Strain gauge and strain measurement assembly

Patent metadata

Field	Value
Publication number	US-11933683-B2
Application number	US-202017011352-A
Country	US
Kind code	B2
Filing date	Sep 3, 2020
Priority date	Sep 3, 2020
Publication date	Mar 19, 2024
Grant date	Mar 19, 2024

Abstract

A strain gauge includes a resistor formed of a doped silicon material, a conductive shield, and an isolation element disposed between the resistor and the conductive shield. The isolation element electrically isolates the resistor from the conductive shield.

First claim

What is claimed is:

1. A strain gauge, comprising:
a resistor formed of a doped silicon material;
a conductive shield; and
an isolation element disposed between the resistor and the conductive shield and electrically isolating the resistor from the conductive shield, the resistor and the isolation element are formed within a single silicon substrate.

2. The strain gauge of claim 1 , wherein the resistor is a p-type doped section of the silicon substrate.

3. The strain gauge of claim 2 , wherein the isolation element is an n-type doped section of the silicon substrate forming a p-n junction with the p-type doped section.

4. The strain gauge of claim 3 , wherein the conductive shield is formed within the single silicon substrate.

5. The strain gauge of claim 4 , wherein the conductive shield is an n+-type highly doped section of the silicon substrate.

6. The strain gauge of claim 3 , wherein the conductive shield is a metal layer on which the silicon substrate is disposed.

7. The strain gauge of claim 3 , wherein the isolation element surrounds a lower side and a plurality of lateral sides of the resistor.

8. The strain gauge of claim 7 , further comprising a guard ring formed within the single silicon substrate.

9. The strain gauge of claim 8 , wherein the guard ring is an n+-type highly doped section of the silicon substrate section disposed at a same height as the resistor along a height direction and spaced apart from the lateral sides of the resistor in a lateral direction perpendicular to the height direction.

10. The strain gauge of claim 1 , wherein the resistor is a p-type doped silicon layer and the isolation element is an oxide on which the p-type doped silicon layer is disposed.

11. The strain gauge of claim 10 , wherein the conductive shield is an n+-type highly doped silicon substrate on which the oxide is disposed.

12. The strain gauge of claim 10 , wherein the conductive shield is a metal layer on which the oxide is disposed.

13. The strain gauge of claim 1 , wherein the isolation element includes a first isolation element disposed on a lower side of the resistor and a second isolation element disposed on an upper side of the resistor opposite the lower side.

14. The strain gauge of claim 13 , wherein the conductive shield includes a first conductive shield disposed on a side of the first isolation element opposite the resistor and a second conductive shield disposed on a side of the second isolation element opposite the resistor.

15. The strain gauge of claim 13 , further comprising a contact pad electrically connected to the resistor and extending through the second isolation element.

16. The strain gauge of claim 14 , further comprising a passivation layer positioned over the second conductive shield.

17. A strain measurement assembly, comprising:
a force responsive member;
a strain gauge including a resistor formed of a doped silicon material, a conductive shield, and an isolation element disposed between the resistor and the conductive shield and electrically isolating the resistor from the conductive shield, the isolation element includes a first isolation element disposed on a lower side of the resistor and a second isolation element disposed on an upper side of the resistor opposite the lower side, the conductive shield includes a first conductive shield disposed on a side of the first isolation element opposite the resistor and a second conductive shield disposed on a side of the second isolation element opposite the resistor; and
an attachment material attaching the strain gauge to the force responsive member.

18. A strain gauge, comprising:
a resistor formed of a doped silicon material;
a conductive shield;
an isolation element disposed between the resistor and the conductive shield and electrically isolating the resistor from the conductive shield, the isolation element includes a first isolation element disposed on a lower side of the resistor and a second isolation element disposed on an upper side of the resistor opposite the lower side; and
a contact pad electrically connected to the resistor and extending through the second isolation element.

Assignees

• Measurement Spec Inc
• Tyco Electronics Amp Korea Co Ltd
• Te Connectivity Solutions Gmbh

Inventors

• Wagner David Eric
• Hoffman James
• Young-Deok Kim

Classifications

• H10W42/20

  protecting against electromagnetic or particle radiation, e.g. light, X-rays, gamma-rays or electrons · CPC title

• G01L1/2293 Primary

  of the semi-conductor type · CPC title

• H10N30/302

  Sensors · CPC title

• G01B7/18 Primary

  using change in resistance · CPC title

• G01L1/2287 Primary

  constructional details of the strain gauges (adjustable resistors H01C10/00) · CPC title