MEMS microphone and method for manufacturing the same
A method for manufacturing a semiconductor device includes providing a semiconductor structure including a first electrode layer, forming a sacrificial layer on the first electrode layer, the sacrificial layer including a recess having a pointed bottom defining a depth, forming a second electrode layer on the sacrificial layer, the second electrode layer including a first opening exposing the recess, and forming a support layer filling the recess, the first opening, and on the second electrode layer. A portion of the support layer filling the recess forms a stopper having a height equal to the depth of the recess. The method also includes forming a second opening extending through the support layer and the second electrode layer and exposing a surface of the sacrificial layer, and removing a portion of the sacrificial layer to form a cavity.
1. A semiconductor device, comprising:
a first electrode layer;
a sacrificial layer on the first electrode layer and including an opening exposing a surface of the first electrode layer;
a second electrode layer on the sacrificial layer and on the opening;
a cavity formed by the first electrode layer, the sacrificial layer, and the second electrode layer;
a first opening extending through the second electrode layer and to the cavity;
a support layer on the second electrode layer and having a stopper extending through the first opening and protruding into the cavity, the stopper having a pointed end; and
a second opening extending through the support layer and the second electrode layer and to the cavity.
2. The semiconductor device of claim 1 , wherein the sacrificial layer comprises a first sacrificial layer on the first electrode layer and a second sacrificial layer on the first sacrificial layer.
3. The semiconductor device of claim 2 , wherein the first sacrificial layer and the second sacrificial layer each comprise a dielectric material.
4. The semiconductor device of claim 3 , wherein the dielectric material comprises silicon oxide, silicon oxynitride, or ethyl orthosilicate.
5. The semiconductor device of claim 1 , wherein the through hole extends through the first electrode layer.
6. The semiconductor device of claim 1 , wherein the first electrode layer and the second electrode layer each comprise polysilicon or monocrystalline silicon.
7. The semiconductor device of claim 1 , wherein the support layer comprises silicon nitride.
8. The semiconductor device of claim 1 , wherein the first opening and the second opening each comprise a plurality of openings.