# US 10,375,483 B2 · MEMS device and process > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,375,483 B2 - Document ID: US10375483B2 - Status: Granted - Kind: B2 - Application number: 15/636,019 - Filed: 2017-06-28 - Published: 2018-01-04 - Granted: 2019-08-06 - Earliest claimed: 2016-06-30 - Assignees: Cirrus Logic, Inc. - Applicants: Cirrus Logic International Semiconductor Ltd. - Inventors: Scott Lyall Cargill - Web page: https://patentgrep.com/patent/US10375483B2 ## CPC - H04R 19/04: Microphones (H04R19/01 takes precedence) - B81B 3/0027: {Structures for transforming mechanical energy, e.g. potential energy of a spring into translation, sound into translation} - B81B 3/0072: {For controlling internal stress or strain in moving or flexible elements, e.g. stress compensating layers} - B81B 7/0016: {Protection against shocks or vibrations, e.g. vibration damping} - B81C 1/00666: {Treatments for controlling internal stress or strain in MEMS structures} - H04R 7/20: Securing diaphragm or cone resiliently to support by flexible material, springs, cords, or strands - B81B 2201/0257: Microphones or microspeakers - B81B 2203/0127: Diaphragms, i.e. structures separating two media that can control the passage from one medium to another; Membranes, i.e. diaphragms with filtering function - B81B 2203/0315: Cavities - H04R 7/18: at the periphery - H04R 19/005: {using semiconductor materials} - H04R 2201/003: Mems transducers or their use - H04R 2499/11: Transducers incorporated or for use in hand-held devices, e.g. mobile phones, PDA's, camera's - H04R: LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS (producing sounds with frequency not determined by supply frequency G10K) - B81B: MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES (piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/00, H10N35/00) - B81C: PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS (making microcapsules or microballoons B01J13/02; processes or apparatus specially adapted for the manufacture or treatment of piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/01) ## Abstract The application describes MEMS transducers comprising a flexible membrane supported at a supporting edge relative to a substrate and further comprising one or more unbound edges. The shape of the unbound edge is selected so that the flexible membrane tends to bend along more than one bend axis in the region of the supporting edge. ## Claims ### Claim 1 A MEMS transducer comprising a flexible membrane supported at a plurality of supporting edges relative to a substrate, the flexible membrane comprising an active central region and a plurality of supporting arms, each supporting arm extending laterally from the central region, wherein each supporting arm comprises a first unbound edge portion which traces a path from a first endpoint of the first unbound edge at, or near, a first end of the supporting edge, wherein a first path segment is defined between first and second path points on the first unbound edge portion of one said supporting arm, and wherein the first path segment traces a path which varies in distance from a straight line path between the first and second path points, the first path segment comprising at least two bendpoints at which the flexible membrane tends to bend in response to a given deflection of the flexible membrane. ### Claim 2 (depends on 1) A MEMS transducer as claimed in claim 1, comprising a second unbound edge portion which traces a path from a first endpoint of the second unbound edge at, or near, a second end of the supporting edge, wherein a second path segment of the second unbound edge is defined between first and second path points on the second unbound edge portion, and wherein the second path segment traces a path which varies in distance from a straight line path between the first and second path points, the second path segment comprising one or more bendpoints at which the flexible membrane tends to bend in response to a given deflection of the flexible membrane. ### Claim 3 (depends on 2) A MEMS transducer as claimed in claim 2, wherein a bendpoint of the first segment corresponds to a bendpoint of the second segment, said corresponding bendpoints forming a pair of bendpoints. ### Claim 4 (depends on 3) A MEMS transducer as claimed in claim 3, wherein a line intersecting the pair of bendpoints defines a bend axis of the flexible membrane. ### Claim 5 (depends on 4) A MEMS transducer as claimed in claim 4, wherein the flexible membrane comprises a plurality of bend axes in a peripheral region of the membrane at, or near, the supporting edge. ### Claim 6 (depends on 5) A MEMS transducer as claimed in claim 5, wherein the bend axes are substantially parallel to each other and wherein a first bend axis extends along, or substantially parallel to, the supporting edge. ### Claim 7 (depends on 5) A MEMS transducer as claimed in claim 5, wherein the distance between a first pair of bendpoints defining a first bend axis is substantially equal to the distance between another pair of bendpoints defining another bend axis. ### Claim 8 (depends on 1) A MEMS transducer as claimed in claim 1, wherein at least one of the bendpoints forms a stationary point on the path traced by the path segment. ### Claim 9 (depends on 8) A MEMS transducer as claimed in claim 8, wherein the, or one of the, stationary point(s) comprises a turning point. ### Claim 10 (depends on 8) A MEMS transducer as claimed in claim 8, wherein the, or one of the, stationary point(s) comprises an undulation point. ### Claim 11 (depends on 1) A MEMS transducer as claimed in claim 1, wherein the, or each, path segment traces a path which is at least 10% longer than the straight line path between associated first and second path points. ### Claim 12 (depends on 1) A MEMS transducer as claimed in claim 1, wherein the, or each, path segment traces a path which comprises one or more curved sections. ### Claim 13 (depends on 1) A MEMS transducer as claimed in claim 1, wherein the, or each, path segment is provided in a region at the periphery of the flexible membrane. ### Claim 14 (depends on 1) A MEMS transducer as claimed in claim 1, wherein one of said first and second path points substantially coincides with the endpoint of the associated unbound edge. ### Claim 15 A MEMS transducer comprising a flexible membrane supported at a supporting edge relative to a substrate, the membrane comprising first and second unbound edges which each extend from an endpoint at, or near, first and second ends of the supporting edge respectively, a path segment being defined between first and second path points on each of the unbound edges, each path segment comprising at least two bendpoints at which the flexible membrane tends to bend in response to a given deflection of the flexible membrane, wherein a bendpoint of the first segment corresponds to a bendpoint of the second segment, said corresponding bendpoints forming a pair of bendpoints and wherein a line intersecting the pair of bendpoints defines a bend axis of the flexible membrane, wherein a first bend axis is substantially parallel to a second bend axis and also to the supporting edge. ### Claim 16 A MEMS transducer comprising a membrane having a first membrane region and a second membrane region, wherein the first membrane region is supported at a supporting edge relative to a substrate and comprises an active central region and a plurality of supporting arms, each supporting arm extending laterally from the central region, the first membrane region being separated from the second membrane region by one or more slits, a given slit providing an unbound edge portion of the support arm, wherein the unbound edge portion traces a path from an endpoint at or near the supporting edge, wherein a path segment is defined between said endpoint which forms a first path point and a second path point, wherein the path segment traces a non-linear path. ### Claim 17 (depends on 1) A MEMS transducer as claimed in claim 1 comprising a back-plate structure wherein the flexible membrane is supported with respect to said back-plate structure. ### Claim 18 (depends on 17) A MEMS transducer as claimed in claim 17 wherein said back-plate structure comprises a plurality of holes through the back-plate structure. ### Claim 19 (depends on 1) A MEMS transducer as claimed in claim 1, wherein the flexible membrane comprises a vent structure, the vent structure comprising a moveable portion which, in response to a differential pressure across the vent structure, deflects to reveal a flow path through the membrane. ### Claim 20 (depends on 1) A MEMS transducer as claimed in claim 1 wherein said transducer comprises a capacitive microphone. ### Claim 21 (depends on 1) An electronic device comprising a MEMS transducer as claimed in claim 1, wherein said device is at least one of: a portable device; a battery powered device; an audio device; a computing device; a communications device; a personal media player; a mobile telephone; a games device; and a voice controlled device.