| Micromachining has been investigated as a fabrication technology for the production of micromachined relays for many years. This research focused on the development of microrelay designs and the fabrication technologies to allow production of a fully integrated magnetically actuated microrelay. Two different electromagnet designs were considered: planar spiral and planar meander electromagnets. A fully integrated magnetically actuated micromachined relay was realized. This device used a single layer planar meander coil to actuate a movable upper magnetically responsive platform. With the planar meander electromagnet normally-open, normally-closed, and multiple-pole microrelays were realized. The minimum current for actuation was 180 mA, resulting in an actuation power of 33 mW. Devices were able to make and break 1.2 A of current through the microrelay contacts when switched electromagnetically by the planar meander electromagnet. Operational lifetimes in excess of 850,000 operations were observed.; The microrelays were analyzed with reluctance theory and finite-element models. These models predict that contact forces in excess of 1 mN may exist in these structures. Contact materials were investigated and are also reported. Gold to gold contacts provided the lowest contact resistance observed. Magnetic materials were also investigated. The materials reported are nickel-iron (permalloy (80/20)), nickel-cobalt (50/50), and nickel-iron-molybdenum. |
