Sensor and method for manufacturing a sensor

• US 5,756,901 A
• Filed: 09/24/1996
• Issued: 05/26/1998
• Est. Priority Date: 10/11/1995
• Status: Expired due to Term

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Funk, Karsten, Laermer, Franz, Kurle, Juergen, Schilp, Andrea, Offenberg, Michael
• Primary Examiner(s): Williams, Hezron E.
• Assistant Examiner(s): MOLLER, RICHARD ALAN
• Application Number:
  US08/718,603
• Time in Patent Office: 609 Days
• Field of Search: 73/777, 73/780, 73/514.01, 73/514.32, 73/514.16, 73/514.21, 73/514.35, 73/514.36, 361/280, 361/283.1, 361/283.2, 361/283.3, 437/901, 437/921, 437/978, 437/979, 437/78, 437/225, 437/235, 437/238, 437/240, 257/417, 257/418, 257/415
• US Class Current: 73/777
• CPC Class Codes: B81B 2201/0235 Accelerometers
• CPC Class Codes: B81B 2203/033 Trenches
• CPC Class Codes: B81B 7/007 Interconnections between the MEMS and external electrical signals
• CPC Class Codes: B81C 1/0019 Flexible or deformable structures not provided for in groups B81C1/00142 - B81C1/00182
• CPC Class Codes: B81C 2201/0136 by doping limited material regions
• CPC Class Codes: B81C 2203/0118 Bonding a wafer on the substrate, i.e. where the cap consists of another wafer
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 15/125 by capacitive pick-up
• CPC Class Codes: G01P 2015/0814 for translational movement of the mass, e.g. shuttle type

Abstract

In a sensor and a method for manufacturing a sensor, a movable element is patterned out of a silicon layer and is secured to a substrate. The conducting layer is subdivided into various regions, which are electrically insulated from one another. The electrical connection between the various regions of the silicon layer is established by a conducting layer, which is arranged between a first and a second insulating layer.

Claims

1. A sensor comprising:

a substrate;

a silicon layer;

a movable element patterned out of the silicon layer, the movable element being joined to the substrate;

a conducting layer arranged between the substrate and the silicon layer, wherein a plurality of conductive paths patterned out of the conducting layer, electrically contact the movable element; and

an insulating layer for insulating the plurality of conductive paths from sections of the silicon layer.

2. The sensor according to claim 1, wherein the sensor measures an acceleration.

3. The sensor according to claim 1, wherein the substrate includes silicon.

4. The sensor according to claim 1, further comprising:

a further insulating layer arranged between the conducting layer and the substrate.

5. The sensor according to claim 1, further comprising:

a frame surrounding the movable element; and

a plurality of contact regions connected to the conductive paths and arranged outside of the frame.

6. The sensor according to claim 5, further comprising a cover connected to the frame, the movable element being contained in a cavity formed by the cover, the frame, and the substrate.

7. The sensor according to claim 1, further comprising a plurality of movable electrodes, a plurality of fixed electrodes and a plurality of connection structures, and wherein:

the movable element has a seismic mass;

the movable electrodes are suspended on the seismic mass;

the seismic mass and the movable electrodes become deformed in response to an acceleration parallel to the substrate;

the movable electrodes are connected through the conductive paths;

the fixed electrodes are connected by the connecting structures; and

the connecting structures are patterned out of the silicon layer.

8. The sensor according to claim 7, further comprising a plurality of contact regions, and wherein;

the fixed electrodes include a first group of fixed electrodes and a second group of fixed electrodes;

a distance between the movable electrodes and the first group of fixed electrodes is decreased when a distance between the movable electrodes and the second group of fixed electrodes increases; and

the first and second groups of fixed electrodes are connected to the contact regions through the conductive paths and the connecting structures.