Patent ID: 6738484
Filing Date: 2004-05-18
Classification: H04R

Abstract:
A pressure responsive device comprising:a package including a storage chamber in an interior of the package; means for introducing an outside pressure into the storage chamber; a semiconductor substrate placed in the storage chamber; and a capacitor placed on the semiconductor substrate and having a capacitance which varies according to the outside pressure introduced into the storage chamber, wherein a concave having a bottom surface and a peripheral surface surrounding the concave are formed on one main surface of the semiconductor substrate, the capacitor includes a fixed electrode membrane placed on the bottom surface of the concave and a vibrating electrode membrane fixed on an entirety of the peripheral surface completely covering the concave and facing the fixed electrode membrane through a space, and the vibrating electrode membrane vibrates according to a variation in the outside pressure introduced into the storage chamber, and wherein the concave and the vibrating electrode membrane form a communication groove running horizontally from the concave to an outer peripheral edge of the semiconductor substrate formed on the one main surface of the semiconductor substrate.