Composition for selectively removing oxide compounds and etch residues of one or both of Co and Cu

Abstract

A composition for selectively removing an oxide compound of Co and Cu and an etch residue in the presence of one or more of Co, Cu, W, Ru and Mo is described, use of the composition for selectively removing oxide compounds of Co and Cu and etching residues in the presence of one or more of Co, Cu, W, Ru and Mo in a method for manufacturing a semiconductor device, and a method for manufacturing a semiconductor device, the method includes the step of selectively removing an oxide compound of Co and Cu and an etch residue in the presence of one or more of Co, Cu, W, Ru, and Mo.

Description

[0001] Described are a composition for selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo, use of the composition for selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo in a method for manufacturing a semiconductor device, and a method for manufacturing a semiconductor device, the method comprising the step of selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo.

[0002] In semiconductor manufacturing, the International Technology Roadmap for Semiconductors defines the 7nm process as the MOSFET technology node following the 10nm node. It is based on FinFET (fin field-effect transistor) technology, a multi-gate MOSFET technology. 7nm and below IC process technologies are expected to offer significantly reduced power consumption, significantly improved switching performance, and higher density.

[0003] In sub-7nm IC process technologies, new materials such as cobalt (Co) and tungsten (W) have been introduced to achieve better performance in integrated circuits. However, these materials are sensitive to oxidation, which is difficult to control during wet cleaning. Consequently, during wet cleaning, when aqueous cleaning compositions are applied to remove oxide compounds and etch residues resulting from etching of one or both of Co and Cu, particularly dry etching, undesirable pit formation and pitting are often observed on interconnects containing cobalt. Furthermore, interconnects such as tungsten can be damaged when exposed to cleaning solutions, which significantly impacts the yield and quality of IC manufacturing processes.

[0004] US2020 / 0339523 A1 discloses a composition for selectively etching a layer comprising an aluminum compound in the presence of a low-k material layer and / or a layer comprising copper and / or cobalt. The composition comprises one or more etchants comprising a fluoride anion, preferably ammonium fluoride.

[0005] US2015 / 0159124 A1 discloses a cleaning composition for cleaning a semiconductor substrate subjected to plasma etching, the composition comprising:

[0006] 1) at least one redox agent;

[0007] 2) at least one first chelating agent, the first chelating agent being a polyaminopolycarboxylic acid;

[0008] 3) at least one second chelating agent different from the first chelating agent, the second chelating agent comprising at least two nitrogen-containing groups;

[0009] 4) at least one metal corrosion inhibitor which is a substituted or unsubstituted benzotriazole;

[0010] 5) at least one organic solvent selected from the group consisting of water-soluble alcohols, water-soluble ketones, water-soluble esters, and water-soluble ethers;

[0011] 6) Water; and

[0012] 7) Optionally, at least one pH adjuster, which is a base that does not contain metal ions

[0013] The pH of the composition is preferably between 6 and about 11.

[0014] US 2015 / 0159124 A1 does not show that the proposed cleaning composition is suitable for selectively removing oxide compounds and etching residues of one or both of Co and Cu, especially in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo.

[0015] US2017 / 0200601 A1 discloses an aqueous cleaning composition comprising at least one nonionic surfactant corrosion inhibitor, at least one etchant source, at least one passivating agent, water, optionally at least one organic solvent, optionally at least one buffer substance, optionally at least one additional corrosion inhibitor, and optionally at least one oxidizing agent, wherein the aqueous cleaning composition is suitable for cleaning post-plasma etch residues from microelectronic devices having the residues thereon. Preferably, the at least one etchant comprises a fluoride species selected from the group consisting of hydrofluoric acid, fluoroboric acid, tetramethylammonium hexafluorophosphate, ammonium fluoride, ammonium bifluoride, tetrabutylammonium tetrafluoroborate, tetramethylammonium tetrafluoroborate, tetraethylammonium tetrafluoroborate, tetrapropylammonium tetrafluoroborate, tetrabutylammonium tetrafluoroborate, tetramethylammonium tetrafluoroborate, tetraethylammonium tetrafluoroborate, tetrapropylammonium tetrafluoroborate, tetrabutylammonium tetrafluoroborate, and combinations thereof.

[0016] WO 2015 / 060954 A1 discloses a cleaning composition comprising

[0017] 1) at least one chelating agent, which is a polyaminopolycarboxylic acid;

[0018] 2) at least one organic solvent selected from the group consisting of water-soluble alcohols, water-soluble ketones, water-soluble esters, and water-soluble ethers;

[0019] 3) at least one monocarboxylic acid containing a primary or secondary amino group and at least one additional nitrogen-containing basic group;

[0020] 4) at least one metal corrosion inhibitor which is a substituted or unsubstituted benzotriazole; and

[0021] 5) Water.

[0022] EP 3 664 125 A1 discloses a liquid composition comprising tetrafluoroboric acid in an amount of 0.01 to 30% by mass, or boric acid and hydrogen fluoride in a (boric acid) / (hydrogen fluoride) ratio of (0.0001 to 5.0% by mass) / (0.005 to 5.0% by mass), and having a pH value of 0.0 to 4.0.

[0023] US2015 / 290765 A1 discloses a rinse liquid having a pH of 8 or higher and containing the following components (A) to (F):

[0024] (A) Tetramethylammonium hydroxide

[0025] (B) a diamine selected from the group consisting of ethylenediamine and 1,2-diaminopropane

[0026] (C) an organic acid selected from the group consisting of oxalic acid, citric acid, tartaric acid, malic acid and picoline acid

[0027] (D) Histidine or its derivatives

[0028] (E) at least one species selected from the group consisting of benzotriazole, imidazole, triazole, tetrazole and derivatives thereof

[0029] (F) Water.

[0030] There continues to be a need for cleaning compositions that can selectively remove oxide compounds and etch residues of one or both of Co and Cu, wherein the cleaning compositions have good compatibility with interconnects selected from the group consisting of metals Co, Cu, W, Ru, and Mo.

[0031] These and other objects are achieved by the compositions disclosed herein. The compositions for selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo comprise

[0032] (A) one or more compounds selected from the group consisting of benzotriazoles,

[0033] (B) one or more compounds not having a triazole structure, selected from the group consisting of compounds having one or more primary and secondary amine groups, with the proviso that when the compound has only one primary amine group, the compound has at least three carbon atoms,

[0034] (C) one or more compounds selected from the group consisting of carboxylic acids and chelating agents,

[0035] (D) one or more water-miscible organic solvents

[0036] (E) Water,

[0037] wherein the total concentration of the compounds containing fluorine-containing anions is 0.0008 wt% or less based on the total mass of the composition,

[0038] The composition has a pH of less than 6.

[0039] More specifically, the composition may comprise

[0040] (A) one or more compounds selected from the group consisting of benzotriazoles

[0041] (B) one or more compounds not having a triazole structure, selected from the group consisting of compounds having one or more primary and secondary amine groups, with the proviso that when the compound has only one primary amine group, the compound has at least three carbon atoms, and with the proviso that when the compound has more than one carboxyl group and more than one amino group, it further comprises a sulfur group.

[0042] (C) one or more compounds selected from the group consisting of carboxylic acids and chelating agents

[0043] (D) one or more water-miscible organic solvents

[0044] (E) Water.

[0045] Component (A) of the composition defined above consists of one or more compounds acting as corrosion inhibitors and selected from the group consisting of benzotriazoles including 1H-benzotriazole (unsubstituted benzotriazole) and substituted benzotriazoles.

[0046] Component (B) of the composition defined above consists of one or more compounds that act as corrosion inhibitors and do not have a triazole structure. The one or more compounds of component (B) are selected from the group consisting of compounds having one or more primary and secondary amine groups, with the proviso that when the compound has only one primary amine group, the compound has at least three carbon atoms, and with the proviso that when the compound has more than one carboxyl group and more than one amino group, it also contains sulfur.

[0047] Surprisingly, it has been found that the combination of one or more first corrosion inhibitors (selected from the group consisting of benzotriazoles (component (A) as defined above)) and one or more second corrosion inhibitors (selected from the group consisting of compounds having one or more primary and secondary amine groups) enables the simultaneous protection of interconnections of multiple metals selected from the group consisting of Co, Cu, W, Ru and Mo from damage during the removal of oxide compounds and etching residues of one or both of Co and Cu, with the proviso that when the compound has only one primary amine group, the compound has at least three carbon atoms and with the proviso that when the compound has more than one carboxyl group and more than one amino group, it also contains sulfur (component (B) as defined above).

[0048] The component (C) of the composition defined above is composed of one or more compounds, which serve as an etchant for removing one or both of the oxide compound and etching residue of Co and Cu. The compound of component (C) is selected from the group consisting of carboxylic acid and chelating agent. The compound of component (C) does not have a triazole structure and is not a polyaminocarboxylic acid. One or more of the compounds of component (C) can be selected from compounds with a primary amino group that do not fall under the definition of component (B). The polyaminocarboxylic acids disclosed in US2015 / 0159124A1 are not used as component (C). Preferably, component (C) is composed of a carboxylic acid without an amino group, more preferably composed of a carboxylic acid without a nitrogen-containing group.

[0049] Component (D) of the composition defined above consists of one or more organic solvents which are miscible with water at least in a 1:1 weight ratio at 20°C and ambient pressure.

[0050] In certain cases, the composition consists of ingredients (A), (B), (C), (D) and (E) as defined above.

[0051] The composition as defined above is a homogeneous (i.e., single-phase) liquid under standard conditions (298 K and 101.325 kPa) in which components (A), (B), and (C) are dissolved. The composition as described herein is not a chemical-mechanical polishing composition because it does not contain any solid abrasive. Unlike the compositions disclosed herein, the chemical-mechanical polishing composition is not a single-phase liquid.

[0052] Surprisingly, it has been found that a composition comprising or consisting of components (A), (B), (C), (D) and (E) as defined above meets the objects defined above.

[0053] Preferably, in the compositions described herein, the concentration of hydroxylamine is 0.1 wt% or less, preferably 0.05 wt% or less, most preferably 0.01 wt% or less, in each case based on the total mass of the composition. Most preferably, the concentration of hydroxylamine is so low that it is not analytically detectable in the composition.

[0054] More preferably, the compositions described herein do not contain any compounds that can act as redox agents, ie, compounds that can induce oxidation and reduction during semiconductor cleaning processes.

[0055] Preferably, in the composition as defined above, the acetic acid is selected from the group consisting of butanediaminetetraacetic acid, diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetrapropionic acid, triethylenetetraaminehexaacetic acid, 1,3-diamino-2-hydroxypropane-N,N,N',N'-tetraacetic acid, propylenediaminetetraacetic acid, ethylenediaminetetraacetic acid (EDTA), trans-1,2-diaminocyclohexanetetraacetic acid, ethylenediaminediacetic acid, ethylenediaminedipropionic acid, 1,6-hexamethylene-diamine-N,N,N' %, more preferably 0.001 % or less, in each case based on the total mass of the composition. Most preferably, the concentration of the polyamino-polycarboxylic acids is so low that they are not analytically detectable in the composition. Further preferably, in the composition as defined above, the total concentration of any polyamino-polycarboxylic acids (excluding cysteine) is 0.008 wt % or less, more preferably 0.005 wt % or less, most preferably 0.001 % or less, in each case based on the total mass of the composition. Most preferably, the total concentration of the polyamino-polycarboxylic acids is so low that they are not analytically detectable in the composition.

[0056] Preferably, in the composition as defined above, the total concentration of compounds comprising fluoride-containing anions is 0.0008 wt% or less, preferably 0.0005 wt% or less, more preferably 0.0001 wt% or less, in each case based on the total mass of the composition. More preferably, the composition as described herein is free of fluoride-containing anions. Most preferably, the concentration of fluoride-containing ingredients is so low that elemental fluorine is not analytically detectable in the composition.

[0057] In the composition as described herein, preferably, the total amount of ingredient (A) is in the range of 0.5% to 5% based on the sum of the mass of ingredients (A), (B), (C), (D) and (E).

[0058] In the composition as described herein, preferably, the total amount of ingredient (B) is in the range of 500 ppm to 2000 ppm based on the sum of the masses of ingredients (A), (B), (C), (D) and (E).

[0059] In the composition as described herein, preferably, the total amount of ingredient (C) is in the range of 0.01% to 0.1% based on the sum of the mass of ingredients (A), (B), (C), (D) and (E).

[0060] In the composition as described herein, preferably, the total amount of ingredient (D) is in the range of 5% to 20% based on the sum of the mass of ingredients (A), (B), (C), (D) and (E).

[0061] Most preferably, in the composition as defined above,

[0062] The total amount of ingredient (A) is in the range of 0.5% to 5%,

[0063] and

[0064] The total amount of component (B) is in the range of 500 ppm to 2000 ppm,

[0065] and

[0066] The total amount of component (C) is in the range of 0.01% to 0.1%,

[0067] and

[0068] The total amount of ingredient (D) is in the range of 5% to 20%,

[0069] In each case based on the sum of the masses of components (A), (B), (C), (D) and (E).

[0070] In the composition consisting of ingredients (A), (B), (C), (D) and (E) as defined above, the concentrations of ingredients (A), (B), (C) and (D) may be within the ranges defined above, with water (E) making up the balance.

[0071] Preferably, the one or more compounds of ingredient (A) acting as corrosion inhibitors are selected from the group consisting of

[0072] (i) Unsubstituted benzotriazole

[0073] and

[0074] (ii) one or two independently selected from C 1-4 Alkyl, amino-C 1-4 Benzotriazole substituted with a substituent selected from the group consisting of alkyl, phenyl, halogen, hydroxy, nitro and thiol.

[0075] Preferably, all compounds of ingredient (A) are selected from the group defined above.

[0076] More preferably, the one or more compounds of ingredient (A) acting as corrosion inhibitors are selected from the group consisting of 1H-benzotriazole (i.e., unsubstituted benzotriazole), 6-methyl-benzotriazole, 5-methyl-benzotriazole, 5,6-dimethyl-1H-benzotriazole, 1-hydroxybenzotriazole, 5-phenyl-benzotriazole, 5-nitro-benzotriazole, 2-(5-amino-pentyl)-benzotriazole, 5-nitro-1-phenyl-1H-benzotriazole and 5-halogenated benzotriazole (e.g., 5-chlorobenzotriazole).

[0077] Preferably, all compounds of ingredient (A) are selected from the preferred groups defined above.

[0078] Preferably, the one or more compounds of ingredient (B) acting as corrosion inhibitors are selected from the group consisting of

[0079] - 2-amino acids with three or more carbon atoms, such as histidine, including sulfur-containing amino acids such as cysteine

[0080] -2-amino acid dipeptides and tripeptides, such as glutathione

[0081] - disulfides of sulfur-containing 2-amino acids, such as cystine

[0082] - and a biguanide having formula (I)

[0083]

[0084] in

[0085] R 1 Choose from H, C 1-6-alkyl, phenyl, halogenated phenyl (e.g. chlorophenyl) and C 1-3 -alkylphenyl group

[0086] R 2 Choose from H, C 1-6 -alkyl, phenyl, halogenated phenyl (e.g. chlorophenyl), C 1-3 - a group consisting of an alkylphenyl group and a biguanidine group (I')

[0087]

[0088] in

[0089] R 1 Choose from H, C 1-6 -alkyl, phenyl, halogenated phenyl (e.g. chlorophenyl) and C 1-3 -alkylphenyl group, and R 3 It is a C1-C8 alkylene group.

[0090] In some cases, it is preferred that the biguanide as defined above is a biguanide having formula (II)

[0091]

[0092] Each R 1 Independently selected from H, C 1-6 -alkyl, phenyl, halogenated phenyl (preferably chlorophenyl) and C 1-3 Preferably, the two R 1 are the same.

[0093] A preferred example of a biguanide having formula (II) is chlorhexidine (ie, 1,1′-hexamethylenebis[5-(4-chlorophenyl)biguanide).

[0094] Preferably, all compounds of ingredient (B) are selected from the group defined above.

[0095] Particularly preferably, the one or more compounds of component (B) acting as corrosion inhibitors are selected from the group consisting of biguanides having formula (II) (e.g., chlorhexidine (i.e., 1,1'-hexamethylenebis[5-(4-chlorophenyl)biguanide), histidine, glutathione, cysteine, and cystine. Chlorhexidine (i.e., 1,1'-hexamethylenebis[5-(4-chlorophenyl)biguanide) is most preferred.

[0096] Preferably, all compounds of ingredient (B) are selected from the preferred groups defined above.

[0097] Preferably, the one or more compounds serving as component (C) of the etchant are selected from the group consisting of citric acid, oxalic acid, glycolic acid, lactic acid, ethylenediaminetetra(methylenephosphonic acid) (EDTMP), succinic acid, malonic acid, nitrilotriacetic acid, methanesulfonic acid, lactic acid, propionic acid, formic acid, acetic acid, sulfosalicylic acid, salicylic acid, ascorbic acid and glycine.

[0098] Preferably, all compounds of ingredient (C) are selected from the group defined above.

[0099] Preferably, ingredient (C) consists of a carboxylic acid without an amino group, more preferably a carboxylic acid without a nitrogen-containing group. Thus, in certain cases, diaminetetrakis(methylenephosphonic acid) (EDTMP), glycine and nitrilotriacetic acid are less preferred.

[0100] The one or more organic water-miscible solvents of ingredient (D) are preferably selected from the group consisting of ethanol, isopropanol, n-propanol, 1,4-butanediol, diethylene glycol butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, 4-methylmorpholine-4-oxide, trimethylamine-N-oxide, triethylamine-N-oxide, triethanolamine-N-oxide, pyridine-N-oxide, N-formylmorpholine, N-ethylmorpholine-N-oxide, N-ethylpyrrolidine-N-oxide, dimethyl sulfoxide, dipropyl sulfoxide, diethyl sulfoxide, methyl ethyl sulfoxide, diphenyl sulfoxide, methyl phenyl sulfoxide and 1,1'-dihydroxyphenyl sulfoxide.

[0101] Preferably, all solvents of ingredient (D) are selected from the group defined above.

[0102] In preferred compositions,

[0103] - one, more or all compounds of ingredient (A) are selected from the preferred groups disclosed above, and

[0104] - one, more or all compounds of ingredient (B) are selected from the preferred groups disclosed above, and

[0105] - one, more or all compounds of ingredient (C) are selected from the preferred groups disclosed above, and

[0106] - One, more or all solvents of component (D) are selected from the preferred groups disclosed above.

[0107] Preferably, the composition as described herein has a pH value of less than 6, preferably in the range of 2 to 5.5, more preferably in the range of 2 to 5, further preferably 2.5 to 4.5, most preferably 2.5 to 4, especially preferably 2.8 to 3.7, as measured by a pH meter at 25°C and 101.325 kPa.

[0108] According to the Purbai diagram, tungsten corrosion is more effectively prevented at an acidic pH within the above-mentioned preferred range compared to the higher pH range of the composition according to US 2015 / 0159124 A1.

[0109] Particularly preferred are compositions comprising or consisting of

[0110] (A) one or both of 1H-benzotriazole and 5-methyl-1H-benzotriazole, wherein the total amount of 1H-benzotriazole and 5-methyl-1H-benzotriazole is in the range of 0.5% to 5%

[0111] (B) one or both of histidine and chlorhexidine, wherein the total amount of histidine and chlorhexidine is in the range of 500 ppm to 2000 ppm

[0112] (C) one or both of lactic acid and glycolic acid, wherein the total amount of lactic acid and glycolic acid is in the range of 0.01% to 0.1%

[0113] (D) one or both of N-formylmorpholine and dimethylsulfoxide, wherein the total amount of N-formylmorpholine and dimethylsulfoxide is in the range of 5% to 20%

[0114] (E) Water

[0115] In each case based on the sum of the masses of components (A), (B), (C), (D) and (E).

[0116] Preferably, the composition has a pH in the range of 2 to 5, further preferably 2.5 to 4.5, most preferably 2.5 to 4, especially preferably 2.8 to 3.7 as measured by a pH meter at 25°C and 101.325 kPa.

[0117] According to another aspect, the present disclosure relates to the use of a composition as defined above for selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo in a method for manufacturing a semiconductor device. Preferably, the semiconductor device is manufactured by means of a sub-7 nm IC process technology as mentioned above. Preferably, the semiconductor device is or comprises an integrated circuit (IC).

[0118] With regard to specific and preferred compositions for the use defined above, reference is made to the disclosure provided above in the context of the description of the composition for selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo.

[0119] In the uses defined above, the oxide compound may comprise oxides of one or both of Cu and Co.

[0120] In the use defined above, the etch residue may comprise fluorides of one or both of Cu and Co. Such etch residues are typically formed in dry etching processes.

[0121] In the uses defined above, the semiconductor device may comprise one or more interconnects comprising one or both of Co and Cu.

[0122] In the uses defined above, the semiconductor device may comprise one or more interconnects comprising one or more of W, Ru and Mo.

[0123] In the use defined above, the semiconductor device may comprise one or more dielectric materials selected from the group consisting of poly-Si, SiO2 and Si3N4.

[0124] More specifically, in the use defined above, the semiconductor device may include

[0125] - one or more first interconnects comprising one or both of Co and Cu, and

[0126] - one or more second interconnects comprising one or more of W, Ru and Mo, and

[0127] - one or more dielectric materials selected from the group consisting of poly-Si, SiO2 and Si3N4.

[0128] According to another aspect, the present disclosure relates to a method for manufacturing a semiconductor device, comprising the step of selectively removing oxide compounds and etching residues of one or both of Co and Cu by applying a composition as defined above in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo. Preferably, the semiconductor device is or comprises an integrated circuit (IC).

[0129] With regard to specific and preferred compositions of the above-defined method, reference is made to the disclosure provided above in the context of the description of the compositions.

[0130] Preferably, the semiconductor device is manufactured by means of the IC process technology below 7 nm as mentioned above.

[0131] Typically, in the method defined above, the composition defined above is used to clean the surface of the semiconductor device or its precursor after the dry etching step. Thus, the method for manufacturing a semiconductor device as described herein may comprise the following steps:

[0132] - dry etching the surface of the semiconductor device or its precursor

[0133] - selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo by applying a composition as defined above to a surface subjected to dry etching.

[0134] In the above defined methods, the composition as defined above can be applied to the surface area of the semiconductor device to be cleaned in any suitable manner using any suitable means. For example, the composition can be applied by means of dipping (immersing the surface area of the semiconductor device to be cleaned in the composition), rinsing, or spraying. Typically, the cleaning step is followed by drying.

[0135] In the method defined above, the oxide compound may comprise an oxide of one or both of Cu and Co.

[0136] In the method defined above, the etch residue may comprise fluorides of one or both of Cu and Co. Such etch residues are typically formed in dry etching processes.

[0137] In the method defined above, the semiconductor device may comprise one or more interconnects comprising one or both of Co and Cu.

[0138] In the method defined above, the semiconductor device may include one or more interconnects comprising one or more of W, Ru and Mo.

[0139] In the method defined above, the semiconductor device may comprise one or more dielectric materials selected from the group consisting of poly-Si, SiO 2 and Si 3 N 4 .

[0140] More specifically, in the method defined above, the conductor device may comprise

[0141] - one or more first interconnects comprising one or both of Co and Cu, and

[0142] - one or more second interconnects comprising one or more of W, Ru and Mo, and

[0143] - one or more dielectric materials selected from the group consisting of poly-Si, SiO2 and Si3N4.

[0144] Particularly preferred methods according to the present disclosure include the step of selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo by applying a composition comprising or consisting of:

[0145] (A) one or both of 1H-benzotriazole and 5-methyl-1H-benzotriazole, wherein the total amount of 1H-benzotriazole and 5-methyl-1H-benzotriazole is in the range of 0.5% to 5%

[0146] (B) one or both of histidine and chlorhexidine, wherein the total amount of histidine and chlorhexidine is in the range of 500 ppm to 2000 ppm

[0147] (C) one or both of lactic acid and glycolic acid, wherein the total amount of lactic acid and glycolic acid is in the range of 0.01% to 0.1%

[0148] (D) one or both of N-formylmorpholine and dimethylsulfoxide, wherein the total amount of N-formylmorpholine and dimethylsulfoxide is in the range of 5% to 20%

[0149] (E) Water

[0150] In each case based on the sum of the masses of components (A), (B), (C), (D) and (E).

[0151] Preferably, the composition has a pH in the range of 2 to 5, further preferably 2.5 to 4.5, most preferably 2.5 to 4, especially preferably 2.8 to 3.7 as measured by a pH meter at 25°C and 101.325 kPa.

[0152] According to another aspect, the present disclosure relates to the use of a biguanide according to formula (I) as defined above, preferably a biguanide according to formula (II) as defined above, as a corrosion inhibitor for inhibiting the corrosion of tungsten. Preferably, the biguanide is chlorhexidine (i.e., 1,1'-hexamethylenebis[5-(4-chlorophenyl)biguanide]. Surprisingly, it has been found that such biguanides, which have hitherto been primarily used for pharmaceutical applications (like chlorhexidine), are effective corrosion inhibitors for tungsten. Preferably, the biguanide according to formula (I) as defined above is used in a composition as defined above and / or in a method as defined above for manufacturing a semiconductor device as defined above.

[0153] Examples

[0154] The following examples are intended to further illustrate the present invention without limiting its scope.

[0155] The composition as defined above and the comparative composition (see table below for details) were applied to a sample having

[0156] (i) a film composed of a metal selected from the group consisting of Co, Cu, W, Mo, Ti and Ru, or

[0157] (ii) by its oxide (CoO x) covered by Co, the corresponding oxide (CuO x ) covered with a Cu film

[0158] (iii) Non-metallic films composed of TEOS or TiN

[0159] Deposited in each case on a substrate made of Si

[0160] or

[0161] (iv) Application to bare Si substrate.

[0162] The composition was brought to a temperature of 40° C. and applied to the sample by means of spin washing.

[0163] In cases (i) and (ii), the etching rate was determined by measuring the thickness change as a function of etching time by means of XRF (X-ray fluorescence) analysis. In case (ii), the slope of the thickness reduction is steep as long as the oxide is etched, and the slope of the thickness reduction suddenly flattens when the oxide is removed and the metal surface is exposed.

[0164] In cases (iii) and (iv), the etching rate is determined by measuring the thickness change as a function of the etching time by means of ellipsometry.

[0165] Etch rates are given in Angstroms per minute (A / min).

[0166] In Tables 1-4, the concentrations of all ingredients are given in wt % except for those ingredients where it is explicitly stated that the concentration is given in ppm.

[0167] 1. Screening of suitable Co corrosion inhibitors

[0168] The goal of this series of tests was to identify an effective corrosion inhibitor for Co. The compositions indicated in Table 1 (not according to the invention) were applied to a film consisting of Co deposited on a substrate made of Si. The etching rate was determined as described above (case (i)). In the compositions, the etchant (C) was oxalic acid and the solvent (D) was N-formyl-morpholine (NFM) or dimethyl sulfoxide (DMSO). Each of the compositions #1-2 to #1-10 contained a heterocyclic compound having one or more N atoms in the heterocyclic ring, and its efficiency in inhibiting Co corrosion was tested. The comparative composition #1-1 did not contain a heterocyclic compound having one or more N atoms in the heterocyclic ring. The comparative composition #1-1 is a conventional cleaning composition for removing CoOx.

[0169] The lower the Co etch rate, the more effective the corrosion inhibitor. Table 1 shows that compounds selected from the group consisting of benzotriazoles are excellent Co corrosion inhibitors compared to other heterocyclic compounds containing one or more N atoms in the heterocyclic ring (imidazoles and thiazoles). Therefore, benzotriazole, 5-methyl-1H-benzotriazole and 5-chlorobenzotriazole are suitable candidates for component (A) of the composition defined above.

[0170] Table 1

[0171]

[0172]

[0173] 2. Screening of suitable CoOx etchants

[0174] The goal of this series of tests was to identify effective etchants for CoOx that were more selective for etching CoOx than for etching metallic Co. The compositions indicated in Table 2 (not according to the invention) were applied to a film consisting of Co deposited on a substrate made of Si, wherein the Co film was covered with CoOx. The etching rate was determined as described above (case (ii)). In the compositions, one or both of benzotriazole and 5-methyl-1H-benzotriazole served as corrosion inhibitors (A), and the solvent (D) was N-formyl-morpholine (NFM). Each of the compositions #2-2 to #2.11 contained a compound that was tested for its efficiency in selectively etching CoOx (as may be formed by dry etching of Co). The comparative composition #2-1 did not contain any compound that could act as an etchant.

[0175] Table 2

[0176]

[0177] Table 2 shows that glycolic acid and lactic acid are more selective for etching CoOx than metallic Co (compositions #2.6, 2.7, and 2.8). Therefore, glycolic acid and lactic acid are suitable candidates for component (C) of the composition defined above. In contrast, fluorine-containing etchants such as those used in the prior art (see US2020 / 0339523A1) are less selective for etching CoOx than metallic Co.

[0178] 3. Screening of suitable W corrosion inhibitors

[0179] The goal of this series of tests was to identify effective corrosion inhibitors for tungsten (W). The compositions indicated in Table 3a were applied to different films, each deposited on a substrate made of Si, or to the bare surface of a Si substrate (see Table 3b for details), and the etching rates were determined as described above (cases (i), (ii), (iii), (iv), respectively). In the compositions, the etchant (C) was glycolic acid and the solvent (D) was N-formylmorpholine (NFM). Each of the compositions #3-2 to #3-11 contained one or more compounds to be tested for their efficiency in inhibiting the corrosion of W. The comparative composition #3-1 did not contain any other corrosion inhibitor other than benzotriazole.

[0180] Table 3b shows that chlorhexidine, histidine, glutathione, cystine, and cysteine (compositions #3.2 to #3.7, and #3.9 to #3.11) are superior W corrosion inhibitors compared to cetyltrimethylammonium hydroxide (composition #3.8, not according to the invention).

[0181] Therefore, chlorhexidine, histidine, glutathione, cystine and cysteine are suitable candidates for ingredient (B) of the composition defined above.

[0182] For comparison, composition FE1 disclosed in US2015 / 0159124 A1 was also tested (see Table 4). Surprisingly, it has a relatively high etching rate for tungsten, which may be due to the alkaline pH>6. In addition, it is more effective for etching CuO than for metallic Cu. x The selectivity is significantly lower than that of the composition according to the invention.

[0183]

[0184]

[0185] Table 4

[0186]

Claims

1. A composition for selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo The composition comprises (A) one or more compounds selected from the group consisting of benzotriazoles, (B) one or more compounds not having a triazole structure, selected from the group consisting of compounds having one or more primary and secondary amine groups, with the proviso that when the compound has only one primary amine group, the compound has at least three carbon atoms, (C) one or more compounds selected from the group consisting of carboxylic acids and chelating agents, (D) one or more water-miscible organic solvents (E) Water, wherein the total concentration of the compounds containing fluorine-containing anions is 0.0008 wt% or less based on the total mass of the composition, The composition has a pH of less than 6.

2. The composition according to claim 1, wherein The total concentration of the compound containing a fluorine-containing anion is 0.0005 wt% or less, more preferably 0.0001 wt% or less, based on the total mass of the composition.

3. The composition according to claim 1 or 2, having a pH value in the range of 2 to 5.5, more preferably in the range of 2.5 to 4.

4. A composition according to any preceding claim, wherein The total amount of ingredient (A) is in the range of 0.5% to 5%, and / or The total amount of component (B) is in the range of 500 ppm to 2000 ppm, and / or The total amount of component (C) is in the range of 0.01% to 0.1%, and / or The total amount of ingredient (D) is in the range of 5% to 20%, In each case based on the sum of the masses of components (A), (B), (C), (D) and (E).

5. A composition according to any preceding claim, wherein The one or more compounds of ingredient (A) are selected from the group consisting of unsubstituted benzotriazole and one or two independently selected compounds selected from C 1-4 -alkyl, amino-C 1-4 - benzotriazole substituted with a substituent selected from the group consisting of alkyl, phenyl, halogen, hydroxy, nitro and thiol, The one or more compounds of component (A) are preferably selected from the group consisting of: 1H-benzotriazole, 6-methyl-benzotriazole, 5-methyl-benzotriazole, 5,6-dimethyl-1H-benzotriazole, 1-hydroxybenzotriazole, 5-phenyl-benzotriazole, 5-nitro-benzotriazole, 2-(5-amino-pentyl)-benzotriazole, 5-nitro-1-phenyl-1H-benzotriazole and 5-halogenated benzotriazole.

6. A composition according to any preceding claim, wherein The one or more compounds of ingredient (B) are selected from the group consisting of - 2-amino acids having three or more carbon atoms, -2-amino acid dipeptides and tripeptides, -Sulfur-containing 2-amino acid disulfides - and a biguanide having formula (I) in R 1 Choose from H, C 1-6 -alkyl, phenyl, chlorophenyl and C 1-3 -alkylphenyl group R 2 Choose from H, C 1-6 -alkyl, phenyl, halogenated phenyl, C 1-3 - a group consisting of an alkylphenyl group and a biguanide group (I') in R 1 Choose from H, C 1-6 -alkyl, phenyl, halophenyl and C 1-3 alkylphenyl groups, and R 3 Is C1-C8 alkylene Wherein the biguanide is preferably a biguanide having formula (II) Each R 1 Independently selected from H, C 1-6 -alkyl, phenyl, halophenyl and C 1-3 - a group consisting of alkylphenyl groups; The one or more compounds of component (B) are preferably selected from the group consisting of chlorhexidine, histidine, glutathione, cysteine and cystine.

7. A composition according to any preceding claim, wherein The one or more compounds of ingredient (C) are selected from the group consisting of citric acid, oxalic acid, glycolic acid, lactic acid, ethylenediaminetetra(methylenephosphonic acid) (EDTMP), succinic acid, malonic acid, nitrilotriacetic acid, methanesulfonic acid, lactic acid, propionic acid, formic acid, acetic acid, sulfosalicylic acid, salicylic acid, ascorbic acid and glycine.

8. A composition according to any preceding claim, wherein The one or more organic solvents (D) are selected from the group consisting of ethanol, isopropanol, n-propanol, 1,4-butanediol, diethylene glycol butyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, 4-methylmorpholine-4-oxide, trimethylamine-N-oxide, triethylamine-N-oxide, triethanolamine-N-oxide, pyridine-N-oxide, N-formyl-morpholine, N-ethylmorpholine-N-oxide, N-ethylpyrrolidine-N-oxide, dimethyl sulfoxide, dipropyl sulfoxide, diethyl sulfoxide, methyl ethyl-sulfoxide, diphenyl sulfoxide, methyl phenyl sulfoxide and 1,1'-dihydroxyphenyl sulfoxide.

9. A composition according to any preceding claim comprising (A) one or both of 1H-benzotriazole and 5-methyl-1H-benzotriazole, wherein the total amount of 1H-benzotriazole and 5-methyl-1H-benzotriazole is in the range of 0.5% to 5% (B) one or both of histidine and chlorhexidine, wherein the total amount of histidine and chlorhexidine is in the range of 500 ppm to 2000 ppm (C) one or both of lactic acid and glycolic acid, wherein the total amount of lactic acid and glycolic acid is in the range of 0.01% to 0.1% (D) one or both of N-formylmorpholine and dimethylsulfoxide, wherein the total amount of N-formylmorpholine and dimethylsulfoxide is in the range of 5% to 20% (E) Water In each case based on the sum of the masses of components (A), (B), (C), (D) and (E).

10. Use of a composition for selectively removing oxide compounds and etching residues of one or both of Co and Cu in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo according to any preceding claim in a method for manufacturing a semiconductor device, wherein Preferably, the semiconductor device is manufactured with the aid of sub-7 nm IC process technology.

11. A method for manufacturing a semiconductor device, the method comprising the following steps Oxide compounds and etching residues of one or both of Co and Cu are selectively removed in the presence of one or more metals selected from the group consisting of Co, Cu, W, Ru and Mo by applying the composition according to any one of claims 1 to 9.

12. The method according to claim 11, wherein The semiconductor device is manufactured with the aid of sub-7nm IC process technology.

13. The method according to any one of claims 11 and 12, wherein These oxide compounds include oxides of one or both of Cu and Co. and / or The etching residues contain fluorides of one or both of Cu and Co.

14. The method according to any one of claims 11 to 13, wherein The semiconductor device includes One or more interconnects comprising one or both of Co and Cu and / or One or more interconnects comprising one or more of W, Ru, and Mo and / or One or more materials selected from the group consisting of poly-Si, SiO2 and Si3N4.

15. Use of a biguanide according to formula (I) as defined in claim 6, preferably a biguanide according to formula (II) as defined in claim 6, as a corrosion inhibitor for inhibiting the corrosion of tungsten, in particular in a composition according to any one of claims 1 to 9 and / or in a method according to any one of claims 11 to 14.

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