A process for manufacturing a MEMS device includes forming a first structural layer of a first thickness on a substrate. First trenches are formed through the first structural layer, and masking regions separated by first openings are formed on the first structural layer. A second structural layer of a second thickness is formed on the first structural layer in direct contact with the first structural layer at the first openings and forms, together with the first structural layer, thick structural regions having a third thickness equal to the sum of the first and the second thicknesses. A plurality of second trenches are formed through the second structural layer, over the masking regions, and third trenches are formed through the first and the second structural layers by removing selective portions of the thick structural regions.

In accordance with various embodiments, a method for processing a layer structure is provided, where the layer structure includes a first layer, a sacrificial layer arranged above the first layer, and a second layer arranged above the sacrificial layer, where the second layer includes at least one opening, and the at least one opening extends from a first side of the second layer as far as the sacrificial layer. The method includes forming a liner layer covering at least one inner wall of the at least one opening; forming a cover layer above the liner layer, where the cover layer extends at least in sections into the at least one opening; and wet-chemically etching the cover layer, the liner layer and the sacrificial layer using an etching solution, where the etching solution has a greater etching rate for the liner layer than for the cover layer.

In an embodiment a semiconductor transducer device includes a semiconductor body and a diaphragm having a first layer and a second layer, wherein a main extension plane of the diaphragm is arranged parallel to a surface of the semiconductor body, wherein the diaphragm is suspended at a distance from the semiconductor body in a direction perpendicular to the main extension plane of the diaphragm, wherein the second layer comprises titanium and/or titanium nitride, wherein the first layer comprises a material that is resistant to an etchant comprising fluorine or a fluorine compound, and wherein the second layer is arranged between the semiconductor body and the first layer.

In accordance with various embodiments, a method for processing a layer structure is provided, where the layer structure includes a first layer, a sacrificial layer arranged above the first layer, and a second layer arranged above the sacrificial layer, where the second layer includes at least one opening, and the at least one opening extends from a first side of the second layer as far as the sacrificial layer. The method includes forming a liner layer covering at least one inner wall of the at least one opening; forming a cover layer above the liner layer, where the cover layer extends at least in sections into the at least one opening; and wet-chemically etching the cover layer, the liner layer and the sacrificial layer using an etching solution, where the etching solution has a greater etching rate for the liner layer than for the cover layer.

An example microelectromechanical system (MEMS) force sensor is described herein. The MEMS force sensor can include a sensor die configured to receive an applied force. The sensor die can include a first substrate and a second substrate, where a cavity is formed in the first substrate, and where at least a portion of the second substrate defines a deformable membrane. The MEMS force sensor can also include an etch stop layer arranged between the first substrate and the second substrate, and a sensing element arranged on a surface of the second substrate. The sensing element can be configured to convert a strain on the surface of the membrane substrate to an analog electrical signal that is proportional to the strain.

The present invention provides a MEMS microphone comprising (i) a substrate layer, (ii) a fixed backplate, and (iii) an intermediate layer sandwiched between the substrate layer and the fixed backplate. The substrate layer has a first opening through the thickness of the substrate layer. The intermediate layer has a second opening through the thickness of the intermediate layer. The fixed backplate forms a ceiling of the second opening, and the second opening is larger than the first opening and extends into the first opening, forming a looped recess (“undercut”). The looped recess is defined by a looped ledge on the substrate, a looped sidewall around the second opening, and a looped ceiling from the fixed backplate. The looped sidewall and the looped ceiling are made of a same material.

An example microelectromechanical system (MEMS) force sensor is described herein. The MEMS force sensor can include a sensor die configured to receive an applied force. The sensor die can include a first substrate and a second substrate, where a cavity is formed in the first substrate, and where at least a portion of the second substrate defines a deformable membrane. The MEMS force sensor can also include an etch stop layer arranged between the first substrate and the second substrate, and a sensing element arranged on a surface of the second substrate. The sensing element can be configured to convert a strain on the surface of the membrane substrate to an analog electrical signal that is proportional to the strain.

The present invention provides a MEMS microphone comprising (i) a substrate layer, (ii) a fixed backplate, and (iii) an intermediate layer sandwiched between the substrate layer and the fixed backplate. The substrate layer has a first opening through the thickness of the substrate layer. The intermediate layer has a second opening through the thickness of the intermediate layer. The fixed backplate forms a ceiling of the second opening, and the second opening is larger than the first opening and extends into the first opening, forming a looped recess (“undercut”). The looped recess is defined by a looped ledge on the substrate, a looped sidewall around the second opening, and a looped ceiling from the fixed backplate. The looped sidewall and the looped ceiling are made of a same material.

A method for preparing and/or carrying out the structuring of a predetermined or predeterminable distinguished surface of a substrate body having a substrate material includes exposing the substrate material in at least one curved effective area to an electromagnetic field which in each of the at least one curved effective area causes a non-linear interaction between the electromagnetic field and the substrate material, and thus at least partially influencing the substrate material arranged in the curved effective area. After the structuring of the distinguished surface the distinguished surface has at least in certain areas at least one first curved progression which is at least partially determined and/or influenced by the curved shape of the at least one curved effective area. The nonlinear interaction causes at least one nonlinear absorption of the electromagnetic field in the substrate material.

In accordance with various embodiments, a method for processing a layer structure is provided, where the layer structure includes a first layer, a sacrificial layer arranged above the first layer, and a second layer arranged above the sacrificial layer, where the second layer includes at least one opening, and the at least one opening extends from a first side of the second layer as far as the sacrificial layer. The method includes forming a liner layer covering at least one inner wall of the at least one opening; forming a cover layer above the liner layer, where the cover layer extends at least in sections into the at least one opening; and wet-chemically etching the cover layer, the liner layer and the sacrificial layer using an etching solution, where the etching solution has a greater etching rate for the liner layer than for the cover layer.