COUNTER ELECTRODE STRUCTURE AND DUAL-MEMBRANE MEMS MICROPHONE

The present invention provides a counter electrode structure and a dual-membrane MEMS microphone. The dual-membrane MEMS microphone comprises a substrate and a capacitor system. The capacitor system comprises a first electrode membrane and a second electrode membrane which are arranged at an interval to form an accommodating cavity, and the two electrode membranes have corrugated cross-sectional shapes in the radial direction. The wave crest of one electrode membrane is connected to the wave trough of the other electrode membrane to form a supporting body. The capacitor system further comprises a counter electrode structure suspended in the accommodating cavity. The counter electrode structure comprises a plurality of circumferential beams arranged at intervals from inside to outside and a plurality of radial beams connected to the circumferential beams and extending from inside to outside, a via hole extending around the center of the counter electrode structure is formed between every two adjacent circumfer