Cleaning compositions and methods of use thereof

Abstract

The present disclosure relates to cleaning compositions that can be used to clean semiconductor substrates. The cleaning compositions can be used to remove defects resulting from processing steps previously performed on the semiconductor substrates. The cleaning compositions may remove defects / contaminants from the semiconductor substrates, thereby adapting the substrates for further processing. The cleaning compositions described herein include predominantly at least one organic acid and at least one anionic polymer.

Description

[0001] This application is a divisional application of the Chinese application with application number 202180028333.3 and filing date March 18, 2021.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority to U.S. Provisional Application No. 62 / 991,612, filed on March 19, 2020, the contents of which are incorporated herein by reference in their entirety. Background Art

[0004] The semiconductor industry continues to be driven by further device miniaturization through process and integration innovations to improve chip performance. Chemical mechanical polishing / planarization (CMP) is a powerful technology because it enables many complex transistor-level integration schemes, thereby facilitating increased chip density.

[0005] CMP is a process that planarizes the surface of a wafer by removing material using abrasion-based physical processes and surface-based chemical reactions. In general, a CMP process includes applying a CMP slurry (e.g., an aqueous chemical formulation) to the surface of a wafer while contacting the wafer surface with a polishing pad and moving the polishing pad relative to the wafer. The slurry typically includes an abrasive component and dissolved chemical components, which can vary widely depending on the materials present on the wafer that interact with the slurry and polishing pad during the CMP process (e.g., metals, metal oxides, metal nitrides, dielectric materials such as silicon oxide, silicon nitride, etc.).

[0006] After the CMP process, various contaminants may be present on the polished wafer surface. Contaminants may include, for example, particulate abrasives from the CMP slurry, organic residues from the pad or slurry components, and materials removed from the wafer during the CMP process. If these contaminants remain on the polished wafer surface, they may cause failures in further processing steps of the wafer and / or result in device performance degradation. Figure 1 Four different defect modes after CMP polishing are shown - scratches, residual abrasive, organic particles in the form of droplets, and organic particles in the form of dust.

[0007] Therefore, it is necessary to effectively remove these contaminants so that the wafer can be foreseeably processed further and / or achieve optimal device performance. The process of removing these polished contaminants or residues on the wafer surface after CMP is called post-CMP cleaning. The formulation used in this post-CMP cleaning process is called post-CMP (post-CMP, P-CMP) cleaning solution or composition. These P-CMP cleaning solutions / formulations are intended to dissolve the defects remaining on the wafer surface after the CMP step, thereby removing these defects and making the wafer surface clean. This further ensures that once the wafer is further processed, the device performance and chip yield are satisfactory.

[0008] The post-CMP cleaning process can be performed in a brush box (containing mechanically acted brushes) or a megasonic (mechanically acted advanced ultrasonic / sonic treatment) as an attachment / module to the CMP polishing tool. To begin the P-CMP cleaning process, the brush box or megasonic is flooded with the P-CMP cleaning composition. Thereafter, after the CMP polishing process is completed, the CMP polished wafer is passed through the brush box and / or megasonic in the CMP polishing tool containing the P-CMP cleaning composition. In the best case, after the wafer has been subjected to the chemical action of the post-CMP cleaning composition and the mechanical action of the brush and / or sonic treatment, the wafer comes out dry and clean with very low defectivity. Summary of the invention

[0009] In semiconductor chip manufacturing, the defectivity of the wafer surface is the key to determining the wafer yield. A typical wafer goes through about 1,000 processes before it is made into chips and individual dies are cut from the wafer. In each of these processes, defectivity is monitored before and after the process. CMP is an important step in chip manufacturing. However, the CMP step introduces many defects after the polishing step (see Figure 1 and Figure 2 ). Therefore, after the CMP polishing step, a post-CMP (P-CMP) cleaning composition is typically applied to the wafer surface to reduce defects (see Figure 2 The present disclosure features novel P-CMP cleaning compositions that not only reduce wafer defects but also provide various other advantageous electrochemical properties that are critical to chip manufacturing. For example, these P-CMP cleaning compositions not only reduce defectivity (thereby increasing yield), but also ensure that there is no electrochemical corrosion (or other forms of corrosion) when metals and metal oxides and nitrides are in contact with each other on a patterned wafer.

[0010] The present disclosure relates to cleaning compositions that can be used to clean semiconductor substrates. For example, these cleaning compositions can be used to remove defects caused by previous processing steps (such as CMP) on these semiconductor substrates. Specifically, these cleaning compositions can remove defects / contaminants from these semiconductor substrates, thereby making the substrate suitable for further processing. The cleaning compositions described herein generally contain an organic acid and an anionic polymer and have a pH value in the range of 0.1 to 7.

[0011] In one aspect, the disclosure features a cleaning composition comprising: at least one first organic acid; at least one second organic acid different from the at least one first organic acid, the at least one second organic acid comprising a diene acid; at least one anionic polymer selected from the group consisting of polyacrylic acid (PAA), poly(vinylphosphonic acid) (PVPA), poly(2-acrylamido-2-methyl-1-propanesulfonic acid), poly(N-vinylacetamide) (PNVA), anionic poly(methyl methacrylate) (PMMA), anionic polyacrylamide (PAM), polyaspartic acid (PASA), anionic poly(ethylene succinate) (PES ), anionic polybutylene succinate (PBS), polyvinyl alcohol (PVA), a copolymer of 2-acrylic acid and 2-methyl-2-((1-oxy-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium phosphite, a copolymer of 2-acrylic acid and 2-methyl-2-((1-oxy-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium bisulfite, a 2-acrylamide-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, a poly(4-styrenesulfonic acid-co-acrylic acid-co-vinylphosphonic acid) terpolymer and a mixture thereof; and water; wherein the pH value of the cleaning composition is about 0.1 to about 7.

[0012] In another aspect, the disclosure features a cleaning composition comprising: at least one first organic acid; at least one second organic acid different from the at least one first organic acid, the at least one second organic acid comprising 2,4-pentadienoic acid, 5-phenylpenta-2,4-dienoic acid, 2-hydroxypenta-2,4-dienoic acid, 2,4-hexadienoic acid, 4,5-hexadienoic acid, 4,6-heptadienoic acid, 2,6-dimethylheptadienoic acid, (3E,5E)-heptadienoic acid, (2E,5Z)-heptadienoic acid, octa-3,5-dienoic acid, (Z)-3,7-dimethyl-2,6-octa-2,5-dienoic acid, The cleaning composition comprises at least one anionic polymer; and water; wherein the cleaning composition has a pH of about 0.1 to about 7.

[0013] In another aspect, the disclosure features a method of cleaning a wafer surface, the method comprising contacting a wafer having a surface comprising SiN, SiC, TiN, W, Ru, Mo, TEOS, Cu, TaN, Co, or p-Si with a cleaning composition described herein.

[0014] In another aspect, the disclosure features a method of cleaning a substrate, the method comprising contacting the substrate with a cleaning composition described herein.

[0015] This Summary is provided to introduce concepts that will be further described in the Detailed Description below. This Summary is not intended to identify key features or essential characteristics of the claimed subject matter, nor is it intended as an aid in limiting the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Figure 2: Examples of various types of defects encountered before and after post-CMP cleaning using a post-CMP cleaner. The four defect modes shown in the figure (scratches, residual abrasive, and organic particles (droplets and dust)) mainly contribute to the total defect count (TDC) seen on the wafer. These defect images were collected on an Applied Materials SEMVision G5 SEM tool from Applied Materials.

[0017] Figure 2: Total defect counts (TDC) of silicon nitride wafers were collected on a KLA AIT XUV tool. Rows 1 and 2 show the TDC (also referred to as pre-images) of two wafers (i.e., wafer 1 and wafer 2) after CMP and before treatment with a P-CMP cleaning composition. Rows 3 and 4 show the TDC on these two wafers after treatment with a P-CMP cleaning composition (also referred to as post-images). The TDC number is shown next to each wafer. The comparative example (column 1) is the industry standard Fujifilm Wako P-CMP cleaner CLEAN-100. Columns 2, 3, and 4 describe the P-CMP cleaning compositions of the present disclosure, namely, cleaners A, B, and C. As can be seen from the wafer images, the comparative example only provides about 40% defect improvement, while the cleaners AC of the present invention provide about 90% to about 98% defect reduction.

[0018] Figure 3 : Total defect counts (TDC) on tungsten (W) and titanium nitride (TiN) wafers collected before CMP cleaning (PRE TDC) and after CMP cleaning with Cleaner C (PST TDC) on a KLA AIT XUV tool.

[0019] Figure 4 : Total defect counts (TDC) for various non-metal / silicon-based dielectric films collected on a KLA AIT XUV tool. Shown are TDCs before CMP cleaning (PRE TDC) and after CMP cleaning with Cleaner C (PST TDC). The films shown (from left to right) are i) TEOS (a form of silicon oxide), ii) LK (low-k dielectric), iii) ULK (ultra-low-k dielectric), iv) HARP (another form of silicon oxide), v) SiN (silicon nitride), and vi) SiC (silicon carbide).

[0020] Figure 5 : Total defect count (TDC) for patterned wafers containing various metal and non-metal films collected on a KLA AIT XUV tool. Shown is the TDC after CMP cleaning (PST TDC) with Cleaner C. For defects larger than 180nm, the PST-TDC for patterned wafers containing multiple die is approximately 150. DETAILED DESCRIPTION

[0021] Embodiments disclosed herein generally relate to cleaning compositions and methods of using such compositions to clean substrates (e.g., semiconductor substrates, such as wafers). In particular, the cleaning compositions can be used to clean substrates after CMP processes. However, the cleaning compositions described herein can also be used to remove residues and / or contaminants from substrate surfaces after etching processes, ashing processes, or electroplating processes.

[0022] As defined herein, residues and / or contaminants may include components present in a CMP polishing composition that has been used to polish a substrate to be cleaned (e.g., abrasives, molecular components, polymers, acids, bases, salts, surfactants, etc.), compounds generated during the CMP process due to chemical reactions between the substrate and the polishing composition and / or between components of the polishing composition, polymerized particles of the polishing pad, polishing by-products, organic or inorganic residues (from the CMP slurry or CMP pad), substrate (or wafer) particles released during the CMP process, and / or any other removable material known to be deposited on the substrate after a CMP process.

[0023] In one or more embodiments, the cleaning composition described herein includes: (1) at least one first organic acid; (2) at least one second organic acid different from the at least one first organic acid, the at least one second organic acid containing a diene acid; and (3) at least one anionic polymer. In one or more embodiments, the cleaning composition of the present disclosure may include: about 0.00001 wt % to about 50 wt % (e.g., about 0.01 wt % to about 5 wt %) of at least one first organic acid; about 0.0001 wt % to about 0.5 wt % (e.g., about 0.01 wt % to about 0.1 wt %) of at least one second organic acid; about 0.00001 wt % to about 50 wt % (e.g., about 0.005 wt % to about 10 wt %) of at least one anionic polymer; and the remainder (e.g., about 60 wt % to about 99.99 wt %) of a solvent (e.g., deionized water).

[0024] In one or more embodiments, the present disclosure provides a concentrated P-CMP cleaning composition that can be diluted with water to obtain a point-of-use (POU) cleaning composition up to 20 times, or up to 50 times, or up to 100 times, or up to 200 times, or up to 400 times, or up to 800 times, or up to 1000 times. In a preferred embodiment, the POU cleaning composition is diluted 200 times. In other embodiments, the present disclosure provides a point-of-use (POU) cleaning composition that can be used directly to clean a substrate surface.

[0025] In one or more embodiments, the POU cleaning composition may include: about 0.00001 wt % to about 5 wt % of at least one first organic acid (e.g., polycarboxylic acid); about 0.0001 wt % to about 0.1 wt % of at least one second organic acid (e.g., dienoic acid); and about 0.00001 wt % to about 5 wt % of at least one anionic polymer. In another embodiment, the POU cleaning composition may include: about 0.00001 wt % to about 5 wt % of at least one first organic acid (e.g., polycarboxylic acid); about 0.0001 wt % to about 0.1 wt % of at least one second organic acid (e.g., dienoic acid); about 0.00001 wt % to about 5 wt % of at least one third organic acid different from the first and second organic acids (e.g., amino acid); and about 0.00001 wt % to about 5 wt % of at least one anionic polymer.

[0026] In one or more embodiments, the concentrated P-CMP cleaning composition may include: about 0.01 wt % to about 30 wt % of at least one first organic acid (e.g., a polycarboxylic acid); about 0.01 wt % to about 0.5 wt % of at least one second organic acid (e.g., a dienoic acid); and about 0.005 wt % to about 15 wt % of at least one anionic polymer. In another embodiment, the concentrated P-CMP cleaning composition may include: about 0.01 wt % to about 30 wt % of at least one first organic acid (e.g., a polycarboxylic acid); about 0.01 wt % to about 0.5 wt % of at least one second organic acid (e.g., a dienoic acid); about 0.01 wt % to about 5 wt % of at least one third organic acid (e.g., an amino acid) different from the first and second organic acids; and about 0.005 wt % to about 15 wt % of at least one anionic polymer.

[0027] In one or more embodiments, the cleaning compositions described herein may include at least one (e.g., two, three, or four) organic acid. As used herein, the term "acid" includes an acid or a salt thereof (e.g., a potassium salt or sodium salt thereof). In some embodiments, at least one organic acid may be selected from the group consisting of carboxylic acids (e.g., monocarboxylic acids, polycarboxylic acids, and dienoic acids), amino acids, sulfonic acids, phosphoric acids, acrylic acids, and phosphonic acids or their salts. In some embodiments, at least one organic acid may be an acid or a salt thereof selected from formic acid, gluconic acid, acetic acid, malonic acid, citric acid, propionic acid, malic acid, adipic acid, succinic acid, lactic acid, oxalic acid, hydroxyethyl diphosphonic acid, 2-phosphono-1,2,4-butanetricarboxylic acid, aminotrimethylphosphonic acid, hexamethylenediaminetetrakis (methylenephosphonic acid), bis (hexamethylene) triaminephosphonic acid, aminoacetic acid, peracetic acid, potassium acetate, phenoxyacetic acid, glycine, diglycolic acid, glycerol Oleic acid, tri(hydroxymethyl)methylglycine (tricine), alanine, histidine, valine, phenylalanine, proline, glutamine, aspartic acid, ascorbic acid, glutamic acid, arginine, lysine, tyrosine, benzoic acid, 2,4-pentadienoic acid, 5-phenylpentadienoic acid, 2-hydroxypentadienoic acid, 2,4-hexadienoic acid (sorbic acid), 4,5-hexadienoic acid, 4,6-heptadienoic acid, 2,6-dienoic acid Methyl heptadienoic acid, (3E,5E)-heptadienoic acid, (2E,5Z)-heptadienoic acid, octadienoic acid, (Z)-3,7-dimethyl-2,6-octadienoic acid, 5,7-nonadienoic acid, (E,Z)-2,4-decadienoic acid, 2,5-decadienoic acid, undecadienoic acid, dodecadienoic acid, tridecadienoic acid, tetradecadienoic acid, pentadecadienoic acid, hexadecadienoic acid, The present invention relates to a group consisting of heptadecadienoic acid, (9Z,12E)-octadecadienoic acid, octadecadienoic acid, (10E,15Z)-9,12,13-trihydroxyoctadecadienoic acid, 13(S)-hydroxyoctadecadienoic acid, nonadecadienoic acid, heneicosadienoic acid, docosadienoic acid, eicosa-11,14-dienoic acid or mixtures thereof, salts thereof and mixtures thereof.

[0028] In one or more embodiments, at least one organic acid is included in the composition in an amount of about 0.00001% to about 50% by weight of the cleaning composition. For example, the at least one organic acid can be at least about 0.00001% by weight (e.g., at least about 0.00005% by weight, at least about 0.0001% by weight, at least about 0.0005% by weight, at least about 0.001% by weight, at least about 0.005% by weight, at least about 0.01% by weight, at least about 0.05% by weight, at least about 0.1% by weight, at least about 0.5% by weight, or at least about 1% by weight) to at most about 50% by weight (e.g., at most about 45% by weight, at most about 40% by weight, at most about 35% by weight, at most about 30% by weight, at most about 25% by weight, at most about 20% by weight, at most about 15% by weight, at most about 10% by weight, at most about 5% by weight, or at most about 1% by weight) of the cleaning composition described herein.

[0029] In one or more embodiments, the cleaning compositions described herein may include at least one first organic acid. In some embodiments, the at least one first organic acid may be selected from the group consisting of carboxylic acid (e.g., monocarboxylic acid and polycarboxylic acid (such as dicarboxylic acid and tricarboxylic acid)), sulfonic acid, phosphoric acid, acrylic acid, peracid and phosphonic acid. In some embodiments, the at least one first organic acid may be an acid selected from the group consisting of formic acid, gluconic acid, acetic acid, malonic acid, citric acid, propionic acid, malic acid, adipic acid, succinic acid, lactic acid, oxalic acid, hydroxyethyl diphosphonic acid, 2-phosphono-1,2,4-butanetricarboxylic acid, aminotrimethylphosphonic acid, hexamethylenediaminetetrakis (methylenephosphonic acid), bis (hexamethylene) triaminephosphonic acid, peracetic acid, phenoxyacetic acid, benzoic acid and mixtures thereof. In some embodiments, the at least one first organic acid may be a tricarboxylic acid (e.g., citric acid). In some embodiments, the at least one first organic acid does not include amino acids or dienoic acids.

[0030] In one or more embodiments, the at least one first organic acid can be at least about 0.00001 wt % (e.g., at least about 0.00005 wt %, at least about 0.0001 wt %, at least about 0.0005 wt %, at least about 0.001 wt %, at least about 0.005 wt %, at least about 0.01 wt %, at least about 0.05 wt %, at least about 0.1 wt %, at least about 0.5 wt %, or at least about 1 wt %) to at most about 50 wt % (e.g., at most about 45 wt %, at most about 40 wt %, at most about 35 wt %, at most about 30 wt %, at most about 25 wt %, at most about 20 wt %, at most about 15 wt %, at most about 10 wt %, at most about 8 wt %, at most about 6 wt %, at most about 5 wt %, at most about 4 wt %, at most about 2 wt %, or at most about 1 wt %) of the cleaning composition described herein.

[0031] In one or more embodiments, the cleaning compositions described herein may include at least one second organic acid different from at least one first organic acid. In some embodiments, the at least one second organic acid may be a dienoic acid (i.e., an acid containing a diene). In some embodiments, the dienoic acid may have 5 to 22 carbons (e.g., 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, or 22). In some embodiments, the dienoic acid may have 5 to 12 (e.g., 5, 6, 7, 8, 9, 10, 11, or 12) carbons. In some embodiments, the dienoic acid is a carboxylic acid containing a diene, such as 2,4-pentadienoic acid, 5-phenylpenta-2,4-dienoic acid, 2-hydroxypenta-2,4-dienoic acid, 2,4-hexadienoic acid (sorbic acid), 4,5-hexadienoic acid, 4,6-heptadienoic acid, 2,6-dimethylheptadienoic acid, (3E,5E)-heptadienoic acid, (2E,5Z)-heptadienoic acid, octa-3,5-dienoic acid, (Z)-3,7-dimethyl-2,6-octadienoic acid, 5,7-nonadienoic acid, (E,Z)-2,4-decadienoic acid , 2,5-decadienoic acid, undecadienoic acid, dodecadienoic acid, tridecadienoic acid, tetradecadienoic acid, pentadecadienoic acid, hexadecadienoic acid, heptadecadienoic acid, (9Z,12E)-octadecadienoic acid, octadecadienoic acid, (10E,15Z)-9,12,13-trihydroxyoctadecadienoic acid, 13(S)-hydroxyoctadecadienoic acid, 9Z,11E-9Z,12-13-dienoic acid, nonadecadienoic acid, heneicosadienoic acid, docosadienoic acid, eicosa-11,14-dienoic acid, or a mixture thereof.

[0032] In one or more embodiments, the at least one second organic acid can be at least about 0.0001 wt % (e.g., at least about 0.0005 wt %, at least about 0.001 wt %, at least about 0.005 wt %, at least about 0.01 wt %, at least about 0.02 wt %, at least about 0.04 wt %, or at least about 0.05 wt %) to at most about 0.5 wt % (e.g., at most about 0.4 wt %, at most about 0.3 wt %, at most about 0.2 wt %, at most about 0.1 wt %, at most about 0.08 wt %, at most about 0.06 wt %, at most about 0.05 wt %, at most about 0.04 wt %, at most about 0.03 wt %, at most about 0.02 wt %, at most about 0.01 wt %, or at most about 0.005 wt %) of the cleaning composition described herein.

[0033] Without wishing to be bound by theory, it is believed that including a second organic acid (e.g., a dienoic acid) within the above amount range can improve the corrosion inhibition of certain metals and metal-containing films (e.g., tungsten (W), copper (Cu), tantalum nitride (TaN), or titanium nitride (TiN)) on a substrate during a post-CMP cleaning process. As shown in the Examples below, electrochemical studies of some embodiments containing a dienoic acid (e.g., sorbic acid) show better corrosion protection of metals (e.g., W) compared to P-CMP compositions without a dienoic acid.

[0034] In one or more embodiments, the cleaning compositions described herein may include at least one third organic acid different from at least one first and second organic acids. In some embodiments, the at least one third organic acid may be an amino acid (e.g., a naturally occurring amino acid or a non-naturally occurring amino acid). In some embodiments, the at least one third organic acid may be selected from the group consisting of aminocarboxylic acids (e.g., glycine), glycine, bicine, tris(hydroxymethyl)methylglycine, alanine, histidine, valine, phenylalanine, proline, glutamine, aspartic acid, glutamic acid, arginine, lysine, tyrosine, and mixtures thereof.

[0035] In one or more embodiments, the at least one third organic acid can be at least about 0.001 wt % (e.g., at least about 0.005 wt %, at least about 0.01 wt %, at least about 0.05 wt %, at least about 0.1 wt %, at least about 0.5 wt %, or at least about 1 wt %) to at most about 20 wt % (e.g., at most about 18 wt %, at most about 16 wt %, at most about 15 wt %, at most about 14 wt %, at most about 12 wt %, at most about 10 wt %, at most about 8 wt %, at most about 6 wt %, at most about 5 wt %, at most about 4 wt %, at most about 2 wt %, at most about 1 wt %, or at most about 0.5 wt %) of the cleaning composition described herein.

[0036] In one or more embodiments, the cleaning compositions described herein include two organic acids, such as (1) citric acid and histidine or (2) citric acid and glycine. In some embodiments, the cleaning compositions include three organic acids, such as (1) citric acid, histidine and sorbic acid or (2) citric acid, histidine and glycine. In some embodiments, the cleaning compositions include four organic acids (e.g., citric acid, histidine, sorbic acid and glycine).

[0037] In one or more embodiments, the cleaning composition may include at least two or three organic acids (e.g., carboxylic acids, amino acids, and / or dienoic acids). In some embodiments, the amount of the first organic acid (e.g., carboxylic acids) is from about 0.0005% to about 10% by weight of the cleaning composition described herein. In some embodiments, the amount of the second organic acid (e.g., dienoic acid) is from about 0.0005% to about 0.5% by weight of the cleaning composition described herein. In some other embodiments, the amount of the third organic acid (e.g., amino acids) is from about 0.005% to about 5% by weight of the cleaning composition described herein.

[0038] In one or more embodiments, the cleaning composition described herein may include at least one (e.g., two or three) anionic polymers. In one or more embodiments, at least one anionic polymer may include one or more anionic groups, such as carboxylic acid, sulfate, and phosphate. In one or more embodiments, at least one anionic polymer is formed by one or more monomers selected from the group consisting of (meth) acrylic acid, maleic acid, acrylic acid, vinylphosphonic acid, vinyl phosphoric acid, vinyl sulfonic acid, allyl sulfonic acid, styrene sulfonic acid, acrylamide, acrylamidopropyl sulfonic acid, and sodium phosphonate. In more specific embodiments, at least one anionic polymer may be selected from poly (4-styrene sulfonic) acid (PSSA), polyacrylic acid (PAA), poly (vinylphosphonic acid) (PVPA), poly (2-acrylamido-2-methyl-1-propanesulfonic acid), poly (N-vinyl acetamide) (PNVA), polyethyleneimine (PEI), anionic poly (methyl methacrylate) (PMMA), anionic polyacrylamide (PAM), polyaspartic acid (PASA), anionic poly (vinyl succinate) (PES), anionic polysuccinic acid The present invention is a group consisting of butanediol ester (PBS), poly(vinyl alcohol) (PVA), copolymer of 2-acrylic acid and 2-methyl-2-((1-oxo-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium phosphite, copolymer of 2-acrylic acid and 2-methyl-2-((1-oxo-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium bisulfite, and 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, poly(4-styrenesulfonic acid-co-acrylic acid-co-vinylphosphonic acid) terpolymer, and mixtures thereof. Without wishing to be bound by theory, it is believed that the anionic polymer can dissolve hydrophobic polishing materials and / or defects on the wafer surface and facilitate their removal during post-CMP cleaning processes.

[0039] In one or more embodiments, the at least one anionic polymer may have a weight average molecular weight ranging from at least about 250 g / mol (e.g., at least about 500 g / mol, at least about 1000 g / mol, at least about 2,000 g / mol, at least about 5,000 g / mol, at least about 50,000 g / mol, at least about 100,000 g / mol, at least about 200,000 g / mol, or at least about 250,000 g / mol) to at most about 500,000 g / mol (e.g., at most about 400,000 g / mol, at most about 300,000 g / mol, at most about 200,000 g / mol, at most about 100,000 g / mol, or at most about 50,000 g / mol, or at most about 10,000 g / mol). In some embodiments, the weight average molecular weight of the at least one anionic polymer may be in the range of at least about 1000 g / mol to at most about 10,000 g / mol. In some embodiments, the weight average molecular weight of the at least one anionic polymer may be in the range of at least about 2000 g / mol to at most about 6,000 g / mol. In some embodiments, the at least one anionic polymer may have a weight average molecular weight of about 5,000 g / mol.

[0040] In some embodiments, the cleaning compositions described herein include an anionic polymer, such as poly(vinylphosphonic acid), 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, or poly(4-styrenesulfonic acid-co-acrylic acid-co-vinylphosphonic acid) terpolymer. In some embodiments, the cleaning compositions described herein include two anionic polymers, such as (1) poly(4-styrenesulfonic) acid and poly(acrylic) acid or (2) 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer and poly(acrylic) acid.

[0041] In one or more embodiments, at least one anionic polymer is included in the composition in an amount of about 0.00001% to about 50% by weight of the cleaning composition. For example, the at least one anionic polymer can be at least about 0.00001% by weight (e.g., at least about 0.00005%, at least about 0.0001%, at least about 0.0005%, at least about 0.001%, at least about 0.005%, at least about 0.01%, at least about 0.05%, at least about 0.1%, at least about 0.5%, or at least about 1%) to at most about 50% by weight (e.g., at most about 45%, at most about 40%, at most about 35%, at most about 30%, at most about 25%, at most about 20%, at most about 15%, at most about 10%, at most about 5%, or at most about 1%) of the cleaning composition described herein.

[0042] In some embodiments, the cleaning composition may include at least two or three anionic polymers. In some embodiments, the amount of the first anionic polymer is about 0.0005% to about 50% by weight of the cleaning composition described herein. In some embodiments, the amount of the second anionic polymer is about 0.0005% to about 30% by weight of the cleaning composition described herein. In some other embodiments, the amount of the third anionic polymer is about 0.0005% to about 10% by weight of the cleaning composition described herein.

[0043] In some embodiments, the pH of the cleaning composition can be in the range of at most about 7 (e.g., at most about 6.5, at most about 6, at most about 5.5, at most about 5, at most about 4.5, at most about 4, at most about 3.5, at most about 3, at most about 2.5, or at most about 2) to at least about 0.1 (e.g., at least about 0.2, at least about 0.5, at least about 1, at least about 2, at least about 2.5, at least about 3, or at least about 3.5). Without wishing to be bound by theory, it is believed that when the cleaning composition described herein has an acidic pH in the above range, it can provide sufficient protons to dissolve organic residues generated by CMP polishing of the substrate, and can provide sufficient cleaning action to dissolve inert metals (e.g., W, Cu) containing polishing byproducts.

[0044] Without wishing to be bound by theory, it is believed that the cleaning compositions described herein may include a single chemical material or all chemical materials in a much smaller concentration / amount than conventional cleaners (e.g., CLEAN-100) currently used in the semiconductor industry and still achieve better performance (e.g., better cleaning and / or reduced corrosion of exposed materials on the substrate). For example, the cleaning compositions described herein may include a chemical material or a total amount of chemical materials that is only about 5-20% by weight (e.g., about 5-15% by weight) of the same chemical material (e.g., an organic acid or anionic polymer) or the total amount of chemical materials in a conventional cleaner (e.g., CLEAN-100). Therefore, it is believed that the cleaning compositions described herein are more cost-effective and environmentally friendly than conventional cleaners (e.g., CLEAN-100) and provide a better overall cost of ownership when used on demand (because it is highly dilutable (e.g., up to 200 times)).

[0045] In one or more embodiments, the cleaning compositions described herein can be substantially free of one or more specific ingredients, such as organic solvents, pH adjusters, quaternary ammonium compounds (e.g., salts or hydroxides), alkaline bases (e.g., alkali metal hydroxides), fluorine-containing compounds, silanes (e.g., alkoxysilanes), nitrogen-containing compounds (e.g., amino acids, amines or imines, such as amidines, such as 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) and 1,5-diazabicyclo[4.3.0]non-5-ene (DBN)), polyols, salts (e.g., halides or metal salts), polymers (e.g., cationic, non-ionic or water-soluble polymers), inorganic acids (e.g., hydrochloric acid, sulfuric acid, phosphoric acid or nitric acid), surfactants (e.g., cationic surfactants, anionic surfactants, non-polymeric surfactants or non-ionic surfactants), plasticizers, oxidants (e.g., H2O2), corrosion inhibitors (e.g., azoles or non-azoles), The cleaning composition may be abrasive, e.g., abrasives, e.g., silica / cerium oxide abrasives, non-ionized abrasives, surface modified abrasives, or negatively / positively charged abrasives. Halide salts that may be excluded from the cleaning composition include alkali metal halides (e.g., sodium halides or potassium halides) or ammonium halides (e.g., ammonium chloride), and may be chlorides, bromides, or iodides. As used herein, a cleaning composition "substantially free of" an ingredient refers to an ingredient that is not intentionally added to the cleaning composition. In some embodiments, the cleaning composition described herein may have up to about 1000 ppm (e.g., up to about 500 ppm, up to about 250 ppm, up to about 100 ppm, up to about 50 ppm, up to about 10 ppm, or up to about 1 ppm) of the above ingredients that the cleaning composition is substantially free of. In some embodiments, the cleaning composition described herein may be completely free of one or more of the above ingredients.

[0046] In one or more embodiments, the cleaning compositions described herein may include a biocide. Exemplary biocides include, but are not limited to, isothiazolinones (e.g., benzisothiazolinone, methylisothiazolinone, and methylchloroisothiazolinone), 2-bromo-2-nitropropane-1,3-diol, hydrogen peroxide, and combinations thereof. In some embodiments, the amount of the biocide may be at most about 1000 ppm (e.g., at most about 500 ppm, at most about 250 ppm, at most about 100 ppm, at most about 50 ppm, or at most about 10 ppm) to at least about 1 ppm of the cleaning compositions described herein.

[0047] As applied to post-CMP cleaning operations, the cleaning compositions described herein can be effectively used to remove contaminants present on the surface of the substrate after the CMP processing step. In one or more embodiments, the contaminants causing defects may be at least one selected from the group consisting of abrasives, particles, organic residues, polishing byproducts, slurry byproducts, slurry-induced organic residues, inorganic polishing substrate residues, pad residues, and polyurethane residues. In one or more embodiments, the cleaning compositions of the present disclosure can be used to remove organic residues consisting of organic particles that are insoluble in water and therefore remain on the wafer surface after the CMP polishing step. In other embodiments, the cleaning compositions of the present disclosure can be used to remove abrasive residues / particles and / or polishing byproducts, and reduce scratches that cause defects on the wafer surface after the CMP polishing step.

[0048] Without wishing to be bound by theory, it is believed that the organic particles are generated by polishing composition components that are deposited on the substrate surface after polishing and are insoluble and therefore remain on the wafer surface as contaminants. The presence of these contaminants causes the number of defects on the wafer surface. When these defect counts are analyzed on a defect measurement tool (e.g., the AIT-XUV tool from KLA), a total defect count (TDC) is provided, which is the sum of all individual defect counts (see Figure 2 ). In one or more embodiments, the cleaning compositions described herein remove at least about 30% (e.g., at least about 50%, at least about 75%, at least about 80%, at least about 90%, at least about 95%, at least about 98%, at least about 99%, at least about 99.5%, or at least about 99.9%) to at most about 100% of the total number of defects (TDC) remaining on the substrate surface after polishing / CMP processing. The TDC removed from the wafer surface by the post-CMP cleaning composition is referred to as the cleaning efficacy of the cleaning composition and is expressed as a percentage. The higher the percentage, the better the cleaning effect, and the stronger the effectiveness / efficacy / effect of the cleaning composition.

[0049] Without wishing to be bound by theory, it is believed that there is an unexpected and unexpected synergistic effect of the components of the cleaning compositions described herein. For example, organic acids can reduce scratches and dissolve metal oxides and silica containing residues that can cause scratches (e.g., abrasive residues on wafers), amino acids can act as corrosion inhibitors for metals (e.g., tungsten), and anionic polymers are excellent solubilizers for hydrophobic organic residues remaining on the substrate surface after CMP processing. In addition, it is believed that the combination of tricarboxylic organic acids (e.g., citric acid) and dienoic acids (e.g., sorbic acid), optionally together with amino acids (e.g., histidine or glycine) and anionic polymers show a significant reduction in metal electrochemical corrosion, which is key to improving the yield of cleaned substrates after CMP processing.

[0050] In some embodiments, the present disclosure is characterized by a method for cleaning a substrate (e.g., a wafer). The method may include contacting a substrate with a cleaning composition described herein. In post-CMP cleaning applications, the cleaning composition may be applied to the substrate to be cleaned in any suitable manner. For example, the cleaning composition may be used with a variety of conventional cleaning tools and techniques (e.g., brush scrubbing, spin rinse drying, etc.). In one or more embodiments, after the CMP polishing step, the cleaning composition described herein may be used in an ultra-high frequency sonic cleaner module or in a brush box 1 or brush box 2 for an Applied Materials Reflexion 300mm CMP polishing tool of Applied Materials. The brush box has a brush for scrubbing action, and the cleaning composition provides a chemical action to remove defects. The cleaning composition may be applied to the surface of the wafer in the brush box or ultra-high frequency sonicator at a temperature in the range of 20°C to 60°C for a time in the range of about 5 seconds to about 10 minutes (e.g., about 15 seconds to 5 minutes).

[0051] In addition to brush boxes and / or UHF sonic cleaners, the cleaning compositions described herein can also be used in abrasive-free polishing chemistry for on-wafer plate polishing on a reflexion polisher to remove defects by polishing the wafer on a soft pad in the presence of the cleaning composition on the polishing pad. In other embodiments, the cleaning composition can be used in a polishing station to polish on a soft porous polymer pad in a polishing station module of an Applied Materials 4-platform Applied Materials Reflexion Prime 300mm CMP polishing tool.

[0052] In some embodiments, the substrate to be cleaned may include at least one material selected from the group consisting of low-k dielectrics (e.g., porous silicon oxide with k<3.5), ultra-low-k dielectrics (e.g., ultra-porous silicon oxide with k<2.5), tungsten, titanium nitride, tantalum nitride, silicon carbide, silicon oxide (e.g., TEOS), silicon nitride, copper, cobalt, molybdenum, ruthenium, and polysilicon on the wafer surface that may be exposed to the cleaning composition during the cleaning process.

[0053] In some embodiments, the method of using the cleaning composition described herein may further include producing a semiconductor device from a substrate treated with the cleaning composition via one or more steps. For example, photolithography, ion implantation, dry / wet etching, plasma etching, deposition (e.g., PVD, CVD, ALD, ECD), wafer mounting, die cutting, packaging, and testing may be used to produce a semiconductor device from a substrate treated with the cleaning composition described herein.

[0054] Although only a few examples are described in detail below, those skilled in the art will appreciate that many modifications may be made to the following exemplary embodiments without substantially departing from the present invention. Therefore, all such modifications should be included within the scope of the present disclosure defined in the claims.

[0055] Examples

[0056] Examples are provided to further illustrate the capabilities of the post-CMP cleaning compositions and methods of the present disclosure. The examples provided are not intended to and should not be considered to limit the scope of the present disclosure. Unless otherwise stated, any percentages listed are by weight (wt%). The anionic polymers described in the examples are obtained from different suppliers and, in some cases, may include slight differences in carbon chain length and molecular weight. The examples shown herein are representative and cannot cover the complete broad scope of the present disclosure.

[0057] Example 1: Demonstration of defect reduction and post-CMP cleaning effect of a post-CMP cleaning composition on silicon nitride wafers.

[0058] In this example, the control / comparative post-CMP cleaning composition is Fujifilm Wako CLEAN-100, which is an industry workhorse and has been used for over 10 years as the industry standard post-CMP cleaning composition for copper interconnect cleaning. WakoCLEAN-100 is generally known to include citric acid, a non-polymeric surfactant, and water. Four representative examples of post-CMP (P-CMP) cleaners from the present disclosure (i.e., Cleaners A, B, C, and D) were compared with Figure 2 The detergents were compared with CLEAN-100 shown in Table 1. Detergent A contained an anionic polymer (i.e., poly(vinylphosphonic acid) and two organic acids (i.e., citric acid and glycine). Detergent B contained two anionic polymers (i.e., poly(4-styrenesulfonic) acid and poly(acrylic) acid) and three organic acids (i.e., citric acid, sorbic acid and histidine). Detergent C contained an anionic polymer (i.e., 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer) and three organic acids (i.e., citric acid, sorbic acid and histidine). Detergent D contained an anionic polymer (i.e., poly(4-styrenesulfonic acid-co-acrylic acid-co-vinylphosphonic acid) terpolymer) and an organic acid (i.e., citric acid).

[0059] The comparative example CLEAN-100 was diluted 100 times to obtain a point-of-use (POU) cleaning composition, while the examples of the present disclosure, Cleaners A to D, were each diluted 200 times to obtain a point-of-use (POU) post-CMP (P-CMP) cleaning composition.

[0060] For post-CMP cleaning performance testing, feed defectivity (pre-cleaning TDC) was measured on SiN 12-inch wafers. Thereafter, an Applied Materials Reflexion polisher was used to polish 12-inch SiN wafers. The brush box of the polisher (containing PVA brushes) was immersed with a P-CMP cleaning composition (CLEAN-100 or Cleaners A to D; separate CMP polishing operations were performed on different SiN blanket wafers). After CMP polishing, the SiN wafer was moved through the brush box containing the P-CMP cleaning composition. After cleaning by a combination of chemical and mechanical action, the SiN wafer came out dry (dry in and dry out of the tool) and the post-cleaning defectivity (post-cleaning TDC) was measured by KLA on the AIT tool. The pre-cleaning TDC and post-cleaning TDC are summarized in Table 1 below and are shown in Table 1. Figure 2 Specifically, Figure 2 Wafer plots showing total defect count (TDC) on silicon nitride (SiN) wafers before and after cleaning with CLEAN-100 and cleaners A through C. Table 1 summarizes and quantifies the results for CLEAN-100 and cleaners A through D.

[0061] As can be seen from Table 1, the comparative example CLEAN-100 shows a cleaning efficacy of 40% on the SiN non-patterned film. In other words, after using CLEAN-100 as a post-CMP cleaning composition, the TDC on the SiN wafer is reduced by 40%. Typically, for a good post-CMP cleaning composition, the cleaning efficacy should be greater than 60%. Unexpectedly, the P-CMP cleaning composition disclosed herein is particularly effective in cleaning the surface of SiN wafers. As can be seen from Table 1, the cleaning efficiencies of cleaners A to D are 89%, 97%, 98% and 92%, respectively. The cleaning efficacy is calculated by the following formula: Cleaning efficacy = [(TDC before cleaning - TDC after cleaning) / TDC before cleaning] × 100%.

[0062] Table 1. Defectivity of SiN unpatterned wafers and total defect count (TDC) before and after cleaning

[0063]

[0064] Because Cleaner C was the most effective post-CMP cleaning composition, Cleaner C was further investigated in other examples on other films such as copper (Cu) and tantalum nitride (TaN) combinations (Example 2), tungsten (W) and titanium nitride (TiN) combinations (Example 3), and non-metals such as silicon oxide (TEOS and HARP), silicon nitride, and silicon carbide (Example 4). Cleaner C contains 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer (anionic polymer), citric acid (first organic acid), sorbic acid (second organic acid, dienoic acid), and histidine (third organic acid, amino acid). The anionic polymer is a copolymer of 2-acrylamido-2-methyl-1-propanesulfonic acid and acrylic acid, which is referred to herein as "2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer" and has a CAS number of 40623-75-4.

[0065] Example 5 describes the performance of Cleaner C on patterned wafers (containing multiple metal and non-metal films) during post-CMP cleaning. For Examples 2, 3, 4, and 5, Cleaner C was diluted 200 times to obtain a POU post-CMP cleaning composition.

[0066] Since Cu and W are two of the most important metals in semiconductor processing, not only the defectivity of the wafer map was studied, but also the electrochemical properties of Cleaner C for these metal combinations. The TDC and post-CMP cleaning efficacy of Cleaner C was also studied on non-metal / silicon-based dielectric films (see Example 4).

[0067] Example 2: Post-CMP cleaning performance and electrochemical characteristics of Cleaner C on a combination of Cu and TaN.

[0068] In this example, the defectivity performance / TDC reduction and electrochemical / galvanic corrosion characteristics of the composition of the present invention, Cleaner C, were studied on blank Cu and TaN wafers. Cu is typically found in back-end interconnect structures and is responsible for the wiring of transistors. Cu is found in multilayer metallization of TaN barriers that prevent electrons from migrating through the Cu lines and leaking out. Therefore, it is common practice to encapsulate the Cu metal in the TaN barrier metal nitride. Therefore, in this example, Cu and TaN wafers were studied.

[0069] The average TDC on Cu and TaN blank wafers before and after cleaning was measured on a KLA AIT XUV tool and the results are summarized in Table 2. As shown in Table 2, Cleaner C unexpectedly exhibited higher cleaning efficacy (ie, 89%) for TaN blank wafers.

[0070] Table 2. Cleaner C performance in reducing defectivity of Cu and TaN unpatterned wafers

[0071] Wafer film Average TDC before cleaning Average TDC after cleaning Cleaning effect Cu 864 762 12％ T N 1344 143 89％

[0072] The electrochemical properties of Cleaner C, Cleaner C without dienoic acid, and Comparative Example CLEAN-100 on Cu and TaN unpatterned wafers are summarized in Table 3. As can be seen from Table 3, Cleaner C exhibits a very low static etch rate (Static Etch Rate, SER) compared to Cleaner C and CLEAN-100 without dienoic acid (which do not include anionic polymers or amino acids or dienoic acids), i.e., 9.2 A / min on Cu film and 0.2 A / min on TaN film. In addition, Cleaner C exhibits a smaller electrochemical corrosion coupling current (ΔEcorr.), about 735 mV, compared to Cleaner C and CLEAN-100 without dienoic acid. These results indicate that Cleaner C significantly reduces the corrosion of Cu and TaN after post-CMP cleaning when compared to Cleaner C and CLEAN-100 without dienoic acid. In other words, post-CMP Cleaner C exhibits favorable electrochemical properties compared to Cleaner C and CLEAN-100 without dienoic acid. Without wishing to be bound by theory, it is believed that the synergistic effect of the amino acid (histidine) and dienoic acid (sorbic acid) in Cleaner C, which together act as dual corrosion inhibitors for Cu and TaN surface protection or passivation, Cleaner C provides lower SER and corrosion potential when compared to Cleaner C and CLEAN-100 without dienoic acid.

[0073] Table 3. Static Etch Rate (SER) and Electrochemical / Corrosion Properties of Back-End-of-Line (BEOL) Metals (such as Copper (Cu)) and Liners (such as Tantalum Nitride (TaN)) for the Inventive Formulation (Cleaner C) and Comparative Formulation (CLEAN-100)

[0074]

[0075] Icorr=corrosion current;Ecorr=corrosion voltage

[0076] Example 3: Post-CMP cleaning performance and electrochemical characteristics of Cleaner C on a combination of tungsten (W) and titanium nitride (TiN).

[0077] In this example, the composition of the present invention, Cleaner C, was studied for defectivity performance / TDC reduction and electrochemical / electrochemical corrosion characteristics of tungsten (W) and titanium nitride (TiN) unpatterned wafers. W is typically found in the front metal gate region and contacts, vias and plugs. After Cu, W is the most common metal in semiconductors. W is typically found with a TiN barrier layer that prevents electrons from migrating through the W metal gate, plug, contact or wire and leaking. Therefore, W metal is typically encapsulated in a TiN barrier metal nitride. Therefore, W and TiN were studied in this example.

[0078] Table 4. Cleaner C performance in reducing defectivity of W and TiN blank wafers

[0079] Wafer film Average TDC before cleaning Average TDC after cleaning Cleaning effect W 365 24 93％ TiN 22833 10875 52％

[0080] The average TDC on the W and TiN blank wafers before and after cleaning is summarized in Table 4 and shown in Table 4. Figure 3 As shown in Table 4, Cleaner C is surprisingly effective in cleaning W wafers due to its high 93% post-CMP cleaning efficacy for W films.

[0081] The electrochemical properties of Cleaner C, Cleaner C without diene acid (sorbic acid), and Comparative Example CLEAN-100 on W and TiN unpatterned wafers are summarized in Table 5. Also included in Table 5 are two compositions, Cleaners E and F, which are the same as Cleaner C, but the histidine used in Cleaner C is replaced by an equal amount of glycine and aspartic acid, respectively. As can be seen from Table 5, among the cleaning compositions tested, Cleaner C exhibits a relatively low static etch rate (SER), i.e., 1.48 A / min on W film and 0.068 A / min on TiN film. In addition, Cleaner C exhibited a minimum electrochemical corrosion coupling current voltage (ΔEcorr.) of about 119 mV and a lower SER compared to CLEAN-100 (which does not include anionic polymers or amino acids or dienoic acid) or Cleaner C without dienoic acid, indicating that the corrosion of W and TiN after post-CMP cleaning with Cleaner C was substantially less than that of CLEAN-100 or Cleaner C without dienoic acid. Without being bound by theory, it is believed that the synergistic combination of the first organic acid (carboxylic acid), the second organic acid (dienoic acid), and the third organic acid (amino acid) as present in Cleaner C can significantly reduce the SER and improve the metal corrosion inhibition ability. In summary, compared to CLEAN-100, Post-CMP Cleaner C (which contains dienoic acid) exhibits the most favorable electrochemical characteristics because Cleaner C has lower electrochemical corrosion and lower SER.

[0082] Table 5. Static Etch Rate (SER) and Electrochemical / Corrosion Properties of FEOL Metals (such as Tungsten (W)) and Liners (such as Titanium Nitride (TiN)) for Inventive Formulations and Comparative Formulations (CLEAN-100)

[0083] Example 4: Post-CMP cleaning performance of Cleaner C on non-metal / silicon based dielectrics.

[0084] On a typical patterned wafer / device wafer, there are metals such as Cu and W and non-metals / insulators such as silicon oxide, nitride and carbide. The metal / wire conducts electricity / electrons and the non-metal / insulator prevents electron leakage by encapsulating the metal. The most important metals are generally Cu and W, while the most important insulators / dielectrics are generally silicon oxide and silicon nitride. Therefore, the cleaning composition will need to have effective cleaning performance on these insulators / non-metals because they are mixed with the metals on any semiconductor chip.

[0085] In this example, the composition of the present invention, Cleaner C, was studied on various non-metals that are commonly silicon-based dielectric films. Specifically, the silicon-based dielectric films studied were: i) TEOS (a form of silicon oxide), ii) LK (low-k dielectric; e.g., porous silicon oxide with k<3.5), iii) ULK (ultra-low-k dielectric; e.g., ultra-porous silicon oxide with k<2.5), iv) HARP (another form of silicon oxide), v) SiN (silicon nitride), and vi) SiC (silicon carbide). The average TDC on the dielectric blank wafer before and after cleaning and the cleaning efficacy of Cleaner C on these six films are summarized in Table 6.

[0086] As insulators for Cu and W conductors of semiconductor devices, the main silicon-based dielectrics are silicon oxides (TEOS and HARP) and silicon nitride (SiN). As can be seen from Table 6, Cleaner C unexpectedly exhibits significant cleaning efficacy on both silicon oxides (99% for TEOS and 99.8% for HARP) and silicon nitride (91%).

[0087] Table 6. Defect reduction performance of Cleaner C on non-metal / silicon based unpatterned wafers

[0088] Wafer film Average TDC before cleaning Average TDC after cleaning Cleaning effect TEOS 10320 144 99％ LK 8156 3491 57％ ULK 3651 644 82％ HARP 35015 79 99.8％ S N 17528 1631 91％ SiC 1031 797 23％

[0089] Example 5: Post-CMP cleaning performance of Cleaner C on patterned device wafers.

[0090] Examples 1-4 have shown the performance of Cleaner C on unpatterned films containing only one material exposed to the post-CMP cleaning composition. However, actual chips / devices typically contain many metal and non-metal film types on a single chip. These multi-layer film wafers are called patterned wafers, and after all fabrication / processing has been performed on the patterned wafers, these wafers are cut into dies / individual chips.

[0091] In Example 5, the performance of Cleaner C was tested on patterned wafers that had been polished by a CMP process. After cleaning with Cleaner C, the total defect count (TDC) was analyzed on a KLA AIT-XUV defectivity measurement tool. Figure 5 , shows a TDC plot of a patterned wafer after cleaning with Cleaner C diluted 200X as-needed (POU). Figure 5 It can be seen that the patterned wafer is very clean and has very low defectivity. For defects larger than 180 nm in size, the TDC of the patterned wafer is as low as about 150. This further demonstrates the high defectivity cleaning efficacy of the cleaning composition of the present disclosure on patterned / device wafers.

[0092] Although the present disclosure has been described with respect to the examples set forth herein, it should be understood that other modifications and variations are possible without departing from the spirit and scope of the present disclosure as defined in the following claims.

Claims

1. A cleaning composition comprising: at least one first organic acid; at least one second organic acid different from the at least one first organic acid, the at least one second organic acid comprising a dienoic acid; at least one anionic polymer selected from the group consisting of polyacrylic acid (PAA), poly(vinylphosphonic acid) (PVPA), poly(2-acrylamido-2-methyl-1-propanesulfonic acid), poly(N-vinylacetamide) (PNVA), anionic poly(methyl methacrylate) (PMMA), anionic polyacrylamide (PAM), polyaspartic acid (PASA), anionic poly(vinyl succinate) (PES), anionic polybutylene succinate (PBS), polyvinyl alcohol (PVA), copolymer of 2-acrylic acid and 2-methyl-2-((1-oxo-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium phosphite, copolymer of 2-acrylic acid and 2-methyl-2-((1-oxo-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium bisulfite, 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, poly(4-styrenesulfonic acid-co-acrylic acid-co-vinylphosphonic acid) terpolymer, and mixtures thereof; and water; The pH value of the cleaning composition is about 0.1 to about 7.

2. The cleaning composition according to claim 1, wherein The at least one first organic acid comprises a monocarboxylic acid or a polycarboxylic acid.

3. The cleaning composition according to claim 1, wherein The at least one first organic acid is selected from the group consisting of formic acid, acetic acid, malonic acid, citric acid, propionic acid, malic acid, adipic acid, succinic acid, aspartic acid, ascorbic acid, lactic acid, oxalic acid, hydroxyethyldiphosphonic acid, 2-phosphono-1,2,4-butanetricarboxylic acid, aminotrimethylenephosphonic acid, hexamethylenediaminetetrakis(methylenephosphonic acid), bis(hexamethylene)triaminephosphonic acid, peracetic acid, potassium acetate, phenoxyacetic acid, benzoic acid, and mixtures thereof.

4. The cleaning composition according to claim 1, wherein The at least one first organic acid is selected from the group consisting of acetic acid, malonic acid, citric acid, propionic acid, malic acid, succinic acid, ascorbic acid, lactic acid, oxalic acid, and mixtures thereof.

5. The cleaning composition according to claim 1, wherein The at least one first organic acid is present in an amount from about 0.00001 wt % to about 50 wt % of the cleaning composition.

6. The cleaning composition according to claim 1, wherein The at least one second organic acid comprises a dienoic acid having 5 to 22 carbons.

7. The cleaning composition according to claim 6, wherein The at least one second organic acid comprises 2,4-pentadienoic acid, 5-phenylpenta-2,4-dienoic acid, 2-hydroxypenta-2,4-dienoic acid, 2,4-hexadienoic acid, 4,5-hexadienoic acid, 4,6-heptadienoic acid, 2,6-dimethylheptadienoic acid, (3E,5E)-heptadienoic acid, (2E,5Z)-heptadienoic acid, octa-3,5-dienoic acid, (Z)-3,7-dimethyl-2,6-octadienoic acid, 5,7-nonadienoic acid, (E,Z)-2,4-decadienoic acid, 2,5- Decadienoic acid, undecadienoic acid, dodecadienoic acid, tridecadienoic acid, tetradecadienoic acid, pentadecadienoic acid, hexadecadienoic acid, heptadecadienoic acid, (9Z, 12E)-octadecadienoic acid, octadecadienoic acid, (10E, 15Z)-9,12,13-trihydroxyoctadecadienoic acid, 13(S)-hydroxyoctadecadienoic acid, nonadecadienoic acid, heneicosadienoic acid, docosadienoic acid, eicosa-11,14-dienoic acid or a mixture thereof.

8. The cleaning composition according to claim 1, wherein The at least one second organic acid is present in an amount from about 0.0001 wt. % to about 0.5 wt. % of the cleaning composition.

9. The cleaning composition according to claim 1, wherein Further included is at least one third organic acid different from the at least one first organic acid and the at least one second organic acid, the at least one third organic acid comprising an amino acid.

10. The cleaning composition according to claim 9, wherein The at least one third organic acid comprises aminocarboxylic acid, glycine, N,N-bicine, tris(hydroxymethyl)methylglycine, alanine, histidine, valine, phenylalanine, proline, glutamine, aspartic acid, glutamic acid, arginine, lysine, tyrosine or a mixture thereof.

11. The cleaning composition according to claim 9, wherein The at least one third organic acid comprises glycine, histidine, alanine, proline, arginine, lysine, aspartic acid, or a mixture thereof.

12. The cleaning composition according to claim 9, wherein The at least one third organic acid is present in an amount from about 0.001 wt % to about 20 wt % of the cleaning composition.

13. The cleaning composition according to claim 1, wherein The at least one anionic polymer includes polyacrylic acid (PAA), poly(vinylphosphonic acid) (PVPA), poly(2-acrylamido-2-methyl-1-propanesulfonic acid), poly(N-vinylacetamide) (PNVA), anionic poly(methyl methacrylate) (PMMA), anionic polyacrylamide (PAM), 2-acrylamido-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, poly(4-styrenesulfonic acid-co-acrylic acid-co-vinylphosphonic acid) terpolymer or a mixture thereof.

14. The cleaning composition according to claim 1, wherein The at least one anionic polymer is present in an amount of from about 0.00001% to about 50% by weight of the cleaning composition.

15. The cleaning composition according to claim 1, wherein The pH of the cleaning composition is from about 1 to about 6.

5.

16. The cleaning composition according to claim 1, wherein The cleaning composition has a pH of from about 2 to about 5.

17. A cleaning composition comprising: at least one first organic acid; At least one second organic acid different from the at least one first organic acid comprises 2,4-pentadienoic acid, 5-phenylpenta-2,4-dienoic acid, 2-hydroxypenta-2,4-dienoic acid, 2,4-hexadienoic acid, 4,5-hexadienoic acid, 4,6-heptadienoic acid, 2,6-dimethylheptadienoic acid, (3E,5E)-heptadienoic acid, (2E,5Z)-heptadienoic acid, octa-3,5-dienoic acid, (Z)-3,7-dimethyl-2,6-octadienoic acid, acid, 5,7-nonadienoic acid, (E,Z)-2,4-decadienoic acid, 2,5-decadienoic acid, undecadienoic acid, dodecadienoic acid, tridecadienoic acid, tetradecadienoic acid, pentadecadienoic acid, hexadecadienoic acid, heptadecadienoic acid, (10E,15Z)-9,12,13-trihydroxyoctadecadienoic acid, 13(S)-hydroxyoctadecadienoic acid, 9Z,11E-dienoic acid, nonadecadienoic acid, heneicosadienoic acid, docosadienoic acid, eicosa-11,14-dienoic acid or a mixture thereof; at least one anionic polymer; and water; The pH value of the cleaning composition is about 0.1 to about 7.

18. The cleaning composition according to claim 17, wherein The at least one anionic polymer is selected from the group consisting of poly(4-styrenesulfonic acid) (PSSA), polyacrylic acid (PAA), poly(vinylphosphonic acid) (PVPA), poly(2-acrylamido-2-methyl-1-propanesulfonic acid), poly(N-vinylacetamide) (PNVA), anionic poly(methyl methacrylate) (PMMA), anionic polyacrylamide (PAM), polyaspartic acid (PASA), anionic poly(ethylene succinate) (PES), anionic polybutylene succinate (PBS) , polyvinyl alcohol (PVA), copolymer of 2-acrylic acid and 2-methyl-2-((1-oxy-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium phosphite, copolymer of 2-acrylic acid and 2-methyl-2-((1-oxy-2-propenyl)amino)-1-propanesulfonic acid monosodium salt and sodium bisulfite, 2-acrylamide-2-methyl-1-propanesulfonic acid-acrylic acid copolymer, poly(4-styrenesulfonic acid-co-acrylic acid-co-vinylphosphonic acid) terpolymer and mixtures thereof.

19. A method for cleaning a wafer surface, comprising: A wafer having a surface comprising SiN, SiC, TiN, W, Ru, Mo, TEOS, Cu, TaN, Co, or p-Si is contacted with the cleaning composition of claim 1.

20. A method for cleaning a substrate, comprising: A substrate is contacted with the cleaning composition of claim 1.

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