Patent ID: 9207138
Filing Date: 2015-12-08
Classification: B81B,B81C,G01L

Abstract:
1. A method for fabricating a capacitive pressure sensor, comprising: providing a substrate; forming a trench in a surface of the substrate; forming a first electrode including a first sub-electrode and a second sub-electrode on a side surface of the trench; forming a first sacrificial layer on the first electrode; etching the substrate under the bottom of the trench to form an etching hole in the substrate under the bottom of the trench; forming a second electrode on a side surface and a bottom surface of the trench, a portion of the bottom of the trench, and a side surface of the first sacrificial layer; forming a second sacrificial layer on the second electrode and filling up the trench and the etching hole; forming a first sealing layer on the second sacrificial layer; removing the first sacrificial layer to form a first chamber between the first electrode and the second electrode; planarizing the substrate or etching the substrate to expose the sacrificial layer on the bottom surface of the etching hole; removing the second sacrificial layer in the trench and the etching hole to form a second chamber in the second electrode; and forming a second sealing layer on the other surface of the substrate to seal the second chamber.