A MEMS structure and a method for operation a MEMS structure are disclosed. In accordance with an embodiment of the present invention, a MEMS structure comprises a substrate, a backplate, and a membrane comprising a first region and a second region, wherein the first region is configured to sense a signal and the second region is configured to adjust a threshold frequency from a first value to a second value, and wherein the backplate and the membrane are mechanically connected to the substrate.