# US 9,520,505 B2 · Capacitance type MEMS sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,520,505 B2 - Document ID: US9520505B2 - Status: Granted - Kind: B2 - Application number: 13/359,490 - Filed: 2012-01-26 - Published: 2012-08-02 - Granted: 2016-12-13 - Earliest claimed: 2011-01-27 - Assignees: Rohm Co., Ltd. - Applicants: Goro Nakatani - Inventors: Goro Nakatani - Web page: https://patentgrep.com/patent/US9520505B2 ## CPC - H10D 48/50: Devices controlled by mechanical forces, e.g. pressure - B81B 3/0021: {Transducers for transforming electrical into mechanical energy or vice versa (dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00)} - B81B 2201/0257: Microphones or microspeakers - B81B 2201/0292: Sensors not provided for in B81B2201/0207 - B81B2201/0285 - B81B 2203/0109: Bridges - B81B 2203/04: Electrodes - B81B 2203/051: Translation according to an axis parallel to the substrate - H04R 19/005: {using semiconductor materials} - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - 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 A capacitance type MEMS sensor has a first electrode portion and a second electrode portion facing each other. The sensor includes a semiconductor substrate having a recess dug in a thickness direction of the semiconductor substrate, the recess having sidewalls, one of which serves as the first electrode portion. The sensor further includes a diaphragm serving as the second electrode portion, the diaphragm arranged within the recess to face the first electrode portion in a posture extending along a depth direction of the recess, the diaphragm having a lower edge spaced apart from the bottom surface of the recess, and is made of the same material as the semiconductor substrate. The sensor further includes an insulating film arranged to join the diaphragm to the semiconductor substrate. ## Claims ### Claim 1 A capacitance type MEMS sensor, comprising: a first electrode portion; a second electrode portion facing the first electrode portion; and a semiconductor substrate having a recess dug in a thickness direction of the semiconductor substrate, the recess having sidewalls being a portion of the semiconductor substrate defining an inner surface of the recess, one of the sidewalls being the first electrode portion; wherein the second electrode portion is a diaphragm, the entire diaphragm arranged within the recess to be in parallel with and face the first electrode portion in a posture extending along a depth direction of the recess and to divide an internal space of the recess into a first space positioned at a side of the first electrode portion and a second space positioned at an opposite side of the first electrode portion, the diaphragm having a lower edge spaced apart from a bottom surface of the recess, the diaphragm being made of the same material as the semiconductor substrate; and wherein insulating films are arranged at longitudinal opposite sides of the diaphragm to join the longitudinal opposite sides of the diaphragm to the sidewalls other than the sidewall serving as the first electrode portion of the recess, the insulating films being interposed between the diaphragm and the sidewalls, and the insulating films electrically isolating the diaphragm from the semiconductor substrate. ### Claim 2 (depends on 1) The sensor of claim 1, further comprising a cover arranged on the semiconductor substrate to cover at least the first space. ### Claim 3 (depends on 1) The sensor of claim 1, further comprising: a cover arranged on the semiconductor substrate to cover the first space and the second space; and a bonding agent arranged to join the cover to the semiconductor substrate while leaving an opening through which the second space communicates with a space outside the recess. ### Claim 4 (depends on 1) The sensor of claim 1, further comprising a cover arranged on the semiconductor substrate to cover the first space and the second space, the cover having an opening through which the second space communicates with a space outside the recess. ### Claim 5 (depends on 1) The sensor of claim 1, further comprising a projection protruding toward the first electrode portion from a surface of the diaphragm facing the first electrode portion. ### Claim 6 (depends on 1) The sensor of claim 1, wherein the diaphragm includes an irregularity formed on a surface thereof facing the first electrode portion. ### Claim 7 (depends on 1) The sensor of claim 1, wherein the first electrode portion includes an irregularity formed on a surface thereof. ### Claim 8 (depends on 7) The sensor of claim 7, wherein the diaphragm includes a prominent portion and a depressed portion formed on a surface thereof facing the first electrode portion, the first electrode portion including a prominent portion and a depressed portion formed on a surface thereof facing the diaphragm, the prominent portion of the diaphragm inserted into the depressed portion of the first electrode portion, the prominent portion of the first electrode portion inserted into the depressed portion of the diaphragm. ### Claim 9 (depends on 1) The sensor of claim 1, further comprising an integrated circuit element formed in the semiconductor substrate. ### Claim 10 (depends on 1) The sensor of claim 1, wherein the sensor is a capacitance type microphone that uses the diaphragm as a vibrating plate.