The disclosure relates to a method for manufacturing recessed micromechanical structures in a MEMS device wafer. First vertical trenches in the device wafer define the horizontal dimensions of both level and recessed structures. The horizontal face of the device wafer and the vertical sidewalls of the first vertical trenches are then covered with a self-supporting etching mask which is made of a self-supporting mask material, which is sufficiently rigid to remain standing vertically in the location where it was deposited even as the sidewall upon which it was deposited is etched away. Recess trenches are then etched under the protection of the self-supporting mask. The method allows a spike-preventing aggressive etch to be used for forming the recess trenches, without harming the sidewalls in the first vertical trenches.

A micro-electromechanical system (MEMS) device includes a substrate and a beam suspended relative to a surface of the substrate. The substrate includes a buried insulator layer and a cavity. The beam includes a first portion and a second portion that are separated by an isolation joint. The cavity separates the surface of the substrate from the beam.

Disclosed herein are aspects of a multiple-mass, multi-axis microelectromechanical systems (MEMS) accelerometer sensor device with a fully differential sensing design that applies differential drive signals to movable proof masses and senses differential motion signals at sense fingers coupled to a substrate. In some embodiments, capacitance signals from different sense fingers are combined together at a sensing signal node disposed on the substrate supporting the proof masses. In some embodiments, a split shield may be provided, with a first shield underneath a proof mass coupled to the same drive signal applied to the proof mass and a second shield electrically isolated from the first shield provided underneath the sense fingers and biased with a constant voltage to provide shielding for the sense fingers.

A MEMS inertial sensor includes a supporting structure and an inertial structure. The inertial structure includes at least one inertial mass, an elastic structure, and a stopper structure. The elastic structure is mechanically coupled to the inertial mass and to the supporting structure so as to enable a movement of the inertial mass along a first direction, when the supporting structure is subjected to an acceleration parallel to the first direction. The stopper structure is fixed with respect to the supporting structure and includes at least one primary and one secondary stopper elements. If the acceleration exceeds a first threshold value, the inertial mass abuts against the primary stopper element and subsequently rotates about an axis of rotation defined by the primary stopper element. If the acceleration exceeds a second threshold value, rotation of the inertial mass terminates when the inertial mass abuts against the secondary stopper element.

A microelectromechanical device includes a substrate, a first structural layer, and a second structural layer of semiconductor material. A sensing mass extends in the first structural layer and is coupled to the substrate by first elastic connections to enable oscillation of the sensing mass in a sensing direction perpendicular to the substrate by a maximum amount relative to a resting position of the sensing mass. An out-of-plane stopper structure includes an anchorage fixed to the substrate and a mechanical end-of-travel structure, which extends in the second structural layer, faces the sensing mass, and is separated therefrom by a gap having a width smaller than the maximum displacement distance of the sensing mass. The mechanical end-of-travel structure is coupled to the anchorage by second elastic connections that enable movement of the mechanical end-of-travel structure in the sensing direction in response to an impact of the sensing mass.

A method includes forming an etch stop layer over a first side of a device wafer. The method also includes forming a polysilicon layer over the etch stop layer. A handle wafer is fusion bonded to the first side of the device wafer. A eutectic bond layer is formed on a second side of the device wafer. A micro-electro-mechanical system (MEMS) features are etched into the second side of the device wafer to expose the etch stop layer. The exposed etch stop layer is removed to expose the polysilicon layer. The exposed polysilicon layer is removed to expose a cavity formed between the handle wafer and the device wafer.

The present invention relates to a method and an apparatus for detecting a failure of a sensor device during operation of the sensor device. A test signal is generated in a first frequency band that is above a signal frequency band of the sensor device and fed into a sensor element of the sensor device. A set of samples is obtained, and a magnitude value is derived from said at least two consecutive samples at the first frequency band. The magnitude value is compared to a magnitude threshold value that defines a minimum for the magnitude value and if the magnitude value is below the magnitude threshold value, it is determined that an error has occurred in the sensor device.

A method of manufacturing a semiconductive structure includes receiving a first substrate; disposing an interconnection layer on the first substrate; forming a plurality of conductors over the interconnection layer; filing gaps between the plurality of conductors with a film; forming a barrier layer over the film; removing the barrier layer; and partially removing the film to expose a portion of the interconnection and leave a portion of the interconnection layer covered by the film.

A semiconductor device may include a first substrate, a first electrical component, a lid, a second substrate, and a second electrical component. The first substrate may include an upper surface, a lower surface, and an upper cavity in the upper surface. The first electrical component may reside in the upper cavity of the first substrate. The lid may cover the upper cavity and may include a port that permits fluid to flow between an environment external to the semiconductor device and the upper cavity. The second substrate may include the second electrical component mounted to an upper surface of the second substrate. The lower surface of the first substrate and the upper surface of the second substrate may fluidically seal the second electrical component from the upper cavity.

A method for manufacturing a MEMS structure is provided. The method includes providing a MEMS substrate having a first surface, forming a first buffer layer on the first surface of the MEMS substrate, and forming a first roughening layer on the first buffer layer. Also, a MEMS structure is provided. The MEMS structure includes a MEMS substrate, a first buffer layer, a first roughening layer, and a CMOS substrate. The MEMS substrate has a first surface and a pillar is on the first surface. The first buffer layer is on the first surface. The first roughening layer is on the first buffer layer. The CMOS substrate has a second surface and is bonded to the MEMS substrate via the pillar. Moreover, an air gap is between the first roughening layer and the second surface of the CMOS substrate.