Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.v.

Robert Bosch Gmbh

Technische Universitaet Dresden

Holger Conrad

Harald Schenk

Sergiu Langa

Thilo Sandner

Bert Kaiser

Matthieu Gaudet

Klaus Schimmanz

Thomas Klose

Thomas Grasshoff

Denis Jung

Michael Stolz

Anartz Unamuno

Christian Schirrmann

Fabian Zimmer

Jorge Mario Monsalve Guaracao

Jan-Uwe Schmidt

Sebastian Uhlig

The invention generally relates to drives for microelectromechanical acoustic pressure-generating device, which may be implemented in a microelectromechanical system (MEMS). In some embodiments of the invention, the microelectromechanical acoustic pressure-generating device is implemented in a chip/die, e.g. in form of a System-on-Chip (SoC) or a System-in-Package (SiP). Further embodiments of the invention relate to the use of such acoustic pressure-generating device in a microelectromechanical loudspeaker system, for example, headphones, hearing-aids, or the like. Embodiments of the invention relate to the miniaturization of the device. Some of the embodiments focus on countermeasures that reduce the pull-in force, which can facilitate further miniaturization of the microelectromechanical acoustic pressure-generating device.

Microelectromechanical acoustic pressure-generating device with improved drive

Proposed is a MEMS device comprising a layer stack having at least one second layer formed between a first layer and a third layer. A cavity is formed in the second layer. The MEMS device further comprises two laterally deflectable elements arranged laterally spaced apart in the cavity. Each of the two laterally deflectable elements comprises a respective end connected to a side wall of the cavity. Additionally, the MEMS device comprises a connecting element connected to the two laterally deflectable elements to couple the movement of the two laterally deflectable elements. A plurality of first fingers are arranged discretely spaced between the two laterally deflectable elements on the side wall of the cavity. Further, a plurality of second fingers are arranged discretely spaced between the two laterally deflectable elements on the connecting element. The plurality of second fingers interdigitate with the plurality of first fingers. Further, the plurality of second fingers are laterally displaceable relative to the plurality of first fingers upon deformation of the two laterally deflectable elements such that the plurality of first fingers and the plurality of second fingers define a plurality of volume variable sub-cavities within the cavity. Each of the plurality of sub-cavities is in contact with an ambient fluid of the MEMS device via a respective opening. In case of adjacent sub-cavities of the plurality of sub-cavities, the respective opening of one sub-cavity of the adjacent sub-cavities is formed in a different layer of the first layer, the second layer and the third layer than the opening of the other sub-cavity of the adjacent sub-cavities.

MEMS device, assembly comprising the MEMS device, and method of operating the MEMS device

A planar micromechanical actuator suspended on opposing suspension zones including a neutral axis between the opposing suspension zones, first to fourth segments into which the planar micromechanical actuator is segmented between the opposing suspension zones, each including a first electrode and a second electrode which form a capacitor and are isolatedly affixed to each other at opposite ends of the respective segment along a direction between the opposing suspension zones so as to form a gap between the first and second electrode along a thickness direction, the gap being offset to the neutral axis along the thickness direction, and wherein the first to fourth segments are configured such that the planar micromechanical actuator deflects into the thickness direction by the first and fourth segment bending into the thickness direction and the second and third segments bending contrary to the thickness direction upon a voltage being applied to the first and second electrodes of the first to fourth segments.

Micromechanical devices with mechanical actuators

A MEMS transducer for interacting with a volume flow of a fluid includes a substrate which includes a layer stack having a plurality of layers which form a plurality of substrate planes, and which includes a cavity within the layer stack. The MEMS transducer includes an electromechanical transducer connected to the substrate within the cavity and including an element which is deformable within at least one plane of movement of the plurality of substrate planes, deformation of the deformable element within the plane of movement and the volume flow of the fluid being causally correlated. The MEMS transducer includes an electronic circuit arranged within a layer of the layer stack, the electronic circuit being connected to the electromechanical transducer and being configured to provide a conversion between a deformation of the deformable element and an electric signal.

MEMS transducer for interacting with a volume flow of a fluid, and method of producing same

A MEMS includes a substrate having a cavity, and a moveable element arranged in the cavity, the moveable element including a first electrode, a second electrode and a third electrode that is arranged between the first electrode and the second electrode and is fixed in an electrically insulated manner from the same at discrete areas. The moveable element is configured to perform a movement along a movement direction in a substrate plan in response to an electric potential between the first electrode and the third electrode or in response to an electric potential between the second electrode and the third electrode. A dimension of the third electrode perpendicular to the substrate plane is lower than a dimension of the first electrode and a dimension of the second electrode perpendicular to the substrate plane.

MEMS and method of manufacturing the same

A micromechanical device with electrostatically caused deflection by a plate capacitor extending along and spaced apart from the neutral fiber of the deflectable element is improved with regard to its manufacturing complexity and/or with regard to its operating characteristics, such as, for example, maximum voltage applicable or deflectability, by using a continuous insulation layer between the distal and proximal electrodes of the plate capacitor, or else the proximal electrode is structured so as to have gaps at the segment boundaries where the distal electrode is mechanically fixed so as to be laterally spaced apart from the distal electrode. Both procedures avoid the problems of generating a roughness of the surface of the proximal electrode facing the distal electrode, as would otherwise be necessitated by etching an insulation layer for providing spacers between the distal and proximal electrodes at the segment boundaries.

Electrostatically deflectable micromechanical device

A MEMS transducer for interacting with a volume flow of a fluid includes a substrate including a cavity, and an electromechanical transducer connected to the substrate in the cavity and including an element deformable along a lateral movement direction, wherein a deformation of the deformable element along the lateral movement direction and the volume flow of the fluid are causally related.

MEMS transducer for interacting with a volume flow of a fluid and method for manufacturing the same

Micromechanical devices include actively deflectable elements. The activation is performed by a layer stack which causes the deflection responsive to attractive forces acting upon the layers of the layer stack.

Micromechanical device with an actively deflectable element

The force on the electrodes of an electrostatic field is used so that lateral tensile or compressive forces result which can deform a deformable element or can strongly deflect a deflectable structure. For this, a micromechanical device includes, apart from an electrode and a deformable element, an insulating spacer layer via which the electrode is fixed to the deformable element, wherein the insulating spacer layer is structured into several spaced-apart segments along a lateral direction, so that by applying an electric voltage between the electrode and the deformable element lateral tensile or compressive forces bending the deformable element along the lateral direction result. Thereby, the problem that normally accompanies electrostatic drives, namely the problem of the pull-in effect, is overcome. The deflection of the deformable element can be much larger than the gaps of the two electrodes, i.e. the above-mentioned electrode and the deformable element. A usage as a sensor is also possible.

Micromechanical device

A micromechanical mirror arrangement comprising a mirror plate () which forms a translation mirror, which is connected via at least one holding element (), preferably two or more holding elements, to a frame structure () and is movable in translation relative to this frame structure, characterized in that the connection region () of at least one holding element (), preferably of all holding elements, with the mirror plate () is arranged inwardly offset, viewed from the outer margin () of the mirror plate toward to the center () of the mirror plate.

Reduction of the dynamic deformation of translational mirrors using inertial masses

A micromechanical element includes a plate-shaped micromechanical functional element, an inner frame and an outer frame. Thereby, a curvature of a main face of the plate-shaped micromechanical functional element is variable. The inner frame encloses the plate-shaped micromechanical functional element along an edge of the main face and is connected to the plate-shaped micromechanical functional element via a plurality of connecting pieces. The outer frame is connected to the inner frame via at least two holding elements. The inner frame is connected to the plate-shaped micromechanical functional element and the outer frame, such that a first angle between the main face of the plate-shaped micromechanical functional element and a main face of the inner frame is smaller than a second angle between a main face of the outer frame and the main face of the inner frame, when the main face of the plate-shaped micromechanical functional element is in a bent state.

Micromechanical element

A micromechanical element includes a movable functional element, a first retaining element, a second retaining element, a third retaining element, and a fourth retaining element. The first retaining element and the functional element are connected at a first junction, the second retaining element and the functional element are connected at a second junction, the third retaining element and the functional element are connected at a third junction, and the fourth retaining element and the functional element are connected at a fourth junction. In addition, the first retaining element and the second retaining element each include a piezoelectric driving element, the driving element of the first retaining element and the driving element of the second retaining element being configured to move the functional element in accordance with electric excitation.

Micromechanical element and sensor for monitoring a micromechanical element

The invention relates to deflectable micromechanical systems as well as their use in which the deflection of at least one deflectable element can be determined. In accordance with the invention, a deflectable element is held with at least one spring element and at least one unit detecting the deflection is present. It is formed as a piezoresistive sensor with contacts arranged at least at a spacing from one another and in a region deforming on deflection. The contacts are connected to an electrical voltage source. An inhomogeneous electrical field is formed perpendicular to the contact surfaces in the depth direction so that the electrical resistance between contacts varying in dependence on the deflection can be detected as a measure for the position. The deforming region is formed from electrically conductive or semiconductive material.

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Dresden, Germany

Holger Conrad