US 10,371,591 B2 · Method and apparatus for correction of pressure sensors

Abstract

A differential pressure sensor includes one or more semiconductor dies which are thinned at portions of the die to create a chamber defining a sensitive diaphragm, having piezoresistive elements defined at a surface of the diaphragm. A first diaphragm is in fluid communication with a first fluid on an upper surface of the first diaphragm and is in fluid communication with a second fluid on a lower surface of the first diaphragm. A second diaphragm is in fluid communication with ambient pressure at an upper and a lower surface of the second diaphragm. The piezoresistive elements corresponding to the second diaphragm are electrically connected to the piezoresistive elements of the first diaphragm so as to compensate the output of the second diaphragm with respect to the output of the first diaphragm.

Claims20

Dependent claims

A pressure sensor comprising:

a first pressure sensing die comprising a semiconductor material and having a first sensitive diaphragm;
a second pressure sensing die comprising a semiconductor material and having a second sensitive diaphragm;
and
a housing containing the first pressure sensing die and the second pressure sensing die, the housing containing a first fluid at a first pressure in fluid communication with a first surface of the first sensitive diaphragm of the first pressure sensing die, and a second fluid at a second pressure in fluid communication with a second surface of the first sensitive diaphragm of the first pressure sensing die, and wherein a first and second surface of the second sensitive diaphragm of the second pressure sensing die are in fluid communication with a third fluid at a third pressure.

1 more element

A differential pressure sensor comprising:

a sensor housing including a base plate having an aperture defined therein, wherein a first side of the base plate is configured to be in fluid communication with a first fluid at a first pressure at the aperture and a second side of the base plate is configured to be in fluid communication with a second fluid at a second pressure at the aperture;
a pressure sensing die assembly attached to the first side of said base plate, the pressure sensing die assembly comprising:
a pressure sensing die attached to the base plate, the pressure sensing die comprising:
a first chamber defining a first diaphragm having a first upper side configured to be in fluid communication with said first fluid and a lower side configured to be in fluid communication with the aperture and the second fluid;
at least one pressure sensitive electrical element formed in or on the first diaphragm, the at least one pressure sensitive electrical element exhibiting varying resistance responsive to deflection of the first diaphragm representative of a differential pressure between the first pressure and the second pressure;
a second chamber defining a second diaphragm including a second upper side configured to be in fluid communication with an ambient pressure and a second lower side configured to be in fluid communication with the ambient pressure;
at least one pressure sensitive electrical element formed in or on the second diaphragm, the at least one pressure sensitive electrical element exhibiting varying resistance responsive to deflection of said second diaphragm representative of a common mode error corresponding to the pressure sensing die assembly;
and
one or more electrical conductors electrically connected to one or both of the at least one pressure sensitive electrical element bonded to the first diaphragm and the at least one pressure sensitive electrical element bonded to the second diaphragm, the one or more electrical conductors configured to output a common mode error corrected differential pressure output.

6 more elements

Dependencies are inferred from the claim text.

Method and apparatus for correction of pressure sensors

Life of this patent

Method and apparatus for correction of pressure sensors

Life of this patent

Abstract

Claims20