Semiconductors open a new niche for plasma researchers

What drives the computer industry is the creation of computer chips with
finer features.  Semiconductor makers are counting on improvements in a plasma 
processing, in which a partially ionized gas is used to initiate the
chemical etching reactions, to drive that progress. 

Most integrated circuits are etched by fixing masks over the wafers and
exposing them to wet acids.  It was time consuming and the acid undercut
the masks.  Plasma based etch tools, (reactors) cut straighter finer
features on chips at once by exposing masked semiconductor wafers to a partically 
ionized gas that includes a reactive component like fluorine.  Attracted by an electric
charge on the wafer, the plasma ions rain down, tearing apart atomic bonds and
pumping energy into the crystal lattice.  The fluorine then react with the
silicon and form silicon fluoride gas, which diffuses away.  The result is
chips that are more tightly packed and cheaper memory and logic circuits .
Plasmas ushered in the personal computer revolution.


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Closing in on Cosmic expansion
Supernovas , giant stellar explosions visible far out in the expanding 
universe may finally be breaking a decades long impasse over the elusive hubble constant.

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LEP up to higher energies

Supersymmetric theories suggest that an abundance of new particles is waiting
to be discovered.  

CERN's large electron-positron collider (LEP) began a month long
run at 130billion electron volts (GeV).  
See <a href="http://hpl3sn02.cern.ch/130GeV.html"> LEP experiments </a>
A 131 GeV Electron positron collision at LEP spawns a photon and a 
massive Z boson which prompt annihilates in showers of other 
particles.

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Naked Quasars get dressed
Hubble space telescope looked at quasars are believed to be 
black holes fed by gas and stars from large host galaxies.  Many 
of hubble images show "naked" quasars, shining outside any 
host galaxy.  But hubble showed that they may not be naked
after all.


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The chemistry of Size and Order on the Nanometer scale

For nanocrystalline materials a modification of the size or shape of
the crystallites may effect an equivalent change.  Many fundamental
properties of materials are characterized by length scales of 
10-200 Angstoms.  If a crystal is fabricated with a length scale
of some property that property is "confined" and is dependent on the 
size and shape of a quantum crystal.

Murray, Kagan, and Bawendi report a step to achieving
the self assembly of quantum structures into more complex 
arrangements.

In semiconductor nanocrystals spectacular effects are seens
with 3D exciton confinement.  Leading to discrete, excited
electronic states with high oscillator strength and to band gaps that
increase as an inverse function of crystallite size.  In certain cases
finite-sized structures may exhibit fundamentally new properties.

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Self organization of CdSe Nanocrystallites into 3D Quantum Dot
superlattices

The self organization of CdSe nanocrystallites into 3D semiconductor
quantum dot superlattices (collodal crystals ) is demonstrated.  The size
and spacing of the dots within the superlattice are controlled with near atomic precision.  This control is a result of synthetic advances that provide
CdSe nanocrystallites that are monodisperse within the limit of atomic
roughness.  The methodology is not limited to semiconductor quantum dots
but provides general procedues for the preparation and characterization of
ordered structures of nanocrystallites from a variety of materials.

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