The disclosure describes devices and methods of providing a DC bias voltage in a microphone assembly. Particularly, one implementation of such a device may be implemented on an integrated circuit that includes a direct current (DC) bias circuit. The DC bias circuit may be coupled to a transducer and configured to supply a DC bias signal to the transducer. The DC bias circuit includes a multi-stage charge pump and a low pass filter (LUFF) circuit. The multi-stage charge pump includes transistors that are fabricated with deep trench isolation (DTI).

The disclosure describes devices and methods of providing a DC bias voltage in a microphone assembly. Particularly, one implementation of such a device may be implemented on an integrated circuit that includes a direct current (DC) bias circuit. The DC bias circuit may be coupled to a transducer and configured to supply a DC bias signal to the transducer. The DC bias circuit includes a multi-stage charge pump and a low pass filter (LUFF) circuit. The multi-stage charge pump includes transistors that are fabricated with deep trench isolation (DTI).

A piezoelectric microelectromechanical systems diaphragm microphone can be mounted on a printed circuit board. The microphone can include a substrate with an opening between a bottom end of the substrate and a top end of the substrate. The microphone can have two or more piezoelectric film layers disposed over the top end of the substrate and defining a diaphragm structure. Each of the two or more piezoelectric film layers can have a predefined residual stress that substantially cancel each other out so that the diaphragm structure is substantially flat with substantially zero residual stress. The microphone can include one or more electrodes disposed over the diaphragm structure. The diaphragm structure is configured to deflect when the diaphragm is subjected to sound pressure via the opening in the substrate.

A piezoelectric microelectromechanical systems diaphragm microphone can be mounted on a printed circuit board. The microphone can include a substrate with an opening between a bottom end of the substrate and a top end of the substrate. The microphone can have two or more piezoelectric film layers disposed over the top end of the substrate and defining a diaphragm structure. Each of the two or more piezoelectric film layers can have a predefined residual stress that substantially cancel each other out so that the diaphragm structure is substantially flat with substantially zero residual stress. The microphone can include one or more electrodes disposed over the diaphragm structure. The diaphragm structure is configured to deflect when the diaphragm is subjected to sound pressure via the opening in the substrate.

A robust MEMS transducer includes a kinetic energy diverter disposed within its frontside cavity. The kinetic energy diverter blunts or diverts kinetic energy in a mass of air moving through the frontside cavity, before that kinetic energy reaches a diaphragm of the MEMS transducer. The kinetic energy diverter renders the MEMS transducer more robust and resistant to damage from such a moving mass of air.

A robust MEMS transducer includes a kinetic energy diverter disposed within its frontside cavity. The kinetic energy diverter blunts or diverts kinetic energy in a mass of air moving through the frontside cavity, before that kinetic energy reaches a diaphragm of the MEMS transducer. The kinetic energy diverter renders the MEMS transducer more robust and resistant to damage from such a moving mass of air.

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.

A microelectromechanical system (MEMS) transducer includes a transducer substrate, a diaphragm, and a stiffening member. A first side of the diaphragm is coupled to the transducer substrate. A second side of the diaphragm is coupled to the stiffening member. The stiffening member includes a plurality of fingers extending inwards from a perimeter of an aperture defined by the transducer substrate.

A microelectromechanical system (MEMS) transducer includes a transducer substrate, a diaphragm, and a stiffening member. A first side of the diaphragm is coupled to the transducer substrate. A second side of the diaphragm is coupled to the stiffening member. The stiffening member includes a plurality of fingers extending inwards from a perimeter of an aperture defined by the transducer substrate.

A microphone unit includes: an audio data acquisition unit that acquires speech as audio data; an audio data registration unit that registers verification audio data obtained by extracting a feature point from the audio data; an evaluation audio data acquisition unit that acquires speech that is input to a first microphone as evaluation audio data; a verification unit that verifies whether or not a speaker who uttered speech that is based on the evaluation audio data is a speaker who uttered speech that is based on the verification audio data, based on the verification audio data and a feature point extracted from the evaluation audio data; and a verification result output unit that outputs a result of verification performed by the verification unit.