Various embodiments of the present disclosure are directed towards a method to roughen a crystalline layer. A crystalline layer is deposited over a substrate. A mask material is diffused into the crystalline layer along grain boundaries of the crystalline layer. The crystalline layer and the mask material may, for example, respectively be or comprise polysilicon and silicon oxide. Other suitable materials are, however, amenable. An etch is performed into the crystalline layer with an etchant having a high selectivity for the crystalline layer relative to the mask material. The mask material defines micro masks embedded in the crystalline layer along the grain boundaries. The micro masks protect underlying portions of the crystalline layer during the etch, such that the etch forms trenches in the crystalline layer where unmasked by the micro masks.

A diaphragm of a MEMS microphone is configured to generate a displacement thereof in response to an applied acoustic pressure, and the diaphragm includes a plurality of vent holes having a bent shape to increase the length of the vent holes.

A pressure sensor has a substrate having a diaphragm, a cavity portion that is positioned on one side of the diaphragm, and a ceiling portion that is disposed opposite to the diaphragm via the cavity portion, and unevenness is formed on a surface of the substrate facing the cavity portion. In addition, the unevenness has a plurality of recessed portions.

A semiconductor structure includes a first device and a second device. The first device includes a plate including a plurality of apertures, a membrane disposed opposite to the plate and including a plurality of corrugations facing the plurality of apertures, and a conductive plug extending from the plate through the membrane. The second device includes a substrate and a bond pad disposed over the substrate, wherein the conductive plug is bonded with the bond pad to integrate the first device with the second device, and the plate is an epitaxial (EPI) silicon layer or a silicon-on-insulator (SOI) substrate.

A MEMS sensor including a diaphragm, a base surface area of the diaphragm being delimited with the aid of a peripheral wall structure, and the base surface area including at least two subareas, of which at least one of the subareas is deflectably situated, and the at least two subareas being separated from one another with the aid of at least one separating structure or being delimited by the latter. The separating structure includes at least one fluid through-opening for the passage of fluid.

The present disclosure relates to a microphone. In some embodiments, the microphone may comprise a diaphragm, a backplate, and a sidewall stopper. The diaphragm has a venting hole disposed therethrough. The backplate is disposed over and spaced apart from the diaphragm. The sidewall stopper is disposed along a sidewall of the diaphragm exposing to the venting hole. Thus, the sidewall stopper is not limited by a distance between the movable part and the stable part of the microphone. Also, the sidewall stopper does not alternate the shape of movable part, and thus will less likely introduce crack to the movable part. In some embodiments, the sidewall stopper may be formed like a sidewall stopper by a self-alignment process, such that no extra mask is needed.

A MEMS microphone includes a substrate. A dielectric layer is disposed on the substrate, having an opening and includes: indent region surrounding the opening; pillars extending from an indent surface at the indent region to the substrate; and an outer part surrounding the indent region and disposed on the substrate. A signal sensing space is created at the indent region between the pillars and between the pillars and the outer part. A first electrode layer is disposed on the indent surface of the dielectric layer. A second electrode layer is disposed on the substrate. A sensing diaphragm is held by the dielectric layer, including two elastic diaphragms supported by the dielectric layer; and a conductive plate between the first elastic diaphragm and the second elastic diaphragm. The conductive plate has a central part embedded in the holding structure and a peripheral part extending into the signal sensing space.

A microelectromechanical systems (MEMS) package with roughness for high quality anti-stiction is provided. A device substrate is arranged over a support device. The device substrate comprises a movable element with a lower surface that is rough and that is arranged within a cavity. A dielectric layer is arranged between the support device and the device substrate. The dielectric layer laterally encloses the cavity. An anti-stiction layer lines the lower surface of the movable element. A method for manufacturing the MEMS package is also provided.

Provided are a method for preparing a silicon wafer with a rough surface and a silicon wafer, for solving the problem that a viscous force is likely to be generated when a smooth surface of the silicon wafer approaches another film layer. The method includes: depositing a porous oxide film layer on a surface of the first silicon planar layer that has been subjected to planar planarization, and then etching the porous oxide film layer by XeF.sub.2 vapor etching, during which XeF.sub.2 gas passes through the porous oxide film layer to etch the first silicon planar layer in an irregular way. Therefore, the first silicon planar layer has a greater surface roughness. When the silicon wafer approaches to another film layer, the viscous force generated therebetween is reduced, improving the sensitivity of the MEMS device and reducing the probability of out-of-work MEMS devices.

A micro-electro-mechanical device, comprising a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region facing the first buried cavity; a second cavity facing the first buried cavity; a decoupling trench extending from the monolithic body and separating the sensitive region from a peripheral portion of the monolithic body; a cap die, forming an ASIC, bonded to and facing the first face of the monolithic body; and a first gap between the cap die and the monolithic body. The device also comprises at least one spacer element between the monolithic body and the cap die; at least one stopper element between the monolithic body and the cap die; and a second gap between the stopper element and one between the monolithic body and the cap die. The second gap is smaller than the first gap.