B81C1/00158

Process of fabricating lateral mode capacitive microphone
11546711 · 2023-01-03 · ·

The present invention provides a process of fabricating a capacitive microphone such as a MEMS microphone. In the process, one electrically conductive layer is deposited on a removable layer, and then divided or cut into two divided layers, both of which remain in contact with the removable layer as they were. One of the two divided layers will become or include a movable or deflectable membrane/diaphragm that moves in a lateral manner relative to another layer, instead of moving toward/from another layer. A motional sensor is optionally fabricated within the microphone to estimate the noise introduced from acceleration or vibration of the microphone for the purpose of compensating the microphone output through a signal subtraction operation.

GRAPHENE TRANSDUCERS

The present application relates to graphene-based transducing devices, including micromechanical ultrasonic transducers and electret transducers. A micromachined ultrasonic transducer comprising: a backing layer, a spacer layer, and a diaphragm comprising a material selected from the group consisting of graphene, h-BN, MoS2, and combinations thereof, wherein the backing layer comprises a first etched semiconductor, glass, or polymer, wherein the spacer layer comprises a second etched semiconductor, glass, or polymer.

ULTRA-THIN SEMICONDUCTOR DIE WITH IRREGULAR TEXTURED SURFACES

The present disclosure is directed to at least one embodiment of a die including a sidewall having a uniform surface and an irregular surface. The uniform surface may be a scalloped surface and scallops of the scalloped surface are substantially the same size and shape relative to each other. The irregular surface has a more irregular texture as compared to the uniform surface. The irregular surface may include a plurality of randomly spaced high points and a plurality of randomly spaced low points that are between adjacent ones of the high points. In a method of manufacturing the die, a cavity is pre-formed in a substrate and a multilayer structure is formed on the substrate. The multilayer structure includes an active area that is aligned with and overlies the cavity. After the multilayer structure is formed, at least one recess is formed extending into the multilayer structure to the cavity. Forming the recess forms a die structure suspended above the cavity and an extension extending from the die structure to a suspension structure surrounding the die structure. The die structure is released from the die suspension structure by breaking the extension.

Membrane support for dual backplate transducers

A microfabricated structure includes a perforated stator; a first isolation layer on a first surface of the perforated stator; a second isolation layer on a second surface of the perforated stator; a first membrane on the first isolation layer; a second membrane on the second isolation layer; and a pillar coupled between the first membrane and the second membrane, wherein the first isolation layer includes a first tapered edge portion having a common surface with the first membrane, wherein the second isolation layer includes a first tapered edge portion having a common surface with the second membrane, and wherein an endpoint of the first tapered edge portion of the first isolation layer is laterally offset with respect to an endpoint of the first tapered edge portion of the second isolation layer.

MEMS DEVICE, ASSEMBLY COMPRISING THE MEMS DEVICE, AND METHODS FOR OPERATING THE MEMS DEVICE
20220380200 · 2022-12-01 ·

Proposed is a MEMS device comprising a layer stack having at least one second layer formed between a first layer and a third layer. At least one first cavity is formed in the second layer. The MEMS device further comprises a laterally deflectable member having an end connected to a sidewall of the first cavity and a free end. Further, the MEMS device includes a passive element rigidly tethered to the free end of the laterally deflectable element to follow movement of the laterally deflectable element. The laterally deflectable element and the passive element divide the first cavity into a first sub-cavity and a second sub-cavity. The first sub-cavity is in contact with an ambient fluid of the MEMS device via at least a first opening. Further, the second subcavity is in contact with the ambient fluid of the MEMS device via at least a second opening. The at least one first opening is formed in a different layer of the first layer and the third layer than the at least one second opening.

MEMS MICROPHONE AND PREPARATION METHOD THEREFOR
20220386052 · 2022-12-01 ·

A preparation method for a micro-electromechanical systems (MEMS) microphone includes the steps of: providing a silicon substrate having a silicon surface; forming an enclosed cavity in the silicon substrate; forming a plurality of spaced apart acoustic holes in the silicon substrate, each acoustic hole having two openings, one of which communicating with the cavity and the other one located on the silicon surface; forming a sacrificial layer on the silicon substrate, which includes a first filling portion, a second filling portion and a shielding portion; forming a polysilicon layer on the shielding portion; forming a recess in the silicon substrate on the side away from the silicon surface; and removing the first filling portion, the second filling portion and part of the shielding portion so that the recess is brought into communication with the cavity to form a back chamber, and that the polysilicon layer, the remainder of the shielding portion and the silicon substrate together delimit a hollow chamber, the hollow chamber communicating with the opening of the plurality of acoustic holes away from the cavity, completing the MEMS microphone.

ELECTROMECHANICAL MICROSYSTEM

An electromechanical microsystem including two electromechanical transducers, a first deformable diaphragm and a cavity hermetically containing a deformable medium keeping a constant volume under the action of a change in the external pressure. The first diaphragm forms at least one portion of a first wall of the cavity and has a freely deformable area. The free area cooperates with an external member so that its deformation induces, or is induced by, a movement of the external member. The electromechanical transducers are configured so that a first electromechanical transducer forms a portion of the first wall of the cavity, and a second electromechanical transducer forms at least one portion of the wall opposite to the first wall of the cavity.

ELECTROMECHANICAL MICROSYSTEM

An electromechanical microsystem including an electromechanical transducer, a deformable diaphragm and a cavity hermetically containing a deformable medium keeping a constant volume under the action of an external pressure change. The deformable diaphragm forms a wall of the cavity and has at least one free area so as to be elastically deformed. The electromechanical transducer is configured so that its movement depends on the change in the external pressure, and vice versa. The free area cooperates with an external member so that its deformation induces, or is induced by, a movement of the external member. Thus, the electromechanical microsystem is adapted to displace the external member or to detect a movement of this member, the electromechanical microsystem includes at least one pin, configured to bear on a peripheral portion of the free area so that a deformation of the free rea causes an inclination of the pin.

ELECTROMECHANICAL MICROSYSTEM

An electromechanical microsystem including an electromechanical transducer, a deformable diaphragm, a first cavity hermetically containing a deformable medium keeping a substantially constant volume under the action of an external pressure change and a second cavity. The deformable diaphragm forms a wall of the cavity and has at least one area freely deformable elastically. The free area also forms a wall of the second cavity. The electromechanical transducer is configured so that its movement depends on the external pressure change, and vice versa. A change in the external pressure in the first cavity induces a variation of the volume of the second cavity, or vice versa. Thus, the proposed electromechanical microsystem enables gripping of an object obstructing the opening of the second cavity and forms a microbarometer capable of converting at least one ambient pressure change into an electrical signal.

Method for manufacturing a microelectronic device comprising a membrane suspended above a cavity

A method for manufacturing a microelectronic device with a membrane suspended above at least one final cavity, may involve providing a supporting substrate having at least one elementary cavity, and a donor substrate. The method may include assembling the supporting and donor substrate, then thinning the donor substrate so as to form the membrane. Advantageously, the method may include forming at least one membrane anchoring pillar. After the forming of the at least one anchoring pillar, and after the assembling, the method may include etching the surface layer of the supporting substrate so as to widen the at least one elementary cavity, to form the final cavity, the etching being configured to selectively etch the surface layer with respect to the anchoring pillar.