Direct Magnetic Imaging of Ferromagnetic Domain Structures   by Room Temperature Scanning Hall Probe Microscopy Using a Bismuth Micro-Hall Probe

Sandhu, Adarsh; Masuda, Hiroshi; Oral, Ahmet; Bending, Simon

doi:10.1143/jjap.40.l524

Cited by 24 publications

(16 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…13,14) Figure 2 shows a $1 mm size 2DEG micro-Hall probe with a Hall coefficient of R H $ 0:16 /Gauss and a series resistance of R s ¼ 5 { 6 k at 77 K. At that temperature, GaAs/AlGaAs 2DEG micro-Hall sensors exhibit a noise level of $1 mG/ ffiffiffiffiffiffi Hz p .…”

Section: Hall Probe Fabricationmentioning

confidence: 99%

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi₂Sr₂CaCu₂O_8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy

Dede

Oral

Yamamoto

et al. 2006

jjap

Self Cite

View full text Add to dashboard Cite

Vortices in superconductors play an important role in operating limits and applications of the superconductors. Scanning Hall probe microscopes have proven themselves to be quantitative and non-invasive tools for investigating magnetic samples down to 50 nm scale. Penetration of vortices in high quality single crystal Bi 2 Sr 2 CaCu 2 O 8þ superconductor has been studied in real-time with single vortex resolution at 77 K using a low temperature scanning Hall probe microscope (LT-SHPM). Vortices have been observed to be annihilated by the antivortices in small M-H loops.

show abstract

Section: Hall Probe Fabricationmentioning

confidence: 99%

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi₂Sr₂CaCu₂O_8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy

Dede

Oral

Yamamoto

et al. 2006

jjap

Self Cite

View full text Add to dashboard Cite

show abstract

“…1(b)]. Bi is a semimetal with a carrier concentration fifth-order magnitude smaller than metals, low resistivity, and negligible surface charge depletion effects, the usual limiting factor to the miniaturization of semiconductor devices [16]. Hexamethyldisulazane (HMDS) adhesion promoter is used in an oven at 150 C to enhance the bonding of the photoresist to the polysilicon surface.…”

Section: A Hall Sensors and Electrodesmentioning

confidence: 99%

Polymer-Based Cantilevers With Integrated Electrodes

Mouaziz

Boero

Popović

et al. 2006

J. Microelectromech. Syst.

View full text Add to dashboard Cite

Abstract-An innovative release method of polymer cantilevers with embedded integrated metal electrodes is presented. The fabrication is based on the lithographic patterning of the electrode layout on a wafer surface, covered by two layers of SU-8 polymer: a 10-m-thick photo-structured layer for the cantilever, and a 200-m-thick layer for the chip body. The releasing method is based on dry etching of a 2-m-thick sacrificial polysilicon layer. Devices with complex electrode layout embedded in free-standing 500-m-long and 100-m-wide SU-8 cantilever were fabricated and tested. We have optimized major fabrication steps such as the optimization of the SU-8 chip geometry for reduced residual stress and for enhanced underetching, and by defining multiple metal layers [titanium (Ti), aluminum (Al), bismuth (Bi)] for improved adhesion between metallic electrodes and polymer. The process was validated for a miniature 2 2 m 2 Hall-sensor integrated at the apex of a polymer microcantilever for scanning magnetic field sensing. The cantilever has a spring constant of =1 N/m and a resonance frequency of =17 kHz. Galvanometric characterization of the Hall sensor showed an input/output resistance of 200 , a device sensitivity of 0.05 V/AT and a minimum detectable magnetic flux density of 9 T/Hz 1 2 at frequencies above 1 kHz at room temperature. Quantitative magnetic field measurements of a microcoil were performed. The generic method allows for a stable integration of electrodes into polymers MEMS and it can readily be used for other types of microsensors where conducting metal electrodes are integrated in cantilevers for advanced scanning probe sensing applications.[1573]Index Terms-Dry etch, Hall sensor, integrated electrodes, polysilicon sacrificial layer, stress-reducing geometries, SU-8 cantilever, thin film metal deposition and lift off.

show abstract

“…Thus selection of the material for fabricating the HP is very important in order to obtain high spatial resolution and high magnetic sensitivity. We have previously reported on the use of $1 lm 2 GaAs/AlGaAs 2DEG heterostructure (GaAs-2DEG) Hall-effect sensors as HPs for room temperature scanning Hall probe microscope (RT-SHPM) [3][4][5][6][7]. In spite of their excellent room temperature magnetic sensitivity, the GaAs-2DEG HPs are impractical for high spatial resolution RT-SHPM measurements because their performance is severely degraded for dimensions below $1.0 lm 2 due to surface depletion effects that limit the maximum drive current (I max ) and consequently the magnetic sensitivity.…”

Section: Introductionmentioning

confidence: 99%

Nano and micro Hall-effect sensors for room-temperature scanning hall probe microscopy

Sandhu¹

2004

Microelectronic Engineering

View full text Add to dashboard Cite

GaAs/AlGaAs two-dimensional electron gas (GaAs-2DEG) Hall probes are impractical for sub-micron roomtemperature scanning Hall microscopy (RT-SHPM), due to surface depletion effects that limit the Hall driving current and magnetic sensitivity (B min ). Nano and micro Hall-effect sensors were fabricated using Bi and InSb thin films and shown to be practical alternatives to GaAs-2DEG probes for high resolution RT-SHPM. The GaAs-2DEG and InSb probes were fabricated using photolithography and the Bi probes by optical and focused ion beam lithography. Surface depletion effects limited the minimum feature size of GaAs-2DEG probes to $1.5 lm 2 with a maximum drive current I max of $3 lA and B min $ 0:2 G/ ffiffiffiffiffiffi ffi Hz p . The B min of 1.5 lm 2 InSb Hall probes was 6 Â 10 À3 G/ ffiffiffiffiffiffi ffi Hz p at I max of 100 lA. Further, 200 nm Â 200 nm Bi probes yielded good RT-SHPM images of garnet films, with I max and sensitivity of 40 lA and $0.80 G/ ffiffiffiffiffiffi ffi Hz p , respectively.

show abstract

Direct Magnetic Imaging of Ferromagnetic Domain Structures by Room Temperature Scanning Hall Probe Microscopy Using a Bismuth Micro-Hall Probe

Cited by 24 publications

References 8 publications

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi₂Sr₂CaCu₂O_8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi₂Sr₂CaCu₂O_8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy

Polymer-Based Cantilevers With Integrated Electrodes

Nano and micro Hall-effect sensors for room-temperature scanning hall probe microscopy

Contact Info

Product

Resources

About

Direct Magnetic Imaging of Ferromagnetic Domain Structures by Room Temperature Scanning Hall Probe Microscopy Using a Bismuth Micro-Hall Probe

Cited by 24 publications

References 8 publications

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi2Sr2CaCu2O8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi2Sr2CaCu2O8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy

Polymer-Based Cantilevers With Integrated Electrodes

Nano and micro Hall-effect sensors for room-temperature scanning hall probe microscopy

Contact Info

Product

Resources

About

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi₂Sr₂CaCu₂O_8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy

Real-Time Imaging of Vortex–Antivortex Annihilation in Bi₂Sr₂CaCu₂O_8+δ Single Crystals by Low Temperature Scanning Hall Probe Microscopy