The LeadTracer Handheld XRF (Figure 5-1) by RMD Instruments Corporation is the optimal, first line screening tool for the Restriction of Hazardous Substances (RoHS) compliance. Light weight, portable, fast, and accurate, this XRF can be used for incoming inspection, in process testing, and final assembly verification.
X-ray fluorescence (XRF) analysis is a well established, non-destructive analytical technique for elemental analysis that has been used for over half a century. A vital part of the electronic assembly process, its ability to clearly identify the presence or absence of elements in a component or assembly is important in detecting counterfeit components or validating authentic ones. When a primary x-ray from a radioactive source strikes a sample, electrons are ejected from the inner shells, creating vacancies. To fill the vacancies and return to a stable state, outer shell electrons drop to the inner shell and give off a characteristic x-ray whose energy is the difference between the two shells. This energy is unique to each element and can be used to non-destructively measure the elemental composition of a sample. This process of emitting characteristic x-rays is called “X-ray Fluorescence,” or XRF. By using a radiation source instead of an x-ray tube, the LeadTracer XRF system produces the higher energy K-shell characteristic x-rays that are not masked by some common elements which could cause a false negative. The handheld unit can provide the spectrometric data through components and packaging without needing to disturb the actual component or the packaging materials.
The need for screening incoming materials and monitoring the assembly process against intrusion of non-RoHS compliant materials is essential and must be done in an efficient, non-destructive yet accurate way. In addition to the critical task of measuring and confirming the presence or absence of trace materials in a specimen (such as certain RoHS restricted elements: Cr, Br, Pb, Hg, and Cd), XRF analysis can help prevent counterfeit electronic components from entering the supply chain.
Components manufactured under false trade names are creating another type of challenge for the electronics manufacturing industry. These components are often made from the same external materials as real parts and pass electronic functionality tests. However, material compositions of this group may be substandard, thus compromising capabilities in extreme temperature and pressures. In the majority of cases, the substandard components do not contain expensive elements such as gold (Au), bismuth (Bi), tantalum (Ta), and silver (Ag). Instead, the more expensive elements are often replaced by less costly materials such as lead (Pb) or palladium (Pd).
Whether the information sought from x-ray fluorescence is to qualify materials for RoHS or another critical analysis, the data provided by XRF is a pre-requisite for such conclusions. The portable, handheld XRF analyzer by RMD Instruments is a very good choice when considering a tool to provide quick and easy elemental analysis.
For more information on the LeadTracer handheld XRF unit by RMD Instruments or to schedule a demonstration, please contact the EAB Coordinator, Ken Friedman, at 610.362.1200, extension 279 or via email at kfriedman@aciusa.org.
