Platinum ($\mathrm{Pt}$) is one of the most promising spin-source materials for spin-orbit-torque (SOT) devices owing to its high spin Hall ratio and low resistivity. However, the high-temperature thermal processing required during fabrication of magnetic tunnel junctions causes $\mathrm{Pt}$ to agglomerate, degrading interface quality and thereby compromising SOT efficiency. In this work, we demonstrate that titanium ($\mathrm{Ti}$) doping simultaneously enhances the spin Hall ratio of $\mathrm{Pt}$ and preserves its performance after high-temperature annealing. Systematic spin-torque ferromagnetic resonance and spin Hall magnetoresistance measurements reveal that the optimally $\mathrm{Ti}$-doped alloy achieves 30% enhancement in spin Hall ratio while maintaining its performance after annealing even at 400 °C. In contrast, pure $\mathrm{Pt}$ experiences a 77% reduction in efficiency due to the loss of interfacial spin transparency. Structural characterization further indicates that $\mathrm{Ti}$ doping kinetically suppresses $\mathrm{Pt}$ atomic diffusion and thermodynamically stabilizes the interface, preventing agglomeration-induced roughening. These findings establish $\mathrm{Pt}\mathrm{Ti}$ alloys as thermally stable spin-source materials for energy-efficient SOT-magnetoresistive random-access memory applications.

Close

PrevNext

View figure in article

• Doping effects
• Spin-orbit torque
• Devices for digital logic, storage & processing
• Magnetic multilayers
• Magnetic thin films
• Transition metals
• Annealing
• Ferromagnetic resonance