As electronics manufacturers and distributors face an ongoing and significant threat from counterfeit components, they must protect themselves appropriately. In this article, Andy Bonner of inspection and test specialist Cupio (part of the IPP Group), looks at the counterfeit types that can be encountered, and then discusses how to combat their influx.
Forms of counterfeit
The Semiconductor Industry Association (SIA) classifies counterfeit parts into the following types:
1. The part has incorrect or false markings and/or documentation
2. It is an unauthorised copy
3. It is not produced by the original component manufacturer (OCM) or is produced by unauthorised contractors
4. It is an off-specification, defective, or used OCM product sold as “new” or working
5. It does not conform to OCM design, model, and/or performance standards
From the manufacturing user’s perspective, counterfeit components of any, some, or all of the above types could be hidden within incoming goods deliveries. However, they manifest themselves in different ways.
Type 1 parts would be clearly identifiable as counterfeits, if we could see inside them, as they won’t have the internal structure implied by their label or documentation. X-ray inspection can supply the solution here.
Types 2 and 3 may not be visually distinguishable – even internally, using x-rays – from good components. However, being of unknown and probably inferior quality, they are liable to field failure, where they’ll create the greatest harm in terms of safety risk, financial cost and reputation damage. Electrical testing becomes necessary, to reveal shortcomings in their performance.
Similarly, Type 4 counterfeits will appear visually like good components. However, as we will see, some can be identified using acoustic micro imaging.
Type 5 counterfeits could respond variously to investigation like types 1 – 4, depending on how they have been falsified.
Accordingly, a truly comprehensive counterfeit-trapping strategy will include x-ray inspection, electrical testing and acoustic micro-imaging working in complement to one another.
X-ray inspection
High-resolution x-ray inspection allows users to instantly see inside incoming components without destroying them, and compare the images with those from known good parts. Components that appear externally identical often have internal differences if they are from different manufacturers or production lines, as Fig.1 shows.
Fig.1: X-ray images of $10 transimpedance diode – Real (L) and Counterfeit (R) (Courtesy Nordson Dage)
Often, a fake component may be more blatantly falsified. Fig.2’s counterfeit diode, for example, is a wrong part that has been further modified. In any case, anomalies in lead wires, die sizes and positions, and truncated pins, can all be identified.
Fig.2: Ultra-fast diode – Real (L) and Counterfeit (R) (Courtesy Nordson Dage)
Overall, x-ray inspection, using a high-resolution x-ray microscope like Nordson Dage’s Explorer one can facilitate rapid detection of counterfeit components. The machine itself is simple to use, and components can be inspected while still sealed within their shipping materials; making them logistically and commercially easier to return if necessary.
Electrical testing
Electrical testing is used to check a component’s performance against its published specification. This is done by analysing the component’s pins’ electrical characteristics under dynamic stimulus. The pin response relates directly to the component’s nature, internal structure and manufacturing processes. This strongly indicates whether or not the component’s bond wire and die configuration conform to the expected specification.
Fig.3: Component electrical characteristic traces (Courtesy ABI Electronics)
Acoustic micro-imaging
Acoustic imaging complements X-ray techniques by providing information on different aspects of component integrity.
Nordson SONOSCAN acoustic imaging technology, for example, transmits high-frequency sound waves into the sample immersed in deionised water. Reflected sound waves help to accurately identify internal dimensions, cracks, voids, delaminations and interface quality issues characteristic of re-used components. A layer-by-layer analysis of material properties as well as material consistency and thickness helps separate the real components from the imposters.
Fig.4: Acoustic micro-image of two externally near-identical components. The lower component is counterfeit.
Accessing counterfeit detection technology
As explained, a comprehensive counterfeit detection lineup would comprise three machines – x-ray microscope, acoustic micro-imager and electrical tester. With an x-ray machine, for example, costing in the order of £100,000, this would represent a significant investment. In many cases, this can be amortised, as the equipment would also fulfil roles within production and quality control areas. Larger companies may also be able to justify the expenditure by considering the volume of components processed, and the potential cost of a counterfeit contamination.
Alternatively, companies like Cupio offer inspection and testing as a service. With no ties to any component manufacturer or distributor, they can provide impartial third-party advice and results. And their costs, although dependent on the nature and amount of testing, would be a fraction of any capital machine expenditure.
Such a service can be made extremely cost-effective simply through customisation to each client’s individual circumstances. A typical approach would start with x-ray inspection, as it’s the simplest and quickest to perform. Any samples appearing as visually good, while still in doubt, could then be subjected to detailed electrical testing.
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