TW201339299A - A post chemical-mechanical-polishing (post-CMP) cleaning composition comprising a specific sulfur-containing compound and comprising no significant amounts of specific nitrogen-containing compounds - Google Patents

Abstract

A post chemical-mechanical-polishing (post-CMP) cleaning composition comprising: (A) at least one compound comprising at least one thiol (-SH), thioether (-SR1) or thiocarbonyl (> C=S) group, wherein R1 is alkyl, aryl, alkylaryl or arylalkyl, and (B) an aqueous medium, wherein the total amounts of NH4+, any sulfur-free organic ammonium ions, and any sulfur-free amines comprised in the composition do not exceed 100 ppm based on the total weight of the composition.

Description

a chemical mechanical polishing cleaning composition comprising a specific sulfur-containing compound and a specific nitrogen-containing compound containing a non-effective amount

The present invention is basically directed to a chemical mechanical polishing (post-CMP) cleaning composition and its use for removing residues and contaminants from the surface of a semiconductor substrate. Furthermore, the present invention relates to the use of the post-CMP cleaning composition to remove residues and contaminants comprising benzotriazole after CMP. In particular, the present invention relates to the post-CMP cleaning composition comprising a conductive layer (eg, a copper layer), an electrically insulating dielectric layer (eg, a layer of low-k or ultra-low-k dielectric material), and a barrier layer after CMP ( The use of a surface of a semiconductor substrate such as tantalum, tantalum nitride, titanium nitride or tantalum to remove residues and contaminants.

In the semiconductor industry, chemical mechanical polishing (abbreviated as CMP) is a well-known technique for fabricating advanced photonic, microelectromechanical, and microelectronic materials and devices, such as semiconductor wafers.

During the fabrication of materials and devices for the semiconductor industry, CMP is employed to planarize the surface of the metal and/or oxide. CMP utilizes the interaction of chemical and mechanical interactions to achieve planarization of the surface to be polished. The CMP method itself comprises subjecting a flat thin substrate of the semiconductor device to a wet polishing pad under controlled pressure and temperature and in the presence of a CMP slurry. Let it rotate. The CMP slurries comprise abrasive materials and various chemical additives suitable for the particular CMP process and requirements. After the CMP treatment, contaminants and residues containing particles from the CMP slurry, added chemicals, and reaction by-products remain on the surface of the polished substrate. The residue remaining on the substrates after CMP treatment may also include a corrosion inhibitor compound (such as benzotriazole (BTA)), which may (if, for example, copper ion concentration exceeds copper during CMP) The maximum solubility of the agent complex) precipitates from the solution and condenses into surface residues. Additionally, polishing a substrate surface having a copper/low k or ultra low k dielectric material typically produces carbon-rich particles that are fixed to the surface after CMP.

However, all residues and contaminants must be removed prior to any other steps in the microelectronic device fabrication process to avoid degrading the device reliability and introducing defects into the microelectronic devices.

A post-CMP cleaning composition containing a compound comprising a thiol group, a thioether group or a thiocarbonyl group is known in the state of the art and is described, for example, in the following references.

US 2005/0197266 A1 discloses a composition for cleaning a semiconductor workpiece, the composition comprising: (a) a cleaning agent selected from the group consisting of: (i) ammonium citrate, (ii) ammonium oxalate, (iii) Aspartic acid, (iv) benzoic acid, (v) citric acid, (vi) cysteine, (vii) glycine, (viii) gluconic acid, (ix) glutamic acid, (x) group An amine, (xi) maleic acid, (xii) oxalic acid, (xiii) propionic acid, (xiv) salicylic acid, (xv) tartaric acid, and (xvi) a mixture thereof; and (b) selected from the group consisting of Corrosion inhibitors: (i) ascorbic acid, (ii) benzotriazole, (iii) caffeic acid, (iv) cinnamic acid, (v) cysteine, (vi) glucose, (vii) imidazole, (viii Mercaptothiazoline, (ix) mercaptoethanol, (x) mercaptopropionic acid, (xi) mercaptobenzothiazole, (xii) mercaptomethylimidazole, (xiii) tannic acid, (xiv) sulfur glycerol, (xv) sulfur Salicylic acid, (xvi) triazole, (xvii) vanillin, (xviii) vanillic acid, and (xix) mixtures thereof. For example, the cleaning composition comprises ammonium citrate, ascorbic acid, and cysteine.

WO 2011/000694 A1 discloses an aqueous alkaline cleaning composition comprising (a) At least one primary amine group and at least one thiol group, at least one thioamino acid, (b) at least one quaternary ammonium hydroxide, (c) at least one specific chelating agent and/or corrosion inhibitor, and (d) at least one of An organic solvent having a wetting property and a melting point below 0 °C. For example, the cleaning composition comprises L-cysteine, tetramethylammonium hydroxide (hereinafter referred to as TMAH), ethylenediamine, and diethylene glycol monobutyl ether.

WO 2011/000758 A1 discloses an aqueous alkaline cleaning composition comprising (a) at least one thioamino acid having at least one secondary or tertiary amine group and at least one thiol group, (b) at least one oxyhydroxide quaternary acid Ammonium. For example, the cleaning composition comprises N-acetylcysteine, TMAH, ethylenediamine, and diethylene glycol monobutyl ether. In another example, the cleaning composition comprises N-acetylcysteine, TMAH, di-ethyltriamine, 1,2,4-triazole, citric acid, and a surfactant (eg, 3,5- Dimethyl-1-hexyn-3-ol or polyoxyethylene sorbitan laurate).

In the above state of the art, a post-CMP cleaning composition comprising: (a) a compound comprising a thiol group, a thioether group or a thiocarbonyl group, and (b) an effective amount of NH ₄ ⁺ or a sulfur-free organic ammonium salt is disclosed. Salt or sulfur-free amine.

The object of the invention

One object of the present invention is to provide a post-CMP cleaning composition and a post-CMP cleaning method suitable for cleaning a copper-containing microelectronic substrate after CMP and exhibiting improved cleaning performance. Specifically, the improved cleaning performance is: i) effectively preventing undesired corrosion of the copper-containing surface; or (ii) efficiently removing residues and contaminants remaining after the CMP step; or (iii) efficiently removing the passivation film from the copper-containing surface (especially benzo Triazole film); or (iv) safe handling and minimizing harmful components; or (v) applicability in the medium pH range (eg 4 to 8); or (vi) (i) to (v) combination.

Additionally, it is an object of the present invention to provide a post-CMP cleaning composition that does not contain or contain a minimum amount of organic solvent that can cause environmental and safety concerns. Furthermore, it is an object of the present invention to provide a post-CMP cleaning composition which does not increase the surface roughness of the copper-containing surface or increase the defects thereon. Finally, it is equally important to find a post-CMP cleaning method that is easy to use safely and requires as few steps as possible.

Accordingly, a post-CMP cleaning composition comprising: (A) at least one compound comprising at least one thiol group (-SH), a thioether group (-SR ¹ ) or a thiocarbonyl group (>C=S), is found. Wherein R ¹ is an alkyl group, an aryl group, an alkylaryl group or an aralkyl group; and (B) an aqueous medium, wherein the composition comprises NH ₄ ⁺ , any sulfur-free organic ammonium ion, and any sulfur-free medium. The total amount of amines does not exceed 100 ppm ("ppm" stands for "parts per million") (based on the total weight of the composition). This post-CMP cleaning composition of the present invention is hereinafter referred to as (Q) or composition (Q).

Furthermore, the use of such a composition (Q) to remove residues and contaminants from the surface of a semiconductor substrate used to fabricate microelectronic devices has been discovered.

Additionally, a method of fabricating a microelectronic device from a semiconductor substrate is disclosed that includes the steps of removing residues and contaminants from the surface of the semiconductor substrate by contacting the semiconductor substrate with the composition (Q) at least once. . This method of the invention is hereinafter referred to as method (P).

The preferred embodiments are set forth in the claims and in the specification. Combinations of the preferred embodiments are understood to be within the scope of the invention.

Advantages of the invention

With respect to the above prior art, the composition (Q) and the method (P) can solve the basic object of the present invention surprisingly and unanticipated by those skilled in the art.

Particularly surprisingly, the composition (Q) and the method (P) are extremely suitable for post-processing for the manufacture of electronic devices (specifically, semiconductor integrated circuits (IC), more preferably with LSI (large scale) Substrate for integration) or VLSI (very large scale integration) IC). Even more surprisingly, the composition (Q) and the method (P) are most suitable for high precision manufacturing processes including, inter alia, surface treatment, pre-plating cleaning, post-etch cleaning and/or post-CMP cleaning steps. The composition (Q) and the method (P) are most particularly suitable for performing the above-described cleaning step (specifically, post-CMP cleaning of a semiconductor wafer) and manufacturing an IC having LSI or VLSI (specifically, by copper Mosaic or dual mosaic method).

The composition (Q) and the method (P) most effectively remove all kinds of residues and contamination generated during surface treatment, deposition, plating, etching, and CMP (specifically during CMP) of the substrate. And to ensure that such substrates (specifically, ICs) do not contain residues and contaminants that would otherwise adversely affect the function of the electronic and optical device (specifically, the IC) or that would otherwise be ineffective. In particular, the composition (Q) and the method (P) prevent scratching, etching and roughening of the copper metallization layer in the damascene structure. Additionally, the composition (Q) and the method (P) may also completely remove the passivation film (especially a benzotriazole film) from the copper-containing surfaces. Furthermore, the composition (Q) and the method (P) prevent corrosion of the copper-containing surfaces. Finally, it is also important that the composition (Q) and the method (P) are suitable for use in the medium pH range (for example 4 to 8).

Furthermore, surprisingly, despite containing a thiol group or a thiamine compound of the prior art cleaning compositions also comprise an ammonium salt (e.g., TMAH or NH ₄ ^+), but lacking NH ₄ ^+, without any organic ammonium ion of sulfur And any sulfur-free amine does not affect the cleaning performance of the cleaning composition. TMAH is quite detrimental and the NH ₄ ⁺ cation can be readily converted to corrosive and harmful NH ₃ , so the absence of such materials in the cleaning composition is beneficial to the handling and safety of the cleaning composition. In addition, NH ₄ ⁺ (which can be converted to NH ₃ ) and sulfur-free organic ammonium ions (which can be converted to the corresponding amine) and sulfur-free amine can cause contamination problems in subsequent manufacturing steps of the semiconductor device, This cleaning composition is not included in the cleaning composition to avoid.

Figure 1 shows the SEM analysis results of the No. 1 immersion test using the cleaning compositions S31, S32, S33, and S34 and the SEM analysis results of the control sample Z.

2 shows the SEM analysis results of the immersion test No. 2 using the cleaning compositions S35, S36, S37, S38, S39, and S40, and the SEM analysis results of the control sample Y.

Figure 3 shows the results of SEM analysis using No. 2 immersion test of cleaning compositions S41, S42, S43, S44, S45 and S46.

The composition (Q) is used to remove residues and contaminants from the surface of a semiconductor substrate used in the fabrication of microelectronic devices. The residues and contaminants may be any residue and contaminants including, but not limited to, abrasive particles, processing residues, metal oxides including copper oxide, metal ions, salts, passivation films, and low wear or decomposition. k or ultra low k dielectric material. Preferably, the residue and the contaminant comprise a passivation film, more preferably an N-heterocyclic compound, preferably comprising a diazole, a triazole, a tetrazole or a derivative thereof, particularly preferably a benzotriazole or a derivative thereof. For example, it contains benzotriazole. In particular, (Q) is used to remove residues and contaminants comprising benzotriazole or its derivatives from the copper-containing surface of the semiconductor substrate after CMP. For example, (Q) is used to remove a passivation film comprising benzotriazole from the copper-containing surface of the semiconductor substrate after CMP.

Preferably, the composition (Q) is used to remove residues and contaminants from the surface of the semiconductor substrate used to fabricate the microelectronic device after CMP. More preferably, the composition (Q) is used to remove residues and contaminants from the surface after it has been polished in the CMP step.

Preferably, the semiconductor substrate comprises a conductive layer, an electrically insulating dielectric layer and a barrier layer, more preferably: - a conductive layer comprising or consisting of copper; - an electrically insulating dielectric composed of a low-k or ultra-low-k dielectric material Electrical layer; and - containing tantalum, tantalum nitride, titanium nitride, cobalt, nickel, manganese, tantalum, tantalum nitride, tantalum carbide Or a tantalum nitride or a barrier layer composed thereof.

Although the composition (Q) can be advantageously used for other purposes, it is particularly suitable for the method (P).

A microelectronic device can be fabricated from a semiconductor substrate by the method (P), the method (P) comprising removing residuals from the surface of the semiconductor substrate by contacting the semiconductor substrate with the composition (Q) at least once Steps for substances and contaminants. Preferably, the residue and the contaminant comprise a passivation film, more preferably an N-heterocyclic compound, preferably comprising a diazole, a triazole, a tetrazole or a derivative thereof, particularly preferably a benzotriazole or a derivative thereof. For example, it contains benzotriazole. In particular, (P) includes removing the residue comprising benzotriazole or a derivative thereof and contaminants from the copper-containing surface of the semiconductor substrate by contacting the semiconductor substrate with (Q) at least once. step.

Preferably, the method (P) includes the step of removing the residue and contaminants from the surface of the semiconductor substrate by contacting the semiconductor substrate with the composition (Q) at least once after CMP. More preferably, the method (P) comprises contacting the semiconductor substrate with the composition (Q) at least once by polishing the surface of the semiconductor substrate after being polished in the CMP step to remove residues and contaminants from the surface. The steps.

The method (P) can be used not only for post-CMP cleaning but also for photoresist stripping and post-etch residue removal. However, this method (P) shows its specific advantages in the post-CMP cleaning of the above semiconductor substrate.

The composition (Q) comprises at least one compound (A) comprising at least one thiol group (-SH), a thioether group (-SR ¹ ) or a thiocarbonyl group (>C=S), wherein the R ¹ is an alkyl group , aryl, alkaryl or aralkyl. Preferably, the composition (Q) comprises a compound (A).

In general, the composition (Q) may comprise varying amounts of the compound (A), and the content or concentration of (A) may be most advantageously adjusted according to the specific requirements of the specified compositions, uses and methods of the invention. The content of (A) is preferably not more than 1.5% by weight (hereinafter referred to as "% by weight"), more preferably not more than 0.5% by weight, most preferably not more than 0.1% by weight, especially not more than 0.07. % by weight, for example not more than 0.05% by weight, based on the total weight of the composition (Q). The content of (A) is preferably at least 0.0005 wt%, more preferably at least 0.001 wt%, most preferably at least 0.004 wt%, especially at least 0.01 wt%, such as at least 0.03 wt% (based on the total weight of the composition (Q)) .

Preferably, the compound (A) comprises the following compounds: (A1) at least one thiol group (-SH), a thioether group (-SR ¹ ) or a thiocarbonyl group (>C=S); and (A2) At least one amine group (-NH ₂ , -NHR ² or -NR ³ R ⁴ ), wherein R ¹ , R ² , R ³ and R ⁴ are each independently alkyl, aryl, alkaryl or aralkyl. In the case of the (A2) moiety, it is generally preferred to use the amine group -NH ₂ and -NHR ₂ and the amine group -NH _{2 is} preferred.

According to an embodiment, the compound (A) preferably comprises the following compounds: (A1) at least one thiocarbonyl group (>C=S); and (A2) at least one amine group (-NH ₂ , -NHR ² or - NR ³ R ⁴ ), wherein R ² , R ³ and R ⁴ are each independently alkyl, aryl, alkaryl or aralkyl. More preferably, (A) comprises the following compounds: (A1) a thiocarbonyl group (>C=S); and (A2) at least two amine groups (-NH ₂ , -NHR ² or -NR ³ R ⁴ ) .

Most preferably, (A) is a thiourea or a derivative thereof. In particular, (A) is a thiourea.

According to another embodiment, the compound (A) preferably comprises the following compound: (A1) at least one thiol group (-SH) or thioether group (-SR ¹ ); and (A2) at least one amine group ( -NH ₂ , -NHR ² or -NR ³ R ⁴ ), wherein R ¹ , R ² , R ³ and R ⁴ are each independently alkyl, aryl, alkaryl or aralkyl. More preferably, (A) is an amino acid comprising at least one thiol group (-SH) or a thioether group (-SR ¹ ) or a derivative of the amino acid, wherein R ¹ is an alkyl group, an aryl group, Alkaryl or aralkyl. Most preferably, (A) is an amino acid comprising at least one thiol group (-SH) or a derivative of such an amino acid. Specifically, (A) is an amino acid containing a thiol group (-SH) or a derivative of the amino acid. Particularly preferably, (A) is cysteine, cysteine, glutathione, N-acetylcysteine or a derivative thereof. For example, (A) is cysteine or N-acetylcysteine.

R ¹ may generally be any substituted or unsubstituted alkyl, aryl, alkaryl or aralkyl group. R ^{1 is} preferably an alkyl group, more preferably an unsubstituted alkyl group, most preferably a C ₁ to C ₂₀ alkyl group, especially a C ₁ to C ₁₀ alkyl group such as a C ₁ to C ₄ alkyl group.

R ² may generally be any substituted or unsubstituted alkyl, aryl, alkaryl or aralkyl group. R ^{2 is} preferably an alkyl group, more preferably an unsubstituted alkyl group, most preferably a C ₁ to C ₂₀ alkyl group, especially a C ₁ to C ₁₀ alkyl group such as a C ₁ to C ₄ alkyl group.

R ³ may generally be any substituted or unsubstituted alkyl, aryl, alkaryl or aralkyl group. R ^{3 is} preferably an alkyl group, more preferably an unsubstituted alkyl group, most preferably a C ₁ to C ₂₀ alkyl group, especially a C ₁ to C ₁₀ alkyl group such as a C ₁ to C ₄ alkyl group.

R ⁴ may generally be any substituted or unsubstituted alkyl, aryl, alkaryl or aralkyl group. R ^{4 is} preferably an alkyl group, more preferably an unsubstituted alkyl group, most preferably a C ₁ to C ₂₀ alkyl group, especially a C ₁ to C ₁₀ alkyl group, for example a C ₁ to C ₄ alkyl group.

The total amount of NH ₄ ⁺ , any sulfur-free organic ammonium ion and any sulfur-free amine contained in the composition (Q) is not more than 100 ppm, preferably 40 ppm, more preferably 10 ppm, and the best 1 Ppm, particularly preferably 0.1 ppm, specifically 0.01 ppm (based on the total weight of the composition (Q)). For example, the composition (Q) does not contain any NH ₄ ⁺ or any sulfur-free organic ammonium ion or any sulfur-free amine. "Sulfur-free" means that the compound does not contain any covalently bonded sulfur atoms. "Organic ammonium ion" means a primary, secondary, tertiary or quaternary ammonium ion.

According to the invention, the composition (Q) comprises an aqueous medium (B). (B) may be an aqueous medium or a mixture of different types of aqueous medium.

Generally, the aqueous medium (B) can be any medium containing water. Preferably, the aqueous medium (B) is a mixture of water and a water-miscible organic solvent such as an alcohol, preferably a C ₁ to C ₃ alcohol or an alkanediol derivative. More preferably, the aqueous medium (B) is water. Most preferably, the aqueous medium (B) is deionized water.

If the total content of the components other than (B) is y wt% of the composition (Q), the (B) content is (100-y)% by weight of the composition (Q).

The composition (Q) may additionally contain at least one metal corrosion inhibitor (C) (preferably a metal corrosion inhibitor (C)) as needed. Typically, a metal corrosion inhibitor for a post-CMP cleaning composition reduces the rate of corrosion of the metal or alloy by, for example, forming a protective passivation layer on the surface of the metal or alloy when added to the composition. Compound.

Preferably, the metal corrosion inhibitor (C) does not have a nitrogen-containing functional group (eg, an amine group, a guanamine group, a guanidino group, a fluorenyl group, a hydroxylamine group, a urethane group, a triazolyl group, a tetrazolyl group and a similar nitrogen-containing functional group) and a compound derived from the cationic group of the nitrogen-containing functional group. Preferably, a metal corrosion inhibitor (C) which prevents copper corrosion (i.e., a copper corrosion inhibitor (C)) is used.

Typically, the composition (Q) may comprise varying levels of the metal corrosion inhibitor (C) and the content or concentration of (C) may be most advantageously adjusted in accordance with the particular requirements of the specified compositions, uses and methods of the invention. Preferably, the (C) content is not more than 1.5% by weight, more preferably not more than 0.5% by weight, most preferably not more than 0.2% by weight, particularly not more than 0.1% by weight, for example not more than 0.06% by weight (based on the composition ( Q) Total weight). Preferably, the (C) content is at least 0.0005 wt%, more preferably at least 0.001 wt%, optimally at least 0.007 wt%, in particular at least 0.02 wt%, such as at least 0.04 wt% (based on the composition (Q) Total weight).

More preferably, the metal corrosion inhibitor (C) is selected from the group consisting of water-soluble and water-dispersible (preferably water-soluble) having at least two (optimally at least three) hydroxyl groups (-OH) which are not dissociated in an aqueous medium. a group of compounds.

"Dissociate" means a hydroxyl group in the aqueous phase of the reaction ^{R-OH → RO - + H} + dissociation constant of the low-based or (in terms of actual object) is essentially zero.

Even more preferably, the metal corrosion inhibitor (C) is selected from the group consisting of polyols having at least two hydroxyl groups, polyhydric phenols, and carboxylic acids.

Preferably, the polyol (C) is selected from the group consisting of glycerin, trimethylolpropane, pentaerythritol, aldols, cyclic polyols, carbohydrates and glycerol, trimethylolpropane, pentaerythritol, aldehydes. A group consisting of a dimer and an oligomer of an alcohol and a cyclic polyol.

More preferably, the aldol (C) is selected from the group consisting of butanol, pentitol, hexitol, heptitol, and octitol.

Even more preferably, the butanol (C) is selected from the group consisting of erythritol, threitol, and stereoisomers and mixtures thereof; the pentitol (C) is selected from the group consisting of arabitol, ribitol, and wood. a group consisting of a sugar alcohol and a stereoisomer thereof and a mixture thereof; the hexitol (C) is selected from the group consisting of galactitol, mannitol, glucose alcohol, garlic alcohol, altitol, iditol and its stereo a group of isomers and mixtures.

Even more preferably, the dimer (C) is selected from the group consisting of dimers of glycerol, trimethylolpropane, erythritol, threitol and pentaerythritol, and stereoisomers and mixtures thereof, and maltose A group of alcohols, isomalt, lactitol, and stereoisomers and mixtures thereof.

Particularly preferably, the oligomer (C) is selected from the group consisting of tri-, tetra-, five-, six-, seven-, eight-, nine-, ten-, eleven- and twelve-glycerol,-tris-hydroxyl A group consisting of propane, erythritol, threitol, and isopentaerythritol, and stereoisomers and mixtures thereof.

Even more preferably, the cyclic polyols (C) are selected from the group consisting of 1,2,3,4-tetrahydroxycyclohexane, 1,2,3,4,5-pentahydroxycyclohexane, inositol and Stereoisomers and mixtures.

Even more preferably, the inositol (C) is selected from the group consisting of muscle-, shark-, mucilage-, palmar-, neo-, iso-, epi- and cis inositol and mixtures thereof. Optimally, muscle myoinositol (C) is used.

Even more preferably, the carbohydrate (C) is selected from the group consisting of monosaccharides.

Particularly preferably, the monosaccharide (C) is selected from the group consisting of allose, altrose, glucose, mannose, idose, galactose and talose, specific It is galactose.

Even more preferably, the polyhydric phenol (C) is selected from the group consisting of pyrocatechol, resorcinol, hydrogen A group consisting of guanidine, pyrogallol, 1,2,4-nonylhydroxybenzene and phloroglucinol.

More preferably, the carboxylic acid (C) having at least two hydroxyl groups is selected from the group consisting of a sugar acid having at least two hydroxyl groups and a benzenecarboxylic acid. Even more preferably, the sugar acid (C) is selected from the group consisting of glyceric acid, tartaric acid, threonic acid, erythric acid, xylic acid, glucuronic acid, ascorbic acid, gluconic acid, galacturonic acid, idose A group consisting of aldehyde acid, mannuronic acid, glucuronic acid, guluronic acid, uronic acid, glucaric acid, ketonic acid, lactobionic acid, and mixtures thereof.

Even more preferably, the benzenecarboxylic acid (C) is selected from the group consisting of 2,3-, 2,4-, 2,5-, 2,6-, 3,4- and 3,5-dihydroxybenzoic acid and 2 a group consisting of 4,6-, 2,4,5-, 2,3,4- and 3,4,5-trihydroxybenzoic acid (gallic acid).

Most preferably, erythritol or a stereoisomer thereof or gallic acid is used as the metal corrosion inhibitor (C). For example, erythritol or a stereoisomer thereof is used as the metal corrosion inhibitor (C).

The composition (Q) may additionally contain at least one metal chelating agent (D) (preferably a metal chelating agent (D)) as needed. Typically, metal chelators used in post-CMP cleaning compositions are compounds which form soluble miscible molecules with certain metal ions which passivate the plasma so that it does not react normally with other elements or ions to form a precipitate or product. dirt.

Typically, the composition (Q) may comprise varying levels of the metal chelating agent (D) and the content or concentration of (D) may be most advantageously adjusted in accordance with the particular requirements of the specified compositions, uses and methods of the invention. Preferably, the (D) content is not more than 1.5% by weight, more preferably not more than 0.5% by weight, most preferably not more than 0.2% by weight, especially not more than 0.1% by weight, for example not more than 0.06% by weight (based on the composition ( Q) Total weight). Preferably, the (D) content is at least 0.0005 wt%, more preferably at least 0.001 wt%, optimally at least 0.007 wt%, especially at least 0.02 wt%, such as at least 0.04 wt% (based on the total weight of the composition (Q)) meter).

Preferably, the metal chelating agent (D) system comprising at least two carboxylic acid groups (-COOH) or carboxylate (-COO ^-) of the compound. More preferably, (D) a carboxylic acid group comprises at least three lines (-COOH) or carboxylate (-COO ^-) of the compound. Most preferably, the metal chelating agent (D) is selected from the group consisting of: (D1) propane-1,2,3-tricarboxylic acid; (D2) citric acid; (D3) butane-1,2, 3,4-tetracarboxylic acid; (D4) pentane-1,2,3,4,5-pentacarboxylic acid; (D5) trimellitic acid; (D6) trimesic acid; (D7) pyromelli Formic acid; (D8) mellitic acid; and (D9) oligomeric and polymeric polycarboxylic acid.

Particularly preferably, (D) is selected from the group consisting of (D1), (D2), (D3), (D4), (D5), (D6), (D7), and (D8). Specifically, (D) is selected from the group consisting of (D1), (D2), (D3), and (D4). For example, the metal chelating agent (D) is citric acid (D2).

In the embodiment wherein the metal chelating agent (D) is (D9), (D9) is preferably an oligomeric or polymeric polycarboxylic acid comprising acrylic acid and/or methacrylic acid (preferably acrylic acid) monomer units. The weight average molecular weight of (D9) as measured by gel permeation chromatography is preferably less than 20,000 Daltons, more preferably less than 15,000 Daltons, most preferably less than 10,000 Daltons, especially less than 5,000 Daltons. It is preferably greater than 500 Daltons, more preferably greater than 1,000 Daltons, and most preferably greater than 2,000 Daltons, especially greater than 2,500 Daltons. (D9) may be a homopolymer (i.e., polyacrylic acid or polymethacrylic acid (preferably polyacrylic acid) homopolymer) or a copolymer. The copolymer comprising the acrylic monomer units may comprise substantially any other suitable monomer unit, preferably a monomer unit comprising at least one carboxylic acid group, in particular derived from fumaric acid, maleic acid, Monomeric units of itaconic acid, aconitic acid, mesaconic acid, citraconic acid, methylenemalonic acid or maleic anhydride. Most preferably, the copolymer is a maleic acid/acrylic acid copolymer. For example, the copolymer is Sokalan ^® CP 12 S.

The oligomeric polycarboxylic acid is a polycarboxylic acid having at least 7 carboxylic acid groups. Polymeric polycarboxylic acid A polycarboxylic acid having at least 30 carboxylic acid groups.

The composition (Q) may additionally comprise at least one surfactant (E), preferably a surfactant (E), more preferably from a water-soluble or water-dispersible (preferably water-soluble) amphoteric nonionic interface. A surfactant (E) of the group of active agents (E1), (E2) and (E3).

Typically, surfactants used in post-CMP cleaning compositions are surface-active compounds that reduce the surface tension of the liquid, the interfacial tension between the two liquids, or the interfacial tension between the liquid and the solid.

Typically, the composition (Q) may comprise varying levels of the surfactant (E) and the content or concentration of (E) may be most advantageously adjusted in accordance with the particular requirements of the specified compositions, uses and methods of the invention. Preferably, the (E) content is not more than 5% by weight, more preferably not more than 2% by weight, most preferably not more than 1% by weight, especially not more than 0.5% by weight, for example not more than 0.3% by weight (based on the composition ( Q) Total weight). Preferably, the (E) content is at least 0.0005 wt%, more preferably at least 0.005 wt%, most preferably at least 0.01 wt%, especially at least 0.05 wt%, such as at least 0.1 wt% (based on the total weight of the composition (Q) meter).

The amphoteric nonionic surfactant (E1) comprises at least one hydrophobic group (e11). This means that (E1) may have more than one hydrophobic group (e11) (for example, 2, 3 or more groups (e11) which are separated from each other by at least one hydrophilic group (e12) described below).

The hydrophobic group (e11) is selected from the group consisting of branched alkyl groups having 5 to 20 (preferably 7 to 16, preferably 8 to 15) carbon atoms.

Preferably, the branched alkyl group (e11) has an average degree of branching of from 1 to 5 (preferably from 1 to 4, most preferably from 1 to 3).

Suitable branched alkyl groups (e11) are derived from isopentane, neopentane and branched hexane, heptane, octane, decane, decane, undecane, dodecane, tridecane, ten Tetraline, pentadecane, hexadecane, heptadecane, nonadecane and eicosane isomers.

Most preferably, the branched alkyl groups (e11) are derived from Guerbet-alcohol having 8 to 15 (preferably 10) carbon atoms (refer to Römpp Online 2011, "Guerbet-Reaktion").

(E1) contains at least one hydrophilic group (e12). This means that (E1) may contain more than one group (e12) (for example, 2, 3 or more groups (e12) which are separated from each other by the hydrophobic group (e11).

The hydrophilic groups (e12) are composed of oxygen-extended ethyl monomer units. The degree of polymerization of the hydrophilic groups (e12) can vary widely and thus can be most advantageously adjusted in accordance with the specific requirements of the specified compositions, uses and methods of the present invention. Preferably, the degree of ethoxylation is in the range of 4 to 20 (more preferably 6 to 16 and most preferably 7 to 8).

(E1) may have a different block-like structure. Examples of such block-like structures are: - e11-e12; - e11-e12-e11; - e12-e11-e12; - e12-e11-e12-e11; - e11-e12-e11-e12-e11 ; and - e12-e11-e12-e11-e12.

Most preferably, the block-like general structure e11-e12 is used.

Preferably, the weight average molecular weight of (E1) is in the range of 300 to 800 Daltons, preferably 400 to 750 Daltons, and most preferably 400 to 600 Daltons (measured by size exclusion chromatography). Inside.

Preferably, the hydrophilic-lipophilic balance (HLB) value is in the range of 8 to 16 (preferably 9 to 15 and most preferably 11 to 14).

Such amphiphilic nonionic surfactant (E1) based commonly known material and commercially available under the trademark Lutensol ^® from BASF SE. In particular, (E1) is Lutensol ^® XP80 or Lutensol ^® XP70, such as Lutensol ^® XP80.

The amphoteric nonionic surfactant (E2) also comprises at least one hydrophobic group (e21) and at least A hydrophilic group (e22).

This means that the amphoteric nonionic surfactant (E2) comprises more than one group (e22) (eg 2, 3 or more groups (e22), which are separated from each other by a hydrophobic group (e21)) or It contains more than one group (e22) (for example 2, 3 or more groups (e22) which are separated from each other by a hydrophobic group (e21)).

The amphoteric nonionic surfactant (E2) can have a different block-like structure. Examples of such block-like structures are: - e21-e22; - e21-e22-e21; - e22-e21-e22; - e22-e21-e22-e21; - e21-e22-e21-e22-e21 ; and - e22-e21-e22-e21-e22.

Most preferably, the block-like general structure e21-e22 is used.

Preferably, the above hydrophobic group (e11) is used as the hydrophobic group (e21).

The hydrophilic group (e22) contains an oxygen-extended ethyl monomer unit (e221).

Further, the hydrophilic group (e22) comprises at least one substituted alkylene oxide monomer unit (e222), wherein the substituents are selected from the group consisting of alkyl groups, cycloalkyl groups, aryl groups, alkyl-cycloalkyl groups, A group consisting of an alkyl-aryl group, a cycloalkyl-aryl group, and an alkyl-cycloalkyl-aryl group.

Preferably, the alkylene monomer units (e222) are derived from substituted ethylene oxides wherein the substituents are selected from the group consisting of alkyl, cycloalkyl, aryl, alkyl-naphthenes a group consisting of an alkyl group, an alkyl-aryl group, a cycloalkyl-aryl group, and an alkyl-cycloalkyl-aryl group.

The substituents of the ethylene oxide are selected from the group consisting of alkyl groups having from 1 to 10 carbon atoms; rings having from 5 to 10 carbon atoms in a spiro, out-of-loop and/or annealed configuration. An alkyl group; an aryl group having 6 to 10 carbon atoms; an alkyl-cycloalkyl group having 6 to 20 carbon atoms; an alkyl-aryl group having 7 to 20 carbon atoms; having 11 to 20 carbon atoms Cycloalkane a aryl-aryl group and an alkyl-cycloalkyl-aryl group having 12 to 30 carbon atoms.

Examples of suitable alkyl groups are methyl, ethyl, propyl, isopropyl, n-butyl, n-pentyl and n-hexyl. Examples of suitable cycloalkyl groups are cyclopentyl and cyclohexyl. Examples of suitable aryl groups are phenyl and 1- and 2-naphthyl.

Examples of particularly preferred substituted ethylene oxides are methyloxirane (propylene oxide) and ethyloxirane (butylene oxide).

Preferably, the hydrophilic group (e22) is composed of monomer units (e221) and (e222).

The polyoxyalkylene group comprises monomer units (e221) and (e222) in a random, alternating, gradient and/or block distribution. This means that a hydrophilic group (e22) has only one distribution, namely: - random: ...-e221-e221-e222-e221-e222-e222-e222-e221-e222-...;- alternating:. ..-e221-e222-e221-e222-e221-...;- Gradient: ...e221-e221-e221-e222-e221-e221-e222-e222-e221-e222-e222-e222-... ; or - Block: ...-e221-e221-e221-e221-e222-e222-e222-e222-...

Alternatively, the hydrophilic group (e22) may comprise at least two distributions, such as oligomeric or polymeric blocks having a random distribution and oligomeric or polymeric blocks having an alternating distribution.

Preferably, the hydrophilic group (e22) has only one distribution. Most preferably, the distribution is random or block type.

The molar ratio of the oxygen-extended ethyl monomer unit (e221) to the oxygen-extended alkyl monomer unit (e222) can vary widely and can therefore be most advantageously adjusted according to the specific requirements of the specified compositions, uses and methods of the present invention. . Preferably, the molar ratio (e221): (e222) is from 100:1 to 1:1, more preferably from 60:1 to 1.5:1 and most preferably from 50:1 to 1.5:1.

The degree of polymerization of the oligomeric or polymeric polyoxyalkylene groups (e22) can also vary widely and thus can be most advantageously adjusted in accordance with the particular requirements of the specified compositions, methods and uses of the present invention. Preferably, the degree of polymerization is in the range of 5 to 100 (more preferably 5 to 90 and most preferably 5 to 80).

Such amphiphilic nonionic surfactant (E2) based material and commonly known under the trademark Plurafac ^TM from BASF SE or the trademark Triton ^TM commercially available from Dow.

The amphoteric nonionic surfactant (E3) is an alkyl polyglucoside (APG). The APG preferably has an average degree of polymerization of from 1 to 5 (preferably from 1.2 to 1.5). Preferably, the alkyl group of the APG has from 8 to 16 carbon atoms and most preferably from 12 to 14 carbon atoms. The APG-based material and commonly known under the trademark Glucopon ^TM commercially available from Cognis.

Preferably, the surfactant (E) is selected from the group consisting of: (E1) an amphoteric nonionic water-soluble or water-dispersible surfactant having: (e11) selected from the group consisting of having 5 to 20 carbons At least one hydrophobic group of a group consisting of a branched alkyl group of atoms; and (e12) at least one hydrophilic group composed of an oxygen-extended ethyl monomer unit; (E2) an amphoteric nonionic water-soluble or water-dispersible surfactant And having (e21) at least one hydrophobic group selected from the group consisting of branched alkyl groups having 5 to 20 carbon atoms; and (e22) selected from the group consisting of polyoxyalkylene groups including the following At least one hydrophilic group: (e221) an oxygen-extended ethyl monomer unit; and (e222) at least one substituted oxygen alkyl unit monomer, wherein the substituents are selected from the group consisting of alkyl groups, cycloalkyl groups, and aryl groups a group consisting of an alkyl-cycloalkyl group, an alkyl-aryl group, a cycloalkyl-aryl group, and an alkyl-cycloalkyl-aryl group; the polyoxyalkylene group of (e22) comprises a random, alternating group , gradient and/or block distribution of monomer units (e221) and (e222); and (E3) amphoteric nonionic water-soluble or water-dispersible alkyl polyglucoside boundaries Surfactant.

More preferably, the surfactant (E) is: (E1) an amphoteric nonionic water-soluble or water-dispersible surfactant having: (e11) selected from a branched alkyl group having 5 to 20 carbon atoms At least a group a hydrophobic group; and (e12) at least one hydrophilic group consisting of oxygen-extended ethyl monomer units.

The properties of the composition (Q) and the method (P) (e.g., general cleaning performance and passivation film removal efficiency) may depend on the pH of the corresponding composition. The pH of the composition (Q) is preferably at least 2, more preferably at least 3, most preferably at least 4, especially at least 5, such as at least 5.5. The pH of the composition (Q) is preferably not more than 11, more preferably not more than 10, most preferably not more than 9, particularly preferably not more than 8, especially not more than 7, such as not more than 6.5.

The composition (Q) may additionally comprise at least one pH adjusting agent (G) as needed. Typically, the pH adjusting agent (G) is added to the composition (Q) to adjust its pH to the desired value of the compound. Preferably, the composition (Q) comprises at least one pH adjusting agent (G). Preferred pH adjusting agents (G) are inorganic acids, carboxylic acids and alkali metal hydroxides. Specifically, the pH adjuster (G) is sulfuric acid, sodium hydroxide or potassium hydroxide. For example, the pH adjuster (G) is sulfuric acid or potassium hydroxide.

If the pH adjuster (G) is present, it may be present in different amounts. If (G) is present, its content is preferably not more than 10% by weight, more preferably not more than 2% by weight, most preferably not more than 0.5% by weight, especially not more than 0.1% by weight, for example not more than 0.05% by weight (based on the combination The total weight of the substance (Q)). If (G) is present, its content is preferably at least 0.0005 wt%, more preferably at least 0.005 wt%, most preferably at least 0.02 wt%, especially at least 0.1 wt%, such as at least 0.4 wt% (based on the composition (Q) Total weight).

If desired, the composition (Q) may also contain various other additives including, but not limited to, stabilizers, antifriction agents, biocides or preservatives, and the like. Such other additives are, for example, those commonly used in post-CMP cleaning compositions and are therefore known to those skilled in the art. This addition can, for example, stabilize or improve cleaning performance of such post-CMP cleaning compositions.

If these other additives are present, they may be present in different amounts. Preferably, the total amount of the other additives is not more than 10% by weight, more preferably not more than 2% by weight, most preferably not more than 0.5% by weight, especially not more than 0.1% by weight, for example not more than 0.01% by weight (based on The total weight of the composition (Q)). Preferably, the total amount of such other additives is at least 0.0001% by weight, more preferably at least 0.001% by weight, most preferably at least 0.008% by weight, especially at least 0.05% by weight, such as at least 0.3% by weight (based on the composition (Q) Total weight).

For the following preferred examples (PE1) to (PE19): (Ai) represents "containing at least one thiol group (-SH), thioether group (-SR ¹ ) or thiocarbonyl group (>C=S) and At least one amine group (-NH ₂ , -NHR ² or -NR ³ R ⁴ ) and wherein R ¹ , R ² , R ³ and R ⁴ are each independently alkyl, aryl, alkaryl or aralkyl "Compound"; (A-ii) stands for "cysteine, cystine, glutathione, N-acetylcysteine or its derivatives"; (Ci) stands for "having at least two in aqueous medium" (Ni) is a water-soluble compound that does not dissociate from the hydroxyl group (-OH); (Ni) stands for "NH ₄ ⁺ , any sulfur-free organic ammonium ion and any sulfur-free amine."

According to a preferred embodiment (PE1), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; and (C) (Ci); wherein (Ni) does not exceed 100 ppm (based on the combination The total weight of the substance (Q)).

According to another preferred embodiment (PE2), the composition (Q) comprises: (A) (A-ii); (B) an aqueous medium; and (C) (Ci); wherein (Ni) does not exceed 100 ppm (based on the total weight of the composition (Q)).

According to another preferred embodiment (PE3), the composition (Q) comprises: (A) (A-ii); (B) an aqueous medium; (C) a water-soluble compound having at least three hydroxyl groups (-OH) which are not dissociated in an aqueous medium; wherein (N-i) is not more than 10 ppm based on the total weight of the composition (Q).

According to another preferred embodiment (PE4), the composition (Q) comprises: (A) (A-ii); (B) an aqueous medium; and (C) having at least three hydroxyl groups which are not dissociated in an aqueous medium. (-OH) a water-soluble compound; wherein the composition (Q) does not contain NH ₄ ⁺ or any sulfur-free organic ammonium ion or any sulfur-free amine.

According to another preferred embodiment (PE5), the composition (Q) comprises: (A) (A-ii); (B) an aqueous medium; and (C) erythritol or a stereoisomer thereof or Gallic acid; wherein (Ni) does not exceed 100 ppm (based on the total weight of the composition (Q)).

According to another preferred embodiment (PE6), the composition (Q) comprises: (A) thiourea or a derivative thereof; (B) an aqueous medium; and (C) (Ci); wherein (Ni) does not exceed 100 Ppm (based on the total weight of the composition (Q)).

According to another preferred embodiment (PE7), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; and (C) (Ci); wherein (Ni) does not exceed 100 ppm (based on The total weight of the composition (Q) and wherein the composition (Q) has a pH of from 4 to 8.

According to another preferred embodiment (PE8), the composition (Q) comprises: (A) (A-ii); and (B) an aqueous medium; wherein (Ni) does not exceed 100 ppm (based on the composition (Q) The total weight of the compound) and wherein the composition (Q) has a pH of from 4 to 8.

According to another preferred embodiment (PE9), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; and (D) a metal chelating agent selected from the group consisting of propane-1,2, 3-tricarboxylic acid, citric acid, butane-1,2,3,4-tetracarboxylic acid, pentane-1,2,3,4,5-pentacarboxylic acid, trimellitic acid, trimesic acid a group consisting of pyromellitic acid, mellitic acid, and oligomeric and polymeric polycarboxylic acids; wherein (Ni) does not exceed 100 ppm (based on the total weight of the composition (Q)).

According to another preferred embodiment (PE10), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; (D) citric acid; wherein (Ni) does not exceed 100 ppm (based on the combination The total weight of the substance (Q)).

According to another preferred embodiment (PE11), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; and (D) an oligomeric or polymeric polycarboxylic acid; wherein (Ni) does not exceed 100 ppm based on the total weight of the composition (Q).

According to another preferred embodiment (PE12), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; (D) an oligomer comprising acrylic acid and/or methacrylic monomer units or Polymeric polycarboxylate Acid; wherein (N-i) does not exceed 100 ppm (based on the total weight of the composition (Q)).

According to another preferred embodiment (PE13), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; and (D) a maleic acid/acrylic acid copolymer; wherein (Ni) does not exceed 100 ppm based on the total weight of the composition (Q).

According to another preferred embodiment (PE14a), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; (D) a metal chelating agent; and (E) a surfactant; Not more than 100 ppm based on the total weight of the composition (Q).

According to another preferred embodiment (PE14b), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; (D) an oligomeric or polymeric polycarboxylic acid comprising acrylic monomer units; (E) a surfactant; wherein (Ni) does not exceed 100 ppm (based on the total weight of the composition (Q)).

According to another preferred embodiment (PE14c), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; (D) an oligomeric or polymeric polycarboxylic acid comprising acrylic monomer units; (E) a water-soluble amphoteric nonionic surfactant; wherein the composition (Q) does not comprise NH ₄ ⁺ or any sulfur-free organic ammonium ion or any sulfur-free amine.

According to another preferred embodiment (PE15), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; (C) (Ci); (D) a metal chelating agent; and (E) a surfactant; wherein (Ni) does not exceed 100 ppm (based on the total weight of the composition (Q)).

According to another preferred embodiment (PE16), the composition (Q) comprises: (A) (A-ii); (B) an aqueous medium; (C) (Ci); (D) a metal chelating agent; E) a surfactant; wherein (Ni) does not exceed 100 ppm (based on the total weight of the composition (Q)) and wherein the composition has a pH of 4 to 8.

According to another preferred embodiment (PE17), the composition (Q) comprises: (A) (A-ii); (B) an aqueous medium; (C) (Ci); (D) as a metal chelating agent. at least three carboxylic acid groups (-COOH) or carboxylate (-COO ^-) of the compound; and (E) water-soluble amphoteric nonionic surfactant; wherein the (Ni) of not more than 100 ppm (based on the composition ( Q) the total weight) and wherein the composition has a pH of 4 to 8.

According to another preferred embodiment (PE18), the composition (Q) comprises: (A) (Ai); (B) an aqueous medium; (C) (Ci); (D) a metal chelating agent; and (E) a surfactant; wherein the composition (Q) does not comprise NH ₄ ⁺ or any sulfur-free organic ammonium ion or any sulfur-free amine.

According to another preferred embodiment (PE19), the composition (Q) comprises: (A) (A-ii); (B) an aqueous medium; (C) (Ci); (D) as a metal chelating agent. at least three carboxylic acid groups (-COOH) or carboxylate (-COO ^-) of the compound; and (E) water-soluble amphoteric nonionic surfactant; wherein the (Ni) of not more than 100 ppm (based on the composition ( The total weight of Q), the contents of (A), (C), and (D) are each independently from 0.001% by weight to 0.5% by weight based on the total weight of the composition (Q), and the content of (E) is The total weight of the composition (Q) is from 0.005% by weight to 2% by weight.

The method of preparing the composition (Q) does not show any particularity, but can dissolve or disperse the above components (A) and (C) and optionally (D) and/or (E) and/or other additives. It is carried out in an aqueous medium (B) (specifically, deionized water and optimal ultrapure water). For this purpose, conventional standard mixing methods and mixing devices (such as stirred tanks, in-line dissolvers, high shear impellers, ultrasonic mixers, homogenizer nozzles or countercurrent mixers) can be used.

Various conventional cleaning tools and methods can be used for the method (P) or for applying the composition (Q) in a post-CMP cleaning step. Such cleaning tools include ultra high frequency sonic cleaners, brush cleaners, and combinations thereof. Typically, the brushes are made of a soft and porous polyvinyl alcohol material. The brushes can have different shapes depending on the manufacturer of the processing tool. most Common shapes are rollers, discs and pencils.

After contacting the semiconductor substrates with the composition (Q), the semiconductor substrates are removed from the composition and allowed to dry. This drying step can be carried out as described in, for example, U.S. Patent Application No. US 2009/02191873 A1, page 4, paragraph [0022].

The cleaning or removal properties (i.e., the removal of residues and contaminants) of the composition (Q) and the method (P) can be determined according to various methods. Preferably, the performance is evaluated by comparing the untreated semiconductor surface to the respective semiconductor surfaces that have been treated with the composition (Q) and the method (P). To this end, scanning electron microscopy (SCM) and/or atomic force microscopy (AFM) can be performed and the images obtained from the treated and untreated semiconductor surfaces can be compared to each other.

Examples and comparative examples

Ludox ^® TM50 is a colloidal vermiculite in the form of a 50% by weight suspension in H ₂ O and is obtained from Sigma-Aldrich.

Lutensol ^® XP80 is a branched-chain amphoteric nonionic surfactant supplied by BASF SE. It is based on an alkyl polyglycol ether of C ₁₀ - Guerbet alcohol and ethylene oxide.

Sokalan ^® CP 12 S is a polymeric polycarboxylic acid supplied by BASF SE. It is a maleic acid/acrylic acid copolymer.

The "immersion test" was performed using an electrochemically plated copper coupon. In the following step, the vermiculite slurry consisted of 0.5% by weight of Ludox ^® TM50 (pH 4). The first coupon was immersed in a 0.02 wt% HNO ₃ in 35 seconds, rinsed with deionized water and subsequently immersed in the slurry Silica 5 minutes followed by rinsing with deionized water for 15 seconds. Each coupon was then immersed in the bulk surfactant solution for 2 minutes and rinsed with deionized water for 15 seconds. The coupons are suspended so that they are air dried under ambient conditions. The residual vermiculite abrasive signs of the dried coupons were evaluated by scanning electron microscopy (SEM). Compare the dried coupons.

SEM images were recorded at a 15 kV accelerating potential and 50,000 magnification using a JEOL 7400 high resolution field emission scanning electron microscope.

Use pH electrode (Schott, blue line, pH0-14/-5...100°C/3 mol/L sodium chloride) The amount of pH.

Contact angle measurement

The contact angle of deionized water (deionized water is referred to as "DIW" hereinafter) on the surface of the treated and untreated copper wafer was measured. The electrochemically plated copper wafer copper surface without any treatment has a DIW contact angle of about 80°, which means that organic residues are adsorbed on the copper surface. The copper coupon was immersed in 0.02% by weight of HNO ₃ for 35 seconds and washed with DIW to obtain a fresh surface. The new copper surface has a DIW contact angle of about 50°, which indicates that the surface is relatively hydrophilic. The HNO ₃ pretreated copper coupon was then immersed in a 0.2 wt% benzotriazole solution (benzotriazole hereinafter referred to as "BTA") for 5 minutes, rinsed by DIW and subjected to compressed air drying. The Cu-BTA surface has a DIW contact angle of about 89°, which indicates that the surface is relatively hydrophobic (i.e., non-wetting). The Cu-BTA surface was immersed in the various compositions listed in Table A for 5 minutes, rinsed with DIW for 15 seconds and then subjected to compressed air drying for 1 minute, after which the contact angle of DIW was measured immediately. For comparison, the DIW contact angle on the surface of the new copper treated with the same composition was also determined. The surface structures tested are summarized in Table A below.

It can be seen that the Cu-BTA surfaces treated with citric acid, serine, and urea have contact angles of about 64, 75, and 67, respectively, indicating that the treated surfaces are still relatively hydrophobic. Conversely, the surface of the new Cu treated with citric acid, serine, and urea has 41°, 46°, and 38°, respectively. The contact angle at which the treated surfaces are hydrophilic. However, both the cysteine-treated Cu-BTA surface and the nascent Cu surface had a DIW contact angle of about 34° and 32°. Interestingly, the Cu-BTA surface treated with acetaminosamine had a DIW contact angle of 43° which was identical to the surface of the new copper treated with acetaminosamine. Similarly, the thiourea-treated Cu-BTA surface has a DIW contact angle of about 63° which is similar to the DIW contact angle on the thiourea-treated new copper surface. These results show that the Cu-BTA and the nascent copper surface will have nearly the same DIW contact angle after treatment with a composition containing a compound comprising at least one thiol group, thioether group or thiocarbonyl group.

Tafel plot measurement of cleaning efficiency of BTA film on copper surface

The cleaning efficiency of the BTA film on the Cu surface was evaluated by Tafel curve measurement. The nascent Cu wafer coupon was immersed in a 0.2% BTA solution having a neutral pH of 5.8 for 15 minutes, rinsed by DIW and then dried by compressed air. As a working electrode (relative to the Ag/AgCl reference electrode), a BTA-treated copper coupon was immersed in various compositions for measurement. For comparison, fresh copper coupons were also immersed in various compositions for measurement. The corrosion potential and corrosion current of the substrates contained in different solutions are summarized in Table B below.

It can be seen that the corrosion current of copper treated with 0.2% by weight of BTA in DIW (pH 6) is 0.018 μA/cm ² , which is much lower than the corrosion current of the new copper contained in the same solution, indicating that the BTA film is on the Cu surface. High passivation efficiency. As a chelating agent, the corrosion current of the new copper contained in citric acid and serine is much higher than the corrosion current of copper contained in the blank solution (DIW pH 6). However, the corrosion current of the Cu-BTA surface contained in citric acid and serine is lower than that of the Cu surface contained in the same solution, but is relatively higher than that of the Cu-BTA surface contained in the blank solution. At the same time, the corrosion potential of Cu-BTA is higher than that of Cu, which means that citric acid and serine can remove a certain amount of BTA layer, but there is still a BTA film on the copper surface. Conversely, the corrosion current of Cu-BTA contained in the acetaminophen, cysteine, and thiourea solutions is almost equal to the corrosion current of the Cu surface contained in the same solution, indicating Cu-BTA film. Complete removal of these solutions. In another aspect, the BTA removal efficiency can be simply predicted by measuring the corrosion potential and corrosion current of the Cu-BTA and Cu surfaces.

XPS measurement of cleaning efficiency of BTA film on copper surface

The BTA removal efficiency of the formulation on the Cu substrate was evaluated. Wafer coupons were pretreated with 0.02 wt% HNO _{3 for} 35 seconds, rinsed with DIW and then compressed air dried. The coupon was then immersed in a 0.2 wt% BTA solution for 5 minutes, then rinsed with DIW and air dried. Thereafter, the BTA-treated copper coupon was immersed in various formulations (pH 6) for 5 minutes, rinsed with DIW and then dried by compressed air. BTA treated and untreated samples were analyzed for comparison. Analysis was performed using X-ray photoelectron spectroscopy (XPS) at an angle of 55°. Table C includes BTA removal results in different composition solutions relative to BTA and untreated samples.

The nitrogen to copper ratio indicates the BTA content remaining on the copper surface. As expected, citric acid and serine can remove a portion of the BTA layer, but BTA remains on the surface of the wafer. Conversely, compounds containing at least one thiol, thioether or thiocarbonyl group (eg, acetaminos, cysteine, and thiourea) have high BTA removal efficiencies.

No. 1 immersion test

Tests were conducted to evaluate the relative cleaning performance of the different formulations listed in Table D. The copper coupons were immersed in a 0.02 wt% HNO ₃ in 35 seconds, and then rinsed with DIW and dried with compressed air. The coupon was immersed in a 0.2 wt% BTA 5 minutes, rinsed with the DIW, after the surface of the Cu-BTA immersed in a 0.5 wt% Ludox ^® TM 50 (pH4) for 5 minutes. The coupon was then immersed in the cleaning composition for 2 minutes, then rinsed with DIW and air dried. The control sample coupons for Z of 0.2 wt% BTA was immersed for 5 minutes, rinsed with the DIW, test specimens are then Cu-BTA surface of the block was immersed in a 0.5 wt% 50 (pH4) of Ludox ^® TM 5 minutes . No cleaning treatment was performed on the control sample Z. The SEM analysis results are summarized in Figure 1.

The results in Figure 1 show that the copper surface cleaned without a compound comprising at least one thiol group, thioether group or thiocarbonyl group still has a large amount of vermiculite particles on the surface, possibly due to the presence of adsorbed BTA on the Cu surface. Conversely, when using a compound containing at least one thiol group, thioether group or thiocarbonyl group (for example, cysteine or N-acetyl cystein) When the copper is washed, the amount of vermiculite particles is significantly reduced.

These cleaning compositions S32 and S33 show improved cleaning performance.

No. 2 immersion test

Tests were conducted to evaluate the cleaning performance of different cleaning compositions at different pH conditions. These test compositions were prepared as described in Table E. By adjusting dilute HNO ₃ or KOH all such compositions. The cleaning compositions prepared were evaluated using electrochemically plated copper wafers according to the following steps. The wafer is polished with a slurry comprising a barrier layer of vermiculite particles, H ₂ O ₂ , BTA. The polished wafer is then cut into coupons. The copper coupons were immersed in the cleaning composition for 5 minutes and then rinsed with DI water for 15 seconds, followed by compressed air drying for 1 minute. Signs of residual vermiculite abrasive and BTA passivation layers of the dried coupons were evaluated by scanning electron microscopy (SEM). For comparison, the unpolished polished sample block (control sample Y) was also evaluated by SEM. The results are shown in Figures 2 and 3.

The results in Figures 2 and 3 indicate that when the copper surface is cleaned by a cleaning composition containing a compound comprising at least one thiol group, thioether group or thiocarbonyl group (e.g., N-acetylcysteine), The vermiculite particles are completely removed. Conversely, the vermiculite particles are almost impossible to clean by a cleaning composition that does not contain the compound. These results show that there is a BTA passivation layer on the copper surface after the barrier CMP treatment, which will inhibit the removal of such vermiculite particles during cleaning. The results also indicate that the ones contain at least one thiol group, thioether group or sulfur The cleaning composition of the carbonyl compound (e.g., N-acetylcysteine) has good performance at pH 3.6 and 10.5. Accordingly, the post-CMP cleaning compositions of the present invention are suitable for use under acidic, neutral and basic conditions.

The cleaning compositions S35, S36, S37, S44, S45 and S46 show improved cleaning performance.

Claims (22)

A chemical mechanical polishing (post-CMP) cleaning composition comprising: (A) at least one compound comprising at least one thiol group (-SH), a thioether group (-SR ¹ ) or a thiocarbonyl group (>C =S), wherein R ¹ is an alkyl group, an aryl group, an alkylaryl group or an aralkyl group; and (B) an aqueous medium; wherein the composition comprises NH ₄ ⁺ , any sulfur-free organic ammonium ion and The total amount of any sulfur-free amine does not exceed 100 ppm based on the total weight of the composition. A post-CMP cleaning composition according to claim 1 wherein the composition does not comprise NH ₄ ⁺ or any sulfur-free organic ammonium ion or any sulfur-free amine. The composition of claim 1 or 2, wherein the compound (A) comprises at least one thiol group (-SH), a thioether group (-SR ¹ ) or a thiocarbonyl group (>C=S) and at least one amine group a compound of (-NH ₂ , -NHR ² or -NR ³ R ⁴ ), and wherein R ¹ , R ² , R ³ and R ⁴ are each independently alkyl, aryl, alkaryl or aralkyl. The composition of claim 1 or 2, wherein the compound (A) is a thiourea or a derivative thereof. The composition of claim 1 or 2, wherein the compound (A) is an amino acid comprising at least one thiol group (-SH) or a thioether group (-SR ¹ ) or a derivative of the amino acid, and Wherein R ¹ is an alkyl group, an aryl group, an alkylaryl group or an aralkyl group. The composition of claim 1 or 2, wherein the compound (A) is cysteine, cystine, glutathione, N-acetylcysteine or a derivative thereof. The composition of any one of claims 1 to 6, wherein the composition additionally comprises (C) at least one metal corrosion inhibitor. The composition of any one of claims 1 to 6, wherein the composition additionally comprises at least one metal corrosion inhibitor (C) selected from the group consisting of at least two in an aqueous medium A group of water-soluble and water-dispersible compounds composed of a non-dissociated hydroxyl group (-OH). The composition of any one of claims 1 to 6, wherein the composition further comprises at least one metal corrosion inhibitor (C) selected from the group consisting of butanol, pentitol, hexitol, heptitol, and Aldols of the group consisting of octanols. The composition of any one of claims 1 to 9, wherein the composition additionally comprises (D) at least one metal chelating agent. The composition of any one of claims 1 to 9, wherein the composition additionally comprises at least one metal chelating agent (D) selected from the group consisting of propane-1,2,3-tricarboxylic acid, citric acid, butane -1,2,3,4-tetracarboxylic acid, pentane-1,2,3,4,5-pentacarboxylic acid, trimellitic acid, trimesic acid, pyromellitic acid, mellitic acid and oligo A group of poly- and poly-polycarboxylic acid compositions. The composition of any one of claims 1 to 9, wherein the composition further comprises at least one metal chelating agent (D) which is an oligomeric and polymeric polycarboxylic acid comprising acrylic monomer units. The composition of any one of claims 1 to 12, wherein the composition additionally comprises (E) at least one surfactant. The composition of any one of claims 1 to 12, wherein the composition further comprises at least one surfactant (E) selected from the group consisting of: (E1) amphoteric nonionic water soluble or water dispersed a surfactant having: (e11) at least one hydrophobic group selected from the group consisting of branched alkyl groups having 5 to 20 carbon atoms; and (e12) at least one composed of oxygen-extended ethyl monomer units a hydrophilic group; (E2) an amphoteric nonionic water-soluble or water-dispersible surfactant having: (e21) at least one hydrophobic group selected from the group consisting of branched alkyl groups having 5 to 20 carbon atoms; (e22) at least one selected from the group consisting of polyoxyalkylene groups including the following a hydrophilic group: (e221) an oxygen-extended ethyl monomer unit; and (e222) at least one substituted oxygen alkyl unit monomer, wherein the substituents are selected from the group consisting of alkyl groups, cycloalkyl groups, aryl groups, a group consisting of an alkyl-cycloalkyl group, an alkyl-aryl group, a cycloalkyl-aryl group, and an alkyl-cycloalkyl-aryl group; the polyoxyalkylene group of (e22) comprises a random, alternating, Gradient and/or block distribution of monomer units (e221) and (e222); and (E3) amphoteric nonionic water-soluble or water-dispersible alkyl polyglucoside surfactants. Use of a cleaning composition as defined in any one of claims 1 to 14 for removing residues and contaminants from the surface of a semiconductor substrate used to fabricate a microelectronic device. The use of claim 15, wherein the cleaning composition has a pH of from 4 to 8. The use of claim 15, wherein the residue and contaminant comprise benzotriazole or a derivative thereof and wherein the surface is a copper-containing surface. The use of claim 15, wherein the cleaning composition is for removing residues and contaminants from a surface of a semiconductor substrate comprising the following layers after chemical mechanical polishing: a conductive layer comprising or consisting of copper; Or an electrically insulating dielectric layer composed of an ultra-low-k dielectric material; and comprising or consisting of tantalum, tantalum nitride, titanium nitride, cobalt, nickel, manganese, tantalum, tantalum nitride, tantalum carbide or tantalum nitride The barrier layer. A method of fabricating a microelectronic device from a semiconductor substrate, comprising: contacting the semiconductor substrate with the cleaning composition as defined in any one of claims 1 to 14 at least once to move from the surface of the semiconductor substrate Steps to remove residues and contaminants. The method of claim 19, wherein the cleaning composition has a pH of from 4 to 8. The method of claim 19, wherein the residues and contaminants comprise benzotriazole or a derivative thereof and wherein the surface is a copper-containing surface. The method of claim 19, wherein the semiconductor substrate comprises: a conductive layer comprising or consisting of copper; an electrically insulating dielectric layer composed of a low-k or ultra-low-k dielectric material; and comprising germanium, tantalum nitride, Titanium nitride, cobalt, nickel, manganese, tantalum, tantalum nitride, tantalum carbide or tantalum tungsten nitride or a barrier layer composed thereof.