Micro-electro-mechanical relays-design concepts and process demonstrations

MEMS relays designed for automotive applications were investigated and various fabrication techniques reviewed. Several micro-relay structures, of approximately 2 mm/spl times/1 mm/spl times/0.01 mm, were then made by electroforming with copper as the structural part and gold plated copper as the electrical contact part. Electrostatic actuation was achieved in all designs and on-off switching of small electrical loads (up to 1A, 12 VDC) tested. Various cleanroom electroforming and cleaning processes were discussed to improve contact resistance and structure durability. The various designs were compared for ease of fabrication, electrostatic actuation and switching performance. The feasibility of such MEMS relays in automotive applications was evaluated.