Diamagnetic Levitation of Beads and Cells Above Permanent Magnets

Chetouani, Hichem; Haguet, Vincent; Jeandey, C.; Pigot, Christian; Walther, Arnaud; Dempsey, Nora; Chatelain, François; Delinchant, Benoît; Reyne, Gilbert

doi:10.1109/sensor.2007.4300230

Cited by 13 publications

(9 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The relevance of this result is that following a simple fabrication procedure (deposition + annealing of the magnetic layer), the trivial application of a uniaxial magnetic field can be used to produce a micron-scaled multi-polar field pattern. These micropatterned films have been used to levitate diamagnetic beads, 13 and have potential applications in lab-on-chip experiments.…”

Section: -Magnetic Properties Following Deposition Onto Patterned Smentioning

confidence: 99%

Micro-patterning of NdFeB and SmCo magnet films for integration into micro-electro-mechanical-systems

Walther

Marcoux

Desloges

et al. 2009

Journal of Magnetism and Magnetic Materials

Self Cite

View full text Add to dashboard Cite

The integration of high performance RE-TM (NdFeB and SmCo) hard magnetic films into Micro-Electro-Mechanical-Systems (MEMS) requires their patterning at the micron scale.In this paper we report on the applicability of standard micro-fabrication steps (film deposition onto topographically patterned substrates, wet etching and planarization) to the patterning of 5 µm thick RE-TM films. While NdFeB comprehensively fills micron scaled trenches in patterned substrates, SmCo deposits are characterized by poor filling of the trench corners, which poses a problem for further processing by planarization. The magnetic hysteresis loops of both the NdFeB and SmCo patterned films are comparable to those of non-patterned films prepared under the same deposition/annealing conditions. A micron-scaled multipole magnetic field pattern is directly produced by the unidirectional magnetization of the patterned films. NdFeB and SmCo show similar behavior when wet etched in an amorphous state: etch rates of approximately 1.25µm/minute and vertical side walls which may be attributed to a large lateral over-etch of typically 20 µm. ChemicalMechanical Planarization (CMP) produced material removal rates of 0.5-3µm/min for amorphous NdFeB. Ar ion etching of such films followed by the deposition of a Ta layer prior to film crystallization prevented degradation in magnetic properties compared to nonpatterned films.

show abstract

Section: -Magnetic Properties Following Deposition Onto Patterned Smentioning

confidence: 99%

Micro-patterning of NdFeB and SmCo magnet films for integration into micro-electro-mechanical-systems

Walther

Marcoux

Desloges

et al. 2009

Journal of Magnetism and Magnetic Materials

Self Cite

View full text Add to dashboard Cite

show abstract

“…Because the deposition rate in electroplating is dependent on the current density within the electroplating seed layer, the thickness of the nickel microstructures is not uniform; consequently, a chemical mechanical polishing ( CMP ) process should be followed to obtain an even height of the microstructure. An alternative approach would be to use a permanent magnet to deposit a thick fi lm of the permanent magnet (e.g., NdFeB), using triode sputtering (see Figure 3.5 ); this method is often used for integrated microscaled rather than macroscaled permanent magnets [43] . The same method is also useful for producing integrated microfl uidic devices for magnetophoresis, although it does not allow the magnetic fi eld to be switched on and off.…”

Section: Design and Microfabrication Processesmentioning

confidence: 99%

Magnetophoretic Biosensing and Separation Using Magnetic Nanomaterials

Kang

Hahn

Kim

et al. 2009

Nanotechnologies for the Life Sciences

View full text Add to dashboard Cite

The sections in this article are Introduction Theory Magnetic Properties of a Material Magnetophoresis High‐Gradient Magnetic Separation Magnetophoresis in Microfluidic Devices Design and Microfabrication Processes Experimental Set‐Up Measurement and Analysis Magnetophoretic Biosensing Magnetophoretic Sandwich Immunoassay Highly Sensitive Biosensors Using HGMS Disease Diagnosis Using Magnetophoretic Assay Systems Multiplexed Magnetophoretic Immunoassay Magnetophoretic Separation Cell Separation and Analysis Separation of Nanomaterials Isomagnetophoresis ( IMP ) Concluding Remarks Acknowledgments

show abstract

“…Usually it has a negligible effect. Nevertheless, it has been shown that scale reduction improves the volume diamagnetic forces allowing levitation of water or bismuth in air with simple micro-magnets [1]. The reverse effect (action-reaction) allows micro-magnets to levitate above diamagnetic material [2].…”

Section: Introductionmentioning

confidence: 99%

Optimization of a 3D micro-accelerometer based on diamagnetic levitation

Pigot

Delinchant

Poulin

et al. 2009

JAE

Self Cite

View full text Add to dashboard Cite

At the micro-scale, diamagnetic effects are of the same order of magnitude or even stronger than weight. Therefore, micro-magnets can levitate above diamagnetic bodies and move freely in the three dimensions of space. The possibilities and limits of a static and permanent levitating magnet are illustrated for the example of a 3-dimensional micro-accelerometer. Optimization is performed in order to fit most current market. It is shown that this technology fulfils the requirements for medium range and short time response markets.

show abstract

Diamagnetic Levitation of Beads and Cells Above Permanent Magnets

Cited by 13 publications

References 5 publications

Micro-patterning of NdFeB and SmCo magnet films for integration into micro-electro-mechanical-systems

Micro-patterning of NdFeB and SmCo magnet films for integration into micro-electro-mechanical-systems

Magnetophoretic Biosensing and Separation Using Magnetic Nanomaterials

Optimization of a 3D micro-accelerometer based on diamagnetic levitation

Contact Info

Product

Resources

About