Cleaning liquid composition

Abstract

The present invention addresses the problem of providing a cleaning liquid composition that exhibits good detergency to post-CMP residues, such as slurry-derived abrasive grains and organic residues containing molybdenum (Mo), on a substrate having a molybdenum (Mo)-containing film and minimizes deformation due to corrosion of molybdenum (Mo) wiring.　The present invention relates to a cleaning liquid composition for cleaning a substrate having a molybdenum (Mo)-containing film, the cleaning liquid composition containing one or more reducing agents and water, and having a pH of 7 or less.

Description

Cleaning composition

[0001] The present invention relates to a cleaning liquid composition used for cleaning a substrate having a molybdenum (Mo)-containing film.

[0002] In recent years, with the advancement of miniaturization of devices and the development of multilayer wiring structures, there has been a demand for more precise planarization of substrate surfaces at each stage of semiconductor substrate manufacturing. To address this demand, a new technology called chemical mechanical polishing (CMP) has been introduced. This involves pressing a wafer against an abrasive cloth called a buff while supplying a slurry mixture of abrasive particles and chemicals, and then rotating the buff to combine chemical and physical actions to polish and planarize insulating films and metal materials.

[0003] Chemical mechanical polishing (CMP) is performed using a slurry containing abrasive particles made of silicon compounds such as alumina and silicon oxide, or cerium compounds such as cerium oxide. After chemical mechanical polishing (CMP), the substrate surface is contaminated by particles, typically alumina, silica, or cerium oxide particles, contained in the slurry, as well as metal impurities derived from the constituent materials of the surface being polished and the chemicals contained in the slurry. These post-CMP residues can cause pattern defects, poor adhesion, and poor electrical properties, and therefore must be completely removed before the next process.

[0004] Conventionally, tungsten (W) has been used for contact plugs that raise electrodes such as the gate, source, and drain of transistors above the insulating film, but as wiring becomes finer, problems such as increased wiring resistance and wiring defects due to electromigration (EM) have emerged. For advanced devices, molybdenum (Mo), which has a high melting point, high EM resistance, and low resistance, is being considered as an alternative material to tungsten (W).

[0005] When a chemical mechanical polishing (CMP) process is performed after embedding molybdenum (Mo) wiring, post-CMP residues, such as abrasive particles from the slurry and organic residues containing molybdenum (Mo), remain on the wafer surface. Because these post-CMP residues, such as remaining abrasive particles, can cause wiring defects, they are removed in a post-CMP (p-CMP) cleaning process. Furthermore, the surface after cleaning must be highly clean, and deformation due to corrosion of the molybdenum (Mo) wiring must be minimized.

[0006] Patent Document 1 discloses a cleaning liquid composition used for treating a molybdenum-containing substrate, which contains an organic acid and two or more organic amine compounds.

[0007] International Publication No. WO2023 / 189432A1

[0008] The present inventors have conducted research aimed at providing a cleaning solution composition for substrates having the above-mentioned molybdenum (Mo)-containing film, which efficiently ensures good cleaning properties for post-CMP residues such as abrasive particles derived from the slurry and organic residues containing molybdenum (Mo), while suppressing deformation due to corrosion of the molybdenum (Mo) wiring as much as possible. That is, an object of the present invention is to provide a cleaning solution composition that efficiently exhibits good cleaning properties for post-CMP residues such as abrasive particles derived from the slurry and organic residues containing molybdenum (Mo), on substrates having a molybdenum (Mo)-containing film, and suppresses deformation due to corrosion of the molybdenum (Mo) wiring as much as possible.

[0009] In the course of intensive research to solve the above problems, the present inventors have found that a cleaning liquid composition containing one or more reducing agents and water and having a pH of 7 or less exhibits good cleaning properties for post-CMP residues such as abrasive grains derived from a slurry and organic residues containing molybdenum (Mo), and is also capable of inhibiting corrosion of molybdenum (Mo) and maintaining high flatness of the molybdenum (Mo) surface. As a result of further research, the present inventors have completed the present invention.

[0010] That is, the present invention relates to the following: [1] A cleaning liquid composition for cleaning a substrate having a molybdenum (Mo)-containing film, the cleaning liquid composition comprising one or more reducing agents and water, and having a pH of 7 or less. [2] The cleaning liquid composition according to [1] above, wherein the reducing agent is selected from the group consisting of hydroxylamine derivatives, gallic acid, ascorbic acid, and pyrogallol. [3] The cleaning liquid composition according to [2] above, wherein the hydroxylamine derivative is selected from the group consisting of N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine.

[0011] [4] The cleaning liquid composition according to any one of [1] to [3] above, further comprising one or more pH adjusters. [5] The cleaning liquid composition according to [4] above, wherein the pH adjuster is a quaternary ammonium compound or an inorganic acid. [6] The cleaning liquid composition according to [5] above, wherein the quaternary ammonium compound is trimethyl-2-hydroxyethylammonium hydroxide. [7] The cleaning liquid composition according to [5] above, wherein the inorganic acid is selected from the group consisting of nitric acid, sulfuric acid, hydrofluoric acid, and hydrochloric acid.

[0012] [8] The cleaning liquid composition according to any one of [1] to [7], further comprising one or more surfactants. [9] The cleaning liquid composition according to [8], wherein the surfactant is a polysulfonic acid compound.

[0013]

[10] The cleaning liquid composition according to any one of [1] to [9] above, further comprising one or more anticorrosive agents.

[11] The cleaning liquid composition according to

[10] above, wherein the anticorrosive agent is a nitrogen-containing ring compound or a thiol compound.

[12] The cleaning liquid composition according to

[11] above, wherein the nitrogen-containing ring compound is selected from the group consisting of 1,2,4-triazole, 3-mercapto-1,2,4-triazole, and bismuthiol.

[13] The cleaning liquid composition according to

[11] above, wherein the thiol compound is cysteine ​​or thiosalicylic acid.

[0014]

[14] A stock solution composition for the cleaning liquid composition according to any one of [1] to

[13] above, which is used to obtain the cleaning liquid composition by diluting it 10 to 1000 times.

[15] A method for cleaning a substrate having a molybdenum (Mo)-containing film, comprising a step of contacting the cleaning liquid composition according to any one of [1] to

[13] above with the substrate having a molybdenum (Mo)-containing film.

[0015]

[16] A method for producing a semiconductor substrate, comprising a step of contacting a substrate having a molybdenum (Mo)-containing film with the cleaning liquid composition according to any one of [1] to

[13] above.

[17] A method for producing a semiconductor substrate according to

[16] above, comprising a step of chemically mechanically polishing (CMP) the substrate having a molybdenum (Mo)-containing film before the step of contacting the substrate having a molybdenum (Mo)-containing film.

[18] A method for producing a semiconductor substrate according to

[16] or

[17] above, wherein the step of contacting the substrate having a molybdenum (Mo)-containing film is a step of cleaning the substrate having a molybdenum (Mo)-containing film.

[0016] The cleaning solution composition of the present invention can effectively remove metal impurities and fine particles, particularly abrasive grains derived from the slurry, and post-CMP residues such as organic residues containing molybdenum (Mo), in a short time when cleaning the surface of metal materials such as molybdenum (Mo) on substrates that have been subjected to polishing, etching, chemical mechanical polishing (CMP), or the like in the manufacturing process of electronic devices such as semiconductor elements. It also inhibits corrosion of metals such as molybdenum (Mo) and maintains high flatness of the metal surface. Furthermore, when the reducing agent is a hydroxylamine derivative, the cleaning solution composition of the present invention exhibits high pH stability over time. The cleaning solution composition of the present invention can further contain a surfactant, thereby more effectively removing post-CMP residues. The cleaning solution composition of the present invention can also further contain a corrosion inhibitor, thereby more effectively inhibiting corrosion of metal materials such as molybdenum (Mo) on substrates having a molybdenum (Mo)-containing film.

[0017] Fig. 1 is a diagram showing the cleaning performance of post-CMP residues on Mo-containing substrates and the solubility of Mo for the cleaning liquid compositions of Comparative Example 3 and Example 5. Fig. 2 is a diagram showing the pH and Mo solubility for the cleaning liquid compositions of Example 7 and Comparative Examples 4 and 5. Fig. 3 is a diagram showing the cleaning performance of post-CMP residues on Mo-containing substrates and the solubility of Mo for the cleaning liquid compositions of Examples 5 to 8.

[0018] The present invention will be described in detail below based on preferred embodiments of the present invention.

[0019] The present invention relates to a cleaning liquid composition for cleaning a substrate having a molybdenum (Mo)-containing film, the cleaning liquid composition comprising one or more reducing agents and water, and having a pH of 7 or less.

[0020] The reducing agent used in the present invention is not particularly limited, but examples thereof include hydroxylamine derivatives, gallic acid, ascorbic acid, and pyrogallol.

[0021] Hydroxylamine derivatives include hydroxylamine (NH ２ Hydroxylamine derivatives are compounds in which one or two hydrogen atoms (H) bonded to nitrogen atoms (N) in the hydroxylamine (NH OH) are substituted with alkyl groups, preferably alkyl groups having 1 to 2 carbon atoms. ２ Hydroxylamine derivatives are more stable than hydroxylamine derivatives (OH). Hydroxylamine derivatives have the property of increasing reactivity through the formation of a complex with a metal (ion). In other words, in a cleaning solution composition for molybdenum (Mo), the reactivity is selectively increased at the interface between molybdenum (Mo) and the cleaning solution composition, resulting in reduction. Therefore, the cleaning solution composition of the present invention containing the hydroxylamine derivative maintains high stability while exhibiting excellent reduction at the interface between molybdenum (Mo) and the cleaning solution composition during use, thereby achieving effective cleaning. Examples of hydroxylamine derivatives include N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine, with N,N-diethylhydroxylamine being preferred.

[0022] In one embodiment, the reducing agent is selected from the group consisting of hydroxylamine derivatives, gallic acid, ascorbic acid, and pyrogallol. From the viewpoint of pH stability, the reducing agent is preferably a hydroxylamine derivative. One or more reducing agents can be used. The concentration of the reducing agent in the cleaning solution composition is not limited thereto, but is preferably 0.1 mM to 100 mM, and particularly preferably 1 mM to 10 mM. In one embodiment, the cleaning solution composition of the present invention does not contain gallic acid.

[0023] The cleaning liquid composition of the present invention contains water in an amount of 50 wt % or more, preferably 90 wt % or more, based on the cleaning liquid composition.

[0024] The hydrogen ion concentration (pH) of the cleaning liquid composition of the present invention is 7 or less.

[0025] In one embodiment, the cleaning liquid composition of the present invention may contain a pH adjuster. The pH adjuster is not particularly limited as long as it can adjust the pH to a predetermined level, and examples thereof include quaternary ammonium compounds, inorganic acids, potassium hydroxide, sodium hydroxide, and aqueous ammonium solutions, with quaternary ammonium compounds and inorganic acids being preferred.

[0026] Examples of quaternary ammonium compounds include, but are not limited to, tetramethylammonium hydroxide (TMAH), trimethyl-2-hydroxyethylammonium hydroxide (choline hydroxide), tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, trimethylphenylammonium hydroxide, benzyltrimethylammonium hydroxide, dimethylbis(2-hydroxyethyl)ammonium hydroxide, and methyltris(2-hydroxyethyl)ammonium hydroxide. Preferred are trimethyl-2-hydroxyethylammonium hydroxide (choline hydroxide), tetraethylammonium hydroxide, dimethylbis(2-hydroxyethyl)ammonium hydroxide, and methyltris(2-hydroxyethyl)ammonium hydroxide. Particularly preferred is trimethyl-2-hydroxyethylammonium hydroxide (choline hydroxide).

[0027] Examples of inorganic acids include, but are not limited to, nitric acid, sulfuric acid, hydrofluoric acid, hydrochloric acid, phosphoric acid, etc., and are preferably selected from the group consisting of nitric acid, sulfuric acid, hydrofluoric acid, and hydrochloric acid, with nitric acid being particularly preferred.

[0028] The cleaning liquid composition of the present invention preferably does not contain tetramethylammonium hydroxide (TMAH), which is a quaternary ammonium compound, from the viewpoint of suppressing toxicity to the human body.

[0029] In one embodiment, the cleaning liquid composition of the present invention may contain a surfactant. By including a surfactant, the cleaning liquid composition of the present invention can more effectively remove post-CMP residues, such as abrasive grains derived from the slurry and organic residues containing molybdenum (Mo), from a substrate having a molybdenum (Mo)-containing film. The surfactant is appropriately selected depending on the fine particles and substrate to be removed, and is not particularly limited. Examples of the surfactant include polysulfonic acid compounds, polycarboxylic acid compounds, and polyphosphonic acid compounds, and preferably polysulfonic acid compounds.

[0030] Examples of polysulfonic acid compounds include naphthalenesulfonic acid formaldehyde condensates, polystyrenesulfonic acid, ligninsulfonic acid, and salts thereof, with naphthalenesulfonic acid formaldehyde condensates being preferred. One or more surfactants may be used. The concentration of the surfactant in the cleaning liquid composition is not limited thereto, but is preferably 1 ppm to 10,000 ppm, and particularly preferably 1 ppm to 100 ppm.

[0031] In one embodiment, the cleaning liquid composition of the present invention may contain a corrosion inhibitor. By containing the corrosion inhibitor, the cleaning liquid composition of the present invention can further suppress corrosion of metal materials such as molybdenum (Mo) on a substrate having a molybdenum (Mo)-containing film. Examples of the corrosion inhibitor include, but are not limited to, nitrogen-containing ring compounds, thiol compounds, and sulfur-containing ring compounds, and nitrogen-containing ring compounds and thiol compounds are preferred.

[0032] Examples of the nitrogen-containing ring compound include, but are not limited to, pyrrole, pyrazoline, pyrazole, imidazole, triazole, imidazoline, oxazoline, oxazole, isoxazole, and derivatives thereof. Specific examples include 1H-pyrrole, 1-pyrroline, 2-pyrroline, 3-pyrroline, pyrrolidine, pyrrolidone, γ-butyrolactam, γ-valerolactam, proline, prolyl, hygric acid, hygroyl, minalin, 1H-pyrazole, 1-pyrazoline, 2-pyrazoline, pyrazolidine, pyrarizolidone, 3-pyrazolone, 4-pyrazolone, 5-pyrazolone, 1H-pyrazole-4-carboxylic acid, 1-methyl-1H-pyrazole-5-carboxylic acid, 5-methyl-1H-pyrazole-3-carboxylic acid, 3, Examples of the anti-inflammatory agent include 5-pyrazoledicarboxylic acid, 3-amino-5-hydroxypyrazole, 1H-imidazole, 2-imidazoline, 3-imidazoline, 4-imidazoline, imidazolidine, imidazolidone, 1,3,4-thiadiazole, 5-mercapto-1,3,4-thiadiazole, 2-amino-5-mercapto-1,3,4-thiadiazole, bismuthiol, ethyleneurea, hydantoin, allantoin, histidine, histidyl, histamine, 1,2,3-triazole, 1,2,4-triazole, 1-hydroxybenzotriazole, 3-amino-1,2,4-triazole, 3-mercapto-1,2,4-triazole, 4-ano-1,2,4-triazole, and 3,5-diamino-1,2,4-triazole. As the nitrogen-containing ring compound, from the viewpoints of industrial availability and high water solubility, preferred are pyrazole, 3,5-pyrazoledicarboxylic acid, 3-amino-5-hydroxypyrazole, imidazole, triazole, 3-mercapto-1,2,4-triazole, 3,5-diamino-1,2,4-triazole, histidine, and histamine, and particularly preferred are 1,2,4-triazole, 3-mercapto-1,2,4-triazole, 5-mercapto-1,3,4-thiadiazole, and bismuthiol.

[0033] Examples of thiol compounds include, but are not limited to, methanethiol, 2-aminoethanethiol, 2-mercaptoethanol, 1-thioglycerol, thioglycolic acid, 3-mercaptopropionic acid, allyl mercaptan, propanethiol, cyclopentanethiol, 2-methyl-1-butanethiol, 1,2-ethanedithiol, 1,3-propanedithiol, benzenethiol, 4-aminobenzenethiol, 2-hydroxybenzenethiol, thiosalicylic acid, 1,4-benzenedithiol, 2-mercaptopyridine, 2-mercaptopyrimidine, 2-mercaptopyrazine, 3-furanthiol, 2-mercaptoimidazole, 2-thiophenethiol, cyclohexanethiol, 2-mercaptothiazole, 2-mercaptothiazoline, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, cysteine, homocysteine, and N-acetylcysteine. Particularly preferred are cysteine ​​and thiosalicylic acid. Examples of sulfur-containing ring compounds include, but are not limited to, thiophene, 2-methylthiophene, 3-methylthiophene, 3-fluorothiophene, 2-aminomethylthiophene, 2-thiophenemethanol, 3-thiophenemethanol, 2-thiophenecarboxylic acid, and 3-thiophenecarboxylic acid.

[0034] The concentration of the anticorrosive agent in the cleaning liquid composition is not limited to this, but is preferably 0.01 mM to 100 mM, and particularly preferably 0.1 mM to 10 mM.

[0035] In one embodiment, the cleaning liquid composition of the present invention does not contain a combination of gallic acid and cysteine.

[0036] The substrate having a molybdenum (Mo)-containing film in the present invention is not limited to a substrate obtained after chemical mechanical polishing (CMP), but examples thereof include a substrate immediately after CMP, a substrate immediately after processing an upper insulating film by dry etching after forming a molybdenum (Mo)-containing film such as a molybdenum (Mo) contact plug and / or a molybdenum (Mo) wiring, etc. Among these, a substrate immediately after chemical mechanical polishing (CMP) is preferred.

[0037] The chemical mechanical polishing (CMP) in the present invention can be carried out in accordance with known chemical mechanical polishing methods, and is not limited thereto, for example, silicon oxide (SiO ２ ) and alumina (Al ２ O ３ ), and abrasive-less polishing method using electrolytic water. Among these, silicon oxide (SiO ２ ) and alumina (Al ２ O ３ This is a polishing method that uses abrasive grains such as

[0038] The cleaning liquid composition of the present invention can be obtained by diluting the concentrate composition of the present invention. The cleaning liquid composition of the present invention can be obtained by diluting the concentrate composition, for example, but not limited to, 10 times or more, preferably 10 to 1000 times, more preferably 50 to 200 times, and the dilution amount is appropriately determined depending on the composition of the concentrate composition.

[0039] Since the cleaning liquid composition of the present invention is mostly composed of water, when a dilution and mixing apparatus is installed in the production line of electronic devices, the cleaning liquid composition of the present invention can be supplied as an undiluted liquid composition and diluted with a diluting liquid containing water (including a diluting liquid consisting only of ultrapure water) immediately before use. This has the advantage of contributing to reduced transportation costs, reduced carbon dioxide gas emissions during transportation, and reduced production costs for electronic device manufacturers.

[0040] The cleaning liquid composition of the present invention is suitable for use on a substrate having a molybdenum (Mo)-containing film, and is particularly suitable for use on a substrate having a molybdenum (Mo) contact plug and / or molybdenum (Mo) wiring. In one embodiment, the cleaning liquid composition of the present invention may be used on a substrate not containing copper (Cu). The cleaning liquid composition of the present invention is also suitable for use on a substrate after chemical mechanical polishing (CMP), where the substrate surface after chemical mechanical polishing (CMP) contains various wirings on the substrate surface, as well as barrier metal materials (CoTi-based compounds, Ta-based compounds, Ru, etc.) and insulating film materials (SiO ２ In addition to the fine particles (particles such as alumina, silica, and cerium oxide), the slurry may contain fine particles and metal impurities. The fine particles are, for example, mainly alumina, silica, and cerium oxide, and the metal impurities include copper (Cu) that dissolves in the slurry during polishing and re-adheres, iron (Fe) derived from the oxidizing agent in the slurry, and molybdenum (Mo) organometallic complexes formed by a reaction between molybdenum (Mo) and a molybdenum (Mo) corrosion inhibitor contained in the slurry.

[0041] In the present invention, the barrier metal refers to a layer (barrier metal layer) formed between a contact plug or wiring of a semiconductor substrate and an insulating film in order to prevent the metal in the contact plug or wiring from diffusing into the insulating film, and includes cobalt (Co), titanium (Ti)-based compounds, tantalum (Ta)-based compounds, ruthenium (Ru), and the like.

[0042] Low-k materials are materials with a low dielectric constant that are used in interlayer insulating films, etc., and include, but are not limited to, porous silicon, silicon-containing organic polymers, TEOS (tetraethoxysilane), etc. Specific examples include Black Diamond (manufactured by Applied Materials, Inc.) and Aurora (manufactured by ASM International).

[0043] The present invention also relates to a method for cleaning a substrate having a molybdenum (Mo)-containing film, which comprises the step of contacting the substrate having the molybdenum (Mo)-containing film with the cleaning liquid composition of the present invention.

[0044] The present invention still further relates to a method for producing a semiconductor substrate, which comprises a step of contacting a substrate having a molybdenum (Mo)-containing film with the cleaning liquid composition of the present invention. In one embodiment, the method for producing a semiconductor substrate comprises a step of chemical mechanical polishing (CMP) the substrate having a molybdenum (Mo)-containing film before the step of contacting the substrate having the molybdenum (Mo)-containing film with the cleaning liquid composition of the present invention.

[0045] Examples of contacting steps include, but are not limited to, a cleaning step after chemical mechanical polishing (CMP) and a cleaning step after processing an insulating film on a molybdenum (Mo) contact plug by dry etching. Examples of contacting methods include, but are not limited to, a single-wafer cleaning method that also uses brush scrubbing, a single-wafer cleaning method in which a cleaning solution is sprayed from a spray or nozzle, a batch spray cleaning method, and a batch immersion cleaning method. Among these, preferred are the single-wafer cleaning method that also uses brush scrubbing and the single-wafer cleaning method in which a cleaning solution is sprayed from a spray or nozzle, and particularly preferred is the single-wafer cleaning method that also uses brush scrubbing.

[0046] The atmosphere in which the contact is performed includes, but is not limited to, air, a nitrogen atmosphere, and a vacuum. Of these, air and a nitrogen atmosphere are preferred. The contact time is appropriately selected depending on the purpose and is not particularly limited. For single-wafer cleaning methods that use brush scrubbing in combination and single-wafer cleaning methods in which a cleaning solution is sprayed from a spray or nozzle, it is 0.5 to 5 minutes, and for batch-type spray cleaning and batch-type immersion cleaning methods, it is 0.5 to 30 minutes. The temperature is appropriately selected depending on the purpose and is not particularly limited. For single-wafer cleaning methods that use brush scrubbing in combination and single-wafer cleaning methods in which a cleaning solution is sprayed from a spray or nozzle, it is 20°C to 50°C, and for batch-type spray cleaning and batch-type immersion cleaning methods, it is 20°C to 100°C. The above-mentioned contact conditions can be combined appropriately depending on the purpose.

[0047] Examples of semiconductor substrates include, but are not limited to, silicon, silicon carbide, silicon nitride, gallium arsenide, gallium nitride, gallium phosphide, indium phosphide, etc. Among these, silicon, silicon carbide, gallium arsenide, and gallium nitride are preferred, and silicon and silicon carbide are particularly preferred.

[0048] Next, the cleaning liquid composition of the present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these.

[0049] 1. Preparation of Cleaning Liquid Compositions First, cleaning liquid compositions according to Examples 1 to 15 and Comparative Examples 1 to 5 were prepared. Specifically, as shown in Table 1, a reducing agent, a surfactant, an anticorrosive agent, and / or a pH adjuster were added to water and mixed to prepare the cleaning liquid compositions according to Examples 1 to 15 and Comparative Examples 1 to 5.

[0050] 2. Evaluation of cleaning ability of cleaning liquid composition for molybdenum (Mo) substrate 2.1. Preparation of CMP polishing liquid Hydrogen peroxide was added to a slurry using silicon oxide (W2000-V WIN, manufactured by Cabot) so that the concentration became 4.5 wt %, to obtain a CMP polishing liquid.

[0051] 2.2 Preparation of substrate to be polished A molybdenum (Mo) substrate with the following configuration was prepared (ALD-Mo 30 nm / Si, manufactured by Global Net Co., Ltd.) The molybdenum (Mo) substrate was chipped to 2.0 cm x 2.0 cm to obtain molybdenum (Mo) chips to be polished.

[0052] 2.3. Polishing and Cleaning of Molybdenum (Mo) Chips Using the above CMP polishing solution, the above molybdenum (Mo) chips to be polished were polished for 30 seconds using a polishing machine (manufactured by MAT Corporation, model number BC-15CN). After polishing, the wafer was rinsed for 10 seconds with ultrapure water (DIW) while rotating. The chips were immersed in 100 mL of each of the cleaning liquid compositions listed in Table 1, stirred at 200 rpm, and cleaned for 1 minute. The molybdenum (Mo) chips after cleaning were then rinsed with N ２ After drying by blowing, a molybdenum (Mo) chip for measurement was obtained.

[0053] 2.4. Measurement of the number of defects on the molybdenum (Mo) chip surface The number of defects on the molybdenum (Mo) chip surface for the above measurement was determined by observing the molybdenum (Mo) chip surface at 10,000x magnification using an FE-SEM (Reegulus) and counting the number of deposits observed within an area of ​​12.7 μm × 9.5 μm. The post-CMP residue removal rate was calculated using the following formula. The post-CMP residue removal rate for each cleaning composition is shown in Table 1 and Figures 1 and 3.

[0054] 3. Evaluation of Corrosivity of Cleaning Liquid Compositions to Molybdenum (Mo) 3.1. Preparation of Molybdenum (Mo) Chips A molybdenum (Mo) substrate with the following configuration was prepared (PMD-Mo 500 nm / Si, manufactured by Advanced Materials Technology Co., Ltd.). The molybdenum (Mo) substrate was chipped to 1.5 cm x 1.5 cm to obtain molybdenum (Mo) chips for evaluation. 3.2. Preparation of Evaluation Solution The molybdenum (Mo) chips for evaluation were immersed in a 1.0 mM aqueous solution of tetramethylhydroxyammonium hydroxide (TMAH) for 2 minutes and then rinsed with running ultrapure water (DIW). They were then immersed in 50 mL of each cleaning composition listed in Table 1 for 1 minute while stirring at 200 rpm. The molybdenum (Mo) chips were removed, and the cleaning compositions after immersion were used as evaluation solutions. 3.3. Measurement of Etching Rate The molybdenum (Mo) concentration in the evaluation solution was measured using an ICP-MS (Agilent, model number: 7900). The etching rate (ER) of molybdenum (Mo) was calculated from the obtained molybdenum (Mo) concentration using the following formula. The evaluation results are shown in Table 1 and Figures 1 to 3.

[0055] 4. result In Table 1, DEHA is N,N-diethylhydroxylamine, surfactant is naphthalenesulfonic acid formaldehyde condensate, and mTAZ is 3-mercapto-1,2,4-triazole.

[0056] The cleaning solution composition of Example 5, which contained a reducing agent, exhibited a post-CMP residue removal rate of 81% or more, while the cleaning solution composition of Comparative Example 3, which did not contain a reducing agent, exhibited a post-CMP residue removal rate of only 53% or less (Figure 1), demonstrating that a reducing agent is effective for improving cleaning performance. Furthermore, the cleaning solution compositions of Comparative Examples 4 and 5, despite containing the same components as the cleaning solution composition of Example 7, exhibited higher molybdenum (Mo) E.R. (Figure 2), indicating that molybdenum (Mo) corrosion cannot be suppressed at alkaline pH levels. Furthermore, the cleaning solution compositions of Examples 7 and 8 exhibited even improved post-CMP residue removal rates compared to the cleaning solution compositions of Examples 5 and 6 (Figure 3), demonstrating that a surfactant is effective for improving cleaning performance.

Claims

1. A cleaning composition for cleaning a substrate having a molybdenum (Mo)-containing film, the cleaning composition comprising one or more reducing agents and water, and having a pH of 7 or less.

2. The cleaning solution composition of claim 1, wherein the reducing agent is selected from the group consisting of hydroxylamine derivatives, gallic acid, ascorbic acid, and pyrogallol.

3. The cleaning liquid composition according to claim 2, wherein the hydroxylamine derivative is selected from the group consisting of N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine.

4. The cleaning liquid composition of claim 1, further comprising one or more pH adjusters.

5. The cleaning liquid composition according to claim 4, wherein the pH adjuster is a quaternary ammonium compound or an inorganic acid.

6. The cleaning composition according to claim 5, wherein the quaternary ammonium compound is trimethyl-2-hydroxyethylammonium hydroxide.

7. The cleaning liquid composition according to claim 5, wherein the inorganic acid is selected from the group consisting of nitric acid, sulfuric acid, hydrofluoric acid and hydrochloric acid.

8. The cleaning composition of claim 1, further comprising one or more surfactants.

9. The cleaning liquid composition according to claim 8, wherein the surfactant is a polysulfonic acid compound.

10. The cleaning solution composition of claim 1, further comprising one or more corrosion inhibitors.

11. The cleaning liquid composition according to claim 10, wherein the corrosion inhibitor is a nitrogen-containing ring compound or a thiol compound.

12. The cleaning composition according to claim 11, wherein the nitrogen-containing ring compound is selected from the group consisting of 1,2,4-triazole, 3-mercapto-1,2,4-triazole, and bismuthiol.

13. The cleaning liquid composition according to claim 11, wherein the thiol compound is cysteine ​​or thiosalicylic acid.

14. A concentrate composition for a cleaning liquid composition according to claim 1, which is used to obtain the cleaning liquid composition by diluting it 10 to 1000 times.

15. A method for cleaning a substrate having a molybdenum (Mo)-containing film, comprising the step of contacting the substrate having a molybdenum (Mo)-containing film with the cleaning liquid composition of claim 1.

16. A method for producing a semiconductor substrate, comprising the step of contacting the cleaning liquid composition of claim 1 with a substrate having a molybdenum (Mo)-containing film.

17. The method for producing a semiconductor substrate according to claim 16, further comprising chemically mechanically polishing (CMP) the substrate having the molybdenum (Mo)-containing film prior to the step of contacting the substrate having the molybdenum (Mo)-containing film.

18. The method for producing a semiconductor substrate according to claim 16, wherein the step of contacting the substrate having the molybdenum (Mo)-containing film is a step of cleaning the substrate having the molybdenum (Mo)-containing film.

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