Cleaning preparations

Abstract

The present disclosure relates to a cleaning composition comprising: 1) at least one redox agent; 2) at least one organic solvent selected from the group consisting of water-soluble alcohols, water-soluble ketones, water-soluble esters, water-soluble sulfones, and water-soluble ethers; 3) at least one boron-containing compound selected from the group consisting of boric acid, boronic acids, and salts thereof; and 4) water.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 62 / 457,293, filed February 10, 2017, which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to novel cleaning compositions for semiconductor substrates and methods for cleaning semiconductor substrates. Specifically, the present disclosure relates to cleaning compositions for removing residues remaining on a semiconductor substrate after a metal layer or a dielectric material layer disposed on the substrate has been plasma etched and the entire resist has been removed by a plasma ashing process. [Background technology]

[0003] In the fabrication of integrated circuit devices, photoresist is used as an intermediate mask to transfer the original mask pattern of a reticle to a wafer substrate through a series of photolithography and plasma etching steps. One of the essential steps in the fabrication process of integrated circuit devices is the removal of the patterned photoresist film from the wafer substrate. This step is generally accomplished by one of two methods:

[0004] One method involves a wet stripping step in which a photoresist-coated substrate is contacted with a photoresist stripper solution consisting primarily of an organic solvent and an amine. However, such stripper solutions generally cannot completely and reliably remove the photoresist film, especially if the photoresist film has been subjected to UV radiation and plasma treatment during the manufacturing process. Some photoresist films become highly crosslinked by such treatments, making them more difficult to dissolve in the stripper solution. In addition, the chemicals used in these conventional wet stripping methods can be ineffective at removing inorganic or organometallic residues formed during plasma etching of metal or oxide layers using halogen-containing gases.

[0005] Another method for removing photoresist films involves exposing the photoresist-coated substrate to an oxygen-based plasma to burn the resist film from the substrate in a process known as plasma ashing. However, plasma ashing is also not fully effective at removing the plasma etching by-products mentioned above. Removal of these plasma etching by-products is typically achieved by exposing the treated metal and dielectric thin films to cleaning solutions.

[0006] Metal-containing substrates are generally susceptible to corrosion. For example, substrates such as aluminum, copper, aluminum-copper alloys, tungsten nitride, tungsten (W), cobalt (Co), titanium oxide, other metals, and metal nitrides are susceptible to corrosion. Furthermore, conventional cleaning chemistries can etch dielectrics (e.g., interlayer dielectrics or ultra low-k dielectrics) in integrated circuit devices. Furthermore, the amount of corrosion tolerated by integrated circuit device manufacturers is becoming less and less as devices shrink.

[0007] Additionally, as residue removal becomes more difficult and corrosion levels must be kept ever lower, cleaning solutions should be safe to use and environmentally friendly. Summary of the Invention [Problem to be solved by the invention]

[0008] Therefore, the cleaning solution should be effective in removing plasma etching and ashing residues and not corrode any exposed substrate material. [Means for solving the problem]

[0009] The present disclosure relates to non-corrosive cleaning compositions useful for removing residues (e.g., plasma etching and / or plasma ashing residues) from semiconductor substrates as an intermediate step in a multi-step manufacturing process. These residues include various relatively insoluble mixtures of: organic compounds such as residual photoresist; organometallic compounds; metal oxides such as aluminum oxide (AlOx), titanium oxide (TiOx), zirconium oxide (ZrOx), tantalum oxide (TaOx), and hafnium oxide (HfOx) (which may form as reaction by-products from exposed metals); metals such as aluminum (Al), aluminum / copper alloys, copper (Cu), titanium (Ti), tantalum (Ta), tungsten (W), and cobalt (Co); metal nitrides such as aluminum nitride (AlN), aluminum oxynitride (AlOxNy), titanium nitride (TiN), tantalum nitride (TaN), and tungsten nitride (WN); alloys thereof; and other materials. An advantage of the cleaning compositions described herein is that they can clean a variety of residues generated and are generally non-corrosive to exposed substrate materials (e.g., exposed metals such as aluminum, aluminum / copper alloys, copper, titanium, tantalum, tungsten, and cobalt), metal nitrides such as titanium nitride, tantalum nitride, and tungsten nitride, and alloys thereof).

[0010] The present disclosure provides, in one aspect, 1) at least one redox agent; 2) at least one organic solvent selected from the group consisting of water-soluble alcohols, water-soluble ketones, water-soluble esters, water-soluble sulfones, and water-soluble ethers; 3) at least one boron-containing compound selected from the group consisting of boric acid, boronic acids, and salts thereof; 4) Water and The present invention relates to a cleaning composition comprising:

[0011] The present disclosure also relates to a method for cleaning residue from a semiconductor substrate, the method comprising contacting a semiconductor substrate containing post-etch and / or post-ash residue with a cleaning composition described herein. The method may, for example, comprise: (A) providing a semiconductor substrate containing post-etch residue and / or post-ash residue; (B) contacting the semiconductor substrate with a cleaning composition described herein; (C) rinsing the semiconductor substrate with a suitable rinsing solvent; and (D) optionally, drying the semiconductor substrate by any means that removes the rinse solvent and does not impair the quality of the semiconductor substrate; may also include: DETAILED DESCRIPTION OF THE INVENTION

[0012] In this specification, unless otherwise specified, all percentages listed should be understood to be weight percentages based on the total weight of the cleaning composition. Unless otherwise specified, ambient temperature is defined as about 16 degrees Celsius (°C) to about 27 degrees Celsius (°C) (e.g., 25°C).

[0013] The terms "layer" and "film" are interchangeable.

[0014] As used herein, a "water-soluble" substance (e.g., a water-soluble alcohol, a water-soluble ketone, a water-soluble ester, a water-soluble sulfone, or a water-soluble ether) means a substance that has a solubility in water at 25°C of 5% by weight or more.

[0015] Certain embodiments of the present disclosure include: 1) at least one redox agent; 2) at least one organic solvent selected from the group consisting of water-soluble alcohols, water-soluble ketones, water-soluble esters, water-soluble sulfones, and water-soluble ethers; 3) at least one boron-containing compound selected from the group consisting of boric acid, boronic acids, and salts thereof; 4) Water and The present invention relates to a non-corrosive cleaning composition comprising:

[0016] Generally, the cleaning compositions of the present disclosure contain at least one redox agent, which is believed to aid in dissolving residues, such as photoresist residues, metal residues, and metal oxide residues, on semiconductor surfaces. As used herein, the term "redox agent" refers to a compound capable of causing oxidation and / or reduction in semiconductor cleaning processes. Suitable redox agents include hydroxylamines. In some embodiments, the redox agents or cleaning compositions described herein do not contain peroxides (e.g., hydrogen peroxide).

[0017] In certain embodiments, the compositions of the present disclosure comprise about 0.5% by weight or more (e.g., about 1% by weight or more, about 2% by weight or more, about 3% by weight or more, or about 5% by weight or more) and / or about 20% by weight or less (e.g., about 17% by weight or less, about 15% by weight or less, about 12% by weight or less, or about 10% by weight or less) of redox agent.

[0018] The composition of the present disclosure contains at least one (e.g., two, three, four, or more) organic solvent selected from the group consisting of water-soluble alcohols, water-soluble ketones, water-soluble esters, water-soluble sulfones, and water-soluble ethers (e.g., glycol diethers).

[0019] Water-soluble alcohols include, but are not limited to, alkanediols (including, but not limited to, alkylene glycols), glycols, alkoxy alcohols (including, but not limited to, glycol monoethers), saturated aliphatic monohydric alcohols, unsaturated non-aromatic monohydric alcohols, and low molecular weight alcohols having a ring structure (e.g., those having a molecular weight of less than 500 g / mol, less than 400 g / mol, less than 300 g / mol, less than 200 g / mol, or less than 100 g / mol).

[0020] Water-soluble alkanediols include, but are not limited to, 2-methyl-1,3-propanediol, 1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 2,3-butanediol, pinacol, and alkylene glycols.

[0021] Water-soluble alkylene glycols include, but are not limited to, ethylene glycol, propylene glycol, hexylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, and tetraethylene glycol.

[0022] Water-soluble alkoxy alcohols include, but are not limited to, 3-methoxy-3-methyl-1-butanol, 3-methoxy-1-butanol, 1-methoxy-2-butanol, and water-soluble alkylene glycol monoethers.

[0023] Examples of water-soluble alkylene glycol monoethers include, but are not limited to, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, 1-methoxy-2-propanol, 2-methoxy-1-propanol, 1-ethoxy-2-propanol, 2-ethoxy-1-propanol, propylene glycol mono-n-propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monobenzyl ether, and diethylene glycol monobenzyl ether.

[0024] Water-soluble saturated aliphatic monohydric alcohols include, but are not limited to, methanol, ethanol, n-propyl alcohol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 2-pentanol, t-pentyl alcohol, and 1-hexanol.

[0025] Water-soluble unsaturated non-aromatic monohydric alcohols include, but are not limited to, allyl alcohol, propargyl alcohol, 2-butenyl alcohol, 3-butenyl alcohol, and 4-penten-2-ol.

[0026] Water-soluble low molecular weight alcohols having a ring structure include, but are not limited to, tetrahydrofurfuryl alcohol, furfuryl alcohol, and 1,3-cyclopentanediol.

[0027] Water-soluble ketones include, but are not limited to, acetone, propanone, cyclobutanone, cyclopentanone, cyclohexanone, diacetone alcohol, 2-butanone, 2,5-hexanedione, 1,4-cyclohexanedione, 3-hydroxyacetophenone, 1,3-cyclohexanedione, and cyclohexanone.

[0028] Water-soluble esters include, but are not limited to, ethyl acetate; glycol monoesters such as ethylene glycol monoacetate, diethylene glycol monoacetate; and glycol monoether monoesters such as propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, and ethylene glycol monoethyl ether acetate.

[0029] Water soluble sulfones include, but are not limited to, sulfolane, dimethyl sulfone, 1,3-propane sulfone, 1,4-butane sulfone, busulfan, sulfolene, ethyl methyl sulfone, diphenyl sulfone, and methyl phenyl sulfone.

[0030] Water-soluble ethers include, but are not limited to, the alkoxy alcohols (for example, alkylene glycol monoethers) described above.

[0031] In some embodiments, the cleaning compositions of the present disclosure comprise about 60% by weight or more (e.g., about 65% by weight or more, about 70% by weight or more, or about 75% by weight or more) and / or about 95% by weight or less (e.g., about 90% by weight or less, about 85% by weight or less, or about 80% by weight or less) of at least one organic solvent.

[0032] The cleaning compositions of the present disclosure further comprise water. The water is preferably deionized, ultrapure, and free of organic contaminants, and has a minimum resistivity of about 4 to about 17 megaohms. More preferably, the resistivity of the water is 17 megaohms or greater.

[0033] In some embodiments, cleaning compositions of the present disclosure comprise about 5% by weight or more (e.g., about 8% by weight or more, about 12% by weight or more, or about 16% by weight or more) and / or about 28% by weight or less (e.g., about 24% by weight or less, about 20% by weight or less, or about 18% by weight or less) water.

[0034] In some embodiments, the cleaning compositions of the present disclosure include at least one boron-containing compound, which may be selected from the group consisting of boric acid (HBO), boronic acids, and salts thereof. In certain embodiments, the boron-containing compound has Formula (I): RB-(OH)2(I) wherein R is C1-C 10 It is alkyl (eg, C1-C4 alkyl) or aryl (eg, phenyl). The boronic acid of formula (I) can include phenylboronic acid. In some embodiments, the salts of boric acid or boronic acids can be metal salts, ammonium salts, or tetraalkylammonium salts. Metal salts can be formed from alkali metals (e.g., Li, Na, K, Rb, or Cs) or alkaline earth metals (e.g., Mg, Ca, Sr, or Ba). Tetraalkylammonium salts can include tetramethylammonium cations, tetraethylammonium cations, tetrapropylammonium cations, and tetrabutylammonium cations.

[0035] In some embodiments, the cleaning compositions of the present disclosure comprise about 0.001 wt. % or more (e.g., about 0.002 wt. % or more, about 0.005 wt. % or more, about 0.01 wt. % or more, about 0.015 wt. % or more, about 0.02 wt. % or more, about 0.05 wt. % or more, or about 0.1 wt. % or more) and / or about 0.2 wt. % or less (e.g., about 0.18 wt. % or less, about 0.15 wt. % or less, about 0.12 wt. % or less, about 0.1 wt. % or less, or about 0.05 wt. % or less) of at least one boron-containing compound. Without being bound by theory, it is believed that including the boron-containing compound in the cleaning composition in the amounts described above allows for a reduction in the corrosive effect of the composition on exposed substrate material (e.g., cobalt) that is not intended to be removed during the cleaning process (e.g., by reducing the etch rate of the cleaning composition on the exposed substrate material).

[0036] The cleaning compositions of the present disclosure may optionally include at least one additive, such as a metal-containing additive and a cleaning additive.

[0037] Metal-containing additives contemplated for use in the cleaning compositions of the present disclosure include metals selected from Group 2A metals, Group 3B metals, Group 4B metals, Group 5B metals, and lanthanide metals. In some embodiments, the metal is Ca, Ba, Ti, Hf, Sr, La, Ce, W, V, Nb, or Ta. In some embodiments, the metal is selected from Group 4B metals (such as Ti or Hf).

[0038] The metal-containing additive may be a metal halide, a metal hydroxide, a metal boride, a metal alkoxide, a metal oxide, or a metal-containing ammonium salt. In some embodiments, the metal-containing additive is an ammonium salt. The ammonium salt may be a salt represented by the following formula (I): (NH4) m MX n Formula (I) In formula (I), m is 1, 2, 3, or 4; n is 1, 2, 3, 4, 5, or 6; M is a metal ion (such as a Group 2A metal, Group 3B metal, Group 4B metal, Group 5B metal, or lanthanide metal ion); and X is a halide ion (e.g., F, Cl, Br, or I). In some embodiments, the metal-containing additive is ammonium hexafluorotitanate ((NH4)2TiF6), and metal-containing additives include tungsten boride, Ca(OH)2, BaCl2, SrCl2, LaCl3, CeCl3, (NH4)2TiF6, BaTiO3, Ti(OEt)4, Ti(OCH(CH3)2)4, HfO2, VO5, Nb2O5, or TaF3.

[0039] In some embodiments, the metal-containing additive may be present in an amount of about 0.001 wt. % or more (e.g., about 0.002 wt. % or more, about 0.004 wt. % or more, about 0.006 wt. % or more, about 0.008 wt. % or more, or about 0.01 wt. % or more) and / or about 0.5 wt. % or less (e.g., about 0.4 wt. % or less, about 0.3 wt. % or less, about 0.2 wt. % or less, about 0.1 wt. % or less, about 0.08 wt. % or less, about 0.06 wt. % or less, about 0.04 wt. % or less, about 0.02 wt. % or less, or about 0.01 wt. % or less) of the composition. Without being bound by theory, it is believed that the inclusion of the metal-containing additive in the cleaning composition in the above amounts reduces the corrosive effect of the composition, i.e., reduces the etch rate of the cleaning composition against exposed substrate materials (e.g., exposed metal or dielectric materials) that are not intended to be removed during the cleaning process.

[0040] In some embodiments, the cleaning compositions of the present disclosure may optionally contain at least one cleaning additive to improve their detergency (e.g., removal of etching or ashing residues) and / or reduce their corrosive effects. In some embodiments, the cleaning additive may be a sulfur-containing additive or an amino acid. In some embodiments, the cleaning composition may include both a sulfur-containing additive and an amino acid.

[0041] The sulfur-containing additives contemplated for use in the cleaning compositions of the present disclosure are not particularly limited. In some embodiments, the sulfur-containing additives include a thiol moiety (i.e., SH) or a thioether moiety (e.g., SR, where R is C-C 10 In some embodiments, the sulfur-containing additive may be an alcohol, an acid, an amine, or a heterocyclic compound having a thiol or thioether moiety. Examples of sulfur-containing additives include, but are not limited to, 3-amino-5-mercapto-1H-1,2,4-triazole; β-mercaptoethanol; 3-amino-5-methylthio-1H-1,2,4-triazole; 1-phenyl-1H-tetrazole-5-thiol; 4-methyl-4H-1,2,4-triazole-3-thiol; 2-pyridinethiol; and 3-mercaptopropionic acid. In some embodiments, the sulfur-containing additive may be free of sulfur-containing organic acids.

[0042] In some embodiments, the sulfur-containing additive may be present in an amount of about 0.01 wt. % or more (e.g., about 0.02 wt. % or more, about 0.04 wt. % or more, about 0.05 wt. % or more, about 0.06 wt. % or more, or about 0.08 wt. % or more) and / or about 0.15 wt. % or less (e.g., about 0.14 wt. % or less, about 0.12 wt. % or less, about 0.1 wt. % or less, about 0.08 wt. % or less, or about 0.07 wt. % or less) of the composition. Without being bound by theory, it is believed that the inclusion of the sulfur-containing additive in the cleaning composition in the above amounts may improve the detergency of the composition for removing post-etch and / or post-ash residue and / or may reduce the etch rate of the cleaning composition for exposed substrate materials (e.g., exposed metal or dielectric materials) that are not intended to be removed during the cleaning process.

[0043] In some embodiments, the cleaning additive may include at least one amino acid (e.g., glycine). The amino acid may be a natural amino acid or a non-natural amino acid (e.g., a synthetic amino acid). The amino acid may be a D-amino acid or an L-amino acid.

[0044] In some embodiments, the amino acid may be present in an amount of about 0.01 wt. % or more (e.g., about 0.02 wt. % or more, about 0.04 wt. % or more, about 0.05 wt. % or more, about 0.06 wt. % or more, or about 0.08 wt. % or more) and / or about 0.15 wt. % or less (e.g., about 0.14 wt. % or less, about 0.12 wt. % or less, about 0.1 wt. % or less, about 0.08 wt. % or less, or about 0.07 wt. % or less) of the composition. Without being bound by theory, it is believed that the inclusion of an amino acid in the cleaning composition in the above amounts may improve the detergency of the composition for removing post-etch and / or post-ash residue and / or may reduce the etch rate of the cleaning composition for exposed substrate materials (e.g., exposed metal or dielectric materials) that are not intended to be removed during the cleaning process.

[0045] In some embodiments, the cleaning compositions of the present disclosure may contain at least one organic acid. The organic acid may be used in the cleaning compositions with or without the presence of the cleaning additives described above (e.g., sulfur-containing additives or amino acids). Organic acids contemplated for use in the cleaning compositions of the present disclosure include carboxylic acids and sulfonic acids. Carboxylic acids contemplated for use in the compositions of the present disclosure include, but are not limited to: monocarboxylic acids; bicarboxylic acids; tricarboxylic acids; monocarboxylic alpha-hydroxy acids and beta-hydroxy acids; bicarboxylic alpha-hydroxy acids and beta-hydroxy acids; and tricarboxylic alpha-hydroxy acids and beta-hydroxy acids. Suitable carboxylic acids include, but are not limited to, citric acid, maleic acid, fumaric acid, lactic acid, glycolic acid, oxalic acid, tartaric acid, succinic acid, and benzoic acid. Sulfonic acids include methanesulfonic acid, trifluoromethanesulfonic acid, ethanesulfonic acid, trifluoroethanesulfonic acid, perfluoroethylsulfonic acid, perfluoro(ethoxyethane)sulfonic acid, perfluoro(methoxyethane)sulfonic acid, dodecylsulfonic acid, perfluorododecylsulfonic acid, butanesulfonic acid, perfluorobutanesulfonic acid, propanesulfonic acid, perfluoropropanesulfonic acid, octyl sulfonic acid, perfluorooctane sulfonic acid, methanedisulfonic acid, 2-methylpropanesulfonic acid, cyclohexylsulfonic acid, camphorsulfonic acid, perfluorohexanesulfonic acid, ethanedisulfonic acid, benzylsulfonic acid, hydroxyphenanthren ... Examples of sulfonic acids include, but are not limited to, methylmethanesulfonic acid, naphthylmethanesulfonic acid, norbornanesulfonic acid, benzenesulfonic acid, chlorobenzenesulfonic acid, bromobenzenesulfonic acid, fluorobenzenesulfonic acid, hydroxybenzenesulfonic acid, nitrobenzenesulfonic acid, 2-hydroxy-5-sulfobenzoic acid, benzenedisulfonic acid, toluenesulfonic acid (e.g., p-toluenesulfonic acid), methylchlorobenzenesulfonic acid, dodecylbenzenesulfonic acid, butylbenzenesulfonic acid, cyclohexylbenzenesulfonic acid, picryl sulfonic acid, dichlorobenzenesulfonic acid, dibromobenzenesulfonic acid, and 2,4,5-trichlorobenzenesulfonic acid.

[0046] In some embodiments, the organic acid may be present in an amount of about 0.01 wt. % or more (e.g., about 0.05 wt. % or more, about 0.1 wt. % or more, about 0.12 wt. % or more, about 0.14 wt. % or more, about 0.16 wt. % or more, about 0.18 wt. % or more, or about 0.2 wt. % or more) and / or about 0.5 wt. % or less (e.g., about 0.4 wt. % or less, about 0.3 wt. % or less, about 0.2 wt. % or less, about 0.18 wt. % or less, or about 0.16 wt. % or less) of the composition. Without being bound by theory, it is believed that the organic acid may act as a chelating agent in the cleaning composition to facilitate removal of post-etch and / or post-ash residues.

[0047] The cleaning compositions of the present disclosure may optionally contain at least one pH adjuster (e.g., an acid or a base) to adjust the pH to about 7 to about 11. In some embodiments, the compositions of the present disclosure may have a pH of about 7 or greater (e.g., about 7.5 or greater, about 8 or greater, or about 8.5 or greater) to about 11 or less (e.g., about 10.5 or less, about 10 or less, about 9.5 or less, about 9 or less). Without being bound by theory, it is believed that a cleaning composition with a pH greater than 11 reduces the cleaning ability of plasma etch residues to a level that is impractical for complete cleaning, while a pH less than 7 increases the etch rate of metal or dielectric materials to an undesirable level. The effective pH may vary depending on the type and amount of ingredients used in the compositions described herein.

[0048] The amount of pH adjuster required, if used, can vary depending on the concentration of other ingredients, particularly hydroxylamine and organic acid, and the molecular weight of the particular pH adjuster used. Typically, the concentration of pH adjuster ranges from about 0.1% to about 3% by weight of the cleaning composition. In some embodiments, the cleaning compositions of the present disclosure contain about 0.1% by weight or more (e.g., about 0.5% by weight or more, about 1% by weight or more, or about 1.5% by weight or more) and / or about 3% by weight or less (e.g., about 2.5% by weight or less, about 2% by weight or less, or about 1.5% by weight or less) of pH adjuster.

[0049] Generally, pH adjusters are metal ion-free (although they may contain trace amounts of metal ion impurities). Suitable metal ion-free pH adjusters include ammonium hydroxide, quaternary ammonium hydroxides, monoamines (including alkanolamines), diamines, triamines (such as diethylenetriaminepentaacetic acid (DTPA)), imines (such as 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) and 1,5-diazabicyclo[4.3.0]-5-nonene), and guanidine salts (such as guanidine carbonate).

[0050] Suitable quaternary ammonium hydroxides include, but are not limited to, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, dimethyldiethylammonium hydroxide, choline, tetraethanolammonium hydroxide, benzyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, and benzyltributylammonium hydroxide.

[0051] Suitable monoamines include, but are not limited to, triethylamine, tributylamine, tripentylamine, ethanolamine, diethanolamine, diethylamine, butylamine, dibutylamine, and benzylamine.

[0052] Additionally, in some embodiments, the cleaning compositions of the present disclosure may optionally contain other additives such as additional pH adjusters, corrosion inhibitors (e.g., substituted or unsubstituted benzotriazoles), surfactants, additional organic solvents, biocides, and antifoam agents.

[0053] Suitable antifoaming agents include polysiloxane antifoaming agents (e.g., polydimethylsiloxane), polyethylene glycol methyl ether polymers, ethylene oxide / propylene oxide copolymers, and glycidyl ether-capped acetylenic diol ethoxylates (such as those described in U.S. Pat. No. 6,717,019, incorporated herein by reference).

[0054] In some embodiments, the cleaning compositions of the present disclosure may be specifically free of one or more additive components, or may be free of any combination of additive components if two or more additive components are specifically excluded. Such excluded components include: oxygen scavengers; quaternary ammonium hydroxides; amines; alkali metal and alkaline earth bases (such as NaOH, KOH, LiOH, magnesium hydroxide, and calcium hydroxide); surfactants other than antifoam agents; fluoride-containing compounds; oxidizing agents (e.g., peroxide, hydrogen peroxide, ferric nitrate, potassium iodate, potassium permanganate, nitric acid, ammonium chlorite, ammonium chlorate, ammonium iodate, ammonium perborate, ammonium perchlorate, ammonium periodate, ammonium persulfate, tetramethylammonium chlorite, chlorine, etc.). tetramethylammonium iodate, tetramethylammonium iodate, tetramethylammonium perborate, tetramethylammonium perchlorate, tetramethylammonium periodate, tetramethylammonium persulfate, urea hydrogen peroxide, and peracetic acid); abrasives; silicates; hydroxycarboxylic acids; non-amino carboxylic acids and polycarboxylic acids; non-azole corrosion inhibitors; guanidine; guanidine salts; inorganic acids (e.g., sulfonic acids, sulfuric acid, sulfurous acid, nitrous acid, nitric acid, phosphorous acid, and phosphoric acid); pyrrolidone; polyvinylpyrrolidone; metal halides; compounds of formula W z MX ywherein W is selected from H, an alkali metal or alkaline earth metal, and a hydroxide base moiety having no metal ion; M is a metal selected from the group consisting of Si, Ge, Sn, Pt, P, B, Au, Ir, Os, Cr, Ti, Zr, Rh, Ru, and Sb; y is 4-6; and a corrosion inhibitor other than those described herein.

[0055] In some embodiments, the cleaning compositions of the present disclosure are not specifically designed to remove the entire photoresist film from a semiconductor substrate. Instead, the cleaning compositions of the present disclosure may be designed to remove all residue after removal of the entire resist by dry or wet stripping methods. Therefore, in some embodiments, the cleaning methods of the present disclosure are preferably used after a dry or wet photoresist stripping process. This photoresist stripping process is typically performed after a pattern transfer process, such as an etching or implant process, or before pattern transfer for mask error correction. The chemical composition of the residue will vary depending on the process performed before the cleaning step.

[0056] Any suitable dry stripping process may be used to remove bulk resist from a semiconductor substrate. Suitable dry stripping processes include: oxygen-based plasma ashing, such as fluorine / oxygen plasma or N2 / H2 plasma; ozone gas treatment; fluorine plasma treatment; high-temperature H2 gas treatment (such as that described in U.S. Pat. No. 5,691,117, the entire contents of which are incorporated herein by reference). Additionally, conventional organic wet stripping solutions known to those skilled in the art may be used to remove bulk resist from a semiconductor substrate, if appropriate.

[0057] A preferred stripping process for use in conjunction with the cleaning method of the present disclosure is a dry stripping process. This dry stripping process is preferably an oxygen-based plasma ashing process. In such a process, most of the photoresist is removed from the semiconductor substrate by a reactive oxygen atmosphere at high temperature (typically 250°C) under vacuum conditions (i.e., 1 Torr). Organic materials are oxidized by this process and removed by the process gas. However, this process does not remove inorganic or organometallic contaminants from the semiconductor substrate. Removal of these residues generally requires subsequent cleaning of the semiconductor substrate with the cleaning composition of the present disclosure.

[0058] In some embodiments, the present disclosure relates to methods for cleaning residue from a semiconductor substrate. Such methods may be carried out, for example, by contacting a semiconductor substrate containing post-etch and / or post-ash residue with a cleaning composition described herein. The methods may further include rinsing the semiconductor substrate with a rinse solvent after the contacting step and / or drying the semiconductor substrate after the rinsing step. In some embodiments, the semiconductor substrate may further comprise a material (e.g., an exposed material) or a layer of a material selected from the group consisting of Cu, Co, W, AlOx, AlN, AlOxNy, Ti, TiN, Ta, TaN, TiOx, ZrOx, HfOx, and TaOx.

[0059] In one embodiment, the cleaning method comprises: (A) providing a semiconductor substrate containing post-etch residue and / or post-ash residue; (B) contacting the semiconductor substrate with a cleaning composition described herein; (C) rinsing the semiconductor substrate with a suitable rinsing solvent; and (D) optionally, drying the semiconductor substrate by any means that removes the rinse solvent and does not impair the quality of the semiconductor substrate; In one embodiment, the cleaning method further comprises forming a semiconductor device (e.g., an integrated circuit device such as a semiconductor chip) from the semiconductor substrate obtained by the above-described method.

[0060] The semiconductor substrate cleaned by this method may contain organic and organometallic residues, but may also contain various metal oxides that must be removed. The semiconductor substrate is typically composed of silicon, silicon germanium, Group III-V compounds such as GaAs, or any combination thereof. The semiconductor substrate may also contain exposed integrated circuit structures such as interconnect features (e.g., metal lines and dielectric materials). Metals and metal alloys used in interconnect features include, but are not limited to, aluminum, aluminum-copper alloys, copper, titanium, tantalum, cobalt, silicon, titanium nitride, tantalum nitride, tungsten, and alloys thereof. The semiconductor substrate may also contain layers of interlayer dielectrics, silicon oxide, silicon nitride, silicon carbide, titanium oxide, and carbon-doped silicon oxide.

[0061] Contacting the semiconductor substrate with the cleaning composition may be accomplished by any suitable method, such as (A) placing the cleaning composition in a bath and immersing and / or submerging the semiconductor substrate in the cleaning composition, (B) spraying the cleaning composition onto the semiconductor substrate, (C) flowing the cleaning composition onto the semiconductor substrate, or (D) a combination thereof. Preferably, the semiconductor substrate is immersed in the cleaning composition.

[0062] The cleaning compositions of the present disclosure can be effectively used at temperatures up to about 90°C (eg, about 25°C to about 80°C, about 30°C to about 60°C, or about 40°C to about 60°C).

[0063] Similarly, cleaning times may vary widely depending on the cleaning method and temperature used. When cleaning by an immersion batch-type process, a suitable time range is, for example, up to about 60 minutes (e.g., about 1 minute to about 60 minutes, about 3 minutes to about 20 minutes, or about 4 minutes to about 15 minutes).

[0064] The cleaning time for one wafer may be in the range of about 10 seconds to about 10 minutes (eg, about 15 seconds to about 9 minutes, about 15 seconds to about 5 minutes, or about 20 seconds to about 2 minutes).

[0065] To further improve the cleaning power of the cleaning compositions of the present disclosure, mechanical agitation means may be used. Suitable agitation means include: circulating the cleaning composition over the substrate; flowing or spraying the cleaning composition over the substrate; and ultrasonic or megasonic agitation during the cleaning process. The semiconductor substrate may be positioned at any angle relative to the ground surface. Horizontal or vertical orientation is preferred.

[0066] The cleaning compositions of the present disclosure can be used in conventional cleaning tools known to those skilled in the art. A significant advantage of the compositions of the present disclosure is that they contain, in whole or in part, relatively non-toxic, non-corrosive, and non-reactive components, making them stable over a wide range of temperatures and process times. The compositions of the present disclosure are chemically compatible with virtually all materials used in existing and proposed semiconductor wafer cleaning process tool configurations for batch and single-wafer cleaning.

[0067] Following cleaning, the semiconductor substrate may be rinsed with a suitable rinse solvent for about 5 seconds to about 5 minutes, with or without agitation. Suitable rinse solvents include, but are not limited to, deionized (DI) water, methanol, ethanol, isopropyl alcohol, N-methylpyrrolidone, gamma-butyrolactone, dimethyl sulfoxide, ethyl lactate, and propylene glycol monomethyl ether acetate. Alternatively, an aqueous rinse agent having a pH greater than 8 (such as dilute aqueous ammonium hydroxide) may be used. Preferred rinse solvents include, but are not limited to, dilute aqueous ammonium hydroxide, DI water, methanol, ethanol, and isopropyl alcohol. The solvent may be applied using a method similar to that used to apply the cleaning compositions described herein. The cleaning composition may be removed from the semiconductor substrate before the rinsing step begins, or may remain in contact with the semiconductor substrate at the beginning of the rinsing step. The temperature used in the rinsing step is preferably between 16°C and 27°C.

[0068] Optionally, the semiconductor substrate is dried after the rinsing step. Any suitable drying means known in the art may be used. Suitable drying means include spin drying, blowing a dry gas onto the semiconductor substrate, heating the semiconductor substrate with a heating means such as a hot plate or an infrared lamp, Marangoni drying, Rotagoni drying, IPA drying, or any combination thereof. Drying times vary depending on the method used, but are generally on the order of 30 seconds to several minutes.

[0069] In some embodiments, a method for manufacturing an integrated device using the cleaning compositions described herein may include the following steps: First, a photoresist layer is applied to a semiconductor substrate. The resulting semiconductor substrate may then be subjected to a pattern transfer process, such as an etching or implant process, to form an integrated circuit. The entire photoresist may then be removed by a dry or wet stripping method (e.g., an oxygen-based plasma ashing process). Residue remaining on the semiconductor substrate may then be removed using the cleaning compositions described herein by the methods described above. The semiconductor substrate may then be processed to form one or more additional circuits on the substrate, or may be processed to form semiconductor chips, for example, by assembly (e.g., dicing and bonding) and packaging (e.g., chip encapsulation).

[0070] All publications (eg, patents, patent application publications, and articles) cited herein are hereby incorporated by reference in their entirety. [Example]

[0071] The present disclosure will be described in more detail with reference to the following examples, which are for illustrative purposes only and should not be construed as limiting the scope of the present disclosure. Percentages listed are by weight (wt%) unless otherwise specified. In the tests, stirring was controlled at 300 revolutions per minute (rpm) using a 1-inch stir bar unless otherwise specified.

[0072] <General Procedure 1> Formula Blend The cleaning compositions of the present disclosure were prepared by mixing an organic solvent and ultra-pure deionized water (DIW) with stirring. After a homogeneous solution was obtained, the remaining ingredients were added. All ingredients used were commercially available and of high purity.

[0073] <General Procedure 2> Cleaning evaluation by beaker test Using multilayer substrates of photoresist / TiOx / SiN / Co / ILD (ILD = interlayer dielectric) or photoresist / TiOx / SiN / W / ILD, which were lithographically patterned and etched in a plasma metal etcher, followed by complete removal of the top photoresist layer by oxygen plasma ashing, the PER (post-etch residue) of the substrates was cleaned with the cleaning compositions described above.

[0074] Test coupons were held using 4-inch long plastic locking tweezers, allowing the coupons to be suspended within a 500 ml glass beaker containing approximately 200 milliliters of the cleaning composition of the present disclosure. Prior to immersion, the coupons were preheated to the desired test temperature (typically 40°C or 60°C, as noted) with controlled agitation. The coupons, held with the plastic tweezers, were then placed in the heated composition with the PER layer facing the stir bar to conduct the cleaning test. The coupons were then left in the cleaning composition for a set period of time (typically 2-5 minutes) while the composition was maintained at the test temperature with controlled agitation. After the desired cleaning time, the coupons were quickly removed from the cleaning composition and placed in a 500 ml plastic beaker filled with approximately 400 ml of gently stirred deionized water at ambient temperature (approximately 17°C). The coupons were placed in a beaker of deionized water for approximately 30 seconds, then quickly removed and rinsed with a stream of ambient-temperature deionized water for approximately 30 seconds. The coupons were immediately exposed to a stream of nitrogen gas from a handheld nitrogen blowgun, which blew any liquid droplets off the coupons and thoroughly dried the coupon device surfaces. After this final nitrogen drying step, the coupons were removed from the plastic tweezers holder and placed, device-side up, in a covered plastic carrier for short-term storage of approximately less than two hours. Scanning electron microscope (SEM) images were then collected of the key structures on the cleaned test coupon device surfaces.

[0075] <General Procedure 3> Beaker test for evaluating material compatibility Blanket Co on silicon substrates, W on silicon substrates, TiOx on SiO2 on silicon substrates, SiN on silicon substrates, ILD on silicon substrates, SiC on silicon substrates, and W alloy on silicon substrates were diced into approximately 1-inch by 1-inch square test coupons for material compatibility testing. The test coupons were first measured for thickness or sheet resistance using a four-point probe CDE Resmap 273 for metal films (Co, W) or by ellipsometry using a Woollam M-2000X for dielectric films (TiOx, SiN, and ILD). The test coupons were then placed in 4-inch long plastic locking tweezers with the side of the coupon with the Co, W, W alloy, TiOx, SiN, SiC, or ILD layer facing the stir bar and treated for 10 minutes as described in the cleaning procedure in General Procedure 2.

[0076] After a final nitrogen drying step, the coupons were removed from the plastic tweezers holder and placed in a covered plastic carrier. The post-treatment thickness or post-treatment sheet resistance on the treated test coupon surface was measured by ellipsometry using a four-point probe, CDE Resmap 273, for metal films (Co, W, and W alloys) or a Woollam M-2000X for dielectric films (TiOx, SiN, SiC, and ILD).

[0077] [Mixing examples FE-1 to FE-3] Table 1 shows formulations FE-1 to FE-3 (containing sulfur-containing additives) prepared according to General Procedure 1. In Tables 1 to 6, "DEGBE" means diethylene glycol butyl ether, "Hex glycol" means hexylene glycol, "MSA" means methanesulfonic acid, and "DTPA" means diethylenetriaminepentaacetic acid.

[0078] [Table 1]

[0079] Examples 1 to 3 Compatibility of the cleaning agent with exposed metal or dielectric Formulations FE-1, FE-2, and FE-3 were tested for cleaning power according to General Procedure 2 and for material compatibility according to General Procedure 3 at 65°C for 4 minutes. Multiple samples of each formulation were tested. The results show that these formulations provide effective removal of post-etch / ash residues. The etch rates (ER) (Angstroms / min) of the cleaning compositions for TiOx, W alloy, Co, SiN, ILD, Al2O3, SiC, and tetraethyl orthosilicate (TEOS) are shown in Table 2.

[0080] [Table 2]

[0081] Table 2 shows that the formulations of the present disclosure (i.e., FE-1, FE-2, and FE-3) did not significantly etch semiconductor materials commonly found in semiconductor devices that were not intended to be removed (e.g., TiOx, Co, W, SiN, ILD, Al2O3, SiC, and TEOS). Furthermore, the sulfolane used in FE-2 appears to have facilitated a reduction in the etch rate of Co.

[0082] [Mixing examples FE-4 to FE-11 and CFE-1 to CFE4] Table 3 shows formulations FE-4 to FE-11 prepared according to General Procedure 1 and comparative formulations CFE-1 to CFE-4.

[0083] [Table 3]

[0084] [Examples 4 to 11 and Comparative Examples 1 to 4] Compatibility of the cleaning agent with the exposed metal Formulations FE-4 through FE-11 and comparative formulations CFE-1 through CFE-4 were tested for cleaning power according to General Procedure 2 and for material compatibility according to General Procedure 3 at 65°C for 4 minutes. The etch rates (ER) (Angstroms / min) of TiOx, W alloy, and Co by the cleaning compositions are shown in Table 4.

[0085] [Table 4]

[0086] Table 4 shows that the comparative formulations (i.e., CFE-1 through CFE-4) that did not contain a boron-containing compound generally had relatively high etch rates for Co. In contrast, the cleaning formulations (i.e., FE-4 through FE-11) that contained a boron-containing compound of the present disclosure had surprisingly low Co etch rates. Therefore, the cleaning formulations of the present disclosure can be used to clean post-etch / post-ash residue without significantly etching exposed Co found on semiconductor devices that is not intended to be removed.

[0087] [Mixing examples FE-12 to FE-13 and CFE-5 to CFE-6] Table 5 shows Formulations FE-12 to FE-13 prepared according to General Procedure 1 and comparative Formulations CFE-5 to CFE-6.

[0088] [Table 5]

[0089] [Examples 12 to 13 and Comparative Examples 5 to 6] Compatibility of the cleaning agent with the exposed metal Formulations FE-12 through FE-13 and comparative formulations CFE-5 through CFE-6 were tested for cleaning power according to General Procedure 2 and for material compatibility according to General Procedure 3 at 65°C for 4 minutes. The etch rates (ER) (Angstroms / min) of TiOx, W alloy, and Co by the cleaning compositions are shown in Table 6.

[0090] [Table 6]

[0091] Table 6 shows that the comparative formulations without boron-containing compounds (i.e., CFE-5 to CFE-6) generally had relatively high etch rates for Co. In contrast, the cleaning formulations with boron-containing compounds of the present disclosure (i.e., FE-12 to FE-13) had surprisingly low Co etch rates. Therefore, the cleaning formulations of the present disclosure can be used to clean post-etch / post-ash residue without significantly etching exposed Co found on semiconductor devices that is not intended to be removed.

[0092] Although the invention has been described in detail with reference to specific embodiments, it will be understood that modifications and variations are within the spirit and scope of what is described and claimed herein. The present invention also includes the following embodiments. <1> 1) at least one redox agent; 2) at least one organic solvent selected from the group consisting of water-soluble alcohols, water-soluble ketones, water-soluble esters, water-soluble sulfones, and water-soluble ethers; 3) at least one boron-containing compound selected from the group consisting of boric acid, boronic acids, and salts thereof; 4) Water and A cleaning composition comprising: <2> pH is about 7 to about 11; <1> The composition described in <3> the at least one redox agent comprises a hydroxylamine; <1> The composition described in <4> the at least one redox agent is about 0.5% to about 20% by weight of the composition; <1> The composition described in <5> Contains two organic solvents, <1> The composition described in <6> The two types of organic solvents are each independently selected from the group consisting of alkylene glycols, alkylene glycol ethers, and sulfones. <5> The composition described in <7> The two organic solvents are each independently selected from hexylene glycol, diethylene glycol butyl ether, and sulfolane. <6> The composition described in <8> The at least one organic solvent is about 60% to about 95% by weight of the composition. <1> The composition described in <9> further comprising at least one organic acid; <1> The composition described in <10> the at least one organic acid comprises a carboxylic acid or a sulfonic acid; <9> The composition described in <11> the at least one organic acid comprises methanesulfonic acid; <10> The composition described in <12> the at least one organic acid is about 0.01% to about 0.5% by weight of the composition; <9> The composition described in <13> the at least one boron-containing compound comprises boric acid; <1> The composition described in <14> The at least one boron-containing compound has the formula (I): RB-(OH) 2 (I) wherein R is C 1 -C 10 is alkyl or aryl; <1> The composition described in <15> R is phenyl; <14> The composition described in <16> the boron-containing compound is about 0.001% to about 0.2% by weight of the composition; <1> The composition described in <17> The water is about 5% to about 28% of the composition. <1> The composition described in <18> A semiconductor substrate containing post-etching residue or post-ashing residue is <1> 4. A method comprising contacting a cleaning composition according to claim 1 with a cleaning composition according to claim 2. <19> the semiconductor substrate further comprises a layer comprising a material selected from the group consisting of Cu, Co, W, AlOx, AlN, AlOxNy, Ti, TiN, Ta, TaN, TiOx, ZrOx, HfOx, and TaOx; <18> The method described below. <20> The method further comprises rinsing the semiconductor substrate with a rinsing solvent after the contacting step. <18> The method described below. <21> Further comprising drying the semiconductor substrate after the rinsing step. <20> The method described below. <22> further comprising forming a semiconductor device from the semiconductor substrate. <18> The method described below.

Claims

1. 1) hydroxylamine in an amount of 5% to 15% by weight of the composition; 2) at least one organic solvent selected from the group consisting of diethylene glycol butyl ether, hexylene glycol, and sulfolane, wherein the at least one organic solvent is in an amount of 70% to 85% by weight of the composition; and 3) at least one boron-containing compound selected from the group consisting of boric acid, phenylboronic acid, and salts thereof, wherein the at least one boron-containing compound is in an amount of 0.005% to 0.12% by weight of the composition; and 4) water in an amount of 5% to 18% by weight of the composition; and and wherein the cleaning composition is non-corrosive to cobalt.

2. 2. The composition of claim 1, wherein the pH is from 7 to 11.

3. 3. The composition of claim 1, wherein the hydroxylamine is 5% to 10% by weight of the composition.

4. The composition according to any one of claims 1 to 3, comprising two types of organic solvents.

5. The composition according to any one of claims 1 to 4, further comprising at least one organic acid.

6. The composition of claim 5 , wherein the at least one organic acid comprises a carboxylic acid or a sulfonic acid.

7. The composition of claim 6 , wherein the at least one organic acid comprises methanesulfonic acid.

8. The composition of any one of claims 5 to 7, wherein the at least one organic acid is 0.01% to 0.5% by weight of the composition.

9. The composition of any one of claims 1 to 8, wherein the at least one boron-containing compound comprises boric acid.

10. The composition of any one of claims 1 to 9, wherein the at least one boron-containing compound comprises phenylboronic acid.

11. The composition of any one of claims 1 to 10, wherein the boron-containing compound is 0.005% to 0.1% by weight of the composition.

12. The composition of any one of claims 1 to 11, wherein the water is from 8% to 18% by weight of the composition.

13. A method comprising contacting a semiconductor substrate containing post-etch or post-ash residue with the cleaning composition of any one of claims 1 to 12.

14. 14. The method of claim 13, wherein the semiconductor substrate further comprises a layer comprising a material selected from the group consisting of Cu, Co, W, AlN, Ti, TiN, Ta, TaN, aluminum oxide, aluminum oxynitride, titanium oxide, zirconium oxide, hafnium oxide, and tantalum oxide.

15. 15. The method of claim 13 or claim 14, further comprising rinsing the semiconductor substrate with a rinsing solvent after the contacting step.

16. The method of claim 15 further comprising drying the semiconductor substrate after the rinsing step.

17. The method of any one of claims 13 to 16, further comprising forming a semiconductor device from the semiconductor substrate.

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