Structure of micro-electro-mechanical-system microphone

A structure of micro-electro-mechanical-system (MEMS) microphone, comprising a substrate, a dielectric layer on the substrate, a diaphragm, and a back-plate on the dielectric layer, wherein the diaphragm comprises:

• a sensing part held by a dielectric layer to respond a pressure variance from an acoustic signal, wherein the sensing part comprises at least a diaphragm opening;
• and
• at least one air valve plate, disposed within the diaphragm opening at a same height of the sensing part, wherein the air valve plate comprises:
• a base plate affixed to the back-plate;
• a swayable plate;
• and
• a spring joint connected between the base plate and the swayable plate,
• wherein the air valve plate with the spring joint is activated when suffering an air flow other than the acoustic signal, and the swayable plate vibrates in response to a pressure of the air flow.