Magnetic Nanoparticle Dosing of MEMS Structures by Solvent Evaporation in Capillaries

This paper describes a low cost method to deliver magnetic nanoparticle materials using a liquid suspension deposition into ¿m-sized structures that would comprise an inductor core. The delivery structure consists of a well and capillary where the well is the target for liquid delivery. Prior theory describing the dosing of MEMS capillaries with polymers is extended to NiFe₂O₄ nanoparticles in suspension for dosing capillaries constituting inductor type passives with ~200 times larger volumes (2 mm × 15 ¿m × 10 ¿m). Well and capillary structures were dosed with the magnetic nanoparticles suspension with and without the presence of a permanent magnetic field. Magnetization measurements show a difference in relative permeabilities of 4.2 and 3.3 with and without the presence of the magnetic field, respectively.