MEMS sound transducer element
A MEMS sound transducer element is operable in an audio and an ultrasonic range. The MEMS sound transducer element includes a first electrode structure, wherein a conductive material of the first electrode structure includes a plurality of electrically isolated electrode segments, and a second electrode structure spaced apart from the first electrode structure, wherein the first electrode structure and the second electrode structure are operable as an audio sound transducer. A first subset of the plurality of electrically isolated electrode segments of the first electrode structure is, in conjunction with the second electrode structure, operable as an ultrasonic or audio emitter, and a second subset of the plurality of the electrically isolated electrode segments of the first electrode structure is, in conjunction with the second electrode structure, operable as an ultrasonic or audio receiver.
1 . A MEMS sound transducer element operable in an audio and an ultrasonic range, comprising:
a first electrode structure, wherein a conductive material of the first electrode structure comprises a plurality of electrically isolated electrode segments;
a second electrode structure spaced apart from the first electrode structure by a cavity;
wherein the first electrode structure and the second electrode structure are operable as an audio sound transducer;
wherein a first subset of the plurality of electrically isolated electrode segments of the first electrode structure is, in conjunction with the second electrode structure, operable as an ultrasonic or audio emitter;
wherein a second subset of the plurality of the electrically isolated electrode segments of the first electrode structure is, in conjunction with the second electrode structure, operable as an ultrasonic or audio receiver; and
wherein the first electrode structure is a counter electrode and wherein the second electrode structure is a single membrane element parallel to each of the plurality of electrically isolated electrode segments of the first electrode structure.
2 . The MEMS sound transducer element according to claim 1 ,
wherein the first electrode structure comprises a dielectric separation structure provided in the conductive material of the first electrode structure for providing the plurality of electrically isolated electrode segments of the first electrode structure.
3 . The MEMS sound transducer element according to claim 2 ,
wherein the dielectric separation structure comprises a gap in the conductive material of the first electrode structure, which gap is filled with a dielectric material.
4 . The MEMS sound transducer element according to claim 2 ,
wherein the dielectric separation structure comprises an open polygon shape or a closed polygon shape in the first electrode structure for providing the plurality of electrically isolated electrode segments.
5 . The MEMS sound transducer element according to claim 2 ,
wherein the dielectric separation structure comprises at least one of an open or closed circumferential shape, an open or closed ring shape, an open or closed square shape, and an open or closed ellipse shape in the first electrode structure for providing the plurality of electrically isolated electrode segments.
6 . The MEMS sound transducer element according to claim 2 ,
wherein the dielectric separation structure comprises at least one of a line shape, a meander shape, and a sinusoidal shape in the first electrode structure for providing the plurality of electrically isolated electrode segments.
7 . The MEMS sound transducer element according to claim 2 , further comprising:
a third electrode structure comprising a conductive material,
wherein the third electrode structure comprises a further dielectric separation structure provided in the conductive material of the third electrode structure for providing a plurality of electrically isolated electrode segments in the third electrode structure.
8 . The MEMS sound transducer element according to claim 7 ,
wherein the further dielectric separation structure comprises at least one of an open or closed polygon shape, an open or closed circumferential shape, an open or closed ring shape, an open or closed square shape, an open or closed ellipse shape, a line shape, a meander shape, and a sinusoidal shape for providing the plurality of electrically isolated electrode segments in the third electrode structure.
9 . The MEMS sound transducer element according to claim 7 ,
wherein the first subset of the plurality of electrically isolated electrode segments of the first electrode structure and a first subset of the plurality of electrically isolated electrode segments of the third electrode structure are, in conjunction with the second electrode structure, operable as the ultrasonic or audio emitter, and
wherein the second subset of the plurality of electrically isolated electrode segments of the first electrode structure and a second subset of the plurality of electrically isolated electrode segments of the third electrode structure are, in conjunction with the second electrode structure, operable as the ultrasonic or audio receiver.
10 . The MEMS sound transducer element according to claim 7 ,
wherein the dielectric separation structure of the first electrode structure and the dielectric separation structure of the third electrode structure are arranged in a mirrored configuration.
11 . The MEMS sound transducer element according to claim 7 ,
wherein the first, second and third electrode structures are arranged in a double counter electrode configuration,
wherein the first electrode structure is a first counter electrode, the second electrode structure is a membrane element, and the third electrode structure is a second counter electrode of the audio sound transducer, and
wherein the membrane element is arranged between the first and second counter electrodes.
12 . A sound transducer device, comprising:
the MEMS sound transducer element according to claim 1 , and
a controller configured to operate the MEMS sound transducer element in the audio and the ultrasonic ranges.
13 . The sound transducer device according to claim 12 ,
wherein the controller is configured to detect, in the audio range, an audio output signal of the MEMS sound transducer element between the first and second electrode structures, and
wherein the controller is configured to
excite, in the ultrasonic range, the first subset of the electrically isolated electrode segments of the first electrode structure, in conjunction with the second electrode structure, to operate as the ultrasonic emitter, and
to read out the second subset of the electrically isolated electrode segments of the first electrode structure, in conjunction with the second electrode structure, to operate as the ultrasonic receiver.
14 . The sound transducer device according to claim 12 ,
wherein the MEMS sound transducer element comprises a third electrode structure comprising a conductive material,
wherein the third electrode structure comprises a further dielectric separation structure in the conductive material of the third electrode structure for providing a plurality of electrically isolated electrode segments of the third electrode structure, and
wherein the controller is configured to
differentially read out the second subset of the electrically isolated electrode segments of the first electrode structure and a second subset of the electrically isolated electrode segments of the third electrode structure, in order to operate, in conjunction with the second electrode structure, as the ultrasonic receiver.