Structure of MEMS electroacoustic transducer and fabricating method thereof

A method of fabricating a structure of micro-electro-mechanical systems (MEMS) electroacoustic transducer, comprising:

• providing a substrate comprising a circuit region, a MEMS device region, and a vent hole region;
• forming a first metal interconnect structure on the substrate in the circuit region;
• forming a first dielectric layer structure on the substrate in the MEMS device region and the vent hole region and a conductive pattern in the first dielectric layer structure in the MEMS device region;
• forming a diaphragm on the first dielectric layer structure in the MEMS device region, wherein the diaphragm has a plurality of openings;
• forming a vent hole layer on the first dielectric layer structure in the vent hole region, wherein the vent hole layer has a vent hole;
• forming a sealing layer on the diaphragm for sealing the diaphragm;
• forming a second metal interconnect structure on the first metal interconnect structure;
• forming a second dielectric layer structure directly on the sealing layer in the MEMS device region and on the vent hole layer in the vent hole region;
• forming a hard mask layer on the second metal interconnect structure;
• and
• removing the first dielectric layer structure and the second dielectric layer structure by the use of the hard mask layer as a mask.