G01L9/0054

Pressure sensor
11499882 · 2022-11-15 · ·

A pressure sensor includes a sensor chip. The sensor chip has two diaphragms, recessed portions that serve as first pressure inlet chambers disposed so as to respectively adjoin top surfaces of the diaphragms, and recessed portions that serve as second pressure inlet chambers disposed so as to respectively adjoin bottom surfaces of the diaphragms. A cavity is provided in the sensor chip such that, when a difference between pressures respectively applied to a top surface and bottom surface of the diaphragm is zero, an output voltage of a Wheatstone bridge circuit made up of strain gauges provided in the diaphragm is zero.

Mems pressure sensing element with stress adjustors to minimize thermal hysteresis induced by electrical field

A pressure sensing element, including a substrate, a device layer coupled to the substrate, a diaphragm being part of the device layer, and a plurality of piezoresistors coupled to the diaphragm. A plurality of bond pads is disposed on the device layer, and an electrical field shield is bonded to the top of device layer and at least one of the bond pads. At least one stress adjustor is part of the electrical field shield, where the stress adjustor is a cut-out constructed and arranged to reduce thermal hysteresis of the pressure sensing element caused by stress relaxation of the electrical field shield during a cooling and heating cycle. The stress adjustor may be a thin film deposited on top of the electrical field shield, which may apply residual stress to the piezoresistors. The pressure sensing element may include a cavity integrally formed as part of the substrate.

Pressure sensor

The present disclosure enables measurement with satisfactory sensitivity in a low pressure range, and thus accurate measurement in a wider pressure range, by providing a pressure sensor that includes a diaphragm layer and a pressure receiving region formed in the diaphragm layer. In addition, the pressure sensor includes a first piezostrictive element, a second piezostrictive element, a third piezostrictive element, and a fourth piezostrictive element. In addition, the pressure sensor includes a first magnetostrictive element, a second magnetostrictive element, a third magnetostrictive element, and a fourth magnetostrictive element.

Mems Pressure Sensing Element with Stress Adjustors to Minimize Thermal Hysteresis Induced by Electrical Field

A pressure sensing element, including a substrate, a device layer coupled to the substrate, a diaphragm being part of the device layer, and a plurality of piezoresistors coupled to the diaphragm. A plurality of bond pads is disposed on the device layer, and an electrical field shield is bonded to the top of device layer and at least one of the bond pads. At least one stress adjustor is part of the electrical field shield, where the stress adjustor is a cut-out constructed and arranged to reduce thermal hysteresis of the pressure sensing element caused by stress relaxation of the electrical field shield during a cooling and heating cycle. The stress adjustor may be a thin film deposited on top of the electrical field shield, which may apply residual stress to the piezoresistors. The pressure sensing element may include a cavity integrally formed as part of the substrate.

SURFACE STRESS SENSOR, HOLLOW STRUCTURAL ELEMENT, AND METHOD FOR MANUFACTURING SAME

Provided are a surface stress sensor that enables deterioration in measurement precision to be suppressed and a method for manufacturing the same. A surface stress sensor includes: a membrane configured to be bent by applied surface stress; a frame member configured to surround the membrane with gaps interposed therebetween when viewed from the thickness direction of the membrane; at least a pair of coupling portions configured to couple the membrane and the frame member; a flexible resistor configured to be disposed on at least one of the coupling portions and have a resistance value that changes according to bending induced in the coupling portion; and a support base member configured to be connected to the frame member and overlap the frame member when viewed from the thickness direction of the membrane, in which a cavity portion is disposed between the membrane and the support base member.

Methods for fabricating pressure sensors with non-silicon diaphragms

Methods of manufacturing a pressure sensor from an SOI wafer are provided. In preferred embodiments, the methods comprise forming a cavity in a SOI wafer by removing a first portion of a bottom silicon layer on the bottom side of the SOI wafer to a depth of an insulator layer; depositing a layer of a second material over the cavity; removing both the silicon layer and the insulator layer from a top side of the SOI wafer in a first plurality of areas above the cavity to form a diaphragm from the layer of a second material, wherein at least one support structure that spans the diaphragm is formed from material above the cavity that was not removed; and forming at least one piezoresistor in the SOI wafer over an intersection of the support structure and SOI wafer at an outside edge of the diaphragm.

PRESSURE SENSOR INCLUDING A MICROELECTROMECHANICAL TRANSDUCER AND RELATING PRESSURE-DETECTION METHOD
20230104798 · 2023-04-06 · ·

A pressure sensor including: a structure which delimits a main cavity of a closed type, the structure being at least partially deformable as a function of a pressure external to the structure; and a MEMS device, which is arranged in the main cavity and generates an output signal, which is of an electrical type and is indicative of the pressure inside the main cavity.

SEMICONDUCTOR PRESSURE SENSOR AND MANUFACTURING METHOD OF SEMICONDUCTOR PRESSURE SENSOR
20220315415 · 2022-10-06 · ·

A semiconductor pressure sensor includes: a first silicon substrate including a first recessed part; and a second silicon substrate including a diaphragm covering a first space in the first recessed part, the second silicon substrate being configured to hermetically seal the first space. In cross-section, a plurality of second spaces are hermetically sealed in a state of being separated away from the first space between the first silicon substrate and the second silicon substrate, and are provided in one of or each of a first end side and a second end side of the first space.

MEMS sensor
11643324 · 2023-05-09 · ·

A MEMS sensor includes a silicon substrate that has a first surface and a second surface on a side opposite to the first surface and that has a cavity in the first surface, a silicon diaphragm that has a first surface and a second surface on aside opposite to the first surface and in which the second surface is joined directly to the first surface of the silicon substrate, and a piezoresistance formed at the first surface of the silicon diaphragm, and, in the MEMS sensor, a plane orientation of the first surface of the silicon substrate and a plane orientation of the first surface of the silicon diaphragm differ from each other.

STRESS DECOUPLED PIEZORESISTIVE RELATIVE PRESSURE SENSOR AND METHOD FOR MANUFACTURING THE SAME
20170369306 · 2017-12-28 ·

Embodiments provide a MEMS (Micro Electro Mechanical System) pressure sensor comprising a semiconductor substrate, wherein the semiconductor substrate comprises a stress decoupling structure adapted to stress decouple a first portion of the semiconductor substrate from a second portion of the semiconductor substrate, wherein the first portion of the semiconductor substrate comprises a first buried empty space, wherein the second portion of the semiconductor substrate comprises a second buried empty space, and wherein the semiconductor substrate comprises a pressure channel fluidically connecting the first buried empty space and the second buried empty space.