A preclean process may be omitted from a eutectic bonding sequence. To remove oxide from one or more surfaces of a device wafer of a micro-electromechanical-system (MEMS) structure, a duration of an acid-based etch process in the eutectic bonding sequence may be increased relative to the duration of the acid-based etch process when the preclean process is performed. The increased duration of the acid-based etch process enables the acid-based etch process to remove the oxide from the one or more surfaces of the device wafer without the use of a preceding preclean process. This reduces the complexity and cycle time of the eutectic bonding sequence, reduces the risk of stiction between suspended mechanical components of the MEMS structure, and/or reduces the likelihood that the MEMS structure may be rendered defective or inoperable during manufacturing, which increases process yield.

A preclean process may be omitted from a eutectic bonding sequence. To remove oxide from one or more surfaces of a device wafer of a micro-electromechanical-system (MEMS) structure, a duration of an acid-based etch process in the eutectic bonding sequence may be increased relative to the duration of the acid-based etch process when the preclean process is performed. The increased duration of the acid-based etch process enables the acid-based etch process to remove the oxide from the one or more surfaces of the device wafer without the use of a preceding preclean process. This reduces the complexity and cycle time of the eutectic bonding sequence, reduces the risk of stiction between suspended mechanical components of the MEMS structure, and/or reduces the likelihood that the MEMS structure may be rendered defective or inoperable during manufacturing, which increases process yield.

The present disclosure describes techniques for altering the epoxy wettability of a surface of a MEMS device. Particularly applicable to flip-chip bonding arrangements in which a top surface of a MEMS device is adhered to a package substrate. A barrier region is provided on a top surface of the MEMs device, laterally outside a region which forms, or overlies, the backplate and/or the cavity in the transducer substrate. The barrier region comprises a plurality of discontinuities, e.g. dimples, which inhibit the flow of epoxy.

In an embodiment a sensor arrangement includes a substrate, at least one spacer arranged directly onto a surface of the substrate, wherein the spacer comprises a soft material and a sensor chip attached to the substrate by an adhesive, wherein both the at least one spacer and the adhesive are arranged at least partly between the sensor chip and the substrate, and wherein the spacer is adapted and arranged to define a bond line thickness of the adhesive.

A compound sensor device includes a semiconductor substrate having an active electronic circuit formed in or on the semiconductor substrate. A sensor including a sensor substrate including a sensor circuit having an environmental sensor or actuator formed in or on the sensor substrate is micro-transfer printed onto the semiconductor substrate. One or more electrical conductors electrically connect the active electronic circuit to the sensor circuit. The semiconductor substrate includes a first material and the sensor substrate includes a second material different from the first material.

A microstructure may be provided by forming a metal layer such as a molybdenum layer over a substrate. An aluminum nitride layer is formed on a top surface of the metal layer. A surface portion of the aluminum nitride layer is converted into a continuous aluminum oxide-containing layer by oxidation. A dielectric spacer layer may be formed over the continuous aluminum oxide-containing layer. Contact via cavities extending through the dielectric spacer layer, the continuous aluminum oxide-containing layer, and the aluminum nitride layer and down to a respective portion of the at least one metal layer may be formed using etch processes that contain a wet etch step while suppressing formation of an undercut in the aluminum nitride layer. Contact via structures may be formed in the contact via cavities. The microstructure may include a micro-electromechanical system (MEMS) device containing a piezoelectric transducer.

A semiconductor device structure is provided. The semiconductor device structure includes a first wafer comprising a first face and a second face opposite the first face and having a plurality of predetermined die areas. A plurality of recesses are disposed in the first face of the first wafer. A first recess of the plurality of recesses extends in a direction substantially parallel to a first edge of at least one of the plurality of predetermined die areas and laterally surrounds the at least one of the plurality of predetermined die areas. A second wafer is bonded to the second face of the first wafer.

The present invention features a stretchable strain sensor for detecting minute amounts of strain or pressure. The stretchable strain sensor may comprise a first soft polymer layer, a wrinkled conductive layer disposed on the first soft polymer layer, and a second soft polymer layer disposed on the wrinkled conductive layer. Strain applied to the sensor may cause the wrinkled conductive layer to stretch and crack and send a signal based on resistance. Pressure applied to the sensor may cause the wrinkled conductive layer to deform and crack and send a signal based on resistance. The stretchable strain sensor may be capable of measuring contractions of a tissue, detecting fluid flowing through a microfluidic channel, and detecting whether a microfluidic valve is closed or not.

A transfer system for transferring multiple microelements to a receiving substrate includes a main pick-up device, a testing device, and first and second carrier plates. The testing device includes a testing platform, a testing circuit, and multiple testing electrodes electrically connected to the testing circuit. The main pick-up device is operable to releasably pick up the microelements from the first carrier plate and position the microelements on the testing electrodes. The testing device is operable to test the microelements to distinguish unqualified ones of the microelements from qualified ones. The main pick-up device is operable to release the qualified ones of the microelements to the receiving substrate.

A surface monitoring device is for monitoring a contact surface of a detected object. The surface monitoring device and the detected object are disposed on a substrate. The surface monitoring device includes a resonant mechanical part, having a contact tip adjacent to the contact surface by a preset gap in a static state. A driving circuit, applying an AC input signal to drive the resonant mechanical part to cause the contact tip to vibrate with respect to the contact surface at a plurality of sampling frequencies. The contact tip substantially hits the contact surface in a tapping bandwidth within the sampling frequencies. An analysis circuit to analyze a ratio of an output voltage to an input voltage of the input signal and determine the tapping bandwidth, wherein the ratio in the tapping bandwidth is jumping to a flatten phase.