A Comprehensive Study of Temperature and Its Effects in SOT-MRAM Devices

Area of Science:

• Condensed Matter Physics
• Materials Science
• Electrical Engineering

Background:

• Spin-orbit torque (SOT) is a key mechanism for efficient magnetization switching in next-generation memory devices like MRAM.
• Understanding temperature effects is crucial for reliable MRAM operation, as device performance can be temperature-dependent.

Purpose of the Study:

• To investigate the influence of temperature dynamics on the switching behavior of SOT-MRAM.
• To explore how temperature scaling affects magnetization parameters and switching characteristics.

Main Methods:

• A fully three-dimensional numerical model was developed, coupling magnetization, charge, spin, and temperature dynamics.
• Spin currents were incorporated via the spin Hall effect, and magnetization parameters were scaled with temperature.
• Numerical experiments were conducted to analyze temperature dynamics and switching phenomena.

Main Results:

• Temperature dynamics exhibit multiple time scales, including a rapid initial rise followed by slower increases.
• The gradual temperature rise leads to an incubation time for switching, which is absent in constant temperature simulations.
• Increased operating temperature significantly reduces the critical SOT switching voltage for field-free SOT-MRAM.
• External-field-assisted switching shows a parabolic decrease in critical SOT voltage with applied MTJ voltage.

Conclusions:

• Temperature dynamics play a critical role in SOT-MRAM switching, introducing incubation times and reducing switching energy.
• The developed model accurately captures experimentally observed phenomena, highlighting the importance of considering thermal effects.
• These findings provide valuable insights for optimizing SOT-MRAM device design and performance.