Title:
PRESSURE-RELIEF DIFFERENTIAL PRESSURE SENSOR AND ITS MANUFACTURE
Document Type and Number:
Japanese Patent JP3259102
Kind Code:
B2
Abstract:
PURPOSE: To make it possible to simply manufacture with wide allowance of manufacturing and assembling tolerances by precipitating a diaphragm material on a spacer and then removing the spacer to form a cavity on one surface of a semiconductor substrate.
CONSTITUTION: After a diaphragm material is precipitated on a cavity 23 formed on the front surface of a silicon substrate 10 and charged with a sacrificial material, the sacrificial material is removed, and a free diaphragm is formed. In this case, the floor of the cavity 23 is operated as a first (forward) pressure throttle to limit the deflection amount of the diaphragms 24a responsive to the pressure applied to the upper surface of the diaphragm. Then, a port 33 for transmitting pressure to the bottom of the diaphragm 24a is provided. Further, a cap 35 is fixed to the pole 34 installed on the periphery of the upper surface of the diaphragm 24a as required to form a second (back pressure) throttle, the deflection amount of the diaphragm 24a responsive to the pressure applied to the bottom of the diaphragm 24a is limited.
Inventors:
Clifford Di. Fang
Kevin H. L. Chow
P. Low Harris
John G. Panago
Gary A. Darlouge
Kevin H. L. Chow
P. Low Harris
John G. Panago
Gary A. Darlouge
Application Number:
JP10542992A
Publication Date:
February 25, 2002
Filing Date:
March 30, 1992
Export Citation:
Assignee:
The Foxboro Company
International Classes:
G01L13/06; G01L9/00; G01L19/06; (IPC1-7): G01L13/06; G01L19/06
Domestic Patent References:
| JP59155971A | ||||
| JP6079778A |
Attorney, Agent or Firm:
Yoshiki Ishida