A MEMS device and fabrication method are disclosed. A bottom substrate having an insulating layer sandwiched between an upper layer and a lower layer may be bonded to a device layer. One or more portions of the upper layer may be selectively removed to form one or more device cavities. Conductive vias may be formed through the lower layer at locations that underlie the one or more device cavities and electrically isolated from the lower layer. Devices may be formed from the device layer. Each device overlies a corresponding device cavity. Each device may be connected to the rest of the device layer by one or more corresponding hinges formed from the device layer. One or more electrical contacts may be formed on a back side of the lower layer. Each contact is electrically connected to a corresponding conductive via.