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An ultrasensitive spintronic strain‐gauge sensor and a spin‐MEMS microphone
Author(s) -
Fuji Yoshihiko,
Hara Michiko,
Higashi Yoshihiro,
Kaji Shiori,
Masunishi Kei,
Nagata Tomohiko,
Yuzawa Akiko,
Otsu Kenji,
Okamoto Kazuaki,
Baba Shotaro,
Ono Tomio,
Hori Akio,
Fukuzawa Hideaki
Publication year - 2019
Publication title -
electronics and communications in japan
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.131
H-Index - 13
eISSN - 1942-9541
pISSN - 1942-9533
DOI - 10.1002/ecj.12138
Subject(s) - spintronics , magnetostriction , materials science , tunnel magnetoresistance , microelectromechanical systems , microphone , spin valve , strain gauge , optoelectronics , giant magnetoresistance , magnetoresistance , electrical engineering , acoustics , condensed matter physics , nanotechnology , engineering , physics , layer (electronics) , ferromagnetism , magnetic field , composite material , quantum mechanics , loudspeaker
This review provides the spintronic strain‐gauge sensor (Spin‐SGS) based on a magnetic tunnel junction (MTJ) with a high gauge factor in excess of 5000, which was realized by adopting a novel amorphous Fe‐B‐based sensing layer with high magnetostriction and low coercivity in a high magnetoresistance Mg‐O barrier MTJ. This review also provides a demonstration of novel “Spintronic MEMS (Spin‐MEMS) microphone,” in which a series of Spin‐SGSs are integrated onto a bulk micromachined diaphragm. The Spin‐MEMS microphone exhibits a signal‐to‐noise ratio (SNR) of 57 dB(A) due to the high strain sensitivity of the Spin‐SGSs.