Invensense, Inc.

Analog Devices,inc.

Sushil Bharatan

Thomas Chen

Aleksey Sergeyevich Khenkin

Renata Melamud Berger

Jeremy Parker

Xin Zhang

Joseph Seeger

Michael W Judy

Baris Cagdaser

Lee James Jacobson

Jicheng Yang

Erhan Polatkan Ata

Michael John Foster

Pirmin Rombach

Aleksey S Khenkin

Andrew Randles

Venkataraman Chandrasekaran

The present invention relates to a fixed-fixed membrane for a microelectromechanical system (MEMS) microphone. In one embodiment,

Fixed-fixed membrane for microelectromechanical system microphone

A micro-electro-mechanical system (MEMS) sensor can comprise a substantially rigid layer having a center. The MEMS sensor can further comprise a movable membrane that can be separated by a gap from, and be disposed substantially parallel to, the substantially rigid layer. The MEMS sensor can further include a plurality of pedestals extending into the gap, where a first pedestal of the plurality of pedestals can be of a first size, and be disposed a first distance from the center, and a second pedestal of the plurality of pedestals can be a second size different from the first size, and be disposed at a second distance from the center. In another aspect, the substantially rigid layer and the movable membrane can be suspended by a plurality of suspension points. In another aspect, at least one of the plurality of pedestals can be disposed so as to limit a deformation of the movable membrane.

Stress reduced diaphragm for a micro-electro-mechanical system sensor

A microelectromechanical microphone has a stationary region or another type of mechanically supported region that can mitigate or avoid mechanical instabilities in the microelectromechanical microphone. The stationary region can be formed in a diaphragm of the microelectromechanical microphone by rigidly attaching, via a rigid dielectric member, an inner portion of the diaphragm to a backplate of the microelectromechanical microphone. The rigid dielectric member can extend between the backplate and the diaphragm. In certain embodiments, the dielectric member can be hollow, forming a shell that is centrosymmetric or has another type of symmetry. In other embodiments, the dielectric member can define a core-shell structure, where an outer shell of a first dielectric material defines an inner opening filled with a second dielectric material. Multiple dielectric members can rigidly attach the diaphragm to the backplate. An extended dielectric member can rigidly attach a non-planar diaphragm to a backplate.

Microelectromechanical microphone having a stationary inner region

Microphone distortion reduction is presented herein. A system can comprise: a processor; and a memory that stores executable instructions that, when executed by the processor, facilitate performance of operations, comprising: obtaining a pressure-in to voltage-out transfer function representing a distortion of an output of a microphone corresponding to a stimulus of a defined sound pressure level that has been applied to the microphone; inverting an equation representing the pressure-in to voltage-out transfer function to obtain an inverse transfer function; and applying the inverse transfer function to the output to obtain a linearized output representing the stimulus. In one example, the obtaining of the pressure-in to voltage-out transfer function comprises: creating an ideal sine wave stimulus comprising the amplitude and fundamental frequency of the time domain waveform; and generating the equation based on a defined relationship between the ideal sine wave stimulus and the time domain waveform.

Microphone distortion reduction

A micro electro-mechanical system (MEMS) microphone is provided. The microphone includes: a package substrate having a port disposed through the package substrate, wherein the port is configured to receive acoustic waves; and a lid coupled to the substrate and forming a package. The MEMS microphone also includes a MEMS acoustic sensor disposed in the package and positioned such that the acoustic waves receivable at the port are incident on the MEMS acoustic sensor. The MEMS acoustic sensor includes: a back plate positioned over the port at a first location within the package; and a diaphragm positioned at a second location within the package, wherein a distance between the first location and the second location forms a defined sense gap, and wherein the MEMS microphone is designed to withstand a bias voltage between the diaphragm and the back plate greater than or equal to about 15 volts.

Integrated package forming wide sense gap micro electro-mechanical system microphone and methodologies for fabricating the same

A micro electro-mechanical system (MEMS) acoustic sensor is disclosed. The acoustic sensor comprises a backplate and a diaphragm. The acoustic sensor further comprises a flexible member and optional spacer member disposed between the backplate and the diaphragm resulting in a gap between the backplate and the diaphragm. The gap can vary in response to impinging pressure on the diaphragm based on the design of the flexible member and resulting in a variable capacitance between the backplate and the diaphragm. The change in the gap can result in a change in an electrical characteristic associated with the variable capacitance and can be converted to an electrical output signal corresponding to the impinging pressure on the diaphragm. The flexible member can be part of the backplate or diaphragm.

MEMS acoustic sensor comprising a non-perimeter flexible member

A micro electro-mechanical system (MEMS) microphone is provided. The MEMS microphone is configured to operate at a predetermined range of frequencies. The MEMS microphone has a tensioned membrane preset at a tension amount selected to cause the MEMS microphone to operate at a predetermined sensitivity level that is above a threshold sensitivity level. The tension amount is controlled based on a temperature applied to the tensioned membrane during a fabrication process. At least a portion of the tensioned membrane is sandwiched between a first conductive layer and a second conductive layer configured to equalize stress of the tensioned membrane.

MEMS microphone with tensioned membrane

A microphone system has a package with an interior chamber and an inlet aperture for receiving an acoustic signal, and a microphone die having a backplate and a diaphragm. The microphone is positioned within the package interior to form a front volume between the diaphragm and the inlet aperture. Accordingly, the microphone is positioned to form a back volume defined in part by the diaphragm within the interior chamber. The system also has a stop member positioned in the back volume so that the diaphragm is between the stop member and the backplate.

Microphone system with a stop member

A MEMS microphone has a stationary portion with a backplate having a plurality of apertures, and a diaphragm spaced from the backplate and having an outer periphery. As a condenser microphone, the diaphragm and backplate form a variable capacitor. The microphone also has a post extending between, and substantially permanently connected with, both the backplate and the diaphragm, and a set of springs securing the diaphragm to at least one of the post and the stationary portion. The post is positioned to be radially inward of the outer periphery of the diaphragm.

MEMS microphone with springs and interior support

A microphone system has a package with an interior, a MEMS microphone within the package interior and forming a backvolume between it and the package interior, and a MEMS valve coupled with at least one input aperture in the package. The package defines at least one input aperture (e.g., the prior noted aperture) for receiving an acoustic signal, and the MEMS microphone is mechanically coupled to at least a portion of one input aperture. The valve has a valve opening generally circumscribed by a valve seat. The valve is considered as having an open mode for permitting acoustic signal access into the package interior through the valve opening, and a closed mode for substantially preventing acoustic signal access into the package interior through the valve opening. The valve has a movable member configured to contact the valve seat when in the closed mode. This movable member is configured to move between the open mode and the closed mode in a direction that is generally perpendicular to the valve seat.

Microphone with variable low frequency cutoff

A MEMS microphone has an SOI wafer, a backplate formed in a portion of the SOI wafer, and a diaphragm adjacent to and movable relative to the backplate. The backplate has at least one trench that substantially circumscribes a central portion of the backplate.

Growing community of inventors

Burlington, MA, United States of America

Sushil Bharatan