Cleaning solution composition

Abstract

To provide a cleaning solution composition that effectively cleans post-CMP residues, such as abrasive particles derived from the slurry and organic residues containing molybdenum (Mo), from both a molybdenum (Mo)-containing film and an insulating film on a substrate having the molybdenum (Mo)-containing film and the insulating film.SOLUTION: A cleaning solution composition for cleaning substrates having a molybdenum (Mo)-containing film and an insulating film contains one or more reducing agents, two or more surfactants, and water, at least one surfactant is a polycarboxylic acid compound, and its pH is equal to or less than 7.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[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 abrasives 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 becomes contaminated by particles, typically alumina, silica, or cerium oxide particles, contained in the slurry, as well as metal impurities 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, so they must be completely removed before the next process.

[0004] Traditionally, 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, issues 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 and therefore high EM resistance, and low resistance, is being considered as a material to replace tungsten (W).

[0005] When the 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 the 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. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. WO2023 / 189432A1 Summary of the Invention [Problem to be solved by the invention]

[0008] In one embodiment, a substrate using molybdenum (Mo) wiring is manufactured by the following procedure: (1) forming a transistor on a substrate; (2) forming an insulating film on the transistor; (3) dry-etching the insulating film down to each electrode of the transistor to form contact holes; (4) forming a molybdenum (Mo) film by a chemical vapor deposition (CVD) method or the like; and (5) polishing away the excess portion of the molybdenum (Mo) film to the height of the insulating film by chemical mechanical polishing (CMP). The present inventors have found that in the chemical mechanical polishing (CMP) step (5), post-CMP residues such as abrasive particles derived from the slurry and organic residues containing molybdenum (Mo) remain on the surface of a substrate having a molybdenum (Mo)-containing film and an insulating film, and that when such a substrate is washed, the cleaning properties differ between the molybdenum (Mo)-containing film and the insulating film. The present inventors have conducted research with the objective of providing a cleaning solution composition that effectively removes post-CMP residues, such as abrasive particles derived from a slurry and organic residues containing molybdenum (Mo), not only from molybdenum (Mo)-containing films but also from insulating films. That is, the objective of the present invention is to provide a cleaning solution composition that effectively removes post-CMP residues, such as abrasive particles derived from a slurry and organic residues containing molybdenum (Mo), from both a molybdenum (Mo)-containing film and an insulating film on a substrate having the film and the insulating film (Figure 1). [Means for solving the problem]

[0009] In the course of intensive research to solve the above problems, the present inventors discovered that a cleaning liquid composition containing one or more reducing agents, two or more surfactants, and water, wherein at least one of the surfactants is a polycarboxylic acid compound and has a pH of 7 or less, can effectively remove post-CMP residues, such as slurry-derived abrasive particles and organic residues containing molybdenum (Mo), from both molybdenum (Mo)-containing films and insulating films. 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 and an insulating film, the cleaning liquid composition comprising one or more reducing agents, two or more surfactants, and water, wherein at least one of the surfactants is a polycarboxylic acid compound, and the cleaning liquid composition has a pH of 7 or less. [2] The cleaning liquid composition according to [1] above, wherein the polycarboxylic acid compound is a polyacrylic acid compound. [3] The cleaning liquid composition according to [1] or [2], wherein at least one of the surfactants is a polysulfonic acid compound.

[0011] [4] The cleaning liquid composition according to any one of the above [1] to [3], wherein the reducing agent is selected from the group consisting of hydroxylamine derivatives, gallic acid, ascorbic acid, and pyrogallol. [5] The cleaning liquid composition according to [4], wherein the hydroxylamine derivative is selected from the group consisting of N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine. [6] The cleaning liquid composition according to any one of the above [1] to [5], further comprising one or more pH adjusters.

[0012] [7] The cleaning liquid composition according to [6] above, wherein the pH adjuster is a quaternary ammonium compound or an inorganic acid. [8] The cleaning liquid composition according to [7] above, wherein the quaternary ammonium compound is trimethyl-2-hydroxyethylammonium hydroxide. [9] The cleaning liquid composition according to [7] above, wherein the inorganic acid is selected from the group consisting of nitric acid, sulfuric acid, hydrofluoric acid, and hydrochloric acid.

[0013]

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

[11] The cleaning liquid composition according to

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

[12] The cleaning liquid composition according to

[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

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

[0014]

[14] The cleaning liquid composition according to any one of the above [1] to

[13] , wherein the insulating film is a tetraethoxysilane (TEOS) film or a silicon nitride (SiN) film.

[15] A concentrate composition for a cleaning liquid composition according to any one of [1] to

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

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

[14] .

[0015]

[17] A method for producing a semiconductor substrate, comprising a step of contacting the cleaning liquid composition according to any one of [1] to

[14] above with a substrate having a molybdenum (Mo)-containing film and an insulating film.

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

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

[19] The method for producing a semiconductor substrate according to

[17] or

[18] , wherein the step of contacting the substrate having the molybdenum (Mo)-containing film and the insulating film is a step of cleaning the substrate having the molybdenum (Mo)-containing film and the insulating film. [Effects of the Invention]

[0016] The cleaning liquid composition of the present invention can effectively and quickly remove metal impurities and fine particles, particularly abrasive grains derived from the slurry, and post-CMP residues such as organic residues containing molybdenum (Mo), when cleaning metal materials such as molybdenum (Mo) and insulating film surfaces on substrates that have been subjected to polishing, etching, chemical mechanical polishing (CMP), etc. in the manufacturing process of electronic devices such as semiconductor elements. The cleaning solution compositions of the present invention also exhibit high pH stability over time when the reducing agent is a hydroxylamine derivative. The cleaning liquid composition of the present invention further contains an anticorrosive agent, thereby making it possible to inhibit corrosion of metal materials such as molybdenum (Mo) on a substrate having a molybdenum (Mo)-containing film and an insulating film. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 shows a substrate having an Mo-containing film and an insulating film before and after cleaning. [Figure 2] FIG. 2 is a graph showing the cleaning performance of the cleaning liquid compositions of Comparative Examples 1 to 3 and Example 1 for removing post-CMP residue on a Mo chip, and the solubility of Mo. [Figure 3] FIG. 1 is a graph showing the cleaning properties of the cleaning liquid compositions of Comparative Example 3 and Example 1 for removing post-CMP residues on a substrate having a TEOS film or a substrate having a silicon nitride film. DETAILED DESCRIPTION OF THE INVENTION

[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 and an insulating film, the cleaning liquid composition comprising one or more reducing agents, two or more surfactants, and water, wherein at least one of the surfactants is a polycarboxylic acid compound, and the cleaning liquid composition has 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] A hydroxylamine derivative is a compound in which one or two hydrogens (H) bonded to nitrogen (N) in hydroxylamine (NHOH) are substituted with alkyl groups, preferably alkyl groups having 1 to 2 carbon atoms. Hydroxylamine derivatives are more stable than unsubstituted hydroxylamine (NHOH). Hydroxylamine derivatives also have the property of increasing reactivity by forming a complex with a metal (ion). In other words, in a cleaning liquid composition intended for molybdenum (Mo), the reactivity is selectively increased at the interface between molybdenum (Mo) and the cleaning liquid composition, demonstrating reducing properties. Therefore, the cleaning liquid composition of the present invention containing the above-mentioned hydroxylamine derivative maintains high stability and exhibits excellent reducing properties at the molybdenum (Mo) / cleaning liquid composition interface during use, thereby achieving a cleaning effect. Examples of hydroxylamine derivatives include N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine, with N,N-diethylhydroxylamine being preferred.

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

[0023] The cleaning liquid composition of the present invention contains two or more surfactants. The cleaning liquid composition of the present invention contains two or more surfactants, and thus can effectively remove post-CMP residues, such as abrasive particles derived from the slurry and organic residues containing molybdenum (Mo), from a substrate having a molybdenum (Mo)-containing film and an insulating film.

[0024] At least one of the surfactants is a polycarboxylic acid compound. The cleaning liquid composition of the present invention, by containing a polycarboxylic acid compound, can more effectively remove post-CMP residues, such as abrasive particles derived from the slurry and organic residues containing molybdenum (Mo), particularly from substrates having insulating films. The polycarboxylic acid compound is not particularly limited as long as it is a polymer compound having a repeating unit having a carboxy group, and may also contain other acid groups such as a sulfo group, a hydroxy group, etc. Examples of the polycarboxylic acid compound include a polyacrylic acid compound, a polymaleic acid compound, a polymethacrylic acid compound, or a salt thereof, and from the viewpoint of removing post-CMP residues from a substrate having an insulating film, a polyacrylic acid compound or a salt thereof is preferred. The weight average molecular weight of the polycarboxylic acid compound is 1,000 to 10,000, and preferably 3,000 to 5,000. The polycarboxylic acid compound may contain one kind or two or more kinds. The concentration of the polycarboxylic acid compound in the cleaning liquid composition is not limited to this, but is preferably 1 ppm to 1000 ppm, and particularly preferably 50 ppm to 300 ppm.

[0025] The polyacrylic acid compound is not particularly limited as long as it is a polymer compound having a repeating unit having an acrylic acid group. It may be a polymer obtained by polymerizing a single monomer containing an acrylic acid group, or a copolymer obtained by polymerizing one or more monomers containing an acrylic acid group and one or more monomers containing an acid group other than an acrylic acid group. A polymer obtained by polymerizing a single monomer containing an acrylic acid group is polyacrylic acid. Examples of acid groups other than an acrylic acid group include methacrylic acid groups, sulfonic acid groups, and maleic acid groups. In the case of a copolymer obtained by polymerizing one or more monomers containing an acrylic acid group and one or more monomers containing an acid group other than an acrylic acid group, the molar ratio of the one or more monomers containing an acrylic acid group to the one or more monomers containing an acid group other than an acrylic acid group is not particularly limited, but may be, for example, 1:1 to 4:1. The polyacrylic acid compound is preferably polyacrylic acid.

[0026] The surfactant other than the polycarboxylic acid compound is appropriately selected depending on the fine particles and substrate to be removed, and is not particularly limited. Examples include polymer compounds having repeating units with groups selected from sulfonic acid groups, phosphonic acid groups, and sulfate ester groups, or salts thereof, and preferred are polysulfonic acid compounds, polyphosphonic acid compounds, polysulfuric acid ester compounds, and salts thereof. From the viewpoints of defoaming properties, environmental toxicity, and the like, polysulfonic acid compounds and salts thereof are particularly preferred. Examples of the polysulfonic acid compound include naphthalenesulfonic acid formaldehyde condensate, polystyrenesulfonic acid, ligninsulfonic acid, and salts thereof, with naphthalenesulfonic acid formaldehyde condensate being preferred. The concentration of the surfactant other than the polycarboxylic acid compound in the cleaning liquid composition is not limited to this, but is preferably 1 ppm to 1000 ppm, and particularly preferably 10 ppm to 100 ppm. The concentration of the two or more surfactants (including the polycarboxylic acid compound) in the cleaning liquid composition is not limited to this, but is preferably 2 ppm to 2000 ppm, and particularly preferably 60 ppm to 400 ppm.

[0027] The cleaning liquid composition of the present invention contains water, and the amount of water is 50 wt % or more, preferably 90 wt % or more, based on the cleaning liquid composition.

[0028] The hydrogen ion concentration (pH) of the cleaning liquid composition of the present invention is 7 or less.

[0029] 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. Examples of the pH adjuster include quaternary ammonium compounds, inorganic acids, potassium hydroxide, sodium hydroxide, and aqueous ammonium solutions, with quaternary ammonium compounds and inorganic acids being preferred.

[0030] 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).

[0031] 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.

[0032] One or more pH adjusters can be used. From the viewpoint of reducing toxicity to the human body, the cleaning liquid composition of the present invention preferably does not contain tetramethylammonium hydroxide (TMAH), which is a quaternary ammonium compound.

[0033] In one embodiment, the cleaning liquid composition of the present invention may contain a corrosion inhibitor. The cleaning liquid composition of the present invention contains an anticorrosive agent, which can inhibit corrosion of metal materials such as molybdenum (Mo) in a substrate having a molybdenum (Mo)-containing film and an insulating film. In particular, it is believed that the anticorrosive agent can inhibit even slight corrosion of molybdenum (Mo) that may be caused by a polycarboxylic acid compound, enabling the production of substrates with higher precision. The anticorrosive agent is not limited to these, but examples thereof include nitrogen-containing ring compounds, thiol compounds, and sulfur-containing ring compounds, and nitrogen-containing ring compounds and thiol compounds are preferred.

[0034] 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, and specific examples thereof 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, 3,5-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, ethylene urea, 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, 3,5-diamino-1,2,4-triazole, and the like. 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.

[0035] 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.

[0036] One or more types of anticorrosive agents can be used. 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.

[0037] In one embodiment, the cleaning liquid composition of the present invention does not contain a combination of gallic acid and cysteine.

[0038] The substrate having a molybdenum (Mo)-containing film and an insulating film in the present invention is not limited to a substrate obtained after chemical mechanical polishing (CMP), but is preferably a substrate immediately after CMP.

[0039] The chemical mechanical polishing (CMP) in the present invention can be performed in accordance with known chemical mechanical polishing methods, including, but not limited to, polishing methods using abrasive grains such as silicon oxide (SiO2) or alumina (Al2O3), and abrasive-less polishing methods using electrolytic water. Of these, polishing methods using abrasive grains such as silicon oxide (SiO2) or alumina (Al2O3) are preferred.

[0040] 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, but the dilution amount is appropriately determined depending on the composition.

[0041] Since the cleaning liquid composition of the present invention is mostly composed of water, when a dilution and mixing device is installed in the production line of electronic devices, the cleaning liquid composition 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.

[0042] The cleaning liquid composition of the present invention is suitable for use on substrates having molybdenum (Mo)-containing films and insulating films. Examples of molybdenum (Mo)-containing films include molybdenum (Mo) contact plugs, molybdenum (Mo) wiring, and molybdenum (Mo) vias. The cleaning liquid composition of the present invention is suitable for use on substrates having a molybdenum (Mo)-containing film, particularly a molybdenum (Mo) contact plug and / or a molybdenum (Mo) wiring.

[0043] Examples of insulating films include tetraethoxysilane (TEOS), silicon nitride (SiN), silicon oxide (SiO2), and low-k materials. Here, low-k materials are materials with low dielectric constants used for interlayer insulating films, etc., and include, but are not limited to, porous silicon, silicon-containing organic polymers, fluorine-doped silicon dioxide films (SiOF films), and carbon-doped silicon dioxide films. Specific examples include Black Diamond (manufactured by Applied Materials, Inc.) and Aurora (manufactured by ASM International). The cleaning solution composition of the present invention is particularly suitable for substrates having tetraethoxysilane (TEOS) or silicon nitride (SiN) as an insulating film. In one embodiment, the cleaning liquid composition of the present invention may be used on a substrate that does not contain copper (Cu).

[0044] The cleaning liquid composition of the present invention is also suitable for use on a substrate after chemical mechanical polishing (CMP). Here, the substrate surface after chemical mechanical polishing (CMP) may contain various wirings and barrier metal materials (CoTi-based compounds, Ta-based compounds, Ru, etc.) and insulating film materials (TEOS, SiN, SiO2, low-k) on the substrate surface, as well as fine particles and metal impurities contained in the slurry. The various wiring materials include one or more of molybdenum (Mo), cobalt (Co), copper (Cu), tungsten (W), and ruthenium (Ru).

[0045] Barrier metal materials include cobalt (Co), titanium (Ti)-based compounds, tantalum (Ta)-based compounds, ruthenium (Ru), etc., and are used in layers (barrier metal layers) formed between the insulating film and the contact plugs or wiring of a semiconductor substrate to prevent the metal in the contact plugs or wiring from diffusing into the insulating film.

[0046] The fine particles are mainly alumina, silica, and cerium oxide, for example, and the metal impurities include Mo (molybdenum) 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 when molybdenum (Mo) reacts with the molybdenum (Mo) corrosion inhibitor contained in the slurry.

[0047] The present invention also relates to a method for cleaning a substrate having a molybdenum (Mo)-containing film and an insulating film, which comprises the step of contacting the substrate having the molybdenum (Mo)-containing film and the insulating film with the cleaning liquid composition of the present invention.

[0048] 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 and an insulating film with the cleaning liquid composition of the present invention. In one embodiment, a method for producing a semiconductor substrate includes a step of chemically mechanically polishing (CMP) a substrate having a molybdenum (Mo)-containing film and an insulating film before a step of contacting the substrate having a molybdenum (Mo)-containing film and an insulating film with the cleaning liquid composition of the present invention.

[0049] Examples of contacting steps include, but are not limited to, a cleaning step after chemical mechanical polishing (CMP), preferably a cleaning step after chemical mechanical polishing (CMP) after forming contact holes by dry etching and depositing a molybdenum (Mo) film. Examples of contacting methods include, but are not limited to, single-wafer cleaning methods that combine brush scrubbing, single-wafer cleaning methods in which a cleaning solution is sprayed from a spray or nozzle, batch spray cleaning methods, and batch immersion cleaning methods. Of these, preferred are single-wafer cleaning methods that combine brush scrubbing and single-wafer cleaning methods in which a cleaning solution is sprayed from a spray or nozzle, and particularly preferred is single-wafer cleaning methods that combine brush scrubbing.

[0050] The atmosphere in which the contact is carried out is not limited to, but includes, for example, air, a nitrogen atmosphere, and a vacuum, among which air and a nitrogen atmosphere are preferred. The contact time is not particularly limited and is appropriately selected depending on the purpose, but is 0.5 to 5 minutes in the case of a single wafer cleaning method in which brush scrubbing is used in combination and a single wafer cleaning method in which a cleaning solution is sprayed from a spray or nozzle, and is 0.5 to 30 minutes in the case of a batch type spray cleaning method and a batch type immersion cleaning method. The temperature is not particularly limited and is appropriately selected depending on the purpose, but is 20°C to 50°C in the case of a single wafer cleaning method in which brush scrubbing is used in combination and a single wafer cleaning method in which a cleaning solution is sprayed from a spray or nozzle, and is 20°C to 100°C in the case of a batch type spray cleaning method and a batch type immersion cleaning method. The above-mentioned contact conditions can be combined appropriately depending on the purpose.

[0051] 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. [Example]

[0052] 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.

[0053] 1. Preparation of cleaning solution composition First, cleaning liquid compositions according to Example 1 and Comparative Examples 1 to 3 were prepared. Specifically, as shown in Table 1, a reducing agent, a surfactant (polysulfonic acid compound), a surfactant (polycarboxylic acid compound), an anticorrosive, a pH adjuster, and / or water (the balance) were added and mixed to prepare the cleaning liquid compositions according to Example 1 and Comparative Examples 1 to 3. [Table 1] In Table 1, DEHA is N,N-diethylhydroxylamine, the surfactant (polysulfonic acid compound) is naphthalenesulfonic acid formaldehyde condensate, mTAZ is 3-mercapto-1,2,4-triazole, and the surfactant (polycarboxylic acid compound) is polyacrylic acid (average molecular weight 5000, manufactured by Toa Gosei).

[0054] 2. Evaluation of cleaning ability of cleaning solution compositions for molybdenum (Mo) substrates 2.1. Preparation of CMP polishing solution Hydrogen peroxide was added to a slurry using silicon oxide (W2000-V WIN, manufactured by Cabot) to a concentration of 4.5 wt % to obtain a CMP polishing solution.

[0055] 2.2. Preparation of the substrate to be polished A molybdenum (Mo) substrate having the following configuration was prepared (ALD-Mo 30 nm / Si, manufactured by Global Net Co., Ltd.): The molybdenum (Mo) substrate was chipped to a size of 2.0 cm x 2.0 cm to obtain molybdenum (Mo) chips to be polished.

[0056] 2.3. Polishing and Cleaning Molybdenum (Mo) Chips The molybdenum (Mo) chips to be polished were polished for 30 seconds using the CMP polishing solution with a polishing machine (manufactured by MAT Corporation, model number BC-15CN). After polishing, the wafer was rinsed with ultrapure water (DIW) for 10 seconds while rotating. The chips were immersed in 100 mL of each cleaning solution composition listed in Table 1, stirred at 200 rpm, and washed for 1 minute. The molybdenum (Mo) chips after cleaning were dried with N2 blow to obtain molybdenum (Mo) chips for measurement.

[0057] 2.4. Measuring the number of defects on the surface of a molybdenum (Mo) chip The number of defects on the molybdenum (Mo) chip surface was measured by observing the surface of the molybdenum (Mo) chip at 10,000x magnification using a FE-SEM (Reegulus) and counting the number of deposits found within an area of ​​12.7 μm x 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 2 and Figure 2.

number

[0058] 3. Evaluation of the corrosiveness of cleaning solution compositions to molybdenum (Mo) 3.1. Preparation of Molybdenum (Mo) Chips A molybdenum (Mo) substrate having the following configuration was prepared (PMD-Mo 500 nm / Si, manufactured by Advanced Materials Technology Co., Ltd.): The molybdenum (Mo) substrate was chipped into 1.5 cm x 1.5 cm pieces 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 tetramethylhydroxyammonium hydroxide (TMAH) aqueous solution for 2 minutes, 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. Etching rate measurement 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 2 and Figure 2.

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[0059] 4. Evaluation of cleaning ability of cleaning solution compositions for insulating film substrates 4.1. Preparation of CMP polishing solution Hydrogen peroxide was added to a slurry using silicon oxide (W2000-V WIN, manufactured by Cabot) to a concentration of 4.5 wt % to obtain a CMP polishing solution.

[0060] 4.2. Preparation of the substrate to be polished A TEOS film substrate (plasma CVD 500 nm, manufactured by Global Net Co., Ltd.) and a silicon nitride film substrate (LP-CVD 100 nm, manufactured by Advanced Materials Technology Co., Ltd.) having the following configurations were prepared as insulating film substrates to be polished.

[0061] 4.3. Polishing and cleaning of insulating film substrate Using the above CMP polishing solution, the TEOS film substrate and the silicon nitride film substrate were each polished for 30 seconds using a polishing machine (model number: Poli-762, manufactured by G&P TECHNOLOGY). After polishing was completed, the substrates were brush scrubbed using the cleaning solution composition of Example 1 or Comparative Example 3 listed in Table 1 using a cleaning machine (model number: Cleaner812L, manufactured by G&P TECHNOLOGY) to obtain TEOS film substrates and silicon nitride film substrates for measurement.

[0062] 4.4. Measuring the number of defects on the surface of an insulating film substrate The number of defects (0.1 μm or larger) on the TEOS film substrate and silicon nitride film substrate for measurement was counted using a surface inspection device (model number: WM-10, manufactured by Takano Corporation). The number of defects after cleaning using the cleaning composition of Example 1 or Comparative Example 3 is shown in Table 2 and FIG. 3.

[0063] 5. Results [Table 2]

[0064] 2 and 3, it was confirmed that the cleaning liquid composition of Example 1, in which at least one of the surfactants is a polycarboxylic acid compound, exhibits cleaning performance and corrosion inhibition performance for molybdenum (Mo) films equivalent to those of the cleaning liquid composition of Comparative Example 3, which does not contain a polycarboxylic acid compound as a surfactant, and further exhibits cleaning performance for TEOS films and silicon nitride films higher than those of the cleaning liquid composition of Comparative Example 3, which does not contain a polycarboxylic acid compound as a surfactant.

Claims

1. A cleaning liquid composition for cleaning a substrate having a molybdenum (Mo)-containing film and an insulating film, the cleaning liquid composition comprising one or more reducing agents, two or more surfactants, and water, wherein at least one of the surfactants is a polycarboxylic acid compound, and the cleaning liquid composition has a pH of 7 or less.

2. The cleaning liquid composition according to claim 1, wherein the polycarboxylic acid compound is a polyacrylic acid compound.

3. The cleaning liquid composition according to claim 1 , wherein at least one of the surfactants is a polysulfonic acid compound.

4. 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.

5. 5. The cleaning liquid composition according to claim 4, wherein the hydroxylamine derivative is selected from the group consisting of N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine.

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

7. The cleaning liquid composition according to claim 6, wherein the pH adjuster is a quaternary ammonium compound or an inorganic acid.

8. 8. The cleaning liquid composition according to claim 7, wherein the quaternary ammonium compound is trimethyl-2-hydroxyethylammonium hydroxide.

9. 8. The cleaning solution composition of claim 7, wherein the inorganic acid is selected from the group consisting of nitric acid, sulfuric acid, hydrofluoric acid, and hydrochloric acid.

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 anticorrosive agent is a nitrogen-containing ring compound or a thiol compound.

12. 12. The cleaning liquid 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. 2. The cleaning liquid composition according to claim 1, wherein the insulating film is a tetraethoxysilane (TEOS) film or a silicon nitride (SiN) film.

15. 2. The concentrate composition for the cleaning liquid composition according to claim 1, which is used to obtain the cleaning liquid composition by diluting it 10 to 1000 times.

16. A method for cleaning a substrate having a molybdenum (Mo)-containing film and an insulating film, comprising the step of contacting the substrate having the molybdenum (Mo)-containing film and the insulating film with the cleaning liquid composition according to claim 1.

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

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

19. 18. The method for producing a semiconductor substrate according to claim 17, wherein the step of contacting the substrate having the molybdenum (Mo)-containing film and the insulating film is a step of cleaning the substrate having the molybdenum (Mo)-containing film and the insulating film.

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