Stress sensor, structural health monitoring system for constructions and process for manufacturing a stress sensor
AssigneeSTMicroelectronics S.r.l.
InventorSanto Alessandro Smerzi
Life of this patent
Estimating the term…
Abstract
A stress sensor includes: a substrate, having a face and a recess, open to the face; and a sensor chip of semiconductor material, housed in the recess and bonded to the substrate, the sensor chip being provided with a plurality of sensing components of piezoresistive material. The substrate has a thickness which is less by at least one order of magnitude with respect to a main dimension of the face. Further, the sensor chip has a thickness which is less by at least one order of magnitude with respect to the thickness of the substrate, and a Young's module of the substrate and a Young's module of the sensor chip are of the same order of magnitude.
Claims20
A stress sensor, comprising:
- a substrate having a first surface;
- a recess in the first surface of the substrate, having a second surface, a first portion, and a second portion, the first portion being in a bottom wall of the second portion, and the first portion being deeper and narrower than the second portion;
- and
- a sensor chip of semiconductor material in the recess and coupled to the second surface of the recess, the sensor chip having a thickness smaller by at least one order of magnitude than a thickness of the substrate, the substrate and sensor chip having respective Young's moduli of a same order of magnitude, and a distance between vertical surfaces of the sensor chip and of the second portion is of a same order of magnitude as a main dimension of the sensor chip;
- and
- a hard die-attach layer coupling the sensor chip to the substrate, the first portion of the recess having a depth greater than a thickness of a stack formed by the sensor chip and the hard die-attach layer.
A stress sensor, comprising:
- a ceramic substrate having a recess in a first surface of the ceramic substrate, the recess having a first portion and a second portion, the first portion having a second surface, the second portion having a bottom wall, the first portion is provided in the bottom wall of the second portion;
- and
- a stack of a sensor chip of a semiconductor material and a hard die-attach layer in the recess, the hard die-attach layer bonded to the second surface of the recess that is between the ceramic substrate and the hard die-attach layer, the sensor chip attached to the ceramic substrate through the hard die-attach layer, wherein:
- the ceramic substrate has a thickness smaller by at least one order of magnitude than a main dimension of the surface;
- and
- the sensor chip has a thickness smaller by at least one order of magnitude than the thickness of the ceramic substrate.
A method, comprising:
- forming a recess on a first surface of a substrate of a ceramic material, the recess having a first portion having a second surface and a second portion having a bottom wall, the first portion being in the bottom wall;
- and
- coupling a sensor chip to the second surface of the recess, the sensor chip including a plurality of sensing components of piezoresistive material, the sensor chip having a thickness smaller by at least one order of magnitude than a thickness of the substrate, and the substrate and the sensor chip having respective Young's moduli of a same order of magnitude.
A sensor, comprising:
- a substrate;
- a recess in the substrate, the recess having a surface;
- a hard die-attach layer bonded to the surface of the recess;
- and
- a sensor chip of semiconductor material in the recess and bonded to the substrate via the hard die-attach layer, the surface of the recess between the sensor chip and the substrate, the sensor chip having a thickness smaller by at least one order of magnitude than a thickness of the substrate, and the substrate and sensor chip having respective Young's moduli of a same order of magnitude, the recess includes a first portion and a second portion, the first portion being deeper and narrower than the second portion, the first portion being between the substrate and the second portion.
Dependencies are inferred from the claim text.