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Back-scattering analysis and channel technology: When an
ion-beam bombards the nucleus of a sample, back-angle elastic
particles will result. Nuclei of different elements lead to
different amounts of energy carried by the particles being
reflected, thus the kinds of elements in the sample can be
distinguished. Moreover, bombarding ions would lose some
energy in the course of piercing into and reflecting out of the
sample. Therefore, difference appears in the particles reflected
from the identical element located at different depths.
means of this, the depth distribution of a certain element can
be detected. This method is suitable for the analysis of heavy
impurity elements in light host materials. If the bombarded
sample is a crystal and the ion-beam shoots in the direction
of the crystallographic axis, as if entering the "channel" in
the atomic arrangement, it will not come back. If the ion-beam
shoots in a direction deviating from the said crystallographic axis,
the ions would be catapulted back (i.e. back scattering). The
back-scattered particles change in line with the entering
direction. This phenomenon is called the channel back-scattering
technology. It is the most ideal method for detecting the radio-
active destruction of a sample and precise location of ion-atom.
This method finds its chief applications in solid physics,
material science, ion injection, thin-film growth, and surface
and depth analysis.
Accelerator mass-spectrographic analysis: the accelerator
is used as the mass-spectrometer, i.e. the sample to be tested
is put into the ionization source to be transformed into ions,
which undergo acceleration and electro-deflection, recorded
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The Translation Division of Tai Dao Publishing Ltc
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