| MEMS relay is smaller, cheaper, and lighter than regular devices. Compare with other driving method, magnetic driving has advantages such as stronger driving force, remote driving without contact, and better compatibility with micro electronic processing. These give magnetic driver great research value and application potential.In this paper, a new type MEMS magnetic relay is designed. It is composed of two parts: a magnetic driving chip and a movable permalloy cantilever. The device we made have following characteristics: it has very small volume(surface 1mm×1mm) and is highly integrated. It uses double layers Cu coils and magnetized permalloy core to increase the driving force, uses polymide for isolation. It is a new structure with outer"O"shape underlayer and one-end-fixed movable cantilever.The magnetic circuit theory is introduced. We consider the following parameters: gap magnetic flux leakage, the distribution effect of induction potential and the nonlinear permeability for permalloy. Based on the distributed method, the magnetic circuit model is setup. Matlab program is used to calculate how these structure parameter such as permalloy core height, Cantilever thickness and gap width influence the device capacity. Cantilever thickness is the key factor. The optimal structure parameters are determined.Micro-electroforming and a polymide isolation processing are used to fabricate the driver. Backside calibration is introduced in lithography to increase the precision. Two designs:"releasing cantilever"and"flip chip"are compared for cantilever Manufacture. The"flip chip"design use silicon body wet etching and metal electroplating. In micro processing, some possible problems and defections caused by device miniature are introduced, along with solutions. Proved the structure design and manufacture feasibility for driver miniature.
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