Patent ID: 11940345
Assignee: ROBERT BOSCH GMBH
Field: Measurement (Instruments)
Classification: CPC G  B | IPC B  G

Claim 12:
13. A capacitive pressure sensor device comprising:
evaluation electronics; and
a micromechanical component for a capacitive pressure sensor device, the micromechanical component including:
a substrate;
a frame structure that frames a partial surface of the substrate and/or of at least one intermediate layer on the substrate;
a membrane that is tensioned by the frame structure in such a way that a self-supporting region of the membrane extends over the framed partial surface, with an internal volume between the membrane and the framed partial surface;
at least one first connector protruding from a radially interior region of the membrane towards the framed partial surface;
a measurement electrode that is situated on the framed partial surface;
a reference measurement electrode that is situated on the framed partial surface and is electrically insulated from the measurement electrode;
a counter-electrode arranged in the internal volume and attached to the membrane via the at least one first connector;
a reference counter-electrode; and
a second connector protruding from a radially exterior region of the membrane towards the substrate;
wherein:
the internal volume is enclosed by the frame structure and is air-tightly sealed with a reference pressure therein;
the self-supporting region of the membrane is deformable by a physical pressure that is applied on an external side of the self-supporting region, oriented away from the internal volume, when the physical pressure is unequal to the reference pressure;
the measurement electrode and the counter-electrode are capable of being electrically contacted for tapping a measurement voltage between the measurement electrode and the counter-electrode;
the reference measurement electrode and the reference counter-electrode are capable of being electrically contacted for tapping a reference voltage between the reference measurement electrode and of the reference counter-electrode;
the evaluation electronics is configured to:
determine, based on the tapped measurement voltage and the tapped reference voltage, a measurement value relating to the physical pressure prevailing on the external side of the self-supporting region; and
output the determined measurement value;

the reference counter-electrode is connected to the membrane by attachment of a radially exterior half of the reference counter-electrode to the second connector; and
a radially interior half of the reference counter-electrode is free from the membrane.