MRAM: from STT to SOT, for security and memory

Spin Transfer Torque Magnetic Random Access Memory (STT-MRAM) is one of the leading candidates for embedded memory convergence in advanced technology nodes. It is particularly adapted to low-power applications, requiring a decent level of performance. However, it also have interests for secured applications. The PRESENT cipher is a lightweight cryptographic algorithm targeting ultra-low power applications such as the Internet of Things or RFID. This paper aims to combine this low power cryptographic algorithm with the STT-MRAM which main feature is its low consumption. This new generation of ciphers is very interesting for normally-off applications. Actually, for these specific applications hybrid CMOS/STT-MRAM ciphers consume less power than pure CMOS cryptographic algorithms.Although the performance of STT-MRAM is much better than standard non-volatile technologies like flash, it suffers from limitations for high-speed applications. A new MRAM technology based on Spin-Orbit Torque (SOT) was recently discovered and offers better performance in terms of speed and endurance, at the expense of a slightly degraded density. In this paper, we also propose a comparative study of several architectures of SOT-MRAM memories for evaluating the possible advantages of this NV technology for high-speed applications.