TY - JOUR
T1 - Enhanced spin–orbit torque efficiency with low resistivity in perpendicularly magnetized heterostructures consisting of Si-alloyed β-W layers
AU - Kim, Taehyun
AU - Nguyen, Quynh Anh T.
AU - Won Kim, Gyu
AU - Hyeok Lee, Min
AU - In Yoon, Seok
AU - Rhim, Sonny H.
AU - Keun Kim, Young
N1 - Funding Information:
This study is supported by the National Research Foundation of Korea, funded by the Ministry of Science and ICT (2015M3D1A1070465 , 2020M3F3A2A01082591, 2019R1I1A3A01059880) and Samsung Electronics Co., Ltd. (IO201211-08104-01) . T. Kim acknowledges the support of the Global Ph.D. Fellowship Program through the National Research Foundation of Korea, funded by the Ministry of Education (2018H1A2A1062616).
Funding Information:
This study is supported by the National Research Foundation of Korea, funded by the Ministry of Science and ICT (2015M3D1A1070465, 2020M3F3A2A01082591, 2019R1I1A3A01059880) and Samsung Electronics Co. Ltd. (IO201211-08104-01). T. Kim acknowledges the support of the Global Ph.D. Fellowship Program through the National Research Foundation of Korea, funded by the Ministry of Education (2018H1A2A1062616).
Publisher Copyright:
© 2022 The Author(s)
PY - 2023/1/30
Y1 - 2023/1/30
N2 - Spin-orbit torque (SOT) based magnetization switching is of current technological interest to demonstrate its utilization in nonvolatile embedded memory and logic devices. These devices require perpendicular magnetic anisotropy (PMA) for high bit density, significant SOT efficiency to warrant low power consumption, and external field-free magnetization switching. Above all, materials associated with these devices must be semiconductor fabrication friendly. However, only a few materials and their heterostructures previously explored fulfill the requirements. Here, we propose a W–Si alloy, a widely used material in semiconductor devices, as the spin current-generating layer. First, we investigate the spin Hall conductivity of W–Si alloys by adding Si atoms to the β-W matrix using the first-principles calculations. Then, experimentally, we confirm that the heterostructure consisting of W-Si (4 at%)/CoFeB exhibits PMA, a high damping-like SOT efficiency (∼0.58), and low longitudinal resistivity (∼135 μΩ cm). Furthermore, we estimate ten times smaller write power consumption than the heterostructure based on the pristine β-W. The proposed W–Si/CoFeB heterostructures can withstand post-deposition heat treatment up to 500 °C.
AB - Spin-orbit torque (SOT) based magnetization switching is of current technological interest to demonstrate its utilization in nonvolatile embedded memory and logic devices. These devices require perpendicular magnetic anisotropy (PMA) for high bit density, significant SOT efficiency to warrant low power consumption, and external field-free magnetization switching. Above all, materials associated with these devices must be semiconductor fabrication friendly. However, only a few materials and their heterostructures previously explored fulfill the requirements. Here, we propose a W–Si alloy, a widely used material in semiconductor devices, as the spin current-generating layer. First, we investigate the spin Hall conductivity of W–Si alloys by adding Si atoms to the β-W matrix using the first-principles calculations. Then, experimentally, we confirm that the heterostructure consisting of W-Si (4 at%)/CoFeB exhibits PMA, a high damping-like SOT efficiency (∼0.58), and low longitudinal resistivity (∼135 μΩ cm). Furthermore, we estimate ten times smaller write power consumption than the heterostructure based on the pristine β-W. The proposed W–Si/CoFeB heterostructures can withstand post-deposition heat treatment up to 500 °C.
KW - First-principles calculation
KW - Longitudinal resistivity
KW - Microstructure
KW - Spin–orbit torque
KW - W-Si alloy
UR - http://www.scopus.com/inward/record.url?scp=85140486218&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2022.155352
DO - 10.1016/j.apsusc.2022.155352
M3 - Article
AN - SCOPUS:85140486218
SN - 0169-4332
VL - 609
JO - Applied Surface Science
JF - Applied Surface Science
M1 - 155352
ER -