# US 2001/0055874 A1 · Method for fabricating an array of ultra-small pores for chalcogenide memory cells > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2001/0055874 A1 - Document ID: US20010055874A1 - Status: Published application - Kind: A1 - Application number: 09/906,122 - Filed: 2001-07-16 - Published: 2001-12-27 - Earliest claimed: 1995-06-07 - Assignees: Micron Technology, Inc. - Inventors: Fernando Gonzalez; Raymond A. Turi - Web page: https://patentgrep.com/patent/US20010055874A1 ## CPC - H10N 70/068: {by processes specially adapted for achieving sub-lithographic dimensions, e.g. using spacers} - H10B 63/80: {Arrangements comprising multiple bistable or multi-stable switching components of the same type on a plane parallel to the substrate, e.g. cross-point arrays} - H10N 70/231: {based on solid-state phase change, e.g. between amorphous and crystalline phases, Ovshinsky effect} - H10N 70/826: {adapted for essentially vertical current flow, e.g. sandwich or pillar type devices} - H10N 70/8828: {Tellurides, e.g. GeSbTe} - Y10S 257/90: MOSFET type gate sidewall insulating spacer - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR - H10B: ELECTRONIC MEMORY DEVICES - Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS ## Abstract A method for fabricating an array of ultra-small pores for use in chalcogenide memory cells. A layer of a first material is applied onto a substrate. A portion of the layer of the first material is then removed to define an upper surface with vertical surfaces extending therefrom to a lower surface in the first layer of the first material. A fixed layer of a second material is then applied onto the vertical surfaces of the first layer of the first material. The fixed layer of the second material has a first thickness. A second layer of the first material is then applied onto the fixed layer of the second material. The fixed layer of the second material is then removed to define an array of pores in the first material layers. The pores thus defined have minimum lateral dimensions ranging from approximately 50 to 500 Angstroms and cross sectional areas greater than or equal to the first thickness of the second layer squared. The pores thus defined are further equally spaced from adjacent pores by a spacing ranging from approximately 0.25 to 0.5 microns. The pores thus defined may then be used to fabricate an array of chalcogenide memory cells. ## Claims ### Claim 1 A method of fabricating an array of pores, comprising the steps of: applying a first layer of a first material onto a substrate; removing a portion of said first layer of said first material to define an upper surface with generally vertical-surfaces extending therefrom to a lower surface in said first layer of said first material; applying a fixed layer of a second material onto said generally vertical surfaces of said first layer of said first material, said fixed layer of said second material having a first thickness; applying a second layer of said first material onto said fixed layer of said second material; and removing said fixed layer of said second material to define said array of pores in said first material layers. ### Claim 2 (depends on 1) The method of claim 1, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms. ### Claim 3 (depends on 1) The method of claim 1, wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared. ### Claim 4 (depends on 1) The method of claim 1, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms; and wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared. ### Claim 5 (depends on 1) The method of claim 1, wherein said upper surface is generally horizontal and includes a horizontal surface which is generally cross shaped. ### Claim 6 (depends on 5) The method of claim 5, wherein said cross shaped horizontal upper surface includes a pair of arms extending relative to a central point. ### Claim 7 (depends on 6) The method of claim 6, wherein said arms of said cross shaped horizontal upper surface range in length from about 0.5 to 1. microns. ### Claim 8 (depends on 1) The method of claim 1, wherein said upper surface is surrounded by a recess defined in part by said lower surface. ### Claim 9 (depends on 8) The method of claim 8, wherein said upper surface includes a plurality of arms extending laterally relative to a generally central location. ### Claim 10 (depends on 1) The method of claim 1, wherein said first material is comprised of silicon nitride. ### Claim 11 (depends on 1) The method of claim 1, wherein said second material is comprised of silicon dioxide. ### Claim 12 (depends on 1) The method of claim 1, wherein said first material is comprised of silicon nitride and wherein said second material is comprised of silicon dioxide. ### Claim 13 An array of pores fabricated by a process comprising the steps of: applying a first layer of a first material onto a substrate; removing a portion of said first layer of said first material to define an upper surface with generally vertical surfaces extending therefrom to a lower surface in said first layer of said first material; applying a fixed layer of a second material onto said generally vertical surfaces of said first layer of said first material, said fixed layer of said second material having a first thickness; applying a second layer of said first material onto said fixed layer of said second material; and removing said fixed layer of said second material to define said array of pores in said first material layers. ### Claim 14 (depends on 13) The array of pores of claim 13, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms. ### Claim 15 (depends on 13) The array of pores of claim 13, wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared. ### Claim 16 (depends on 13) The array of pores of claim 13, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms; and wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared. ### Claim 17 (depends on 13) The array of pores of claim 13, wherein said upper surface is generally horizontal and includes a horizontal surface which is generally cross shaped. ### Claim 18 (depends on 17) The array of pores of claim 17, wherein said cross shaped horizontal upper surface includes a pair of arms extending relative to a central point. ### Claim 19 (depends on 18) The array of pores of claim 18, wherein said arms of said cross shaped horizontal upper surface range in length from about 0.5 to 1 micron. ### Claim 20 (depends on 13) The array of pores of claim 13, wherein said upper surface is surrounded by a recess defined in part by said lower surface. ### Claim 21 (depends on 20) The array of pores of claim 20, wherein said upper surface includes a plurality of arms extending laterally relative to a generally central location. ### Claim 22 (depends on 13) The array of pores of claim 13, wherein said first material is comprised of silicon nitride. ### Claim 23 (depends on 13) The array of pores of claim 13, wherein said second material is comprised of silicon dioxide. ### Claim 24 (depends on 13) The array of pores of claim 13, wherein said first material is comprised of silicon nitride and wherein said second material is comprised of silicon dioxide. ### Claim 25 A chalcogenide memory cell, comprising: an upper electrode; a lower electrode; a dielectric layer positioned between said upper and lower electrodes and including an opening defining a pore; a chalcogenide element within said pore, said chalcogenide element electrically coupled to said upper and lower electrodes; wherein said pore has a minimum lateral dimension ranging from about 50 to 500 Angstroms. ### Claim 26 (depends on 25) The chalcogenide memory cell of claim 25, wherein said pore has an L shaped cross section. ### Claim 27 A method of fabricating an array of chalcogenide memory cells, comprising the steps of: applying a first layer of dielectric material onto a substrate that includes an array of conductive regions; removing a portion of said first layer of said dielectric material to define an upper surface with generally vertical surfaces extending therefrom to a lower surface in said first layer of said dielectric material; applying a fixed layer of a second material onto said generally vertical surfaces of said first layer of said dielectric material, said fixed layer of said second material having a first thickness; applying a second layer of said dielectric material onto said fixed layer of said second material; removing said fixed layer of said second material to define an array of pores in said dielectric material layers, said array of pores generally vertically aligned with said array of conductive regions of said substrate; and providing a chalcogenide memory cell at each of said pores by the steps comprising: applying a layer of chalcogenide material onto a region of said dielectric material layer generally centered at said pore, said layer of chalcogenide material extending into said pore; and applying a layer of conductive material onto said chalcogenide layer. ### Claim 28 (depends on 27) The method of claim 27, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms. ### Claim 29 (depends on 27) The method of claim 27, wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared. ### Claim 30 (depends on 27) The method of claim 27, wherein said pores have a minimum lateral dimension ranging from approximately 50 to 500 Angstroms; and wherein said pores have a cross sectional area greater than or equal to said first thickness of said layer of said second material squared. ### Claim 31 (depends on 27) The method of claim 27, wherein said upper surface is generally horizontal and includes a horizontal surface which is generally cross shaped. ### Claim 32 (depends on 31) The method of claim 31, wherein said cross shaped horizontal upper surface includes a pair of arms extending relative to a central point. ### Claim 33 (depends on 32) The method of claim 32, wherein said arms of said cross shaped horizontal upper surface range in length from about 0.5 to 1 micron. ### Claim 34 (depends on 27) The method of claim 27, wherein said upper surface is surrounded by a recess defined in part by said lower surface. ### Claim 35 (depends on 34) The method of claim 34, wherein said upper surface includes a plurality of arms extending laterally relative to a generally central location. ### Claim 36 An array of chalcogenide memory cells, comprising: a plurality of chalcogenide memory cells positioned in a generally common plane, each said chalcogenide memory cell including: an upper electrode; a lower electrode; a dielectric layer positioned between said upper and lower electrodes and including an opening defining a pore; a chalcogenide element within said pore, said chalcogenide element electrically coupled to said upper and lower electrodes; wherein pores of adjacent chalcogenide memory cells are spaced apart by a distance ranging from about 0.25 to 0.5 microns. ### Claim 37 (depends on 36) The array of claim 36, wherein a minimum lateral dimension of said pores ranges from about 50 to 500 Angstroms. ### Claim 38 (depends on 36) The array of claim 36, wherein each of said pores have an L shaped cross section.