Micromechanical semiconductor sensing device

• US 9,567,211 B2
• Filed: 04/15/2015
• Issued: 02/14/2017
• Est. Priority Date: 12/19/2011
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Kalz, Franz-Peter, Theuss, Horst, Winkler, Bernhard, Hosseini, Khalil, Mahler, Joachim, Mengel, Manfred
• Primary Examiner(s): Noori, Max
• Application Number:
  US14/687,835
• Publication Number:
  US 20150217994A1
• Time in Patent Office: 671 Days
• Field of Search: 737/60, 737/77
• US Class Current: 1/1
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2201/0264 Pressure sensors
• CPC Class Codes: B81B 3/0021 Transducers for transforming electrical into mechanical energy or vice versa dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00
• CPC Class Codes: B81B 3/0072 For controlling internal stress or strain in moving or flexible elements, e.g. stress compensating layers
• CPC Class Codes: B81B 7/02 containing distinct electrical or optical devices of particular relevance for their function, e.g. microelectro-mechanical systems [MEMS] B81B7/04 takes precedence
• CPC Class Codes: B81C 2203/0154 Moulding a cap over the MEMS device
• CPC Class Codes: G01L 1/18 using properties of piezo-resistive materials, i.e. materials of which the ohmic resistance varies according to changes in magnitude or direction of force applied to the material
• 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 9/0072 using variations in capacitance
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• 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 2924/1815 Shape
• CPC Class Codes: H01L 2924/3511 Warping

Abstract

Micromechanical semiconductor sensing device comprises a micromechanical sensing structure being configured to yield an electrical sensing signal, and a piezoresistive sensing device provided in the micromechanical sensing structure, said piezoresistive sensing device being arranged to sense a mechanical stress disturbing the electrical sensing signal and being configured to yield an electrical disturbance signal based on the sensed mechanical stress disturbing the electrical sensing signal.

Claims

1. A micromechanical semiconductor sensing device comprising:

a micromechanical sensing structure including a first piezoresistive sensing device responsive to an external force on the micromechanical semiconductor sensing device, the micromechanical sensing structure configured to output an electrical sensing signal responsive to the external force; and

a second piezoresistive sensing device embedded in the micromechanical sensing structure, the second piezoresistive sensing device configured to sense a mechanical stress in the micromechanical sensing structure due to the external force on the micromechanical semiconductor sensing device, and configured to output an electrical disturbance signal responsive to the sensed mechanical stress.

2. The micromechanical semiconductor sensing device according to claim 1, further comprising a compensation logic configured to compensate, based on the electrical disturbance signal, a disturbance in the electrical sensing signal caused by the mechanical stress.

3. The micromechanical semiconductor sensing device according to claim 1, wherein the micromechanical sensing structure comprises a capacitive pressure sensor, and wherein the first piezoresistive sensing device comprises a movable diaphragm above a hollow space.

4. The micromechanical semiconductor sensing device according to claim 1, wherein the micromechanical sensing structure comprises an acceleration sensing device, wherein the first piezoresistive sensing device comprises an inertial element inside a cavity, and wherein the cavity is supported by a support structure.

5. A method for manufacturing a micromechanical semiconductor sensing device, the method comprising:

structuring a micromechanical sensing structure to include a first piezoresistive sensing device responsive to an external force on the micromechanical semiconductor sensing device, the micromechanical sensing structure outputting an electrical sensing signal responsive to the external force; and

embedding at least one second piezoresistive sensing device in the micromechanical sensing structure for sensing a mechanical stress in the micromechanical sensing structure due to the external force on the micromechanical semiconductor sensing device, and for outputting an electrical disturbance signal responsive to the sensed mechanical stress.

6. The method according to claim 5, wherein the micromechanical sensing structure is structured as a capacitive pressure sensor, and wherein the first piezoresistive sensing device comprises a movable diaphragm above a hollow space.

7. The method according to claim 5, wherein the micromechanical sensing structure is structured as an acceleration sensing device, wherein the first piezoresistive sensing device comprises an inertial element inside a cavity, and wherein the cavity is supported by a support structure.