TWI692679B - Photoresist stripper - Google Patents

Abstract

Improved stripper solutions for removing photoresists from substrates are provided that typically have freezing points below about 0 °C and high loading capacities. The stripper solutions comprise dimethyl sulfoxide, quaternary ammonium hydroxide, and an alkanolamine having at least two carbon atoms, at least one amino substituent and at least one hydroxyl substituent, the amino and hydroxyl substituents attached to two different carbon atoms. Some formulations can additionally contain a secondary solvent. The formulations do not contain tetramethylammonium hydroxide. Methods for use of the stripping solutions are additionally provided.

Description

Photoresist stripper

Cross-Reference of Related Applications The present invention claims the priority of US Serial No. 62/609,562 filed on December 22, 2017. This case has the same title, and the entire contents thereof are incorporated herein by reference.

The present invention generally relates to a composition having an effective removal of photoresist from a substrate, and a method of using the composition.

There are many stripper solutions for removing photoresist, such as disclosed in US7632796. As wafer manufacturers increasingly demand improved performance, there is a need for improved stripper solution compositions. The stripper must remain liquid at temperatures below normal room temperature and temperatures often encountered during transportation and storage. In addition, the stripper formulation must have a loading capacity that facilitates the removal of the photoresist material. In addition, little or low metal removal (etching) amount and long stability are required.

In one aspect of the invention, a photoresist stripper solution that effectively removes or strips the photoresist from the substrate is provided. The stripper solution of the present invention has a particularly high load-bearing capacity for the resist material, and the ability to retain liquids when subjected to temperatures lower than the normal room temperature often encountered in transportation, storage, and use in some manufacturing facilities. The freezing point of the composition is sufficiently below 15°C to minimize freezing during transportation and storage. A better formulation has a freezing point below about 0°C.

(I) 其中R¹ 可為H、C₁ -C₄ 烷基或C₁ -C₄ 烷基胺基。對於特佳的式I之烷醇胺，R¹ 係H或CH₂ CH₂ NH₂ 。根據本揭示內容的另一具體實例含有另外的或輔助溶劑。較佳的輔助溶劑包括二醇類及多羥基化合物等。根據本揭示內容的另一具體實例另外含有腐蝕抑製劑。The composition according to the present disclosure generally contains dimethyl sulfoxide (DMSO), quaternary ammonium hydroxide and alkanolamine. A preferred embodiment contains about 20% to about 90% dimethyl sulfoxide, about 1% to about 7% quaternary ammonium hydroxide, and about 1% to about 75% having at least two carbon atoms, at least one amine At least one hydroxy substituent and the amine group and hydroxy substituent are attached to alkanolamines of two different carbon atoms. The preferred quaternary ammonium groups are (C ₁ -C ₈ )alkyl, benzyl, aralkyl, (C ₁ -C ₅ ) alcohol and combinations thereof. A particularly preferred quaternary ammonium hydroxide contains at least 5 carbons and/or may include at least one alkanol group. Quaternary ammonium hydroxide having at least one alkanol group (for example (C ₁ -C ₅ ) alcohol group) includes choline hydroxide and tris(2-hydroxyethyl)methyl ammonium hydroxide. The quaternary ammonium hydroxide may include choline hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide, and dimethyldipropylammonium hydroxide. Quaternary ammonium hydroxide may include choline hydroxide and dimethyldipropylammonium hydroxide. Quaternary ammonium hydroxide does not include tetramethylammonium hydroxide (TMAH). Compared to a composition including tetramethylammonium hydroxide (TMAH), the resulting composition incidentally exhibits reduced toxicity of the human central nervous system. Particularly preferred 1,2-alkanolamines include compounds of the formula:

(I) wherein R ¹ may be H, C ₁ -C ₄ alkyl or C ₁ -C ₄ alkylamine. For a particularly preferred alkanolamine of formula I, R ¹ is H or CH ₂ CH ₂ NH ₂ . Another specific example according to the present disclosure contains additional or auxiliary solvents. Preferred auxiliary solvents include glycols and polyhydroxy compounds. Another specific example according to the present disclosure additionally contains a corrosion inhibitor.

The second aspect of the present disclosure provides a method for removing photoresist and related polymeric materials from a substrate using the novel stripper solution described above. The photoresist can be removed from the selected substrate with the photoresist in the following manner: by contacting the substrate with the stripping solution for a time sufficient to remove the required amount of photoresist; by stripping from the The substrate is taken out of the solution; the stripping solution is washed away from the substrate with a solvent and the substrate is dried.

The third aspect of the present disclosure includes electronic devices manufactured by the disclosed novel methods.

Other features and advantages of the present invention will become apparent from the following more detailed description, combined with an exemplary solution illustrating the principles of the present invention.

In order to promote understanding of the content of the request item, reference will now be made to the specific examples illustrated, and a specific language will be used to describe the content of the request item. It should be understood, however, that there is no intent to limit the scope of the claims, and these changes and further modifications and further applications of the principles as illustrated therein are considered to be commonly thought of by those skilled in the art related to the disclosure.

(I) 其中R¹ 係氫、(C₁ -C₄ )烷基或(C₁ -C₄ )烷基胺基。有些較佳的配方另外含有輔助溶劑。特佳的配方可含有約0.2%至約75%的輔助溶劑。特別有用的輔助溶劑包括下文更詳細描述的二醇類及多羥基化合物。選擇性地，於某些具體實例中，該剝除劑溶液不含或基本上不含輔助溶劑。The composition according to the present invention includes dimethyl sulfoxide (DMSO), quaternary ammonium hydroxide and having at least two carbon atoms, at least one amino group substituent and at least one hydroxyl group substituent and the amine group and hydroxyl group substituent are attached to Alkanolamines with two different carbon atoms. Preferred quaternary substituents include (C ₁ -C ₈ ) alkyl, benzyl and combinations thereof. The preferred composition has a freezing point well below 25°C to minimize solidification during transportation and storage. More preferred formulations have below about 15°C, below about 0°C, below about -5°C, below about -7°C, below about -10°C, below about -12°C, below about -15 ℃, less than about -18 ℃ and / or below the freezing point of about -21 deg.] C and about 15 cm ³ / liter to about 90 cm ³ / liter loading. Formulations with increased alkanolamine content have the advantage of being particularly non-corrosive to carbon steel, and do less damage to typical waste treatment systems and auxiliary equipment than other stripper solutions. A particularly preferred composition contains 1,2-alkanolamine, which has the following formula:

(I) wherein R ¹ is hydrogen, (C ₁ -C ₄ )alkyl or (C ₁ -C ₄ )alkylamine. Some preferred formulations additionally contain auxiliary solvents. A particularly good formula may contain about 0.2% to about 75% auxiliary solvent. Particularly useful auxiliary solvents include glycols and polyols described in more detail below. Optionally, in certain embodiments, the stripper solution is free or substantially free of auxiliary solvents.

The preferred formulation has a freezing point well below 25°C to minimize solidification during transportation and storage. More preferred formulations have below about 15°C, below about 0°C, below about -5°C, below about -7°C, below about -10°C, below about -12°C, below about -15 Freezing point of ℃, below about -18 ℃ and/or below about -21 ℃. Because the preferred stripper solution remains liquid at low temperatures, the need to liquefy drummed coagulated stripper solutions received in cold weather or stored in unheated warehouses before the solution can be used is eliminated or reduced To the lowest. The use of a drum heater to melt the solidified stripper solution takes time, requires additional processing, and may result in incomplete melting and modification of the molten solution composition.

In addition, the composition according to the present disclosure exhibits a high loading capacity, enabling the composition to remove a larger amount of photoresist without solid precipitation. The loading capacity is defined as the amount of cm ³ of photoresist or two-layer material that can be removed per liter of stripper solution before the material is redeposited on the wafer or before the residue is left on the wafer. For example, if a 20-liter stripper solution can remove 300 cm ³ of photoresist from the wafer surface before being re-deposited or left on the wafer, the load capacity is 300 cm ³ /20 liter = 15 cm ³ /liter.

The sum of the weight percentage of DMSO and the weight percentage of alkanolamine in the composition of the present invention may be about 55% to about 97%. In other specific examples, the composition may contain about 55% to about 95%, or about 65% to about 95%, or about 70% to about 97%, or about 75% to about 95%, or about 80% to About 97%, or about 85% to about 97%, or about 85% to about 95%, or about 90% to about 97%, or about 75% to about 90%, or about 75% to about 85%, or About 90% to about 95% DMSO and alkanolamine. In some specific embodiments, the weight percentage of the DMSO is higher than the weight percentage of the alkanolamine, and the DMSO may be stored in the composition in an amount of 5% to about 30%, or 10% to about 30%, Or 10% to about 25% higher than the existing alkanolamine %, or 10% to about 20%. In other compositions, the weight percentage of the DMSO is lower than that of the alkanolamine, and the DMSO may be present in the composition in an amount of 5% to about 30%, or 10% to about 30%, or The% of alkanolamine present is lower by 10% to about 25%, or 10% to about 20%, or 15% to about 20%. Therefore, in some specific examples, the solution may comprise about 20% to about 90%, or about 55% to about 60%, or 30% to about 50%, or 35% to about 45%, or about 55% to About 75% DMSO.

The composition may comprise about 2% to about 10%, or 2% to about 8%, or about 2% to about 6%, or about 2% to about 5%, or about 2% to about 4%, or about 2 % To about 3%, or about 1% to about 7%, or about 1% to about 4% quaternary ammonium hydroxide. Preferred quaternary substituents include (C ₁ -C ₈ )alkyl, benzyl, aralkyl, (C ₁ -C ₅ ) alcohol, and combinations thereof. Some preferred quaternary ammonium hydroxides are choline hydroxides, meaning quaternary ammonium hydroxides having at least one alcohol group attached to nitrogen, such as choline hydroxide and tris(2-hydroxyethyl) hydroxide Methyl ammonium. Another useful quaternary ammonium hydroxide is dimethyldipropylammonium hydroxide. Preferred quaternary ammonium hydroxides are choline hydroxide and dimethyldipropylammonium hydroxide.

Because some of the components of the stripper solution can be provided as an aqueous solution, the composition can additionally contain water. The solution may contain more than 1% by weight, or 2% by weight, or 3% by weight of water. In other specific embodiments, the solution may contain about 1% or about 2% or about 3% to about 7% or about 8% by weight water.

All% provided herein are weight percentages based on the total weight of the composition.

A suitable amount of the alkanolamine required may range from about 1% or 2% to about 75% of the composition. In some specific examples, the alkanolamine is about 40% to about 65%, or about 50% to about 60%, or about 30% to about 40%, or about 5% to about 40% of the solution.

Suitable alkanolamines have at least two carbon atoms and have amine groups and hydroxyl substituents on different carbon atoms. Suitable alkanolamines include, but are not limited to, ethanolamine, N-methylethanolamine, N-ethylethanolamine, N-propylethanolamine, N-butylethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, isopropanolamine, diisopropanolamine, triisopropanolamine, N-methylisopropanolamine, N-ethylisopropanolamine, N-propylisopropanolamine , 2-aminopropan-1-ol, N-methyl-2-aminopropan-1-ol, N-ethyl-2-aminopropan-1-ol, 1-aminopropan-3-ol , N-methyl-1-aminopropane-3-ol, N-ethyl-1-aminopropane-3-ol, 1-aminobutan-2-ol, N-methyl-1-amino Butan-2-ol, N-ethyl-1-aminobutan-2-ol, 2-aminobutan-1-ol, N-methyl-2-aminobutan-1-ol, N-ethyl 2-aminobutan-1-ol, 3-aminobutan-1-ol, N-methyl-3-aminobutan-1-ol, N-ethyl-3-aminobutan-1-ol Alcohol, 1-aminobutan-4-ol, N-methyl-1-aminobutan-4-ol, N-ethyl-1-aminobutan-4-ol, 1-amino-2-methyl Propan-2-ol, 2-amino-2-methylpropan-1-ol, 1-aminopentan-4-ol, 2-amino-4-methylpentan-1-ol, 2-amine Hexan-1-ol, 3-aminoheptan-4-ol, 1-aminooctan-2-ol, 5-aminooctan-4-ol, 1-aminopropan-2,3-diol, 2-aminopropyl-1,3-diol, tris(oxymethyl)aminomethane, 1,2-diaminopropan-3-ol, 1,3-diaminopropan-2-ol and 2 -(2-aminoethoxy) ethanol.

When used, the auxiliary solvent may comprise about 0.2% to about 35%, or about 0.2% to about 30%, or about 0.2% to about 25%, or about 0.2% to about 20%, or about 0.2% of the composition To about 15%, or about 0.2% to about 12%, or about 5% to about 12%. The auxiliary solvent may include alcohols, or polyhydroxy compounds, or a combination of two or more of these.

The auxiliary solvents alcohols and polyhydroxy compounds have two or more hydroxyl groups and do not contain ester groups, amine groups or ether groups. The alcohol or polyhydroxy compound may be aliphatic, cycloaliphatic, cyclic, or aromatic, but ideally aliphatic or cycloaliphatic. The alcohol or polyhydroxy compound may be saturated or unsaturated, and desirably has one or less unsaturated bonds, or no unsaturated bonds. The alcohol and polyhydroxy compound ideally contain no heteroatoms. The alcohol and polyhydroxy compound ideally contain only carbon atoms, oxygen atoms and hydrogen atoms.

As examples of auxiliary solvent alcohols, linear alcohols and branched chain alcohols and aromatic alcohols may be mentioned. To exemplify the alcohol of the solution may include methanol, ethanol, propanol, isopropanol, butanol, third butanol, third pentanol, 3-methyl-3-pentanol, 1-octanol, 1- Decanol, 1-undecyl alcohol, 1-dodecyl alcohol, 1-tridecyl alcohol, 1-tetradecyl alcohol, 1-pentadecanol, 1-hexadecanol, 9-hexadecane En-1-ol, 1-heptadecanol, 1-octadecyl alcohol, 1-nonadecanol, 1-eicosanol, 1-twenty-alkanol, 1-behenyl alcohol, 13-docosaen-1-ol, 1-tetracosanol, 1-hexacosanol, 1-tracadecanol, 1-octacosanol, 1-tricosanol , 1-tridodecyl alcohol, 1-tridecyl alcohol, cetearyl alcohol, furan methanol, tetrahydrofuran methanol. In an illustrative example, the solution may include one or more of furan methanol, tetrahydrofuran methanol, third butanol, or 3-methyl-3-pentanol.

As described above, the auxiliary solvent may be a polyhydroxy compound having two or more hydroxyl groups. The polyhydroxy compound desirably has no more than 500, or no more than 400, or no more than 350, or no more than 300, or no more than 275, or no more than 250, or no more than 225, or no more than 200, or no more than 175, Or a molecular weight of not more than 150, or not more than 125, or not more than 100, or not more than 75.

The polyhydroxy compound as an auxiliary solvent may include ethylene glycol; 1,2-propanediol (propylene glycol); 1,3-propanediol; 1,2-,3-propanetriol; 1,2-butanediol; 1,3- Propylene glycol; 2,3-butanediol; 1,4-butanediol; 1,2,3-butanetriol; 1,2,4-butanetriol; 1,2-pentanediol; 1,3- Pentanediol; 1,4-pentanediol; 2,3-pentanediol; 2,4-pentanediol; 3,4-pentanediol; 1,2,3-pentanetriol; 1,2, 4-pentanetriol; 1,2,5-pentanetriol; -1,3,5-pentanetriol; etohexadiol; p-methane-3,8-polyhydroxy compound; 2-methyl -2,4-pentanediol; 2,2-dimethyl-1,3-propanediol; glycerin; trimethylolpropane; xylitol; arabinitol; 1,2- or 1,3-cyclopentane Glycol; 1,2- or 1,3-cyclohexanediol; 2,3-norbornanediol; 1,8-octanediol; 1,2-cyclohexanedimethanol; 1,3-cyclo Hexane dimethanol; 1,4-cyclohexane dimethanol; 2,2,4-trimethyl-1,3-pentanediol; hydroxypivalyl hydroxypivalate; 2-methyl 1,3-propanediol; 2-butyl-2-ethyl-1,3-propanediol; 2-ethyl-2-isobutyl-1,3-propanediol; 1,6-hexanediol; 2 ,2,4,4-tetramethyl-1,6-hexanediol; 1,10-decanediol; 1,4-benzenedimethanol; hydrogenated bisphenol A; 1,1,1-trimethylol Propane; 1,1,1-trimethylolethane; pentaerythritol; erythritol; threitol; dipentaerythritol; and sorbitol, etc., and two or more of the above-mentioned polyhydroxy compounds and polyhydroxy compounds Of the combination.

In an illustrative example, the solution may include ethylene glycol, 1,2-propanediol (propylene glycol), 1,3-propanediol, 1,4-pentanediol, 1,2-butanediol, or 1,3-butane One or more of the secondary polyhydroxyl solvents of the diol.

The composition may optionally contain one or more corrosion inhibitors. Suitable corrosion inhibitors include, but are not limited to, aromatic hydroxy compounds, such as catechol and resorcinol; alkyl catechols, such as methyl catechol, ethyl catechol and Third butyl catechol, phenols and gallogol (pyrogallol); aromatic triazoles such as benzotriazole; alkyl benzotriazoles; sugar alcohols such as glycerol and sorbitol; carboxylic acids such as formic acid , Acetic acid, propionic acid, butyric acid, isobutyric acid, oxalic acid, malonic acid, succinic acid, glutaric acid, fumaric acid, maleic acid, benzoic acid, phthalic acid, 1,2 ,3-Pyromellitic acid, glycolic acid, lactic acid, malic acid, citric acid, acetic anhydride, phthalic anhydride, fumaric anhydride, succinic anhydride, salicylic acid, gallic acid and gallic acid Esters such as methyl gallate and propyl gallate; metal salts such as copper (II) nitrate; copper (II) bromide; copper (II) chlorate; copper (II) chloride; fluorosilicone Copper(II) acid; Copper(II) formate; Copper(II) selenate; Copper(II) sulfate; Organic salts of the above-mentioned carboxyl-containing organic compounds, alkaline substances such as ethanolamine, trimethylamine, diethylamine And pyridines such as 2-aminopyridine, etc.; and chelating compounds such as phosphoric acid-based chelating compounds (including 1,2-propanediaminetetramethylenephosphonic acid and hydroxyethanephosphonic acid), carboxylic acid-based chelating compounds Compounds (e.g. ethylenediaminetetraacetic acid and its sodium and ammonium salts, dihydroxyethylglycine and nitrilotriacetic acid), amine chelating compounds (e.g. bipyridine, tetraphenylporphyrin And phenanthroline) and oxime chelating compounds (such as dimethylglyoxime and diphenylglyoxime). A single corrosion inhibitor can be used, or a combination of corrosion inhibitors can be used. The amount of corrosion inhibitor has been proved It ranges from about 1 ppm to about 10%. In a specific example, the solution may contain about 0.05% by weight to about 7% by weight of the first corrosion inhibitor and about 0.001% by weight to about 3% by weight of the second corrosion inhibitor Formulation. In other specific embodiments, the solution may contain at least 0.05 weight percent, or at least 0.1 weight percent, or at least 1 weight percent, and/or less than about 3 weight percent and/or less than about 7 weight percent of the first corrosion inhibitor Formulation. In other specific embodiments, the solution may contain at least 0.001 weight percent, or at least 0.01 weight percent, or at least 0.1 weight percent, and/or less than about 1 weight percent and/or less than about 2 weight percent and/or less than about 3 weight percent of the second corrosion inhibitor. The first and second corrosion inhibitors are different. Both the first corrosion inhibitor and the second corrosion inhibitor can be selected from the corrosion inhibitors described above. In a specific example, The one or more corrosion inhibitors may include copper (II) nitrate; copper (II) bromide; copper (II) chlorate; copper (II) chloride; copper (II) fluorosilicate; copper (II) formate ; Copper (II) selenate; Copper (II) sulfate alone or in combination with at least one of the above corrosion inhibitors. Among them, the one or more corrosion inhibitors may be copper (II) nitrate; copper (II) bromide; copper (II) chlorate; copper (II) chloride; copper (II) fluorosilicate; copper formate ( II); copper (II) selenate; copper (II) sulfate and/or resorcinol. In another preferred embodiment, the corrosion inhibitor may include copper (II) nitrate and resorcinol.

The stripping formulation may also contain one or more surfactants as needed, usually in an amount of about 0.01% to about 3% or about 0.01 to about 1% by weight. Preferred optional surfactants include fluorosurfactants. An example of a preferred fluorosurfactant is DuPont FSO (containing polyethylene glycol (50%), ethylene glycol (25%), 1,4-dioxane (<0.1%), water 25% fluorine Telomer B monoether). Another example of a preferred fluorosurfactant is DuPont, Capstone, FS-10 (30% perfluoroalkylsulfonic acid in water).

With regard to contact with the substrate, a preferred temperature of at least 50°C is preferred, however, for most applications, a temperature of about 50°C to about 75°C is more preferred. For specific applications where the substrate is sensitive or requires a longer removal time, it is suitable for lower contact temperatures. For example, when the substrate is reprocessed, it may be appropriate to maintain the stripper solution at a temperature of at least 20°C for a longer time to remove the photoresist and avoid damage to the substrate.

When the substrate is impregnated, the agitation of the composition incidentally promotes the removal of the photoresist. Agitation can be achieved by mechanical stirring, circulation, or by bubbling inert gas through the composition. When the required amount of photoresist is removed, the substrate is removed in contact with the stripper solution, and rinsed with water or alcohol. Deionized water is the preferred form of water and isopropyl alcohol is the preferred alcohol. For substrates with components subject to oxidation, rinsing is preferably carried out under an inert atmosphere. The preferred stripper solvent according to the present disclosure has improved photoresist material loading capacity compared to existing commercial products, and is capable of treating a larger number of substrates with a specific volume of stripper solution.

The stripper solution provided in this disclosure can be used to remove polymeric flame retardant materials that exist in single-layer or certain types of double-layer resists. For example, the double-layer resist usually has a first inorganic layer covered by a second polymerizable layer or may have a dipolymerizable layer. Using the method taught below, a single layer of polymerizable resist monolayer can be effectively removed from a standard wafer with a single polymer layer. This method can also be used to remove a single polymer layer from a wafer with a double layer consisting of a first inorganic layer and a second or outer polymer layer. Finally, the two polymer layers can be effectively removed from the wafer with the double layer composed of the two polymerizable layers.

This disclosure describes a chemical solution for removing thick photoresist, which may be about 10 μm to about 200 μm or greater, or about 15 μm to 200 μm, or about 20 μm to about 200 μm in advanced packaging applications for semiconductor devices Of resistance. In other cases, the chemical solution can be used to remove photoresist from about 1 μm to about 200 μm or greater, or from about 2 μm to 200 μm, or from about 3 μm to about 200 μm. In a specific example, the solution contains DMSO, monoethanolamine (MEA), water, quaternary ammonium hydroxide, and at least one corrosion inhibitor. The quaternary ammonium hydroxide and stripper solutions of the present invention are substantially free of TMAH. The ammonium hydroxide is preferably choline hydroxide or dimethyldipropylammonium hydroxide. Substantially free means that the content is less than 1 percent, or less than 0.1 percent, or less than 0.01 percent or less than 0.001 percent. Substantially does not include TMAH. In another specific example, the quaternary ammonium hydroxide does not contain TMAH. The solution also contains a surfactant if necessary. The solution may contain more than 1 or 3% by weight of water. In a specific example, the solution may contain about 1% by weight or 2% by weight or 3% by weight to about 7% by weight or 8% by weight of water. In another specific embodiment, the ratio of the amount of water in the solution to the amount of quaternized ammonium hydride is greater than about 1.2, greater than about 1.5, greater than about 1.8, greater than about 2.0, greater than about 2.2, and/or greater than about 2.5. In an alternative specific example, the ratio of the amount of water in the solution to the amount of ammonium hydroxide is about 1.2 to about 1.5. The solution may also contain more than 25% by weight of MEA.

Some specific examples of the composition of the present invention may be substantially free of, or free of (as those terms defined above) any combination of one or more of the following: nitrogen-containing solvents, bis-choline salts, tri-choline salts, Oxyammonium compounds, hydroxylamines and their derivatives, methyldiethanolamine, aminoethylethanolamine, glycol ethers, hydrogen peroxide, oxidants, organic acids, inorganic acids, inorganic bases, metal hydroxides, dihydrate Alcohols, polyols, NMP, surfactants, metal-containing compounds, sugar alcohols and aromatic hydroxy compounds and any combination thereof. In other specific examples, the composition is substantially free (or free) of sodium and/or calcium and/or aminocarboxylic acids and/or alcohols and/or ethylenediamine and/or ethyltriamine and /Or thiophenol. In some embodiments, the composition disclosed herein is formulated to be substantially free of or free of at least one of the following chemical compounds: alkyl mercaptan and organosilane. In some specific examples, the compositions disclosed herein are formulated to be substantially free of or free of one or more of the following: halogen-containing compounds, which may, for example, be substantially free of or free of one or more of the following: Compounds containing fluorine, bromine, chlorine or iodine. In other specific examples, the composition may be substantially free or free of sulfonic acid and/or phosphoric acid and/or sulfuric acid and/or nitric acid and/or hydrochloric acid. In other specific examples, the composition may be substantially free or free of sulfate and/or nitrate and/or sulfite and/or nitrite. In other specific examples, the composition may be substantially free or free of: ethyldiamine, sodium-containing compounds and/or calcium-containing compounds and/or manganese-containing compounds or magnesium-containing compounds and/or chromium-containing compounds and/or Or sulfur compounds and/or silane compounds and/or phosphorus compounds. Some specific examples may be substantially free or free of surfactant. Some specific examples may be substantially free or free of amphoteric salts and/or cationic surfactants and/or anionic surfactants and/or zwitterionic surfactants and/or nonionic surfactants Agent. Some specific examples may be substantially free or free of imidazole and/or anhydride. Some specific examples may be substantially free or free of pyrrolidone and/or acetamide. Some specific examples may be substantially free or free of any amines. Some specific examples may be substantially free or free of peroxy-compound and/or peroxide and/or persulfate and/or percarbonate and their acids and salts. Some specific examples may be substantially free or free of iodate and/or perborate and/or borate and/or percarbonate and/or peroxyacid and/or cerium compounds and/or cyanide and/or Iodic acid and/or ammonium molybdate and/or ammonia. The components that may not be included in the composition of the present invention may be any combination of the components, like all combinations described herein.

The composition of the present invention may also include one or more of the following additives: chelating agents, chemical modifiers, dyes, biocides, and other additives. The additive can be added to such an extent that it does not adversely affect the performance of the composition, and generally the amount is up to about 5% by weight of the composition. In other specific embodiments, the composition is substantially free or free of chelating agents, dyes, biocides, and/or other additives.

In Example 1, various stripping compositions were used to remove thick spin-on photoresist from silicon wafers plated with Cu pillars and Sn/Ag solder caps. The removal of the resist is carried out in the beaker using a dipping process.

For this dipping process, a semiconductor wafer sample cut to the sample size is processed in a beaker. The beaker was filled with 100 mL of the stripping composition and heated to a target temperature of 70°C. When the stripping composition is at the target temperature, the sample is placed in the sample holder of the beaker and slightly stirred by a stir bar. Keep the temperature at the target temperature of 70°C throughout the manufacturing process. After a total treatment time of 60 minutes, the sample was removed from the beaker, rinsed with deionized water and IPA, and dried with a stream of air.

For the experiments described below, the phenomenon of resist removal was observed and noted accordingly. If all the resist is removed from the surface of the wafer sample, the removal of the resist is defined as "clean"; if at least 95% of the resist is removed from the surface instead of all the resist, it is defined as "approximately clean"; And if at least about 80% of the resist is removed from the surface but less than 95% of the resist is defined as "local cleaning".

Apply the following abbreviations to the various compositions listed below: DMSO = dimethyl sulfoxide; MEA = monoethanolamine; MMB = 3-methoxy-3-methyl-1-butanol; TMAH = tetramethyl hydroxide Ammonium; PG = propylene glycol; DMDPAH = dimethyldipropylammonium hydroxide; THFA = tetrahydrofuran methanol; DB = diethylene glycol monobutyl ether; CH = choline hydroxide.

Table 1 lists various original and comparative stripping compositions.

Example 1

Table 2 lists the stripping compositions tested in Example 1 using the dip process and semiconductor wafers with thick photoresist and copper-plated pillars and Sn/Ag solder caps. The heating temperature and time of all compositions in Table 2 are 70°C and 60 minutes, respectively.

In Example 2, various stripping compositions were used to remove a 40 μm-thick negative dry film photoresist from a silicon wafer plated with Cu features. The resist was removed in a beaker using a dipping process.

For this dipping process, a semiconductor wafer sample cut to the sample size is processed in a beaker. The beaker was filled with 100 mL of the stripping composition and heated to a target temperature of 70°C. When the stripping composition is at the target temperature, the sample is placed in the sample holder of the beaker and slightly stirred by a stir bar. Keep the temperature at the target temperature of 70°C throughout the manufacturing process. After a total treatment time of 30 to 60 minutes, the sample was removed from the beaker, rinsed with deionized water and IPA, and dried with a stream of air.

For the experiments described below, the phenomenon of resist removal was observed and noted accordingly. If all the resist is removed from the surface of the wafer sample, the removal of the resist is defined as "clean"; if at least 95% of the resist is removed from the surface instead of all the resist, it is defined as "approximately clean"; And if at least about 80% of the resist is removed from the surface but less than 95% of the resist is defined as "local cleaning".

Example 2

Table 3 lists the stripping compositions tested in Example 2 using this dipping process and semiconductor wafers with thick dry film photoresist and Cu-plated features. The heating temperature in Table 3 is 70°C.

Example 3

In Example 3, various stripping compositions were used to evaluate metal corrosion. The metal corrosion test is carried out using a dipping process.

For this immersion process, a sample-sized semiconductor wafer sample containing a Cu layer of known thickness and a sample-sized semiconductor wafer sample containing a Sn layer of known thickness are processed in a beaker. Thick layers of Cu and Sn are deposited on the wafer by physical vapor deposition. The beaker was filled with 100 mL of the stripping composition and heated to a target temperature of 70°C. When the stripping composition is at the target temperature, a sample having each metal on it and having a known surface area is placed in the sample holder of the beaker and agitated by a stir bar. Keep the temperature at the target temperature of 70°C throughout the manufacturing process. After a total treatment time of 60 or 120 minutes, the sample was removed from the beaker.

A sample of the solution was collected, and the concentration of dissolved Cu and Sn was measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). Before the solution was heated and used to treat the sample, the dissolved Cu and Sn concentrations were also measured in the solution sample as a control. The change in the dissolved Cu or Sn concentration indicates the amount of metal dissolved by the formulation during the sample cleaning process. A small change in dissolved metal concentration of ≤10 ppm compared to the control concentration indicates very good metal compatibility, that is, low metal etching rate.

Table 4 lists the ICP-AES measurement results of the dissolved Cu and Sn concentrations of Example 3 obtained using the immersion process. The control quantities of Cu and Sn are listed in the third column and the fourth column of Table 4, respectively, and the actual measurement is listed in the next 4 columns if marked. The concentration of ≤10 ppm is preferably a target of 0 ppm compared to the control concentration. The heating temperature of all compositions in Table 4 is 70°C, and the processing time is 60 minutes and 120 minutes, respectively. The amount of Cu or Sn dissolved in the stripper solution (removed from the wafer sample) can be obtained by subtracting the control amount from the actual measurement. For example, for Formulation 1: 2 ppm (2 ppm minus 0 ppm) of Cu was dissolved by the stripper solution at 70°C and 60 minutes; 3.8 ppm (4.3 ppm minus 4.3 ppm) at 70°C and 60 minutes 0.5 ppm) of Sn was dissolved by the stripper solution.

Table 5 lists the freezing points of various formulations, and lower temperatures are better for improved storage and transportation capabilities.

Example 4

In Example 4, a test was conducted to evaluate the stability of quaternary ammonium hydroxide. The stability was tested by heating the 100 ml formulation in the beaker to a target temperature of 70°C. The target temperature is maintained for 8 hours. A small sample was taken from the beaker at a target interval of 2 hours and tested by acid-base titration.

表2

表3

表4

表5

表6 隨時間測量的重量百分比

Table 6 lists the change in weight% of alkali content measured by acid-base titration at each target interval up to 8 hours. The smaller weight% change rate for each target interval is better and represents a more stable formulation. The improved formulation stability provides users with a longer product shelf life, longer product bath life during use, and improved photoresist loading capacity. The last line in the table records the change in alkali weight% from time 0 to 8 hours and indicates that formula 10 has the smallest change. Table 1

Table 2

table 3

Table 4

table 5

Table 6 Weight percentage measured over time

Although the present invention has been described with reference to one or more specific examples, those of ordinary skill in the art will understand that various changes can be made without departing from the scope of the present invention and that elements can be replaced with equivalents. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope of the invention. Therefore, it is intended that the present invention is not limited to the specific specific examples disclosed as the best mode for carrying out the present invention, but the present invention will include all specific examples falling within the scope of the appended patent application. In addition, all numerical values determined in the embodiments should be interpreted as precise values and approximate values are clearly confirmed. In addition, any use of "having", "including" or "containing" in the specification and patent application includes the more narrowly defined predicate: "essentially composed of..." and "consisting of... .Composed", as if the predicate was clearly written after "having", "comprising" or "containing" and other feasible solutions. In addition, the use of the article "a" or "the" to describe any component of the stripper composition should be interpreted as "one or more than one" wherever it appears in the specification and patent application Instead.

Claims (20)

A stripping agent solution for removing photoresist from a substrate, comprising: about 20% to about 90% by weight of dimethyl sulfoxide; about 1% to about 7% by weight of quaternary ammonium hydroxide; About 1% by weight to about 75% by weight alkanolamine; about 0.001% by weight to about 7% by weight corrosion inhibitor; and about 1% by weight to about 8% by weight water; wherein the solution appears below about 0 degrees Celsius Freezing point; and wherein the quaternary ammonium hydroxide is substantially free of tetramethylammonium hydroxide, and the quaternary ammonium hydroxide includes choline hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide or hydrogen At least one of dimethyldipropylammonium oxide. As in the solution of claim 1, the quaternary ammonium hydroxide includes choline hydroxide. As in the solution of claim 1, the quaternary ammonium hydroxide includes tris(2-hydroxyethyl)methylammonium hydroxide. For example, in the solution of claim 1, the alkanolamine is present in an amount of about 25% to about 75% by weight. For example, in the solution of claim 4, the alkanolamine includes monoethanolamine. For example, the solution in claim 4 of the patent application, wherein the dimethyl sulfoxide has an amount of about 55% to about 60% by weight; wherein the quaternary ammonium hydroxide has an amount of about 1.5% to about 3.5% by weight Wherein the alkanolamine is present in an amount of about 30% to about 40% by weight; and wherein the first corrosion inhibitor is present in an amount of about 0.001% to about 3% by weight. As in the solution of claim 6, the alkanolamine includes monoethanolamine. For example, in the solution of claim 7, the first corrosion inhibitor is selected from the group consisting of resorcinol, glycerin, sorbitol, and copper (II) nitrate. For example, the solution of claim 7, wherein the first corrosion inhibitor is selected from copper (II) nitrate; copper (II) bromide; copper (II) chlorate; copper (II) chloride; fluorosilicic acid Copper (II); copper (II) formate; copper (II) selenate; and/or copper (II) sulfate and resorcinol. As in the solution of claim 8, the first corrosion inhibitor is present in an amount between about 0.001% and about 0.1% by weight. For example, the solution according to item 1 of the patent application scope further includes about 0.01% to about 3% by weight of a surfactant. As in the solution of claim 1, the first corrosion inhibitor is selected from the group consisting of resorcinol, glycerin, sorbitol, and copper (II) nitrate. For example, the solution according to item 12 of the patent application scope further includes about 0.001% by weight to about 3% by weight of the second corrosion inhibitor. A solution as claimed in item 13 of the patent application, wherein the second corrosion inhibitor is different from the first corrosion inhibitor and is selected from the group consisting of resorcinol, glycerin, sorbitol, and copper (II) nitrate . For example, the solution of claim 14 of the patent application, wherein the dimethyl sulfoxide has an amount of about 35% to about 45% by weight, and the quaternary ammonium hydroxide has an amount of about 1.5% to about 3.5% by weight, The alkanolamine is present in an amount of about 50% to about 60% by weight, the first corrosion inhibitor is present in an amount of about 0.05% to about 3% by weight, and the second corrosion inhibitor is present in an amount of about 0.001 Amounts from wt% to about 0.1 wt%. For example, the solution in the scope of patent application item 15, wherein the alkanolamine includes monoethanolamine. If the solution of patent application item 1, wherein the freezing point is lower than about Celsius -15 degrees. For example, the solution of patent application item 1, where the freezing point is lower than -21 degrees Celsius. A stripping agent solution for removing photoresist from a substrate, comprising: about 20% to about 90% by weight of dimethyl sulfoxide; about 1% to about 7% by weight of quaternary ammonium hydroxide; About 1% to about 75% by weight alkanolamine; about 0.001% to about 7% by weight corrosion inhibitor; and water; wherein the ratio of the amount of water to the amount of quaternary ammonium hydroxide is greater than about 1.2; wherein the solution Exhibits a freezing point below about 0 degrees Celsius; and wherein the quaternary ammonium hydroxide is substantially free of tetramethylammonium hydroxide, and the quaternary ammonium hydroxide includes choline hydroxide, tris(2-hydroxyethyl hydroxide) Group) at least one of methylammonium or dimethyldipropylammonium hydroxide. A method for cleaning a resist from a substrate, comprising: contacting the resist on the substrate with a stripping solution for a time sufficient to remove the required amount of resist and removing the substrate from the stripping solution, wherein the stripping The solution contains: about 20% to about 90% by weight of dimethyl sulfoxide; about 1% to about 7% by weight of quaternary ammonium hydroxide; about 1% to about 75% by weight of alkanolamine; about 0.001 Weight percent to about 7 weight percent corrosion inhibitor; and about 1 weight percent to about 8 weight percent water; wherein the solution exhibits a freezing point below about 0 degrees Celsius; and Wherein the quaternary ammonium hydroxide is substantially free of tetramethylammonium hydroxide, and the quaternary ammonium hydroxide includes choline hydroxide, tris(2-hydroxyethyl)methylammonium hydroxide or dimethyldipropylhydroxide At least one of the basic ammonium.