Micro-electro-mechanical system microphone, microphone unit and electronic device

A MEMS microphone, comprising:

• a substrate;
• a back electrode plate divided into a center region and an edge region, the edge region comprising a supporting structure;
• and
• a diaphragm located between the substrate and the back electrode plate,
• wherein the supporting structure comprises a supporting portion for supporting a periphery of a diaphragm, and a supporting electrode insulated from the supported diaphragm, and the supporting portion comprises a plurality of supporting bulges arranged from an inner side to an outer side in the edge region, and
• wherein the diaphragm is configured as a stress-free film when no bias is applied, and
• when a bias is applied, a center and the periphery of the diaphragm are both displaced toward the back electrode plate, so that the plurality of supporting bulges support the periphery of the diaphragm, and the supporting electrode is configured to constrain the periphery of the diaphragm on the supporting portion through an electrostatic interaction to support the diaphragm in a clamped manner.