Cleaning composition containing molybdenum etch inhibitor

Abstract

The present disclosure relates to a removal composition for at least partially removing post-chemical mechanical polishing (post-CMP) residues from a surface of a microelectronic device. The removal composition includes an aqueous base composition and various molybdenum etch inhibitors that reduce the amount of molybdenum removed from the surface of the microelectronic device as compared to the aqueous base composition.

Description

Technical Field

[0001] The present disclosure relates to removal compositions for at least partially removing post-chemical mechanical polishing (post-CMP) residues from the surface of a microelectronic device. The removal compositions include an aqueous alkaline composition and various platinum etch inhibitors that reduce the amount of platinum removed from the surface of the microelectronic device compared to the aqueous alkaline composition. Background Art

[0002] Microelectronic device wafers are used to form integrated circuits and include a substrate, such as silicon, on which areas are patterned for the deposition of different materials having insulating, conductive or semiconductive properties. In order to obtain the correct pattern, excess material used to form the layers on the substrate must be removed. In addition, in order to manufacture functional and reliable circuits, it is important to prepare a flat or planar microelectronic wafer surface prior to subsequent processing. Therefore, it is necessary to remove and / or polish certain surfaces of the microelectronic device wafer.

[0003] Chemical mechanical polishing or planarization ("CMP") is a process that physically and chemically removes material from the surface of a microelectronic device wafer. The surface is polished (more specifically, planarized) by coupling a physical process such as abrasion with a chemical process such as oxidation or chelation. In its most basic form, CMP involves applying a slurry (e.g., a dispersion of an abrasive and an active chemical) to a polishing pad that polishes the surface of the microelectronic device wafer to achieve the removal, planarization, and polishing processes. It is not desirable for the removal or polishing process to consist of purely physical or purely chemical action, but rather a synergistic combination of the two to achieve rapid and uniform removal.

[0004] After CMP processing, particles, residues and other contaminants may be present on the surface of a microelectronic device. For this reason, post-CMP removal compositions have been developed to remove post-CMP residues, particles and contaminants that may interfere with subsequent device processing steps. However, these post-CMP removal compositions often unintentionally remove at least partially other materials that should have been retained from the device surface.

[0005] For example, as semiconductor devices become more highly integrated and miniaturized, molybdenum films are gaining more attention as potential new metal electrodes for next-generation semiconductor devices. However, during typical post-CMP removal processes, the removal composition also typically removes an unacceptable amount of molybdenum from the surface, which can cause malfunctions and pattern defects. The higher the pH of the removal composition, the more significant this problem is.

[0006] Therefore, new additives are needed to suppress Mo corrosion (lower etch rate and lower roughness) while adequately cleaning dielectric substrates (PETEOS, SiO2, thermal oxide, silicon nitride, silicon, etc.) for post-CMP cleaning.

[0007]

[0006] Therefore, there remains a need in the art for a high pH aqueous removal composition that can effectively remove post-CMP residues from the surface of a microelectronic device while inhibiting the removal of molybdenum from the device. Summary of the invention

[0008] In one embodiment, the present disclosure is directed to a removal composition for removing post-CMP residues from a surface of a microelectronic device. The removal composition comprises an aqueous alkaline composition having a pH greater than 10, the aqueous alkaline composition comprising water and at least one of: an organic additive, a cleaning additive, an organic solvent miscible with water, and a pH adjuster. The removal composition further comprises at least one molybdenum etch inhibitor selected from the group consisting of:

[0009] a) quaternary ammonium compounds of formula A:

[0010] Ar-RN + (R 1 )(R 2 )(R 3 )X - (A)

[0011] wherein Ar is a substituted or unsubstituted aryl group and X - is a hydroxyl ion, a halide ion, a sulfate ion or a methanesulfonate ion, and wherein:

[0012] 1) R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of them is C4-C 20 alkyl,

[0013] 2) R is C3-C 20 Alkylene and R 1 , R 2 and R 3 is methyl or ethyl, or

[0014] 3) R is C1-C 20 Alkylene, R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of contains a diol group,

[0015] b) quaternary ammonium compounds of formula B:

[0016] (R4 )(R 5 )(R 6 )(R 7 )N + X - (B)

[0017] Where R 4 , R 5 , R 6 and R 7 is a straight chain or branched chain alkyl group and R 4 , R 5 , R 6 and R 7 At least two of them are C6-C 20 alkyl,

[0018] c) a pyridinium compound of formula C or a bipyridinium compound of formula D:

[0019] R 9 -(C5H5N + )-R 8 X - (C)

[0020] R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (D)

[0021] Where R 8 is an alkyl group and R 9 is a substituted or unsubstituted straight chain or branched chain alkyl or alkylene group, and

[0022] d) A free radical scavenger selected from the group consisting of hydroxybenzene, pyrazolone, a compound having a nitroxide free radical, gluconolactone, a tertiary alkyl alcohol and ascorbic acid.

[0023] The removal composition removes less molybdenum from the surface of a microelectronic device comprising molybdenum than an aqueous alkaline composition.

[0024] In another embodiment, the present disclosure is directed to a method for removing post-CMP residues from the surface of a microelectronic device comprising a platinum material. The method comprises contacting the surface of the microelectronic device with a removal composition and at least partially removing the post-CMP residues from the surface of the microelectronic device. The removal composition comprises an aqueous alkaline composition having a pH greater than 10, the aqueous alkaline composition comprising water and at least one of the following: an organic additive, a cleaning additive, an organic solvent miscible with water, and a pH adjuster. The removal composition further comprises at least one platinum etching inhibitor selected from the group consisting of:

[0025] a) quaternary ammonium compounds of formula A:

[0026] Ar-RN + (R 1 )(R 2 )(R 3 )X - (A)

[0027] wherein Ar is a substituted or unsubstituted aryl group and X - is a hydroxyl ion, a halide ion, a sulfate ion or a methanesulfonate ion, and wherein:

[0028] 1) R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of them is C4-C 20 alkyl,

[0029] 2) R is C3-C 20 Alkylene and R 1 , R 2 and R 3 is methyl or ethyl, or

[0030] 3) R is C1-C 20 Alkylene, R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of contains a diol group,

[0031] b) quaternary ammonium compounds of formula B:

[0032] (R 4 )(R 5 )(R 6 )(R 7 )N + X - (B)

[0033] Where R 4 , R 5 , R 6 and R 7 is a straight chain or branched chain alkyl group and R 4 , R 5 , R 6 and R 7 At least two of them are C6-C 20 alkyl,

[0034] c) a pyridinium compound of formula C or a bipyridinium compound of formula D:

[0035] R 9 -(C5H5N + )-R 8 X - (C)

[0036] R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (D)

[0037] Where R 8 is an alkyl group and R 9 is a substituted or unsubstituted straight chain or branched chain alkyl or alkylene group, and

[0038] d) A free radical scavenger selected from the group consisting of hydroxybenzene, pyrazolone, a compound having a nitroxide free radical, gluconolactone, a tertiary alkyl alcohol and ascorbic acid.

[0039] The removal composition removes less molybdenum material from the surface of the microelectronic device than the aqueous alkaline composition.

[0040] The present disclosure also relates to a method for inhibiting etching of platinum material from the surface of a microelectronic device. The method comprises: i) providing an aqueous alkaline composition having a pH greater than 10, comprising water and at least one of the following: an organic additive, a cleaning additive, an organic solvent miscible with water, and a pH adjuster, ii) combining the aqueous alkaline composition and at least one platinum etching inhibitor to form a removal composition, the platinum etching inhibitor being selected from the group consisting of:

[0041] a) quaternary ammonium compounds of formula A:

[0042] Ar-RN + (R 1 )(R 2 )(R 3 )X - (A)

[0043] wherein Ar is a substituted or unsubstituted aryl group and X - is a hydroxyl ion, a halide ion, a sulfate ion or a methanesulfonate ion, and wherein:

[0044] 1) R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R3 At least one of them is C4-C 20 alkyl,

[0045] 2) R is C3-C 20 Alkylene and R 1 , R 2 and R 3 is methyl or ethyl, or

[0046] 3) R is C1-C 20 Alkylene, R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of contains a diol group,

[0047] b) quaternary ammonium compounds of formula B:

[0048] (R 4 )(R 5 )(R 6 )(R 7 )N + X - (B)

[0049] Where R 4 , R 5 , R 6 and R 7 is a straight chain or branched chain alkyl group and R 4 , R 5 , R 6 and R 7 At least two of them are C6-C 20 alkyl,

[0050] c) a pyridinium compound of formula C or a bipyridinium compound of formula D:

[0051] R 9 -(C5H5N + )-R 8 X - (C)

[0052] R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (D)

[0053] Where R 8 is an alkyl group and R 9 is a substituted or unsubstituted straight chain or branched chain alkyl or alkylene group, and

[0054] d) a free radical scavenger selected from the group consisting of hydroxybenzene, pyrazolone, a compound having a nitroxide free radical, gluconolactone, a tertiary alkyl alcohol and ascorbic acid, and

[0055] iii) contacting a surface of a microelectronic device comprising a molybdenum material with a removal composition. The removal composition removes less molybdenum from the surface of the microelectronic device than the aqueous alkaline composition. DETAILED DESCRIPTION

[0056] The present disclosure generally relates to aqueous removal compositions for removing post-CMP residues from surfaces of microelectronic devices. The removal compositions have a high pH and include various specific molybdenum etch inhibitors that surprisingly were found to reduce the amount of molybdenum etched from the device surface, even at a pH of 10 or higher, compared to the same composition without the molybdenum etch composition.

[0057] As used herein, the term "post-CMP residue" corresponds to contaminants generated by the use of CMP slurry, including, for example, particles of abrasives and chemicals present in the slurry, reaction byproducts of the polishing slurry, polishing pad particles, brush-off particles, equipment materials of the particles, metals, organic residues, and any other substances that are byproducts of the CMP process. In addition, if various metal layers are removed during the CMP process, the post-CMP residue may further include metal-containing particles.

[0058] For compositions disclosed in the present disclosure, where a particular component of the composition is discussed with reference to a weight percent range (including a zero lower limit), it is understood that the component may or may not be present in various specific embodiments of the composition, and where the component is present, it may be present in a concentration as low as 0.001 weight percent based on the total weight of the composition in which the component is used.

[0059] As used herein, the term "substantially free of" is defined as less than 2 wt.%, preferably less than 1 wt.%, more preferably less than 0.5 wt.%, and most preferably less than 0.1 wt.%. In view of environmental pollution, "free of" is intended to correspond to less than 0.001 wt.%. Therefore, "free of" can mean "free" of a particular component. In addition, as used herein, "about" is intended to correspond to ±5% of the stated value, such as ±2% or ±1% of the stated value.

[0060] As used herein, the term "microelectronic device" is not intended to be limited in any way and includes any substrate that will eventually become a microelectronic device or a microelectronic assembly. For example, "microelectronic device" corresponds to semiconductor substrates, flat panel displays, phase change memory devices, solar panels, and other products, including solar cell devices, photovoltaics, and microelectromechanical systems (MEMS), which are manufactured for microelectronics, integrated circuits, energy harvesting, or computer chip applications. A particularly preferred example of a microelectronic device is a 3D-NAND device. The device substrate from which the post-CMP residue can be removed by the composition described in the present disclosure can be any device substrate known in the art, including, for example, substrates comprising PETEOS, SiO2, thermal oxide, silicon nitride, silicon, etc.

[0061] Device substrates can be polished with CMP slurries containing abrasive particles (e.g., silica and ceria), organic agents, solvents, and other known components. Cleaning the polished substrate to the desired degree becomes increasingly difficult due to the strong interactions between the abrasive particles and the device surface, especially via H-bonds and van der Waals forces at low or moderate pH, and due to particle agglomeration and reprecipitation at high pH. Residues that are not removed often result in device defects.

[0062] Therefore, the present disclosure relates to removal compositions and methods for removing post-CMP residues from the surface of a microelectronic device. The removal composition comprises an aqueous alkaline composition having a pH greater than 10, the aqueous alkaline composition comprising water and at least one of the following: an organic additive, a cleaning additive, an organic solvent miscible with water, and a pH adjuster. The removal composition further comprises at least one type of specified molybdenum etch inhibitor.

[0063] Thus, the removal compositions described herein are high pH aqueous removal compositions having a pH greater than 10. Preferably, the pH of the removal composition is from about 10 to about 14, such as from about 12 to about 14, including a pH of 13 to 14. While aqueous compositions having such a high pH are generally expected to remove many types of post-CMP residues, they are also expected to remove various conductive metal layers, such as molybdenum layers. It is known that inhibiting etching of molybdenum at high pH while also providing adequate post-CMP residue removal is extremely difficult to achieve.

[0064] However, after extensive experimental studies, the inventors of the present case have identified various categories of platinum etching inhibitors, and surprisingly found that the platinum etching inhibitors combined with other additional components produce a high pH aqueous removal composition with reduced platinum etching but high post-CMP removal rate. As mentioned above, the removal composition comprises an aqueous (i.e., comprising more than 50% water) alkaline composition with a pH greater than 10. The aqueous alkaline composition further comprises at least one of the following: an organic additive, at least one cleaning additive, at least one organic solvent miscible with water, and at least one pH adjuster. For example, the aqueous alkaline composition may include one, two, three, or all four of these added components. Preferably, the aqueous alkaline composition includes each of these components. In addition to the aqueous alkaline composition, the removal composition further includes at least one specified type of platinum etching inhibitor. It has been unexpectedly found that, compared with an aqueous alkaline composition, i.e., a composition that is otherwise identical except for not containing these inhibitors, the high pH removal composition reduces platinum etching by including these specific categories of etching inhibitors.

[0065] Thus, the removal composition of the present disclosure comprises an aqueous alkaline composition having a pH greater than 10. Preferably, the pH of the aqueous alkaline composition is from about 10 to about 14, such as from about 12 to about 14, including a pH of 13 to 14. The pH of the composition can be adjusted by adding a desired amount of a pH adjuster to achieve a desired pH. The alkaline composition is an aqueous composition comprising greater than 50 wt % water, including greater than 60 wt % or greater than 70 wt % water.

[0066] In one embodiment, the aqueous removal composition comprises at least one pH adjusting agent. Examples of suitable pH adjusting agents include, but are not limited to, bases such as alkali metal hydroxides, alkaline earth metal hydroxides, tetraalkylammonium hydroxides (e.g., tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), and tetrabutylammonium hydroxide (TBAH)), tributylmethylammonium hydroxide (TBMAH), benzyltrimethylammonium hydroxide (BTMAH), choline hydroxide, ethyltrimethylammonium hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide, diethyldimethylammonium hydroxide, tetraalkylphosphonium hydroxides (e.g., tetrabutylphosphonium hydroxide (TBPH), tetramethylphosphonium hydroxide, tetraethylphosphonium hydroxide, and tetrapropylphosphonium hydroxide), benzyltriphenylphosphonium hydroxide, methyltriphenylphosphonium hydroxide, ethyltriphenylphosphonium hydroxide, N-propyltriphenylphosphonium hydroxide, and combinations thereof. Preferably, the pH adjusting agent comprises choline hydroxide.

[0067] The aqueous alkaline compositions described herein may be free of, and preferably substantially free of, ammonia or ammonium hydroxide. More preferably, ammonia and ammonium hydroxide are not present in the aqueous alkaline compositions. While these bases can be effective in raising the pH to a desired level, they present significant health and environmental issues and can significantly increase the cost of handling and mitigating these issues.

[0068] The pH adjuster may be present in any amount effective to provide and / or maintain a pH greater than 10. Specifically, the aqueous alkaline composition may include from about 0.1 wt % to about 40 wt % of the pH adjuster. Preferably, the amount of the pH adjuster is from about 1.0 wt % to about 30 wt %, and more preferably from about 3 wt % to about 20 wt %, including from about 5 wt % to about 10 wt %.

[0069] The aqueous alkaline composition may further comprise at least one organic additive. As used herein, an organic additive may be any compound capable of forming a composite structure with individual atoms / molecules / materials. Suitable organic additives include, but are not limited to, complexes such as aminoethylethanolamine, N-methylaminoethanol, aminoethoxyethanol, dimethylaminoethoxyethanol, diethanolamine, N-methyldiethanolamine, monoethanolamine (MEA), triethanolamine (TEA), 1-amino-2-propanol, 2-amino-1-butanol, isobutanolamine, triethylenediamine, 4-(2-hydroxyethyl)morpholine (HEM), ethylenediaminetetraacetic acid (EDTA), meta-xylene diamine (MXDA), iminodiacetic acid (IDA), 2-(hydroxyethyl)iminodiacetic acid (HIDA), nitrilotriacetic acid, thiourea, 1,1,3,3-tetramethylurea, urea, urea derivatives, uric acid, alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine, 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP), 1,5,9-triazacyclodecanoic acid dioxane-N,N',N"-tri(methylenephosphonic acid) (DOTRP), 1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetra(methylenephosphonic acid) (DOTP), nitrogen tri(methylene) triphosphonic acid, diethylenetriamine penta(methylenephosphonic acid) (DETAP), amino tri(methylenephosphonic acid), bis(hexamethylene) triamine pentamethylenephosphonic acid, 1,4,7-triazacyclononane-N,N',N"-tri(methylenephosphonic acid) (NOTP), hydroxyethyl diphosphate, The organic additive is selected from the group consisting of 1-amino-2-propanol and monoethanolamine.

[0070] The organic additive may be present in any amount effective to improve the removal rate of post-CMP residues. For example, when used, the aqueous alkaline composition may include about 0.1 wt % to about 20 wt % of the organic additive. Preferably, the amount of the organic additive is about 0.2 wt % to about 15 wt %, and more preferably about 0.3 wt % to about 10 wt %, including about 0.5 wt % to about 5 wt %.

[0071] The aqueous alkaline composition may further comprise at least one cleaning additive that aids in removing post-CMP residues from the surface of the microelectronic device. Examples of suitable cleaning additives include, for example, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, triethylene glycol monobutyl ether, ethylene glycol monophenyl ether, diethylene glycol monophenyl ether, propylene glycol monophenyl ether, dimethyl sulfoxide, cyclopentane, poly(styrene sulfonic acid) or its salts, poly(vinyl pyrrolidone), poly(vinyl pyrrolidone) / vinyl acetate, poly(vinyl acetate), poly(vinyl alcohol), homopolymers (e.g., phosphonated polyethylene glycol oligomers), poly(acrylamide), poly(acrylic acid) (PAA) and salts thereof (e.g., poly(acrylic acid) ammonium salt), poly(methacrylic acid) and salts thereof (e.g., poly(methacrylic acid) ammonium salt), acrylic acid and methacrylic acid homopolymers and copolymers with, for example, acrylamidomethylpropanesulfonic acid and maleic acid and salts thereof; poly(2-acrylamido-2-methyl-1-propanesulfonic acid) and copolymers thereof Polymer, polydiallyldimethylammonium chloride, poly(dimethylaminoethyl methacrylate) and its copolymers, poly(trimethylaminoethyl methacrylate) salt and its copolymers, poly(hydroxyethyl) acrylate (and its copolymers), poly(hydroxyethyl) methacrylate (and its copolymers), maleic acid / vinyl ether copolymer, poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG), polyethylene glycol-co-polypropylene glycol, PPG-PEG-PPG block copolymer, PEG-PPG-PEG block copolymer, poly(styrene sulfonic acid), poly(vinyl sulfonic acid), poly(vinyl phosphonic acid), poly(vinyl phosphoric acid), poly(ethylene imine), poly(propylene imine), polyallylamine, polyethylene oxide (PEO), hydroxyethyl cellulose, methyl hydroxyethyl cellulose, hydroxypropyl cellulose, methyl hydroxypropyl cellulose, xanthan gum (xanthan gum gum), potassium alginate, pectin, carboxymethylcellulose, glucosamine, poly(diallyldimethylammonium chloride), PEGylated (i.e., polyethylene glycolized) methacrylate / acrylate copolymers, poly(2-methacryloyloxyethyltrimethylammonium chloride) and copolymers thereof, ethoxylated alcohols or phenols, ethoxylated fatty acid sugars, dodecylbenzenesulfonic acid, laurylsulfonic acid, octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, benzyldimethyldodecylammonium chloride, benzyldimethyldodecylammonium hydroxide and trimethyldodecylammonium chloride and combinations thereof. The above copolymers may be random or block copolymers. Preferably, the cleaning additive is selected from the group consisting of nonanoic acid, ethoxylated alcohols, poly(acrylic acid), diethylene glycol monobutyl ether, ethylene glycol monohexyl ether and dodecylbenzenesulfonic acid (DDBSA).

[0072] When present, the amount of the cleaning additive in the aqueous alkaline composition is in the range of about 0.001 wt % to about 20 wt %, based on the total weight of the aqueous alkaline composition. For example, the cleaning additive can be present in an amount of about 0.1 wt % to about 10 wt %, including an amount of about 0.5 wt % to about 5 wt %, based on the total weight of the composition.

[0073] The aqueous alkaline composition may further comprise at least one organic solvent miscible with water. Examples of suitable water-miscible solvents include, for example, glycols, glycol ethers, methanol, ethanol, isopropanol, butanol, and higher alcohols selected from C2-C4 glycols and C2-C4 triols, tetrahydrofurfuryl alcohol (e.g., 3-chloro-1,2-propylene glycol, 3-chloro-1-propanethiol, 1-chloro-2-propanol, 2-chloro-1-propanol, 3-chloro-1-propanol, 3-bromo-1,2-propylene glycol, 1-bromo-2-propanol, 3-bromo-1-propanol, 3-iodo-1-propanol, , 4-chloro-1-butanol, 2-chloroethanol), dichloromethane, chloroform, acetic acid, propionic acid, trifluoroacetic acid, tetrahydrofuran, N-methylpyrrolidone, cyclohexylpyrrolidone, N-octylpyrrolidone, N-phenylpyrrolidone, methyldiethanolamine, methyl formate, dimethylformamide, dimethyl sulfoxide, tetramethylene sulfone, ethyl ether, phenoxy-2-propanol, propylisophenyl ketone, ethyl lactate, ethyl acetate, ethyl benzoate, acetonitrile, acetone, ethylene glycol, propylene glycol, 1 ,3-propylene glycol, dioxane, butyrolactone, butylene carbonate, ethylene carbonate, propylene carbonate, dipropylene glycol, diethylene glycol monomethyl ether, triethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, ethylene glycol phenyl ether, propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, dipropylene glycol dimethyl ether, dipropylene Glycol ethyl ether, propylene glycol n-propyl ether, dipropylene glycol n-propyl ether, tripropylene glycol n-propyl ether, propylene glycol n-butyl ether, dipropylene glycol n-butyl ether, tripropylene glycol n-butyl ether, propylene glycol phenyl ether, ethylene glycol monophenyl ether, diethylene glycol monophenyl ether, hexaethylene glycol monophenyl ether, dipropylene glycol methyl ether acetate, tetraethylene glycol dimethyl ether, dibasic esters, glycerol carbonate, N-formylmorpholine, triethyl phosphate, glycerol, sorbitol, glycol ethers, urea, dicyandiamide and combinations thereof. Preferably, the water-miscible solvent is selected from the group consisting of glycerol and sorbitol.

[0074] When present, the amount of water-miscible solvent in the aqueous alkaline composition is in the range of about 0.1 wt % to about 20 wt %, based on the total weight of the aqueous alkaline composition. For example, the cleaning additive can be present in an amount of about 0.2 wt % to about 15 wt %, including about 0.5 wt % to about 10 wt %, about 1.0 wt % to about 10 wt %, or about 5.0 wt % to about 10 wt %, based on the total weight of the composition.

[0075] Thus, the aqueous alkaline composition comprises water and at least one of the following: an organic additive, a cleaning additive, an organic solvent miscible with water, and a pH adjuster, and has a pH greater than 10. This composition can be used as a base to form a removal composition by including at least one platinum etching inhibitor, which is used to remove post-CMP residues from the surface of a microelectronic device. The etching inhibitor and the aqueous alkaline composition can be combined in any manner known in the art to form a removal composition. For example, the inhibitor can be combined with a preformed aqueous alkaline composition or can be included when forming the aqueous alkaline composition.

[0076] More specifically, the removal composition comprises an aqueous alkaline composition and at least one molybdenum etch inhibitor. The inhibitor is selected from the group consisting of: having the formula Ar-RN + (R 1 )(R 2 )(R 3 )X - (referred to herein as Formula A) quaternary ammonium compounds having the formula (R 4 )(R 5 )(R 6 )(R 7 )N + X - (referred to herein as Formula B) quaternary ammonium compounds having the formula R 9 -(C5H5N + )-R 8 X - (referred to herein as Formula C) , a pyridinium compound having Formula R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (referred to herein as Formula D) and a radical scavenger selected from the group consisting of hydroxybenzenes, pyrazolones, compounds having nitroxide radicals, gluconolactones, tertiary alkyl alcohols, and ascorbic acid. By including at least one of these selected types of etching inhibitors, it was unexpectedly discovered that the removal composition removes less platinum from the surface of a microelectronic device containing platinum than an aqueous alkaline composition without significantly affecting its ability to remove post-CMP residues from the device surface.

[0077] Thus, the removal composition comprises a quaternary ammonium compound of formula A:

[0078] Ar-RN + (R 1 )(R 2 )(R 3 )X -(A).

[0079] In this formula, Ar is a substituted or unsubstituted aryl group, such as a phenyl group, and X - is a counter ion, such as a hydroxyl ion, a halide ion, a sulfate ion or a methanesulfonate ion. As a specific embodiment of the quaternary ammonium compound of formula A, R is a methylene or ethylene group; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of them is C4-C 20 For example, R 1 , R 2 and R 3 Can be C 10 -C 20 As another specific embodiment of the quaternary ammonium compound of formula A, R is C3-C 20 Alkylene and R 1 , R 2 and R 3 is methyl or ethyl. For example, R can be C4-C 10 As another specific embodiment, R is C1-C 20 Alkylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of the quaternary ammonium compounds of formula A comprises a diol group. For example, the diol group can be an ethylene glycol group. Specific examples of suitable quaternary ammonium compounds of formula A include benzyl dodecyl dimethyl ammonium salt, benzyl tetradecyl dimethyl ammonium salt, phenylpropyl triethyl ammonium salt or phenylethyl ammonium salt.

[0080] Alternatively or additionally, the removal composition comprises a quaternary ammonium compound of formula B:

[0081] (R 4 )(R 5 )(R 6 )(R 7 )N + X - (B).

[0082] In this formula, R 4 , R 5 , R 6 and R 7 is a straight chain or branched chain alkyl group and R 4 , R 5 , R 6 and R7 At least two of them are C6-C 20 In a particular embodiment, R 4 , R 5 , R 6 and R 7 At least three of them are C6-C 20 Specific examples of suitable quaternary ammonium compounds of formula B include tetrapropylammonium salts, tetrabutylammonium salts or methyltrioctylammonium salts.

[0083] Alternatively or additionally, the removal composition comprises a pyridinium compound of Formula C:

[0084] R 9 -(C5H5N + )-R 8 X - (C)

[0085] Or a bipyridinium compound of formula D:

[0086] R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (D)

[0087] In these formulas, R 8 is an alkyl group and R 9 is a substituted or unsubstituted straight or branched chain alkyl or alkylene. Specific examples of suitable pyridinium compounds of formula C include N-ethyl-4-(3-phenylpropyl)pyridine, and specific examples of suitable bipyridinium compounds of formula D include ethyl viologen dihalide salts.

[0088] Alternatively or additionally, the removal composition comprises a radical scavenger selected from the group consisting of hydroxybenzene, pyrazolone, compounds with nitroxide radicals, gluconolactone, tertiary alkyl alcohols and ascorbic acid. Specific examples of suitable radical scavengers include 2,5-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 4-hydroxy-TEMPO, 4-phosphino-TEMPO, 3-methyl-1-phenyl-2-pyrazolin-5-one, trans-4-hydroxycinnamic acid, guaiacol, tert-butyl alcohol or glucono-1,5-lactone.

[0089] When present, the amount of the platinum etch inhibitor in the removal composition is in the range of about 0.05 wt % to about 10 wt % based on the total weight of the removal composition. For example, the platinum etch inhibitor additive can be present in an amount of about 0.1 wt % to about 8.0 wt %, including about 0.2 wt % to about 5.0 wt %, based on the total weight of the composition.

[0090] Examples

[0091] The aqueous removal compositions of the present disclosure were prepared by combining various aqueous alkaline compositions and specific platinum etching inhibitors as shown in Table 1 below. Comparative exemplary removal compositions were similarly prepared and are also included in this table. Specific information about the aqueous alkaline compositions is shown in Tables 2A to 2C, and the inhibitors used are shown in Table 3. The platinum etching rate was determined by exposing a test piece having a platinum layer to the specified composition at a temperature of 30°C.

[0092] As shown in the results, it was found that the compositions containing inhibitors described in the present disclosure had a significant inhibitory effect on platinum etching, while there was no significant reduction in post-CMP residue removal. Compounds with similar structures but not meeting the specific requirements outlined herein (i.e., comparative compounds) did not achieve inhibition of platinum etching.

[0093] Table 1

[0094]

[0095]

[0096] Table 2A - Aqueous alkaline composition 1 (AB-1) - pH = 13.4

[0097] Components CAS# Wt% water 82.94 1-Amino-2-propanol 78-96-6 4.0 Ethylene glycol monohexyl ether 112-25-4 0.50 4-Dodecylbenzenesulfonic acid(DDBSA) 121-65-3 0.01 glycerin 56-81-5 6.0 Choline Hydroxide 123-41-1 6.55

[0098] Table 2B - Aqueous alkaline composition 2 - pH = 13.4

[0099] Components CAS# Wt% water 73.32 Monoethanolamine (MEA) 141-43-5 4.5 Nonanoic acid 112-05-0 4.38 Diethylene glycol monobutyl ether (BDG) 112-34-5 6.0 D-Sorbitol 50-70-4 6.0 Choline Hydroxide 123-41-1 5.8

[0100] Table 2C - Aqueous alkaline composition 3 - pH = 13.49

[0101] Components CAS# Wt% water 81.40 Monoethanolamine (MEA) 141-43-5 0.95 Poly(acrylic acid) 9003-07-4 0.50 Brij L23 9002-92-0 0.20 D-Sorbitol 50-70-4 9.0 Choline Hydroxide 123-41-1 7.96

[0102] Table 3

[0103]

[0104]

[0105]

[0106]

Claims

1. A removal composition for removing post-CMP residues from a surface of a microelectronic device, the removal composition comprising an aqueous alkaline composition having a pH greater than 10, the aqueous alkaline composition comprising water and at least one of: an organic additive, a cleaning additive, a water-miscible organic solvent, and a pH adjuster, wherein the removal composition further comprises at least one molybdenum etch inhibitor selected from the group consisting of: a) quaternary ammonium compounds of formula A: Ar-R-N + (R 1 )(R 2 )(R 3 )X - (A), wherein Ar is a substituted or unsubstituted aryl group and X - is a hydroxyl ion, a halide ion, a sulfate ion or a methanesulfonate ion, and wherein: 1) R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of them is C4-C 20 alkyl, 2) R is C3-C 20 Alkylene and R 1 , R 2 and R 3 is methyl or ethyl, or 3) R is C1-C 20 Alkylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of contains a diol group, b) quaternary ammonium compounds of formula B: (R 4 )(R 5 )(R 6 )(R 7 )N + X - (B), Where R 4 , R 5 , R 6 and R 7 is a straight chain or branched chain alkyl group and R 4 , R 5 , R 6 and R 7 At least two of them are C6-C 20 alkyl, c) a pyridinium compound of formula C or a bipyridinium compound of formula D: R 9 -(C5H5N + )-R 8 X - (C), R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (D) Where R 8 is an alkyl group and R 9 is a substituted or unsubstituted straight chain or branched chain alkyl or alkylene group, and d) a free radical scavenger selected from the group consisting of hydroxybenzenes, pyrazolones, compounds having nitroxide radicals, gluconolactone, tertiary alkyl alcohols and ascorbic acid, And wherein the removal composition removes less molybdenum from a surface of a microelectronic device comprising molybdenum than the aqueous alkaline composition.

2. The removal composition of claim 1, wherein the platinum etching inhibitor is a quaternary ammonium compound of formula A, wherein R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of them is C4-C 20 alkyl.

3. The removal composition according to claim 2, wherein R 1 , R 2 and R 3 At least one of them is C 10 -C 20 alkyl.

4. The removal composition of claim 1, wherein the platinum etching inhibitor is a quaternary ammonium compound of formula A, wherein R is C3-C 20 Alkylene and R 1 , R 2 and R 3 It is methyl or ethyl.

5. The removal composition according to claim 4, wherein R is C4-C 10 Alkylene.

6. The removal composition of claim 1, wherein the platinum etching inhibitor is a quaternary ammonium compound of formula A, wherein R is C1-C 20 Alkylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of the compounds comprises a diol group.

7. The removal composition of claim 6, wherein the diol group is an ethylene glycol group.

8. The removal composition according to claim 1, wherein the quaternary ammonium compound of formula A is benzyldodecyldimethylammonium salt, benzyltetradecyldimethylammonium salt, phenylpropyltriethylammonium salt or phenylethylammonium salt.

9. The removal composition of claim 1, wherein the molybdenum etch inhibitor is a quaternary ammonium compound of formula B.

10. The removal composition according to claim 9, wherein R 4 , R 5 , R 6 and R 7 At least three of them are C6-C 20 alkyl.

11. The removal composition according to claim 9, wherein the molybdenum etching inhibitor is a tetrapropylammonium salt, a tetrabutylammonium salt or a methyltrioctylammonium salt.

12. The removal composition of claim 1, wherein the molybdenum etch inhibitor is a pyridinium compound of Formula C.

13. The removal composition of claim 12, wherein the molybdenum etch inhibitor is N-ethyl-4-(3-phenylpropyl)pyridine.

14. The removal composition of claim 1, wherein the molybdenum etch inhibitor is a bipyridylium compound of Formula D.

15. The removal composition of claim 14, wherein the molybdenum etch inhibitor is an ethyl viologen dihalide salt.

16. The removal composition of claim 1, wherein the platinum etch inhibitor is a free radical scavenger selected from the group consisting of 2,5-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 4-hydroxy-TEMPO, 3-methyl-1-phenyl-2-pyrazol-5-one, trans-4-hydroxycinnamic acid, guaiacol, tert-butyl alcohol, or glucono-1,5-lactone.

17. The removal composition of claim 1, wherein the pH of the removal composition is from about 10 to about 14.

18. The removal composition of claim 1, wherein the pH of the removal composition is from about 11 to about 13.

5.

19. A method of removing post-CMP residue from a surface of a microelectronic device comprising a molybdenum material, the method comprising: i) contacting the surface of the microelectronic device with a removal composition comprising an aqueous alkaline composition having a pH greater than 10, the aqueous alkaline composition comprising water and at least one of: an organic additive, a cleaning additive, a water-miscible organic solvent, and a pH adjuster, wherein the removal composition further comprises at least one molybdenum etch inhibitor selected from the group consisting of: a) quaternary ammonium compounds of formula A: Ar-R-N + (R 1 )(R 2 )(R 3 )X - (A), wherein Ar is a substituted or unsubstituted aryl group and X - is a hydroxyl ion, a halide ion, a sulfate ion or a methanesulfonate ion, and wherein: 1) R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of them is C4-C 20 alkyl, 2) R is C3-C 20 Alkylene and R 1 , R 2 and R 3 is methyl or ethyl, or 3) R is C1-C 20 Alkylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of contains a diol group, b) quaternary ammonium compounds of formula B: (R 4 )(R 5 )(R 6 )(R 7 )N + X - (B), Where R 4 , R 5 , R 6 and R 7 is a straight chain or branched chain alkyl group and R 4 , R 5 , R 6 and R 7 At least two of them are C6-C 20 alkyl, c) a pyridinium compound of formula C or a bipyridinium compound of formula D: R 9 -(C5H5N + )-R 8 X - (C), R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (D) Where R 8 is an alkyl group and R 9 is a substituted or unsubstituted straight chain or branched chain alkyl or alkylene group, and d) a free radical scavenger selected from the group consisting of hydroxybenzene, pyrazolone, a compound having a nitroxide free radical, gluconolactone, a tertiary alkyl alcohol and ascorbic acid; and ii) at least partially removing the post-CMP residue from the surface of the microelectronic device, Wherein the removal composition removes less of the molybdenum material from the surface of the microelectronic device than the aqueous alkaline composition.

20. The method of claim 19, wherein the platinum etch inhibitor is a quaternary ammonium compound of formula A, wherein R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group, and R 1 , R 2 and R 3 At least one of them is C4-C 20 alkyl.

21. The method according to claim 20, wherein R 1 , R 2 and R 3 At least one of them is C 10 -C 20 alkyl.

22. The method of claim 19, wherein the platinum etch inhibitor is a quaternary ammonium compound of formula A, wherein R is C3-C 20 Alkylene and R 1 , R 2 and R 3 It is methyl or ethyl.

23. The method of claim 22, wherein R is C4-C 10 Alkylene.

24. The method of claim 19, wherein the platinum etch inhibitor is a quaternary ammonium compound of formula A, wherein R is C1-C 20 Alkylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of the compounds comprises a diol group.

25. The method of claim 24, wherein the diol group is an ethylene glycol group.

26. The method according to claim 19, wherein the quaternary ammonium compound of formula A is benzyldodecyldimethylammonium salt, benzyltetradecyldimethylammonium salt, phenylpropyltriethylammonium salt or phenylethylammonium salt.

27. The method of claim 19, wherein the molybdenum etch inhibitor is a quaternary ammonium compound of Formula B.

28. The method according to claim 27, wherein R 4 , R 5 , R 6 and R 7 At least three of them are C6-C 20 alkyl.

29. The method of claim 27, wherein the molybdenum etching inhibitor is a tetrapropylammonium salt, a tetrabutylammonium salt, or a methyltrioctylammonium salt.

30. The method of claim 19, wherein the molybdenum etch inhibitor is a pyridinium compound of Formula C.

31. The method of claim 30, wherein the molybdenum etch inhibitor is N-ethyl-4-(3-phenylpropyl)pyridine.

32. The method of claim 19, wherein the molybdenum etch inhibitor is a bipyridylium compound of formula D.

33. The method of claim 32, wherein the platinum etch inhibitor is an ethyl viologen dihalide salt.

34. The method of claim 19, wherein the platinum etch inhibitor is a free radical scavenger selected from the group consisting of 2,5-dihydroxybenzoic acid, 2,3-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 4-hydroxy-TEMPO, 3-methyl-1-phenyl-2-pyrazolin-5-one, trans-4-hydroxycinnamic acid, guaiacol, tert-butyl alcohol, or glucono-1,5-lactone.

35. The method of claim 19, wherein the pH of the removal composition is about 10 to about 14.

36. The method of claim 19, wherein the pH of the removal composition is about 11 to about 13.

5.

37. A method of inhibiting etching of molybdenum material from a surface of a microelectronic device, the method comprising: i) providing an aqueous alkaline composition having a pH greater than 10, comprising water and at least one of: an organic additive, a cleaning additive, a water-miscible organic solvent, and a pH adjuster, ii) combining the aqueous alkaline composition and at least one platinum etch inhibitor selected from the group consisting of: a) quaternary ammonium compounds of formula A: Ar-R-N + (R 1 )(R 2 )(R 3 )X - (A), wherein Ar is a substituted or unsubstituted aryl group and X - is a hydroxyl ion, a halide ion, a sulfate ion or a methanesulfonate ion, and wherein: 1) R is methylene or ethylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of them is C4-C 20 alkyl, 2) R is C3-C 20 Alkylene and R 1 , R 2 and R 3 is methyl or ethyl, or 3) R is C1-C 20 Alkylene; R 1 , R 2 and R 3 is a straight chain or branched chain alkyl group; and R 1 , R 2 and R 3 At least one of contains a diol group, b) quaternary ammonium compounds of formula B: (R 4 )(R 5 )(R 6 )(R 7 )N + X - (B), Where R 4 , R 5 , R 6 and R 7 is a straight chain or branched chain alkyl group and R 4 , R 5 , R 6 and R 7 At least two of them are C6-C 20 alkyl, c) a pyridinium compound of formula C or a bipyridinium compound of formula D: R 9 -(C5H5N + )-R 8 X - (C), R 8 -( + NC5H5)-(C5H5N + )-R 8 X - (D) Where R 8 is an alkyl group and R 9 is a substituted or unsubstituted straight chain or branched chain alkyl or alkylene group, and d) a free radical scavenger selected from the group consisting of hydroxybenzene, pyrazolone, a compound having a nitroxide free radical, gluconolactone, a tertiary alkyl alcohol and ascorbic acid, and iii) contacting the surface of the microelectronic device comprising a molybdenum material with the removal composition, wherein the removal composition removes less molybdenum from the surface of the microelectronic device than the aqueous alkaline composition.

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