PoP DRAM: A new EMFI approach based on EM-induced glitches on SoC

Modern mobile devices such as smartphones make use of complex Systems-on-Chip (SoC) that often come with a DRAM chip stacked above the SoC. This packaging method that was designed to increase space efficiency is called a Package-on-Package (PoP). PoP has also an incidental impact on local Fault Injection methods such as Electromagnetic Fault Injection (EMFI). This paper shows that conventional EMFI may not always be the most effective approach for inducing faults into a SoC implemented in a PoP. We provide and compare methodologies to successfully induce faults within this kind of target. A PoP DRAM can be removed while keeping the SoC operationnal during the first boot stages. We applied this method and used conventional EMFI on a SoC without DRAM. We also present a new way to induce voltage glitches on the target power supply rail by using EM pulses. Conventional voltage glitches are also performed in order to compare the faults obtained. It appeared that faults injected by EM-induced glitches are closer to faults obtained with conventional EMFI than faults induced by conventional voltage glitches.