# US 9,518,884 B2 · Micro-electro-mechanical device and method for making the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,518,884 B2 - Document ID: US9518884B2 - Status: Granted - Kind: B2 - Application number: 14/049,850 - Filed: 2013-10-09 - Published: 2014-04-24 - Granted: 2016-12-13 - Earliest claimed: 2012-10-22 - Assignees: Pixart Imaging Incorporation - Applicants: Ming-Han Tsai - Inventors: Ming-Han Tsai - Web page: https://patentgrep.com/patent/US9518884B2 ## CPC - G01L 11/04: by acoustic means - B81B 3/007: {For controlling stiffness, e.g. ribs} - G01L 9/0072: {using variations in capacitance} - H04R 19/00: Electrostatic transducers - H04R 19/005: {using semiconductor materials} - B81B 2201/0257: Microphones or microspeakers - H04R 2201/003: Mems transducers or their use - G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G) - B81B: MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES (piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/00, H10N35/00) - 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) ## Abstract The invention provides a micro-electro-mechanical device which includes a substrate, an electrode, and a diaphragm. The electrode includes plural vent holes. The diaphragm is disposed above and in parallel to the electrode, to form a capacitive sensor with the electrode. The diaphragm includes plural ribs protruding upward and/or downward from the diaphragm; the ribs are respectively disposed in correspondence to the plural vent holes and do not overlap nor contact the electrode. A method for making the micro-electro-mechanical device is also provided according to the present invention. ## Claims ### Claim 1 A micro-electro-mechanical device, comprising: a substrate, a first metal layer above the substrate, a via layer above the first metal layer, and a second metal layer above the via layer; an electrode, including a plurality of vent holes; and a diaphragm, including a planar layer and a plurality of ribs, wherein the planar layer is disposed above and in parallel to the electrode to form a capacitive sensor with the electrode, and the ribs protrude upward and/or downward from the planar layer such that the ribs are respectively disposed in correspondence to the vent holes, wherein the ribs are smaller than and within the vent holes from a top view having a direction normal to the substrate, such that the ribs do not contact the electrode and do not overlap the electrode from the top view; wherein each of the ribs at least includes the via layer and the second metal layer which are located in correspondence to the vent holes and are stacked such that a whole interface between the via layer and the second metal layer is in parallel to the planar layer, and the via layer and the second metal layer are different layers from the planar layer and do not belong to a part of the planar layer. ### Claim 2 (depends on 1) The micro-electro-mechanical device of claim 1, wherein the ribs are made of a conductive material including metal, metallic compound, conductive polymer, polysilicon or a combination thereof. ### Claim 3 (depends on 1) The micro-electro-mechanical device of claim 1, wherein the electrode includes a portion of the first metal layer and a portion of the substrate. ### Claim 4 (depends on 1) The micro-electro-mechanical device of claim 1, wherein the via layer is made of a conductive material and includes an internal space which is a hollow space or filled with a dielectric material. ### Claim 5 (depends on 1) The micro-electro-mechanical device of claim 1, wherein at least one of the ribs includes a bottom opening or a top opening. ### Claim 6 (depends on 1) The micro-electro-mechanical device of claim 1, wherein the ribs near a center region of the diaphragm have a relatively higher density than the ribs near a peripheral region of the diaphragm. ### Claim 7 (depends on 1) The micro-electro-mechanical device of claim 1, wherein the vent holes near a center region of the electrode have a relatively larger size than the vent holes near a peripheral region of the electrode. ### Claim 8 (depends on 1) The micro-electro-mechanical device of claim 1, further including a spacer to define an area of the diaphragm; and a supporting ring encompassing the diaphragm and disposed between a periphery of the diaphragm and the spacer. ### Claim 9 (depends on 8) The micro-electro-mechanical device of claim 8, wherein the supporting ring encompasses the diaphragm in a continuous form or the supporting ring encompasses the diaphragm with regular or irregular intervals. ### Claim 10 A method of making micro-electro-mechanical device, comprising: providing a substrate, a first metal layer above the substrate, a via layer above the first metal layer, and a second metal layer above the via layer; forming an electrode having a plurality of vent holes; forming a spacer on the substrate; and forming a diaphragm which includes a planar layer and a plurality of ribs, wherein the planar layer is connected to the spacer so that the diaphragm forms a capacitor sensor with the electrode, and the ribs protrude upward and/or downward from the planar layer such that the ribs are respectively disposed in correspondence to the vent holes, wherein the ribs are smaller than and within the vent holes from a top view having a direction normal to the substrate, such that the ribs do not contact the electrode and do not overlap the electrode from the top view; wherein each of the ribs at least includes the via layer and the second metal layer which are located in correspondence to the vent holes and are stacked such that a whole interface between the via layer and the second metal layer is in parallel to the planar layer, and the via layer and the second metal layer are different layers from the planar layer and do not belong to a part of the planar layer. ### Claim 11 (depends on 10) The method of claim 10, wherein the ribs are made of a conductive material including metal, metallic compound, conductive polymer, polysilicon, or a combination thereof. ### Claim 12 (depends on 10) The method of claim 10, wherein the electrode includes a portion of the first metal layer and a portion of the substrate. ### Claim 13 (depends on 10) The method of claim 10, wherein the via layer is made of a conductive material and includes an internal space which is a hollow space or filled with a dielectric material. ### Claim 14 (depends on 10) The method of claim 10, wherein at least one of the ribs includes a bottom opening or a top opening. ### Claim 15 (depends on 10) The method of claim 10, wherein the ribs near a center region of the diaphragm have a relatively higher density than the ribs near a peripheral region of the diaphragm. ### Claim 16 (depends on 10) The method of claim 10, wherein the vent holes near a center region of the electrode have a relatively larger size than the vent holes near a peripheral region of the electrode. ### Claim 17 (depends on 10) The method of claim 10, wherein the spacer defines an area of the diaphragm, and the method further comprises: forming a supporting ring encompassing the diaphragm and disposed between a periphery of the diaphragm and the spacer. ### Claim 18 (depends on 17) The method of claim 17, wherein the supporting ring encompasses the diaphragm in a continuous form or the supporting ring encompasses the diaphragm with regular or irregular intervals.