Monitoring the measurement devices
Product Administration
FISCHERSCOPE
®
X-RAY
63
excitation. Any combination of substrates not allowed in this context
will be rejected. In any cases where a component of a layer is
secondarily excited by a component of the base material
fluorescence the definition "composition unknown" must not be
used but the substrate has to be defined explicitly. Equally this is
recommended if same element is content both of one ore more
layers and of the substrate.
Another specialty is the ratio method. This evaluation method
utilizes relative count rates or the method of "internal normalization"
(count rates of one or more layers relative to the count rate of the
substrate).
An example of this method comprises the measurement of samples
with an area which is smaller than the measuring spot size (wires,
lead frames, etc.). This method uses the fluorescence radiation of
the substrate, so it has to be known exactly, i.e. which elements the
substrate contains quantitatively. From this we conclude:
Base material "composition unknown" must not be used with
secondary excitation,
strong peak overlap,
multiple content of same element,
ratio method.
On the other hand, "composition unknown" is prerequisite if the
substrate is a source of substantial scattering, like with plastics,
fluids, light metals etc. Scattered radiation is not handled by the
fundamental parameter method and cannot be evaluated
theoretically by WinFTM. Therefore it has to be evaluated
empirically. The user must define base material as "unknown" in
applications where scattering is important and has to measure the
real substrate during normalization and calibration.
8.15 Monitoring the measurement devices
Why is it necessary to check the instrument?
Short answer: To ensure at all times that an instrument without or
at most with very small measurement deviations is available.
Technical background:
With the X-ray fluorescence method, as with any non-destructive
measurement method, the measurement data are calculated
indirectly.
Summary of Contents for FISCHERSCOPE X-RAY XDLM 231
Page 8: ...6 FISCHERSCOPE X RAY Table of Contents...
Page 14: ...12 FISCHERSCOPE X RAY Safety Information...
Page 30: ...28 FISCHERSCOPE X RAY Set up...
Page 36: ...34 FISCHERSCOPE X RAY WinFTM File Structure...
Page 52: ...50 FISCHERSCOPE X RAY User Interface of the WinFTM Software...
Page 134: ...132 FISCHERSCOPE X RAY Def MA...
Page 146: ...144 FISCHERSCOPE X RAY Programming Coordinates for Automatic Measurements XDLM 237...
Page 186: ...184 FISCHERSCOPE X RAY Pattern Recognition XDLM 237...
Page 192: ...190 FISCHERSCOPE X RAY Cleaning and Maintenance...
Page 202: ...200 FISCHERSCOPE X RAY Addendum...
Page 228: ...226 FISCHERSCOPE X RAY WinFTM SUPER For the Experienced X RAY User...
Page 229: ...FISCHERSCOPE X RAY 227...
Page 232: ......