Disclosed are pressure sensors including a die and an application-specific integrated circuit (ASIC) mounted on a top surface of a substrate. The pressure sensor can define an inner volume and a bottom opening configured to abut the substrate. The die and ASIC are mounted on the top surface of the substrate within the inner volume. The substrate defines a first aperture therethrough and the die defines a second aperture therethrough in a direction along an axis perpendicular to the substrate, the first aperture and the second aperture being aligned. Metallic barrier(s) disposed on a bottom surface of the substrate, circumferentially about the first aperture, can be at least partially coated with solder mask to reduce or prevent flow of unwanted materials past the metallic barriers and through the first aperture. The substrate can include electrical connection pads on the bottom surface configured to be in communication with a daughter board.

To provide a pressure sensor element and a pressure sensor that have stable pressure sensitivity without the need for improving the accuracy of alignment between a diaphragm and a holding member, a pressure sensor element includes a thin plate diaphragm, a holding member that holds the diaphragm, and one or more strain resistance gauges that are provided on a first surface of the diaphragm and which change in resistance values according to deformation of the diaphragm, in which the holding member has recesses that, formed on an annular first end surface facing the first surface of the diaphragm, cut out parts of an inner circumference of the first end surface, and the strain resistance gauges are disposed near the regions corresponding to the recesses on the first surface of the diaphragm.

A capacitive sensor is disclosed. In an embodiment a semiconductor device includes a die including a capacitive pressure sensor integrated on a CMOS circuit, wherein the capacitive pressure sensor includes a first electrode and a second electrode separated from one another by a cavity, the second electrode including a suspended tensile membrane, and wherein the first electrode is composed of one or more aluminum-free layers containing Ti.

A pressure sensor device for a pressure sensor, in particular a capacitive pressure sensor, having a pressure chamber bounded by a movable sensing membrane and a stationary counterelectrode of the pressure sensor device. The sensing membrane and the counterelectrode each run in the longitudinal direction and the transverse direction of the pressure sensor device. The sensing membrane is directly or indirectly spring-mounted, in particular spring-mounted in two-dimensional fashion, in the pressure chamber relative to the counterelectrode by at least one micromechanical spring element, in particular a plurality of micromechanical spring elements.

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 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 includes a detection element that detects a change in pressure, and a cover member that accommodates the detection element and that includes a first through hole and a second through hole. Each of the first through hole and the second through hole is provided at a position that does not overlap the detection element in a front view of the respective hole.

A pressure sensing element, including a substrate, a device layer coupled to the substrate, a diaphragm being part of the device layer, and a plurality of piezoresistors coupled to the diaphragm. A plurality of bond pads is disposed on the device layer, and an electrical field shield is bonded to the top of device layer and at least one of the bond pads. At least one stress adjustor is part of the electrical field shield, where the stress adjustor is a cut-out constructed and arranged to reduce thermal hysteresis of the pressure sensing element caused by stress relaxation of the electrical field shield during a cooling and heating cycle. The stress adjustor may be a thin film deposited on top of the electrical field shield, which may apply residual stress to the piezoresistors. The pressure sensing element may include a cavity integrally formed as part of the substrate.

Disclosed are pressure sensors including a die and an application-specific integrated circuit (ASIC) mounted on a top surface of a substrate. The pressure sensor can define an inner volume and a bottom opening configured to abut the substrate. The die and ASIC are mounted on the top surface of the substrate within the inner volume. The substrate defines a first aperture therethrough and the die defines a second aperture therethrough in a direction along an axis perpendicular to the substrate, the first aperture and the second aperture being aligned. Metallic barrier(s) disposed on a bottom surface of the substrate, circumferentially about the first aperture, can be at least partially coated with solder mask to reduce or prevent flow of unwanted materials past the metallic barriers and through the first aperture. The substrate can include electrical connection pads on the bottom surface configured to be in communication with a daughter board.

A method includes depositing a passivation layer on a substrate; depositing and patterning a first polysilicon layer on the passivation layer; depositing and patterning a first oxide layer on the first polysilicon layer forming a patterned first oxide layer; depositing and patterning a second polysilicon layer on the patterned first oxide layer. A portion of the second polysilicon layer directly contacts a portion of the first polysilicon layer. A portion of the patterned second polysilicon layer corresponds to a bottom electrode. A second oxide layer is deposited on the patterned second polysilicon layer and on an exposed portion of the patterned first oxide layer. A portion of the second oxide layer corresponding to a sensing cavity is etched, exposing the bottom electrode. Another substrate is bonded to the second oxide layer enclosing the sensing cavity. A top electrode is disposed within the another substrate and positioned over the bottom electrode.