US 11,889,248 B2
MEMS microphone
Zhenkui Meng, Shenzhen (CN); and Zhengyan Liu, Shenzhen (CN)
Assigned to AAC Acoustic Technologies (Shenzhen) Co., Ltd., Shenzhen (CN)
Filed by AAC Acoustic Technologies (Shenzhen) Co., Ltd., Shenzhen (CN)
Filed on Dec. 9, 2019, as Appl. No. 16/708,409.
Claims priority of application No. 201822279342.8 (CN), filed on Dec. 31, 2018.
Prior Publication US 2020/0213690 A1, Jul. 2, 2020
Int. Cl. H04R 1/02 (2006.01); H04R 19/00 (2006.01); H04R 19/01 (2006.01)
CPC H04R 1/021 (2013.01) [H04R 19/005 (2013.01); H04R 19/016 (2013.01); H04R 2201/003 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A MEMS microphone, including:
a base with a back cavity;
an electric capacitance system arranged on the base, including a back plate, a first diaphragm and a second diaphragm opposite to the back plate and arranged on an upper and lower sides of the back plate;
an insulation layer isolating the base, the back plate, the first diaphragm and the second diaphragm;
a sealing space formed between the first diaphragm and the second diaphragm; wherein
the back plate comprises an intermediate main body area, a first edge area on one side of the intermediate main body area and a second edge area on the other side of the intermediate main body; a plurality of acoustic through holes are spaced in the intermediate main body area, and a plurality of supporting components penetrates through the acoustic through holes for connecting the first diaphragm to the second diaphragm, the MEMS microphone comprises a first release barrier structure located in the first edge area and penetrating the back plate, the first release barrier structure isolates the acoustic through hole and the insulation layer; the MEMS microphone further comprises a plurality of second release barriers located in the second edge area and spaced on the back plate; the second release barrier structure isolates the acoustic through hole from the insulation layer, a pressure in the sealing space is equal to an external pressure.