Multi-floor type MEMS microphone

A multi-floor type micro-electromechanical system (MEMS) microphone, comprising:

• a housing formed by a stack of a first circuit board, a plurality of second circuit boards, a plurality of third circuit boards and a fourth circuit board and provided with a first cavity, a second cavity vertically communicated with the first cavity and having a vertical cross-sectional area smaller than a vertical cross-sectional area of the first cavity, and a sound hole disposed at the first circuit board or the fourth circuit board;
• a MEMS transducer posited in the housing and electrically connected with the housing via a first trace layer;
• and
• an application-specific integrated circuit (ASIC) chip posited in the housing and electrically connected with the housing;
• wherein the plurality of second circuit boards and the plurality of third circuit boards are sandwiched in between the first circuit board and the fourth circuit board, and the first trace layer is extended through at least one of the plurality of the second circuit boards and the plurality of third circuit boards.