Integrated micromechanical sensor device

• US 5,744,719 A
• Filed: 06/12/1996
• Issued: 04/28/1998
• Est. Priority Date: 09/21/1993
• Status: Expired due to Term

• Current Assignee: Infineon Technologies AG
• Original Assignee: Siemens AG
• Inventors: Werner, Wolfgang
• Primary Examiner(s): Dougherty, Elizabeth L.
• Assistant Examiner(s): Noori, Max H.
• Application Number:
  US08/619,735
• Time in Patent Office: 685 Days
• Field of Search: 73/514.01, 73/514.32, 73/514.34, 73/721, 73/718, 73/727
• US Class Current: 73/514.32
• CPC Class Codes: B81B 3/0013 Structures dimensioned for mechanical prevention of stiction, e.g. spring with increased stiffness
• CPC Class Codes: B81C 1/00928 Eliminating or avoiding remaining moisture after the wet etch release of the movable structure
• CPC Class Codes: B81C 2201/117 Using supercritical fluid, e.g. carbon dioxide, for removing sacrificial layers
• CPC Class Codes: G01P 15/0802 Details
• CPC Class Codes: G01P 2015/0814 for translational movement of the mass, e.g. shuttle type

Abstract

The integrated micromechanical sensor device contains a body with a substrate (1) on which an insulating layer (2) and thereon a monocrystalline silicon layer (3), are arranged, in which the silicon layer has trenches as far as the surface of the insulating layer, and the side walls of the trenches as well as the side of the silicon layer adjacent to the insulating layer have a first doping type (n⁺) and the silicon layer has a second doping type (n^-) at least in a partial region of its remaining surface, in which the silicon layer has a transistor arrangement in a first region (TB) and a sensor arrangement in a second region (SB), for which the insulating layer (2) is partly removed under the second region. Such a sensor device has considerable advantages over known devices with regard to its properties and its production process.

Claims

1. An integrated micromechanical sensor device, comprising:

a sensor body formed of a substrate, a monocrystalline silicon layer disposed on said substrate, and an insulating layer disposed in a predetermined region between said substrate and said silicon layer;

said silicon layer having trenches with side walls formed therein from an upper surface thereof to a lower boundary surface, and said silicon layer having a first region above said insulating layer and a second region at which said insulating layer is at least partly missing;

said side walls of said trenches and a side of said silicon layer carrying the lower boundary surface having a first predetermined doping type, and said silicon layer having a second predetermined doping type at least in a partial region thereof;

a transistor configuration disposed in said first region of said silicon layer; and

a sensor configuration disposed in said second region (SB) of said silicon layer.

2. The device according to claim 1, wherein said trenches formed in said first region are filled with an insulant.

3. The device according to claim 1, wherein said transistor congfiguration is one of a bipolar, MOS, and bipolar/MOS transistor configuration.

4. The device according to claim 1, including at least one spring, said sensor configuration being suspended from said at least one spring.

5. The device according to claim 1, wherein said sensor configuration is a capacitive sensor.

6. The device according to claim 1, wherein said sensor configuration is a piezoresistive sensor.