# US 2019/0169751 A1 · Process for depositing a metal or metal alloy on a surface of a substrate including its activation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0169751 A1 - Document ID: US20190169751A1 - Status: Published application - Kind: A1 - Application number: 16/092,459 - Filed: 2017-05-04 - Published: 2019-06-06 - Earliest claimed: 2016-05-04 - Assignees: Atotech Deutschland GmbH - Applicants: Atotech Deutschland GmbH - Inventors: Christian WENDELN; Lutz STAMP; Bexy DOSSE; Kay WURDINGER; Gerson KRILLES; Tang Cam Lai NGUYEN - Web page: https://patentgrep.com/patent/US20190169751A1 ## CPC - C23C 18/40: using reducing agents - C23C 18/1844: {with use of organic or inorganic compounds other than metals, first} - C23C 18/2066: {Use of organic or inorganic compounds other than metals, e.g. activation, sensitisation with polymers} - C23C 18/30: Activating {or accelerating or sensitising with palladium or other noble metal} - B05D 5/12: to obtain a coating with specific electrical properties - B05D 2350/00: Pretreatment of the substrate - C23C 18/1692: {Heat-treatment} - C23C 18/1893: {with use of organic or inorganic compounds other than metals, first} - C23C 18/24: using acid aqueous solutions - H05K 3/1208: {Pretreatment of the circuit board, e.g. modifying wetting properties; Patterning by using affinity patterns (providing shape patterns H05K3/1258; adhesion treatments H05K3/38)} - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - B05D: PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL (conveying articles or workpieces through baths of liquid B65G, e.g. B65G49/02) - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS ## Abstract A process for depositing metal or metal alloy on a substrate including treating the substrate surface with an activation solution comprising a source of metal ions so the metal ions are adsorbed on the substrate surface, treating the obtained substrate surface with a treatment solution containing an additive selected from thiols, thioethers, disulphides and sulphur containing heterocycles, and a reducing agent suitable to reduce the metal ions adsorbed on the substrate surface selected from boron based reducing agents, hypophosphite ions, hydrazine and hydrazine derivatives, ascorbic acid, iso-ascorbic acid, sources of formaldehyde, glyoxylic acid, sources of glyoxylic acid, glycolic acid, formic acid, sugars, and salts of aforementioned acids; and subsequently treating the substrate surface with a metallizing solution comprising a source of metal ions to be deposited such that a metal or metal alloy is deposited thereon. ## Claims ### Claim 1 A process for depositing a metal or metal alloy on at least one surface of a substrate comprising the steps of (a) providing a substrate; (b) treating the surface of said substrate with an activation solution comprising at least one source of metal ions selected from the group consisting of sources of ruthenium ions, sources of rhodium ions, sources of palladium ions, sources of osmium ions, sources of iridium ions, sources of platinum ions, sources of copper ions, sources of silver ions, sources of nickel ions, sources of cobalt ions, sources of gold ions and mixtures thereof such that at least one portion of said metal ions is being adsorbed on the surface of said substrate; (c) treating the surface of said substrate obtained from step (b) with a treatment solution comprising i) at least one additive independently selected from the group consisting of thiols, thioethers, disulphides and sulphur containing heterocycles, and ii) at least one reducing agent suitable to reduce the metal ions adsorbed on the surface of said substrate selected from the group consisting of boron based reducing agents, sources of hypophosphite ions, hydrazine and hydrazine derivatives, ascorbic acid, iso-ascorbic acid, sources of formaldehyde, glyoxylic acid, sources of glyoxylic acid, glycolic acid, formic acid, sugars, and salts of aforementioned acids; and (d) treating the surface obtained from step (c) of said substrate with a metallizing solution comprising a solvent and at least one source of metal ions to be deposited such that a metal or metal alloy is deposited thereon. ### Claim 2 (depends on 1) The process according to claim 1 characterised in that the at least one reducing agent is a boron based reducing agent selected from the group consisting of amino boranes, ammonia borane, borohydrides, borane and homologues thereof. ### Claim 3 (depends on 1) The process according to claim 1 characterised in that the concentration of the at least one reducing agent ranges from 0.1 to 500 mmol/L. ### Claim 4 (depends on 1) The process according to claim 1 characterised in that the metallizing solution is an electroless metallizing solution comprising said at least one source of metal ions, at least one complexing agents and at least one reducing agent. ### Claim 5 (depends on 4) The process according to claim 4 characterised in that the at least one source of metal ions in the metallizing solution is selected from the group consisting of sources of copper ions, of sources of nickel ions, of sources of cobalt ions and mixtures thereof. ### Claim 6 (canceled) ### Claim 7 (depends on 1) The process according to claim 1 characterised in that the at least one surface of the substrate is selected from the group consisting of metallic surfaces, non-metallic surfaces and combinations thereof. ### Claim 8 (depends on 1) The process according to claim 1 characterised in that the substrate is selected from the group consisting of printed circuit boards, printed circuit foils, interposers, chip carriers, IC substrates, semiconductor wafers, circuit carriers, interconnect devices and precursors for any of the aforementioned. ### Claim 9 (depends on 1) The process according to claim 1 characterised in that the additives selected from the group consisting of thiols, thioethers, disulphides and sulphur containing heterocycles are contained in the treatment solution in a total concentration of 0.1 μg/L to 1 g/L. ### Claim 10 (canceled) ### Claim 11 (canceled) ### Claim 12 (canceled) ### Claim 13 (depends on 1) The process according to claim 1 characterised in that the thiols are represented by the following formula (I) R1-SH (I) wherein R1 is independently selected from the group consisting of substituted and unsubstituted aliphatic groups, substituted and unsubstituted aryl groups and substituted and unsubstituted heteroaryl groups. ### Claim 14 (depends on 13) The process according to claim 13 characterised in that the thiols are selected from the group consisting of ethylthiol, 1-propylthiol, 2-propylthiol, 1-butylthiol, 2-butylthiol, 2-methylpropane-1-thiol, ethane-1,2-dithiol, propane-1,2-dithiol, propane-1,3-dithiol, butane-1,2-dithiol, butane-1,3-dithiol, butane-1,4-dithiol, butane-2,3-dithiol, 2-methylpropane-1,2-dithiol, 1H-benzo[d]imidazole-2-thiol, 1-methyl-1H-benzimidazole-2-thiol, 2-mercaptophenol, 4-mercaptophenol, thiosalicylic acid and 6-mercaptopyridine-3-carboxylic acid and the respective hydroxy and/or amino and/or carboxyl derivatives of the aforementioned. ### Claim 15 (depends on 1) The process according to claim 1 characterised in that the thioethers are represented by the following formula (II) R2-S—R3 (II) wherein R2 and R3 are independently from each other selected from the group consisting of substituted and unsubstituted aliphatic groups, substituted and unsubstituted aryl groups and substituted and unsubstituted heteroaryl groups. ### Claim 16 (depends on 15) The process according to claim 15 characterised in that the thioethers are selected from the group consisting of diethylsulphane, dipropylsulphane, dibutylsulphane, ethylproylsulphane, ethylbutylsulphane, propylbutylsulphane, 2(methylthio)benzoic acid, 4,4′-thiodiphenol, and the respective the respective hydroxy and/or amino and/or carboxyl derivatives of the aforementioned. ### Claim 17 (depends on 1) The process according to claim 1 characterised in that the disulphides are represented by the following formula (III) R4-S—S—R5 (III) wherein R4 and R5 are independently from each other selected from the group consisting of substituted and unsubstituted aliphatic groups, substituted and unsubstituted aryl groups and, substituted and unsubstituted heteroaryl groups. ### Claim 18 (depends on 17) The process according to claim 17 characterised in that the disulphides are selected from the group consisting of cystamine, 2-hydroxyethyl disulphide, 3-hydroxypropyldisulphide, 4-hydroxybutyldisulphide, dithiodiglycolic acid, 3,3′-dithiodipropionic acid, 4,4′-dithiodibutyric acid, bis(2-aminophenyl) disulphide, bis(4-aminophenyl) disulphide, 2,2′-dithiodibenzoic acid, difurfuryl disulphide, D-penicillamine disulphide, 3,3′-dihydroxydiphenyl disulphide, methyl furfuryl disulphide, 1,2-bis(2,2-diethoxyethyl)disulphide, 2,2′-dithiodipyridine and 6,6′-dithiodinicotinic acid. ### Claim 19 (depends on 1) The process according to claim 1 characterised in that the sulphur containing heterocycles comprise at least one ring-system which comprises carbon atoms, at least one sulphur atom and optionally at least one nitrogen atom, wherein the total amount of said carbon, sulphur and nitrogen atoms in the at least one ring-system ranges from 3 to 13 atoms, preferably from 4 to 12, more preferably from 5 to 9; and wherein the sulphur containing heterocycles are substituted or unsubstituted; and the sulphur containing heterocycles are saturated or unsaturated, preferably aromatic. ### Claim 20 (depends on 19) The process according to claim 19 characterised in that the sulphur containing heterocycles are selected from the group consisting of unsubstituted and substituted thiophene, unsubstituted and substituted thiazole, unsubstituted and substituted thiopyran, unsubstituted and substituted benzothiazole, unsubstituted and substituted thiabendazole, unsubstituted and substituted benzothiazole, unsubstituted and substituted thiazole, unsubstituted and substituted thiophene, unsubstituted and substituted tetrahydrothiophene, unsubstituted and substituted thiazolidine, unsubstituted and substituted 1,3-Dithiolane, unsubstituted and substituted 1,4-dithiane, unsubstituted and substituted 1,3-dithiane, unsubstituted and substituted thiomorpholine, unsubstituted and substituted tetrahydrothiopyran. ### Claim 21 (depends on 1) The process according to claim 1 characterised in that the treatment solution is free of intentionally added reducible metal ions. ### Claim 22 (canceled) ### Claim 23 (depends on 1) The process according to claim 1 characterised in that the at least one additive is a thioether.