Decapsulation and Die Verification
Although decapping can confirm if you have authentic internal die, it is dependent on how much information is available on the die for giving clear determinations. If a component has been re-graded, it is possible only the series of the callout is listed on the die. Decapping is used as just one procedure in an arsenal of avoidance techniques and should not be used as a sole determination.
XRF (X-Ray Fluorescence Analysis)
XRF is one of the most effective tools you can have in your anti-counterfeit arsenal because it tells you the elemental composition of the device. Last year, we received in suspect tantalum capacitors and were able to confirm the elemental makeup of the components were vastly different from a known good lot. Although the capacitors passed electrical screening, it was XRF that produced a clear red flag for rejection.
I do not recommend using electrical screening as a sole determining factor. Again, if a part has been re-graded, they will most likely pass screening and can make it into the field where a latent failure can occur. One of the major problems with re-graded components is a commercial item is being used in a rugged environment, such as high temperature or extreme vibrations, even though it has not been built or tested to withstand such variables. However, parametric electrical is a great tool in evaluating if any ESD shorts are occurring in the device. Sufficient labs will test the input/output ratings against the temperature grades and speed to confirm all are within OEM spec documentation as well.
Scanning Acoustic Microscope (C-SAM)
By using high-frequency sound, C-SAM is able to penetrate internal defects not detected by traditional X-ray. Component’s exposed to moisture and temperature fluctuations over time may result in delamination, causing cracks or stressing of the internal die. Although no signs of failure may be occurring at time of electrical test, this is a great indicator of possible potential failures in the field if signs of delamination or showing.
Always remember, counterfeit avoidance and mitigation is about having a robust program in place that collects data from many key areas, not relying on just one or two procedures. Start with the most basic and cost effective processes and work your way up to the more in depth items. Having a full arsenal of avoidance practices at your fingertips can provide you clear determinations that can keep a supply line free of substandard and counterfeit components.
Christopher Torrioni is President and co-founder of Sensible Micro Corporation, a professional stocking distributor and sourcing partner to hundreds of global OEM and EMS manufacturing companies. He obtained his Bachelor's Degree from the University of Central Florida and brings 11 years of industry knowledge and experience in electronic component supply, market news, procurement pitfalls and quality assurance standards. Torrioni is also a corporate sponsor to the SMTA Tampa Bay Chapter, as well as the Tampa Chamber of Commerce and Tampa Bay Technology Forum.