Presentation Information
[11a-E208-3]Manufacturable Top-BiSb SOT-MRAM Using a Conductive RuOx Interlayer
〇(D)Thuan Van Pham1, Ho Hoang Huy1, Pham Nam Hai1 (1.Department of Electrical and Electronic Engineering, Institute of Science Tokyo)
Keywords:
topological insulator,Spin orbit torque,BiSb
Spin-orbit torque magnetic random-access memory (SOT-MRAM) is a promising candidate for next-generation computing-in-memory hardware. BiSb topological insulators are attractive spin-current sources owing to their giant spin Hall angle and high electrical conductivity. However, practical implementation of BiSb-based SOT-MRAM remains challenging because most reported devices rely on epitaxial growth on non-industrial substrates, while the low melting point of BiSb (~285°C) limits compatibility with CMOS back-end-of-line processes. To address these issues, we propose a manufacturable top-BiSb SOT-MRAM structure employing a conductive RuOx interlayer. The top-BiSb architecture enables 400°C process compatibility, while the RuOx interlayer facilitates future integration with chemical mechanical polishing (CMP). The structure was fabricated on amorphous Si/SiO2 substrates and exhibited strong perpendicular magnetic anisotropy with Hk ≈ 10 kOe. Harmonic Hall measurements revealed a large effective spin Hall angle of 6.3, and current-induced switching was demonstrated with a threshold current density of ~3 MA cm−2 at a pulse width of 50 μs. These results demonstrate a practical pathway toward manufacturable BiSb SOT-MRAM.