الفهرس Only 14 pages are availabe for public view
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Abstract
An electron gun of a pentode type has been used to produce Auger
electrons for a surface elemental analysis. The optical parameters affecting the
primary electron beam have been studied. The results have been used to
optimize electron beam current and beam focus position. The technological
aspects and the operation of the electron gun have been experimentally
illustrated. The experimental study has been made for electron beam diagnostic
as a primary beam for Auger electron spectroscopy in a field free region. The
trajectory and the electron beam profile are experimentally studied and
illustrated at different positions from the gun anode. A security device for
cooling systems is designed and constructed against hazardous failure of water
cooling and/or electrical mains supply in order to prevent damages of the high
vacuum pumps and to provide better operating condition.
A retarding field analyzer has been used for surface elemental analysis. A
remote controlled multi-sample holder has been designed and constructed to give
the analyzing system the ability to investigate more than one sample at same
operating conditions. The multi-sample holder has secured the gun cathode from
poisoning by residuals during sample change. First and second derivatives have
been experimentally obtained for Auger spectra by means of an audio frequency
modulation technique using a lock-in amplifier for the detection of Auger
spectra. Four samples have been investigated in order to check up the multi-
sample operation and to examine the existence of the copper, brass, nickel. and
iron in the chosen samples. A computer program has been used for the
calculation of the derivatives of the spectra obtained and for comparison with
that of the spectra obtained experimentally.
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