Mems microphone and method for forming the same

A method for forming a Micro-Electro-Mechanical System (MEMS) microphone, comprising:

• providing a first substrate, wherein the first substrate comprises a first surface and a second surface opposite to the first surface, the first substrate comprises at least one conductive layer located at the side of the first surface of the first substrate;
• providing a second substrate, wherein the second substrate comprises a third surface and a fourth surface opposite to the third surface, the second substrate comprises a second base and a sensitive electrode located on or above or in the second base, the second substrate comprises a sensitive region in which the sensitive electrode is located, the sensitive electrode is located at the side of the third surface of the second substrate;
• bonding the first surface of the first substrate and the third surface of the second substrate to each other;
• thinning the second substrate from the fourth surface of the second substrate and removing the second base partially to form a fifth surface opposite to the third surface of the second substrate, after the first surface of the first substrate and the third surface of the second substrate are bonded to each other;
• forming a cavity between the first substrate and the sensitive region of the second substrate;
• and
• forming a first conductive plug from the side of the fifth surface of the second substrate, with the first conductive plug passing through to at least one of the conductive layers, wherein the first conductive plug is used to form an electrical connection between the conductive layer and the sensitive electrode.

A Micro-Electro-Mechanical System (MEMS) microphone, comprising:

• a first substrate, wherein the first substrate comprises a first surface and a second surface opposite to the first surface, the first substrate comprises at least one conductive layer located at the side of the first surface of the first substrate;
• a second substrate, wherein the second substrate comprises a third surface and a fifth surface opposite to the third surface, the second substrate comprises a sensitive electrode, the second substrate comprises a sensitive region in which the sensitive electrode is located, the first surface of the first substrate and the third surface of the second substrate are bonded to each other;
• a cavity located between the first substrate and the sensitive region of the second substrate;
• and
• a first conductive plug formed from the side of the fifth surface of the second substrate and passing through to at least one of the conductive layers, wherein the first conductive plug is used to form an electrical connection between the conductive layer and the sensitive electrode.

A Micro-Electro-Mechanical System (MEMS) microphone, comprising:

• a first substrate, wherein the first substrate comprises a first surface and a second surface opposite to the first surface, the first substrate comprises at least one conductive layer located at the side of the first surface of the first substrate;
• a second substrate, wherein the second substrate comprises a third surface and a fifth surface opposite to the third surface, the second substrate comprises a second base and a sensitive electrode located on or above or in the second base, the second substrate comprises a sensitive region in which the sensitive electrode is located, the first surface of the first substrate and the third surface of the second substrate are bonded to each other;
• a cavity located between the first substrate and the sensitive region of the second substrate;
• and
• a first conductive plug formed from the side of the fifth surface of the second substrate and passing through to at least one of the conductive layers, wherein the first conductive plug is used to form an electrical connection between the conductive layer and the sensitive electrode.