US 6,584,854 B2 · Pressure sensor and pressure-measuring apparatus using pressure buffering

Abstract

A pressure-detecting chamber 23, a pressure-directing path 25 and a buffer space 24 are formed on the upper face of a main-body-side substrate 22 as recessed portions, and the upper face of the pressure-detecting chamber 23 is covered with a thin-type diaphragm 31, and upper faces of the pressure-directing path 25 and the buffer space 24 are covered with a cover substrate 30. A pressure-introducing unit 26 formed on the lower face of the main-body-side substrate 22 is connected to the lower face of the buffer space 24. The cross-section of the buffer space 24 is greater than the cross-section of the pressure-introducing unit 26, and the capacity of the buffer space 24 is greater than the capacity of the pressure-directing path 25. With this arrangement, it is possible to provide a pressure sensor which can control the response characteristic of the pressure sensor to a pressure change with high precision without causing serious adverse effects on the other characteristics of the pressure sensor, without preventing the miniaturization of the sensor.

Claims11

Dependent claims

A pressure sensor comprising:

a semiconductor substrate having a pressure introduction passage therethrough;
a thin-film diaphragm covering the semiconductor substrate with a predetermined distance therefrom forming a pressure directing path and a pressure detecting chamber therebetween, the thin-film diaphragm covering the pressure detecting chamber being distorted in response to pressure transmitted into the pressure detecting chamber through the pressure introduction passage via the pressure directing path to enable the pressure sensor to detect a pressure based upon a change of the predetermined distance between the semiconductor substrate and the thin-film diaphragm covering the pressure detecting chamber;
and
a buffer concavity formed in the semiconductor substrate at the pressure directing path,
wherein pressure transmitted into the pressure detecting chamber through the pressure introduction passage is buffered in the buffer concavity so that distortion of the thin-film diaphragm covering the pressure detecting chamber due to an instantaneous pressure is prevented.

2 more elements

Dependencies are inferred from the claim text.

Pressure sensor and pressure-measuring apparatus using pressure buffering

Life of this patent

Pressure sensor and pressure-measuring apparatus using pressure buffering

Life of this patent

Abstract

Claims11