MEMS based sensors, particularly capacitive sensors, potentially can address critical considerations for users including accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, and cost effectiveness. Accordingly, it would be beneficial to exploit MEMS processes that allow for manufacturability and integration of resonator elements into cavities within the MEMS sensor that are at low pressure allowing high quality factor resonators and absolute pressure sensors to be implemented. Embodiments of the invention provide capacitive sensors and MEMS elements that can be implemented directly above silicon CMOS electronics.

MEMS based sensors, particularly capacitive sensors, potentially can address critical considerations for users including accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, and cost effectiveness. Accordingly, it would be beneficial to exploit MEMS processes that allow for manufacturability and integration of resonator elements into cavities within the MEMS sensor that are at low pressure allowing high quality factor resonators and absolute pressure sensors to be implemented. Embodiments of the invention provide capacitive sensors and MEMS elements that can be implemented directly above silicon CMOS electronics.

A method produces a micromechanical sensor element having a first electrode and a second electrode, wherein electrode wall surfaces of the first and the second electrodes are situated opposite one another in a first direction and form a capacitance, wherein one of the first electrode or the second electrode is movable in a second direction, in response to a variable to be detected, and a second one of the first electrode and the second electrode is fixed. The method includes producing a cavity in a semiconductor substrate, the cavity being closed by a doped semiconductor layer; producing the first and the second electrodes in the semiconductor layer, including modifying the electrode wall surface of the first electrode in order to have a smaller extent in the second direction than the electrode wall surface of the second electrode.

A method produces a micromechanical sensor element having a first electrode and a second electrode, wherein electrode wall surfaces of the first and the second electrodes are situated opposite one another in a first direction and form a capacitance, wherein one of the first electrode or the second electrode is movable in a second direction, in response to a variable to be detected, and a second one of the first electrode and the second electrode is fixed. The method includes producing a cavity in a semiconductor substrate, the cavity being closed by a doped semiconductor layer; producing the first and the second electrodes in the semiconductor layer, including modifying the electrode wall surface of the first electrode in order to have a smaller extent in the second direction than the electrode wall surface of the second electrode.

A pressure detection element includes a substrate, first and second electrodes on the substrate, a membrane including a first diaphragm portion and a second diaphragm portion and spaced from the substrate, and a spacer between the substrate and the membrane to define a first space in which the first electrode and the first diaphragm portion are spaced from and opposed to each other and a second space in which the second electrode and the second diaphragm portion are spaced from and opposed to each other. The substrate includes a trench in a portion positioned between the first diaphragm portion and the second diaphragm portion when viewed in a direction in which the substrate and the membrane are opposed.

A pressure detection element includes a substrate, first and second electrodes on the substrate, a membrane including a first diaphragm portion and a second diaphragm portion and spaced from the substrate, and a spacer between the substrate and the membrane to define a first space in which the first electrode and the first diaphragm portion are spaced from and opposed to each other and a second space in which the second electrode and the second diaphragm portion are spaced from and opposed to each other. The substrate includes a trench in a portion positioned between the first diaphragm portion and the second diaphragm portion when viewed in a direction in which the substrate and the membrane are opposed.

A pressure sensor comprises a polysilicon sensing membrane. The pressure sensor further includes one or more polysilicon electrodes disposed over a silicon substrate. The sensor also includes one or more polysilicon routing layers that electrically connects electrodes of the one or more polysilicon electrodes to one another, wherein the polysilicon sensing membrane deforms responsive to a stimuli and changes a capacitance between the polysilicon sensing membrane and the one or more polysilicon electrodes. The sensor also includes one or more vacuum cavities positioned between the polysilicon sensing membrane and the one or more polysilicon electrodes.

A pressure sensor comprises a polysilicon sensing membrane. The pressure sensor further includes one or more polysilicon electrodes disposed over a silicon substrate. The sensor also includes one or more polysilicon routing layers that electrically connects electrodes of the one or more polysilicon electrodes to one another, wherein the polysilicon sensing membrane deforms responsive to a stimuli and changes a capacitance between the polysilicon sensing membrane and the one or more polysilicon electrodes. The sensor also includes one or more vacuum cavities positioned between the polysilicon sensing membrane and the one or more polysilicon electrodes.

MEMS based sensors, particularly capacitive sensors, potentially can address critical considerations for users including accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, and cost effectiveness. Accordingly, it would be beneficial to exploit MEMS processes that allow for manufacturability and integration of resonator elements into cavities within the MEMS sensor that are at low pressure allowing high quality factor resonators and absolute pressure sensors to be implemented. Embodiments of the invention provide capacitive sensors and MEMS elements that can be implemented directly above silicon CMOS electronics.

MEMS based sensors, particularly capacitive sensors, potentially can address critical considerations for users including accuracy, repeatability, long-term stability, ease of calibration, resistance to chemical and physical contaminants, size, packaging, and cost effectiveness. Accordingly, it would be beneficial to exploit MEMS processes that allow for manufacturability and integration of resonator elements into cavities within the MEMS sensor that are at low pressure allowing high quality factor resonators and absolute pressure sensors to be implemented. Embodiments of the invention provide capacitive sensors and MEMS elements that can be implemented directly above silicon CMOS electronics.