Impact of Self-Heating on Reliability of a Spin-Torque-Transfer RAM Cell

This paper estimates the temperature distribution within a spin-torque-transfer RAM (STTRAM) cell due to self-heating using a thermal simulation based on the finite volume method. The analysis shows that, due to high switching current and small volume of the magnetic tunnel junction (MTJ), there can be significant rise in temperature in the MTJ as well as the silicon transistor. The impacts of the increased temperature on operational reliability metrics of the STTRAM cell, i.e., read disturb, write failure, and sensing accuracy, are evaluated. It is shown that, due to the self-heating effect, the operational reliability of an STTRAM cell depends on the read-write history of that cell.