James Tjanmeng Suminto - West Covina CA, US Mohammad Yunus - Castro Valley CA, US
Assignee:
S3C, Inc. - Sunnyvale CA
International Classification:
G01L 9/06
US Classification:
73727
Abstract:
A pressure sensor is described with sensing elements electrically and physically isolated from a pressurized medium. An absolute pressure sensor has a reference cavity, which can be at a vacuum or zero pressure, enclosing the sensing elements. The reference cavity is formed by bonding a recessed cap wafer with a gauge wafer having a micromachined diaphragm. Sensing elements are disposed on a first side of the diaphragm. The pressurized medium accesses a second side of the diaphragm opposite to the first side where the sensing elements are disposed. A spacer wafer may be used for structural support and stress relief of the gauge wafer. In one embodiment, vertical through-wafer conductive vias are used to bring out electrical connections from the sensing elements to outside the reference cavity. In an alternative embodiment, peripheral bond pads on the gauge wafer are used to bring out electrical connections from the sensing elements to outside the reference cavity. In various embodiments, a regular silicon-on-insulator wafer or a double silicon-on-insulator wafer may be used as the gauge wafer, and appropriate micromachining steps are adopted to define the diaphragm.
Silicon Sensing Structure To Detect Through-Plane Motion In A Plane Of Material With Thermal Expansion Substantially Different From That Of Silicon
James Tjan-Meng Suminto - West Covina CA, US Leslie Bruce Wilner - Palo Alto CA, US
Assignee:
Meggitt (San Juan Capistrano), Inc. - San Juan Capistrano CA
International Classification:
G01L 9/06
US Classification:
73727, 73715, 73721
Abstract:
A pressure transducer is provided that has a transducer body with a rim, a diaphragm that deflects in response to pressure and a sensor bonded to the diaphragm at the rim and at a center of the diaphragm. The sensor detects deflection of the metal diaphragm. The sensor and diaphragm are made of different materials. A thermal expansion difference between the sensor and the diaphragm is accommodated by flexures in the sensor that accept relative motion in a radial direction of the metal diaphragm with little effect on a sensitivity of the silicon structure to motion in an axial direction of the diaphragm.
Media-Compatible Electrically Isolated Pressure Sensor For High Temperature Applications
James Tjanmeng Suminto - West Covina CA, US Mohammad Yunus - Castro Valley CA, US
Assignee:
S3C, Inc. - Sunnyvale CA
International Classification:
H05K 3/36
US Classification:
29830, 29 2535, 29594, 29852
Abstract:
A method for manufacturing a Micro-Electro-Mechanical System pressure sensor. The method includes forming a gauge wafer including a diaphragm and a pedestal region. The method includes forming an electrical insulation layer disposed on a second surface of the diaphragm region and forming a plurality of sensing elements patterned on the electrical insulation layer disposed on the second surface in the diaphragm region. The method includes forming a cap wafer with a central recess in an inner surface and a plurality of through-wafer embedded vias made of an electrically conductive material in the cap wafer. The method includes creating a sealed cavity by coupling the inner recessed surface of the cap wafer to the gauge wafer, such that electrical connections from the sensing elements come out to an outer surface of the cap wafer through the vias. The method includes attaching a spacer wafer with a central aperture to the pedestal region with the central aperture aligned to the diaphragm region.
Media-Compatible Electrically Isolated Pressure Sensor For High Temperature Applications
A method for manufacturing a Micro-Electro-Mechanical System pressure sensor, including forming a gauge wafer including a diaphragm and a pedestal region. The method includes forming an electrical insulation layer disposed on a second surface of the diaphragm region and forming a plurality of sensing elements patterned on the electrical insulation layer disposed on the second surface in the diaphragm region, forming a cap wafer with a central recess in an inner surface and a plurality of through-wafer embedded vias made of an electrically conductive material in the cap wafer, creating a sealed cavity by coupling the inner recessed surface of the cap wafer to the gauge wafer, such that electrical connections from the sensing elements come out to an outer surface of the cap wafer through the vias, and attaching a spacer wafer with a central aperture to the pedestal region with the central aperture aligned to the diaphragm region.
Leslie Wilner - Palo Alto CA, US Andrew Meyer - Rockwood TN, US James Suminto - Fremont CA, US Joseph Fragala - San Jose CA, US
Assignee:
Endevco Corporation - San Juan Capistrano CA
International Classification:
H01L035/02 H01L035/34
US Classification:
136/224000, 136/232000, 136/201000
Abstract:
A radiation sensor which includes a thermopile for detecting radiant energy. The thermopile and a support rim for the thermopile are fabricated as an integrated unit to form a support chip. The support chip is mated to a mating chip so that the thermopile is positioned in an inner cavity region of the radiation sensor. The sensor has a window which permits the transmission of radiant energy into the enclosure such that the radiant energy impinges upon a central absorber region of the thermopile.
System And Method For Minimizing Deflection Of A Membrance Of An Absolute Pressure Sensor
Javed Hussain - Cupertino CA, US Mohammad Yunus - Castro Valley CA, US James T. Suminto - West Covina CA, US
Assignee:
S3C, Inc. - Sunnyvale CA
International Classification:
B81B 7/00
US Classification:
257420
Abstract:
A Micro-Electro-Mechanical System (MEMS) pressure sensor is disclosed, comprising a gauge wafer, comprising a micromachined structure comprising a membrane region and a pedestal region, wherein a first surface of the micromachined structure is configured to be exposed to a pressure medium that exerts a pressure resulting in a deflection of the membrane region. The gauge wafer also comprises a plurality of sensing elements patterned on the electrical insulation layer on a second surface in the membrane region, wherein a thermal expansion coefficient of the material of the sensing elements substantially matches with a thermal expansion coefficient of the material of the gauge wafer. The pressure sensor comprises a cap wafer coupled to the gauge wafer, which includes a recess on an inner surface of the cap wafer facing the gauge wafer that defines a sealed reference cavity that encloses and prevents exposure of the sensing elements to an external environment.