Pressure sensor and manufacturing method for the same
AssigneeInvenSense, Inc.
InventorsYoshitaka Sasaki, Jotaro Akiyama, Sal Akram, Yaoching Wang, Wang Shen Su, Tsung Lin Tang, Ting-Yuan Liu, Yuki Shibano, Chung-Hsien Lin
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Abstract
A pressure sensor includes a first electrode, a plurality of cavities, and a second electrode. The second electrode is disposed opposite the first electrode through the plurality of cavities. The second electrode includes a flat structure spanning two adjacent cavities of the plurality of cavities.
Claims20
A pressure sensor comprising:
- a first electrode;
- a plurality of cavities;
- and
- a second electrode disposed opposite the first electrode through the plurality of cavities and including a single, continuous flat structure spanning at least two adjacent cavities of the plurality of cavities.
A manufacturing method for a pressure sensor, the pressure sensor comprising a first electrode, a plurality of cavities, and a second electrode disposed opposite the first electrode through the cavity, the manufacturing method comprising:
- forming the first electrode;
- forming a sacrificial layer over the first electrode;
- forming the second electrode over the sacrificial layer;
- forming a vent hole in the second electrode, to expose a top surface of the sacrificial layer;
- and
- forming the plurality of cavities by etching the sacrificial layer and expelling an etched material from the vent hole, wherein the sacrificial layer includes a first layer, and a second layer disposed between the first electrode and the first layer and having a higher etching rate than the first layer, the second electrode including a single, continuous flat structure spanning at least two adjacent cavities of the plurality of cavities.
Dependencies are inferred from the claim text.