Combined pressure and humidity sensor

• US 10,184,910 B2
• Filed: 10/25/2013
• Issued: 01/22/2019
• Est. Priority Date: 10/25/2012
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Lammel, Gerhard, Waffenschmidt, Sibylle, Feyh, Ando, O'Brien, Gary, Graham, Andrew
• Primary Examiner(s): Caputo, Lisa
• Assistant Examiner(s): Roberts, Herbert K
• Application Number:
  US14/062,886
• Publication Number:
  US 20140116122A1
• Time in Patent Office: 1,915 Days
• CPC Class Codes: G01D 3/0365 the undesired influence being measured using a separate sensor, which produces an influence related signal
• CPC Class Codes: G01L 19/0038 being part of the housing other details about the housing 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 19/141 Monolithic housings, e.g. molded or one-piece housings
• CPC Class Codes: G01L 19/143 Two part housings
• CPC Class Codes: G01L 19/147 Details about the mounting of the sensor to support or covering means
• CPC Class Codes: G01N 27/041 of a solid body
• CPC Class Codes: G01N 27/223 for determining moisture content, e.g. humidity rain detectors on vehicle windows B60S1/0825
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/32145 the bodies being stacked
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/73253 Bump and layer connectors
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/15174 in different layers of the multilayer substrate

Abstract

A sensor device package includes a pressure sensor and a humidity sensor mounted on the same substrate and in the same housing with light protection for the pressure sensor a media opening for gas exchange for the humidity sensor. Light protection and rapid response times are provided through strategic positioning of the media opening, strategic arrangement of the pressure sensor, humidity sensor, and the media opening, and/or the use of opaque materials.

Claims

1. A semiconductor package comprising:

a substrate having an upper surface and a lower surface;

a housing cover having a sidewall portion attached to the substrate and a ceiling portion extending over the upper surface of the substrate, the substrate and the housing cover forming a housing that surrounds and defines a single shared, undivided interior volume;

a pressure sensor device mounted onto the substrate within the interior volume, the pressure sensor having a top side including a flexible membrane suspended over a hollow space;

a humidity sensor device mounted onto the substrate within the interior volume with the pressure sensor and including a moisture-sensitive material;

an evaluation circuit device mounted onto the substrate within the interior volume with the pressure sensor and the humidity sensor and electrically connected to the pressure sensor and the humidity sensor;

a media opening in the housing that enables gas exchange between the interior volume and an exterior of the housing,

wherein the housing cover is spaced apart from each of the pressure sensor, the humidity sensor and the evaluation circuit such that an open space is formed within the interior volume between the housing cover and each of the pressure sensor, the humidity sensor and the evaluation circuit, the media opening being in communication with the open space such that atmospheric conditions within the open space correspond to atmospheric conditions outside of the housing cover,

wherein the flexible membrane is arranged facing the ceiling portion of the housing cover with the hollow space positioned on an opposite side of the flexible membrane from the ceiling portion such that the flexible membrane is exposed directly to the open space of the interior volume,

wherein the media opening is positioned closer to the moisture-sensitive material of the humidity sensor than the flexible membrane of the pressure sensor, and

wherein the media opening is positioned in the housing at a location that is offset laterally from the pressure sensor device and closer to the upper surface than the top side of the pressure sensor device.

2. The package of claim 1, wherein the media opening extends through the sidewall portion of the housing cover,

wherein the top side of the pressure sensor is spaced farther apart from the substrate than an upper extent of the media opening in the sidewall.

3. The package of claim 2, wherein a lower extent of the media opening in the sidewall is spaced farther apart from the substrate than a lower surface of the evaluation circuit.

4. The package of claim 3, wherein the pressure sensor is provided on a first chip and the evaluation circuit is provided on a second chip, and

wherein the first chip is mounted onto the second chip.

5. The package of claim 4, wherein the second chip is electrically connected to the substrate using flip-chip technology.

6. The package of claim 5, wherein the humidity sensor is provided on a third chip, the third chip being mounted to the substrate alongside the first and the second chips, and

wherein the third chip is positioned proximate the media opening and the first and second chips are positioned farther away from the media opening than the third chip.

7. The package of claim 5, wherein the humidity sensor is integrated onto the first chip with the pressure sensor, the humidity sensor being laterally offset from the pressure sensor in the first chip, and

wherein the first chip is positioned with the humidity sensor oriented toward the media opening and the pressure sensor oriented away from the media opening.

8. The package of claim 1, wherein the media opening extends through the substrate directly beneath the humidity sensor device.

9. The package of claim 8, wherein the pressure sensor is provided on a first chip and the evaluation circuit is provided on a second chip, the first chip being mounted on top of the second chip, the second chip being mounted to the substrate,

wherein the humidity sensor is provided on a third chip, the third chip being mounted to the substrate alongside the first and the second chips, and

wherein the humidity sensor is oriented with the moisture-sensitive material facing toward the substrate and positioned above the media opening.

10. The package of claim 9, wherein the third chip is mounted to the substrate using flip-chip technology.