Multi-function differential pressure sensor with thin supporting base

• US 5,635,649 A
• Filed: 05/23/1995
• Issued: 06/03/1997
• Est. Priority Date: 04/22/1991
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Aoki, Ken'ichi, Yamamoto, Yoshimi, Tobita, Tomoyuki, Nagasu, Akira
• Primary Examiner(s): Chilcot, Richard
• Assistant Examiner(s): FELBER, JOSEPH LEON
• Application Number:
  US08/447,705
• Time in Patent Office: 742 Days
• Field of Search: 73/708, 73/716, 73/717, 73/720, 73/721, 73/726, 73/727, 73/756, 338/4, 338/42
• US Class Current: 73/717
• CPC Class Codes: G01L 19/0084 to the outside of the housing other details about the housing see G01L19/14
• CPC Class Codes: G01L 19/0092 Pressure sensor associated with other sensors, e.g. for measuring acceleration or temperature G01L9/025, G01L9/045, G01L9/065, G01L9/085, G01L9/105, G01L9/125, G01L19/02, G01L19/04 take precedence; measuring two or more variable G01D21/02; temperature sensors with pressure compensation G01K1/26
• CPC Class Codes: G01L 19/02 Arrangements for preventing, or for compensating for, effects of inclination or acceleration of the measuring device; Zero-setting means for aneroid barometers G01L7/14
• CPC Class Codes: G01L 19/04 Means for compensating for effects of changes of temperature , i.e. other than electric compensation
• CPC Class Codes: G01L 19/146 using flexible element between the transducer and the support
• CPC Class Codes: G01L 19/147 Details about the mounting of the sensor to support or covering means

Abstract

A multi-function differential pressure sensor includes a semiconductor chip, a stationary base having a joining portion joined to a thick wall portion of the semiconductor chip, and a housing joined to the stationary base. The semiconductor chip is provided with a differential pressure detection unit, a static pressure detection unit, and a temperature detection unit. The joining portion of the stationary base is not thicker than the semiconductor chip. The stationary base has one or more thin wall portions located, in a plan view, within a circular pressure sensitive diaphragm of the semiconductor chip.

Claims

1. A multi-function differential pressure sensor comprising:

a single semiconductor chip including a thin wall portion, said thin wall portion having a differential pressure detection means mounted thereon for detecting a differential pressure, and a thick wall portion formed around said thin wall portion, said thick wall portion having a static pressure detection means mounted thereon for detecting a static pressure;

a stationary base having a joining base portion where said stationary base is joined to said semiconductor chip, said joining base portion being larger in area than said thick wall portion of said semiconductor chip and smaller in thickness than said thick wall portion of said semiconductor chip, and a thin wall portion arranged within said thin wall portion of said semiconductor chip as viewed in a plan view; and

a housing joined to said stationary base.

2. The sensor according to claim 1, further comprising a means arranged on said thick wall portion of said semiconductor chip for detecting a temperature.

3. The sensor according to claim 1, wherein said stationary base is made of a ceramic with a first joining layer formed on said joining surface to said semiconductor chip, which first joining layer is made of a solder selected from an oxide solder, a thin metallic film solder of Au and a thin metallic film solder of an Au-Si alloy, and is fixedly joined to said housing through a second joining layer which is formed on a portion of said stationary base to be joined to said housing and is made of one of the above solders, an inorganic binder and an organic binder.

4. The sensor according to claim 1, wherein said stationary base is made of a Fe-Ni alloy with a joining layer formed on a joining surface of said semiconductor chip, which layer is made of an oxide solder of a high dielectric strength, and is fixedly joined to said housing by welding.

5. The sensor according to claim 1, wherein said stationary base is made of a borosilicate glass, is joined to said semiconductor chip by means of an anodic oxide joining process, and is fixedly joined to said housing through a joining layer which is formed on a portion of said stationary base to be joined to said housing and is made of one of an oxide solder, a metallic solder, an inorganic binder and an organic binder.

6. The sensor according to claim 1, wherein said stationary base is made of a silicon with a layer formed on said joining surface to said semiconductor chip, which layer is made of either one of a low melting point glass and an oxide to serve as a solder layer for electrical insulation and joining, and is fixedly joined to said housing through another joining layer which is formed on a portion of said stationary base to be joined to said housing and is made of one of an oxide solder, a metallic solder, an inorganic binder and an organic binder.

7. The sensor according to claim 1, wherein the semiconductor chip has opposite pressure receiving surfaces.

8. A multi-function differential pressure sensor comprising:

a semiconductor chip of a single chip substrate including a thick wail portion, said substrate having thereon a differential pressure detection means for detecting a differential pressure, a temperature detection means for detecting a temperature and a static pressure detection means for detecting a static pressure, said differential pressure detection means including a pressure sensitive diaphragm;

a first stationary base having a joining base portion joined to said thick wail portion of said semiconductor chip and being equal to or less in thickness than said thick wall portion of said semiconductor chip, said joining base portion being larger in area than said thick wall portion of said semiconductor chip;

a second stationary base of a thin wail structure having an outer periphery arranged within a recess formed in said semiconductor chip for defining said pressure sensitive diaphragm of said differential pressure detection means as viewed in a plan view and a surface joined to said first stationary base; and

a housing having a means for taking out signals of said semiconductor chip, said housing being joined to another surface of said second stationary base.

9. The sensor according to claim 8, wherein said first stationary base is made of a borosilicate glass, said second stationary base is made of either one material of a Fe-Ni alloy and a Fe alloy, said semiconductor chip and said first stationary base are joined to each other by means of an anodic oxide joining process, and said first and second stationary bases are joined to each other by means of one of the anodic oxide joining process, an oxide solder, an inorganic binder, an organic binder and a metallic solder.

10. The sensor according to claim 8, wherein said first stationary base is made of either one material of a ceramic and a borosilicate glass, said second stationary base is made of one material selected from a ceramic, a borosilicate glass, a Fe-Ni alloy and another metallic material, said semiconductor chip and said first stationary base are joined to each other by means of one of an oxide solder, a metallic film solder of an Au-Si alloy, a metallic film solder of Au, another metallic solder, an anodic oxide joining process, an inorganic binder and an organic binder, and said first and said second stationary bases are joined to each other by means of one of the oxide solder, the metallic film solder of the Au-Si alloy, the metallic film solder of Au, another metallic solder, the anodic oxide joining process, the inorganic binder and the organic binder.

11. The sensor according to claim 8, wherein the semiconductor chip has opposite pressure receiving surfaces.

12. A multi-function differential pressure sensor comprising:

a semiconductor chip of a single chip substrate including a thick wall portion, said substrate having thereon a differential pressure detection means for detecting a differential pressure, a temperature detection means for detecting a temperature and a static pressure detection means for detection a static pressure, said differential pressure detection means including a pressure sensitive diaphragm;

a stationary base having a joining base portion joined to said semiconductor chip and being equal to or less in thickness than, said thick wall portion of said semiconductor chip, said joining base portion being larger in area than said thick wall portion of said semiconductor chip; and

a housing including a means for taking out output signals of said semiconductor chip and a joining portion of a thin wall structure joined to said stationary base, said joining portion having an outer periphery arranged within a recess formed in said semiconductor chip for defining said pressure sensitive diaphragm of said differential pressure detection means as viewed in a plan view.

13. The sensor according to claim 12, wherein said stationary base is made of a ceramic with a joining layer formed on said joining surface to said semiconductor chip, said joining layer being made of one of an oxide solder, a metallic solder of an Au film, a metallic solder of an Au-Si alloy film and another metallic solder, and is fixedly joined to said joining portion of the thin wall structure of said housing through one of the above layer, an inorganic binder and an organic binder.

14. The sensor according to claim 12, wherein said stationary base is made of a borosilicate glass, is joined to said semiconductor chip by an anodic oxide joining process and is fixedly joined to said joining portion of the thin wall structure of said housing through a layer made of one of an oxide solder, a metallic solder, an inorganic binder and an organic binder.

15. The sensor according to claim 12, wherein the semiconductor chip has opposite pressure receiving surfaces.