Magnetic Microsystems: MAG-MEMS

Magnetic interactions offer outstanding performances and provide the base for powerful and efficient Magnetic Micro-Electro-Mechanical Systems (Mag-MEMS). The strong points of magnetic interactions are presented: high energy density and force density, stable forces without power supply, remote actuation, levitation, high-efficiency electrical generation, etc. In the first section, the scale reduction laws are described: in general they are highly favourable to magnetic interactions, particularly, where permanent magnets are involved. As an added bonus, extreme current densities are admissible in integrated μ-coils: this further improves force density in currentdriven devices. In the second section, the basic components of Mag-MEMS are reviewed; technological processes and specifications are only briefly explored here, as they are fully covered in other chapters (μ-magnets, μ-coils, ‘active’ magnetic materials). In the third section, a panorama of applications of Mag-MEMS is explored: switches, motors, generators, commutators, scanners, sensors, etc. Illustrative examples are taken from state-of-the-art research prototypes and preindustrial devices, developed within the Grenoble MEMS and magnetism community.