Abstract: A MEM device has a movable element (30), a pair of electrodes (e1, e2) to move the movable element, one electrode having an independently movable section (e3), resiliently coupled to the rest of the respective electrode to provide additional resistance to a pull in of the electrodes. This can enable a higher release voltage Vrel, and thus reduced risk of stiction. Also, a ratio of Vpi to Vrel can be reduced, and so a greater range of voltage is available for movement of the movable element. This enables faster switching. The area of the independently movable section is smaller than the rest of the electrode, and the spring constant of the resilient coupling is greater than that of the flexible support. Alternatively, the movable element can have a movable stamp section resiliently coupled and protruding towards the substrate to provide an additional resistance to pull in when it contacts the substrate.

Abstract: A micro-electromechanical device has a substrate (10), a movable element, movable towards the substrate by electrostatic forces on electrodes, facing surfaces of the movable element and the substrate being shaped such that one or more venting channels (VC) are defined by the facing surfaces when they are in a closed position, configured to enable fluid between the facing surfaces to flow across the facing surfaces, to enter or exit the area between the facing surfaces. Such channels can enable fluid damping of the movement of the moveable element to be controlled. Increasing the flow entering or exiting the area between the facing surfaces, can reduce such damping, and hence increase speed of opening and closing of the device. The channels can connect to holes in the electrodes.

Abstract: A MEM device has a movable element (30), a pair of electrodes (e1, e2) to move the movable element, one electrode having an independently movable section (e3), resiliently coupled to the rest of the respective electrode to provide additional resistance to a pull in of the electrodes. This can enable a higher release voltage Vrel, and thus reduced risk of stiction. Also, a ratio of Vpi to Vrel can be reduced, and so a greater range of voltage is available for movement of the movable element. This enables faster switching. The area of the independently movable section is smaller than the rest of the electrode, and the spring constant of the resilient coupling is greater than that of the flexible support. Alternatively, the movable element can have a movable stamp section resiliently coupled and protruding towards the substrate to provide an additional resistance to pull in when it contacts the substrate.