently only two layers - one layer for the switch and only one layer for the two wires (because they are on the same side of the switch layer) that serve both read and write functions. Tyler is emphasizing the EXTREME simplicity of the OUM, and we clearly win this important point.
Spintronic memories can be fabricated using present chip making facilities. So can the OUMs - and even more simply! We win again.
Spintronic memory cells are fast. However, I have seen no number less than 10 ns mentioned for the Spintronic switch. The OUM cells are only 1 ns!. We win again, on a key point.
The Science magazine article brought out that, for one version of the Spintronic switch at least, the resistance increases rapidly for smaller cell size - so very small cells are difficult or impractical. Further, the resistance change mentioned is only 30%. Now we can see why Tyler is emphasizing the OUM works even better for smaller cells - and we have such a large resistance change that up to 16 levels can be used. We can store a byte rather than a bit - in very small cells! We win big, on a key point.
As nearly as I can tell, we also give up nothing with regard to ruggedness/temperature-range/radiation-resistance. And our ten year non-volatile memory capability would be hard to beat, IMO.
It seems incomprehensible that several companies would not be beating down ECD's doors, bearing huge sums of money. However, to quote Mark Johnson from the following article:
<<Despite being the father of spintronics, Johnson is also keen to play
down the hype. His own experiences lead him to suggest that the
major barrier preventing spintronics really taking off is not
technical, but psychological. "For my devices, the biggest problem
has been a reluctance among the semiconductor community to get
involved in what they see as 'disruptive' technology." He also
believes that there is a reluctance among other companies to get
involved in technologies they haven't seen before. Johnson calls it
"the 'not invented here' syndrome." >>
Thanks for confirming a long-held suspicion of mine, Mark. But, IMO, ECD is going to win anyway!
The following is from: science-books.com
TAKE A SPIN 28 Feb 98
(Copy of selected material. "Johnson" is Mark Johnson of the US Naval Research Laboratory)
A spintronic switch could hardly be simpler,
comprising of a layer of highly conductive gold sandwiched
between two thin films of ferromagnetic material.
Unpolarised electrons sent into the first thin film adopt its mix of
spin-up/spin-down varieties, and then zoom across the "filling" of
gold before running into the second ferromagnetic film on the other
side. Whether they get any further depends on their spin. Only
those with spins that are aligned to the magnetic field of the film can
continue on their way. Effectively, the second film behaves like a
spin filter, with the size of the current that can pass depending on
the relative numbers of spin-up and spin-down electrons created by
the first strip. "It is similar to crossing and uncrossing polarised light
filters, but the analogy is not strictly the same," says Johnson (see
Diagrams, file sizes aprox. 35K).
Flash memory
Flipping the switch from off to on--or, in digital terms, from 0 to
1--is then simply a matter of altering the magnetic orientation of the
second strip from up to down. This can be done by passing a
current through a small wire on top of the ferromagnetic film. The
current generates a magnetic field strong enough to flip the
orientation of the ferromagnet.
These switches are causing particular excitement among electronics
researchers because they can store information. Ferromagnetic
materials behave effectively like small permanent magnets, and
once their field orientation has been flipped, they stay
flipped--giving a way to store 1s or 0s without the need for any
external power. They can be used to make incredibly fast yet
"nonvolatile" electronic memories that faithfully retain their content
even after the power has been switched off. Reading the data is
simply a matter of passing current through a switch to see whether
it is set to on or off. "The only silicon device that can do this is the
so-called flash memory cell," says Johnson. "But that takes
milliseconds to store data--a million times longer than spintronic
devices."
Spintronic memories are even able to cope with intense radiation,
because the magnetisation of their ferromagnetic films is unaffected
by charged particles that would trash the components of
semiconductor devices. What's more, says Johnson, spintronic
switches consume far less power than semiconductor switches,
allowing far more of them to be crammed together without fear of
overheating. Even the semiconductors in ordinary desktop PCs are
liable to overheat.
It is this unique combination of abilities that has made the US
Department of Defense take spintronics very seriously indeed. Over
the past 18 months, DARPA has poured more than $50 million into
spintronics research at commercial and academic centres throughout
the US. "Satellites were the primary motivation, but there are many
other military systems that need nonvolatile, extremely
environmentally robust memories," says Stuart Wolf, who manages
the DARPA programme. "Their commercial potential as faster,
lower-power replacements for flash memory also makes them
attractive to us." If spintronic chips can be produced commercially
they will be cheaper for everyone.
The objective of the DARPA programme is to make spintronic
memory devices that have the speed and storage capacity of the
very best conventional semiconductor memories. The bulk of the
funding has gone into exploiting the phenomenon known as giant
magnetoresistance (GMR), in which devices with many
ferromagnetic layers are used to control the flow of the spinning
electrons through them ("Giants in their field", New Scientist, 10
February 1996, p 34). According to Wolf, progress so far has been
rapid. "Honeywell has demonstrated a fully functional 16-kilobit
memory with an access time of less than 100 nanoseconds, and is
well on its way to a 256-kilobit memory," he says. "Motorola's and
IBM's research efforts are also proceeding very well, and they're on
target to have some devices to demonstrate by the end of this
summer."
Semiconductor sandwich
PC users may start to benefit from this startling progress early in
the next century. "Spintronic devices would allow us to replace the
redundancy and cost of having two memory systems--RAM
[random access memory] and hard discs--by a single, fast spintronic
device that does the work of both," says Johnson. Accessing data
on a hard disc is a time-consuming business. This is why computers
take so long to boot up. With a spintronic memory, they would be
ready to work almost immediately. "Making these devices is pretty
simple, and people are talking about making 1 gigabyte of
nonvolatile RAM for the same cost as today's 1-gigabyte hard
drives," says Johnson. That is, for well under $200.
Permanent memories look set to be the first commercial spintronic
devices, but some research teams are investigating other ways to
exploit electron spin. At the California Institute of Technology in
Pasadena, Michael Roukes and his colleagues are experimenting
with spintronic devices made from both metals and semiconductors.
The Caltech approach is to put a semiconductor "filling" between
the two ferromagnetic films in the spintronic sandwich. The plan is
to exploit the fact that electrons trapped inside the specially
constructed semiconductor layer encounter very few impurities, and
thus behave like the particles of a gas. Being able to move around
more freely, this should make them much more responsive to
incoming signals, allowing them to be made smaller.
In particular, it should make possible hybrid spintronic transistors
made from metals and semiconductors that can be packed together
far more tightly than they can in today's equivalents. This is hugely
significant, since spintronic devices made from semiconducting
materials could easily be manufactured in today's chip factories.
New manufacturing plants would cost billions of dollars to build.
"To begin with, spintronic transistors will probably be most
interesting as nonvolatile memory devices integrated into
microprocessors," says team member Franklin Monzon. "Later on,
they might find applications as logic elements as well." But just how
much further spin-based electronics will go is still unclear, says
Monzon.
One worry is that much of the work on semiconducting spintronic
devices has been carried out at temperatures only a few degrees
above absolute zero. "The spin of the electron is an inherently
quantum phenomenon, and it's more easily manipulated at low
temperatures, where effects that would otherwise interfere with spin
dynamics, such as scattering, are frozen out," explains Monzon. "A
device barely operating at 4·2 kelvin would likely just not work at
all at room temperature, he says. The big challenge ahead for
researchers is to find a way of applying what they have learnt at
low temperatures to devices that will function at higher
temperatures. The fact that the metal spintronic memories retain
their impressive abilities at room temperature provides grounds for
hope.
Great expectations
Even so, Monzon sees other problems ahead. "The biggest are
material and interface problems," he says. "For example, it's still not
clear what combination of materials we need to best control the
behaviour of the electrons inside these devices."
Despite being the father of spintronics, Johnson is also keen to play
down the hype. His own experiences lead him to suggest that the
major barrier preventing spintronics really taking off is not
technical, but psychological. "For my devices, the biggest problem
has been a reluctance among the semiconductor community to get
involved in what they see as 'disruptive' technology." He also
believes that there is a reluctance among other companies to get
involved in technologies they haven't seen be-fore. Johnson calls it
"the 'not invented here' syndrome."
But Johnson thinks the rapid progress made in spintronics speaks
volumes for their potential. "The devices we're working on have a
research investment of only a few person-years, yet we already
have prototypes that are competitive in terms of size and speed with
silicon devices which have had tens if not hundreds of thousands of
person-years of research invested. For a fledgling field, we think
we're doing well."
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