The effect of γ-ray irradiation on the SOT magnetic films and Hall devices

Abstract

Magnetoresistive random access memories (MRAMs) have drawn the attention of radiation researchers due to their potential high radiation tolerance. In particular, spin-orbit torque MRAM (SOT-MRAM) has the best performance on endurance and access speed, which is considered to be one of the candidates to replace SRAM for space application. However, little attention has been given to the γ-ray irradiation effect on the SOT-MRAM device yet. Here, we report the Co-60 irradiation results for both SOT (spin-orbit torque) magnetic films and SOT-Hall devices with the same stacks. The properties of magnetic films are not affected by radiation even with an accumulated dose up to 300 krad (Si) while the magnetoelectronic properties of SOT-Hall devices exhibit a reversible change behavior during the radiation. We propose a non-equilibrium anomalous Hall effect model to understand the phenomenon. Achieved results and proposed analysis in this work can be used for the material and structure design of memory cell in radiation-hardened SOT-MRAM.