# US 7,407,885 B2 · Methods of forming electrically conductive plugs > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,407,885 B2 - Document ID: US7407885B2 - Status: Granted - Kind: B2 - Application number: 11/127,943 - Filed: 2005-05-11 - Published: 2006-11-16 - Granted: 2008-08-05 - Earliest claimed: 2005-05-11 - Assignees: Micron Technology, Inc. - Inventors: Zhaoli Sun; Jun Liu; Dapeng Wang - Web page: https://patentgrep.com/patent/US7407885B2 ## CPC - H10W 20/037: {the barrier, adhesion or liner layers being on top of a main fill metal} - H10N 70/011: {Manufacture or treatment of multistable switching devices} - H10N 70/245: {the species being metal cations, e.g. programmable metallization cells} - H10N 70/826: {adapted for essentially vertical current flow, e.g. sandwich or pillar type devices} - H10N 70/841: {Electrodes} - H10N 70/8825: {Selenides, e.g. GeSe} - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 - H10N: ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR ## Abstract A method of forming an electrically conductive plug includes providing an opening within electrically insulative material over a node location on a substrate. An electrically conductive material is formed within the opening and elevationally over the insulative material. Some of the conductive material is removed effective to recess an outermost surface of the conductive material to from about 100 Angstroms to about 200 Angstroms from an outermost surface of the insulative material after said removing of some of the conductive material. After removing some of the conductive material, remaining volume of the opening over the conductive material is overfilled with an electrically conductive metal material different from that of the conductive material. The metal material is polished effective to form an electrically conductive plug within the opening comprising the conductive material and the metal material. Other aspects and implementations are contemplated. ## Claims ### Claim 1 A method of forming an electrically conductive plug, comprising: providing an opening within electrically insulative material over a node location on a substrate; forming an electrically conductive material within the opening and elevationally over the insulative material; removing some of the conductive material effective to recess an outermost surface of the conductive material to from about 100 Angstroms to about 200 Angstroms from an outermost surface of the insulative material after said removing of some of the conductive material; after removing some of the conductive material, overfilling remaining volume of the opening over the conductive material with an electrically conductive metal material different from that of the conductive material, the overfilling depositing the electrically conductive metal material to be blanketly covering elevationally over all of the insulative material; and polishing the metal material effective to form an electrically conductive plug within the opening comprising the conductive material and the metal material. ### Claim 2 (depends on 1) The method of claim 1 wherein the conductive material comprises metal in elemental form. ### Claim 3 (depends on 2) The method of claim 2 wherein the elemental metal comprises tungsten. ### Claim 4 (depends on 2) The method of claim 2 wherein the elemental metal comprises an alloy of elemental metals. ### Claim 5 (depends on 1) The method of claim 1 wherein the conductive material comprises a conductive metal compound. ### Claim 6 (depends on 1) The method of claim 1 wherein the conductive material comprises conductively doped semiconductive material. ### Claim 7 (depends on 1) The method of claim 1 wherein removing some of the conductive material is effective to recess the outermost surface of the conductive material to from about 120 Angstroms to about 200 Angstroms from the outermost surface of the insulative material after said removing of some of the conductive material. ### Claim 8 (depends on 7) The method of claim 7 wherein removing some of the conductive material is effective to recess the outermost surface of the conductive material to from 155 Angstroms to 165 Angstroms from the outermost surface of the insulative material after said removing of some of the conductive material. ### Claim 9 (depends on 1) The method of claim 1 wherein the removing some of the conductive material and the polishing of the metal material comprise chemical mechanical polishing. ### Claim 10 (depends on 9) The method of claim 9 wherein said chemical mechanical polishings use the same composition polishing slurry. ### Claim 11 (depends on 1) The method of claim 1 wherein the metal material comprises a metal nitride. ### Claim 12 (depends on 11) The method of claim 11 wherein the metal nitride comprises at least one of TiN and WN. ### Claim 13 (depends on 12) The method of claim 12 wherein the conductive material comprises elemental tungsten. ### Claim 14 (depends on 1) The method of claim 1 wherein the conductive material comprises at least one of Cu, Pt, Ti, Ni, Co, Pd, Mo, Zr, Ta, and C in elemental or alloy form. ### Claim 15 (depends on 1) The method of claim 1 wherein the conductive material within the opening comprises a crevice after said removing some of the conductive material, the metal material filling the crevice. ### Claim 16 A method of forming electrically conductive plugs, comprising: providing a plurality of openings within electrically insulative material over respective node locations on a substrate; forming an electrically conductive material within the openings and elevationally over the insulative material; removing some of the conductive material effective to recess an outermost surface of the conductive material from an outermost surface of the insulative material after said removing of some of the conductive material, a crevice being received in the conductive material in at least some of the openings after said removing some of the conductive material; after removing some of the conductive material, overfilling remaining volume of the openings over the conductive material with an electrically conductive metal material different from that of the conductive material, and effective to fill the crevices; and polishing the metal material effective to form electrically conductive plugs within the openings comprising the conductive material and the metal material. ### Claim 17 (depends on 16) The method of claim 16 wherein the crevices have respective maximum open widths which are less than 50% of a minimum width of the respective opening in which the crevice is received. ### Claim 18 (depends on 16) The method of claim 16 wherein the crevices have respective maximum open widths which are less than 33% of a minimum width of the respective opening in which the crevice is received. ### Claim 19 (depends on 16) The method of claim 16 wherein the crevices have respective maximum open widths which are less than 25% of a minimum width of the respective opening in which the crevice is received. ### Claim 20 A method of forming a resistance variable element, comprising: providing an opening within electrically insulative material over a node location on a substrate; forming an electrically conductive material within the opening and elevationally over the insulative material; removing some of the conductive material effective to recess an outermost surface of the conductive material to from about 100 Angstroms to about 200 Angstroms from an outermost surface of the insulative material after said removing of some of the conductive material; after removing some of the conductive material, overfilling remaining volume of the opening over the conductive material with an electrically conductive metal material different from that of the conductive material, the overfilling depositing the electrically conductive metal material to be blanketly covering elevationally over all of the insulative material; polishing the metal material effective to form an electrically conductive plug within the opening comprising the conductive material and the metal material, the electrically conductive plug comprising a first electrode of a resistance variable element; forming a chalcogenide glass material over the first electrode; and forming a second electrode over the chalcogenide glass material. ### Claim 21 (depends on 16) The method of claim 16 wherein the crevices have respective maximum open widths which are less than 25% of a minimum width of the respective opening in which the crevice is received. ### Claim 22 (depends on 16) The method of claim 16 wherein removing some of the conductive material is effective to recess the outermost surface of the conductive material to from about 100 Angstroms to about 200 Angstroms from the outermost surface of the insulative material after said removing of some of the conductive material. ### Claim 23 (depends on 22) The method of claim 22 wherein removing some of the conductive material is effective to recess the outermost surface of the conductive material to from 120 Angstroms to about 200 Angstroms from the outermost surface of the insulative material after said removing of some of the conductive material. ### Claim 24 (depends on 16) The method of claim 16 wherein the conductive material has an outermost surface first roughness within the opening after removing some of the conductive material, and wherein the electrically conductive plug has an outermost surface second roughness after said metal material-polishing which is less than that of the first roughness. ### Claim 25 (depends on 24) The method of claim 24 wherein the first roughness is at least 4 nanometers RMS roughness, and the second roughness is no greater than 2 nanometers RMS roughness. ### Claim 26 (depends on 25) The method of claim 25 wherein the first roughness is at least 5 nanometers RMS roughness, and the second roughness is no greater than 1 nanometer RMS roughness. ### Claim 27 (depends on 16) The method of claim 16 wherein the conductive material comprises metal in elemental form. ### Claim 28 (depends on 27) The method of claim 27 wherein the elemental metal comprises tungsten. ### Claim 29 (depends on 16) The method of claim 16 wherein the conductive material comprises a conductive metal compound. ### Claim 30 (depends on 16) The method of claim 16 wherein the conductive material comprises conductively doped semiconductive material. ### Claim 31 (depends on 16) The method of claim 16 wherein the removing of some of the conductive material and the polishing of the metal material comprise chemical mechanical polishing. ### Claim 32 (depends on 31) The method of claim 31 wherein said chemical mechanical polishings use the same composition polishing slurry. ### Claim 33 (depends on 16) The method of claim 16 wherein the metal material comprises a metal nitride. ### Claim 34 (depends on 33) The method of claim 33 wherein the metal nitride comprises at least one of TiN and WN. ### Claim 35 (depends on 34) The method of claim 34 wherein the conductive material comprises elemental tungsten. ### Claim 36 (depends on 16) The method of claim 16 comprising a sealed void received within the conductive material prior to said removing, the crevice being formed by opening the sealed void in the conductive material by said removing. ### Claim 37 (depends on 16) The method of claim 16 wherein at least some of the openings comprise multiple crevices after said removing. ### Claim 38 (depends on 20) The method of claim 20 wherein the conductive material has an outermost surface first roughness within the opening after said removing of some of the conductive material, and wherein the electrically conductive plug has an outermost surface second roughness after said metal material-polishing which is less than that of the first roughness. ### Claim 39 (depends on 38) The method of claim 38 wherein the first roughness is at least 4 nanometers RMS roughness, and the second roughness is no greater than 2 nanometers RMS roughness. ### Claim 40 (depends on 39) The method of claim 39 wherein the first roughness is at least 5 nanometers RMS roughness, and the second roughness is no greater than 1 nanometer RMS roughness. ### Claim 41 (depends on 20) The method of claim 20 wherein the conductive material within the opening comprises a crevice after said removing some of the conductive material, the metal material filling the crevice. ### Claim 42 (depends on 20) The method of claim 20 wherein the removing of some of the conductive material and the polishing of the metal material comprise chemical mechanical polishing. ### Claim 43 (depends on 42) The method of claim 42 wherein said chemical mechanical polishings use the same composition polishing slurry.