Semiconductor pressure transducer

Claim 2

A semiconductor pressure transducer comprising: a measuring diaphragm formed of semiconductor material; a support member formed of semiconductor material for supporting said measuring diaphragm; an oxide layer and a thin glass layer interposed between said measuring diaphragm and said support member; a main body on which said support member is mounted; and means located in said main body for applying pressures of fluids to be measured to said measuring diaphragm.

Claim 3

A semiconductor pressure transducer as claimed in claim 1, wherein said measuring diaphragm and said support member are joined to each other by anodic bonding through said thin glass layer.

Claim 4

A semiconductor pressure transducer as claimed in claim 1, wherein said oxide layer is located on said support member.

Claim 5

A semiconductor pressure transducer as claimed in claim 3, wherein said thin glass layer is located on said oxide layer.

Claim 6

A semiconductor pressure transducer as claimed in claim 4, wherein said thin glass layer is formed by sputtering.

Claim 7

A semiconductor pressure transducer as claimed in claim 4, wherein said thin glass layer has a thickness below 10 µm.

Claim 8

A semiconductor pressure transducer comprising: a pressure sensing section main body having introduced thereinto two fluids of different pressures to be measured; a measuring diaphragm of semiconductor material including a large thickness portion, a small thickness portion formed with piezo resistance elements located outside said large thickness portion and a fixed portion of large thickness located outside said small thickness portion; a support member of semiconductor material joined to said fixed portion of said measuring diaphragm through an oxide layer and a thin glass layer; pressure passageways for fluids formed in said support member; and means for applying pressures of said two fluids to be measured to opposite side surfaces of said measuring diaphragm.

Claim 9

A semiconductor pressure transducer comprising: a pressure sensing section main body having introduced thereinto two fluids of different pressures to be measured; a measuring diaphragm of semiconductor material including a large thickness portion, a small thickness portion formed with piezo resistance elements located outside said large thickness portion and a fixed portion of large thickness located outside said small thickness portion; a support member of semiconductor material joined to said fixed portion of said measuring diaphragm through an oxide layer and a thin glass layer; pressure passageways for fluids formed in said support member; and means for applying pressures of said two fluids to be measured to opposite side surfaces of said measuring diaphragm.

Claim 10

A semiconductor pressure transducer as claimed in claim 7, wherein the crystal surface of said measuring diaphragm is a {100} surface and said piezo resistance elements are arranged parallel to a <110> axis.

Claim 11

A semiconductor pressure transducer as claimed in claim 7, further comprising a support member of metal interposed between said support member and said main body.

Claim 12

A semiconductor pressure transducer as claimed in claim 10, wherein said support member of metal is formed of an alloy selected from the group consisting of an Fe-Ni alloy and an Fe-Ni-Co alloy.

Claim 13

A semiconductor pressure transducer comprising: a pressure receiving section main body; two seal diaphragms each located on either side of said pressure receiving section main body for defining a high pressure fluid receiving chamber and a low pressure fluid receiving chamber; a center diaphragm arranged in said pressure receiving section main body to define two separation chambers each communicating with one of said pressure receiving chambers; a measuring diaphragm of semiconductor material formed with piezo resistance elements on one surface thereof and formed with a large thickness central portion, a large thickness outer peripheral portion and a small thickness portion interposed between said central portion and said outer peripheral portion; a support member of semiconductor material having a pressure passageway connected at one end to a peripheral portion of said the other surface of said measuring diaphragm through a thin glass layer and an oxide layer; a support member of metal having a pressure passageway connected at one end to the other end of said support member of semiconductor material and communicated with said pressure passageway of said support member of semiconductor material; a pressure sensing section main body connected to the other end of said connecting member of metal; a connecting metal member having a first pressure passageway communicating said the other surface of said measuring diaphragm with one of said pressure receiving chambers through the support members of semiconductor material and metal, and a second pressure passageway communicating said one surface of said measuring diaphragm with the other pressure receiving chamber; and a noncompressive fluid sealed in said pressure receiving chambers, separation chambers and first and second pressure passagways.

Claim 14

A semiconductor pressure transducer comprising: a pressure receiving section main body; two seal diaphragms each located on either side of said pressure receiving section main body for defining a high pressure fluid receiving chamber and a low pressure fluid receiving chamber; a center diaphragm arranged in said pressure receiving section main body to define two separation chambers each communicating with one of said pressure receiving chambers; a measuring diaphragm of semiconductor material formed with piezo resistance elements on one surface thereof and formed with a large thickness central portion, a large thickness outer peripheral portion and a small thickness portion interposed between said central portion and said outer peripheral portion; a support member of semiconductor material having a pressure passageway connected at one end to a peripheral portion of said the other surface of said measuring diaphragm through a thin glass layer and an oxide layer; a support member of metal having a pressure passageway connected at one end to the other end of said support member of semiconductor material and communicated with said pressure passageway of said support member of semiconductor material; a pressure sensing section main body connected to the other end of said connecting member of metal; a connecting metal member having a first pressure passageway communicating said the other surface of said measuring diaphragm with one of said pressure receiving chambers through the support members of semiconductor material and metal, and a second pressure passageway communicating said one surface of said measuring diaphragm with the other pressure receiving chamber; and a noncompressive fluid sealed in said pressure receiving chambers, separation chambers and first and second pressure passagways.

Claim 15

A semiconductor pressure transducer comprising: a measuring diaphragm of semiconductor material; a support member of semiconductor material cooperating with said measuring diaphragm to define measuring chambers therebetween; an oxide layer and a thin glass layer interposed between said measuring diaphragm and support member; a main body having said support member mounted thereon; pressure passageways formed in said main body for leading fluids to be measured to said measuring chambers; and means for sensing changes in electrostatic capacity between said measuring diaphragm and said support member.

Claim 16

A semiconductor pressure transducer comprising: a measuring diaphragm of semiconductor material; a support member of semiconductor material cooperating with said measuring diaphragm to define measuring chambers therebetween; an oxide layer and a thin glass layer interposed between said measuring diaphragm and support member; a main body having said support member mounted thereon; pressure passageways formed in said main body for leading fluids to be measured to said measuring chambers; and means for sensing changes in electrostatic capacity between said measuring diaphragm and said support member.