| CPC H04R 7/06 (2013.01) [H04R 1/04 (2013.01); H04R 7/16 (2013.01); H04R 19/04 (2013.01); H04R 2307/023 (2013.01)] | 16 Claims |

|
1. A sealed dual membrane (SDM) structure, comprising:
a substrate;
a first vibrating membrane and a second vibrating membrane disposed on the substrate, the first vibrating membrane, the second vibrating membrane and the substrate together forming a sealed cavity;
a first back electrode plate and a second back electrode plate disposed between the first vibrating membrane and the second vibrating membrane, and
a conductor plate unit disposed between the first back electrode plate and the second back electrode plate;
wherein the first vibrating membrane and the second vibrating membrane are mechanically coupled to the conductor plate unit, and
wherein the conductor plate unit forms a capacitor structure with each of the first back electrode plate and the second back electrode plate; each of the first back electrode plate and the second back electrode plate has a conductive layer and at least one insulator layer facing the conductor plate unit.
|