Micromechanical pressure sensor device including a diaphragm system and corresponding manufacturing method

A micromechanical pressure sensor device, comprising:

• a sensor substrate;
• a diaphragm system that is anchored in the sensor substrate and that includes a first diaphragm and a second diaphragm situated spaced apart therefrom, which are circumferentially connected to one another in an edge area, and enclose a reference pressure in an interior space formed in between the first and second diaphragm;
• and
• a plate-shaped central electrode that is suspended in the interior space and that is situated spaced apart from the first diaphragm and from the second diaphragm and that forms a first capacitor with the first diaphragm and forms a second capacitor with the second diaphragm;
• wherein the first diaphragm and the second diaphragm are configured in such a way that they are deformable toward one another when acted on by an external pressure,
• wherein the diaphragm system is situated in a cantilever manner, and is anchored in the sensor substrate across at least one extension area that extends laterally away from the diaphragm system.

A method for manufacturing a micromechanical pressure sensor device, comprising the following steps:

• forming a diaphragm system that is anchored in a sensor substrate, and includes a first diaphragm and a second diaphragm situated spaced apart from one another and which are circumferentially connected to one another in an edge area and enclose a reference pressure in an interior space formed in between the first and second diaphragms;
• and
• forming a plate-shaped electrode central electrode that is suspended in the interior space and that is situated spaced apart from the first diaphragm and from the second diaphragm, and that forms a first capacitor with the first diaphragm and forms a second capacitor with the second diaphragm, the first diaphragm and the second diaphragm being formed in such a way that they are deformable toward one another when acted on by an external pressure,
• wherein the diaphragm system is situated in a cantilever manner.

A method for manufacturing a micromechanical pressure sensor device, comprising the following steps:

• forming a diaphragm system that is anchored in a sensor substrate, and includes a first diaphragm and a second diaphragm situated spaced apart from one another and which are circumferentially connected to one another in an edge area and enclose a reference pressure in an interior space formed in between the first and second diaphragms;
• and
• forming a plate-shaped electrode central electrode that is suspended in the interior space and that is situated spaced apart from the first diaphragm and from the second diaphragm, and that forms a first capacitor with the first and forms a second capacitor with the second diaphragm, the first diaphragm and the second diaphragm being formed in such a way that they are deformable toward one another when acted on by an external pressure,
• wherein the first diaphragm is formed from a first conductive layer that is deposited and structured above a base substrate, the central electrode being formed from a second conductive layer that is deposited and structured above the first conductive layer, and the second diaphragm being formed from third and fourth conductive layers that are deposited and structured above the second conductive layer.

A method for manufacturing a micromechanical pressure sensor device, comprising the following steps:

• forming a diaphragm system that is anchored in a sensor substrate, and includes a first diaphragm and a second diaphragm situated spaced apart from one another and which are circumferentially connected to one another in an edge area and enclose a reference pressure in an interior space formed in between the first and second diaphragms;
• and
• forming a plate-shaped electrode central electrode that is suspended in the interior space and that is situated spaced apart from the first diaphragm and from the second diaphragm, and that forms a first capacitor with the first and forms a second capacitor with the second diaphragm, the first diaphragm and the second diaphragm being formed in such a way that they are deformable toward one another when acted on by an external pressure,
• wherein a space is formed between the diaphragm system and an edge area of a surrounding sensor substrate, so that the diaphragm system is situated in a cantilever manner.