The present invention relates to using an insulator layer between two metal layers of a semiconductor die to provide a micro-electromechanicalsystems (MEMS) device, such as an ohmic MEMS switch or a capacitive MEMS switch. In an ohmic MEMS switch, the insulator layer may be used to reduce metal undercutting during fabrication, to prevent electrical shorting of a MEMS actuator to a MEMS cantilever, or both. In a capacitive MEMS switch, the insulator layer may be used as a capacitive dielectric between capacitive plates, which are provided by the two metal layers. A fixed capacitive element may be provided by the insulator layer between the two metal layers. In one embodiment of the present invention, an ohmic MEMS switch, a capacitive MEMS switch, a fixed capacitive element, or any combination thereof may be integrated into a single semiconductor die.