US 11,940,346 B2
Micromechanical pressure sensor device and a corresponding production method
Johannes Meckbach, Tuebingen (DE); and Thomas Friedrich, Moessingen-Oeschingen (DE)
Assigned to ROBERT BOSCH GMBH, Stuttgart (DE)
Appl. No. 17/291,244
Filed by Robert Bosch GmbH, Stuttgart (DE)
PCT Filed Dec. 13, 2019, PCT No. PCT/EP2019/085105
§ 371(c)(1), (2) Date May 4, 2021,
PCT Pub. No. WO2020/126915, PCT Pub. Date Jun. 25, 2020.
Claims priority of application No. 102018222738.1 (DE), filed on Dec. 21, 2018.
Prior Publication US 2021/0389202 A1, Dec. 16, 2021
Int. Cl. G01L 9/00 (2006.01); B81B 3/00 (2006.01)
CPC G01L 9/0073 (2013.01) [B81B 3/0078 (2013.01); B81B 2201/0264 (2013.01); B81B 2203/0127 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A micromechanical pressure sensor device, comprising:
a semiconductor base substrate of a first doping type, on which an intermediate layer of the first doping type is situated;
a cavity, which includes a recess of a subregion of the semiconductor base substrate and a recess of the intermediate layer;
a sealing layer, the cavity being sealed by a sealing layer of a second doping type and containing a reference pressure, the sealing layer having a diaphragm region situated on a topside of the cavity;
a first grating of the second doping type, which is suspended on a buried connection region of the second doping type, the buried connection region extending laterally away from the cavity into the semiconductor base substrate;
a second grating of the second doping type, which is situated on a side of the diaphragm region pointing to the cavity and is suspended on the diaphragm region, the first grating and the second grating being electrically insulated from each other and forming a capacitance;
a first connection electrically connected to the first grating via the buried connection region; and
a second connection electrically connected to the second grating;
wherein a pressure change between an external pressure and the reference pressure is able to be detected by a capacitance change between the first connection and the second connection.