JP6283057B2 - Storage method and cleaning method for semiconductor cleaning composition - Google Patents

Description

  The present invention relates to a storage method and a cleaning method for a semiconductor cleaning composition.

  CMP (Chemical Mechanical Polishing) used for manufacturing a semiconductor device is a chemical mechanical polishing aqueous dispersion (hereinafter also simply referred to as “CMP slurry”) on a polishing pad by pressing a polishing target to the polishing pad. This is a technique for chemically and mechanically polishing the object to be polished by sliding the object to be polished and the polishing pad with each other. The CMP slurry used for such CMP contains chemicals such as an etching agent in addition to abrasive grains. Then, polishing scraps are generated by CMP. If these polishing scraps remain on the object to be polished, a fatal device defect may occur. For this reason, a process of cleaning the object to be polished with the cleaning composition is essential after the CMP.

  A metal wiring material such as copper and tungsten, an insulating material such as silicon oxide, and a barrier metal material such as tantalum nitride and titanium nitride are exposed on the surface of the object to be polished after CMP. When such different materials coexist on the surface to be polished, it is necessary to remove only the contamination from the surface to be polished and clean the surface without causing damage such as corrosion. For example, Patent Document 1 discloses a technique for suppressing corrosion of a surface to be polished where a wiring material and a barrier metal material are exposed using an acidic cleaning agent. For example, Patent Document 2 and Patent Document 3 disclose a technique for cleaning a surface to be polished from which a wiring material and a barrier metal material such as cobalt are exposed using a neutral to alkaline cleaning agent.

JP 2010-258014 A JP 2009-055020 A JP2013-157516A

  However, a variety of components are added to the cleaning agent used for cleaning after CMP because it has the property of removing contamination on the surface to be polished and preventing the contamination from adhering to the surface to be polished during cleaning. I can't. Therefore, the cleaning agent used for cleaning after CMP is liable to generate foreign matters and discoloration during storage, and has been problematic in storage stability. Such a slight change in the state of the cleaning agent may not only remove contamination of the surface to be polished, but also may damage the surface to be polished by cleaning.

  Accordingly, some aspects of the present invention provide a storage method that is excellent in storage stability of a semiconductor cleaning composition by solving at least a part of the above problems, and a semiconductor cleaning composition stored by the method A cleaning method using this is provided.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following aspects or application examples.

[Application Example 1]
One aspect of the method for storing a semiconductor cleaning composition according to the present invention is:
A method of storing a semiconductor cleaning composition by filling the container,
The ratio of the volume of the void portion excluding the volume occupied by the semiconductor cleaning composition to the internal volume of the container is 5 to 20%,
The oxygen concentration in the void is 0 to 5%,
It is characterized by being stored at a temperature of 5 ° C. or higher and 40 ° C. or lower.

[Application Example 2]
In the storage method of Application Example 1,
The semiconductor cleaning composition may be filtered with a depth-type or pleat-type filter.

[Application Example 3]
In the storage method of application example 2,
The filtration accuracy of the filtration filter may be 0.01 to 20 μm.

[Application Example 4]
In the storage method of any one of application examples 1 to 3,
The semiconductor cleaning composition may contain 3 × 10 ^{1 to} 1.5 × 10 ³ particles / mL of 0.1 to 0.3 μm particles.

[Application Example 5]
In the storage method of any one of application examples 1 to 4,
The semiconductor cleaning composition contains potassium and sodium,
When the potassium content is M _K (ppm) and the sodium content is M _Na (ppm), M _K / M _Na = 5 × 10 ³ to 1 × 10 ⁵ can be obtained.

[Application Example 6]
In the storage method according to any one of Application Example 1 to Application Example 5,
The semiconductor cleaning composition may contain an organic acid.

[Application Example 7]
In the storage method of any one of application examples 1 to 6,
The semiconductor cleaning composition may contain a water-soluble polymer.

[Application Example 8]
In the storage method according to any one of Application Example 1 to Application Example 7,
The semiconductor cleaning composition may be used after being diluted 1 to 500 times.

[Application Example 9]
One aspect of the cleaning method according to the present invention is:
Application examples 1 to 3 are applied to wiring boards containing copper or tungsten as a wiring material and at least one selected from the group consisting of tantalum, titanium, cobalt, ruthenium, manganese, and compounds thereof as a barrier metal material. It is characterized by including the process of wash | cleaning using the composition for semiconductor washing | cleaning stored by the method of any one example of Example 8.

[Application Example 10]
One aspect of the cleaning method according to the present invention is:
Tungsten was contained as a wiring material of the wiring board, and the wiring board was stored by the method of any one of application examples 1 to 8 after chemical mechanical polishing using a composition containing iron ions and peroxides. It includes a step of cleaning with a semiconductor cleaning composition.

  According to the storage method of the present invention, since the storage stability of the semiconductor cleaning composition is improved, a stable semiconductor cleaning composition can be provided at any time.

It is a conceptual diagram which shows typically the structure of the filtration apparatus used by this embodiment. It is sectional drawing which shows typically the preparation process of the wiring board used for the cleaning method which concerns on this embodiment. It is sectional drawing which shows typically the preparation process of the wiring board used for the cleaning method which concerns on this embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail. In addition, this invention is not limited to the following embodiment, Various modifications implemented in the range which does not change the summary of this invention are also included.

1. Semiconductor cleaning composition The semiconductor cleaning composition used in the present embodiment is diluted with an aqueous medium such as pure water as necessary, and particles and metals mainly present on the surface of the polishing target after completion of CMP. It can be used as a cleaning agent for removing impurities and the like. Hereinafter, each component contained in the composition for semiconductor cleaning used by this embodiment is demonstrated in detail.

1.1. Particles with a Particle Diameter of 0.1 to 0.3 μm The semiconductor cleaning composition used in the present embodiment is a 3 × particle having a particle diameter of 0.1 to 0.3 μm (hereinafter also referred to as “specific particles”). It can contain 10 < ¹ > -1.5 * 10 < ³ > pieces / mL. It is considered that the semiconductor cleaning composition used in this embodiment can effectively scrape off and remove polishing debris remaining on the surface to be polished in the cleaning step by containing specific particles in a predetermined ratio. On the other hand, when the content ratio of the specific particles contained in the semiconductor cleaning composition exceeds the above range, the specific particles remain on the polished surface after cleaning, and the electrical characteristics of the semiconductor circuit as the object to be cleaned This is not preferable because a decrease in yield due to deterioration is induced. On the other hand, when the content ratio of the specific particles contained in the semiconductor cleaning composition is smaller than the above range, it becomes difficult to effectively scrape off polishing scraps adhering to the surface to be polished, and the flatness of the cleaning surface deteriorates. It is thought that it will end.

  Generally, as described in International Publication No. 1999/049997 and the like, particles are recognized as foreign matters to be removed as much as possible in the manufacturing process of a semiconductor device. However, in the present invention, when the surface to be polished is cleaned using a composition for cleaning a semiconductor that covers the conventional concept and contains particles having a particle diameter of 0.1 to 0.3 μm in a predetermined ratio. It has been found that the semiconductor characteristics are not significantly deteriorated, and conversely, the cleaning characteristics are improved.

  The specific particles contained in the semiconductor cleaning composition used in the present embodiment are preferably metal particles or metal oxide particles, and more preferably insulating particles.

Examples of such metal particles and metal oxide particles include iron, titanium, aluminum, zirconium, magnesium, and oxides of these metals (iron oxide, titania, alumina, zirconia, magnesia, etc.), silica, and stainless steel. (SUS201, 202, 301, 302, 303, 304, 305, 316, 317, 403, 405, 420, 430, 630, etc.) can be used. Among these, iron oxide, stainless steel, titanium oxide, silica, and aluminum oxide are preferable, and silica is more preferable from the viewpoint that polishing debris attached to the surface to be polished can be effectively removed without deteriorating the electrical characteristics of the semiconductor circuit. preferable.

  The specific particles preferably have a ratio (Rmax / Rmin) of the major axis (Rmax) to the minor axis (Rmin) of 1.3 or more, more preferably 1.4 or more and 3.0 or less, and particularly preferably 1. It is preferable to contain specific particles having a shape of 5 or more and 2.5 or less (hereinafter also referred to as “specific shape particles”). When the semiconductor cleaning composition used in the present embodiment contains the specific shaped particles, the effect of removing polishing debris attached to the surface to be polished is improved. In addition, since the specifically shaped particles have a concavo-convex shape, components such as a water-soluble polymer, an organic acid, and an amine, which will be described later, can be taken into or released from the concave portion. For this reason, it is considered that these components act effectively by being released in the cleaning process.

  When the total mass of the specific particles contained in the semiconductor cleaning composition used in this embodiment is 100 parts by mass, the specific particles preferably contain 30 parts by mass or more of specific shaped particles, and 40 parts by mass or more. It is more preferable to contain, and it is especially preferable to contain 50 parts by mass or more.

  Here, the major axis (Rmax) of the particle is a distance passing through the center of gravity of the particle image and connecting the end portion of the particle image with respect to one independent particle image taken by a transmission electron microscope. Means the longest distance. On the other hand, the minor axis (Rmin) of the particle is a distance passing through the center of gravity of the particle image and connecting the end portions of the particle image with respect to one independent particle image taken by a transmission electron microscope. Means the shortest distance.

  Here, the particle diameter of the particles and the content of the particles in the semiconductor cleaning composition can be measured using a particle size distribution measuring apparatus based on a laser diffraction method. The particle size in the present invention is a value of a particle size (D50) at which the cumulative frequency of the number of particles is 50% when the particle size distribution is measured using the particle size distribution measuring device and the particles are accumulated from small particles. . Examples of such a laser diffraction particle size distribution measuring apparatus include HORIBA LA-300 series, HORIBA LA-920 series (above, manufactured by Horiba, Ltd.) and the like. This particle size distribution measuring apparatus does not only evaluate the primary particles of the particles, but also evaluates the secondary particles formed by aggregation of the primary particles. Therefore, the particle diameter obtained by this particle size distribution measuring apparatus can be used as an index of the dispersion state of the particles contained in the semiconductor cleaning composition.

  Note that in CMP of an object to be polished having tungsten as a wiring material, a CMP slurry containing iron ions and peroxides (hydrogen peroxide, potassium iodate, etc.) is used. Since iron ions contained in the CMP slurry are easily adsorbed on the surface of the object to be polished, the surface to be polished is easily contaminated with iron. In this case, it is considered that by cleaning the surface to be polished using the semiconductor cleaning composition used in this embodiment, the specific particles can be effectively removed by scraping off the iron contamination of the surface to be polished.

1.2. Potassium and sodium The semiconductor cleaning composition used in the present embodiment can contain potassium and sodium. Generally, as described in Japanese Patent Application Laid-Open No. 2000-208451 and the like, in a semiconductor manufacturing process, alkali metals such as sodium and potassium are recognized as impurities to be removed as much as possible. Therefore, also in the CMP slurry, an organic base such as tetramethylammonium hydroxide (TMAH) is used as a base for controlling pH, not an inorganic base such as sodium hydroxide. However, in the present invention, the conventional concept is overturned, and in the cleaning process after the CMP polishing, the semiconductor characteristics are not significantly deteriorated by using a semiconductor cleaning composition containing potassium and sodium at a predetermined ratio. On the other hand, it has been found that there is an effect of improving the cleaning characteristics.

The content ratio of potassium and sodium in the semiconductor cleaning composition according to the present embodiment is M _K / M _Na when the potassium content is M _K (ppm) and the sodium content is M _Na (ppm). = 5 × 10 ³ to 1 × 10 ⁵ is preferable, 5.5 × 10 ^{3 to} 9.5 × 10 ⁴ is more preferable, and 6 × 10 ^{3 to} 9 × 10 ⁴ is more preferable. More preferably, it is particularly preferably 7 × 10 ³ to 8 × 10 ⁴ . When the content ratio of potassium and sodium is within the above range, it is considered that metal materials such as copper and tungsten exposed on the surface to be polished can be prevented from being excessively etched and eluted in the semiconductor cleaning process. . On the other hand, when the ratio of sodium and potassium contained in the semiconductor cleaning composition exceeds the above range, the semiconductor circuit that is the object to be cleaned remains, with sodium and potassium remaining attached to the object to be cleaned after cleaning. This is not preferable because a decrease in yield due to deterioration of the electrical characteristics is induced. On the other hand, when the ratio of sodium and potassium contained in the semiconductor cleaning composition is less than the above range, the ion product of sodium and potassium existing in the cleaning material and a metal material such as copper and tungsten exposed on the surface to be polished. Therefore, it is considered that the etching of a metal material such as copper or tungsten proceeds and the flatness of the cleaning surface deteriorates.

The semiconductor cleaning composition used in this embodiment preferably contains 1 × 10 ⁻⁶ to 10 × 10 ⁰ ppm of sodium, and more preferably contains 4 × 10 ^{−6 to} 6 × 10 ⁰ ppm. Moreover, it is preferable that the composition for semiconductor cleaning used by this embodiment contains 1 * 10 < ^-1 > -5 * 10 < ⁴ > ppm potassium, and contains 1.2 * 10 < ^-1 > -4 * 10 < ⁴ > ppm. Is more preferable. When potassium and sodium are contained in the above-mentioned content ratio, and the content of potassium and sodium is within the above range, metal materials such as copper and tungsten exposed on the surface to be polished are excessively etched in the cleaning process. It is thought that it is possible to more effectively suppress elution and maintain stable washing characteristics.

  The semiconductor cleaning composition used in the present embodiment can contain potassium or sodium in the semiconductor cleaning composition by blending potassium or sodium as a water-soluble salt. Examples of such water-soluble salts include sodium and potassium hydroxides, carbonates, ammonium salts, halides, and the like.

In the present invention, the content of potassium contained in the semiconductor cleaning composition is M _K (ppm) and the content of sodium is M _Na (ppm). -AES), ICP mass spectrometry (ICP-MS) or atomic absorption photometry (AA) can be used for determination. As the ICP emission analyzer, for example, “ICPE-9000 (manufactured by Shimadzu Corporation)” or the like can be used. As the ICP mass spectrometer, for example, “ICPM-8500 (manufactured by Shimadzu Corporation)”, “ELAN DRC PLUS (manufactured by Perkin Elmer)” or the like can be used. As the atomic absorption analyzer, for example, “AA-7000 (manufactured by Shimadzu Corporation)”, “ZA3000 (Hitachi High-Tech Science Co., Ltd.)”, and the like can be used.

  Note that in CMP of an object to be polished having tungsten as a wiring material, a CMP slurry containing iron ions and peroxides (hydrogen peroxide, potassium iodate, etc.) is used. Since iron ions contained in the CMP slurry are easily adsorbed on the surface of the object to be polished, the surface to be polished is easily contaminated with iron. In this case, the surface to be polished is cleaned using the semiconductor cleaning composition used in the present embodiment, thereby promoting the generation of a readily soluble salt such as potassium tungstate or sodium tungstate in the cleaning process. Thereby, it is considered that metal contamination on the wiring substrate can be reduced, and polishing residues can be efficiently removed while reducing damage to the object to be polished.

1.3. Other Components The semiconductor cleaning composition used in the present embodiment can contain a water-soluble polymer, an organic acid, an amine, and other components in addition to an aqueous medium as a main component.

1.3.1. Water-soluble polymer The composition for semiconductor cleaning used in the present embodiment can contain a water-soluble polymer. The water-soluble polymer has a function of reducing corrosion by adsorbing on the surface of the surface to be cleaned. Therefore, when a water-soluble polymer is added to the semiconductor cleaning composition, corrosion of the surface to be cleaned can be reduced. In the present invention, “water-soluble” means that the mass dissolved in 100 g of water at 20 ° C. is 0.1 g or more. In the present invention, the “water-soluble polymer” refers to a water-soluble compound in which two or more repeating units are linked in a linear or network form through a covalent bond.

Examples of such water-soluble polymers include polyacrylic acid, polymethacrylic acid, polymaleic acid, polyvinyl sulfonic acid, polyallyl sulfonic acid, polystyrene sulfonic acid, and salts thereof;
Copolymers of monomers such as styrene, α-methylstyrene, 4-methylstyrene, and acid monomers such as (meth) acrylic acid and maleic acid, and aromatics obtained by condensing benzenesulfonic acid, naphthalenesulfonic acid, etc. with formalin A polymer having a repeating unit having an aromatic hydrocarbon group and a salt thereof;
Vinyl synthetic polymers such as polyvinyl alcohol, polyoxyethylene, polyvinyl pyrrolidone, polyvinyl pyridine, polyacrylamide, polyvinyl formamide, polyethylene imine, polyvinyl oxazoline, polyvinyl imidazole, polyallylamine; natural polysaccharides such as hydroxyethyl cellulose, carboxymethyl cellulose, and modified starch Modified product of
However, it is not limited to these. These water-soluble polymers can be used singly or in combination of two or more.

  The water-soluble polymer used in the present embodiment may be a homopolymer or a copolymer obtained by copolymerizing two or more monomers. Examples of such a monomer include a monomer having a carboxyl group, a monomer having a sulfonic acid group, a monomer having a hydroxyl group, a monomer having a polyethylene oxide chain, and a monomer having an amino group A monomer having a heterocyclic ring can be used.

  The weight average molecular weight (Mw) of the water-soluble polymer used in the present embodiment is preferably from 1,000 to 1,500,000, more preferably from 3,000 to 1,200,000. In the present specification, “weight average molecular weight” refers to a weight average molecular weight in terms of polyethylene glycol measured by GPC (gel permeation chromatography).

  The content of the water-soluble polymer is preferably adjusted so that the viscosity of the semiconductor cleaning composition at room temperature is 2 mPa · s or less. When the viscosity of the semiconductor cleaning composition at room temperature exceeds 2 mPa · s, the semiconductor cleaning composition may not be stably supplied to the object to be cleaned because the viscosity becomes too high. Since the viscosity of the semiconductor cleaning composition is almost determined by the weight average molecular weight and content of the water-soluble polymer to be added, it may be adjusted in consideration of the balance between them.

In addition, the content of the water-soluble polymer is determined by the following: metal wiring material such as copper and tungsten exposed on the surface of the polished object after CMP, which is the object to be cleaned, insulating material such as silicon oxide, tantalum nitride and titanium nitride It can be changed as appropriate depending on the material such as a barrier metal material and the composition of the CMP slurry used.

  Furthermore, it can change suitably also by the dilution degree of the composition for semiconductor cleaning used by this embodiment. In this case, the content of the water-soluble polymer is preferably 0.001 part by mass or more, more preferably 0.001 part by mass or less with respect to 100 parts by mass of the cleaning agent prepared by diluting the semiconductor cleaning composition. The upper limit is preferably 1 part by mass or less, more preferably 0.1 part by mass or less. When the content of the water-soluble polymer is within the above range, both the suppression of corrosion and the effect of removing particles and metal impurities contained in the CMP slurry from the wiring board are promoted, and the better A surface to be cleaned is easily obtained.

1.3.2. Organic Acid The semiconductor cleaning composition used in the present embodiment can contain an organic acid. The organic acid preferably has one or more acidic groups such as a carboxy group and a sulfo group. The “organic acid” in the present invention is a concept that does not include the above-mentioned water-soluble polymer.

  Specific examples of organic acids include citric acid, maleic acid, malic acid, tartaric acid, oxalic acid, malonic acid, succinic acid, ethylenediaminetetraacetic acid, acrylic acid, methacrylic acid, benzoic acid, phenyllactic acid, hydroxyphenyllactic acid, phenylsuccinic acid. Examples thereof include acids, naphthalenesulfonic acid, and salts thereof. These organic acids may be used alone or in combination of two or more.

  An amino acid may be used as the organic acid. Examples of amino acids include compounds represented by the following general formula (1).

（上記一般式（１）中、Ｒ^１は水素原子、炭素数１〜１０の炭化水素基およびヘテロ原子を有する炭素数１〜２０の有機基よりなる群から選択されるいずれかを示す。）

(In the general formula (1), R ¹ represents any one selected from the group consisting of a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, and an organic group having 1 to 20 carbon atoms having a hetero atom.)

Examples of the hydrocarbon group having 1 to 10 carbon atoms in R ¹ in the general formula (1) include a saturated aliphatic hydrocarbon group having 1 to 10 carbon atoms, a cyclic saturated hydrocarbon group having 1 to 10 carbon atoms, and carbon. A C6-C10 aromatic hydrocarbon group etc. can be mentioned, Among these, a C1-C10 saturated aliphatic hydrocarbon group is preferable.

Examples of the organic group having 1 to 20 carbon atoms having a heteroatom in R ¹ in the general formula (1) include, for example, a hydrocarbon group having 1 to 20 carbon atoms having a carboxy group and 1 to 20 carbon atoms having a hydroxyl group. A hydrocarbon group having 1 to 20 carbon atoms having an amino group, a hydrocarbon group having 1 to 20 carbon atoms having a mercapto group, an organic group having 1 to 20 carbon atoms having a heterocyclic ring, and the like. These groups may further contain heteroatoms such as oxygen, sulfur, and halogen, and a part thereof may be substituted with other substituents.

Examples of the compound represented by the above formula (1) include alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, isoleucine, leucine, lysine, methionine, phenylalanine, serine, threonine, tyrosine, parin, tryptophan, Examples thereof include histidine and 2-amino-3-aminopropanoic acid. These amino acids may be used alone or in combination of two or more.

  As the organic acid, it is also preferable to use a compound represented by the following general formula (2).

（上記一般式（２）中、Ｒ^２は、炭素数１〜２０の有機基を示す。）

(In the general formula (2), R ² represents an organic group having 1 to 20 carbon atoms.)

Examples of the organic group having 1 to 20 carbon atoms in R ² in the general formula (2) include a saturated aliphatic hydrocarbon group having 6 to 20 carbon atoms and an unsaturated aliphatic hydrocarbon group having 6 to 20 carbon atoms, An organic group having 6 to 20 carbon atoms having a cyclic saturated hydrocarbon group, an organic group having 6 to 20 carbon atoms having an unsaturated cyclic hydrocarbon group, a hydrocarbon group having 1 to 20 carbon atoms having a carboxy group, and a hydroxyl group. Examples thereof include a hydrocarbon group having 1 to 20 carbon atoms, a hydrocarbon group having 1 to 20 carbon atoms having an amino group, and an organic group having 1 to 20 carbon atoms having a heterocyclic group. The C6-C20 organic group which has a C6-C20 organic group which has a hydrocarbon group, or a carboxy group is preferable, and the C6-C20 organic group or carboxymethyl group which has an aryl group is especially preferable. However, the compound represented by the general formula (2) excludes the compound represented by the general formula (1).

  Specific examples of the compound represented by the general formula (2) include hydroxyphenyl lactic acid and hydroxymalonic acid, and among these, hydroxyphenyl lactic acid is preferable. The compounds exemplified above may be used alone or in combination of two or more.

  The organic acid content is determined by the following: metal wiring material such as copper and tungsten exposed on the surface of the object to be cleaned after CMP, which is the object to be cleaned, insulating material such as silicon oxide, and barrier metal such as tantalum nitride and titanium nitride It can be appropriately changed depending on the material such as the material and the composition of the used CMP slurry.

  Furthermore, it can change suitably also by the dilution degree of the composition for semiconductor cleaning used by this embodiment. In this case, the lower limit of the content of the organic acid is preferably 0.0001 parts by mass or more, more preferably 0.0005 parts by mass with respect to 100 parts by mass of the cleaning agent prepared by diluting the semiconductor cleaning composition. The upper limit is preferably 1 part by mass or less, more preferably 0.5 part by mass or less. When the content of the organic acid is within the above range, impurities attached to the surface of the wiring material can be effectively removed. Moreover, the progress of excessive etching can be suppressed more effectively, and a good cleaning surface can be obtained.

1.3.3. Amine The semiconductor cleaning composition used in the present embodiment may contain an amine (excluding amino acids). The amine is considered to have a function as an etching agent. By adding an amine, a metal oxide film (for example, CuO, Cu ₂ O and Cu (OH) ₂ layer) and an organic residue (for example, BTA layer) on the wiring substrate are etched in a cleaning process after the completion of CMP. It can be removed.

The amine is preferably a water-soluble amine. The definition of “water-soluble” is as described above, and means that the mass dissolved in 100 g of water at 20 ° C. is 0.1 g or more.
Examples of the amine include alkanolamines, primary amines, secondary amines, and tertiary amines.

  As alkanolamine, monoethanolamine, diethanolamine, triethanolamine, N-methylethanolamine, N-methyl-N, N-diethanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, N, N -Dibutylethanolamine, N- (β-aminoethyl) ethanolamine, N-ethylethanolamine, monopropanolamine, dipropanolamine, tripropanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine and the like. Examples of the primary amine include methylamine, ethylamine, propylamine, butylamine, pentylamine, 1,3-propanediamine and the like. Secondary amines include piperidine, piperazine and the like. Examples of the tertiary amine include trimethylamine and triethylamine. These amines may be used individually by 1 type, and may be used in mixture of 2 or more types.

  Among these amines, monoethanolamine and monoisopropanolamine are preferable, and monoethanolamine is more preferable in that the effect of etching the metal oxide film and the organic residue on the wiring board is high.

  The content of the amine is the metal wiring material such as copper and tungsten exposed on the surface of the object to be cleaned after CMP which is the object to be cleaned, the insulating material such as silicon oxide, and the barrier metal material such as tantalum nitride and titanium nitride. The material can be appropriately changed depending on the material of the CMP slurry and the composition of the CMP slurry used.

  Furthermore, it can change suitably also by the dilution degree of the composition for semiconductor cleaning used by this embodiment. In this case, the lower limit of the amine content is preferably 0.0001 parts by mass or more, more preferably 0.0005 parts by mass with respect to 100 parts by mass of the cleaning agent prepared by diluting the semiconductor cleaning composition. The upper limit is preferably 1 part by mass or less, more preferably 0.5 part by mass or less. When the amine content is within the above range, the metal oxide film and the organic residue on the wiring substrate can be more effectively etched and removed in the cleaning process after the CMP is completed.

1.3.4. Aqueous medium The semiconductor cleaning composition used in the present embodiment is a liquid mainly composed of an aqueous medium. The aqueous medium is not particularly limited as long as it can serve as a solvent mainly composed of water. Examples of such an aqueous medium include water, a mixed medium of water and alcohol, a mixed medium containing water and an organic solvent having compatibility with water. Among these, water, a mixed medium of water and alcohol are preferably used, and water is more preferably used.

1.3.5. Other Components The semiconductor cleaning composition used in the present embodiment may contain necessary components in a timely manner, and may contain, for example, a pH adjuster or a surfactant.

<PH adjuster>
In the semiconductor cleaning composition according to the present embodiment, when a surface to be polished containing copper as a wiring material is cleaned, the lower limit value of the pH is preferably 9 or more, more preferably 10 or more, The upper limit is preferably 14 or less. When cleaning the surface to be polished containing tungsten as a wiring material, the upper limit of pH is preferably 7 or less, more preferably 6 or less, and the lower limit of pH is preferably 2 or more.

  In the semiconductor cleaning composition used in the present embodiment, when a desired pH cannot be obtained by adding the organic acid or amine described above, a pH adjuster is added to adjust the pH within the above range. May be. Examples of the pH adjuster include alkali metal hydroxides such as sodium hydroxide, potassium hydroxide, rubidium hydroxide and cesium hydroxide, organic ammonium salts such as tetramethylammonium hydroxide, and basic compounds such as ammonia. Can be mentioned. These pH adjusting agents may be used alone or in combination of two or more.

<Surfactant>
As the surfactant, known components can be used in a timely manner, but a nonionic surfactant or an anionic surfactant can be preferably used. By adding the surfactant, the effect of removing particles and metal impurities contained in the CMP slurry from the wiring substrate is enhanced, and a better surface to be cleaned may be obtained in some cases.

  Examples of nonionic surfactants include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether; polyoxyethylene octylphenyl ether, polyoxy Polyoxyethylene aryl ethers such as ethylene nonylphenyl ether; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate; polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxy And polyoxyethylene sorbitan fatty acid esters such as ethylene sorbitan monostearate. The nonionic surfactants exemplified above may be used singly or in combination of two or more.

  Examples of the anionic surfactant include alkylbenzene sulfonic acids such as dodecylbenzene sulfonic acid; alkyl naphthalene sulfonic acids; alkyl sulfates such as lauryl sulfate; sulfates of polyoxyethylene alkyl ethers such as polyoxyethylene lauryl sulfate; naphthalene Examples include sulfonic acid condensates; alkyliminodicarboxylic acids; lignin sulfonic acids and the like. These anionic surfactants may be used in the form of a salt. In this case, examples of the counter cation include sodium ion, potassium ion, and ammonium ion, and ammonium ion is preferable from the viewpoint of preventing excessive inclusion of potassium and sodium in the semiconductor cleaning composition.

  In CMP of an object to be polished having tungsten as a wiring material, a CMP slurry containing iron ions and peroxides (hydrogen peroxide, potassium iodate, etc.) is used. Since iron ions contained in the CMP slurry are easily adsorbed on the surface of the object to be polished, the surface of the object to be polished is easily contaminated with iron. In this case, since iron ions are charged positively, iron contamination on the surface of the object to be polished may be effectively removed by adding an anionic surfactant to the semiconductor cleaning composition.

  The content of the surfactant is the metal wiring material such as copper and tungsten exposed on the surface of the object to be cleaned after CMP, which is the object to be cleaned, the insulating material such as silicon oxide, and the barrier such as tantalum nitride and titanium nitride. It can be appropriately changed depending on the material such as a metal material and the composition of the CMP slurry used.

Furthermore, it can change suitably also by the dilution degree of the composition for semiconductor cleaning used by this embodiment. In this case, the content of the surfactant is preferably 0.001 part by mass or more and 1 part by mass or less with respect to 100 parts by mass of the detergent prepared by diluting the semiconductor cleaning composition. When the content of the surfactant is within the above range, the organic residue can be efficiently removed while reducing the corrosion of the object to be cleaned in the cleaning step after the completion of CMP.

1.4. Method for Preparing Semiconductor Cleaning Composition The semiconductor cleaning composition used in the present embodiment is not particularly limited, and can be prepared by using a known method. Specifically, it can be prepared by dissolving each component described above in an aqueous medium such as water and filtering. There are no particular restrictions on the mixing order or mixing method of the components described above.

  In the method for preparing a semiconductor cleaning composition used in the present embodiment, it is preferable to control the amount of particles by filtering with a depth type or pleat type filter, if necessary. Here, the depth type filter is a high-precision filtration filter that is also referred to as a depth filtration or volume filtration type filter. Such depth type filters include those having a laminated structure in which filtration membranes having a large number of pores are laminated, and those in which fiber bundles are wound up. Specific examples of depth type filters include Profile II, Nexis NXA, Nexis NXT, Polyfine XLD, Ultiplez Profile, etc. (all manufactured by Nippon Pole), depth cartridge filters, wind cartridge filters, etc. (all, Advantech) Co., Ltd.), CP filter, BM filter, etc. (all manufactured by Chisso Corporation), slope pure, diamond, micro-Syria, etc. (all manufactured by Loki Techno Co.), and the like.

  As a pleated type filter, a microfiltration membrane sheet made of non-woven fabric, filter paper, metal mesh, etc. is fold-folded and then molded into a cylindrical shape, and the seam of the pleats of the sheet is sealed in a liquid-tight manner. A cylindrical high-precision filtration filter obtained by sealing both ends of the liquid-tightly. Specifically, HDCII, Polyfine II, etc. (all manufactured by Nihon Pall), PP pleated cartridge filter (manufactured by Advantech), Porous Fine (manufactured by Chisso), Sirton Pore, Micropure, etc. (all, manufactured by Loki Techno) Etc.

  It is preferable to use a filter having a rated filtration accuracy of 0.01 to 20 μm. By using a filter having a rated filtration accuracy within the above range, it is possible to efficiently obtain a filtrate in which the number of particles having a particle diameter of 20 μm or more per mL is 0 when measured with a particle counter. Also, the usable period of the filter is extended because the number of coarse particles trapped in the filter is minimized.

  Conditions for filtration (pressure difference before and after the filter (differential pressure), liquid temperature, etc.) may be set as appropriate within the range where the differential pressure does not exceed the maximum differential pressure resistance of the filter to be used. It is preferably 0.2 to 0.4 MPaG. The liquid temperature is preferably 10 to 50 ° C. The linear velocity is preferably 11 to 150 L / min, and more preferably 13 to 130 L / min. By setting the linear velocity at the time of filtration within the above range, it is possible to effectively suppress foreign matters and at the same time to effectively remove foreign matters and improve the throughput.

  A filtration process can be performed using the filtration apparatus 300 as shown in FIG. 1, for example. A filtration apparatus 300 shown in FIG. 1 includes a supply tank 210 for storing and supplying a semiconductor cleaning composition before removing foreign substances, a metering pump 220 for flowing the semiconductor cleaning composition before removing foreign substances at a constant flow rate, Filter 240 having a cartridge filter (not shown) and a housing in which this cartridge filter is housed (mounted), pulsation preventer 230 located in the middle of metering pump 220 and filter 240, pulsation preventer 230 and filter 240, and a second pressure gauge 270b disposed downstream of the filter 240. The first pressure gauge 270a is disposed between the first pressure gauge 270a and the second pressure gauge 270b. The filtering device 300 includes a return conduit 260 that returns the semiconductor cleaning composition from the filter 240 to the supply tank 210, and a discharge conduit 250 that discharges the semiconductor cleaning composition filtered by the filter 240. Yes.

  In the filtering device 300, the semiconductor cleaning composition before foreign matter removal is supplied from the supply tank 210 to the pulsation preventer 230 that has been pressurized by the metering pump 220. When there is a pulsation by the metering pump 220, the pulsation is reduced by the pulsation preventer 230. The semiconductor cleaning composition discharged from the pulsation preventer 230 is supplied to the filter 240 and removed through the discharge conduit 250 after removing foreign substances. Here, the “foreign matter” means particles having a particle diameter of 20 μm or more.

  The semiconductor cleaning composition recovered through the discharge conduit 5 is filled in a storage container to be described later. At this time, the linear velocity at the time of filling the container needs to be 11 to 150 L / min, and more preferably 13 to 130 L / min. By controlling the linear velocity within the above range, it is possible to suppress foaming and at the same time suppress contamination of foreign matter from the atmosphere and stabilize the quality of the semiconductor cleaning composition.

  If the removal of foreign matter in the semiconductor cleaning composition recovered through the discharge conduit 250 is not sufficient, the semiconductor cleaning composition is not discharged from the discharge conduit 250 and returned to the supply tank 210 through the return conduit 260; It can also filter with the filter 240 again. Moreover, when the pulsation by the metering pump 220 does not occur, the pulsation preventer 230 may not be arranged. Furthermore, when the viscosity of the semiconductor cleaning composition is high, the viscosity of the semiconductor cleaning composition can be lowered by heating the supply tank, the conduit, or both. That is, you may further provide the heating means which can heat a supply tank, a conduit | pipe, or both.

  In addition, although the filtration apparatus 300 is provided with the 1st pressure gauge 270a and the 2nd pressure gauge 270b, you may use the filtration apparatus which is not provided with a pressure gauge. However, by providing the first pressure gauge 270a and the second pressure gauge 270b, the differential pressure generated in the filter can be managed so that the filter functions normally. Moreover, it may replace with the supply tank 210 and may supply the composition for semiconductor cleaning before foreign material removal directly from the container for conveyance. And although the filtration apparatus 300 is an example using one filter 240, a several filter can also be used. When using a some filter, a some filter may be connected in series and you may arrange | position in parallel.

1.5. 2. Method for storing semiconductor cleaning composition The method for storing a semiconductor cleaning composition according to this embodiment (hereinafter also simply referred to as “storage method”) is a method of filling a container with the semiconductor cleaning composition for storage. The ratio of the volume of the void portion excluding the volume occupied by the semiconductor cleaning composition to the internal volume of the container is 5 to 20%, the oxygen concentration of the void portion is 0 to 5%, and is 5 ° C. or higher. It is characterized by storing at a temperature of 40 ° C. or lower. According to such a storage method, it was found that even a semiconductor cleaning composition to which no stabilizer or the like is added can suppress the occurrence of foreign matters and discoloration, and the storage stability is improved.

  The storage method according to this embodiment is applicable to any semiconductor cleaning composition, but can be suitably used for a semiconductor cleaning composition produced by the above-described method. That is, the storage method of the present invention is particularly effective when particles contained in the semiconductor cleaning composition tend to aggregate.

  In the storage method according to the present embodiment, it is essential to store the semiconductor cleaning composition at a temperature of 5 to 40 ° C., preferably 5 to 35 ° C. If the storage temperature exceeds the above range, the container tends to expand due to volatilization of water during long-term storage, and discoloration of the semiconductor cleaning composition tends to occur, so it cannot be stably stored. . When the storage temperature is less than the above range, particles present in the liquid tend to aggregate and generate a gel-like material or foreign matter, and cannot be stored stably.

  In the storage method according to the present embodiment, the ratio of the void volume excluding the volume occupied by the semiconductor cleaning composition to the internal volume of the container (%) ) (Hereinafter also referred to as “porosity”) is essential to be 5 to 20%, preferably 5 to 15%. When the porosity exceeds the above range, the volatilization of moisture when the storage temperature changes increases, and foreign matter is formed by drying the semiconductor cleaning composition at the gas-liquid interface and the container wall surface, so it can be stored stably. Can not do it. If the porosity is less than the above range, when the semiconductor cleaning composition undergoes a volume change due to a change in temperature, the container may be deformed or the container may be ruptured, so that it cannot be stably stored.

  In the storage method according to the present embodiment, it is essential that the oxygen concentration in the void is 0 to 5%, and the upper limit is preferably 4% or less, more preferably 3% or less, and even more. Preferably it is 2% or less, particularly preferably 1% or less. When the oxygen concentration in the void is within the above range, the generation of foreign matters and discoloration due to oxidation and / or alteration of the components contained in the semiconductor cleaning composition during long-term storage is effectively suppressed. can do.

  In the storage method according to this embodiment, the shape, material, and size of the container for storing the semiconductor cleaning composition are not particularly limited, but the elution concentration of metal ions in the semiconductor cleaning composition is 50 ppm or less. A container is preferred. When the metal ions are eluted into the semiconductor cleaning composition, the zeta potential balance on the particle surface dispersed in the composition is lost, so that aggregation of particles is likely to occur. The particles aggregated in this manner may cause contamination of the surface to be cleaned in the cleaning process of the surface to be cleaned, and may further damage the surface to be cleaned.

  In addition, as such a container with little metal elution, what was formed, for example with the material made from glass and resin is preferable. For example, a clean container produced by the method of JP-A-59-035043 can be preferably used.

  According to the storage method according to the present embodiment, the quality of the semiconductor cleaning composition hardly changes during storage even when the storage period is 6 months, preferably 12 months, and more preferably 18 months. Moreover, a gel-like thing is not produced. Therefore, the semiconductor cleaning composition after storage does not need to be filtered again, and can be subjected to the cleaning process of the surface to be cleaned under the same conditions as the semiconductor cleaning composition immediately after manufacture. Moreover, the effect which can improve the productivity of the composition for semiconductor cleaning becomes so large that a storage period becomes long in June, December, and 18 months.

2. Cleaning Agent The “cleaning agent” in the present invention refers to a liquid that is prepared by adding an aqueous medium to the above semiconductor cleaning composition and diluting it, and is used when actually cleaning the surface to be cleaned. Say. The above-described semiconductor cleaning composition usually exists in a state where each component is concentrated. Therefore, each user prepares a cleaning agent by appropriately diluting the above-described semiconductor cleaning composition with an aqueous medium, and uses the cleaning agent for use.

  The aqueous medium used for dilution here is synonymous with the aqueous medium contained in the above-described semiconductor cleaning composition, and includes water, a mixed medium of water and alcohol, and an organic solvent having compatibility with water and water. A mixed medium or the like can be used.

As a method for diluting an aqueous cleaning medium by adding an aqueous medium to the semiconductor cleaning composition, the pipe for supplying the semiconductor cleaning composition and the pipe for supplying the aqueous medium are joined together and mixed, and the mixed cleaning agent is mixed. There is a method of supplying the surface to be cleaned. This mixing is a method in which liquids collide with each other through a narrow passage with pressure applied; a method in which a filling such as a glass tube is filled in the pipe, and the liquid flow is separated and separated; A conventionally performed method such as a method of providing blades that rotate by power can be employed.

  Further, as another method of adding and diluting the aqueous cleaning medium to the semiconductor cleaning composition, a pipe for supplying the semiconductor cleaning composition and a pipe for supplying the aqueous medium are provided independently, and a predetermined amount of liquid is supplied from each. There is a method of supplying to the surface to be cleaned and mixing on the surface to be cleaned. Furthermore, as another method of adding an aqueous medium to a semiconductor cleaning composition and diluting, a predetermined amount of the semiconductor cleaning composition and the aqueous medium are mixed in one container, and then mixed on the surface to be cleaned. There is a method of supplying a semiconductor cleaning composition.

  As a dilution ratio when adding an aqueous medium to a semiconductor cleaning composition to dilute, 1 part by mass of the semiconductor cleaning composition is diluted to 1 to 500 parts by mass (1 to 500 times) by adding an aqueous medium. It is preferable to dilute to 20 to 500 parts by mass (20 to 500 times), and it is particularly preferable to dilute to 30 to 300 parts by mass (30 to 300 times). In addition, it is preferable to dilute with the same aqueous medium as the aqueous medium contained in the semiconductor cleaning composition described above. Thus, by making the composition for semiconductor cleaning into a concentrated state, it becomes possible to transport and store the cleaning agent in a smaller container as compared with the case of transporting and storing the cleaning agent as it is. As a result, transportation and storage costs can be reduced. In addition, since a smaller amount of the semiconductor cleaning composition is purified than when the cleaning agent is purified by filtration or the like, the purification time can be shortened, thereby enabling mass production. It becomes possible.

3. Cleaning Method A cleaning method according to an embodiment of the present invention includes copper or tungsten as a wiring material, and is selected from the group consisting of tantalum, titanium, cobalt, ruthenium, manganese, and a compound thereof as a barrier metal material. A step of cleaning a wiring substrate containing at least one type using a semiconductor cleaning composition (or a cleaning agent diluted with an aqueous medium, hereinafter referred to simply as “cleaning agent”) stored by the above-described method. including. Hereinafter, an example of the cleaning method according to the present embodiment will be described in detail with reference to the drawings.

<Production of wiring board>
FIG. 2 is a cross-sectional view schematically showing a manufacturing process of a wiring board used in the cleaning method according to this embodiment. Such a wiring board is formed through the following process.

  FIG. 2 is a cross-sectional view schematically showing an object to be processed before the CMP process. As shown in FIG. 2, the target object 100 has a base 10. The substrate 10 may be composed of, for example, a silicon substrate and a silicon oxide film formed thereon. Further, although not shown in the figure, a functional device such as a transistor may be formed on the base 10.

  An object 100 to be processed includes an insulating film 12 provided with a wiring recess 20 on a substrate 10, and a barrier metal film provided so as to cover the surface of the insulating film 12 and the bottom and inner wall surfaces of the wiring recess 20. 14 and a metal film 16 filling the wiring recess 20 and formed on the barrier metal film 14 are sequentially laminated.

  As the insulating film 12, for example, a silicon oxide film (for example, a PETEOS film (Plasma Enhanced-TEOS film), a HDP film (High Density Plasma Enhanced-TEOS film)) formed by a vacuum process, or a thermal chemical vapor deposition method is used. And an insulating film called FSG (Fluorine-doped silicate glass), a boron phosphorous silicate film (BPSG film), an insulating film called SiON (Silicon Oxide Nitride), and silicon nitride.

  Examples of the barrier metal film 14 include tantalum, titanium, cobalt, ruthenium, manganese, and compounds thereof. The barrier metal film 14 is often formed from one of these, but two or more types such as tantalum and tantalum nitride can be used in combination.

  As shown in FIG. 2, the metal film 16 needs to completely fill the recess 20 for wiring. For this purpose, a metal film of 10,000 to 15000 mm is usually deposited by chemical vapor deposition or electroplating. Examples of the material for the metal film 16 include copper or tungsten. In the case of copper, not only high-purity copper but also an alloy containing copper can be used. The copper content in the alloy containing copper is preferably 95% by mass or more.

  Next, in the object 100 of FIG. 2, the metal film 16 other than the portion buried in the wiring recess 20 is polished at high speed by CMP until the barrier metal film 14 is exposed (first polishing process). Further, the barrier metal film 14 exposed on the surface is polished by CMP (second polishing step). In this way, a wiring board 200 as shown in FIG. 3 is obtained.

<Washing of wiring board>
Next, the surface (surface to be cleaned) of the wiring substrate 200 shown in FIG. 3 is cleaned using the above-described cleaning agent. According to the cleaning method according to the present embodiment, when cleaning the wiring board on which the wiring material and the barrier metal material after CMP are coexisted on the surface, corrosion of the wiring material and the barrier metal material is suppressed, and The oxide film and organic residue can be efficiently removed.

  The cleaning method according to this embodiment includes tungsten as a wiring material of a wiring board, and the wiring board is a composition containing iron ions and a peroxide described in JP-A-10-265766 (Fenton reagent). It is very effective when it is performed after chemical mechanical polishing using In CMP of an object to be polished having tungsten as a wiring material, a CMP slurry containing iron ions and peroxides (hydrogen peroxide, potassium iodate, etc.) is used. Since iron ions contained in the CMP slurry are easily adsorbed on the surface of the object to be polished, the surface of the object to be polished is easily contaminated with iron. In this case, iron contamination can be removed by washing the surface of the object to be polished with dilute hydrofluoric acid, but the surface of the object to be polished is etched and easily damaged. However, when the semiconductor cleaning composition described above contains specific particles in a predetermined ratio, it is considered that the specific particles can effectively remove iron contamination on the surface to be polished. Moreover, when the above-mentioned composition for semiconductor cleaning contains potassium and sodium at a predetermined ratio, the formation of a readily soluble salt such as potassium tungstate or sodium tungstate is promoted in the cleaning step. Thereby, it is considered that metal contamination on the wiring substrate can be reduced, and polishing residues can be efficiently removed while reducing damage to the object to be polished.

  Although it does not restrict | limit especially as a cleaning method, It is performed by the method of making the above-mentioned cleaning agent contact the wiring board 200 directly. As a method of bringing the cleaning agent into direct contact with the wiring substrate 200, a dip method in which a cleaning tank is filled with the cleaning agent and the wiring substrate is immersed; a spin method in which the wiring substrate is rotated at a high speed while flowing the cleaning agent from the nozzle onto the wiring substrate. A spray type method of cleaning the wiring board by spraying a cleaning agent. In addition, as an apparatus for performing such a method, a batch type cleaning apparatus that simultaneously cleans a plurality of wiring boards accommodated in a cassette, a single wafer cleaning that attaches and cleans one wiring board to a holder Examples thereof include an apparatus.

  In the cleaning method according to the present embodiment, the temperature of the cleaning agent is usually room temperature, but may be heated within a range that does not impair the performance, and can be heated to, for example, about 40 to 70 ° C.

In addition to the above-described method of bringing the cleaning agent into direct contact with the wiring substrate 200, it is also preferable to use a cleaning method using physical force. Thereby, the removal property of the contamination by the particles adhering to the wiring board 200 is improved, and the cleaning time can be shortened. Examples of the cleaning method using physical force include scrub cleaning using a cleaning brush and ultrasonic cleaning.

  Furthermore, cleaning with ultrapure water or pure water may be performed before and / or after cleaning by the cleaning method according to the present embodiment.

4). Examples Hereinafter, the present invention will be described by way of examples. However, the present invention is not limited to these examples. In the examples, “parts” and “%” are based on mass unless otherwise specified.

4.1. Example 1
4.1.1. Preparation of Semiconductor Cleaning Composition Each component was added to a polyethylene container so as to have the content shown in Table 1, and an appropriate amount of ion-exchanged water was added and stirred for 15 minutes. To this mixture, ion-exchanged water, potassium hydroxide and sodium hydroxide are added so that the total amount of all the constituent components is 100 parts by mass, and the composition is such that the pH, K content and Na content shown in Table 1 are obtained. I adjusted things.

  After adding 0.01 parts by mass of colloidal silica (trade name “PL-1”, manufactured by Fuso Chemical Industries, Ltd., primary particle size: 15 nm) to the composition thus obtained, the filtration shown in FIG. Filtration was performed using the apparatus 300 (filtration process). A filtration apparatus 300 shown in FIG. 1 includes a supply tank 210 for storing and supplying a composition before removing foreign substances, a metering pump 220 for flowing the composition before removing foreign substances at a constant flow rate, and a cartridge filter (not shown). ) And a filter 240 having a housing in which this cartridge filter is housed (mounted), a pulsation preventer 230 located in the middle of the metering pump 220 and the filter 240, and disposed between the pulsation preventer 230 and the filter 240. The first pressure gauge 270a and the second pressure gauge 270b arranged downstream of the filter 240 are provided. The filtering device 300 includes a return conduit 260 that returns the semiconductor cleaning composition from the filter 240 to the supply tank 210, and a discharge conduit 250 that discharges the semiconductor cleaning composition filtered by the filter 240. Yes.

  In this embodiment, the filter 240 has a membrane type cartridge filter “Water Fine” (manufactured by Nippon Pole Co., Ltd., rated filtration accuracy 0.05 μm, length 10 inches) mounted in the housing. The metering pump 220 was an air-driven diaphragm pump, and the differential pressure before and after the filter was 0.2 to 0.3 MPaG, and the flow rate of the composition was the linear velocity shown in Table 1.

  When the composition was sampled in a timely manner, the filtration was stopped when the number of particles of 0.1 to 0.3 μm contained in the composition reached the concentration shown in Table 1, and the semiconductor cleaning composition of Example 1 A product was prepared. The number of particles per 1 mL of the composition was measured as follows.

  As the particle counter, an in-liquid particle sensor “KS-42AF” manufactured by Rion Co., Ltd. was used. Specifically, first, the number of particles to be measured is “300 particles / mL (0.1 μm)” (that is, “300 particles having a particle diameter larger than 0.1 μm in 1 mL or less”). The blank measurement was repeated with ultrapure water. Thereafter, 100 mL of a semiconductor cleaning composition (sample) was prepared, and this sample was set in a syringe sampler “KZ-31W”. Thereafter, the number of particles having a particle diameter of 0.1 to 0.3 μm per 1 mL of the sample is measured twice by the particle sensor in liquid, and an average value is calculated. This average value was defined as the number of particles having a particle diameter of 0.1 to 0.3 μm per 1 mL of the semiconductor cleaning composition.

4.1.2. Wiring board cleaning test (1) Chemical mechanical polishing step Copper wiring patterned substrate (PETOS film was deposited on a silicon substrate having a diameter of 8 inches with a thickness of 5000 mm and then patterned with a “SEMATECH 854” mask. A test substrate in which a cobalt film with a thickness of 250 mm, a copper seed film with a thickness of 1000 mm, and a copper plating film with a thickness of 10,000 mm is sequentially laminated on the chemical mechanical polishing apparatus “EPO112” manufactured by Ebara Manufacturing Co., Ltd. The two-stage chemical mechanical polishing was carried out under the following conditions. In the first-stage chemical mechanical polishing, the copper seed film and the copper plating film were chemically mechanically polished until the cobalt film was exposed. In the second-stage chemical mechanical polishing, the cobalt film, the copper seed film, and the copper plating film were chemically mechanically polished until the PETEOS film was exposed.

<First stage chemical mechanical polishing>
-Chemical mechanical polishing aqueous dispersion: "CMS7501 / CMS7552" manufactured by JSR Corporation
・ Polishing pad: “IC1000 / SUBA400” manufactured by Rodel Nitta Co., Ltd.
・ Surface rotation speed: 70rpm
-Head rotation speed: 71 rpm
-Head load: 50 g / cm ²
-Chemical mechanical polishing aqueous dispersion supply rate: 200 mL / min-Polishing time: 150 seconds

<Second stage chemical mechanical polishing>
-Chemical mechanical polishing aqueous dispersion: "CMS8501 / CMS8552" manufactured by JSR Corporation
・ Polishing pad: “IC1000 / SUBA400” manufactured by Rodel Nitta Co., Ltd.
・ Surface rotation speed: 70rpm
-Head rotation speed: 71 rpm
Head load: 250 g / cm ²
-Chemical mechanical polishing aqueous dispersion supply rate: 200 mL / min-Polishing time: 60 seconds

(2) Washing process The polished substrate surface obtained above is treated with ultrapure water (with a particle size of 0.3 μm or more so as to have the dilution ratio shown in Table 1 in the semiconductor cleaning composition obtained above. A cleaning agent was prepared by adding and diluting 10 particles / mL or less, pH = 6.5), and was subjected to cleaning on a platen under the following conditions. Thereafter, it was similarly subjected to brush scrub cleaning.

<Washing on the surface plate>
-Cleaning agent: Cleaning agent prepared above-Head rotation speed: 71 rpm
Head load: 100 g / cm ²
・ Surface rotation speed: 70rpm
・ Cleaning agent supply speed: 300 mL / min ・ Cleaning time: 30 seconds

<Brush scrub cleaning>
-Cleaning agent: Cleaning agent prepared above-Upper brush rotation speed: 100 rpm
・ Lower brush rotation speed: 100rpm
-Substrate rotation speed: 100 rpm
-Cleaning agent supply amount: 300 mL / min-Cleaning time: 30 seconds

4.1.3. Evaluation test <Corrosion evaluation>
Using the scanning electron microscope (manufactured by Hitachi High-Technologies, model number “S-4800”), the surface of the washed substrate obtained above was subjected to a test pattern 0.175 μm copper wiring portion at a magnification of 120,000 times. The corrosion was evaluated by observing. The results are shown in Table 1. The evaluation criteria are as follows.
(Evaluation criteria)
The number of copper wires in which corrosion in 10 copper wires was observed was
・ If it is 3 or less and no slit is recognized between the barrier metal, it is judged as very good and “◎”
・ If it is more than 3 and less than 5 and no slit is recognized between the barrier metal and the barrier metal, it is judged that it can be used, and “○”.
・ If there are more than 5 or a slit is found between the barrier metal and the barrier metal, it is judged as defective and "X"
It was written.

<Defect evaluation>
The number of defects on the entire surface to be polished was measured using a wafer defect inspection apparatus (model number “KLA2351” manufactured by KLA-Tencor Corporation) on the substrate surface after cleaning obtained above. The results are shown in Table 1. The evaluation criteria are as follows.
(Evaluation criteria)
The number of defects on the entire substrate surface is
・ If it is 250 or less, it is judged to be very good and “◎”
・ If it is over 250 and 500 or less, it is judged as usable and “○”
・ If the number is 500 or more, it is judged as defective and "X"
It was written.

<Reliability evaluation>
The second stage chemical mechanical polishing substrate (a test substrate having a copper film laminated with a thickness of 5000 mm) was washed by running with the above scrubbing cleaning using the cleaning agent obtained above. did. The substrate after cleaning was inspected for defects, and a case where the number of defects on the entire substrate surface was more than 250 was regarded as defective. The reliability of the cleaning agent was evaluated by counting the number of substrates that were defective in 1000 sheets. The results are shown in Table 1. The evaluation criteria are as follows.
(Evaluation criteria)
The number of substrates that were defective in 1000
・ If it is 50 sheets or less, it is judged as very good and “◎”
・ If it is more than 50 and less than 100, it is judged that it can be used.
・ If there are more than 100 sheets, it is judged as bad and “×”

<Storage stability evaluation>
The semiconductor cleaning composition is injected into the storage container at the linear velocity shown in Table 1, and the ratio to the internal volume of the container (void ratio), the storage temperature, and the oxygen concentration in the gas remaining in the container are the conditions described in Table 1. And stored for 6 months. The oxygen concentration was adjusted by transferring the semiconductor cleaning composition to a storage container and then replacing it by blowing high-purity nitrogen into the container. Table 1 shows the results of visual judgment of the presence or absence of foreign matter and the appearance of the storage container of the semiconductor cleaning composition after storage for 6 months. The evaluation criteria are as follows.
(Evaluation criteria-presence or absence of foreign matter)
In the storage container after 6 months storage,
・ If no foreign matter (precipitate) can be confirmed by visual inspection and no discoloration is observed compared to before storage, it is judged as good and “Good”.
・ If foreign matter (sediment) can be visually confirmed, or if discoloration is observed compared to before storage, it is judged to be defective and "X"
(Evaluation criteria-appearance of storage container)
In storage containers after 6 months storage
・ If there is no change in the appearance of the storage container by visual inspection, it is judged as good and “○”
・ If there is a change in the appearance of the storage container by visual inspection, it is judged to be defective and "X"

  In Tables 1 to 3, “CB” represents a clean bottle, and a 20 liter square can type clean bottle commercially available from Aicello Co., Ltd. was used. “PL” represents a washed plastic container, and a commercially available 20-liter square can-type polypropylene container was washed in a clean room. “ME” represents a metal can, and a commercially available metal funnel can was used.

4.2. Examples 2-26 and Comparative Examples 1-12
The wiring board cleaning test and evaluation were performed in the same manner as in Example 1 except that the semiconductor cleaning composition was changed to the compositions shown in Tables 1 and 2 and the cleaning agents having the compositions shown in Tables 1 and 2 were used. A test was conducted.

4.3. Example 27
4.3.1. Preparation of semiconductor cleaning composition The composition was changed to the composition shown in Table 3, and adjusted to the pH, K content, and Na content shown in Table 3 using potassium hydroxide and sodium hydroxide as necessary. Except for the above, a semiconductor cleaning composition was prepared in the same manner as in Example 1.

4.3.2. Wiring board cleaning test (1) Chemical mechanical polishing step Copper wiring patterned substrate (PETOS film was deposited on a silicon substrate having a diameter of 8 inches with a thickness of 5000 mm and then patterned with a “SEMATECH 854” mask. A chemical substrate polishing apparatus “EPO112” manufactured by Ebara Manufacturing Co., Ltd. was prepared by laminating a cobalt film having a thickness of 250 mm, a tungsten seed film having a thickness of 1000 mm, and a tungsten plating film having a thickness of 10,000 mm. The single-stage chemical mechanical polishing was carried out under the following conditions.

<Polishing conditions>
・ Aqueous dispersion for chemical mechanical polishing: Cabot Corporation, “W2000” (slurry containing iron ions and hydrogen peroxide)
・ Polishing pad: “IC1000 / SUBA400” manufactured by Rodel Nitta Co., Ltd.
・ Surface rotation speed: 70rpm
-Head rotation speed: 71 rpm
-Head load: 50 g / cm ²
-Chemical mechanical polishing aqueous dispersion supply rate: 200 mL / min-Polishing time: 150 seconds

(2) Cleaning process The polished substrate surface obtained above is ultrapure water (with a particle size of 0.3 μm or more so as to have the dilution ratio shown in Table 3 in the semiconductor cleaning composition obtained above. A cleaning agent was prepared by adding and diluting 10 particles / mL or less, pH = 6.5), and was subjected to cleaning on a platen under the following conditions. Thereafter, it was similarly subjected to brush scrub cleaning.

<Washing on the surface plate>
-Cleaning agent: Cleaning agent prepared above-Head rotation speed: 71 rpm
Head load: 100 g / cm ²
・ Surface rotation speed: 70rpm
・ Cleaning agent supply speed: 300 mL / min ・ Cleaning time: 30 seconds

<Brush scrub cleaning>
-Cleaning agent: Cleaning agent prepared above-Upper brush rotation speed: 100 rpm
・ Lower brush rotation speed: 100rpm
-Substrate rotation speed: 100 rpm
-Cleaning agent supply amount: 300 mL / min-Cleaning time: 30 seconds

4.3.3. Evaluation test <Corrosion evaluation>
The substrate surface after cleaning obtained above was evaluated in the same manner as in Example 1. The results are shown in Table 3.

<Defect evaluation>
The substrate surface after cleaning obtained above was evaluated in the same manner as in Example 1. The results are shown in Table 3.

<Reliability evaluation>
1000 substrates subjected to the above chemical mechanical polishing (a test substrate having a tungsten film laminated with a thickness of 3000 mm) were washed by running by the brush scrub cleaning using the cleaning agent obtained above. The substrate after cleaning was inspected for defects, and a case where the number of defects on the entire substrate surface was more than 250 was regarded as defective. The reliability of the cleaning agent was evaluated by counting the number of substrates that were defective in 1000 sheets. The results are shown in Table 3. The evaluation criteria are as follows.
(Evaluation criteria)
The number of substrates that were defective in 1000
・ If it is 50 sheets or less, it is judged as very good and “◎”
・ If it is more than 50 and less than 100, it is judged that it can be used.
・ If there are more than 100 sheets, it is judged as bad and “×”

<Storage stability evaluation>
Evaluation was performed in the same manner as the storage stability evaluation in the above "4.1.3. Evaluation test". The results are shown in Table 3.

4.4. Examples 28-31 and Comparative Examples 13-15
A wiring board cleaning test and an evaluation test were performed in the same manner as in Example 27 except that the composition for cleaning the semiconductor was changed to the composition shown in Table 3 and the cleaning composition having the composition shown in Table 3 was used.

4.5. Evaluation results Tables 1 to 3 below show the compositions and evaluation results of the semiconductor cleaning compositions.

In the above Tables 1 to 3, the numerical value of each component represents parts by mass. In each example and each comparative example, the total amount of each component is 100 parts by mass, and the balance is ion-exchanged water. Moreover, it supplements about the following component in the above Tables 1-3.
Polyacrylic acid (Mw = 700,000): manufactured by Toa Gosei Co., Ltd., trade name “Julimer AC-10H”
Polyacrylic acid (Mw = 55,000): manufactured by Toa Gosei Co., Ltd., trade name “Jurimer AC-10L”
Polyacrylic acid (Mw = 6,000): manufactured by Toa Gosei Co., Ltd., trade name “Aron A-10SL”
Polymaleic acid (Mw = 2,000): NOF Corporation, trade name “Non-Pole PWA-50W”
Polyallylamine (Mw = 25,000): Product name “PAA-25” manufactured by Nitto Bo Medical Co., Ltd.
-Polyallylamine (Mw = 15,000): Product name “PAA-15” manufactured by Nitto Bo Medical Co., Ltd.
Polystyrene sulfonic acid (Mw = 50,000): Tosoh Organic Chemical Co., Ltd., trade name “PS-5H”
Styrene-maleic acid copolymer: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name “DKS DISCOAT N-10”
Styrene-maleic acid half ester copolymer: manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name “DKS DISCOAT N-14”
-Naphthalenesulfonic acid formalin condensate Na salt: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name "Labelin FD-40"
Polyvinyl alcohol (Mw = 26,000): Kuraray Co., Ltd., trade name “PVA405”
・ Polyethyleneimine (Mw = 70,000): Nippon Shokubai Co., Ltd., trade name “Epomin P-1000”

  As apparent from Tables 1 to 3 above, according to the method for storing a semiconductor cleaning composition according to the present invention, the occurrence of foreign matter and discoloration of the semiconductor cleaning composition was observed even after storage for 6 months. In addition, no change was observed in the appearance of the storage container.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the present invention includes substantially the same configuration (for example, a configuration having the same function, method, and result, or a configuration having the same purpose and effect) as the configuration described in the embodiment. In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. In addition, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

DESCRIPTION OF SYMBOLS 10 ... Base | substrate, 12 ... Insulating film, 14 ... Barrier metal film, 16 ... Metal film, 20 ... Recess for wiring, 100 ... To-be-processed object, 200 ... Wiring board, 210 ... Supply tank, 220 ... Metering pump, 230 ... Pulsation Preventer, 240 ... filter, 250 ... discharge conduit, 260 ... return conduit, 270a ... first pressure gauge, 270b ... second pressure gauge, 300 ... filtering device

Claims (10)

A method of storing a semiconductor cleaning composition by filling the container,
When the semiconductor cleaning composition contains potassium and sodium, the content of potassium is M _K (ppm) and the content of sodium is M _Na (ppm), M _Na = 1 × 10 ⁻⁶ 10 × 10 ⁰ (ppm) and M _K / M _Na = 5 × 10 ³ to 1 × 10 ⁵ ,
The ratio of the volume of the void portion excluding the volume occupied by the semiconductor cleaning composition to the internal volume of the container is 5 to 20%,
By blowing and replacing with nitrogen, the oxygen concentration of the voids is 0 to 5%,
A method for storing a composition for cleaning a semiconductor, comprising storing at a temperature of 5 ° C. or higher and 40 ° C. or lower.   The storage method according to claim 1, wherein the semiconductor cleaning composition is filtered through a depth-type or pleat-type filtration filter.   The storage method according to claim 2, wherein the filtration accuracy of the filtration filter is 0.01 to 20 μm. The semiconductor cleaning composition contains 3 × ¹⁰ 1 to 1.5 × 10 ³ cells / mL particles 0.1 to 0.3 [mu] m, according to any one of claims 1 to 3 Storage method. A method of storing a semiconductor cleaning composition by filling the container,
When the semiconductor cleaning composition contains potassium and sodium, the potassium content is M _K (ppm), and the sodium content is M _Na (ppm), M _Na = 1.0 × 10 ⁻⁶ to 10 × 10 ⁰ , and M _K / M _Na = 5 × 10 ³ to 1 × 10 ⁵ ,
The ratio of the volume of the void portion excluding the volume occupied by the semiconductor cleaning composition to the internal volume of the container is 5 to 20%,
The oxygen concentration in the void is 0 to 5%,
A method for storing a composition for cleaning a semiconductor, comprising storing at a temperature of 5 ° C. or higher and 40 ° C. or lower. The storage method according to any one of claims 1 to 5 , wherein the semiconductor cleaning composition contains an organic acid. The semiconductor cleaning composition containing a water-soluble polymer, storage method according to any one of claims 1 to 6. The storage method according to any one of claims 1 to 7 , wherein the semiconductor cleaning composition is used after being diluted 1 to 500 times. A wiring board containing copper or tungsten as a wiring material and at least one selected from the group consisting of tantalum, titanium, cobalt, ruthenium, manganese, and a compound thereof as a barrier metal material. A cleaning method comprising a step of cleaning using the semiconductor cleaning composition stored by the storage method according to any one of Items 8 . The storage method according to any one of claims 1 to 8 , wherein tungsten is contained as a wiring material of the wiring board, and the wiring board is subjected to chemical mechanical polishing using a composition containing iron ions and a peroxide. The washing | cleaning method including the process of wash | cleaning using the composition for semiconductor washing | cleaning preserve | saved by.

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