Abstract: In an embodiment, a method for fabricating a Microelectromechanical System (MEMS) microphone includes depositing, on a frontside of a wafer, a first oxide layer over a silicon nitride thin film and over and adjacent the wafer, wherein the silicon nitride thin film is disposed over the wafer, depositing a membrane protection layer over the first oxide layer between a first side of a first cavity formed in the wafer and a second side of a second cavity formed in the wafer, depositing a second oxide layer over and adjacent the membrane protection layer, depositing a first membrane nitride layer over the second oxide layer, depositing a membrane polysilicon layer over the first membrane nitride layer, depositing a second membrane nitride layer over the membrane polysilicon layer, depositing a third oxide layer over the second membrane nitride layer and depositing a fourth oxide layer over the third oxide layer.

Abstract: A microelectromechanical (MEMS) microphone with membrane trench reinforcements and method of fabrication is provided. The MEMS microphone includes a flexible plate and a rigid plate mechanically coupled to the flexible plate. The MEMS microphone includes a stoppage member affixed to the rigid plate and extending perpendicular relative to a surface of the rigid plate opposite the surface of the flexible plate. The stoppage member limits motion of the flexible plate. The rigid plate includes a reverse bending edge that include a first lateral etch stop that includes a first corner radius and a second lateral etch stop that includes a second corner radius. The first corner radius is more than 100 nanometers and the second corner radius is more than 25 nanometers. Further, a lateral step width between the first corner radius and the second corner radius is less than around 4 micrometers.

Abstract: A microelectromechanical (MEMS) microphone with membrane trench reinforcements and method of fabrication is provided. The MEMS microphone includes a flexible plate and a rigid plate mechanically coupled to the flexible plate. The MEMS microphone includes a stoppage member affixed to the rigid plate and extending perpendicular relative to a surface of the rigid plate opposite the surface of the flexible plate. The stoppage member limits motion of the flexible plate. The rigid plate includes a reverse bending edge that includes a first lateral etch stop that includes a first corner radius and a second corner radius. The first corner radius is more than 100 nanometers and the second corner radius is more than 25 nanometers. Further, a lateral step width between the first corner radius and the second corner radius is less than around 4 micrometers.

Abstract: A microelectromechanical (MEMS) microphone with membrane trench reinforcements and method of fabrication is provided. The MEMS microphone includes a flexible plate and a rigid plate mechanically coupled to the flexible plate. The MEMS microphone includes a stoppage member affixed to the rigid plate and extending perpendicular relative to a surface of the rigid plate opposite the surface of the flexible plate. The stoppage member limits motion of the flexible plate. The rigid plate includes a reverse bending edge that include a first lateral etch stop that includes a first corner radius and a second lateral etch stop that includes a second corner radius. The first corner radius is more than 100 nanometers and the second corner radius is more than 25 nanometers. Further, a lateral step width between the first corner radius and the second corner radius is less than around 4 micrometers.

Abstract: A MEMS microphone including a carrier board and a MEMS chip mounted thereon over a sound opening. A filter chip includes a bulk material with an aperture covered and closed by a mesh. The mesh includes a layer of the filter chip with parallel through-going first holes structured in the layer. The filter chip is arranged in or on the carrier board such that the mesh covers the sound opening.

Abstract: A MEMS microphone is provided comprising a carrier board and a MEMS chip mounted thereon over a sound opening. A filter chip comprises a bulk material with an aperture covered and closed by a mesh. The mesh comprises a layer of the filter chip with parallel through-going first holes structured in the layer. The filter chip is arranged in or on the carrier board such that the mesh covers the sound opening.

Abstract: A non-uniform stress distribution of a MEMS microphone having a non-circular shape is compensated by a structured back plate that has a compensating structure to provide a stress distribution opposite to that of the membrane.

Abstract: A package for a top port microphone with an enlarged back volume. The package includes on a substrate a lid enclosing thereunder a total volume and accommodating a MEMS chip and an ASIC. A stopper seals the ASIC against the lid thereby separating and dividing the total volume under the lid in a volume extension and a remaining volume. The volume extension can be used to arbitrarily enlarge the back volume or the front volume dependent on a placement of a sound port to the volume extension or the remaining volume. A sound path connects the volume extension and a partial volume enclosed between MEMS chip and substrate.

Abstract: A top-port MEMS-microphone has an upper side and a bottom side. The microphone includes a MEMS chip with a monolithically connected protection element at the upper side, a backplate, and a membrane. The microphone also includes a sound inlet at the upper side and a mechanical or electrical connection at the bottom side.

Abstract: A package for a top port microphone with an enlarged back volume comprises on a substrate a lid enclosing thereunder a total volume and accommodating a MEMS chip and an ASIC. A stopper seals the ASIC against the lid thereby separating and dividing the total volume under the lid in a volume extension and a remaining volume. The volume extension can be used to arbitrarily enlarge the back volume or the front volume dependent on a placement of a sound port to the volume extension or the remaining volume. A sound path connects the volume extension and a partial volume enclosed between MEMS chip and substrate.

Abstract: A non-uniform stress distribution of a MEMS microphone having a non-circular shape is compensated by a structured back plate that has a compensating structure to provide a stress distribution opposite to that of the membrane.

Abstract: A top-port MEMS-microphone has an upper side and a bottom side. The microphone includes a MEMS chip with a monolithically connected protection element at the upper side, a backplate, and a membrane. The microphone also includes a sound inlet at the upper side and a mechanical or electrical connection at the bottom side.

Abstract: The invention relates to an acoustic micro-electrical-mechanical-system (MEMS) transducer formed on a single die based on a semiconductor material and having front and back surface parts opposed to each other. The invention further relates to a method of manufacturing such an acoustic MEMS transducer. The acoustic MEMS transducer comprises a cavity formed in the die to thereby provide a back volume with an upper portion facing an opening of the cavity and a lower portion facing a bottom of the cavity. A back plate and a diaphragm are arranged substantially parallel with an air gap there between and extending at least partly across the opening of the cavity, with the back plate and diaphragm being integrally formed with the front surface part of the die. The bottom of the cavity is bounded by the die. The diaphragm may be arranged above the back plate and at least partly extending across the back plate.

Abstract: The invention relates to an acoustic micro-electrical-mechanical-system (MEMS) transducer formed on a single die based on a semiconductor material and having front and back surface parts opposed to each other. The invention further relates to a method of manufacturing such an acoustic MEMS transducer. The acoustic MEMS transducer comprises a cavity formed in the die to thereby provide a back volume with an upper portion facing an opening of the cavity and a lower portion facing a bottom of the cavity. A back plate and a diaphragm are arranged substantially parallel with an air gap there between and extending at least partly across the opening of the cavity, with the back plate and diaphragm being integrally formed with the front surface part of the die. The bottom of the cavity is bounded by the die. The diaphragm may be arranged above the back plate and at least partly extending across the back plate.