Patent ID: 9108840
Filing Date: 2015-08-18
Classification: B81B,B81C,H04R

Abstract:
1. A MEMS microphone, comprising: a monolithic silicon chip incorporating an acoustic sensing element and one or more conditioning CMOS integrated circuits, wherein the acoustic sensing element includes a compliant diaphragm, a perforated backplate having through holes, and an air gap between the compliant diaphragm and the backplate, wherein the air gap is located within the monolithic silicon chip; a silicon-based carrier chip having an acoustic cavity, metal through-silicon-via lead-outs and metal pad on both sides of each of the metal through-silicon via lead-outs, wherein the silicon-based carrier chip is seal bonded and electrically connected with the monolithic silicon chip on the backplate side of the monolithic silicon chip; a substrate for flip-chip mounting the assembly of the monolithic chip and the silicon-based carrier chip thereon; a conductive cover having a center cavity bounded with its edges attached and electrically connected to the substrate, the center cavity accommodates the assembly of the monolithic chip and the silicon-based carrier chip; and an acoustic port formed on either the conductive cover or the substrate for an external acoustic wave to reach the acoustic sensing element, wherein the monolithic silicon chip, the silicon-based carrier chip and the acoustic port are configured to cause the external acoustic wave to vibrate the compliant diaphragm of the acoustic sensing element from one side thereof, wherein the monolithic silicon chip comprises a plurality of electrode pads on the backplate side of the monolithic silicon chip, the plurality of electrode pads comprise an electrode pad extracted from signal output of the conditioning CMOS integrated circuit and an electrode pad extracted from the power supply to the conditioning CMOS integrated circuit on the same side, wherein the MEMS microphone also comprises a metal eutectic bonding bonded between the metal pads and the electrode pads so as to bond the silicon-based carrier chip and the monolithic silicon chip.