Bruce Schneier, Surreptitiously Tampering with Computer ChipsАрхивная копия от 16 сентября 2013 на Wayback Machine // блог Schneier on Security, September 16, 2013: ""Stealthy Dopant-Level Hardware Trojans." Basically, you can tamper with a logic gate to be either stuck-on or stuck-off by changing the doping of one transistor. This sort of sabotage is undetectable by functional testing or optical inspection. And it can be done at mask generation -- very late in the design process"
Bruce Schneier, Surreptitiously Tampering with Computer ChipsАрхивная копия от 16 сентября 2013 на Wayback Machine // блог Schneier on Security, September 16, 2013: ""Stealthy Dopant-Level Hardware Trojans." Basically, you can tamper with a logic gate to be either stuck-on or stuck-off by changing the doping of one transistor. This sort of sabotage is undetectable by functional testing or optical inspection. And it can be done at mask generation -- very late in the design process"