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DARPA Looks To End the Scourge of Counterfeit Computer Gear
coondoggie writes "Few things can mess up a highly technical system and threaten lives like a counterfeit electronic component, yet the use of such bogus gear is said to be widespread. A new Defense Advanced Research Projects Agency (DARPA) program will target these phony products and develop a tool to 'verify, without disrupting or harming the system, the trustworthiness of a protected electronic component.'"
Used to be easy back when ICs had few layers and feature sizes that were resolvable with optical light microscopy.
I used to verify ICs for trustable computing back in the day, We would take aligned dieshots, develop them, project them through a red filter, project the master copy of the dieshot through a blue filter, overlay them and look for any large red or blue bits indicative that the metal was not the same. In light of recently published dopant sabotaged parts, it is obvious the technique we used back then was flawed, and not really applicable to modern chips which have many metal layers.
Destructive testing of representative samples can yield verification of all metal layers, but still doesn't cover the dopant sabotage technique (which we were not aware of at the time), of course you could try and slip things through by only sabotaging 5% or 10% of the parts.
I think a much more prevalent problem is counterfeit parts for commercial gain than sabotage, for example taking some cheap MOSFET with similar but worse characteristics and relabelling it as some expensive MOSFET. This happens frequently (found a batch of fake BJTs when I was building an amplifier, as the fake part had the wrong CBE pinout). Another common technique is taking low speed-grade DRAM, assembling it on DIMMs and programming SPD data that claims to be highspeed DRAM, often they don't even bother to change the labels on the device packages, as they are covered by a heatsink on most modern DIMMs.
The problem with out-of-grade counterfeiting is that the different grades are produced from identical masks, and can only be differentiated by very careful measurement of the device parameters. In some cases the counterfeits even meet every parameter, as they are produced by binning in the same way the the original manufacturer bins the parts prior to labelling. There are opamps which cost $40/each, and they are binned from the same line which makes parts costing $1/each, the manufacturer is even up front about this. Sometimes, the line produces more parts that would qualify for the $40/each part number than there is demand for the $40/each part, so the manufacturer just bins them as a lower price part. If the counterfeiter was upfront about it like the OEM, they would relabel them as their own part, with some guarantee about performance like the OEM provides, but then they wouldn't be a counterfeiter, but a legitimate re-binning service.
An example of legitimate rebinning is many of the high end audio equipment or lab equipment manufacturers. They often use commercial grade parts, have an internal test jig, and resell or dispose of parts that don't meet their higher-than-spec required parameters.