The National Geo TV station presented a program about ‘super
diamonds’ last night.
Super diamonds may replace silicon in many current applications.
Diamonds, i.e. blue diamonds, with a certain amount of boron will
conduct electricity; the majority of diamonds will not. Silicon is
useful to about 300 to 350 degress; diamond to about 2000 degrees.
Scientists have developed diamond in sheet form. I believe the
dimensions were 6’ in diameter by 1/20’ thick were mentioned.
Wouldn’t that be fun to play with. A lot of this work was done in the
U. S. Naval Lab in D C. And if this has been made public they are
much further along in the process.
The down side: the narrator discussing the use of ‘superdiamond’ in
communication devices said, 'just think of what this will do on the
battlefield. It’s pathetic that this is the ‘default’ position.
Please no complaints about the accuracy of my facts. I’m not a
scientist; so watch it yourself. These programs are frequently
repeated. You might find it interesting. It was better than the
Oscars.
The National Geo TV station presented a program about 'super
diamonds' last night.
The part I found especially interesting was how much more durable
they are compared to natural mined diamonds. The reason was that for
the vapor deposition type, where they’re growing those big, but thin,
films, the starting point is a dusting of tiny seed crystals on which
the resulting film grows as the growth on the seed crystals (perhaps
a very fine grade diamond grit?) intergrows to form not a single
crystal, but a structure that sounded like it would compare to
natural diamond, the same way chalcedony compares to single crystal
quartz. The intergrown random orientation means there are no longer
cleavage planes, for one thing, to worry about. It sounded like it
actually results in an increase in hardness too, and perhaps a
substantial one. Interesting, if true. One always has to account for
the fact that between what the narrator says on such shows, there’s a
filter of copywriters and producers and others between that final
narrative and the original expert source of the info, so sometimes
things get emphasized or mistated. Still, interesting.
And then there was the bit about how they grew super strong diamond
anvil crystals for the high pressure equipment. That was puzzling
too. They said they also used chemical vapor depostion to grow a seed
crystal larger, then used high temp/high pressure treatment to make
it further more durable, dense, hard, or whatever. The image on the
screen showed what looked like a transparent crystal. It would need
to be, actually, in order to observe what is happening between the
diamond anvils in the experimental work done. But it leads me to
wonder whether that crystal is still a polycrystaline structure, or
if it differs from natural diamond crystals in some other way.
Definately interesting stuff.
Norton was showing off 6" diamond discs at SemiCON West 10 years or
so ago. I’m sure by now they’re growing them much larger – probably
at least 12" and likely up to 16"
The Japanese were demonstrating diamond transistors at least that
long ago. Don’t know if anyone has demonstrated diamond based ICs by
now.
However you have “diamond-like” films in your computer. Almost all
disk drive platters are coated with the stuff.
Fascinating field. I wonder how much longer before it slops over
into our neighborhood.
I did not see the show, but what is referred to as “super diamond” is
the diamond synthesized from Carbon 14 isotope. Due to 2 extra
neutrons it is harder than regular diamond. One drawback in regular
use is that Carbon 14 is radioactive.
I think the commercial aspect gets in the way of science. But at
least I didn’t notice anyone in jeopardy in this program. One thing I
alluded to was a gap between what those guys at the Naval Lab know
and that which the public is allowed to know. I was in the USAF and
occasionally we saw training films about aircraft that demonstrated
that gap between what the USAF already had on line, etc.
I did not see the show, but what is referred to as "super diamond"
is the diamond synthesized from Carbon 14 isotope. Due to 2 extra
neutrons it is harder than regular diamond. One drawback in
regular use is that Carbon 14 is radioactive.
While this may or may not be the case, that sort of “super diamond”
was NOT apparently mentioned in the show at all. There may be such
an animal (I don’t know), but what was referenced in the show was
diamond produced either from ordinary graphite as the carbon source
in the case of high temp/pressure stones such as from Gemysis, or in
the case of chemical vapor deposition, the source was reacting
hydrogen with methane (I think. Might have been another hydrocarbon
gas) under low pressure and high voltage, or something like that, to
disassociate the carbon from the hydrogen, leading to carbon
deposition on seed crystals. Nothing mentioned about any particular
isotopes, and a radioactive end product would be somewhat less
useful given the intended uses for the stuff…
And if you’re interested in synthetic diamonds as transistors:
The prospect of diamond transistors moves closer as LCN and DMD
sign contract
6 February 2008 Source: london-nano.com
Diamond Microwave Devices Ltd, DMD has placed a contract with
the London Centre for Nanotechnology (LCN) for studies related
to diamond's electronic properties.
DMD, a subsidiary of Element Six which is the world leader in
the production of all forms of synthetic diamond for industrial
use, is actively working on a new generation of electronic
components based on diamond rather than silicon. This work moves
the prospect of active switching needed for RF components closer
to reality. "The work will be to investigate the mobility of
delta-doped chemical vapour deposition (CVD) diamond and to
apply the results within a 2D physical model for a diamond
transistor," explains Richard Lang, general manager of DMD
Ltd.Image of electronic grade diamond which forms the basis of
the transistor research work
Delta doping is a technique that has been proposed to enable
active electronic devices such as MESFETs (MEtal Semiconductor
Field Effect Transistors) to be fabricated in diamond. In this
technique, a thin layer of highly boron-doped diamond buried
within the intrinsic diamond donates carriers (holes) to create
a conduction channel between the metal source and drain. Such a
design approach is needed because only p-type dopants are
currently feasible for diamond and so efforts have been focused
on novel structures that can create the active switching needed
for transistor function taking into account this factor.
DMD's contract with the London Centre for Nanotechnology is to
investigate mobility of delta-doped material. Mobility gives a
measure of the efficiency of a transistor's function and the
study will give an indication of diamond's possible performance
as an active device. The London Centre for Nanotechnology is a
multi-disciplinary organisation at the cutting edge of science
and technology that is involved with research at the nanoscale.
Dr Richard Jackman, who will lead the research at the LCN, says,
"Diamond offers enormous potential for high performance devices,
but brings with it some challenges that are new to the
electronics sector. The experience within DMD, when allied to
the broad range of capabilities of the London Centre for
Nanotechnology, makes this exciting collaboration unique in the
world.
DMD was set up in late 2006 with the aim of creating the next
generation of high power, high temperature semiconductor devices
based on single crystal CVD diamond for use primarily in
microwave power amplifiers and transmitters that are used in a
broad range of applications spanning electronic defence and
communications.
For more on DMD Inc. please visit
http://www.diamondmicrowavedevices.com