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Abstract Ferrimagnetic iron garnets enable magnetic and magneto‐optical functionality in silicon photonics and electronics. However, garnets require high‐temperature processing for crystallization which can degrade other devices on the wafer. Here bismuth‐substituted yttrium and terbium iron garnet (Bi‐YIG and Bi‐TbIG) films are demonstrated with good magneto‐optical performance and perpendicular magnetic anisotropy (PMA) crystallized by a microheater built on a Si chip or by rapid thermal annealing. The Bi‐TbIG film crystallizes on Si at 873 K without a seed layer and exhibits good magneto‐optical properties with Faraday rotation (FR) of −1700 deg cm−1. The Bi‐YIG film also crystallizes on Si and fused SiO2at 873 K without a seed layer. Rapidly cooled films exhibit PMA due to the tensile stress caused by the thermal expansion mismatch with the substrates, increasing the magnetoelastic anisotropy by 4 kJ m−3versus slow‐cooled films. Annealing in the air for 15 s using the microheater yields fully crystallized Bi‐TbIG on the Si chip.
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Sputtered L 1 0 ‐FePd and its Synthetic Antiferromagnet on Si/SiO 2 Wafers for Scalable Spintronics
Abstract As a promising alternative to the mainstream CoFeB/MgO system with interfacial perpendicular magnetic anisotropy (PMA),L10‐FePd and its synthetic antiferromagnet (SAF) structure with large crystalline PMA can support spintronic devices with sufficient thermal stability at sub‐5 nm sizes. However, the compatibility requirement of preparingL10‐FePd thin films on Si/SiO2wafers is still unmet. In this paper, high‐qualityL10‐FePd and its SAF on Si/SiO2wafers are prepared by coating the amorphous SiO2surface with an MgO(001) seed layer. The preparedL10‐FePd single layer and SAF stack are highly (001)‐textured, showing strong PMA, low damping, and sizeable interlayer exchange coupling, respectively. Systematic characterizations, including advanced X‐ray diffraction measurement and atomic resolution‐scanning transmission electron microscopy, are conducted to explain the outstanding performance ofL10‐FePd layers. A fully‐epitaxial growth that starts from MgO seed layer, induces the (001) texture ofL10‐FePd, and extends through the SAF spacer is observed. This study makes the vision of scalable spintronics more practical.
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- Award ID(s):
- 2226579
- PAR ID:
- 10410792
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 33
- Issue:
- 18
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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