Diamond is the hardest known material.
It also has the highest sound
velocity,
it has the highest electron and whole mobilities,
and that's what makes it a better electronic
material.
It has the highest atomic number
density of any material known to man
outside of a neutron star
and that's what gives it
uh... these amazing properties.
The newest diamond in the world.
For a long time, diamond uh... was
thought to only form under high pressure
and temperature
Well, the first time I came into uh...
contact with this idea of growing diamond
at low pressure
and low temperature was when I came
across the work by John Angus, who was at
Case Western. He was ridiculed for that
idea
because people had assumed that
based on the pure carbon phase diagram
that diamond will never grow at low
pressure
and low temperature.
People had looked at the pure carbon
phase diagram and saw that diamond was
unstable at low pressure and low
temperature
and they extrapolated from that
to all systems
and whenever uh...
anyone presented work of diamond
being formed at low pressure and low
temperature
uh... people presented uh... the carbon
phase diagram--the pure carbon phase diagram
as evidence why that could not
happen.
The error there is that
what we're doing is not using a pure
carbon
situation.
We're actually uh... using carbon with
hydrogen
In our specific case, we use plasma
to
dissociate hydrogen to atomic hydrogen and plasma is
another state of matter entirely and
is not normally represented in a phase diagram.
We think the atomic hydrogen
that's formed by the plasma is able to
preferentially etch
the graphitic bonds
thereby enabling the system to form
diamond instead of graphite.
And so if you look at the energetics of
the situation
the system gains a lot of energy by
depositing carbon
from a carbon-hydrogen mixture and that is
given by the phase diagram.
You start with a diamond seed.
You place that in your chamber. You then
evacuate the atmosphere then we feed it
highly pure gases of methane and hydrogen.
There can be other sources of carbon
to the mixture. We...
we just chose methane and hydrogen.
In fact, it's been shown, we can make
diamond out of whiskey
or any other material that has carbon.
Diamonds are already making an
an impact on the highest
performance of detectors;
particle detectors, and radiation
detectors for example used in the
large hadron collider. We'll see a
transition from these early applications of
electronic diamond into
more commonplace devices such as maybe
power handling, power switching
devices
but unfortunately, we still have to wait
a while before we see it in things
like PCs and cellphones.
Well, these are
single-crystal diamonds that we've grown
and that's sent to a
traditional gemologist
to cut into gems. So this is called an
American standard
cut or a brilliant cut.
And it is equivalent to
the gem that you find in the ground,
except it was made right here in the
lab!
It's very exciting to be able to
be in a position to launch this material
that is
of outlandish properties Whenever we
measure diamond,
it has astonishing properties that are
just much higher than anything else
and it's never been available as an
engineering material before
so we're at...
starting to be able to utilize these
properties to enable them to come into
the marketplace.
