Pressure sensor chip

Patent metadata

Field	Value
Publication number	US-10401248-B2
Application number	US-201515300533-A
Country	US
Kind code	B2
Filing date	Mar 9, 2015
Priority date	Mar 31, 2014
Publication date	Sep 3, 2019
Grant date	Sep 3, 2019

Abstract

A pressure sensor chip according to the present invention includes a non-bonding region that is provided in a stopper member and connected to a periphery of a pressure introduction hole. A plurality of protrusions are discretely formed on at least one of a first surface and a second surface that face each other in the non-bonding region. Passages between the protrusions serve as channels between the periphery of the pressure introduction hole and a peripheral edge of the non-bonding region. Accordingly, stress concentration does not occur at a diaphragm edge and the expected withstand pressure can be obtained.

First claim

The invention claimed is:

1. A pressure sensor chip, comprising:
a sensor diaphragm that outputs a signal corresponding to a difference between pressures applied to one surface and an other surface of the sensor diaphragm; and
a first holding member and a second holding member that are respectively bonded to the one surface and the other surface of the sensor diaphragm in such a manner that peripheral portions of the first and second holding members face the one surface and the other surface of the sensor diaphragm, each of the first and second holding members including a pressure introduction hole that transmits a measurement pressure to the sensor diaphragm,
wherein the first holding member includes
a non-bonding region formed inside the first holding member, the non-bonding region being parallel to pressure-receiving surfaces of the sensor diaphragm and being connected to a periphery of the pressure introduction hole, and
a plurality of protrusions that are discretely formed on at least one of a first surface and a second surface that face each other in the non-bonding region inside the first holding member,

wherein passages between the plurality of protrusions formed in the first holding member form channels, the channels being formed at the periphery of the pressure introduction hole and extending to a peripheral edge of the non-bonding region, and at least one of the passages connects to the pressure introduction hole, and
wherein the second holding member includes
a recess formed in a surface of the second holding member at a side at which the second holding member is bonded to the other surface of the sensor diaphragm.

2. The pressure sensor chip according to claim 1 , wherein the first holding member further includes an annular groove formed in the first holding member at a peripheral portion of the non-bonding region so as to be recessed in a thickness direction of the first holding member.

3. The pressure sensor chip according to claim 2 ,
wherein a cross section of the annular groove along a plane perpendicular to a direction in which the annular groove extends has an arc shape.

4. The pressure sensor chip according to claim 1 ,
wherein the first holding member is divided into two portions by a plane that is parallel to the pressure-receiving surfaces of the sensor diaphragm and along which the non-bonding region is provided, and
wherein the two portions of the first holding member are bonded to each other in a region other than the first surface and the second surface that defines the non-bonding region.

5. The pressure sensor chip according to claim 1 ,
wherein the one surface of the sensor diaphragm is a pressure-receiving surface that receives a high-pressure-side measurement pressure, and
wherein the other surface of the sensor diaphragm is a pressure-receiving surface that receives a low-pressure-side measurement pressure.

6. The pressure sensor chip according to claim 1 ,
wherein the first holding member includes
a recess formed in a surface of the first holding member at a side at which the first holding member is bonded to the one surface of the sensor diaphragm,

wherein the second holding member includes
a non-bonding region formed inside the second holding member, the non-bonding region being parallel to the pressure-receiving surfaces of the sensor diaphragm and being connected to a periphery of the pressure introduction hole, and
a plurality of protrusions that are discretely formed on at least one of a first surface and a second surface that face each other in the non-bonding region in the second holding member, and

wherein passages between the plurality of protrusions formed in the second holding member form channels between the periphery of the pressure introduction hole and a peripheral edge of the non-bonding region.

7. The pressure sensor chip of claim 1 , wherein each of the plurality of protrusions is a circular column extending from the first surface to the second surface inside the first holding member.

8. The pressure sensor chip of claim 1 , wherein each of the plurality of protrusions is a hexagonal column.

9. A pressure sensor chip, comprising:
a sensor diaphragm that outputs a signal corresponding to a difference between pressures applied to one surface and an other surface of the sensor diaphragm; and
a first holding member and a second holding member that are respectively bonded to the one surface and the other surface of the sensor diaphragm in such a manner that peripheral portions of the first and second holding members face the one surface and the other surface of the sensor diaphragm, each of the first and second holding members including a pressure introduction hole that transmits a measurement pressure to the sensor diaphragm,
wherein the first holding member includes
a non-bonding region formed inside the first holding member, the non-bonding region being parallel to pressure-receiving surfaces of the sensor diaphragm and being connected to a periphery of the pressure introduction hole, and
a plurality of protrusions that are discretely formed on at least one of a first surface and a second surface that face each other in the non-bonding region inside the first holding member,

wherein passages between the plurality of protrusions formed in the first holding member form channels, the channels being formed at the periphery of the pressure introduction hole and extending to a peripheral edge of the non-bonding region,
wherein the second holding member includes a recess formed in a surface of the second holding member at a side at which the second holding member is bonded to the other surface of the sensor diaphragm, and
wherein the first holding member is configured to divide into two portions that are separated along the non-binding region, when the difference between the pressures exceeds a threshold.

10. A pressure sensor chip, comprising:
a sensor diaphragm that outputs a signal corresponding to a difference between pressures applied to one surface and an other surface of the sensor diaphragm; and
a first holding member and a second holding member that are respectively bonded to the one surface and the other surface of the sensor diaphragm in such a manner that peripheral portions of the first and second holding members face the one surface and the other surface of the sensor diaphragm, each of the first and second holding members including a pressure introduction hole that transmits a measurement pressure to the sensor diaphragm,
wherein the first holding member includes
a non-bonding region formed inside the first holding member, the non-bonding region being parallel to pressure-receiving surfaces of the sensor diaphragm and being connected to a periphery of the pressure introduction hole, and
a plurality of protrusions that are discretely formed on at least one of a first surface and a second surface that face each other in the non-bonding region inside the first holding member,

wherein passages between the plurality of protrusions foiled in the first holding member form channels, the channels being formed at the periphery of the pressure introduction hole and extending to a peripheral edge of the non-bonding region,
wherein the second holding member includes a recess formed in a surface of the second holding member at a side at which the second holding member is bonded to the other surface of the sensor diaphragm, and
wherein each of the plurality of protrusions is a circular column.

Assignees

• Azbil Corp

Inventors

• Tokuda Tomohisa
• Ishikura Yoshiyuki

Classifications

• G01L19/0618

  Overload protection · CPC title

• G01L13/02

  using elastically-deformable members or pistons as sensing elements · CPC title

• G01L9/0073

  using a semiconductive diaphragm · CPC title

• G01L9/0054

  integral with a semiconducting diaphragm · CPC title

• G01L9/0072

  using variations in capacitance · CPC title