Patent ID: 7571651

Claim:
A method for manufacturing a capacitive pressure sensor, the method comprising steps of: etching a front surface of a silicon substrate to a designated depth, depositing an etching stopper on a rear surface of the silicon substrate to stop etching the rear surface, depositing an upper electrode of a capacitor on the surface of the etching stopper, wherein said upper electrode is made of doped polysilicon, depositing an insulating layer of the capacitor on the surface of the upper electrode, wherein said insulating layer is made of hafnium oxide, depositing a lower electrode of the capacitor on the surface of the insulating layer to form the capacitor, wherein said lower electrode is made of doped polysilicon, forming a metal pad electrode on the front surface of a glass substrate, hybrid-bonding the lower electrode of the capacitor of the silicon substrate to the metal pad electrode of the glass substrate using an electric (anodic) bonding method, etching a rear surface of bonded silicon substrate to the glass substrate for selectively exposing the etching stopper to form a membrane, wherein the rear surface of the bonded silicon substrate is etched by anisotropic chemical etching, and removing the exposed region of the etching stopper by wet etching, so that the capacitor is formed a shape of membrane having three-layer structure to be highly sensitive for a pressure variation.