Etching composition

Abstract

The present disclosure relates to etching compositions that can be used to selectively remove sacrificial light absorbing material (SLAM) from a semiconductor substrate, for example, as an intermediate step in a multi-step semiconductor manufacturing process.

Description

Cross-references to related applications

[0001] This application claims priority to U.S. Provisional Application Serial No. 63 / 567,960, filed March 21, 2024, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] This disclosure relates to etching compositions and methods of using etching compositions. Specifically, this disclosure relates to etching compositions that can selectively etch sacrificial light-absorbing materials (SLAM) in the presence of other exposed or underlayer materials, such as metallic conductors (e.g., copper), barrier materials (TiN, SiOC, TaN), or insulating materials (e.g., SiOx, low-k dielectric materials). Background Technology

[0003] In the fabrication of high-performance integrated circuits, dual damascene processes are used to form the multi-level architectures required for these devices. Typically, sacrificial light-absorbing materials (SLAM) are used during the photolithography step to minimize defects when building multi-level microchip architectures. While SLAM has proven useful in this regard, it needs to be removed before final chip fabrication and packaging. Summary of the Invention

[0004] This disclosure relates to compositions and methods for selectively etching sacrificial light-absorbing materials.

[0005] In some embodiments, this disclosure is characterized by a composition comprising at least one polar aprotic organic solvent; at least one quaternary ammonium hydroxide; at least one inorganic base; at least one compound having at least one sulfur-containing moiety; and water.

[0006] In some embodiments, the polar aprotic organic solvent includes dimethyl sulfoxide, sulfolane, and dimethyl sulfone. N,N -Dimethylformamide, N,N -Dimethylacetamide, N 1,3-dimethyl-2-imidazolinone, γ-butyrolactone, propylene carbonate, or 1,3-dimethyl-2-imidazolinone. In some embodiments, the polar aprotic organic solvent is dimethyl sulfoxide. In some embodiments, the amount of the polar aprotic organic solvent is from about 20% to about 60% by weight of the composition. In some embodiments, a mixture of two or more solvents may be used in the compositions disclosed herein.

[0007] In some embodiments, the quaternary ammonium hydroxide is tetramethylammonium hydroxide, tetraethylammonium hydroxide, or tetrabutylammonium hydroxide. In some embodiments, the quaternary ammonium hydroxide is tetramethylammonium hydroxide. In some embodiments, the amount of quaternary ammonium hydroxide is from about 5% by weight to about 15% by weight of the composition.

[0008] In some embodiments, the inorganic base comprises an alkali metal base or an alkaline earth metal base. In some embodiments, the inorganic base is potassium hydroxide. In some embodiments, the amount of the inorganic base is from about 0.1% by weight to about 0.5% by weight of the composition.

[0009] In some embodiments, the compound having at least one sulfur-containing moiety is a mercapto-azole or a mercapto-alcohol. In some embodiments, the compound having at least one sulfur-containing moiety is 1,2,4-triazol-3-thiol, thioglycerol, or 2-mercaptobenzimidazole. In some embodiments, the amount of the compound having at least one sulfur-containing moiety is from about 0.1% by weight to about 0.5% by weight of the composition.

[0010] In some embodiments, the amount of water is from about 40% to about 70% by weight of the composition.

[0011] In some embodiments, the pH of the composition is about 13 to about 14.

[0012] In some embodiments of this disclosure, a method is provided that includes contacting a semiconductor substrate containing a sacrificial light-absorbing material with the composition of this disclosure to substantially remove the sacrificial light-absorbing material. In some embodiments, the method substantially does not remove silicon oxide or low-k dielectric (ILD).

[0013] In some embodiments of this disclosure, articles of manufacture formed by the methods of this disclosure are provided, wherein the articles of manufacture are semiconductor devices. In some embodiments, the semiconductor is an integrated circuit. Detailed Implementation

[0014] As defined herein, unless otherwise indicated, all percentages expressed shall be understood as weight percentages relative to the total weight of the composition. Unless otherwise indicated, ambient temperature is defined as between about 16 and about 27 degrees Celsius (°C). As used herein, the terms “layer” and “film” are used interchangeably.

[0015] Generally, this disclosure is characterized by an etching composition (e.g., an etching composition for selective removal of sacrificial light-absorbing material (SLAM)) comprising (e.g., including or consisting of): at least one quaternary ammonium hydroxide, at least one polar aprotic organic solvent, at least one inorganic base, at least one compound having at least one sulfur-containing moiety, and water. In some embodiments, the etching composition contains only these five types of components.

[0016] In some embodiments, the etching compositions disclosed herein may include at least one (e.g., two, three, or four) quaternary ammonium hydroxide. The quaternary ammonium hydroxide described herein may be tetraalkylammonium hydroxide. In some embodiments, each alkyl group in the tetraalkylammonium hydroxide is independently a C1-C group optionally substituted with OH. 18 The alkyl group, or the alkyl group in tetraalkylammonium hydroxide, may be substituted with an aryl group (e.g., phenyl). Examples of suitable tetraalkylammonium hydroxide or its salts include tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, benzyltrimethylammonium hydroxide (BTMAH), methyltriethylammonium hydroxide, ethyltrimethylammonium hydroxide (ETMAH), dimethyldiethylammonium hydroxide, 2-hydroxyethyltrimethylammonium hydroxide, tetraethanolammonium hydroxide, benzyltriethylammonium hydroxide, benzyltributylammonium hydroxide, or hexadecyltrimethylammonium hydroxide.

[0017] In some embodiments, the amount of at least one quaternary ammonium hydroxide is from at least about 1 wt% (e.g., at least about 2 wt%, at least about 3 wt%, at least about 4 wt%, at least about 5 wt%, at least about 6 wt%, at least about 7 wt%, or at least about 8 wt%) to at most about 15 wt% (e.g., at most about 14 wt%, at most about 12 wt%, at most about 10 wt%, at most about 8 wt%, at most about 7 wt%, at most about 6 wt%, or at most about 5 wt%) of the etching composition of this disclosure. Not wishing to be bound by theory, it is believed that quaternary ammonium hydroxide can promote and enhance the removal of SLAM layers on semiconductor substrates during the etching process.

[0018] In some embodiments, the etching compositions disclosed herein may include at least one (e.g., two, three, or four) compound having at least one sulfur-containing moiety. In some embodiments, the compound having at least one sulfur-containing moiety is a mercapto-azole or a mercapto-alcohol. Examples of compounds having at least one sulfur-containing moiety include, but are not limited to, 1,2,4-triazol-3-thiol, thioglycerol, L-cysteine, mercaptoethanol, or 2-mercaptobenzimidazole.

[0019] In some embodiments, at least one compound having at least one sulfur-containing moiety may be present in the etch composition of this disclosure from at least about 0.1% by weight (e.g., at least about 0.2% by weight, at least about 0.3% by weight, at least about 0.4% by weight, at least about 0.5% by weight, at least about 0.6% by weight, at least about 0.7% by weight, at least about 0.8% by weight, at least about 0.9% by weight, or at least about 1% by weight) to at most about 5% by weight (e.g., at most about 4.5% by weight, at most about 4% by weight, at most about 3.5% by weight, at most about 3% by weight, at most about 2.5% by weight, at most about 2% by weight, at most about 1.5% by weight, at most about 1% by weight, at most about 0.9% by weight, at most about 0.8% by weight, at most about 0.7% by weight, at most about 0.6% by weight, or at most about 0.5% by weight). Not wishing to be bound by theory, it is believed that compounds having at least one sulfur-containing moiety can provide good protection for Cu wires.

[0020] In some embodiments, the inorganic base comprises an alkali metal base or an alkaline earth metal base. In some embodiments, the inorganic base is potassium hydroxide. In some embodiments, the amount of the inorganic base is from about 0.1% by weight (e.g., at least about 0.2% by weight, at least about 0.3% by weight, at least about 0.4% by weight, at least about 0.5% by weight, at least about 0.6% by weight, at least about 0.7% by weight, at least about 0.8% by weight, at least about 0.9% by weight, or at least about 1% by weight) to at most about 5% by weight (e.g., at most about 4.5% by weight, at most about 4% by weight, at most about 3.5% by weight, at most about 3% by weight, at most about 2.5% by weight, at most about 2% by weight, at most about 1.5% by weight, at most about 1% by weight, at most about 0.9% by weight, at most about 0.8% by weight, at most about 0.7% by weight, at most about 0.6% by weight, or at most about 0.5% by weight) of the etching composition of this disclosure.

[0021] Generally, the etching compositions disclosed herein may include water as a solvent. In some embodiments, the water may be deionized and ultrapure, free of organic contaminants, and / or have a minimum resistivity of about 4 to about 17 megohms or at least about 17 megohms. In some embodiments, the amount of water is from at least about 40% by weight (e.g., at least about 42% by weight, at least about 44% by weight, at least about 46% by weight, at least about 48% by weight, at least about 50% by weight, at least about 51% by weight, or at least about 52% by weight) to at most about 70% by weight (e.g., at most about 68% by weight, at most about 66% by weight, at most about 64% by weight, at most about 62% by weight, at most about 60% by weight, at most about 56% by weight, or at most about 54% by weight) of the etching composition. It is not desirable to be bound by theory, but it is believed that if the amount of water exceeds 70% by weight of the composition, it will adversely affect the SLAM etching rate and reduce its removal during the etching process. On the other hand, not wanting to be bound by theory, it is believed that the etch composition disclosed herein should include a certain amount of water (e.g., at least about 50 wt%) to avoid a reduction in etch performance.

[0022] In some embodiments, the etching compositions of this disclosure may include at least one (e.g., two, three, or four) water-soluble organic solvents. As defined herein, a "water-soluble" substance (e.g., a water-soluble organic solvent) means a substance having a solubility of at least 1% by weight in water at 25°C. In some embodiments, the organic solvent may be a polar aprotic solvent. As used herein, the term "polar aprotic solvent" refers to a solvent lacking an acidic proton and having a relatively high dipole moment (e.g., at least 2.7). The water-soluble polar aprotic organic solvent may be a single water-soluble solvent or a mixture of water-soluble solvents in any proportion. Examples of such solvents suitable for use in this disclosure include, but are not limited to, dimethyl sulfoxide, sulfolane, dimethyl sulfone, etc. N,N -Dimethylformamide, N,N -Dimethylacetamide, N 1,3-methylpyrrolidone, γ-butyrolactone, 3-methoxy-3-methyl-1-butanol (MMB), 1,3-dimethyl-2-imidazolinone, and mixtures thereof. In some embodiments, the water-soluble polar aprotic organic solvent is dimethyl sulfoxide, sulfolane, γ-butyrolactone, or... N -Methylpyrrolidone.

[0023] In some embodiments, at least one organic solvent may be at least about 20% by weight (e.g., at least about 25% by weight, at least about 30% by weight, at least about 35% by weight, or at least about 40% by weight) to at most about 50% by weight (e.g., at most about 45% by weight or at most about 40% by weight) of the etching composition.

[0024] In some embodiments, the etch compositions disclosed herein may have a pH of at least about 13 (e.g., at least about 13.1, at least about 13.2, at least about 13.3, at least about 13.4, or at least about 13.5) and / or at most about 14 (e.g., at most about 13.9, at most about 13.8, at most about 13.7, at most about 13.6, or at most about 13.5). It is not desirable to be bound by theory; it is believed that etch compositions with a pH below 13 will not have sufficient SLAM removal rates.

[0025] In some embodiments, the etching compositions of this disclosure may contain additives, such as pH adjusters, corrosion inhibitors, surfactants, additional organic solvents, biocides, and defoamers as optional components. Examples of suitable additives include alcohols (e.g., polyvinyl alcohol and sugar alcohols). Examples of suitable defoamers include polysiloxane defoamers (e.g., polydimethicone), polyethylene glycol methyl ether polymers, ethylene oxide / propylene oxide copolymers, and glycidyl ether-terminated acetylation diol ethoxides (such as those described in U.S. Patent No. 6,717,019, which is incorporated herein by reference). Examples of suitable surfactants may be cationic, anionic, nonionic, and amphoteric surfactants.

[0026] Suitable bases that can be used as pH adjusters include monoamines (including alkanolamines) and cyclic amines. Examples of suitable monoamines include (but are not limited to) triethylamine, tributylamine, tripentylamine, diethylamine, butylamine, dibutylamine, and benzylamine. Examples of suitable alkanolamines include, but are not limited to, monoethanolamine, diethanolamine, triethanolamine, and aminopropyl diethanolamine. Examples of suitable cyclic amines include, but are not limited to, 1,8-diazabicyclo[5.4.0]-7-undecene (DBU), 1,5-diazabicyclo[4.3.0]-5-nonene (DBN), and octahydro-2H-quinazine.

[0027] Generally, the etching compositions of this disclosure can have relatively high SLAM removal while causing minimal damage to Cu lines and other dielectric materials (e.g., ILD, SiOx or SiCO, TiN, TaN) present on the device (i.e., a high ratio of SLAM removal rate to metal and dielectric material removal rate). Additionally, the composition removes dry etching residues present on the device in the form of fluorinated compounds. In some embodiments, the etching composition can have a SLAM removal rate selectivity of at least about 10 (e.g., at least about 20, at least about 40, at least about 50, at least about 60, at least about 80, at least about 100, at least about 150, at least about 200, at least about 250, at least about 300, at least about 350, at least about 400, at least about 450, at least about 500, or at least about 1000) and / or up to about 5000 (e.g., up to about 4000, up to about 3000, up to about 2000, or up to about 1000).

[0028] In some embodiments, the etching compositions disclosed herein may be substantially free of one or more of the additive components, or, if there are more than one additive component, substantially free of any combination thereof. Such components are selected from the group consisting of: organic solvents, polymers (e.g., nonionic, cationic, or anionic polymers), oxygen scavengers, quaternary ammonium compounds (e.g., salts or hydroxides), basic bases (such as NaOH, KOH, LiOH, Mg(OH)2, and Ca(OH)2), surfactants (e.g., cationic, anionic, or nonionic surfactants), defoamers, fluorinated compounds (e.g., fluorinated compounds or fluorinated compounds (such as fluorinated polymers / surfactants)), silicon-containing compounds such as silanes (e.g., alkoxysilanes), nitrogen-containing compounds (e.g., amino acids, amines, imines (e.g., amidines, such as 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) and 1,5-diazabicyclo[4.3.0]non-5-ene (DBN)), The composition contains amides or imides, abrasives (e.g., cerium oxide abrasives, nonionic abrasives, surface-modified abrasives, negatively / positively charged abrasives, or ceramic abrasive complexes), plasticizers, oxidizing agents (e.g., peroxides, such as hydrogen peroxide and periodic acid), corrosion inhibitors (e.g., azole or nonazole corrosion inhibitors), electrolytes (e.g., polyelectrolytes), silicates, cyclic compounds (e.g., azoles (such as diazoles, triazoles, or tetraazoles), triazines, and cyclic compounds containing at least two rings, such as substituted or unsubstituted naphthalenes, or substituted or unsubstituted biphenyl ethers), chelating agents, buffers, acids such as organic acids (e.g., organic sulfonic acids, carboxylic acids such as hydroxycarboxylic acids or polycarboxylic acids) and inorganic acids (e.g., sulfuric acid, sulfurous acid, nitrous acid, nitric acid, phosphoric acid, and phosphoric acid), salts (e.g., halide salts or metal salts), and catalysts (e.g., metal-containing catalysts). In some embodiments, the composition is substantially free of salts other than quaternary ammonium salts. As used herein, "substantially free" of an etching composition means an ingredient not intentionally added to the etching composition. In some embodiments, the etching composition described herein may contain one or more of the above components that are substantially absent from the etching composition, up to about 1000 ppm (e.g., up to about 500 ppm, up to about 250 ppm, up to about 100 ppm, up to about 50 ppm, up to about 10 ppm, or up to about 1 ppm). In some embodiments, the etching composition described herein may be completely free of one or more of the above components.

[0029] The etching compositions disclosed herein can be prepared by simply mixing the components together, or by mixing two or more compositions in a kit (each containing certain components of the etching compositions described herein).

[0030] In some embodiments, this disclosure features a method for etching a semiconductor substrate comprising a SLAM film. The method may include contacting the semiconductor substrate containing the SLAM film with an etching composition of this disclosure to substantially remove the SLAM film. In some embodiments, the semiconductor substrate may include patterns or features on its surface, and the SLAM film is part of the pattern or feature. In some embodiments, the method may further include rinsing the semiconductor substrate with a rinsing solvent after the contact step and / or drying the semiconductor substrate after the rinsing step.

[0031] In some embodiments, the method substantially does not remove the metal conductors (Cu) or dielectric materials (e.g., ILD, SiOx, or SiCO, TiN, TaN) from the semiconductor substrate. In some embodiments, the dielectric material is silicon oxide or silicon nitride. For example, the method does not remove more than about 5% by weight (e.g., more than about 3% by weight or more than about 1% by weight) of the metal conductors or dielectric materials from the semiconductor substrate.

[0032] In some embodiments, the etching method includes the following steps: (A) Provide a semiconductor substrate containing a SLAM film (e.g., a SLAM film in a pattern or feature); (B) Contact the semiconductor substrate with the etching composition described herein; (C) Rinse the semiconductor substrate with one or more suitable rinsing solvents; and (D) Optionally, the semiconductor substrate is dried (e.g., by removing the rinsing solvent by any suitable means without compromising the integrity of the semiconductor substrate).

[0033] In this method, the semiconductor substrate to be etched may contain dry etching residues in the form of fluorinated compounds, which also need to be removed during the etching process.

[0034] The semiconductor substrates (e.g., wafers) described herein are typically composed of silicon, silicon-germanium, III-V compound materials (such as GaAs), or any combination thereof. The semiconductor substrate may additionally contain exposed integrated circuit structures, such as interconnect features (e.g., metal lines and dielectric materials). Metals and metal alloys used for interconnect features include, but are not limited to, aluminum, aluminum alloyed with copper, copper, titanium, tantalum, cobalt, silicon, titanium nitride, tantalum nitride, and tungsten. The semiconductor substrate may also contain layers of interlayer dielectrics, polysilicon, silicon oxide, silicon nitride, silicon-germanium, silicon carbide, titanium oxide, and carbon-doped silicon oxide.

[0035] The semiconductor substrate can be brought into contact with the etching composition by any suitable method, such as placing the etching composition into a tank and immersing and / or submerging the semiconductor substrate in the etching composition, spraying the etching composition onto the semiconductor substrate, allowing the etching composition to flow onto the semiconductor substrate, or any combination thereof.

[0036] The etch composition disclosed herein can be used effectively at temperatures up to about 60°C (e.g., about 40°C to about 60°C, or about 45°C to about 55°C). The etch rate of SLAM increases with increasing temperature within this range, thus processes at higher temperatures can be performed for shorter times. Conversely, lower etch temperatures typically require longer etch times.

[0037] Etching time can vary widely depending on the specific etching method, thickness, and temperature used. When etching in immersion batch processes, a suitable time range is, for example, up to about 5 minutes (e.g., about 1 minute to about 4 minutes, or about 1 minute to about 3 minutes). Etching time for single-wafer processes can range from about 20 seconds to about 4 minutes.

[0038] To further enhance the etching capability of the etch composition of this disclosure, mechanical agitation may be employed. Examples of suitable agitation methods include circulating the etch composition above the substrate during the etching process, flowing the etch composition above the substrate, spraying the etch composition above the substrate, and ultrasonic or ultra-high frequency agitation. The semiconductor substrate may be oriented at any angle relative to the ground. A horizontal or vertical orientation is preferred.

[0039] After etching, the semiconductor substrate may be rinsed with a suitable rinsing solvent for approximately 5 seconds to approximately 5 minutes, with or without agitation. Multiple rinsing steps using different rinsing solvents may be employed. Examples of suitable rinsing solvents include (but are not limited to) deionized (DI) water, methanol, ethanol, isopropanol, etc. N γ-methylpyrrolidone, γ-butyrolactone, dimethyl sulfoxide, ethyl lactate, and propylene glycol monomethyl ether acetate. Alternatively or additionally, an aqueous rinsing solution with pH > 8 (such as a dilute aqueous solution of ammonium hydroxide) may be used. The rinsing solvent may be applied using a method similar to that used with the etching compositions described herein. The etching composition may be removed from the semiconductor substrate before the rinsing step begins, or the etching composition may still be in contact with the semiconductor substrate at the start of the rinsing step. In some embodiments, the temperature used in the rinsing step is 16°C to 27°C.

[0040] Alternatively, the semiconductor substrate may be dried after the rinsing step. Any suitable drying method known in the art may be used. Examples of suitable drying methods include rotary drying, circulating a drying gas over the entire semiconductor substrate, heating the semiconductor substrate with a heating device such as a heating plate or infrared lamp, Maragoni drying, rotagoni drying, IPA drying, and any combination thereof. The drying time will depend on the specific method used, but is typically from about 30 seconds to several minutes.

[0041] In some embodiments, a concentrate of the compositions disclosed herein is considered for use. The concentrate may be, for example, 2× (i.e., twice the concentration of the component in the composition) or 3× (i.e., three times the concentration of the component in the composition). The concentrate is diluted to 1:1 with DIW prior to use. The concentrate can be used to demonstrate cost reduction.

[0042] In some embodiments, the compositions disclosed herein comprise at least one Group II metal cation. Examples of suitable Group II metal cations include Ca. 2+ Mg 2+ 、Sr 2+ And Ba 2+ In some embodiments, at least one Group II metal cation includes Ca. 2+ In some embodiments, the compositions described herein may contain at least about 1 ppm (e.g., at least about 3 ppm, at least about 5 ppm, or at least about 7 ppm) and / or up to about 40 ppm (e.g., up to about 35 ppm, up to about 25 ppm, up to about 20 ppm, or up to about 15 ppm) of a Group II metal cation.

[0043] In some embodiments, the compositions of this disclosure may further include at least one metal cation complexing agent. In some embodiments, the at least one metal cation complexing agent is a carboxylic acid. In some embodiments, the compositions of this disclosure may include at least one carboxylic acid. It is not desirable to be bound by theory, but carboxylic acids are believed to improve the solubility of Group II metal cations in the compositions of this disclosure. In some embodiments, examples of the at least one carboxylic acid contemplated for use in the compositions of this disclosure include, but are not limited to, monocarboxylic acids, dicarboxylic acids, tricarboxylic acids, α-hydroxy acids and β-hydroxy acids of monocarboxylic acids, α-hydroxy acids or β-hydroxy acids of dicarboxylic acids, or α-hydroxy acids and β-hydroxy acids of tricarboxylic acids. In some embodiments, the at least one carboxylic acid includes citric acid, maleic acid, fumaric acid, lactic acid, glycolic acid, oxalic acid, tartaric acid, succinic acid, or benzoic acid. In some embodiments, the carboxylic acid is citric acid.

[0044] In some embodiments of this disclosure, articles of manufacture formed by the methods of this disclosure are provided, wherein the articles of manufacture are semiconductor devices. In some embodiments, the semiconductor device is an integrated circuit. In some embodiments, the etching method described herein further includes forming a semiconductor device (e.g., an integrated circuit device, such as a semiconductor chip) from a semiconductor substrate obtained by the methods described above.

[0045] Example General Program 1 Formulation Mixing Samples of the etching composition are prepared by adding the remaining components of the formulation to a calculated amount of solvent while stirring.

[0046] General Program 2 Materials and Methods The blanket film etching rate was measured using an unpatterned 300 mm diameter wafer, with the blanket film cut into 0.5" × 1.0" test pieces for evaluation. The blanket film materials used for testing included 1) a 1700 Å SiOC film deposited on a Si substrate; 2) an approximately 6000 Å thick ILD film deposited on the 1700 Å SiOC layer on the SiOC substrate; 3) an approximately 1600 Å thick SLAM film deposited on the approximately 6000 Å ILD film on the approximately 1700 Å SiOC film on the SiOC substrate; 4) a approximately 130 Å thick TiN film deposited on a Si substrate; and 5) a approximately 1100 Å thick SiOx film deposited on a Si substrate.

[0047] The thickness of the blanket-coated test specimens before and after processing was measured to determine the blanket-coated etching rate. For SLAM, ILD, SiOC, TiN, and SiOx blanket coatings, the film thickness was measured using Woollam VASE before and after processing via ellipsometry.

[0048] General Procedure 3 Etching evaluation using beaker testing All blanket-coated etching tests were performed in 150 mL PFA vials containing 100 g of sample solution with continuous stirring at 250 rpm. The PFA vials were immersed in 600 mL glass beakers filled with water, which served as a water bath. The beakers were placed on top of a heated stirring plate set at the desired temperature. All blanket-coated test pieces with one side of the blanket exposed to the sample solution were cut into 0.5" × 1.0" square test piece sizes using a diamond scribing tool for beaker-level testing. Each test piece was secured in place using a single 4" long plastic locking tweezers. The test piece was suspended in the 150 mL PFA vial with one edge held by the locking tweezers and immersed in 100 g of test solution while the solution was continuously stirred at 250 rpm at 45°C or 55°C. The test pieces were kept still in the stirred solution until the SLAM was completely removed (15–50 seconds). All other etching rates were calculated based on a 20-minute processing time.

[0049] Immediately after the treatment time in the test solution, the sample tablets were removed from the 150 mL PFA vials and rinsed. Specifically, the tablets were immersed in 300 mL of ultra-high purity deionized (DI) water with gentle agitation for 15 seconds, followed by immersion in 300 mL of isopropanol (IPA) with gentle agitation for 15 seconds, and finally rinsed by immersion in 300 mL of IPA with gentle agitation for 15 seconds. Following the final IPA rinse step, all test tablets were purged with filtered nitrogen using a handheld nitrogen blower. This step powerfully removed all trace amounts of IPA to produce the final dried sample for testing.

[0050] Example 1 Formulation examples 1-6 (FE-1 to FE-6) were prepared according to General Procedure 1 and evaluated according to General Procedures 2 and 3. The formulations and their test results are summarized in Table 1. All etch rates (ER) in this table were measured at 45°C. All compositions of this disclosure exhibited good SLAM removal while minimizing the removal of other layers.

[0051] Table 1 SLAM removal time: +Good; ++Faster; +++Fastest Although the invention has been described in detail with reference to certain embodiments thereof, it should be understood that modifications and variations are within the spirit and scope described and claimed.

Claims

1. A composition comprising: At least one polar aprotic organic solvent; At least one quaternary ammonium hydroxide; At least one inorganic base; At least one compound having at least one sulfur-containing moiety; and water.

2. The composition of claim 1, wherein the polar aprotic organic solvent comprises dimethyl sulfoxide, sulfolane, dimethyl sulfone, N,N -Dimethylformamide, N,N -Dimethylacetamide, N -Methylpyrrolidone, γ-butyrolactone, propylene carbonate or 1,3-dimethyl-2-imidazolinone.

3. The composition of claim 1, wherein the polar aprotic organic solvent comprises dimethyl sulfoxide.

4. The composition of claim 1, wherein the amount of the polar aprotic organic solvent is about 20% to about 60% by weight of the composition.

5. The composition of claim 1, wherein the quaternary ammonium hydroxide comprises tetramethylammonium hydroxide, tetraethylammonium hydroxide, or tetrabutylammonium hydroxide.

6. The composition of claim 1, wherein the quaternary ammonium hydroxide comprises tetramethylammonium hydroxide.

7. The composition of claim 1, wherein the amount of the quaternary ammonium hydroxide is from about 5% to about 15% by weight of the composition.

8. The composition of claim 1, wherein the inorganic base comprises an alkali metal base or an alkaline earth metal base.

9. The composition of claim 1, wherein the inorganic base comprises potassium hydroxide.

10. The composition of claim 1, wherein the amount of the inorganic base is from about 0.1% to about 0.5% by weight of the composition.

11. The composition of claim 1, wherein the compound having at least one sulfur-containing moiety is a mercapto-azole or a mercapto-alcohol.

12. The composition of claim 1, wherein the compound having at least one sulfur-containing moiety is 1,2,4-triazol-3-thiol, thioglycerol, or 2-mercaptobenzimidazole.

13. The composition of claim 1, wherein the amount of the compound having at least one sulfur-containing moiety is about 0.1% to about 0.5% by weight of the composition.

14. The composition of claim 1, wherein the amount of water is about 40% to about 70% by weight of the composition.

15. The composition of claim 1, wherein the pH of the composition is about 13 to about 14.

16. The composition of claim 1, further comprising at least one Group II metal cation.

17. The composition of claim 16, wherein the at least one Group II metal cation comprises Ca. 2+ .

18. The composition of claim 1, further comprising a metal cation complexing agent.

19. The composition of claim 18, wherein the complexing agent is a carboxylic acid.

20. The composition of claim 19, wherein the carboxylic acid comprises citric acid, maleic acid, trans-butenedioic acid, lactic acid, glycolic acid, oxalic acid, tartaric acid, succinic acid, or benzoic acid.

21. A method comprising: A semiconductor substrate containing a sacrificial light-absorbing material is brought into contact with the composition as described in any one of claims 1 to 20 to substantially remove the sacrificial light-absorbing material.

22. The method of claim 21, wherein the method substantially does not remove silicon oxide or silicon nitride.

23. A method comprising: (A) Providing a semiconductor substrate containing a film of sacrificial light-absorbing material; (B) Contact the semiconductor substrate with the etching composition as claimed in claim 1; (C) Rinse the semiconductor substrate with one or more rinsing solvents; and (D) Dry the semiconductor substrate at any location.

24. An article of manufacture formed by the method of claim 21 or 23, wherein the article of manufacture is a semiconductor device.

25. The article of manufacture as claimed in claim 24, wherein the semiconductor device is an integrated circuit.

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