Cleaning liquid composition

Abstract

The present invention addresses the problem of providing a cleaning liquid composition that has high pH stability and demonstrates good cleaning performance with regard to organic residues and abrasive grains that contain cobalt (Co), on a substrate that has a cobalt (Co) contact hole and / or cobalt (Co) wiring.　The present invention relates to a cleaning liquid composition for cleaning a substrate that has a cobalt (Co) contact plug and / or cobalt (Co) wiring, said cleaning liquid composition including one or more types of hydroxylamine derivatives as a reducing agent, one or more types of surfactants, one or more types of pH adjusting agents, and water, wherein the pH is 3 to 9.

Description

Cleaning composition

[0001] The present invention relates to a cleaning solution composition used for cleaning a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring.

[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 contaminants cause pattern defects, poor adhesion, and poor electrical properties, so they 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 with miniaturization, cobalt (Co) has come to be used in advanced devices as a material with lower electrical resistance than W. Furthermore, with miniaturization, the wiring (middle of line: MOL) that electrically connects these contact plugs to upper layer wiring is also shifting from copper (Cu) to cobalt (Co).

[0005] Cobalt (Co) has been used as a barrier metal or liner to prevent metal diffusion in copper (Cu) wiring in semiconductor manufacturing processes (see Patent Document 1). However, the cobalt (Co) used as the barrier metal or liner is very thin, and after chemical mechanical polishing (CMP), foreign matter called organic residues and abrasive particles derived from the slurry are unlikely to remain on the cobalt (Co). On the other hand, the cobalt (Co) contact plugs and wiring (MOL) have a larger cobalt (Co) area than the barrier metal or liner, and organic residues and abrasive particles are likely to remain on the cobalt (Co) after chemical mechanical polishing (CMP). A cleaning solution composition for substrates having such cobalt (Co) contact plugs and wiring has been proposed, and its excellent cleaning properties against organic residues and abrasive particles containing cobalt (Co) have been confirmed (see Patent Document 2).

[0006] US Patent Application Publication No. 2020 / 0199500 JP 2020-45453 A

[0007] The present inventors have encountered the problem that, in a cleaning solution composition for use after chemical mechanical polishing (CMP) of a substrate having a cobalt (Co) contact plug or interconnect, when a reducing agent selected from the group consisting of five- or six-membered ring compounds having two or more hydroxyl groups directly bonded to the ring, such as ascorbic acid, provides good cleaning performance against cobalt (Co)-containing organic residues and abrasive particles, but the pH of the cleaning solution composition changes over time and becomes unstable. Therefore, the present inventors have conducted research aimed at providing a cleaning solution composition for a substrate having a cobalt (Co) contact plug and / or cobalt (Co) interconnect that has high pH stability while ensuring good cleaning performance against cobalt (Co)-containing organic residues and abrasive particles. Specifically, the present invention aims to provide a cleaning solution composition that exhibits good cleaning performance against cobalt (Co)-containing organic residues and abrasive particles on a substrate having a cobalt (Co) contact plug and / or cobalt (Co) interconnect, and also has high pH stability.

[0008] 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 hydroxylamine derivatives as a reducing agent, one or more surfactants, one or more pH adjusters, and water, and having a pH of 3 or more and 9 or less, exhibits good cleaning properties for organic residues and abrasive grains containing cobalt (Co), and also exhibits high pH stability. As a result of further research, the present inventors have completed the present invention.

[0009] That is, the present invention relates to the following: [1] A cleaning liquid composition for cleaning a substrate having a cobalt (Co) contact plug and / or cobalt (Co) wiring, the cleaning liquid composition comprising one or more hydroxylamine derivatives as a reducing agent, one or more surfactants, one or more pH adjusters, and water, and having a pH of 3 or more and 9 or less. [2] The cleaning liquid composition according to [1] above, further comprising one or more corrosion inhibitors. [3] The cleaning liquid composition according to [1] above or [2] above, wherein the hydroxylamine derivative is selected from the group consisting of N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine.

[0010] [4] The cleaning liquid composition according to any one of [1] to [3] above, wherein the surfactant is a polysulfonic acid compound. [5] The cleaning liquid composition according to any one of [1] to [4] above, wherein the pH adjuster is a quaternary ammonium compound. [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 any one of [2] to [6] above, wherein the corrosion inhibitor is a nitrogen-containing ring compound. [8] The cleaning composition according to [7] above, wherein the nitrogen-containing ring compound is 3-mercapto-1,2,4-triazole.

[0011] [9] A stock solution composition for a cleaning liquid composition according to any one of [1] to [8] above, which is used to obtain the cleaning liquid composition by diluting it 10 to 1000 times.

[10] A method for cleaning a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring, comprising a step of contacting the cleaning liquid composition according to any one of [1] to [8] above with the substrate having the cobalt (Co) contact plug and / or the cobalt (Co) wiring.

[0012]

[11] A method for producing a semiconductor substrate, comprising the step of contacting a substrate having a cobalt (Co) contact plug and / or cobalt (Co) wiring with the cleaning liquid composition according to any one of [1] to [8] above.

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

[11] above, comprising the step of chemical mechanical polishing (CMP) the substrate having the cobalt (Co) contact plug and / or cobalt (Co) wiring before the step of contacting the cleaning liquid composition with the substrate having the cobalt (Co) contact plug and / or cobalt (Co) wiring.

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

[11] or

[12] above, wherein the step of contacting the substrate having the cobalt (Co) contact plug and / or cobalt (Co) wiring is a step of cleaning the substrate having the cobalt (Co) contact plug and / or cobalt (Co) wiring.

[0013] The cleaning liquid composition of the present invention can effectively remove metal impurities and fine particles, particularly organic residues and abrasive grains containing cobalt (Co), which are reaction products of cobalt (Co) and an organic corrosion inhibitor in a slurry, in a short time when cleaning the metal surface of a substrate that has been subjected to polishing, etching, chemical mechanical polishing (CMP), or the like in the manufacturing process of an electronic device such as a semiconductor element. The cleaning liquid composition of the present invention also exhibits high pH stability over time. By further containing an anticorrosion agent, the cleaning liquid composition of the present invention can suppress corrosion of metal materials such as cobalt (Co) on a substrate having a cobalt (Co) contact plug and / or cobalt (Co) wiring.

[0014] Fig. 1 is a graph showing the pH of the cleaning liquid compositions of Examples 1 to 4 and Comparative Examples 1 to 3 immediately after preparation (day 0) and one week after preparation (day 7). Fig. 2 is a graph showing the cleaning ability of the cleaning liquid compositions of Examples 5 to 13 and Comparative Examples 4 to 8 for removing post-CMP residues on Co-containing substrates. Fig. 3 is a graph showing the cleaning ability of the cleaning liquid compositions of Comparative Examples 9 and 10 for removing post-CMP residues on Co-containing substrates. Fig. 4 is a graph showing the cleaning ability of the cleaning liquid compositions of Comparative Examples 11 and 12 for removing post-CMP residues on Co-containing substrates.

[0015] The present invention will be described in detail below based on preferred embodiments of the present invention.

[0016] The present invention relates to a cleaning liquid composition for cleaning a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring, the cleaning liquid composition comprising one or more hydroxylamine derivatives as a reducing agent, one or more surfactants, one or more pH adjusters, and water, and having a pH of 3 or more and 9 or less.

[0017] Since cobalt (Co) corrodes under acidic conditions, a weakly alkaline to alkaline pH is generally selected for cleaning solutions. Common reducing agents used in the semiconductor industry, such as ascorbic acid and catechol, undergo deprotonation in the above pH range, resulting in increased reduction but also accelerated decomposition, resulting in poor stability.

[0018] The reducing agent used in the present invention is a hydroxylamine derivative. 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. ２Hydroxylamine derivatives are more stable than hydroxylamine derivatives (OH). On the other hand, hydroxylamine derivatives have the property of increasing reactivity by forming a complex with a metal (ion). That is, in a cleaning solution composition for cobalt (Co), the reactivity is selectively increased at the cobalt (Co) / cleaning solution composition interface, and they exhibit reducing properties. Therefore, the cleaning solution composition of the present invention containing the above hydroxylamine derivative maintains high stability even when it is weakly alkaline, and exhibits excellent reducing properties at the cobalt (Co) / cleaning solution composition interface during use, thereby achieving a cleaning effect.

[0019] The hydroxylamine derivatives include N,N-diethylhydroxylamine, N-methylhydroxylamine, and N,N-dimethylhydroxylamine, and preferably N,N-diethylhydroxylamine. One or more hydroxylamine derivatives can be used. The concentration of the hydroxylamine derivative in the cleaning liquid composition is not limited thereto, but is preferably 0.1 mM to 100 mM, and particularly preferably 1 mM to 10 mM.

[0020] From the viewpoint of stability, the cleaning liquid composition of the present invention preferably does not contain ascorbic acid, pyrogallol, or methyl gallate.

[0021] The surfactant used in the present invention is appropriately selected depending on the particulates 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, with polysulfonic acid compounds being preferred. Examples of polysulfonic acid compounds include naphthalenesulfonic acid formaldehyde condensates, polystyrene sulfonic acid, lignin sulfonic acid, and salts thereof, with naphthalenesulfonic acid formaldehyde condensates being preferred. One or more surfactants can 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.

[0022] The pH adjuster used in the present invention 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, potassium hydroxide, sodium hydroxide, and aqueous ammonium solutions, with quaternary ammonium compounds being preferred.

[0023] Specific examples of the quaternary ammonium compound 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, and particularly preferred is trimethyl-2-hydroxyethylammonium hydroxide (choline hydroxide). One or more pH adjusters can be used.

[0024] 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.

[0025] The cleaning liquid composition of the present invention contains water.

[0026] The pH of the cleaning liquid composition of the present invention is from 3 to 9. From the viewpoint of cleaning properties for organic residues containing cobalt (Co) and abrasive grains, the pH is preferably from 6 to 9.

[0027] In one embodiment, the cleaning liquid composition of the present invention may contain a corrosion inhibitor. Examples of the corrosion inhibitor include, but are not limited to, nitrogen-containing ring compounds and thiol compounds, and nitrogen-containing ring compounds are preferred.

[0028] 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-pyrazoline, Examples of the hydroxybenzotriazole include 1,2,3-triazole-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, 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 compound, from the viewpoints of industrial availability and high water solubility, 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 are preferred, and 3-mercapto-1,2,4-triazole is particularly preferred.

[0029] The concentration of the anticorrosive agent in the cleaning liquid composition is not limited to, but is preferably 0.01 mM to 100 mM, and particularly preferably 0.1 mM to 10 mM.

[0030] Examples of organic residues include, but are not limited to, organic residues containing cobalt (Co), which are dimers or oligomers of organometallic complexes cross-linked by cobalt (Co) generated by the reaction of cobalt (Co) with an organic corrosion inhibitor such as benzotriazole (BTA) contained in a chemical mechanical polishing (CMP) slurry during the CMP process. These organic residues are poorly soluble. The organic residues on the substrate to be cleaned with the cleaning solution composition of the present invention may contain high concentrations of cobalt (Co). To dissolve this organic residue containing cobalt (Co) in the cleaning solution composition, there is a method of changing the pH of the cleaning solution composition to break the coordinate bond between cobalt (Co) and the organic corrosion inhibitor and reduce the molecular weight of the residue.

[0031] Among the organic residues containing cobalt (Co), examples of dimers and oligomers of organometallic complexes cross-linked by cobalt (Co) that are generated by the reaction of cobalt (Co) with an organic corrosion inhibitor such as benzotriazole (BTA) during a chemical mechanical polishing (CMP) process include, but are not limited to, cobalt (Co)-benzotriazole (BTA) complexes.

[0032] The Co-BTA complex refers to a complex formed by crosslinking cobalt (Co) and benzotriazole (BTA), and is not limited to this, but includes a Co-BTA complex, a Cu-BTA complex, and silicon oxide (SiO ２ ) and compounds containing inorganic substances derived from a slurry.

[0033] The substrate having cobalt (Co) contact plugs and / or cobalt (Co) wiring 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 and a substrate immediately after processing the upper insulating film by dry etching after forming cobalt (Co) contact plugs and / or cobalt (Co) wiring. Of these, a substrate immediately after chemical mechanical polishing (CMP) is preferred.

[0034] 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

[0035] 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.

[0036] 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.

[0037] The cleaning liquid composition of the present invention is suitable for use on a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring, and is particularly suitable for use on a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring but not copper (Cu). It 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 cobalt (Co) organometallic complexes formed by a reaction between cobalt (Co) and a cobalt (Co) corrosion inhibitor contained in the slurry.

[0038] 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.

[0039] 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).

[0040] The present invention also relates to a method for cleaning a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring, comprising the step of contacting the substrate having the cobalt (Co) contact plug and / or the cobalt (Co) wiring with the cleaning liquid composition of the present invention.

[0041] The present invention still further relates to a method for producing a semiconductor substrate, which comprises a step of contacting a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring 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 the cobalt (Co) contact plug and / or the cobalt (Co) wiring before the step of contacting the substrate having the cobalt (Co) contact plug and / or the cobalt (Co) wiring with the cleaning liquid composition of the present invention.

[0042] 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 cobalt (Co) 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. Of 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 1. pH Stability Test 1.1. Preparation of Cleaning Liquid Compositions First, cleaning liquid compositions according to Examples 1 to 4 and Comparative Examples 1 to 3 were prepared. Specifically, as shown in Table 1, the cleaning liquid compositions according to Examples 1 to 4 and Comparative Examples 1 to 3 were prepared by adding a reducing agent, a surfactant, and / or a pH adjuster to water and mixing them.

[0047] 1.2. Evaluation The pH of the prepared cleaning liquid compositions was measured using a pH meter (manufactured by DKK-TOA, model number: HM-25R) on the day of preparation (day 0) and one week after preparation (day 7). The results are shown in Table 1 and Figure 1. In Table 1, DEHA is N,N-diethylhydroxylamine, and IONET D2 is a naphthalenesulfonic acid formaldehyde condensate.

[0048] The cleaning solutions of Examples 1 to 4 remained stable in pH even one week after production, and were particularly stable at a pH of 6 to 9. On the other hand, the cleaning solution compositions of Comparative Examples 1 to 3 were confirmed to have a pH change of 0.5 or more one week after production.

[0049] 2. Cleaning Properties of Cleaning Liquid Compositions for Cobalt (Co) Wafers 2.1. Preparation of Cleaning Liquid Compositions Cleaning liquid compositions according to Examples 5 to 13 and Comparative Examples 4 to 9 were prepared. Specifically, the cleaning liquid compositions according to Examples 5 to 13 and Comparative Examples 4 to 9 were prepared by adding a reducing agent, a surfactant, a pH adjuster, and / or an anticorrosive agent to water and mixing them, as shown in Table 2. Comparative Example 10 is an aqueous solution prepared by dissolving tetramethylammonium hydroxide (TMAH) in water and adjusting the pH. Comparative Examples 11 and 12 are cleaning liquid compositions manufactured by Kanto Chemical Co., Ltd., to be used after CMP. Comparative Example 11 is an alkaline post-CMP cleaning liquid for cobalt (Co) barrier metals, and Comparative Example 12 is an acidic post-CMP cleaning liquid for tantalum (Ta) barrier metals. Comparative Examples 11 and 12 do not contain a hydroxylamine derivative.

[0050] 2.2. Preparation of CMP Polishing Liquid A CMP polishing liquid was obtained by diluting a slurry using silicon oxide (manufactured by Resonac) with ultrapure water (DIW).

[0051] 2.3. Preparation of wafer to be polished A cobalt (Co) substrate with the following configuration was prepared (PVD-Co 2kÅ / Ti / Th—SiO ２ / Si, manufactured by Advanced Materials Technology Co., Ltd.).

[0052] 2.4. Polishing and Cleaning of Cobalt (Co) Wafers The above-mentioned wafers to be polished were polished for 30 seconds using the above CMP polishing solution with a polishing machine (CMP polishing machine manufactured by G&P Technology, model number: POLI-762). After polishing, the wafers were rinsed for 10 seconds with 100 mL of ultrapure water (DIW) while rotating. The rinsed wafers were cleaned for 60 seconds using each of the cleaning solution compositions listed in Tables 2 to 4 by rolling a polyvinyl alcohol brush (manufactured by Ion Co.) over the wafers while rotating. The cleaned wafers were rinsed for 30 seconds with 300 mL of ultrapure water (DIW) while rotating, and then dried for 30 seconds at 25°C while rotating to obtain wafers for measurement.

[0053] 2.5. Measurement of the number of defects on the surface of a cobalt (Co) wafer The number of defects on the surface of the wafer used for the measurement was measured using a surface inspection device (manufactured by Takano Corporation, model number: WM-10) to evaluate the cleaning performance of the cleaning liquid composition. The evaluation results are shown in Tables 2 to 4 and Figures 2 to 4.

[0054] 2.6. result In Table 2, DEHA is N,N-diethylhydroxylamine, IONET D2 is a naphthalenesulfonic acid formaldehyde condensate, and mTAZ is 3-mercapto-1,2,4-triazole.

[0055]

[0056] All of the cleaning liquid compositions of Examples 5 to 13 showed a defect count in the low triple digits, with the cleaning liquid composition of Example 10 exhibiting the best cleaning performance. The cleaning liquid compositions of Examples 5 to 13 exhibited cleaning performance comparable to or better than that of the cleaning liquid compositions of Comparative Examples 6 to 8, which had poor pH stability but good cleaning performance, and showed cleaning performance far superior to that of the TMAH aqueous solution of Comparative Example 10 and the commercially available cleaning liquid compositions of Comparative Examples 11 and 12. Furthermore, the cleaning liquid composition of Comparative Example 4 showed an increased number of defects, demonstrating that a surfactant is essential for improving cleaning performance in cleaning liquid compositions using hydroxylamine. Furthermore, the cleaning liquid composition of Comparative Example 5 exhibited insufficient cleaning performance despite containing the same components as Examples 6 to 13, demonstrating that cleaning performance cannot be ensured at a pH of 12.

Claims

1. A cleaning solution composition for cleaning a substrate having a cobalt (Co) contact plug and / or cobalt (Co) wiring, comprising one or more hydroxylamine derivatives as a reducing agent, one or more surfactants, one or more pH adjusters, and water, and having a pH of 3 or more and 9 or less.

2. The cleaning liquid composition according to claim 1, further comprising one or more anticorrosive agents.

3. The cleaning liquid composition according to claim 1 or 2, wherein the hydroxylamine derivative is selected from the group consisting of N,N-diethylhydroxylamine, N-methylhydroxylamine and N,N-dimethylhydroxylamine.

4. A cleaning liquid composition according to any one of claims 1 to 3, wherein the surfactant is a polysulfonic acid compound.

5. A cleaning liquid composition according to any one of claims 1 to 4, wherein the pH adjuster is a quaternary ammonium compound.

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 any one of claims 2 to 6, wherein the corrosion inhibitor is a nitrogen-containing ring compound.

8. The cleaning composition according to claim 7, wherein the nitrogen-containing ring compound is 3-mercapto-1,2,4-triazole.

9. A concentrate composition for a cleaning liquid composition according to any one of claims 1 to 8, which is used to obtain the cleaning liquid composition by diluting the concentrate composition 10 to 1,000 times.

10. A method for cleaning a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring, comprising a step of contacting a substrate having a cobalt (Co) contact plug and / or a cobalt (Co) wiring with the cleaning liquid composition according to any one of claims 1 to 8.

11. A method for producing a semiconductor substrate, comprising a step of contacting a substrate having a cobalt (Co) contact plug and / or cobalt (Co) wiring with the cleaning liquid composition according to any one of claims 1 to 8.

12. The method for producing a semiconductor substrate according to claim 11, further comprising a step of chemically mechanically polishing (CMP) the substrate having the cobalt (Co) contact plug and / or the cobalt (Co) wiring prior to the step of contacting the substrate having the cobalt (Co) contact plug and / or the cobalt (Co) wiring.

13. The method for manufacturing a semiconductor substrate according to claim 11 or 12, wherein the step of contacting a substrate having a cobalt (Co) contact plug and / or cobalt (Co) wiring is a step of cleaning the substrate having a cobalt (Co) contact plug and / or cobalt (Co) wiring.

Images