# US 12,006,446 B2 · Polishing liquid and chemical mechanical polishing method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,006,446 B2 - Document ID: US12006446B2 - Status: Granted - Kind: B2 - Application number: 17/547,176 - Filed: 2021-12-09 - Published: 2022-03-31 - Granted: 2024-06-11 - Earliest claimed: 2019-06-20 - Assignees: FUJIFILM Corporation - Applicants: FUJIFILM Corporation - Inventors: Tetsuya Kamimura - Web page: https://patentgrep.com/patent/US12006446B2 ## CPC - C09G 1/02: containing abrasives or grinding agents {(abrasives as such C09K3/14; polishing of semi-conductors H10P52/40)} - B24B 37/00: Lapping machines or devices; Accessories (B24B3/00 takes precedence) - C09K 3/14: Anti-slip materials; Abrasives {(products specifically intended for the fabrication of abrasive tools, blocks or papers, or for operations of the kind of sand-blasting and barrelling B24B31/14, B24C1/00; polishing compositions containing abrasive or grinding agents C09G1/02; friction compositions for brakes or clutches F16D69/02; polishing of semi-conductors H10P52/40)} - H10P 52/403: {of conductive or resistive materials} - H10P 70/277: {the processing being a planarisation of conductive layers} - C09G: POLISHING COMPOSITIONS (French polish C09F11/00); SKI WAXES - B24B: MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING (grinding of gear teeth B23F, of screw-threads B23G1/36; by electro-erosion B23H; abrasive or related blasting B24C; tools for grinding, buffing or sharpening B24D; polishing compositions C09G1/00; abrasives C09K3/14; electrolytic etching or polishing C25F3/00; grinding arrangements for use on assembled railway tracks E01B31/17); DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract The present invention provides a polishing liquid which has a good polishing speed and reduces the occurrence of dishing on a surface to be polished of an object to be polished having a cobalt-containing film after polishing in a case where the polishing liquid is applied to CMP of the object to be polished, and makes it possible to manufacture a semiconductor product having excellent reliability. The present invention also provides a chemical mechanical polishing method using the polishing liquid. The polishing liquid of an embodiment of the present invention is a polishing liquid used for chemical mechanical polishing of an object to be polished having a cobalt-containing film, the polishing liquid including colloidal silica, one or more specific compounds selected from the group consisting of glycine, alanine, sarcosine, and iminodiacetic acid, a passivation film forming agent, hydrogen peroxide, sodium, and ammonia, in which a mass ratio of a content of ammonia to a content of sodium is 1×103 to 1×106, and a pH is 5.5 to 8.0. ## Claims ### Claim 1 A polishing liquid used for chemical mechanical polishing of an object to be polished having a cobalt-containing film, the polishing liquid comprising: colloidal silica; one or more specific compounds selected from the group consisting of glycine, alanine, sarcosine, and iminodiacetic acid; one or more passivation film forming agents selected from the group consisting of a compound represented by General Formula (1) and a compound represented by General Formula (2); hydrogen peroxide; sodium, wherein a content of sodium is 5 ppt to 250 ppt by mass with respect to a total mass of the polishing liquid; and ammonia, wherein a ClogP value of the passivation film forming agent is 1.0 or more, a mass ratio of a content of ammonia to the content of sodium is 1×103 to 1×106, and a pH is 5.5 to 8.0, in General Formula (1), R1 to R5 each independently represent a hydrogen atom or a substituent, and two adjacent groups in R1 to R5 may be bonded to each other to form a ring, and in General Formula (2), R6 to R10 each independently represent a hydrogen atom or a substituent, and two adjacent groups in R6 to R10 may be bonded to each other to form a ring. ### Claim 2 (depends on 1) The polishing liquid according to claim 1, further comprising an anionic surfactant. ### Claim 3 (depends on 2) The polishing liquid according to claim 2, wherein a value of a difference obtained by subtracting the ClogP value of the passivation film forming agent from the ClogP value of the anionic surfactant is more than 1.80 and less than 8.00. ### Claim 4 (depends on 2) The polishing liquid according to claim 2, wherein a mass ratio of a content of the passivation film fanning agent to a content of the anionic surfactant is more than 2.0 and less than 100. ### Claim 5 (depends on 2) The polishing liquid according to claim 2, wherein the anionic surfactant has one or more anionic groups selected from the group consisting of a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a phosphonic acid group, a sulfuric acid ester group, a phosphoric acid ester group, and a group which is a salt thereof. ### Claim 6 (depends on 1) The polishing liquid according to claim 1, wherein a mass ratio of a content of the specific compound to a content of the passivation film Ruining agent is 2.0 to 20. ### Claim 7 (depends on 1) The polishing liquid according to claim 1, wherein a corrosion potential of cobalt in the polishing liquid is −0.2 to 0.6 V. ### Claim 8 (depends on 1) The polishing liquid according to claim 1, wherein a content of the colloidal silica is 0.5% by mass or less with respect to a total mass of the polishing liquid, and an average primary particle diameter of the colloidal silica is 60 nm or less. ### Claim 9 (depends on 1) The polishing liquid according to claim 1, further comprising a benzotriazole compound. ### Claim 10 (depends on 1) The polishing liquid according to claim 1, wherein the ClogP value of the passivation film forming agent is 1.0 to 3.8. ### Claim 11 (depends on 1) The polishing liquid according to claim 1, further comprising an organic solvent in an amount of 0.05% to 5.0% by mass with respect to a total mass of the polishing liquid. ### Claim 12 (depends on 1) The polishing liquid according to claim 1, further comprising a nonionic surfactant. ### Claim 13 (depends on 12) The polishing liquid according to claim 12, wherein an HLB value of the nonionic surfactant is 8 to 15. ### Claim 14 (depends on 1) The polishing liquid according to claim 1, wherein the passivation film forming agent is one or more selected from the group consisting of 4-methylphthalic acid, 4-nitrophthalic acid, salicylic acid, 4-methylsalicylic acid, anthranilic acid, 4-methylbenzoic acid, 4-tert-butylbenzoic acid, 4-propylbenzoic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 6-hydroxy-2-naphthalenecarboxylic acid, 1-hydroxy-2-naphthalenecarboxylic acid, 3-hydroxy-2-naphthalenecarboxylic acid, quinaldic acid, 8-hydroxyquinoline, and 2-methyl-8-hydroxyquinoline. ### Claim 15 (depends on 1) The polishing liquid according to claim 1, wherein a concentration of solid contents is 5% by mass or more, and the polishing liquid is used after 3-times or more dilution on a mass basis. ### Claim 16 (depends on 1) A chemical mechanical polishing method comprising a step of obtaining an object to be polished, which has been polished, by bringing a surface to be polished of the object to be polished into contact with a polishing pad attached to a polishing platen while supplying the polishing liquid according to claim 1 to the polishing pad, and relatively moving the object to be polished and the polishing pad to polish the surface to be polished. ### Claim 17 (depends on 16) The chemical mechanical polishing method according to claim 16, wherein a polishing pressure is 0.5 to 3.0 psi. ### Claim 18 (depends on 16) The chemical mechanical polishing method according to claim 16, wherein a supply rate of the polishing liquid supplied to the polishing pad is 0.14 to 0.35 ml/(min·cm2). ### Claim 19 (depends on 16) The chemical mechanical polishing method according to claim 16, further comprising a step of cleaning the object to be polished, which has been polished, with an alkaline cleaning liquid after the step of obtaining the object to be polished, which has been polished. ### Claim 20 A polishing liquid used for chemical mechanical polishing of an object to be polished, the polishing liquid comprising: abrasive grains; one or more specific compounds selected from the group consisting of glycine, alanine, sarcosine, and iminodiacetic acid; one or more passivation film forming agents selected from the group consisting of a compound represented by General Formula (1) and a compound represented by General Formula (2); hydrogen peroxide; sodium, wherein a content of sodium is 5 ppt to 250 ppt by mass with respect to a total mass of the polishing liquid; and ammonia, wherein a ClogP value of the passivation film forming agent is 1.0 or more, a mass ratio of a content of ammonia to the content of sodium is 1×103 to 1×106, and a pH is 5.5 to 8.0, in General Formula (1), R1 to R5 each independently represent a hydrogen atom or a substituent, and two adjacent groups in R1 to R5 may be bonded to each other to form a ring, and in General Formula (2), R6 to R10 each independently represent a hydrogen atom or a substituent, and two adjacent groups in R6 to R10 may be bonded to each other to form a ring. ### Claim 21 (depends on 1) The polishing liquid according to claim 1, wherein the content of ammonia is 1.0×104 to 1.0×108 ppt by mass with respect to the total mass of the polishing liquid. ### Claim 22 (depends on 1) The polishing liquid according to claim 1, wherein the content of sodium is 56 ppt to 99 ppt by mass with respect to a total mass of the polishing liquid. ### Claim 23 (depends on 20) The polishing liquid according to claim 20, wherein the content of ammonia is 1.0×104 to 1.0×108 ppt by mass with respect to the total mass of the polishing liquid. ### Claim 24 (depends on 20) The polishing liquid according to claim 20, wherein the content of sodium is 56 ppt to 99 ppt by mass with respect to a total mass of the polishing liquid.