Micromachined thick permanent magnet arrays on silicon wafers

Abstract

Using micromachining and electroplating techniques, micromachined thick CoNiMnP-based permanent magnet arrays have been designed, fabricated, and characterized for magnetic microelectromechanical systems (MEMS) device applications. The electroplated magnet arrays contain 1,500 magnets of 40 /spl mu/m/spl times/40 /spl mu/m/spl times/50 /spl mu/m in a cubic shape on the silicon substrate of 2.5 mm/spl times/2.5 mm, where the magnets have shown a fairly high magnetic vertical coercivity of 800-1300 Oe, a retentivity of 2.0-3.0 kG, a maximum flux saturation of 12.0-13.0 kG, and a maximum energy density of 14 kJ/m/sup 3/.