molecular beam epitaxy

["M. Woo" <melissa@zelda.ehs.uiuc.edu>]

Is anyone else out there dealing with electron molecular beam epitaxy
units (MBEs)?  

Since electron microscopes have been reclassified by our state
regulatory agency from being radiation producing equipment to
"electrical equipment that is primarily not intended to produce
radiation," I was wondering if the MBEs could be similarly exempt from
registration/inspection.  It looks like our x-ray photoelectron
spectrometers (XPS) and Auger electron spectrometers (AES) have dropped
off of the registration/inspection list as well.

The typical voltages used by our MBEs are small compared to the
electron microscopes we have on campus.  However, the currents involved
are significantly higher than the majority of electron microscopes on
campus (though they are in the same range as our XPS units).  (9-10.5
kV, 50-70 mA)  These units are used to deposit one-atom thick layers of
elements to grow crystals and thin films.  The target materials for
these units are not metallic, there are no turns in the beam channels
and beam controls are interlocked to system vacuum gauge controls. 
Past surveys have exhibited no x-ray exposures detectable above
background.

Comments?  Ideas?  My e-mail address is below.  Thanks in advance!

--
Melissa Woo, Health Physicist                    |m-woo@uiuc.edu
University of Illinois at Urbana-Champaign       |ofc 1.217.244.7233
DEHS, MC225, 101 S. Gregory St., Urbana, IL 61801|fax 1.217.244.6594
http://www.uiuc.edu/ph/www/m-woo                 |