# US 9,054,671 B2 · Tunable filter structures and design structures > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,054,671 B2 - Document ID: US9054671B2 - Status: Granted - Kind: B2 - Application number: 13/292,729 - Filed: 2011-11-09 - Published: 2013-05-09 - Granted: 2015-06-09 - Earliest claimed: 2011-11-09 - Assignees: International Business Machines Corporation - Applicants: James W. Adkisson; Panglijen Candra; Thomas J. Dunbar; Mark D. Jaffe; Robert K. Leidy; Anthony K. Stamper - Inventors: James W. Adkisson; Panglijen Candra; Thomas J. Dunbar; Mark D. Jaffe; Robert K. Leidy; Anthony K. Stamper - Web page: https://patentgrep.com/patent/US9054671B2 ## CPC - H03H 9/545: {including active elements} - H03H 9/0547: {consisting of a vertical arrangement (H03H9/0566 takes precedence)} - H03H 9/171: {implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type} - H03H 9/173: {Air-gaps} - H03H 9/56: Monolithic crystal filters - H03H 2009/02204: {operating on an additional circuit element, e.g. applying a tuning DC voltage to a passive circuit element connected to the resonator} - Y10T 29/42: Piezoelectric device making - H03H: IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS (waveguides, resonators, lines or other devices of the waveguide type H01P) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Tunable filter structures, methods of manufacture and design structures are disclosed. The method of forming a filter structure includes forming a piezoelectric resonance filter over a cavity structure. The forming of the piezoelectric resonance filter includes: forming an upper electrode on one side of a piezoelectric material; and forming a lower electrode on an opposing side of the piezoelectric material. The method further includes forming a micro-electro-mechanical structure (MEMS) cantilever beam at a location in which, upon actuation, makes contact with the piezoelectric resonance filter. ## Claims ### Claim 1 A method of forming a filter structure, comprising: forming a piezoelectric resonance filter over a cavity structure, wherein the forming comprises: forming an upper electrode on one side of a piezoelectric material; and forming a lower electrode on an opposing side of the piezoelectric material; forming a micro-electro-mechanical structure (MEMS) cantilever beam at a location in which, upon actuation, makes contact with the piezoelectric resonance filter; and forming an electrode in an insulator material, below the cavity and structured to apply an effective load to the MEMS cantilever beam. ### Claim 2 (depends on 1) The method of claim 1, wherein forming of the MEMS cantilever beam comprises forming a comb structure over the piezoelectric resonance filter. ### Claim 3 (depends on 2) The method of claim 2, wherein forming of the comb structure comprises forming a high resistive region on a plurality of fingers of the comb structure. ### Claim 4 (depends on 2) The method of claim 2, wherein a plurality of fingers of the comb structure are locked in contact with the piezoelectric resonance filter through stiction. ### Claim 5 (depends on 1) The method of claim 1, further comprising forming a loading bar on the upper electrode of the piezoelectric resonance filter, wherein the MEMS cantilever beam is formed at a location in which, upon actuation, makes contact with the loading bar. ### Claim 6 (depends on 5) The method of claim 5, wherein: the loading bar is formed by depositing a metal or metal alloy on the upper electrode; and the loading bar acts as an electrode to pull down the MEMS cantilever beam into contact with the piezoelectric resonance filter. ### Claim 7 (depends on 5) The method of claim 5, wherein: the loading bar is formed by depositing a dielectric material on the upper electrode; and the upper electrode acts as an electrode to pull down the MEMS cantilever beam into contact with the piezoelectric resonance filter. ### Claim 8 A method of forming a filter structure, comprising: forming a piezoelectric resonance filter over a cavity structure, wherein the forming comprises: forming an upper electrode on one side of a piezoelectric material; and forming a lower electrode on an opposing side of the piezoelectric material; and forming a micro-electro-mechanical structure (MEMS) cantilever beam at a location in which, upon actuation, makes contact with the piezoelectric resonance filter, wherein forming of the MEMS cantilever beam comprises forming a comb structure over the piezoelectric resonance filter, wherein forming of the comb structure comprises forming a high resistive region on a plurality of fingers of the comb structure, and wherein the high resistive region is formed of a different material than remaining portions of the comb structure. ### Claim 9 A method of forming a filter structure, comprising: forming a piezoelectric resonance filter over a cavity structure, wherein the forming comprises: forming an upper electrode on one side of a piezoelectric material; and forming a lower electrode on an opposing side of the piezoelectric material; and forming a micro-electro-mechanical structure (MEMS) cantilever beam at a location in which, upon actuation, makes contact with the piezoelectric resonance filter, wherein forming of the MEMS cantilever beam comprises forming a comb structure over the piezoelectric resonance filter, and forming of the comb structure comprises at least one of forming fingers of different materials and fingers of different lengths. ### Claim 10 A filter structure, comprising: a piezoelectric resonance filter formed over a cavity structure, wherein the piezoelectric resonance filter comprises: an upper electrode on one side of a piezoelectric material; and a lower electrode on an opposing side of the piezoelectric material; a micro-electro-mechanical structure (MEMS) cantilever beam fixed on one end to an insulator material and suspended over the piezoelectric resonance filter at a location in which, upon actuation, makes contact with the piezoelectric resonance filter, wherein the MEMS cantilever beam comprises a comb structure, the comb structure comprises a high resistive region on a plurality of fingers of the comb structure, and the high resistive region is formed of a different material than remaining portions of the comb structure. ### Claim 11 A filter structure, comprising: a piezoelectric resonance filter formed over a cavity structure, wherein the piezoelectric resonance filter comprises: an upper electrode on one side of a piezoelectric material; and a lower electrode on an opposing side of the piezoelectric material; a micro-electro-mechanical structure (MEMS) cantilever beam fixed on one end to an insulator material and suspended over the piezoelectric resonance filter at a location in which, upon actuation, makes contact with the piezoelectric resonance filter; the MEMS cantilever beam comprises a comb structure, and an electrode in an insulator material, below the cavity and structured to apply an effective load to the MEMS cantilever beam. ### Claim 12 (depends on 11) The filter structure of claim 11, wherein the comb structure comprises a high resistive region on a plurality of fingers of the comb structure. ### Claim 13 (depends on 11) The filter structure of claim 11, wherein a plurality of fingers of the comb structure are locked in contact with the piezoelectric resonance filter through stiction. ### Claim 14 (depends on 11) The filter structure of claim 11, further comprising a loading bar on the upper electrode of the piezoelectric resonance filter, wherein the MEMS cantilever beam is at a location in which, upon actuation, makes contact with the loading bar, and wherein one of: the loading bar is a dielectric material and the upper electrode is structured to act as an electrode to pull down the MEMS cantilever beam into contact with the loading bar; and the loading bar is a metal or metal alloy, and is structured to act as an electrode to pull down the MEMS cantilever beam into contact with the loading bar. ### Claim 15 A filter structure, comprising: a piezoelectric resonance filter formed over a cavity structure, wherein the piezoelectric resonance filter comprises: an upper electrode on one side of a piezoelectric material; and a lower electrode on an opposing side of the piezoelectric material; and a micro-electro-mechanical structure (MEMS) cantilever beam fixed on one end to an insulator material and suspended over the piezoelectric resonance filter at a location in which, upon actuation, makes contact with the piezoelectric resonance filter, wherein the MEMS cantilever beam comprises a comb structure and the comb structure includes fingers of different lengths. ### Claim 16 A filter structure, comprising: a piezoelectric resonance filter formed over a cavity structure, wherein the piezoelectric resonance filter comprises: an upper electrode on one side of a piezoelectric material; and a lower electrode on an opposing side of the piezoelectric material; and a micro-electro-mechanical structure (MEMS) cantilever beam fixed on one end to an insulator material and suspended over the piezoelectric resonance filter at a location in which, upon actuation, makes contact with the piezoelectric resonance filter, wherein the MEMS cantilever beam comprises a comb structure and the comb structure includes fingers of different materials.