Saved in:
Bibliographic Details
Main Authors: Almeida, Trevor P., Palomino, Alvaro, Lequeux, Steven, Boureau, Victor, Fruchart, Olivier, Prejbeanu, Ioan Lucian, Dieny, Bernard, Cooper, David
Format: Preprint
Published: 2022
Subjects:
Online Access:https://arxiv.org/abs/2204.10220
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866916282813644800
author Almeida, Trevor P.
Palomino, Alvaro
Lequeux, Steven
Boureau, Victor
Fruchart, Olivier
Prejbeanu, Ioan Lucian
Dieny, Bernard
Cooper, David
author_facet Almeida, Trevor P.
Palomino, Alvaro
Lequeux, Steven
Boureau, Victor
Fruchart, Olivier
Prejbeanu, Ioan Lucian
Dieny, Bernard
Cooper, David
contents Perpendicular shape anisotropy (PSA) and double magnetic tunnel junctions (DMTJ) offer practical solutions to downscale spin-transfer-torque Magnetic Random-Access Memory (STT-MRAM) beyond 20 nm technology nodes, whilst retaining their thermal stability and reducing critical currents applied. However, as these modern devices become smaller and three-dimensionally (3D) complex, our understanding of their functional magnetic behavior is often indirect, relying on magnetoresistance measurements and micromagnetic modelling. In this paper, we review recent work that was performed on these structures using a range of advanced electron microscopy techniques, focusing on aspects specific to the 3D and nanoscale nature of such elements. We present the methodology for the systematic transfer of individual SST-MRAM nano-pillars from large-scale arrays to image their magnetic configurations directly using off-axis electron holography. We show that improved phase sensitivity through stacking of electron holograms can be used to image subtle variations in DMTJs and the thermal stability of < 20 nm PSA-STT-MRAM nano-pillars during in-situ heating. The experimental practicalities, benefits and limits of using electron holography for analysis of MRAM devices are discussed, unlocking practical pathways for direct imaging of the functional magnetic performance of these systems with high spatial resolution and sensitivity.
format Preprint
id arxiv_https___arxiv_org_abs_2204_10220
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Off-axis electron holography for the direct visualization of perpendicular shape anisotropy in nano-scale 3D magnetic random-access-memory devices
Almeida, Trevor P.
Palomino, Alvaro
Lequeux, Steven
Boureau, Victor
Fruchart, Olivier
Prejbeanu, Ioan Lucian
Dieny, Bernard
Cooper, David
Mesoscale and Nanoscale Physics
Perpendicular shape anisotropy (PSA) and double magnetic tunnel junctions (DMTJ) offer practical solutions to downscale spin-transfer-torque Magnetic Random-Access Memory (STT-MRAM) beyond 20 nm technology nodes, whilst retaining their thermal stability and reducing critical currents applied. However, as these modern devices become smaller and three-dimensionally (3D) complex, our understanding of their functional magnetic behavior is often indirect, relying on magnetoresistance measurements and micromagnetic modelling. In this paper, we review recent work that was performed on these structures using a range of advanced electron microscopy techniques, focusing on aspects specific to the 3D and nanoscale nature of such elements. We present the methodology for the systematic transfer of individual SST-MRAM nano-pillars from large-scale arrays to image their magnetic configurations directly using off-axis electron holography. We show that improved phase sensitivity through stacking of electron holograms can be used to image subtle variations in DMTJs and the thermal stability of < 20 nm PSA-STT-MRAM nano-pillars during in-situ heating. The experimental practicalities, benefits and limits of using electron holography for analysis of MRAM devices are discussed, unlocking practical pathways for direct imaging of the functional magnetic performance of these systems with high spatial resolution and sensitivity.
title Off-axis electron holography for the direct visualization of perpendicular shape anisotropy in nano-scale 3D magnetic random-access-memory devices
topic Mesoscale and Nanoscale Physics
url https://arxiv.org/abs/2204.10220