An MEMS acoustic transducer includes a substrate having an opening formed therein, a diaphragm comprising a slotted insulative layer, and a first conductive layer. The slotted insulative layer is attached around a periphery thereof to the substrate and over the opening, and the first conductive layer is disposed on a first surface of the slotted insulative layer. A backplate is separated from the diaphragm and disposed on a side of the diaphragm opposite the substrate.