In recent years, a lot of the conversation around advancements in x-ray fluorescence (XRF) technology has related to the detector systems. XRF analyzers are offered with two major types of detector technologies…the more traditional proportional counter detectors and newer solid-state detectors. Unfortunately, even though proportional counter may be a great choice for some applications, it is often not discussed because the XRF sales company doesn’t offer it or are more focused on promoting the newer, more hyped, technology.
However, proportional counter detection systems still have a place and organizations looking to purchase an XRF should answer an important question before moving forward with any investment…“What detector system is best for our situation and testing goals?“
Any number of reasons can result in having an un-used XRF analyzer that ends up collecting dust or acting like a large paperweight - you may find yourself with an XRF that requires expensive repairs and you simply replaced the analyzer, don't have the testing requirements to have a system moving forward, or already have multiple systems and want to take one out of operation.
If your facility has an XRF that has been shelved, for any reason, then it may make more sense to properly dispose of the analyzer.
Our organization, Eastern Applied, works with a wide range of organizations on their x-ray fluorescence needs. We realize that budget is always a factor - regardless of whether we're working with a general metal finisher, academic laboratory, aerospace/military facility, or any other organizational type.
There are two budgetary considerations to make...both the short-term decision relating to the XRF analyzers price but also the long-term costs to maintain the system.
Two very common uses of x-ray fluorescence (XRF) spectrometers are measuring specific coatings used in the manufacturing of printed circuit boards; ENIG and ENEPIG coatings. The ENIG coating is immersion gold plated over electroless nickel on the bare board (Au/ENi/Cu) while the ENEPIG coating has a layer of electroless palladium in between the gold and nickel (Au/Pd/ENi/Cu) because it acts as a diffusion layer and limits nickel diffusion to the gold layer. These coatings have been available for some time and have become popular within the electronics industry because they provide a lead free option with a long shelf life, excellent solder-ability, and an ideal surface for wire bonding.
However, as you may already know, these coatings are relatively expensive options because of the gold, palladium, and nickel involved - so the question we hear is 'what is the best analytical tool for measuring ENIG and ENEPIG coatings?
Measuring coating thickness was one of the first applications of x-ray fluorescence spectrometry and is still one of the most common uses of the technology. So, the majority of analyzer certifications that Eastern Applied Research technicians provide are for coating thickness applications and those certifications actually reference the ASTM Standard B568. This standard is titled Standard Test Method for Measurement of Coating Thickness with X-Ray Spectrometry, and operators of ED-XRF systems (especially those new to the technology) may find it beneficial to take a few moments to read the standard.