Coating Thickness Software for Eagle µ-EDXRF Systems

6. Creation of a Multi-Layer Application (ex. Au/
Pd/ Ni/ Cu base)
The following procedures define how to analyze up to four (4) mono-element layers. In this example, the
“unknown” sample to be measured against the .c03 file will be 1.9um Au on 1.19um Pd on 2.57um Ni on
Cu base. Generally for “unknowns”, the users will have an idea of the target thicknesses. Having this
knowledge is useful in choosing standards. However, if the thicknesses are completely unknown, the user
will have to use the .c03 application from FunMaster (based on bulk intensities) to calculate standardless
values in ReCalib for the unknown sample, which can give an idea of which coating standards to choose.
The FunMaster routine will require saving the appropriate scatter spectrum, and the pure bulk intensities for
Au, Pd, Ni, and Cu. It will also be necessary to gather coating standards for .ADT files. For optimal results,
choose at least two coating standards for each layer; one thinner standard, and one thicker, so that the
layers are “bracketed.” For example, an appropriate set of coating standards for this scenario would be:
Available Standards:
• 0.47um, 4.08um Au (layer 3 – top Au)
• 0.61um, 3.02um Pd (layer 2 – middle Pd)
• 1.04um, 9.45um Ni (layer 1 – bottom Ni)
• Cu base
The FunMaster routine for multi-layers follows a similar procedure to that already described for single-layers.
However, after the FunMaster procedure, there will now be two separate stages/procedures to follow in the
multi-layer ReCalib routine. The first stage will require each layer element to be calibrated individually as
single-layer systems. That is, Au on Cu base, Pd on Cu base, and Ni on Cu base. Spectra and .ADT files
should be acquired for each of the individual single layers on a copper base.
For the second stage, the inter-layer effects associated with lower layer’s characteristic radiation passing
through the upper layers must be accounted for. To do so, the user must acquire spectra and .ADT files for
all layer combinations which could exhibit inter-layer effects. Thus, for this example, the user would use
the coating standards listed above to acquire .ADT files for all double layer (Au on Pd, Au on Ni, and
Pd on Ni).combinations. It is optional to create triple layer .ADT file(s) as well. Triple layer standard
measurements can be useful for checking the quality of the recalibration routine later. The order of the
layers cannot be altered, since that would no longer represent the inter-layer effects present in the sample.
Because there are two standards of each element, there are many permutations. For instance, examples of
appropriate layer systems for use as .ADT files for the second stage of this multi-layer example would be:
Double Layer .ADT Files
• Au on Pd on Cu base (3>2) - signifies correction for “the effect of the upper Au layer [3] on the
transmission of the Pd X-rays [ layer 2] to the detector.”
o 0.47um Au / 3.02um Pd
o 4.08um Au / 3.02um Pd
• Au on Ni on Cu base (3>1)
o 0.47um Au / 9.45um Ni
o 4.08um Au / 9.45um Ni
• Pd on Ni on Cu base (2>1)
4.1.2 Coating Thickness Results Panel in Vision32 44