Alkaline composition, its use, and method for cleaning substrates containing cobalt and copper.

Abstract

The present invention relates to an alkaline composition for cleaning a substrate comprising i) copper or a copper alloy and ii) cobalt or a cobalt alloy, the composition comprising: a) at least one pH adjuster selected from compounds of formula I 【Chemical 1】 TIFF2026524618000015.tif3368(where Ra, Rb, Rd and Rf are each independently selected from unsubstituted linear or branched C1-C 12 alkyl, Re is selected from unsubstituted linear or branched C4-C9 alkyl; provided that the dashed bond between Re and N is a single bond or a double bond, and when the dashed bond is a double bond, Rd does not exist, Ra, Rb, Re and Rf are joined to form one or more 6-membered or 7-membered rings), b) at least one complexing agent selected from C2-C 12 hydrocarbons having at least two sulfonic acid groups or carboxylic acid groups, c) at least one polymeric dispersant having a mass average molecular weight of 1000 g / mol or more; and d) a solvent containing water and comprising.

Description

[Technical Field]

[0001] The present invention relates to an alkaline composition, its use, and a method for cleaning a substrate containing copper or a copper alloy and cobalt or a cobalt alloy. [Background technology]

[0002] The manufacture of electrical equipment, particularly semiconductor integrated circuits (ICs); liquid crystal panels; organic electroluminescent panels; printed circuit boards; micromachines; DNA chips; microplants and magnetic heads; preferably ICs equipped with LSIs (large-scale integrated circuits) or VLSIs (very large-scale integrated circuits); and optical devices, particularly optical glass, e.g., photomasks, lenses and prisms; inorganic conductive films, e.g., indium tin oxide (ITO); optical integrated circuits; optical switching elements; optical waveguides; optical single crystals, e.g., optical fiber end faces and scintillators; solid-state laser single crystals; sapphire substrates for blue laser LEDs; semiconductor single crystals; and glass substrates for magnetic disks requires high-precision methods, which in particular include surface treatment, pre-plating cleaning, post-etching cleaning, and / or post-chemical polishing cleaning steps, which are carried out using high-purity cleaning compositions.

[0003] Particular care is required in the manufacturing of ICs incorporating LSIs or VLSIs. The semiconductor wafers used for this purpose contain a semiconductor substrate, such as silicon, with patterned areas for depositing different materials possessing electrical insulating, conductive, or semiconductor properties. To achieve correct pattern formation, excess material used in forming the various layers on the substrate must be removed. Furthermore, planarizing the semiconductor wafer surface is crucial for manufacturing functional and reliable ICs. Therefore, in IC manufacturing, specific surfaces of the semiconductor wafer must be cleaned, removed, and / or polished before proceeding to the next process step.

[0004] Most processing steps, including wafer surface preparation, deposition, plating, etching, and chemical mechanical planarization (CMP), require cleaning operations to remove contaminants that could impair or prevent the IC from performing its intended function.

[0005] For example, problems can arise from residues remaining on the substrate after CMP (Chemical Polishing). In Cu-CMP, for instance, the copper ion concentration can exceed the maximum solubility of the copper inhibitor complex. This can cause the copper inhibitor complex to precipitate from the solution and aggregate as residue on the surface. Furthermore, these residues can adhere to and accumulate on the surface of the polishing pad, eventually filling the grooves of the pad. In addition, polishing particles and chemicals contained in the CMP slurry, as well as reaction byproducts, can cause serious damage if they remain on the wafer surface. Moreover, polishing copper Damascus structures containing low-k or ultra-low-k dielectric materials, such as carbon-doped oxides or organic films, can generate carbon-rich particles that deposit on the wafer surface. Further complicating matters is the fact that these low-k or ultra-low-k dielectric materials, and the silicon carbide, silicon nitride, or silicon oxynitride CMP stop layers, are extremely hydrophobic, making them difficult to clean with water-based cleaning solutions.

[0006] Another residue-generating process common to IC manufacturing is gas-phase plasma etching, which transfers the pattern (for via and trench formation) of the exposed photoresist coating to the underlying layers (hard mask, interlayer insulator, etching stop layer, etc.). Residue after gas-phase plasma etching contains chemical elements present on the surface, within, and in the plasma gas of the substrate, and typically deposits on the back-end-of-line (BEOL) structure. If not removed, it can interfere with subsequent silicification and contact formation.

[0007] Recent advances in wafer processing and manufacturing technologies have led to the adoption of new materials, particularly metals and metal alloys, in the manufacturing of microelectronic devices. For example, in integrated circuits, conventional barrier layer materials are being replaced with cobalt (Co) and cobalt alloys to reduce layer thickness and circuit size. Another approach involves using cobalt as a new plug material in integrated circuits. As these new cobalt-containing layers or cobalt alloy layers and plugs are introduced, the industry is seeing increased demand for post-CMP removal / cleaning compositions that can remove post-CMP residues and contaminants (including the aforementioned precipitation corrosion inhibitors) without adversely affecting the new cobalt layer materials.

[0008] Furthermore, if the substrate involves metallization based on, for example, cobalt and copper (e.g., the Co-liner integration scheme described in US2012 / 0161320) and these surfaces may come into contact with the cleaning solution, care must be taken to ensure that the cleaning solution is compatible with both metals. This is particularly evident in Cu-PCC and PERR solutions. In PERR, the metallic structure is only exposed at the bottom of vias etched into the dielectric layer. However, in post-Cu CMP, the top surface of the metallization is completely exposed to the PCC solution. Galvanic corrosion may also need to be considered, as metallic or metallic conductive materials are in galvanic contact (Co-liner integration scheme) and immersed in the PERR or PCC cleaning solution. Examples of metals involved include Ru, Pt, Co, Ir, Pd, Re, Rh, Ti, Ta, Mn, Ni, Al, Cr, V, Mo, Zr, Nb, W, Cu, their alloys, and conductive materials such as TiN and TaN. Additionally, Cu may be used as a filler.

[0009] US 2018 / 0371371 A1 and US 2019 / 002802 A1 disclose aqueous post-CMP cleaning compositions comprising polyethylene glycol, anionic polymers such as polyacrylic acid, acrylic acid-maleic acid copolymer, polyaspartic acid, polyglutamic acid, polyvinylphosphonic acid, polyvinyl sulfonic acid, poly(styrene sulfonic acid), polycarboxylate ether, polyphosphate, and copolymers of these polymers. Meanwhile, US 10351809 B2 discloses cleaning compositions and methods for cleaning residues and contaminants from microelectronic devices after chemical mechanical polishing (CMP), comprising at least one organic amine, at least one solvent, at least one quaternary base, at least one complexing agent, at least one reducing agent, optionally at least one additional etching agent, and optionally at least one cleaning additive, wherein the cleaning compositions are essentially free of alkali hydroxides, alkaline earth metal hydroxides, and tetramethylammonium hydroxide. The compositions described are particularly intended for cleaning substrates containing cobalt. [Prior art documents] [Patent Documents]

[0010] [Patent Document 1] US2012 / 0161320 [Patent Document 2] US 2018 / 0371371 A1 [Patent Document 3] US 2019 / 002802 A1 [Patent Document 4] US 10351809 B2 [Overview of the project] [Problems that the invention aims to solve]

[0011] However, despite these advancements, the preparation of suitable compositions is often difficult. Additional barriers often encountered include the immiscibility or low solubility of various components, which renders the composition unsuitable for manufacture in concentrated form. This reduces their processability and economy. Thus, there remains an unsolved problem of further providing improved cleaning compositions.

Means for Solving the Problems

[0012] Surprisingly, the composition of the present invention described below has been found to not only enable high processability but also suppress the etching rates of cobalt and copper to an astonishingly low level.

[0013] Thus, in one aspect, the present invention relates to an alkaline composition for cleaning a substrate comprising i) copper or a copper alloy, and ii) cobalt or a cobalt alloy, the composition comprising: a) at least one pH adjuster selected from the compounds of Formula I

Chemical formula

[0014] In another embodiment, the present invention relates to a concentrate for preparing the compositions described herein, wherein the concentrate is: a) At least one pH adjusting agent in an amount of 4.0 to 40.0% by mass; b) At least one complexing agent in an amount of 0.1 to 3.0 mass%, c) At least one polymer dispersant in an amount of 0.01 to 3.0% by mass; and d) The remaining water-containing solvent including, In another embodiment, the present invention relates to a substrate comprising (i) a surface of cobalt or a cobalt alloy, and (ii) a surface of copper or a copper alloy, (a) Post-etching residue (PERR) or post-ashing residue (PARR), (b) Chemical mechanical planarization (CMP) residue This relates to a method of using the compositions described herein for removing [unclear].

[0015] In another embodiment, the present invention relates to a method for processing a microelectronic device with a composition for a time and temperature effective in at least partially, preferably completely, removing post-etching residue, post-ashing residue, or chemomechanical planarization (CMP) residue from a substrate, wherein the method is as follows: (a) A process to provide a microelectronic substrate having etching residue, ashing residue, or chemical mechanical planarization (CMP) residue thereon, and including (i) a surface of cobalt or a cobalt alloy, and (ii) a surface of copper or a copper alloy; (b) A step of providing the compositions described herein; and (c) A step of bringing the composition into contact with (i) the surface of cobalt or a cobalt alloy and (ii) the surface of copper or a copper alloy for a time and temperature effective in removing at least partially, preferably completely, the post-etching residue, post-ash residue, or chemomechanical planarization (CMP) residue from the substrate. Includes.

[0016] In another embodiment, the present invention relates to a method for manufacturing a semiconductor device, comprising the process described herein.

[0017] This invention relates to at least one of the following objectives: (1) The composition can substantially and efficiently remove CMP residues and contaminants from substrates containing or made of cobalt or cobalt alloys (e.g., cobalt as part of a layer or as a plug) in particular, without adversely affecting electrical materials and devices, in particular semiconductor integrated circuits, while providing a high-quality surface finish.

[0018] (2) The compositions and methods of the present invention aim to improve the etching suppression performance of both copper and cobalt.

[0019] (3) The composition of the present invention aims to provide a stable formulation that does not undergo precipitation or phase separation, particularly in the alkaline range.

[0020] (4) The present invention aims to provide a composition that is easy to process, economically feasible, easy to use, and environmentally friendly. [Modes for carrying out the invention]

[0021] The following detailed description is illustrative only and is not intended to limit the invention or its applications and uses. Furthermore, it is not intended to be bound by any prior art, background, overview, or theories presented in the following detailed description.

[0022] As used herein, the terms “include,” “contain,” and “compose” are synonymous with “include,” “contain,” “include,” and “contain,” and are inclusive or open, not excluding any additional, undescribed components, elements, or methods or processes. It should be understood that as used herein, the terms “include,” “contain,” and “compose” include the terms “consist of,” “become,” and “be comprised of.”

[0023] Furthermore, terms such as "(a)", "(b)", "(c)", and "(d)" in the specification and claims are used to distinguish similar elements and do not necessarily describe a sequential or chronological order. These terms are interchangeable under appropriate circumstances, and it should be understood that embodiments of the invention described herein may operate in an order other than that described or illustrated herein. Where terms such as "(A)", "(B)", "(C)" or "(a)", "(b)", "(c)", "(d)", "(i)", and "(ii)" relate to methods, methods of use, or steps of an assay, there is no temporal or temporal interval consistency between steps. That is, steps may be performed simultaneously, or there may be time intervals of seconds, minutes, hours, days, weeks, months, or years between steps unless otherwise stated in the above or below application documents.

[0024] The following paragraphs define different aspects of the present invention in more detail. Each of the aspects defined in this manner may be combined with any other aspect or more of the aspects unless expressly opposed. In particular, features indicated as preferred or advantageous may be combined with any other feature or features indicated as preferred or advantageous.

[0025] Throughout this specification, any reference to “one embodiment,” “an embodiment,” or “a preferred embodiment” means that a particular function, structure, or characteristic described in relation to that embodiment is included in at least one embodiment of the present invention. Therefore, expressions such as “in one embodiment,” “in an embodiment,” or “in a preferred embodiment” appearing in various places throughout this specification may, but may not, refer to the same embodiment. Furthermore, as will be apparent to those skilled in the art from this disclosure, features, structures, and characteristics can be combined in any suitable way in one or more embodiments. Also, some embodiments described herein may include some features included in other embodiments but not others, but combinations of features from different embodiments are, as those skilled in the art will understand, within the scope of the subject matter and constitute different embodiments. For example, any embodiment described in any claim, or any combination thereof, may be used in the appended claims.

[0026] Furthermore, the range defined throughout the specification includes the extreme values; that is, the range 1 to 10 means that both 1 and 10 are included in the range. To avoid any doubt, the applicant has rights to any equivalent under applicable law.

[0027] For the purposes of this invention, "mass%" or "wt.%" as used herein refers to the total mass of the coating composition. Furthermore, the sum of the mass%s of all compounds in each component described later is 100% by mass.

[0028] For the purposes of this invention, a substrate is defined as a semiconductor wafer made from silicon or a similar metallometal used in the manufacture of microelectronic devices.

[0029] For the purposes of this invention, polishing or cleaning refers to post-chemical mechanical planarization (post-CMP), and the alkaline compositions described herein can be used to remove debris and residues remaining on the semiconductor surface after a chemical mechanical planarization (CMP) process. CMP is well known as a technique aimed at removing specific layers on a semiconductor substrate by a combination of chemical and mechanical actions. The mechanical action is usually performed by a polishing pad. The polishing pad is generally pressed against the surface to be polished and mounted on a moving platen. In a typical CMP process, a rotating wafer holder brings the wafer to be polished into contact with the polishing pad. The CMP composition is usually pressed between the wafer to be polished and the polishing pad. On the other hand, polishing particles (e.g., silica particles) in the CMP composition are essential to achieve "chemical" polishing. Furthermore, the presence of certain chemicals (e.g., oxidizing agents such as peroxides) in the CMP composition is important to ensure a high removal rate for specific target layers / metals (e.g., copper and / or cobalt). However, the alkaline compositions described herein are essentially free of polishing particles (especially silica particles) or oxidizing agents (especially peroxides).

[0030] In the present invention, "essentially free" means that the composition does not contain the component in a concentration that would affect the cleaning function of the composition. The particle content is preferably less than 10 ppm, more preferably less than 1 ppm, and most preferably below the detection limit. In preferred embodiments, the composition is filtered before use to ensure that the particle concentration is below the required value. For example, preferably the composition is essentially free of abrasive particles and / or oxidizing agents, and preferably the concentration of abrasive particles and / or oxidizing agents in the composition is less than 10 ppm. However, trace amounts of particles / components that may remain on the semiconductor surface as part of the residue after the CMP process are not detrimental to cleaning applications using the alkaline compositions described herein.

[0031] For the purposes of this invention, a corrosion inhibitor refers to a chemical compound that forms a protective molecular layer on the surface of a metal.

[0032] In this specification, the term "aqueous" means that the compositions of the present invention contain water. The water content may vary considerably from composition to composition. The alkaline compositions described herein are aqueous compositions containing at least 50.0% by mass, preferably at least 60% by mass, more preferably at least 80% by mass, more preferably at least 90.0% by mass, and more preferably at least 90.0% by mass of water.

[0033] In this specification, the term "alkaline" means that the composition of the present invention has a pH in the range of 7.5 to 14.0, preferably 8.5 to 13.0, more preferably 8.5 to 12.5, more preferably 9.0 to 12.0, and most preferably 10.5 to 11.9.

[0034] In this specification, the term "copper inhibitor" means a compound that inhibits the static removal of copper from a substrate by etching. The term "cobalt inhibitor" means a compound that inhibits the static removal of cobalt from a substrate by etching.

[0035] All cited references are incorporated herein by reference.

[0036] The measurement techniques disclosed herein are well known to those skilled in the art.

[0037] In one embodiment of the present invention, an alkaline composition for cleaning a substrate comprising i) copper or a copper alloy, and ii) cobalt or a cobalt alloy, wherein the composition is: a) At least one pH adjuster selected from the compounds of formula I. [ka] (In the formula, Ra, Rb, Rd, and Rf are independent of each other, unsubstituted linear or branched C1-C 12 Selected from alkyl groups, Re is selected from unsubstituted linear or branched C4-C9 alkyl groups; however, the dashed bond between Re and N is either a single or double bond, and if the dashed bond is a double bond, Rd is absent. Ra, Rb, Re, and Rf are linked together to form one or more 6-membered or 7-membered rings. b) C2-C having at least two sulfonic acid groups or carboxylic acid groups 12 At least one complexing agent selected from hydrocarbons, c) At least one polymer dispersant having a mass-average molecular weight of 1000 g / mol or more; and d) Water-containing solvents Includes.

[0038] The alkaline composition of the present invention comprises components (a), (b), (c), (d), and optionally the following further components.

[0039] (a) pH adjuster According to the present invention, the composition comprises at least one pH adjusting agent selected from the compounds of formula I. [ka] (In the formula, Ra, Rb, Rd, and Rf are independent of each other, unsubstituted linear or branched C1-C 12 Selected from alkyl groups, Re is selected from unsubstituted linear or branched C4-C9 alkyl groups; however, the dashed bond between Re and N is either a single or double bond, and if the dashed bond is a double bond, Rd is absent. Ra, Rb, Re, and Rf are linked together to form one or more six-membered or seven-membered rings.

[0040] In this specification, a pH adjuster refers to a compound added to adjust the pH value of a composition to a predetermined value. As will become clear in the Examples section below, certain tertiary amine compounds of formula I or Ia ensure an alkaline pH while maintaining a low static etching rate (SER) for both copper and cobalt. In this specification, the pH adjuster is selected from tertiary amines and not from primary, secondary, or quaternary ammonium groups.

[0041] As used herein, the term "alkyl" refers to an unsubstituted saturated acyclic aliphatic group, including linear or branched alkyl saturated hydrocarbon radicals represented by the general formula CnH2n+1 (wherein n is the number of carbon atoms, e.g., 1, 2, 3, 4, etc.).

[0042] Unsubstituted linear C1-C 12 The alkyl group is preferably selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, or dodecyl, and more preferably selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, and nonyl.

[0043] Unsubstituted branched C1~C 12 The alkyl group is preferably selected from the group consisting of isopropyl, isobutyl, neopentyl, 2-ethylhexyl, 2-propylheptyl, 2-butyloctyl, 2-pentylnonyl, 2-hexyldecyl, isohexyl, isoheptyl, isooctyl, isononyl, isodecyl, and isododecyl, and more preferably selected from the group consisting of isopropyl, isobutyl, neopentyl, 2-ethylhexyl, 2-propylheptyl, 2-butyloctyl, 2-pentylnonyl, 2-hexyldecyl, isohexyl, isoheptyl, isooctyl, and isononyl.

[0044] Preferably, the composition comprises at least one pH adjuster selected from the compounds of formula I. [ka] (In the formula, Ra, Rb, Rd, and Rf are each independently selected from unsubstituted linear C1-C9 alkyl, Re is selected from unsubstituted linear or branched C4-C9 alkyl; provided that the dashed bond between Re and N is a single bond or a double bond, and when the dashed bond is a double bond, Rd does not exist, and Ra, Rb, Re, and Rf are bonded to form one or more 6-membered or 7-membered rings).

[0045] Preferably, Ra, Rb, Rd, and Rf are each independently selected from unsubstituted linear or branched C1-C 10 alkyl, more preferably from unsubstituted linear or branched C1-C9 alkyl, and even more preferably from unsubstituted linear or branched C1-C6 alkyl.

[0046] Even more preferably, Ra, Rb, Rd, and Rf are each independently selected from unsubstituted linear C1-C 12 alkyl, more preferably from unsubstituted linear C1-C9 alkyl, and most preferably from unsubstituted linear C1-C6 alkyl.

[0047] Preferably, Ra, Rb, Re, and Rf may be bonded to form one or two or three 6-membered or 7-membered rings. More preferably, they may be bonded to form one or two 6-membered or 7-membered rings.

[0048] Those skilled in the art will understand that when Ra, Rb, Re, and Rf are bonded to form a ring structure, one or more H from the alkyl group are replaced by C-C bonds to form a fused ring structure, and the carbon group bonded to the N atom becomes an alkylene group or a -C(H2)- group.

[0049] Preferably, the dashed bond between Re and N is a single bond.

[0050] Diamines are well known for their ability to chelate with metals (by forming a five- or six-membered ring with the metal ion forming the complex), but without being bound by theory, it has been noted that such ring-forming diamines result in undesirable high copper and / or cobalt etching rates (supported by the high SER values ​​in the Examples section below). For the purposes of the present invention, we believe that the carbon chain length of Re in the compound of formula I needs to be carefully adjusted to avoid ring formation or chelation. Preferably, Re is ≥ C4 alkyl. 、 More preferably, Re is ≥ C5 alkyl. On the other hand, especially when manufactured as a concentrated solution, the composition needs to have sufficiently high water solubility, and improving the solubility of the pH adjuster is important. In this regard, Re is ≥ C 10 Alkyl compounds of formula I have been shown to produce undesirable turbidity and are unsuitable for commercial use (see examples below). Preferably, Re is ≤C9 alkyl, and more preferably ≤C8 alkyl.

[0051] Preferably, Re is selected from unsubstituted linear or branched C4-C8 alkyl groups, and more preferably from unsubstituted linear or branched C5-C8 alkyl groups.

[0052] More preferably, Re is selected from unsubstituted linear C4-C9 alkyl groups, even more preferably from unsubstituted linear C4-C8 alkyl groups, and most preferably from unsubstituted linear C5-C8 alkyl groups.

[0053] Preferably, the pH adjusting agent is selected from the compounds of formula Ia. [ka] (In the formula, Ra and Rc are bonded to form a 6-membered ring or a 7-membered ring (A), more preferably a 7-membered ring (A), and Ra is unsubstituted linear or branched C1-C 12 (Selected from alkyl groups, where Rc is selected from unsubstituted linear C1-C9 alkyl groups).

[0054] More preferably, Rc is selected from unsubstituted linear C1-C6 alkyl groups, even more preferably from unsubstituted linear or branched C1-C6 alkyl groups, and more preferably from unsubstituted linear C1-C4 alkyl groups.

[0055] Preferably, the alkaline composition comprises at least one pH adjusting agent selected from compounds of formula I or formula Ia. [ka] (In the formula, Ra, Rb, Rd, and Rf are independent of each other, unsubstituted linear or branched C1-C 12 Selected from alkyl groups, more preferably at least one of Ra, Rb, Rd, and Rf in formula I is methyl, and even more preferably at least two of Ra, Rb, Rd, and Rf in formula I are methyl. Re is selected from unsubstituted linear or branched C4-C9 alkyl groups; the dashed bond between Re and N is a single bond. Rc is selected from unsubstituted linear C1-C9 alkyl groups. In formula Ia, Ra and Rc combine to form a 6-membered or 7-membered ring (A).

[0056] More preferably, Ra, Rb, Rd, and Rf in formula I or Ia are independently selected from unsubstituted linear or branched C1-C6 alkyl groups, and Rc is selected from unsubstituted linear C1-C4 alkyl groups.

[0057] Preferably, Ra, Rb, Rc, Re, and Rf do not contain further substituents, and in particular do not contain groups selected from -COOH and its derivatives, -SO3H and its derivatives, -OH, -OR, or halogens.

[0058] Preferably, the pH adjuster, i.e., the compound of formula I or Ia, has a solubility in water (at 25°C) of at least 70 g / L, more preferably at least 150 g / L, even more preferably at least 200 g / L, and even more preferably at least 400 g / L, and more preferably the pH adjuster is completely miscible with water at 25°C (soluble at all concentrations).

[0059] The pH adjuster may be a gas, liquid, or solid, but is preferably solid or liquid, most preferably liquid (at 20°C). Liquid amines are easier to handle than gaseous amines and are not bound by theory, however gaseous amines (e.g., N,N,N-trimethylamine) can cause an undesirable increase in etching rate, particularly when the substrate is exposed to the vapor of the composition and the pH adjuster exhibits a high vapor pressure. Preferably, the pH adjuster has a boiling point (1 atm or 10¹³ millibar) of at least 5°C, more preferably at least 20°C, and even more preferably at least 35°C.

[0060] In this invention, pKa refers to the most acidic proton associated with the N atom on the pH adjusting agent, i.e., the compound of formula I or Ia. As mentioned above, pH adjusting agents play an important role in ensuring an alkaline pH, but at the same time, it is desirable that the pKa of the pH adjusting agent be within a range that can overcome environmental regulations and processing challenges. For example, substances classified as highly corrosive add processing and transportation challenges during manufacturing.

[0061] Preferably, the pH adjusting agent has a pKa of 13.5, more preferably 13.0 or less, and even more preferably 12.5 or less. Preferably, the pH adjusting agent has a pKa of 9.0 or more, more preferably 9.2 or more, even more preferably 9.5 to 13.5, and even more preferably 9.9 to 12.1.

[0062] More preferably, the pH adjuster is selected from N,N,N,N-tetramethyl-1,6-hexanediamine, N,N,N,N-tetramethyl-1,5-pentanediamine, N,N,N,N-tetramethyl-1,4-butanediamine, N,N,N,N-tetramethyl-1,7-heptanediamine, N,N,N,N-tetramethyl-1,8-octanediamine, 1,5-diazabicyclo[4.4.0]decane-5-ene, 1,8-diazabicyclo[5.4.0]undecane-7-ene, and 1,9-diazabicyclo[6.4.0]dodecane-8-ene.

[0063] Preferably, the concentration of the pH adjusting agent (a) is in the range of 0.02% by mass or more and 40.0% by mass or less, based on the total mass of the composition.

[0064] The concentration of pH adjuster (a) is preferably 40.0% by mass or less, more preferably 39.0% by mass or less, even more preferably 38.0% by mass or less, particularly 36.5% by mass or less, even more preferably 35.0% by mass or less, and most preferably 32.0% by mass or less, based on the total mass of the composition. At concentrations exceeding 40.0% by mass, colloidal instability and / or phase separation of the composition is observed, particularly in the presence of one or more water-miscible organic solvents. The concentration of pH adjuster (a) is preferably at least 0.02% by mass, more preferably at least 0.05% by mass, even more preferably at least 0.06% by mass, particularly at least 0.07% by mass, even more preferably at least 0.08% by mass, even more preferably at least 0.085% by mass, more preferably at least 0.09% by mass, and most preferably at least 0.1% by mass, based on the total mass of the composition. The concentration of the pH adjuster (a) is more preferably in the range of 0.05% by mass or more and 38.0% by mass or less, and most preferably in the range of 0.1% by mass or more and 32.0% by mass or less, based on the total mass of the composition.

[0065] (b) Complexing agent According to the present invention, the alkaline composition for cleaning the substrate is a C2-C2 compound having at least two sulfonic acid groups or carboxylic acid groups. 12It comprises at least one complexing agent selected from hydrocarbons.

[0066] Generally, complexing agents in liquid media can dissolve metal salts by forming complexes that dissolve well with metal ions, preventing the dissolved metal ions from forming insoluble precipitates, and thus facilitating the removal of residues.

[0067] Preferably, the complexing agent is a C2-C complexing agent having at least two sulfonic acid groups or carboxylic acid groups. 10 hydrocarbons, more preferably C3-C 10 The complexing agent is selected from hydrocarbons. The complexing agent may further contain one or more N donors, such as amine or pyridine type N, or phenol type OH groups, in order to form a complex with the metal ion. The complexing agent may also contain further functional groups such as hydroxyl or chloro groups.

[0068] More preferably, the complexing agent is a C2-C compound having at least two carboxylic acid groups and optionally one or more chloro and / or hydroxyl functional groups. 12 Selected from hydrocarbons.

[0069] More preferably, the complexing agent is selected from alendronic acid, phthalic acid, citric acid, tartaric acid, tartonic acid, adipic acid, oxalic acid, malonic acid, aspartic acid, succinic acid, glutaric acid, glutamic acid, pimelic acid, sebacic acid, suberic acid, azelaic acid, sebacic acid, oxalic acid, malic acid, maleic acid, gluconic acid, pimelic acid, muconic acid, ethylenediaminetetraacetic acid, propylenediaminetetraacetic acid, N,N-bis(carboxymethyl)alanine, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, bis(salicylidene)ethylenediamine, aminotris(methylenephosphonic acid), diethylenetriaminepentakis(methylphosphonic acid), ethylenediaminetetra(methylenephosphonic acid), or mixtures thereof.

[0070] More preferably, the complexing agent is selected from phthalic acid, citric acid, tartaric acid, tartonic acid, adipic acid, oxalic acid, malonic acid, aspartic acid, succinic acid, glutaric acid, glutamic acid, oxalic acid, malic acid, maleic acid, gluconic acid, ethylenediaminetetraacetic acid, propylenediaminetetraacetic acid, N,N-bis(carboxymethyl)alanine, nitrilotriacetic acid, diethylenetriaminepentaacetic acid, bis(salicylidene)ethylenediamine, aminotris(methylenephosphonic acid), diethylenetriaminepentakis(methylphosphonic acid), ethylenediaminetetra(methylenephosphonic acid), or mixtures thereof.

[0071] More preferably, the complexing agent is selected from citric acid, tartaric acid, tartonic acid, malonic acid, succinic acid, glutaric acid, malic acid, or a mixture thereof.

[0072] Most preferably, the complexing agent is citric acid.

[0073] Preferably, the complexing agent (b) is present in an amount ranging from 0.005% by mass to 3.0% by mass, based on the total mass of the composition.

[0074] More preferably, the complexing agent (b) is present in an amount of 3.0% by mass or less, more preferably 2.0% by mass or less, and most preferably 1.0% by mass or less, based on the total mass of the composition. The amount of (b) is preferably at least 0.005% by mass, more preferably at least 0.008% by mass, and most preferably at least 0.01% by mass, based on the total mass of the composition. The concentration of the complexing agent (b) is more preferably in the range of 0.05% by mass to 4.0% by mass, and most preferably in the range of 0.008% by mass to 1.0% by mass, based on the total mass of the composition.

[0075] (c) Polymer dispersant According to the invention described herein, the composition comprises at least one polymer dispersant (c) having a mass-average molecular weight of ≥1000 g / mol.

[0076] While not bound by theory, this polymer dispersant contributes to dispersing silica particles remaining after CMP cleaning. Part of the dispersant adsorbs onto the surface of the particles to be dispersed, for example. Another part of the dispersant extends from the particles into the solution, for example. Literature on the structure of adsorbent polymers is well-known in the art, and can be found, for example, in Lipatov and Sergeeva, Adsorption of Polymers, 1974. The dispersant portion in the solvent can rinse particles from the surface of the substrate being cleaned. Improved interaction with the solvent strengthens the barriers between particles or between particles and the substrate surface, ensuring that aggregation or re-adhesion does not occur.

[0077] The chemical properties of the solvated portion and the portion adsorbed on the particle surface may be identical or different. Similar dispersion mechanisms and dispersants are well known in the art and are described, for example, in Chapter 7 of TFTadros, Applied Surfactants - Principles and Application (first edition 2005).

[0078] As observed in Table 1 below, polymer dispersant (C), which includes at least one polymer dispersant (c) having a mass-average molecular weight of ≥1000 g / mol, ensures low cobalt and copper SER while preventing undesirable precipitation or aggregation.

[0079] Preferably, the polymer dispersant (c) having a mass-average molecular weight of ≥1000 g / mol is selected from anionic, zwitterionic, nonionic, or cationic polymers. Among these, anionic and nonionic polymers are preferred. These polymers may be homopolymers or copolymers from anionic or nonionic monomers.

[0080] Examples of monomers include ethylene oxide, propylene oxide, styrene, vinylpyrrolidone, acrylamide, amino acids, carbohydrates, vinyl alcohol, maleic acid, vinyl sulfonic acid, vinylphosphonic acid, formaldehyde, phenolsulfonic acid, naphthalenesulfonic acid, phenol, or mixtures thereof.

[0081] More preferably, the dispersant is an anionic homopolymer or copolymer containing monomer units selected from sulfate groups or phosphonic acid groups, or a nonionic polymer containing monomer units selected from ethylene oxide or vinylpyrrolidone.

[0082] Preferably, the polymer dispersant (c) having a mass-average molecular weight of ≥1000 g / mol is not selected from polymers or copolymers of acrylic acid. Although not bound by theory, the presence of polymers or copolymers of acrylic acid results in an undesirable increase in the cobalt etching rate (SER).

[0083] Preferred polymers are polyvinylpyrrolidone, polyethylene oxide, ethylene oxide propylene oxide copolymer, naphthalene sulfonic acid formaldehyde condensate, phenol sulfonic acid formaldehyde condensate, or naphthalene sulfonic acid phenol sulfonic acid formaldehyde mixed condensate. Polymers obtained by condensation of aromatic compounds and aldehyde compounds may also contain phenol, cresol, or xylenol units.

[0084] According to the present invention, the mass-average molecular weight (M) of the polymer dispersant is w The mass-average molecular weight (M) of the polymer dispersant is 1000 g / mol or more. Preferably, the mass-average molecular weight (M) of the polymer dispersant is 1000 g / mol or more. w The concentration is 1100 g / mol or more, more preferably 1500 g / mol or more, and most preferably 1800 g / mol or more. <1000 g / mol w Polymers having are known to be inert in terms of dispersibility or have low surface activity. Preferably, the mass average molecular weight M of the polymer dispersant.w The concentration is 100,000 g / mol or less, more preferably 80,000 g / mol or less, even more preferably 50,000 g / mol or less, and most preferably 20,000 g / mol or less. >1000 g / mol M w Polymers possessing this characteristic have undesirable high viscosity and low water solubility, making processing difficult. The mass-average molecular weight is determined by gel permeation chromatography.

[0085] Preferably, the polymer dispersant (c) is not selected from cationic polymers or copolymers. Although not bound by theory, the use of cationic copolymers in the composition may result in insufficient cleaning, particularly with respect to silica removal. Furthermore, cationic polymers (if present in the composition) negatively interact with carboxylic acid hydrocarbons and may form undesirable emulsions. Preferably, the content of cationic polymers or copolymers, such as polyethyleneimine (PEI) or cationic polyacrylamide, in the composition is <0.01% by mass relative to the total mass of the composition.

[0086] Preferably, the polymer dispersant (c) is present in an amount ranging from 0.001% by mass to 3.0% by mass, based on the total mass of the composition.

[0087] More preferably, the polymer dispersant (c) is 2.5% by mass or less, more preferably 2.0% by mass or less, most preferably 1.5% by mass or less, and most preferably 1.0% by mass or less, based on the total mass of the composition. The amount of (c) is preferably at least 0.005% by mass, more preferably at least 0.008% by mass, and most preferably at least 0.01% by mass, based on the total mass of the composition. The concentration of the polymer dispersant (c) is more preferably in the range of 0.005% by mass to 2.5% by mass, more preferably in the range of 0.008% by mass to 1.5% by mass, and most preferably in the range of 0.01% by mass to 1.0% by mass, based on the total mass of the composition.

[0088] (d) solvents containing water According to the present invention, the composition comprises a solvent (d) containing water.

[0089] Water is a particularly preferred medium for the compositions of the present invention. Preferably, solvent (d) consists essentially of water.

[0090] The presence of a water-miscible organic solvent in combination with water does not adversely affect performance. Preferably, solvent (d) can be a combination of water and one or more water-miscible organic solvents. In the context of the present invention, the term "water-miscible organic solvent" preferably means that an organic solvent satisfying this requirement is miscible with water in a ratio of at least 1:1 (by mass) at 20°C and atmospheric pressure. Preferably, the water-miscible organic solvent is selected from C1-C4 alcohols such as isopropyl alcohol, dimethyl sulfoxide (DMSO), γ-butyrolactone, sulforane, alkylene glycols and alkylene glycol derivatives, such as ethylene glycol and propylene glycol. In particular, preferred compositions of the present invention do not contain one or more water-miscible organic solvents.

[0091] In this specification, if the total amount of components other than component (d) is y mass% based on the total mass of the composition, then the amount of component (d) is (100-y) mass% of the composition.

[0092] The amount of solvent (d) in the composition is preferably 99.99% by mass or less, more preferably 99.9% by mass or less, most preferably 99.8% by mass or less, particularly preferably 99.5% by mass or less, particularly 97.0% by mass or less, for example 95.0% by mass or less, based on the total mass of the composition. The amount of solvent (d) in the composition is preferably at least 30.0% by mass, more preferably at least 50.0% by mass, most preferably at least 55.5% by mass, particularly preferably at least 62.5% by mass, particularly preferably at least 75.0% by mass, for example at least 80.0% by mass, based on the total mass of the composition.

[0093] The composition further comprises any additive selected from reducing agents, oxygen scavengers, wetting agents, bactericides, or mixtures thereof. Preferably, the composition is essentially free of one or more of these additives. More preferably, the composition is essentially free of wetting agents and / or reducing agents.

[0094] Reducing agent Residues of oxidizing agents such as peroxides, persulfates, and periodates may be present from previous process steps, such as CMP or etching, potentially causing corrosion of the fine metal structure on the wafer during subsequent cleaning steps. To prevent this, a reducing agent may be optionally added to the composition to neutralize the residual oxidizing agent. Preferably, the reducing agent is selected from organic compounds containing at least one primary or secondary hydroxyl group. A preferred type of reducing agent is a saturated organic compound containing at least four hydroxyl groups.

[0095] A more preferred type of reducing agent is a saturated organic compound containing at least four alcoholic hydroxyl groups, where one of these hydroxyl groups is a primary hydroxyl group. Preferred reducing agents include pentaerythritol, tetrahydroxybutane, pentahydroxypentane, hexahydroxyhexane, and 1,4-sorbitan. This compound may form an acetal compound with a carbohydrate such as isomalt, or it may be a free molecule such as mannitol. A more preferred type of reducing agent is a sugar alcohol containing at least four hydroxyl groups. Examples of such sugar alcohols include sorbitol, arabitol, arabinitol, isomalt, mannitol, threotol, erythritol, xylitol, or lactitol. This compound may form an acetal compound with a carbohydrate such as isomalt, or it may be a free molecule such as mannitol. Particularly preferred reducing agents are sorbitol or xylitol.

[0096] Preferably, the reducing agent is present in an amount ranging from 0.01% by mass to 7.0% by mass, based on the total mass of the composition.

[0097] More preferably, the reducing agent is present in an amount of 7.0% by mass or less, more preferably 5.0% by mass or less, and most preferably 3.0% by mass or less, based on the total mass of the composition. The amount of the reducing agent is preferably at least 0.01% by mass, more preferably at least 0.03% by mass, and most preferably at least 0.05% by mass, based on the total mass of the composition. The concentration of the reducing agent is more preferably in the range of 0.05% by mass to 5.0% by mass, and most preferably in the range of 0.06% by mass to 3.0% by mass, based on the total mass of the composition.

[0098] Oxygen scavenger Oxygen dissolved in the solvent can damage the fine metal patterns on the substrate. To prevent this, an oxygen scavenger can be added.

[0099] Oxygen scavengers are typically unsaturated organic compounds containing at least one CC double bond. This double bond is either isolated or part of a conjugated or aromatic system. Preferred types of oxygen scavengers are furanones and their derivatives, e.g., 2-furanone, 3-methyl-2-furanone, 4-hydroxy-2,5-dimethyl-3-furanone, 5-hydroxymethyl-2-furanone, 5-ethyl-3-hydroxy-4-methyl-2-furanone, ascorbic acid, or erythrobic acid. More preferred are furanone derivatives having at least two OH groups in the furanone ring, e.g., ascorbic acid or erythrobic acid. Ascorbic acid is particularly preferred.

[0100] Another type of preferred oxygen scavenger is phenol derivatives. Examples include tyrosine, dihydroxybenzene, its isomers such as hydroquinone, catechol, resorcinol, and derivatives such as 4-methoxyphenol (MeHQ), trihydroxybenzene, its isomers such as pyrogallol and phloroglucin, and derivatives such as gallic acid and tannin compounds, tetrahydroxybenzene, its isomers and derivatives.

[0101] Most preferably, the oxygen scavenger is selected from ascorbic acid, 4-methoxyphenol, or gallic acid.

[0102] Preferably, the composition does not contain an oxygen scavenger in any way. If an oxygen scavenger is present in the composition, the amount of the oxygen scavenger in the composition is preferably 10.0% by mass or less, more preferably 8.0% by mass or less, and most preferably 5.0% by mass or less, based on the total mass of the composition. The amount of the oxygen scavenger in the composition is preferably at least 0.01% by mass, more preferably at least 0.03% by mass, most preferably at least 0.05% by mass, particularly preferably at least 0.08% by mass, and particularly at least 0.1% by mass, based on the total mass of the composition.

[0103] Humectant The compositions of the present invention may optionally contain a wetting agent. Suitable wetting agents are well known to those skilled in the art and are typically molecules consisting of at least one hydrophobic moiety and at least one hydrophilic moiety, such as surfactants.

[0104] Preferably, the wetting agent is selected from anionic, nonionic, or cationic surfactants, and more preferably from nonionic surfactants. Even more preferably, the wetting agent is selected from the following: - Preferably, ethylene oxide, propylene oxide or higher alkylene oxide, and C8-C 10 Alkoxylated fatty alcohols, which are adducts with fatty alcohols, are particularly preferred as wetting agents in BASF's Plurafac LF series. - Preferably C8~C 20 Alkyl polyglucosides from alkyl polyglucosides, particularly preferably BASF's Glucopon series of wetting agents, - C 12 ~C 24 Alkylcarboxylic acid or sarcosine, preferably C 12 ~C 24Alkyl sarcosines, particularly preferred are N-oleyl sarcosine, N-cocoyl sarcosine, N-lauroyl sarcosine, or 4-butylbenzoyl sarcosine.

[0105] Preferably, the wetting agent has a cloud point measured in water according to DIN 53917 at ≥30°C, more preferably ≥35°C. Even more preferably, the cloud point is measured in water according to DIN 53917 and is 30°C to 50°C, most preferably 35°C to 45°C.

[0106] Preferably, the composition is essentially free of wetting agents. If a wetting agent is present in the composition, the amount of wetting agent in the composition is preferably 10.0% by mass or less, more preferably 8.0% by mass or less, and most preferably 5.0% by mass or less, based on the total mass of the composition. The amount of wetting agent in the composition is preferably at least 0.005% by mass, more preferably at least 0.008% by mass, most preferably at least 0.01% by mass, particularly preferably at least 0.015% by mass, and particularly preferably at least 0.018% by mass, based on the total mass of the composition.

[0107] composition The properties of a composition may depend on the pH of the corresponding composition. According to the present invention, an alkaline composition has a pH in the range of 7.5 to 14.0. Preferably, the pH value of the composition is 8.5 or higher, more preferably 9.0 or higher, most preferably 9.5 or higher, particularly preferably 10.0 or higher, and most preferably 10.5 or higher. Preferably, the pH value of the composition is 14.0 or lower, more preferably 13.5 or lower, most preferably 13.0 or lower, particularly preferably 12.5 or lower, and most preferably 11.5 or lower. Preferably, the pH of the composition is in the range of 8.5 to 13.0, more preferably 8.7 to 12.5, and even more preferably 9.0 to 11.5. For comparison, the pH values ​​described herein and in the Examples section relate to diluted compositions. When comparing the pH of concentrated forms, those skilled in the art will expect slight variations in the values ​​described herein. In this regard, pH variations are expected to be in the range of ±1.5, more preferably ±1.3.

[0108] Preferably, the composition is essentially free of particles, particularly silica particles. "Simply free" means that it does not contain particles in an amount that would affect the cleaning function of the composition. The particle content is preferably less than 10 ppm, more preferably less than 1 ppm, and most preferably below the detection limit. In a preferred embodiment, the composition is filtered before use.

[0109] Preferably, the composition is essentially free of oxidizing agents, particularly peroxides. Essentially free means that the composition does not contain activated oxidizing agents that increase the corrosion of copper or cobalt, but ambient oxygen (O2) dissolved in the composition is specifically excluded. Preferably, the oxidizing agent content (excluding O2) in the cleaning composition is less than 10 ppm, more preferably less than 1 ppm. Most preferably 、 The content of oxidizing agents (excluding O2) is also below the detection limit.

[0110] Preferably, the composition is essentially free of metal ions such as sodium or calcium. These metal ions are not actively added to the composition, but their presence in trace amounts (preferably less than 10 ppm, more preferably less than 1 ppm) does not adversely affect the performance or cleaning function of the composition. While the absence of sodium or similar metal ions is preferable, their presence, for example, as part of a salt in one or more components, does not adversely affect the performance of the composition.

[0111] Preferably, the composition does not contain film-forming agents in any way, and in particular does not contain triazoles, benzotriazoles, substituted triazoles, or their derivatives. Even if these agents are not actively added to the composition, their presence in trace amounts (preferably less than 10 ppm, more preferably less than 1 ppm) does not adversely affect the performance or cleaning functionality of the composition.

[0112] A preferred embodiment of the present invention is the following components, as defined herein and based on the examples, all based on the total mass of the composition: a) pH adjuster in an amount of 0.02 to 40.0% by mass; b) 0.005 to 3.0% by mass of C2-C2 compounds having at least two sulfonic acid groups or carboxylic acid groups. 12 Complexing agents selected from hydrocarbons; c) A polymer dispersant having a mass-average molecular weight of ≥1000 g / mol, in an amount of 0.001% to 3.0% by mass; and The remaining water-containing solvent The present invention relates to an alkaline composition containing the following, wherein the pH of the composition is about 7.5 to about 13.0, preferably about 9 to about 11.0, and the total mass percentage of each component is 100%. The concentrations of components (a) to (d) can be varied within the preferred range described above.

[0113] Another preferred embodiment of the present invention relates to an alkaline composition for cleaning substrates comprising i) copper or a copper alloy, and ii) cobalt or a cobalt alloy, wherein the composition comprises the following components as defined herein and based on the examples, all based on the total mass of the composition: a) pH adjuster in an amount of 0.02 to 40.0% by mass; b) 0.005 to 3.0% by mass of C2-C2 compounds having at least two sulfonic acid groups or carboxylic acid groups. 12 Complexing agents selected from hydrocarbons; c) A polymer dispersant having a mass-average molecular weight of ≥1000 g / mol, in an amount of 0.001% to 3.0% by mass; and The remaining water-containing solvent The composition contains the following components, where the pH of the composition is about 7.5 to about 13.0, preferably about 9 to about 11.0, and the mass percentage of each component totals 100%. The concentrations of components (a) to (d) can be varied within the preferred range described above.

[0114] Another preferred embodiment of the present invention relates to an alkaline composition for cleaning substrates comprising i) copper or a copper alloy, and ii) cobalt or a cobalt alloy, wherein the composition comprises the following components as defined herein and based on the examples, all based on the total mass of the composition: a) pH adjuster in an amount of 0.02 to 40.0% by mass; b) 0.005 to 3.0% by mass of at least one complexing agent selected from citric acid, tartaric acid, tartonic acid, malonic acid, succinic acid, glutaric acid, malic acid, or a mixture thereof; c) At least one polymer dispersant having a mass-average molecular weight of ≥1000 g / mol, selected from polyvinylpyrrolidone, polyethylene oxide, ethylene oxide propylene oxide copolymer, naphthalene sulfonic acid formaldehyde condensate, phenol sulfonic acid formaldehyde condensate, or naphthalene sulfonic acid phenol sulfonic acid formaldehyde mixed condensate, in an amount of 0.001% to 3.0% by mass; and The remaining water-containing solvent The composition contains the following components, where the pH of the composition is about 7.5 to about 13.0, preferably about 9 to about 11.0, and the mass percentage of each component totals 100%. The concentrations of components (a) to (d) can be varied within the preferred range described above.

[0115] The compositions of the present invention can be prepared by a normal, standard mixing process, and the components of the composition can be mixed in desired amounts using mixing equipment such as a stirring tank, an in-line dissolver, a high-shear impeller, an ultrasonic mixer, a homogenizer nozzle, or a countercurrent mixer.

[0116] It will be understood that it is a common practice to prepare a concentrated form of the composition to be diluted before use. For example, a composition may be prepared in a more concentrated form and then diluted with water and any water-miscible solvent (collectively referred to as diluents) or other components before and / or during use. The dilution ratio may range from 0.01 parts of the composition concentrate to about 1.0 part of the diluent to 1 part of the composition concentrate to about 200 parts of the diluent. Preferably, the ratio of diluent to concentrate is in the range of 150:1 to 10:1, more preferably in the range of 120:1 to 20:1.

[0117] In particular, using water, water-miscible organic solvents, or a combination thereof, the following components: a) At least one pH adjusting agent in an amount of 4.0 to 40.0% by mass, preferably 5.0 to 38.0% by mass, and more preferably 7.0 to 32.0% by mass; b) At least one complexing agent in an amount of 0.1 to 3.0% by mass, preferably 0.8 to 3.0% by mass, and more preferably 0.85 to 2.0% by mass; c) at least one polymer dispersant in an amount of 0.005% to 3.0% by mass, preferably 0.008% to 3.0% by mass, more preferably 0.01% to 2.5% by mass; and d) The remaining water-containing solvent It can be prepared by diluting a concentrated solution containing [the specified substance]. A preferred dilution ratio (by mass) is approximately 30 times or more. More preferably 50 times or more. Even more preferably 75 times or more. Even more preferably 100 times or more.

[0118] Purpose The composition of the present invention is suitable for the method of the present invention.

[0119] However, the main objective of the method of the present invention is to process substrates useful for the manufacture of electrical devices, particularly semiconductor integrated circuits (ICs), liquid crystal panels; organic electroluminescent panels; printed circuit boards; micromachines; DNA chips; microplants and magnetic heads; ICs preferably equipped with LSIs (large-scale integrated circuits) or VLSIs (very large-scale integrated circuits); and optical devices, particularly optical glass, e.g., photomasks, lenses and prisms; inorganic conductive films, e.g., indium tin oxide (ITO); optical integrated circuits; optical switching elements; optical waveguides; optical single crystals, e.g., optical fiber end faces and scintillators; solid-state laser single crystals; sapphire substrates for blue laser LEDs; semiconductor single crystals; and glass substrates for magnetic disks.

[0120] Preferably, the method of the present invention includes a surface treatment, pre-plating cleaning, post-etching cleaning, or post-CMP cleaning step, particularly a post-etching or post-CMP cleaning step.

[0121] The cleaning composition is particularly effective for removing from substrates including (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface. (a) Post-etching residue (PERR) or post-ashing residue (PARR), (b) chemical mechanical planarization (CMP) residue; This is useful for removing it.

[0122] The method of the present invention is particularly suitable for processing substrates that are useful for manufacturing ICs equipped with LSIs or VLSIs, especially in back-end-of-line (BEOL) processing.

[0123] The method of the present invention is most particularly suitable for post-CMP cleaning of semiconductor wafers in the manufacture of ICs with LSIs or VLSIs, especially by copper damascene or dual damascene processes.

[0124] Accordingly, one embodiment relates to a kit for assembly at a manufacturing facility or site of use, comprising one or more containers containing one or more components suitable for forming the compositions described herein. For assembly at a manufacturing facility or site of use, preferably, one container contains at least one pH adjuster and at least one complexing agent, and a second container contains the remaining components, e.g., at least one complexing agent, at least one polymer dispersant, a solvent including water, and optionally other components described herein.

[0125] In using the compositions described herein, the compositions are typically brought into contact with the device structure for a sufficient time, from about 25 seconds to about 200 minutes, preferably from about 5 minutes to about 60 minutes, at a temperature in the range of about 10°C to about 80°C, preferably from about 20°C to about 60°C. Such contact times and temperatures are exemplary, and other suitable time and temperature conditions effective in achieving the required removal selectivity may also be used.

[0126] After achieving the desired cleaning action, the composition can be easily removed from the pre-applied microelectronic device by, for example, rinsing, washing, or other removal steps. This may be desirable and effective in certain end uses of the composition of the present invention. For example, the device may be rinsed with a rinsing solution containing deionized water, an organic solvent, and / or dried (e.g., spin-drying, N2 drying). 、 It can be dried using methods such as steam drying.

[0127] The cleaning compositions described herein are particularly advantageous for removing residues after etching or ashing (PERR, PARR), post-CMP cleaning, surface treatment, and pre-metall plating cleaning of substrates containing both cobalt or cobalt alloy surfaces and copper or copper alloy surfaces.

[0128] The cleaning compositions described herein are advantageously used in a method for manufacturing semiconductor devices, the method comprising the following steps: (a) A step of providing a microelectronic substrate comprising (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface, having etching residue, ashing residue, or chemical mechanical planarization (CMP) residue; (b) A step of providing the composition described herein; (c) A step of bringing the composition into contact with (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface for a time and temperature effective in removing at least partially the etching residue, ashing residue, or chemical mechanical planarization (CMP) residue from the substrate. Includes.

[0129] Preferably, post-etching residue, post-ashing residue, or chemical mechanical planarization (CMP) residue is completely removed from the substrate.

[0130] The static etching rate (SER) of copper is preferably less than 4.0 Å / min, more preferably less than 3.5 Å / min, even more preferably less than 3.3 Å / min, and most preferably less than 3.0 Å / min.

[0131] The static etching rate (SER) of cobalt is preferably less than 5.0 Å / min, more preferably less than 4.0 Å / min, even more preferably less than 3.0 Å / min, and most preferably less than 2.5 Å / min.

[0132] The static etching rate was measured by the standard method described in the Examples section of this specification.

[0133] The composition according to the present invention has at least one of the following advantages: (1) The etching suppression performance has been adequately improved for both copper and cobalt (demonstrated by a low SER value); (2) The composition of the present invention provides a stable formulation or dispersion that does not undergo phase separation, aggregation, or precipitation, particularly in alkaline regions; (3) The composition of the present invention enables easy processing, such as compatibility with industrially important processes such as microfiltration; (4) The method of the present invention is easy to apply and can be carried out in as few steps as possible; (5) The compositions and methods of the present invention are prepared with moderately or less corrosive components, thus improving economic feasibility, processability, packageability, transportability, etc. (6) The composition of the present invention aims to provide a sufficiently low etching rate while preventing undesirable surface defects and ensuring high surface quality.

[0134] Embodiment A list of embodiments is provided below to further illustrate this disclosure, but this disclosure is not intended to limit itself to the specific embodiments described below.

[0135] 1. An alkaline composition for cleaning substrates containing i) copper or copper alloys, and ii) cobalt or cobalt alloys: a) At least one pH adjuster selected from the compounds of formula I. [ka] (In the formula, Ra, Rb, Rd, and Rf are independent of each other, unsubstituted linear or branched C1-C 12 Selected from alkyl groups, Re is selected from unsubstituted linear or branched C4-C9 alkyl groups; however, the dashed bond between Re and N is either a single or double bond, and if the dashed bond is a double bond, Rd is absent. Ra, Rb, Re, and Rf combine to form one or more 6-membered or 7-membered rings. b) C2-C having at least two sulfonic acid groups or carboxylic acid groups 12 At least one complexing agent selected from hydrocarbons, c) At least one polymer dispersant having a mass-average molecular weight of 1000 g / mol or more; and d) Water-containing solvents A composition containing the following:

[0136] 2. Ra, Rb, Re, and Rf combine to form the compound of formula Ia. [ka] The composition according to Embodiment 1 (wherein Ra and Rc are bonded to form a 6-membered ring or a 7-membered ring (A), more preferably a 7-membered ring (A) of formula Ia).

[0137] 3. The composition according to Embodiment 1 or 2, wherein Ra, Rb, Rd, and Rf are independently selected from unsubstituted linear or branched C1-C6 alkyl groups, and Rc is selected from unsubstituted linear C1-C4 alkyl groups.

[0138] 4. The composition according to any one of Embodiments 1 to 3, wherein the pH adjusting agent has a pKa of 9.0 or higher, preferably 9.0 to 12.0.

[0139] 5. The composition according to any one of Embodiments 1 to 4, wherein the dispersant is selected from polyvinylpyrrolidone, polyethylene oxide, ethylene oxide propylene oxide copolymer, naphthalene sulfonic acid formaldehyde condensate, phenol sulfonic acid formaldehyde condensate, or naphthalene sulfonic acid phenol sulfonic acid formaldehyde mixed condensate.

[0140] 6. The composition according to any one of Embodiments 1 to 5, wherein the complexing agent is selected from citric acid, tartaric acid, tartonic acid, malonic acid, succinic acid, glutaric acid, malic acid, or a mixture thereof.

[0141] 7. The composition according to any one of Embodiments 1 to 6, further comprising a reducing agent selected from sugar alcohols, particularly sorbitol, in an amount preferably 0.01 to 7.0% by mass, more preferably 0.07 to 5.0% by mass.

[0142] 8. A composition according to any one of Embodiments 1 to 7, which is essentially free from triazoles, quaternary ammonium salts, alkanolamines, or derivatives thereof.

[0143] 9. The composition according to any one of Embodiments 1 to 8, further comprising an oxygen scavenger selected from ascorbic acid, 4-methoxyphenol, or gallic acid.

[0144] 10. The composition according to any one of Embodiments 1 to 9, wherein the solvent is essentially water.

[0145] 11. The composition according to any one of Embodiments 1 to 10, further comprising a water-miscible organic solvent, preferably in an amount of 0.1 to 20% by mass.

[0146] 12. The composition according to any one of Embodiments 1 to 11, wherein the pH is 7.5 to 14.0, preferably 9.0 to 12.5.

[0147] 13. a) pH adjusting agent in an amount of 0.02 to 40.0% by mass; b) 0.005 to 3.0% by mass of a complexing agent; c) 0.001% to 3.0% by mass of a polymer dispersant; and The remaining water-containing solvent A composition according to any one of embodiments 1 to 12, comprising:

[0148] 14. A concentrate for preparing the composition according to any one of Embodiments 1 to 13, a) 0.02 to 40.0% by mass, preferably 7.0 to 38.0% by mass, of a pH adjusting agent; b) 0.005 to 3.0% by mass, preferably 0.3 to 3.0% by mass, of a complexing agent; c) 0.001% to 3.0% by mass, preferably 0.1% to 3.0% by mass, of a polymer dispersant; and The remaining water-containing solvent A concentrated liquid containing [the specified ingredient].

[0149] 15. A composition according to any one of Embodiments 1 to 13 is used on a substrate including (i) a surface of cobalt or a cobalt alloy and (ii) a surface of copper or a copper alloy. (a) Post-etching residue (PERR) or post-ashing residue (PARR), (b) chemical mechanical planarization (CMP) residue; A method used to remove it.

[0150] 16. A process for processing microelectronic devices, comprising the following steps: (a) a step of providing a microelectronic substrate having etching residue, ashing residue, or chemical mechanical planarization (CMP) residue, including (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface; (b) A step of providing the composition according to any one of Embodiments 1 to 13; (c) A step of bringing the composition into contact with (i) the surface of cobalt or a cobalt alloy and (ii) the surface of copper or a copper alloy for a time and temperature effective in removing at least partially, preferably completely, the post-etching residue, post-ash residue, or chemomechanical planarization (CMP) residue from the substrate. A process that includes this.

[0151] 17. A method for manufacturing a semiconductor device, comprising the process described in Embodiment 16.

[0152] Although the present invention has been described in relation to its particular embodiments, certain modifications and equivalents will be obvious to those skilled in the art, and these are intended to be within the scope of the present invention. [Examples]

[0153] The following materials of electronic grade purity were used. All amounts of compounds in the composition are absolute amounts, i.e., amounts excluding water, in the entire mixture.

[0154] pH adjuster: A-1: N,N,N',N'-Tetramethyl-1,6-Hexanediamine A-2:1,8-diazabicyclo[5.4.0]undeca-7-en A-3: Tri-N-ethylamine (for comparison) A-4: Tri-N-propylamine (for comparison) A-5: N,N,N',N'-tetramethyl-1,10-decanediamine (for comparison) A-6: N-methylethanolamine (for comparison) A-7: N,N,N',N'-tetramethyl-1,3-propanediamine (for comparison) A-8: 2-(dimethylamino)-2-methylpropan-1-ol (for comparison) A-9: 2-amino-2-methylpropan-1-ol (for comparison) A-10: Choline hydroxide (for comparison) A-11: 1,4-Diazabicyclo[2.2.2]octane (for comparison) A-12: 1,3,5-triazine (for comparison) A-13: N-ethylpyrrolidine (for comparison) A-14: 1,5-diazabicyclo[4.3.0]non-5-ene (for comparison) A-15: 1,1,3,3-tetramethylguanidine (for comparison)

[0155] Complexing agent: B-1: Citric Acid B-2: Malonic acid B-3: Tartaric acid B-4: Adipic acid B-5: Malic acid B-6: Glutaric acid B-7: Tartaric acid B-8: Succinic acid B-9: Glycine (for comparison) B-10: Etidronic acid (for comparison) B-11: Histidine (for comparison)

[0156] Dispersant: C-1: Vinylpyrrolidone homopolymer (Luviskol K17, manufactured by BASF; Mw-10000 g / mol) C-2: Phenolsulfonic acid condensate (Tamol DN) containing formaldehyde, phenol, urea, and sodium salt. C-3: Polyethylene glycol (Pluriol E1500 E, M w (1500g / mol) C-4: Acrylic resin (Joncryl 682; M w -1700g / mol; for comparison)

[0157] solvent: D-1: Water D-2: Ethylene glycol D-3: 1,2-Propylene Glycol D-4: Dimethyl sulfoxide (DMSO)

[0158] additives Reducing agent: E-1: D-Sorbitol E-2: Xylitol

[0159] Humectant: F-1: An alkoxylated, mainly unbranched fatty alcohol containing high molecular weight alkene oxide in addition to ethylene oxide (Plurafac LF401; viscosity of approximately 135 mPa·s at 25°C, measured at Brookfield 60 rpm). F-2:C8~C 10 Alkyl polyglucoside of fatty alcohol (Glucopon 225DK; viscosity at 23°C according to Brookfield LVT method based on EN 12092: approximately 4000 mPa·s) F-3: N-Oleyl Sarcosine (BASF Sarkosyl O)

[0160] composition The components of the composition were thoroughly mixed, and all mixing steps were carried out under stirring. The concentrate typically contained the following composition: approximately 10% by mass of pH adjuster, 0.5% by mass of complexing agent, 0.6% by mass of polymer dispersant, and optionally 3.5% by mass of reducing agent, 3.0% by mass of wetting agent, and 15.0% by mass of water-miscible solvent. Ultrapure water (UPW) was used to adjust the composition to 100% by mass. In etching experiments, the concentrated composition was diluted, usually by diluting it approximately 50 times, and this diluted composition was used. Tables 1 and 2 below provide further details of the compositions tested.

[0161] Static etching rate (SER) test Two cobalt and two copper blank wafer test specimens (2 × 2 cm each) were pre-etched with 1 mass% oxalic acid at room temperature for 1 minute. The specimens were rinsed with ultrapure water and dried in air. The thickness of the cobalt and copper layers on the specimens was measured using XRF. A suitable PCC formulation was heated to 60°C, and two cobalt blank wafer test specimens (2 × 2 cm) were immersed in the temperature-controlled solution for 3 minutes. The specimens were then rinsed with ultrapure water and dried in air. The same procedure was repeated with two copper blank wafer test specimens. The thickness of the wafer test specimens was measured using XRF. The static etching rate (SER) was calculated by dividing the difference in cobalt / copper layer thickness before and after PCC solution treatment by the etching time of 3 minutes.

[0162] Turbidity measurement (nephelometry) The turbidity of concentrated solutions and compositions diluted 50-fold was measured using a Hach Lange TL2350 instrument (Hach Lange GmbH). Scattered light from the samples was measured at a 90-degree angle to the incident light. Measurements were performed using white light (tungsten; wavelength = 340-850 nm). The nephelometer was calibrated using formazin standard solution. All samples with a turbidity of less than 1.3 NTU (NTU = nephelometric turbidity unit) were considered unturbid.

[0163] For further evaluation, diluted compositions were prepared in Tables 1 and 2 by appropriately diluting the concentrated compositions. The final concentrations of the compositions were as follows: 0.012% by mass of polymer dispersant, and optionally 0.07% by mass of reducing agent, 0.06% by mass of wetting agent, and 0.3% by mass of water-miscible solvent. Furthermore, all compositions contained pH adjusters at the concentrations listed below, and molar concentrations were also considered to ensure comparison of results between the various compositions. Similarly, the complexing agents described in the specification were added at the concentrations listed below to ensure comparability of the results due to differences in coordination numbers. The compositions were adjusted to 100% by mass using ultrapure water (UPW).

[0164] [Table 1]

[0165] [Table 2]

[0166] [Table 3]

[0167] [Table 4]

[0168] result Preferably, the SER value for copper is less than 4.0 and for cobalt it is less than 5.0. Surprisingly, Examples 1-19 in Table 1 showed low static etching rates for cobalt and copper. Also, as mentioned above, concentrated compositions are commercially important due to their ease of transport. However, at high concentrations, the overall compatibility and miscibility of the various essential components are poor. Examples 1-19 in Table 1 were easily processed without visible turbidity using a solvent (water, or a mixture of water and a water-soluble solvent such as ethylene glycol). Similar results were obtained when the compositions were prepared in concentrated form (for example, compositions containing about 10% by mass of a pH adjuster, with other components appropriately adjusted compared to the examples in Table 1). Similar results were confirmed when alternative water-mixable solvents such as propylene glycol (D-3) or DMSO (D-4) were used (see Examples 15-16 in Table 1). Optional components such as wetting agents were also tested, and acceptable results were obtained (Examples 17-19 in Table 1, including dispersants F-1-F-3). It was confirmed that the reducing agent is optional (see Example 1). However, it was also confirmed that the presence of a reducing agent yields acceptable results. Furthermore, when xylitol (E-2) was used as the reducing agent, replacing sorbitol (E-1) in Example 2 of Table 1, acceptable results were obtained in both SER and turbidity.

[0169] Replacing one or more essential components with components not conforming to the present invention resulted in undesirable effects. For example, Comparative Examples 1-3 and 11 in Table 2 contained compounds A-3-A-5 and A-13 instead of the pH adjuster according to the present invention, and it was confirmed that undesirable turbidity / precipitation occurred. Similar undesirable turbidity was observed in Comparative Example 17 in Table 2, which contained acrylic resin (C-4; dispersant). Careful selection of various important components (e.g., complexing agents and polymer dispersants) is essential to ensure low SER. Therefore, it is noteworthy that even when the complexing agent concentration was increased in Examples 4-11 (see Table 1), acceptable low SER was obtained.

[0170] Furthermore, when the composition did not conform to the present invention, undesirable high SER values ​​were observed for either copper or / or cobalt. For example, Comparative Examples 4-10, 12, and 13 in Table 2 contained pH adjusters that did not conform to the present invention (A-6-A-12, A14, and A15) and showed high SER values. Similarly, when complexing agents that did not conform to the present invention (B-9-B-11 included in Comparative Examples 14-16 in Table 2) were used in the composition, similar undesirable results were observed.

Claims

1. i) an alkaline composition for cleaning substrates containing copper or a copper alloy, and ii) cobalt or a cobalt alloy: a) At least one pH adjuster selected from the compounds of formula I. 【Chemistry 1】 (In the formula, Ra, Rb, Rd, and Rf are independent of each other, unsubstituted linear or branched C １ ~C １２ Selected from alkyl groups, Re is an unsubstituted linear or branched C ４ ~C ９ Selected from alkyl groups; however, the dashed bond between Re and N is either a single or double bond, and if the dashed bond is a double bond, Rd is absent. Ra, Rb, Re, and Rf combine to form one or more six-membered or seven-membered rings. b) C having at least two sulfonic acid groups or carboxylic acid groups ２ ~C １２ At least one complexing agent selected from hydrocarbons, c) At least one polymer dispersant having a mass-average molecular weight of 1000 g / mol or more; and d) A solvent containing water A composition containing the following:

2. Rc is an unsubstituted linear or branched C ２ ~C １２ The composition according to claim 1, selected from alkyl groups.

3. Ra, Rb, Rd and Rf are, independently of one another, unsubstituted linear or branched C １ -C ６ The composition according to claim 1 or 2, selected from alkyls.

4. The composition according to any one of claims 1 to 3, wherein the pH adjusting agent has a pKa of 9.0 or higher.

5. The composition according to any one of claims 1 to 4, wherein the dispersant is selected from polyvinylpyrrolidone, polyethylene oxide, ethylene oxide propylene oxide copolymer, naphthalene sulfonic acid formaldehyde condensate, phenol sulfonic acid formaldehyde condensate, or naphthalene sulfonic acid phenol sulfonic acid formaldehyde mixed condensate.

6. The composition according to any one of claims 1 to 5, wherein the complexing agent is selected from citric acid, tartaric acid, tartonic acid, malonic acid, succinic acid, glutaric acid, malic acid, or a mixture thereof.

7. A composition according to any one of claims 1 to 6, which is essentially free from triazoles, quaternary ammonium salts, alkanolamines, or derivatives thereof.

8. The composition according to any one of claims 1 to 7, wherein the solvent (d) is essentially water.

9. The composition according to any one of claims 1 to 8, wherein the pH is 7.5 to 14.

0.

10. a) pH adjuster in an amount of 0.02 to 40.0% by mass; b) 0.005 to 3.0% by mass of a complexing agent; c) 0.001% to 3.0% by mass of a polymer dispersant; and The remaining water-containing solvent A composition according to any one of claims 1 to 9, comprising:

11. A concentrated solution for preparing the composition according to any one of claims 1 to 10, a) 4.0 to 40.0% by mass of pH adjusting agent; b) 0.1 to 3.0% by mass of a complexing agent; c) 0.01% to 3.0% by mass of a polymer dispersant; and The remaining water-containing solvent A concentrated liquid containing [the specified ingredient].

12. A composition according to any one of claims 1 to 10 is made from a substrate including (i) a surface of cobalt or a cobalt alloy and (ii) a surface of copper or a copper alloy. (a) Post-etching residue (PERR) or post-ashing residue (PARR), (b) chemical mechanical planarization (CMP) residue; A method used to remove it.

13. A process for processing microelectronic devices, comprising the following steps: (a) a step of providing a microelectronic substrate having etching residue, ashing residue, or chemomechanical planarization (CMP) residue, including (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface; (b) a step of providing the composition according to any one of claims 1 to 10; (c) A step of bringing the composition into contact with (i) the surface of cobalt or a cobalt alloy and (ii) the surface of copper or a copper alloy for a time and temperature effective in removing at least partially, preferably completely, the etching residue, ashing residue, or chemomechanical planarization (CMP) residue from the substrate. A process that includes this.

14. A method for manufacturing a semiconductor device, comprising the process described in claim 13.

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