Development of crystalline magnetic thin films for microlevitation

Abstract

In recent years, magnetic levitation is finding interesting applications in various fields related to microdevices. Producing inexpensive microfabricated magnetic films is of high importance to all magnetically levitated microdevices. This paper introduces a microlevitation system and presents the fabrication of Co-Ni-Mn-P films using electrodeposition. The fabrication parameters are varied such that magnetization direction of the film is varied by changing the crystal structure. The magnetic properties of the films such as coercivity, remanence, and maximum energy product demonstrate that hexagonal structure promotes out-of-plane magnetization whereas cubic structure reinforces in-plane magnetization. The performance of the Co-Ni-Mn-P films is evaluated by magnetic levitation experiments of silicon samples. Satisfactory results are obtained toward the goal of realization of a magnetically levitated microgripper.

Micro-force compensation in automated micro-object positioning using adaptive neural networks

“…. Consider the dynamic system of micromanipulator described by (12), for the bounded, continuous desired trajectory with bounded velocity and acceleration. NN controller (13) can guarantee the uniform ultimate boundedness of the close-loop system with the gains satisfying k v − km > 0, and the NN weight tuning algorithms given by:…”

“…Micro-assembly is inevitable in micro-opto-electro-mechanical systems (MOEMS) because of the incompatibility of optics devices with CMOS technology. Other significant applications of micro-assembled systems are seen in biomedicine such as microsurgery [8,9], cell manipulation [10][11][12], cell healing [8], and drug delivery [9]. 3 Author to whom any correspondence should be addressed.…”

“…Non-contact manipulation has been carried out by magnetic levitation of objects [12][13][14]. This solution does not eliminate the complex problem of microsurface forces at the start and target point of micro-object positioning where the object inevitably has to be in contact with another object.…”

Nickel and Nickel-Based Nanoalloy Thin Films from Alcohol-Assisted Chemical Vapor Deposition

“…Ni−Co alloys were theoretically predicted to exhibit superior efficiency as catalysts for the growth of single-walled carbon nanotubes . Other promising applications of Ni−Co alloy thin films include the preparation of microlevitating magnets . In contrast to Ni−Cu alloys, Ni−Co tends to transit from the fcc phase in nickel-rich solid solutions to the hexagonal close-packed (hcp) structure for cobalt-rich alloys. , These Ni−Co alloys were synthesized as thin films using electrochemical deposition − and sputtering or as particles using microemulsion and polyol processes .…”

“…Other promising applications of Ni−Co alloy thin films include the preparation of microlevitating magnets . In contrast to Ni−Cu alloys, Ni−Co tends to transit from the fcc phase in nickel-rich solid solutions to the hexagonal close-packed (hcp) structure for cobalt-rich alloys. , These Ni−Co alloys were synthesized as thin films using electrochemical deposition − and sputtering or as particles using microemulsion and polyol processes . Nickel-rich Ni−Co alloys exhibit superior efficiency and stability as oxygen-evolution reaction catalyst, whereas cobalt-rich alloys show a markedly high wear resistance and low friction coefficient due to the hcp structure …”