# US 2014/0191371 A1 · Catalytic Etch With Magnetic Direction Control > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0191371 A1 - Document ID: US20140191371A1 - Status: Published application - Kind: A1 - Application number: 13/735,314 - Filed: 2013-01-07 - Published: 2014-07-10 - Earliest claimed: 2013-01-07 - Assignees: International Business Machines Corporation - Applicants: International Business Machines Corporation - Inventors: Eric A. Joseph; David W. Abraham; Roger W. Cheek; Alejandro G. Schroit; Ying Zhang - Web page: https://patentgrep.com/patent/US20140191371A1 ## CPC - H10P 50/692: {characterised by their composition, e.g. multilayer masks or materials} - H10D 62/117: {Shapes of semiconductor bodies} - H10D 62/83: being Group IV materials, e.g. B-doped Si or undoped Ge - H10P 50/242: {of Group IV materials} - H10P 50/268: {of silicon-containing layers} - H10P 50/642: {Chemical etching} - H10P 50/667: {by liquid etching only} - Y10T 428/24479: including variation in thickness - Y10T 428/24612: Composite web or sheet - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A material can be locally etched with arbitrary changes in the direction of the etch. A ferromagnetic-material-including catalytic particle is employed to etch the material. A wet etch chemical or a plasma condition can be employed in conjunction with the ferromagnetic-material-including catalytic particle to etch a material through a catalytic reaction between the catalytic particle and the material. During a catalytic etch process, a magnetic field is applied to the ferromagnetic-material-including catalytic particle to direct the movement of the particle to any direction, which is chosen so as to form a contiguous cavity having at least two cavity portions having different directions. The direction of the magnetic field can be controlled so as to form the contiguous cavity in a preplanned pattern, and each segment of the contiguous cavity can extend along an arbitrary direction. ## Claims ### Claim 1 A method of etching a material, said method comprising: disposing at least one ferromagnetic-material-including catalytic particle on a material; performing a catalytic etch process on said material by activating said at least one ferromagnetic-material-including catalytic particle with a chemical or a plasma; and changing a direction of propagation of said at least one ferromagnetic-material-including catalytic particle during said catalytic etch process by changing a direction of a gradient of a magnetic field applied to said at least one ferromagnetic-material-including catalytic particle. ### Claim 2 (depends on 1) The method of claim 1, wherein said direction of propagation of said at least one ferromagnetic-material-including catalytic particle is controlled to form a contiguous cavity including at least a first cavity portion extending along a first direction and a second cavity portion extending along a second direction, wherein said first direction and said second direction are different. ### Claim 3 (depends on 2) The method of claim 2, wherein said contiguous cavity includes a section in which a propagation direction of said contiguous cavity changes continuously. ### Claim 4 (depends on 2) The method of claim 2, wherein said contiguous cavity includes a third cavity portion extending along a third direction, wherein said first direction, said second direction, and said third direction are not within a same two-dimensional plane. ### Claim 5 (depends on 1) The method of claim 1, wherein said at least one ferromagnetic-material-including catalytic particle comprises: a ferromagnetic material core; and a surface coating over said ferromagnetic material core, said surface coating comprising a catalytic material that functions as a catalyst for said catalytic etch process. ### Claim 6 (depends on 1) The method of claim 1, wherein said at least one ferromagnetic-material-including catalytic particle consists of a ferromagnetic material that is a catalytic material that functions as a catalyst for said catalytic etch process. ### Claim 7 (depends on 1) The method of claim 1, wherein said catalytic etch process is a wet etch process employing a wet etch solution, wherein a surface of said at least one ferromagnetic-material-including catalytic particle is activated by said wet etch solution to etch said material. ### Claim 8 (depends on 1) The method of claim 1, wherein said catalytic etch process is a plasma etch process employing a plasma, wherein a surface of said at least one ferromagnetic-material-including catalytic particle is activated by said plasma to etch said material. ### Claim 9 A system for catalytically etching a material, said system comprising an apparatus containing: an etch chamber configured to perform a catalytic etch process of a material by activating at least one ferromagnetic-material-including catalytic particle; and a magnetic field generating apparatus configured to apply a non-uniform magnetic field to said at least one ferromagnetic-material-including catalytic particle within said etch chamber along at least two independent directions. ### Claim 10 (depends on 9) The system of claim 9, wherein said magnetic field generating apparatus is configured to change said magnetic field along at least three directions that are not within a same two-dimensional plane. ### Claim 11 (depends on 9) The system of claim 9, wherein said magnetic field generating apparatus is configured to contiguously change a direction of said magnetic field during operation of said catalytic etch process. ### Claim 12 (depends on 9) The system of claim 9, wherein said magnetic field generating apparatus is configured to align said magnetic field along an arbitrary spatial orientation within a three-dimensional polar coordinate system. ### Claim 13 (depends on 9) The system of claim 9, wherein said catalytic etch process is a wet etch process employing a wet etch solution, wherein a surface of said at least one ferromagnetic-material-including catalytic particle is activated by said wet etch solution to etch said material. ### Claim 14 (depends on 9) The system of claim 9, wherein said catalytic etch process is a plasma etch process employing a plasma, wherein a surface of said at least one ferromagnetic-material-including catalytic particle is activated by said plasma to etch said material. ### Claim 15 A patterned structure comprising: a substrate having a surface; and a plurality of contiguous cavities extending from said surface, wherein each of said plurality of contiguous cavities has a substantially same geometrical shape that including at least a first cavity portion extending along a first direction and a second cavity portion extending along a second direction, wherein said first direction and said second direction are different. ### Claim 16 (depends on 15) The patterned structure of claim 15, wherein each of said plurality of contiguous cavities includes a section in which a propagation direction of said each contiguous cavity changes continuously. ### Claim 17 (depends on 15) The patterned structure of claim 15, wherein each of said plurality of contiguous cavities includes a third cavity portion extending along a third direction, wherein said first direction, said second direction, and said third direction are not within a same two-dimensional plane. ### Claim 18 (depends on 15) The patterned structure of claim 15, wherein an angle between said first direction and said second direction is at least 90 degrees. ### Claim 19 (depends on 15) The patterned structure of claim 15, further comprising a material layer including a plurality of holes therein and covering said surface and containing a non-semiconductor material, wherein one end of each of said plurality of contiguous cavities coincides with one of said plurality of holes. ### Claim 20 (depends on 15) The patterned structure of claim 15, wherein a ferromagnetic-material-including catalytic particle is embedded within an end of each of said plurality of contiguous cavities.