A microelectromechanical system (MEMS) resonator or filter including a first conductive layer, one or more electrodes patterned in the first conductive layer which serve the function of signal input, signal output, or DC biasing, or some combination of these functions, an evacuated cavity, a resonating member comprised of a lower conductive layer and an upper structural layer, a first air gap between the resonating member and one or more of the electrodes, an upper membrane covering the cavity, and a second air gap between the resonating member and the upper membrane.