Magnetic tunnel junction based out-of-plane field sensor with perpendicular magnetic anisotropy in reference layer

Lee, Y. C.; Chao, C. T.; Li, L. C.; Suen, Y. W.; Horng, Lance; Wu, Teresa; Chang, Ching‐Ray; Wu, Jian-Da

doi:10.1063/1.4914121

Cited by 21 publications

(10 citation statements)

References 13 publications

(11 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The synthetic anti-ferromagnet (SAF) was also applied to enhance the PMA and reduce the stray field from RL acting on SL. After the deposition, the annealing process at 350 °C for 1 h was applied to build the interfacial anisotropy between MgO and CoFeB, which caused the bottom CoFeB to become PMA and reduced the in-plane anisotropy of the top CoFeB [ 17 , 18 ]. The MR ratio was also enhanced due to the crystallization of CoFeB and MgO during the annealing process [ 19 ].…”

Section: Methodsmentioning

confidence: 99%

Alignment-Free Sensing Module for Absolute and Incremental Lines in Linear Positioning System Based on Tunneling-Magnetoresistance Sensors

Lee

Yen

Lai

2021

Sensors

View full text Add to dashboard Cite

An alignment-free sensing module for the positioning system based on tunneling magnetoresistive (TMR) sensors with an absolute-incremental-integrated scale is demonstrated. The sensors of the proposed system for both lines consist of identical layer stacks; therefore, all sensors can be fabricated in identical processes from thin film deposition to device patterning on a single substrate. Consequently, the relative position of the sensors can be predefined at the lithography stage and the alignment error between sensors caused by the manual installation is completely eliminated. Different from the existing sensing scheme for incremental lines, we proposed to utilize the magnetic tunnel junctions with a perpendicular anisotropy reference layer and an in-plane anisotropy sensing layer. The sensors are placed parallel to the scale plane with magnetization of the sensing layer in the plane, which show the capability of polarity detection for the absolute line and reveal sinusoidal output signal for the incremental line. Furthermore, due to the large signal of TMR, the working distance can be further improved compared with conventional sensors. In addition, the cost of the positioning system is expected to be lowered, since all the sensors are fabricated in the same process without extra installation. Our design may pave a new avenue for the positioning system based on a magnetic detection scheme.

show abstract

Section: Methodsmentioning

confidence: 99%

Alignment-Free Sensing Module for Absolute and Incremental Lines in Linear Positioning System Based on Tunneling-Magnetoresistance Sensors

Lee

Yen

Lai

2021

Sensors

View full text Add to dashboard Cite

show abstract

“…The pseudo resistor of RC feedback network should hold as possible as high resistance so that the area of capacitor can be decreased. The resistance of MTJ is inversely proportional to the area [30]. Therefore, the MTJ can show high resistance while occupy small area.…”

Section: The Analysis Of Noisementioning

confidence: 99%

Novel Low Noise Amplifier for Neural Signals Based on STT-MTJ Spintronic Device

Pan

Karymy

et al. 2019

IEEE Access

View full text Add to dashboard Cite

Low noise amplifier is generally adopted in brain-machine interface (BMI) for the purpose of the extraction of action potentials of neural signals from the Local Field Potentials (LFPs). However, the frequency ranges of these signals are very near to those of the LFPs and other existing noises. So the matter brings us difficulties in order to designing of the amplifier. The purpose of this paper is concentrated on designing of a low noise amplifier specific for the neural signals. Based on the STT-MTJ spintronic devices, the amplifier selectively amplifies the high amplitude peaks, while suppresses the low amplitude peaks. In this way, the novel amplifier can be used to amplify the useful neural signals not only based on the frequency but also on the amplitude. At the same time, the noise signals are suppressed by the amplifier. The low cut-off frequency of the amplifier is adjusted to be 1.24 Hz. The gain of the amplifier is adjusted to be 39.8 dB from 1.24 Hz to 9.1 KHz. In this bandwidth, the input-referred noise is 33.7 nV/ √Hz and the RMS noise is 1.9 µVrms. This novel amplifier can have potential application in the field of neural signal recording and other related fields.

show abstract

“…The perpendicular easy axis of sensing layer is generated from CoFe layer pinned with CoFe/Pt multilayer, while its formation is completely natural without additional thermal processing. Another kind of perpendicular magnetic field sensor based on CoFeB/MgO interface has been proposed by Lee et al [66] in 2015. Because of the opposite magnetization direction situation as illustrated in Figure 8b, perpendicular magnetic field can be characterized with linear magnetoresistance response without rotating the position of sensor.…”

Section: Perpendicular Magnetic Anisotropy For Magnetic Field Sensormentioning

confidence: 99%

Tunnel Junction with Perpendicular Magnetic Anisotropy: Status and Challenges

et al. 2015

View full text Add to dashboard Cite

Magnetic tunnel junction (MTJ), which arises from emerging spintronics, has the potential to become the basic component of novel memory, logic circuits, and other applications. Particularly since the first demonstration of current induced magnetization switching in MTJ, spin transfer torque magnetic random access memory (STT-MRAM) has sparked a huge interest thanks to its non-volatility, fast access speed, and infinite endurance. However, along with the advanced nodes scaling, MTJ with in-plane magnetic anisotropy suffers from modest thermal stability, high power consumption, and manufactural challenges. To address these concerns, focus of research has converted to the preferable perpendicular magnetic anisotropy (PMA) based MTJ, whereas a number of conditions still have to be met before its practical application. This paper overviews the principles of PMA and STT, where relevant issues are preliminarily discussed. Centering on the interfacial PMA in CoFeB/MgO system, we present the fundamentals and latest progress in the engineering, material, and structural points of view. The last part illustrates potential investigations and applications with regard to MTJ with interfacial PMA.

show abstract

Magnetic tunnel junction based out-of-plane field sensor with perpendicular magnetic anisotropy in reference layer

Cited by 21 publications

References 13 publications

Alignment-Free Sensing Module for Absolute and Incremental Lines in Linear Positioning System Based on Tunneling-Magnetoresistance Sensors

Alignment-Free Sensing Module for Absolute and Incremental Lines in Linear Positioning System Based on Tunneling-Magnetoresistance Sensors

Novel Low Noise Amplifier for Neural Signals Based on STT-MTJ Spintronic Device

Tunnel Junction with Perpendicular Magnetic Anisotropy: Status and Challenges

Contact Info

Product

Resources

About