# US 9,434,607 B2 · MEMS device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,434,607 B2 - Document ID: US9434607B2 - Status: Granted - Kind: B2 - Application number: 14/660,157 - Filed: 2015-03-17 - Published: 2015-09-24 - Granted: 2016-09-06 - Earliest claimed: 2014-03-24 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Takahiko Yoshizawa - Web page: https://patentgrep.com/patent/US9434607B2 ## CPC - B81C 1/00246: {Monolithic integration, i.e. micromechanical structure and electronic processing unit are integrated on the same substrate} - B81B 2201/0271: Resonators; ultrasonic resonators - B81C 2203/0136: Growing or depositing of a covering layer - B81C 2203/0163: Reinforcing a cap, e.g. with ribs - B81C 2203/0764: Forming the micromechanical structure in a groove - 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) - B81B: MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES (piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/00, H10N35/00) ## Abstract A MEMS device includes a semiconductor substrate having a main surface with a first region in which a trench is formed and a second region in which an impurity diffusion region of a semiconductor circuit element is formed; a functional element provided, either directly or via an insulating film, on a bottom surface of the trench of the semiconductor substrate; a wall portion in the trench of the semiconductor substrate and forming a cavity surrounding the functional element; a lid portion that covers the cavity; and a pillar in the cavity and in contact with either the bottom surface of the trench of the semiconductor substrate or the insulating film, and with a back surface of the lid portion. ## Claims ### Claim 1 A MEMS device, comprising: a semiconductor substrate having a main surface with a first region in which a trench is formed and a second region in which an impurity diffusion region of a semiconductor circuit element is formed; a functional element provided, either directly or via an insulating film, on a bottom surface of the trench of the semiconductor substrate; a wall portion in the trench of the semiconductor substrate and forming a cavity surrounding the functional element; a lid portion that covers the cavity and includes a front surface and an edge between a top surface and a back surface defined by a thickness of the lid portion, wherein the back surface is a bottom surface of the lid portion facing the bottom surface of the trench; and a plurality of pillars in the cavity that are separated from the wall portion and in contact with either the bottom surface of the trench of the semiconductor substrate or the insulating film, and with the back surface of the lid portion. ### Claim 2 (depends on 1) The MEMS device according to claim 1, further comprising: an insulating layer that covers the main surface of the semiconductor substrate, the insulating layer provided with the lid portion and the semiconductor circuit element. ### Claim 3 (depends on 2) The MEMS device according to claim 2, wherein a surface of the insulating layer on the lid portion is treated by Chemical Mechanical Polishing (CMP). ### Claim 4 (depends on 1) The MEMS device according to claim 1, wherein the pillar is in contact with a central part of the back surface of the lid portion. ### Claim 5 (depends on 1) The MEMS device according to claim 1, wherein at least a part of the functional element constitutes the pillar. ### Claim 6 (depends on 1) The MEMS device according to claim 1, wherein the pillar is constructed integrally with the wall portion. ### Claim 7 (depends on 1) The MEMS device according to claim 1, wherein the pillar is in a central part between the functional element and the wall portion. ### Claim 8 (depends on 1) The MEMS device according to claim 1, wherein the pillar is configured to operate as an external connection electrode that is electrically connected to the functional element. ### Claim 9 (depends on 1) The MEMS device according to claim 1, wherein the functional element is provided directly on the bottom surface of the trench of the semiconductor substrate. ### Claim 10 (depends on 1) The MEMS device according to claim 1, wherein the functional element is provided on the bottom surface of the trench of the semiconductor substrate via an insulating film. ### Claim 11 (depends on 1) The MEMS device according to claim 1, wherein the functional element comprises one of a resonator, a sensor or an actuator. ### Claim 12 (depends on 1) The MEMS device according to claim 1, wherein the functional element and the semiconductor circuit element are integrated on the semiconductor substrate. ### Claim 13 (depends on 1) The MEMS device according to claim 1, wherein the lid portion includes an opening formed therein. ### Claim 14 (depends on 1) The MEMS device according to claim 1, wherein the lid portion is a planar layer with the pillar in contact with the back surface of the planar layer. ### Claim 15 (depends on 1) The MEMS device according to claim 1, wherein a portion of the back surface of the lid portion extends along a top portion of the pillar and is configured to support a portion of the lid portion from deformation. ### Claim 16 A MEMS device, comprising: a semiconductor substrate having a main surface with a first region in which a trench is formed and a second region in which an impurity diffusion region of a semiconductor circuit element is formed; a functional element on a bottom surface of the trench of the semiconductor substrate, the functional element including a lower electrode and an upper electrode; a wall portion in the trench of the semiconductor substrate and forming a cavity surrounding the functional element; a lid portion that covers the cavity and is separated from the functional element by a gap, the lid portion including a front surface and an edge between a top surface and a back surface defined by a thickness of the lid portion, wherein the back surface is a bottom surface of the lid portion facing the bottom surface of the trench; and a plurality of pillars in the cavity that are separated from the wall portion and in contact with the bottom surface of the trench of the semiconductor substrate, with the lower electrode of the functional element and with the back surface of the lid portion.