Composition for cleaning a substrate comprising cobalt and copper, use thereof and method

Abstract

The present invention relates to an alkaline composition for cleaning a substrate comprising a structure of copper or a copper alloy and a structure comprising cobalt or a cobalt alloy, the composition comprising: (a) 0.0001% to 0.2% by weight of a cobalt corrosion inhibitor selected from the group consisting of surfactants selected from the group consisting of (i) C10 to C20 alkyl sulfonic acids or C12 to C24 alkyl benzenesulfonic acids, and (ii) 0.01% to 0.2% by weight of a cobalt corrosion inhibitor selected from the group consisting of cobalt or cobalt; (ii) a C8 to C17 alkyl phosphonic acid or an aminophosphonic acid (I1) of formula I1 wherein RI1 is a C8 to C20 alkyl group, RI2 is selected from H, C1 to C6 alkyl groups and-XI1-P (O) (OH) 2, and XI1 is selected from C1 to C6 alkanediyl groups, (iii) a C12 to C18 alkyl carboxylic acid or sarcosine or cocoyl sarcosine (I2) of formula I2 wherein RI1 is a C12 to C20 alkyl group, RI3 is selected from H, C1 to C6 alkyl groups and-XI1-C (O)-OH, and XI1 is selected from C1 to C6 alkanediyl groups, (iv) C10 to C20 mono or dialkyl esters of phosphoric acids, (v) (v) C10 to C20 mono or dialkyl esters of phosphoric the alkyl groups of (i) to (iv) may be interrupted by one or more O or may comprise one or more double bonds, (v) salts of (i) to (iv); (b) from 0.0001% to 0.5% by weight of a copper corrosion inhibitor selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; the catalyst is 2, 5-methyl benzotriazole; the catalyst is tetrahydrobenzotriazole; and a methyl-benzotriazole-1-yl)-methyl-imino-diethanol, and a mixture thereof; (c) from 0.05% to 1% by weight of a C2 to C7 monoaminoalkanol; and (d) a solvent; wherein the solvent consists essentially of water. # imgabs0 #

Description

[0001] The present invention relates to a composition for cleaning substrates comprising a structure of copper or a copper alloy and a structure or a barrier or adhesion layer comprising cobalt or a cobalt alloy, the use thereof and a method thereof. Background Art

[0002] The manufacture of electrical devices, especially semiconductor integrated circuits (ICs); liquid crystal panels; organic electroluminescent panels; printed circuit boards; micromachines; DNA chips; microdevices and magnetic heads; ICs preferably having LSI (large scale integrated circuits) or VLSI (very large scale integrated circuits); and optical devices, especially optical glasses, such as photomasks, lenses and prisms; inorganic conductive films, such as indium tin oxide (ITO); optical integrated circuits; optical switching elements; optical waveguides; optical single crystals, such as the end faces of optical fibers 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 particularly include surface preparation using high-purity cleaning compositions, pre-weaving cleaning, post-etching cleaning and / or post-chemical polishing cleaning steps.

[0003] Special care must be taken when manufacturing ICs with LSI or VLSI. Semiconductor wafers used for this purpose include a semiconductor substrate (such as silicon) in which areas are patterned for the deposition of different materials with electrically insulating, conducting or semiconducting properties.

[0004] In order to obtain the correct patterning, the excess material used to form the different layers on the substrate must be removed. In addition, in order to manufacture practical and reliable ICs, it is very important to have a flat or planar semiconductor wafer surface. Therefore, during the manufacturing of ICs, it is necessary to clean, remove and / or polish certain surfaces of the semiconductor wafer before proceeding to the next process step.

[0005] Most processing operations involving wafer substrate surface preparation, deposition, plating, etching and chemical mechanical polishing require cleaning operations in one way or another to ensure that the ICs are free of contaminants that could otherwise adversely affect the functionality of the ICs or even render them incapable of performing their intended function.

[0006] A particularly serious problem is the residue left on the substrate after the CMP process. During, for example, Cu-CMP, the copper ion concentration may exceed the maximum solubility of the copper-inhibitor complex. As a result, the copper-inhibitor complex may precipitate from the solution and may solidify into surface residues. Moreover, these residues may stick to the surface of the polishing pad and accumulate to eventually fill the grooves in the polishing pad. In addition, abrasive particles and chemicals contained in the CMP slurry and reaction byproducts may remain on the wafer surface. In addition, polishing of copper damascene structures containing low-k or ultra-low-k dielectric materials (such as carbon-doped oxides or organic films) may produce carbon-rich particles that settle on the wafer surface. To make matters worse, these low-k or ultra-low-k dielectric materials and silicon carbide, silicon nitride or silicon oxynitride CMP stop layers are very hydrophobic and therefore difficult to clean with water-based cleaning solutions.

[0007] Another process that produces residues commonly found in IC manufacturing involves gas phase plasma etching, which transfers the pattern of the developed photoresist coating (used to form vias and trenches) to underlying layers, which may consist of hard mask, interlayer dielectric, etch stop layer. Gas phase plasma etch residues (which may contain chemical elements present on and in the substrate and in the plasma gas) are typically deposited on back-end-of-line (BEOL) structures and, if not removed, may interfere with subsequent silicidation and contact formation.

[0008] As device nodes shrink to less than 10 nanometers (nm) in advanced semiconductor manufacturing, new materials are introduced for better device performance and manufacturability. Examples of new materials under consideration include layers or features made of cobalt or cobalt alloys, such as through-hole contacts, cobalt barriers, etc. In the case of using cobalt metal, other materials may be necessary, such as adhesion layers. Here, for example, Ti, TiN or Ta, TaN and combinations of these materials can be used. A conductive copper-containing layer can be deposited on top of the cobalt barrier layer and form a feature (such as a copper trench or through hole).

[0009] Cleaning compositions compatible with cobalt and copper, such as post-etch residue removal (PERR) or post-CMP cleaning (PCC), enable manufacturing processes to be performed at smaller and more advanced nodes. In back-end-of-line (BEOL) processes, copper (Cu) is still used as interconnect metal lines, so cleaning chemical formulations compatible with copper as well as new materials are advantageous. For films (like Ti, TiN, Ta, TaN, Co, Cu), dielectric layers (like Si, SiN, SiO 2 There continues to be a need for cleaning compositions with controlled or suppressed etch rates and selectivities for ), low-k or high-k materials.

[0010] According to US 5 770 095, it is known to use BTA and its derivatives in compositions for chemical mechanical planarization (CMP) compositions to inhibit oxidation or corrosion of copper surfaces in the atmosphere or in solutions capable of corroding copper. US 2017 / 0158913A discloses a CMP composition for polishing cobalt or cobalt and copper and / or cobalt alloys, the composition comprising an amino acid and a diazole, triazole, tetrazole or a derivative thereof as a corrosion inhibitor.

[0011] US2018 / 0371371 A1 and US2019 / 002802 A disclose an aqueous post-CMP cleaning composition, which comprises polyethylene glycol, anionic polymer poly(acrylic acid), acrylic acid-maleic acid copolymer, polyaspartic acid, polyglutamic acid, polyvinylphosphonic acid, polyvinylsulfonic acid, poly(styrenesulfonic acid), polycarboxylate ether, polyphosphite, and copolymers of polymers thereof.

[0012] CN 106 957 748A discloses an aqueous circuit board cleaning composition comprising, for example, 3 wt % of sarcosine laurate, 0.6 wt % of benzotriazole, 5.5 wt % of monoethanolamine, organic solvents such as 7.7 wt % of dipropylene glycol butyl ether and 7.7 wt % of tripropylene glycol butyl ether, and 61.4 wt % of water.

[0013] CN 106 833 993A discloses a water-based cleaner comprising 50-70 wt % of water, 10-25 wt % of ethylene glycol, 10-20 wt % of propylene glycol, 5-10 wt % of an alcohol amine, 4-10 wt % of a surfactant, 0.2-1 wt % of a corrosion inhibitor, 0.5-1.5 wt % of a defoaming agent and 0.5-1 wt % of a stabilizer.

[0014] WO 2006 / 127885 A1 discloses an alkaline aqueous cleaning composition for cleaning post-chemical mechanical polishing (CMP) residues and contaminants from microelectronic devices, and a method for cleaning residues and contaminants from microelectronic devices. The composition specifically claimed contains, for example, 0.11 wt% dodecylbenzenesulfonic acid, 2 wt% 1,2,4 triazole, 9 wt% monoethanolamine, 3.5 wt% ascorbic acid and 85.39 wt% water. They are diluted 5:1 to 50:1.

[0015] US2003 / 130146 A1 discloses aqueous compositions for removing organic and inorganic residues as well as polymer residues and contaminants from semiconductor substrates after etching. These compositions are composed of a water-soluble organic solvent, sulfonic acid and water.

[0016] US2020 / 231900 A1 discloses cleaning liquids for semiconductor wafers, which contain polyoxyalkylene alkyl ether phosphoric acid and a chelating agent (such as tartaric acid). These cleaning liquids are used for cleaning after chemical mechanical polishing or cleaning after etching.

[0017] However, if the substrate includes metallization based on, for example, cobalt and copper (e.g., the cobalt-lined integrated solution described in US2012 / 0161320), and these surfaces can be in contact with cleaning solutions, care must be taken that the cleaning solutions are compatible with both metals. This is especially true for Cu-PCC and PERR solutions. For PERR, the metal structure is only open at the bottom of the through-hole, etching into the dielectric layer. But for post-Cu CMP, the upper surface of the metallization is completely exposed to the PCC solution. Since the metal or material showing metallic conductivity is in galvanic contact (cobalt-lined integrated solution) and immersed in the PERR or PCC cleaning solution, galvanic corrosion may also need to be considered. Examples of the metals involved can be Ru, Pt, Ir, Pd, Re, Rh, Ti, Ta, Mn, Ni, Al, Cr, V, Mo, Zr, Nb, W, Zr, Cu, their alloys, and conductive materials (like TiN and TaN). Cu can be a filling material.

[0018] The object of the present invention is to provide cleaning compositions for processing substrates which can be used in the manufacture of electrical devices, particularly semiconductor integrated circuits (ICs), which substrates include structures of copper or copper alloys and structures or barrier or adhesion layers comprising cobalt or cobalt alloys, which cleaning compositions show less corrosion to cobalt and copper surfaces on the substrates.

[0019] The cleaning composition should be particularly well suited for performing the cleaning steps mentioned above, in particular for post-CMP cleaning of semiconductor wafers during the manufacture of ICs with LSI or VLSI, in particular by copper damascene or dual damascene processes. The cleaning composition should most effectively remove various residues and contaminants generated during substrate surface preparation, deposition, plating, etching and CMP processes to ensure that the substrate, in particular the IC, is free of residues and contaminants that would otherwise adversely affect the function of electrical and optical devices, in particular the IC, or even render them unable to perform their intended functions. In particular, the cleaning composition should prevent the roughening of cobalt and copper metallization in damascene structures. Summary of the invention

[0020] It has now been found that the use of specific corrosion inhibitors in combination with monoaminoalkanols can significantly reduce copper and cobalt corrosion.

[0021] Thus, one embodiment of the present invention is an alkaline composition for cleaning a substrate comprising a structure of copper or a copper alloy and a structure comprising cobalt or a cobalt alloy, the composition comprising:

[0022] (a) 0.0001% to 0.2% by weight of a cobalt corrosion inhibitor selected from a surfactant selected from

[0023] (i)C 10 To C 20 Alkyl sulfonic acid or C 12 To C 24 Alkylbenzenesulfonic acid,

[0024] (ii)C 8 To C 17 Alkylphosphonic acid or aminophosphonic acid having formula I1

[0025]

[0026] in

[0027] R I1 It is C 8 To C 20 alkyl,

[0028] R I2 Selected from H, C 1 To C 6 Alkyl and -X I1 -P(O)(OH) 2 ,and

[0029] X I1 Selected from C 1 To C 6 Alkanediyl,

[0030] (iii)C 12 To C 18 Alkyl carboxylic acid or sarcosine or cocoyl sarcosine having formula I2

[0031]

[0032] in

[0033] R I1 It is C 12 To C 20 alkyl,

[0034] R I3 Selected from H, C 1 To C 6 Alkyl and -X I1 -C(O)-OH, and

[0035] X I1 Selected from C 1 To C 6 Alkanediyl,

[0036] (iv) Phosphoric acid C 10 To C 20 Mono- or di-alkyl esters,

[0037] These alkyl groups (i) to (iv) may be interrupted by one or more O or may contain one or more double bonds,

[0038] (v) Salts of (i) to (iv);

[0039] (b) 0.0001% to 0.5% by weight of a copper corrosion inhibitor selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; 5-methylbenzotriazole; tetrahydrobenzotriazole; and methyl-benzotriazol-1-yl)-methyl-imino-bisethanol;

[0040] (c) 0.05 to 1% by weight of C 2 To C 7 Monoaminoalkanols; and

[0041] (d) solvent;

[0042] Wherein the solvent consists essentially of water.

[0043] Another embodiment of the present invention is a concentrate for preparing a composition as described herein, the concentrate comprising:

[0044] (a) 0.01% to 5% by weight of the cobalt corrosion inhibitor;

[0045] (b) 0.01% to 1% by weight of the copper corrosion inhibitor;

[0046] (c) 1 to 20% by weight of the monoaminoalkanol;

[0047] (d) 0% to 20% by weight of one or more organic solvents; and

[0048] (e) Residue of water.

[0049] Yet another embodiment of the present invention is the use of a composition as described herein for removing from a substrate

[0050] (a) Post-etch residue (PERR) or post-ash residue (PARR), or

[0051] (b) Chemical Mechanical Planarization (CMP) residues,

[0052] The substrate includes (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface.

[0053] Yet another embodiment of the present invention is a method of processing a microelectronic device, the method comprising:

[0054] (a) providing a microelectronic substrate comprising (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface, the microelectronic substrate having post-etch residue, post-ash residue, or chemical mechanical planarization (CMP) residue thereon;

[0055] (b) providing a composition according to any one of claims 1 to 10; and

[0056] (c) contacting (i) the cobalt or cobalt alloy surface and (ii) the copper or copper alloy surface with the composition for a time and at a temperature effective to at least partially, and preferably completely, remove post-etch residue, post-ash residue, or chemical mechanical planarization (CMP) residue from the substrate.

[0057] In view of the prior art discussed above, it is surprising and not anticipated by the skilled artisan that the underlying objects of the present invention would be solved by the compositions and methods of the present invention.

[0058] What is particularly surprising is that 2 To C 6 The specific cobalt inhibitor as described herein of the monoaminoalkanol combination and a copper inhibitor selected from triazoles is associated with a synergistic effect with respect to cobalt and copper corrosion.

[0059] The composition of the invention is most particularly well suited for carrying out the above-mentioned cleaning steps, in particular post-CMP cleaning of semiconductor wafers and the manufacture of ICs with LSI or VLSI, in particular by copper damascene or dual damascene processes.

[0060] The compositions of the present invention are most effective in removing various residues and contaminants generated during substrate surface preparation, deposition, plating, etching and CMP processes, and ensure that substrates, especially ICs, are free of residues and contaminants that would otherwise adversely affect the function of electrical and optical devices, especially ICs, or even prevent them from performing their intended functions. In particular, they prevent scratching, etching and roughening of copper metallization in damascene structures. DETAILED DESCRIPTION

[0061] The compositions of the present invention are aqueous alkaline cleaning compositions useful in processing substrates that are useful in the manufacture of electrical and optical devices.

[0062] definition

[0063] "Aqueous" means that the compositions of the present invention contain water. The water content of different compositions may vary greatly.

[0064] "Solvent consisting essentially of water" preferably means that the total amount of any solvent other than water in the composition, in particular the amount of one or more water-miscible organic solvents, is about 1% by weight or less, more preferably about 0.5% by weight or less, most preferably about 0.3% by weight or less, based on the total weight of the composition.

[0065] By "alkaline" it is meant that the composition of the present invention has a pH in the range of 7.5 to 14, preferably 9 to 13, and more preferably 9.5 to 12.5, even more preferably 10 to 12, most preferably 10.5 to 11.5.

[0066] "Chemical bond" means that the corresponding moieties do not exist but the adjacent moieties are bridged so as to form a direct chemical bond between these adjacent moieties. For example, if in the molecule ABC the moiety B is a chemical bond, then the adjacent moieties A and C together form a group AC.

[0067] "Copper inhibitor" means a compound that inhibits the static removal of copper from a substrate by etching. "Cobalt inhibitor" means a compound that inhibits the static removal of cobalt from a substrate by etching.

[0068] The term "C x " means that the corresponding group contains x number of C atoms. The term "C x To C y "Alkyl" means an alkyl group having from x to y carbon atoms and, unless expressly specified, includes unsubstituted straight chain, branched chain and cyclic alkyl groups. In the context of alkyl carboxylic acid corrosion inhibitors, C x To C y Alkyl means an alkyl group excluding the "C" atoms of the carboxyl functional group.

[0069] As used herein, "alkanediyl" refers to a diradical of a linear, branched or cyclic alkane or a combination thereof.

[0070] By "structure" herein is meant a structure made of the corresponding material, such as but not limited to a structured or continuous layer of a material.

[0071] Unless otherwise indicated, all percentages, ppm or similar values ​​refer to weight relative to the total weight of the corresponding composition. The term wt% means % by weight.

[0072] All cited documents are incorporated herein by reference.

[0073] Cobalt Corrosion Inhibitors

[0074] The cleaning composition according to the invention comprises an anionic surfactant as cobalt inhibitor.

[0075] In a first embodiment, the cobalt corrosion inhibitor is C 10 To C20 Alkyl sulfonic acid or C 12 To C 24 Alkylbenzene sulfonic acid. Without limitation, C 10 To C 20 Examples of alkylsulfonic acids are 1-dodecylsulfonic acid, 1-tridecylsulfonic acid, 1-tetradecylsulfonic acid, 1-pentadecylsulfonic acid, 1-hexadecylsulfonic acid, 1-heptadecylsulfonic acid, 1-octadecylsulfonic acid, 1-nonadecylsulfonic acid, and mixtures thereof. Without limitation, C 12 To C 24 Examples of alkylbenzenesulfonic acids are dodecylbenzenesulfonic acid, 4-tridecylbenzenesulfonic acid, 4-tetradecylbenzenesulfonic acid, 4-pentadecylbenzenesulfonic acid, 4-hexadecylbenzenesulfonic acid, and mixtures thereof.

[0076] In a second embodiment, the cobalt corrosion inhibitor is C 8 To C 17 Alkylphosphonic acid or aminophosphonic acid having formula I1

[0077]

[0078] in

[0079] R I1 It is C 8 To C 20 Alkyl, preferably C 10 To C 18 alkyl;

[0080] R I2 Selected from H, C 1 To C 6 Alkyl and -X I1 -P(O)(OH) 2 , preferably selected from H, C 1 To C 4 Alkyl and -X I1 -P(O)(OH) 2 , most preferably -X I1 -P(O)(OH) 2 ;and

[0081] X I1 Selected from C 1 To C 6 Alkanediyl, preferably selected from C 1 To C 4 Alkanediyl, most preferably selected from methanediyl and ethanediyl.

[0082] A particularly preferred alkylphosphonic acid type cobalt corrosion inhibitor is octadecylphosphonic acid.A particularly preferred cobalt corrosion inhibitor having formula I1 is an N-cocoalkyl derivative of iminobis(methylene)bisphosphonic acid.

[0083] In a third embodiment, the cobalt corrosion inhibitor is C 12 To C 18 Alkyl carboxylic acid, sarcosine or cocoyl sarcosine (C 7 To C 17 Alkyl Sarcosine Mixture)

[0084]

[0085] in

[0086] R I1 It is C 12 To C 20 alkyl,

[0087] R I3 Selected from H, C 1 To C 6 Alkyl and -X I1 -C(O)-OH, preferably selected from H and C 1 To C 4 alkyl, most preferably methyl, ethyl or propyl, and

[0088] X I1 Selected from C 1 To C 6 Alkanediyl, preferably selected from C 1 To C 4 The alkyl group is most preferably selected from methanediyl, ethanediyl and propanediyl.

[0089] The compound of formula I2 can be used as a single compound or as a mixture of compounds. 12 To C 18 Alkyl carboxylic acid corrosion inhibitors are myristic acid, palmitic acid, stearic acid, palmitoleic acid, elaidic acid, linoleic acid, and mixtures thereof. A preferred corrosion inhibitor having formula I1 is N-cocoyl sarcosine (C 7 To C 17 mixture of alkyl sarcosine) and N-oleoyl sarcosine (C 12 alkyl sarcosine).

[0090] In a fourth embodiment, the cobalt inhibitor is C of phosphoric acid. 6 To C 20 Mono- or di-alkyl esters, preferably C 6 -C 10 Mono- or di-alkyl esters.

[0091] In all embodiments, the alkyl groups of (i) to (iv) may optionally be interrupted by one or more O, preferably one or two O. Most preferably, these alkyl groups are not interrupted by any O atoms.

[0092] In all embodiments, the alkyl group of (i) to (iv) may optionally contain one or more double bonds, preferably one or two double bonds. Most preferably, the alkyl group does not contain any double bonds.

[0093] Alternatively, the corresponding salts of compounds (i) to (iv) may be used. The counterion may be any cation that does not interfere with the substrate.

[0094] The cobalt corrosion inhibitor may be used in an amount of about 0.0001% to about 0.2% by weight, preferably about 0.001% to about 0.15% by weight, more preferably about 0.002% to about 0.1% by weight, most preferably about 0.005% to about 0.05% by weight, based on the total weight of the composition.

[0095] Copper Corrosion Inhibitors

[0096] The cleaning composition according to the present invention comprises a copper corrosion inhibitor.

[0097] The copper corrosion inhibitor is selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; 5-methylbenzotriazole; tetrahydrobenzotriazole; and methyl-benzotriazol-1-yl)-methyl-imino-bisethanol.

[0098] The copper corrosion inhibitor may be used in an amount of about 0.0001% to about 0.5% by weight, preferably about 0.001% to about 0.3% by weight, more preferably about 0.002% to about 0.1% by weight, most preferably about 0.002% to about 0.05% by weight, based on the total weight of the composition.

[0099] The compositions according to the present invention (comprising the etchant in the preferred total amounts defined herein) have shown excellent suppression of the static etch rates of cobalt and copper.

[0100] Monoaminoalkanol

[0101] The composition according to the present invention further comprises C 2 To C 7 Monoaminoalkanol to adjust the alkaline pH of the dominant aqueous solution. The pH adjuster should not significantly corrode the metal (e.g., cobalt) or leave any residue on the treated surface. This can be assessed by static etch rate and subsequent visual inspection of processed metal-coated wafer coupons. Examples of organic amines are primary, secondary, or tertiary amines.

[0102] The monoamine contains one or more hydroxyl groups and optionally one or more ether groups. Examples are 2-(2-aminoethoxy)ethanol (diglycolamine), diethanolamine, monoethanolamine, triethanolamine, diisopropanolamine, 2-amino-1-propanol, triisopropanolamine, 3-dimethylaminopropan-1-ol, butyldiethanolamine, dibutylethanolamine, ethylethanolamine, dimethylethanolamine, N-methyl-diethanolamine, methyldiisopropanolamine, N,N-dimethylethanolamine, N,N-dimethylisopropanolamine, N-methylethanolamine, 3-amino-1-propanol, triisopropanolamine, 3-dimethylaminopropan-1-ol, butyldiethanolamine, dibutylethanolamine, ethylethanolamine, dimethylethanolamine, N-methyl-diethanolamine, methyldiisopropanolamine, N,N-dimethylethanolamine, N,N-dimethylisopropanolamine, N-methylethanolamine, 3-amino-1 -propanol, 4-(2-hydroxyethyl)morpholine, 5-amino-1-pentanol, 2-[2-(dimethylamino)ethoxy]ethanol, 2-dimethylamino-2-methyl-1-propanol, 2-methylamino-2-methyl-1-propanol, 1-amino-2-propanol (alaninol), 2-amino-1-methylpropanol (AMP), 4-amino-1-butanol, 3-amino-1,2-propanediol, diisopropanolamine, 2-methoxy-ethylamine, and combinations thereof.

[0103] More preferably, C 3 To C 6 Monoaminoalkanols, such as but not limited to 2-amino-1-propanol, 3-amino-1-propanol, 1-amino-2-propanol, 2-amino-1-methylpropanol (AMP), 2-methyl-aminoethanol, 3-amino-1,2-propanediol.

[0104] In a preferred embodiment, C 3 To C 6 Monoaminoalkanol is a compound having the formula A1

[0105] H 2 NX A -OH(A1)

[0106] Where X A Selected from linear or branched C 3 To C 5 , especially C 3 To C 4 Alkanediyl.

[0107] In a particularly preferred embodiment, C 3 To C 6 The monoaminoalkanol is selected from 2-amino-ethane-1-ol, 2-amino-propan-1-ol, 3-amino-propan-1-ol, 3-amino-propan-2-ol, 2-amino-1-methyl-propan-1-ol, 3-amino-1-methyl-propan-1-ol, 2-amino-2-methyl-propan-1-ol; 2-amino-butan-1-ol, 3-amino-butan-1-ol, 4-amino-butan-1-ol, 2-amino-3-methyl-butan-1-ol, 4-amino-2-methyl-butan-1-ol, 3-amino-1-methyl-butan-1-ol.

[0108] C 3 To C 6 The monoaminoalkanol may generally be used in an amount of about 0.04% to about 1% by weight, preferably 0.05% to 0.8% by weight, even more preferably 0.8% to 0.5% by weight, most preferably 0.1% to 0.3% by weight.

[0109] Solubilizer

[0110] In some embodiments, particularly for post-etch residue removal, the cleaning composition may optionally contain one or more water-miscible organic solvents different from any of the components defined above, particularly different from the monoaminoalkanol, particularly for post-etch residue removal, in an amount of about 1% by weight or less.

[0111] Such water-miscible organic solvents may preferably be selected from the group consisting of tetrahydrofuran (THF), N-methylpyrrolidone (NMP), dimethylformamide (DMF), dimethyl sulfoxide (DMSO), ethanol, isopropanol (IPA), butyl diglycol, butyl glycol, sulfolane (2,3,4,5-tetrahydrothiophene-1,1-dioxide), 1,3-dioxolane, propylene glycol; ethylene glycol, diethylene glycol, glycerol, 1,4-dioxane, γ-butyrolactone, acetonitrile and mixtures thereof; more preferably selected from the group consisting of THF, NMP, DMF, DMSO, sulfolane, 1,3-dioxolane, propylene glycol, diethylene glycol, ethylene glycol, glycerol, γ-butyrolactone and mixtures thereof. Most preferably, the water-miscible organic solvent may be selected from the group consisting of THF, DMSO, IPA, propylene glycol, diethylene glycol, ethylene glycol, glycerol, γ-butyrolactone and mixtures thereof.

[0112] In the context of the present invention, the term "water-miscible organic solvent" preferably means that an organic solvent meeting this requirement is miscible with water at least in a 1:1 (w / w) ratio at 20° C. and ambient pressure. Preferably, the or at least one water-miscible organic solvent is DMSO, ethylene glycol, gamma butyrolactone, sulfolane, IPA or propylene glycol. In particular, a preferred post-CMP cleaning composition is a composition according to the present invention that does not comprise one or more water-miscible organic solvents.

[0113] In individual cases, a composition as defined herein according to the present invention (or a preferred composition according to the present invention as described above or below) is preferred, wherein the total amount of one or more water-miscible organic solvents (i.e. the solvent component) is present in an amount of from about 0.01% to about 1% by weight, preferably from about 0.1% to about 1% by weight, more preferably from about 0.2% to about 1% by weight, even more preferably from about 0.1% to about 0.5% by weight, and even more preferably from about 0.3% to about 0.5% by weight or from about 0.03% to about 0.3% by weight, based on the total weight of the composition.

[0114] Dispersants

[0115] The composition may further comprise one or more dispersants for dispersing particulate organic, metallo-organic or inorganic residues.

[0116] A dispersant is a compound that can stabilize particles in a solvent (water) sterically, electrosterically or electrostatically. The dispersant can be a surfactant or a polymer or a mixture thereof. The dispersant must be soluble in the solvent system at the adjusted pH. This can be assessed by turbidity measurements, which are preferably performed at the process temperature at which the formulation is used commercially. For post-CMP cleaning, this is typically room temperature. If the formulation contains a surfactant as a dispersant, the surfactant can be a nonionic, zwitterionic or cationic surfactant. Among these surfactants, nonionic surfactants are preferred.

[0117] If the formulation comprises a polymer as a dispersant, the polymer may be anionic, zwitterionic, nonionic or cationic polymers. Among these polymers, anionic and nonionic polymers are preferred. These polymers may be homopolymers or copolymers from anionic or nonionic monomers.

[0118] The monomer may be ethylene oxide, propylene oxide, styrene, vinyl pyrrolidone, acrylamide, amino acids, carbohydrates, vinyl alcohol, acrylic acid, malonic acid, methacrylic acid, vinyl sulfonic acid, vinyl phosphonic acid, formaldehyde, phenol sulfonic acid, naphthalene sulfonic acid.

[0119] Preferred polymers are polyacrylic acid, polymalonic acid, acrylic acid-malonic acid copolymers, acrylic acid-styrene copolymers, acrylic acid-methacrylic acid copolymers, polyvinyl pyrrolidone, polyethylene oxide, ethylene oxide-propylene oxide copolymers, naphthalenesulfonic acid-formaldehyde condensates, phenolsulfonic acid-formaldehyde condensates, and naphthalenesulfonic acid-phenolsulfonic acid-formaldehyde mixed condensates.

[0120] The mass average molar mass M of the polymer wBelow 500 000 g / mol, preferably below 100 000 g / mol, even more preferably below 10 000 g / mol.

[0121] A portion of the dispersant is, for example, adsorbed on the surface of the particles to be dispersed. Another portion of the dispersant, for example, passes from the particles into the solution. Literature on the structure of adsorbed polymers is well known in the art and can be found, for example, in Lipatov and Sergeeva, Adsorption of Polymers, 1974. A portion of the dispersant in the solvent supports that the particles can be rinsed off the surface of the substrate to be cleaned. Improved interaction with the solvent will also increase the barrier between two particles or between a particle and the substrate surface to ensure that no agglomeration or redeposition occurs.

[0122] The chemical nature of the solvating part and the part adsorbed on the particle surface can be the same or different. Simulated dispersion mechanisms and dispersants are well known in the art and are described in, for example, TFTadros, Applied Surfactants—Principles and Application, first edition 2005, Chapter 7.

[0123] Complexing agent

[0124] The cleaning compositions, especially post-CMP cleaning compositions, may optionally contain one or more complexing agents.

[0125] Complexing agents are well known in the art.

[0126] Typically, the complexing agent in the liquid medium can dissolve metal salts or prevent the dissolved metal ions from forming insoluble precipitates by forming soluble complexes with the metal ions. The complexing agent is a non-polymer molecule comprising at least one functional acidic group, which can form a negatively charged group when the functional acidic group is deprotonated. This functional group can be a carboxylic acid, sulfonic acid or phosphonic acid group. The complexing agent can further include one or more N donors (like amine or pyridine type N), or phenolic OH groups for complexing metal ions. The complexing agent can include other functional groups, like hydroxyl or chlorine, etc.

[0127] Examples of complexing agents are carboxylic acids, such as but not limited to formic acid, acetic acid, propionic acid, or hydroxycarboxylic acids, such as but not limited to glycolic acid, lactic acid, glucuronic acid, etc. Another example is a polycarboxylic acid, such as but not limited to malonic acid, succinic acid, glutaric acid, hydroxymalonic acid, malic acid, tartaric acid, glucaric acid, citric acid, etc. Another example is an aminocarboxylic acid, such as but not limited to glycine, alanine, serine, proline, valine, glutamic acid, aspartic acid, imino-bis-succinic acid, 1,2-cyclohexylidene dinitrilo tetraacetic acid, ethylenediaminetetraacetic acid or nitrilotriacetic acid, etc. Another example is pyridine carboxylic acid and derivatives, such as but not limited to picolinic acid or dimerized picolinic acid, etc. Another example is phenol-carboxylic acid derivatives, such as but not limited to salicylic acid, etc. Another example is sulfonic acid, such as but not limited to methanesulfonic acid, etc. Another example is amino-sulfonic acid, such as but not limited to, for example, amino-ethanesulfonic acid (taurine), sulfoalanine, etc. Further examples are phenolsulfonic acid derivatives, such as but not limited to sulfosalicylic acid, etc. Further examples are phosphonic acids, like methylphosphonic acid, phosphonobutane-tricarboxylic acid (PBTC), etc. Further examples are polyphosphonic acids, such as but not limited to etidronic acid, etc. Further examples are aminophosphonic acids, such as but not limited to amino-trimethylenephosphonic acid (ATMP) or diethylene-triamine-penta(methylenephosphonic acid) (DTMP), ethylenediaminetetra(methylenephosphonic acid) (EDTMP), etc. Mixtures of the above complexing agents may also be used.

[0128] Preferred complexing agents are C optionally with one or more additional functional hydroxyl groups. 2 To C 6 Polycarboxylic acids. Particularly preferred complexing agents are oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, tartronic acid, malic acid, citric acid and tartaric acid.

[0129] A more preferred complexing agent is C 2 To C 6 Hydroxy-polycarboxylic acids. Particularly preferred complexing agents are tartronic acid, malic acid, citric acid and tartaric acid.

[0130] The most preferred complexing agent is citric acid.

[0131] Preferably, the one or more complexing agents are present in an amount of about 0.001% to about 0.1% by weight, preferably about 0.02% to about 1% by weight, more preferably about 0.05% to about 0.8% by weight, based on the total weight of the composition.

[0132] reducing agent

[0133] There may be oxidizing agents like H from previous process steps (e.g. CMP or etching steps). 2 O 2, persulfate or periodate residues, which may cause corrosion of small metal features on the wafer during subsequent cleaning steps. To prevent this, a catalyst that can be oxidized by oxidants such as H 2 O 2 The invention relates to reducing agents which are oxidized by iodine, persulfate or periodate. Examples of such reducing agents are 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.

[0134] A preferred reducing agent type is a saturated organic compound comprising at least four alcoholic hydroxyl groups, one of which is a primary hydroxyl group. A preferred reducing agent is pentaerythritol, tetrahydroxybutane, pentahydroxypentane, hexahydroxyhexane, 1,4-sorbitan, etc. The compound can, for example, form an acetal compound with a carbohydrate (like isomalt), or can be a free molecule (like mannitol). A preferred reducing agent type is a sugar alcohol comprising at least four hydroxyl groups. Examples of such sugar alcohols are sorbitol, arabitol, arabitol, isomalt, mannitol, threitol, erythritol, xylitol, or lactitol. The compound can, for example, form an acetal compound with a carbohydrate (like isomalt), or can be a free molecule (like mannitol).

[0135] A particularly preferred reducing agent is sorbitol.

[0136] Oxygen scavengers

[0137] Ambient oxygen dissolved in the solvent may already be able to damage small metal patterns on the substrate. To prevent this, an oxidizing agent like O can be added. 2 Oxidative oxygen scavengers.

[0138] Oxygen scavengers are unsaturated organic compounds containing at least one C-C double bond. The double bond may be isolated or part of a conjugated or aromatic system. Preferred types of oxygen scavengers are furanones and their derivatives, such as, for example, 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 isoascorbic acid. More preferred are furanones derivatives containing at least two OH-groups in the furanone ring, such as ascorbic acid or isoascorbic acid. Particularly preferred is ascorbic acid.

[0139] Another preferred type of oxygen scavenger is phenol derivatives. Examples are tyrosine, dihydroxybenzene, its isomers hydroquinone, catechol and resorcinol and derivatives like 4-methoxyphenol (MeHQ), trihydroxybenzene, its isomers like pyrogallol and phloroglucinol and derivatives like gallic acid or tannic acid type compounds, tetrahydroxybenzene, its isomers and derivatives.

[0140] Composition

[0141] The pH of the cleaning composition is from 7.5 to 12, preferably from 8 to 11.5, even more preferably from 9 to 11.4, most preferably from 9.6 to 11.2.

[0142] The solvent consists essentially of water.

[0143] In a preferred embodiment, the composition does not contain any organic solvents (except those which are the monoalkanolamines according to the invention) besides water, in particular does not contain any alkylene glycols, polyalkylene glycols, ethers or polyethers, DMSO or NMP.

[0144] In another preferred embodiment, the composition comprises the solvent as described above as a solubilizer in an amount of 1% by weight or less.

[0145] Preferably, the composition is substantially free of any particles, in particular silica particles. Substantially free means here that the composition does not contain any amount of particles that affect the cleaning function of the composition. Preferably, the particle content is less than 10ppm, more preferably less than 1ppm, most preferably less than the detection limit. In a preferred embodiment, the composition is filtered before use.

[0146] Preferably, the composition is substantially free of any oxidizing agent, in particular any peroxide. Substantially free here means that the composition does not contain any amount of active added oxidizing agents that increase copper or cobalt corrosion, but specifically excludes ambient oxygen (O 2 Preferably, the oxidizing agent content in the cleaning composition (except O 2 Most preferably, any oxidant (except O 2 The content of the above substances was below the detection limit.

[0147] Particularly preferred is a post-CMP composition according to the invention as defined herein, wherein the composition consists of

[0148] (a) 0.0001% to 0.2% by weight of a cobalt inhibitor selected from an anionic surfactant comprising (A) (i) a sulfonic acid, (ii) a phosphonic acid, (iii) a carboxylic acid, (iv) a phosphoric acid functional group, or (v) a salt thereof; and (B) C 10 To C 30 Alkyl, which may be interrupted by one or more O;

[0149] (b) 0.0001% to 0.5% by weight of a copper inhibitor selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; 5-methylbenzotriazole; tetrahydrobenzotriazole; and methyl-benzotriazol-1-yl)-methyl-imino-bisethanol;

[0150] (c) 0.05 to 1% by weight of C 2 To C 6 Monoaminoalkanol;

[0151] (d) water;

[0152] Above as defined herein and will be defined based on examples; all above based on the total weight of the composition, wherein the pH of the composition is from about 7.5 to about 12, preferably from about 9 to about 11.5, and wherein in each case the amount % of the components add up to 100% by weight. The concentrations of components (a) to (d) may vary within the preferred ranges described above.

[0153] Particularly preferred is a post-CMP composition according to the invention as defined herein, wherein the composition consists of

[0154] (a) 0.0001% to 0.2% by weight of a cobalt inhibitor selected from an anionic surfactant comprising (A) (i) a sulfonic acid, (ii) a phosphonic acid, (iii) a carboxylic acid, (iv) a phosphoric acid functional group, or (v) a salt thereof; and (B) C 10 To C 30 Alkyl, which may be interrupted by one or more O;

[0155] (b) 0.0001% to 0.5% by weight of a copper inhibitor selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; 5-methylbenzotriazole; tetrahydrobenzotriazole; and methyl-benzotriazol-1-yl)-methyl-imino-bisethanol;

[0156] (c) 0.05 to 1% by weight of C 2 To C 6 Monoaminoalkanol;

[0157] (d) water;

[0158] (e) 0% to 0.5% by weight of a water-miscible organic solvent;

[0159] The above are as defined herein and will be defined based on examples; all of the above are based on the total weight of the composition, wherein the pH of the composition is from about 7.5 to about 12, preferably from about 9 to about 11.5, and wherein in each case the amount % of the components add up to 100% by weight. The concentrations of components (a) to (e) may vary within the preferred ranges described above.

[0160] Particularly preferred is a post-etch residue removal composition according to the present invention as defined herein, wherein the composition consists of

[0161] (a) 0.0001% to 0.2% by weight of a cobalt inhibitor selected from an anionic surfactant comprising (A) (i) a sulfonic acid, (ii) a phosphonic acid, (iii) a carboxylic acid, (iv) a phosphoric acid functional group, or (v) a salt thereof; and (B) C 10 To C 30 Alkyl, which may be interrupted by one or more O;

[0162] (b) 0.0001% to 0.5% by weight of a copper inhibitor selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; 5-methylbenzotriazole; tetrahydrobenzotriazole; and methyl-benzotriazol-1-yl)-methyl-imino-bisethanol;

[0163] (c) 0.05 to 1% by weight of C 2 To C 6 Monoaminoalkanol;

[0164] (d) water;

[0165] (e) 0.01% to 1% by weight of a water-miscible organic solvent;

[0166] The above are as defined herein and will be defined based on examples; all of the above are based on the total weight of the composition, wherein the pH of the composition is from about 7.5 to about 12, preferably from about 9 to about 11.5, and wherein in each case the amount % of the components add up to 100% by weight. The concentrations of components (a) to (e) may vary within the preferred ranges described above.

[0167] The compositions of the present invention can be prepared by conventional and standard mixing methods, and mixing instruments such as stirred vessels, in-line dissolvers, high shear impellers, ultrasonic mixers, homogenizer nozzles or countercurrent mixers can be used to mix the components of the composition in the desired amounts.

[0168] It will be appreciated that it is common practice to prepare a concentrated form of the composition to be diluted prior to use. For example, the composition may be manufactured in a more concentrated form and thereafter diluted with water, at least one oxidizing agent, or other components at the manufacturer prior to and / or during use. The dilution ratio may range from about 0.1 parts diluent to 1 part composition concentrate to about 100 parts diluent to 1 part composition concentrate.

[0169] The composition can be prepared in particular by diluting a concentrate comprising:

[0170] (a) 0.01% to 5% by weight of the cobalt corrosion inhibitor;

[0171] (b) 0.01% to 1% by weight of the copper corrosion inhibitor;

[0172] (c) 1 to 20% by weight of the monoaminoalkanol;

[0173] (d) 0% to 20% by weight of one or more organic solvents; and

[0174] (e) Residue of water.

[0175] Preferred dilution factors (by volume) are from about 10 to about 100, preferably from about 20 to about 80, most preferably from about 25 to about 60.

[0176] application

[0177] The compositions of the present invention are well suited for the methods of the present invention.

[0178] However, the main purpose of the method of the present invention is to process substrates that can be used to manufacture electrical devices, especially semiconductor integrated circuits (ICs), liquid crystal panels; organic electroluminescent panels; printed circuit boards; micromachines; DNA chips; microdevices and magnetic heads; more preferably ICs with LSI (large-scale integrated circuits) or VLSI (very large-scale integrated circuits); and optical devices, especially optical glasses, such as photomasks, lenses and prisms; inorganic conductive films, such as indium tin oxide (ITO); optical integrated circuits; optical switching elements; optical waveguides; optical single crystals, such as the end faces of optical fibers and scintillators; solid-state laser single crystals; sapphire substrates for blue laser LEDs; semiconductor single crystals; and glass substrates for magnetic disks.

[0179] Preferably, the method of the present invention comprises a surface preparation, a pre-weaving cleaning, a post-etch cleaning or a post-CMP cleaning step, in particular a post-etch or post-CMP cleaning step.

[0180] The cleaning composition is particularly useful for removing

[0181] (a) Post-etch residue (PERR) or post-ash residue (PARR), or

[0182] (b) Chemical Mechanical Planarization (CMP) residues,

[0183] The substrate includes (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface.

[0184] The method of the present invention is particularly well suited for processing substrates which can be used to manufacture ICs having LSI or VLSI, and in particular can be used for back-end-of-line (BEOL) processing.

[0185] The method of the invention is most particularly well suited for post-CMP cleaning of semiconductor wafers in the manufacture of ICs with LSI or VLSI, in particular by copper damascene or dual damascene processes.

[0186] Thus, one embodiment relates to a kit comprising one or more components suitable for forming the compositions described herein in one or more containers. Preferably, one container comprises at least one oxidizing agent and a second container comprises the remaining components for combination at the manufacturing plant or point of use, e.g., at least one etchant, at least a selectivity enhancer, water, and optionally other components described herein.

[0187] In the use of the compositions described herein, the compositions are typically contacted with the device structure for a sufficient time of about 25 seconds to about 200 minutes, preferably about 5 minutes to about 60 minutes, at a temperature in the range of about 10° C. to about 80° C., preferably about 20° C. to about 60° C. Such contact times and temperatures are illustrative, and any other suitable time and temperature conditions effective to achieve the desired removal selectivity may be employed.

[0188] After achieving the desired cleaning action, the composition can be readily removed from the microelectronic device to which it has been previously applied, for example, by rinsing, washing, or one or more other removal steps as may be desired and effective in a given end-use application of the composition of the invention. For example, the device may be rinsed with a rinse solution comprising deionized water, an organic solvent, and / or dried, for example, by spin drying, N 2 , steam drying, etc.

[0189] The cleaning compositions described herein can be advantageously used for post-etch or post-ashing residue removal (PERR, PARR), post-CMP cleaning, surface preparation, and pre-metal plating cleaning of substrates, particularly including both cobalt or cobalt alloy surfaces and copper or copper alloy surfaces.

[0190] The cleaning composition described herein can be advantageously used in a method for manufacturing a semiconductor device, the method comprising the steps of

[0191] (a) providing a microelectronic substrate comprising (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface, the microelectronic substrate having post-etch residue, post-ash residue, or chemical mechanical planarization (CMP) residue thereon;

[0192] (b) providing a composition according to any one of claims 1 to 10;

[0193] (c) contacting (i) the cobalt or cobalt alloy surface and (ii) the copper or copper alloy surface with the composition for a time and at a temperature effective to at least partially remove post-etch residue, post-ashing residue, or chemical mechanical planarization (CMP) residue from the substrate.

[0194] Preferably, post-etch residues, post-ash residues, or chemical mechanical planarization (CMP) residues are completely removed from the substrate.

[0195] The following examples shall further illustrate the present invention without limiting the scope of the present invention.

[0196] Examples

[0197] The etch rate experiment was performed as follows:

[0198] Two cobalt blank wafer samples and two copper blank wafer samples (2×2 cm each) were pre-etched in 1 wt.% oxalic acid for 1 min each. The samples were rinsed with water and dried in air. The thickness of the cobalt and copper levels on the samples was determined by XRF.

[0199] The ready-to-use PCC formulation was heated to 60°C and two cobalt blank wafer specimens (2×2 cm) were immersed in the tempering solution for 3 min. The specimens were then rinsed with ultrapure water and dried in air. The same procedure was repeated with two copper blank wafer specimens. The thickness of the wafer specimens was determined by XRF. The static etching rate was determined by calculating the difference in cobalt / copper horizontal thickness before and after PCC solution treatment divided by the etching time of 3 min.

[0200] The following materials were used in electronic grade purity. All amounts given for the compounds in the compositions are absolute amounts in the entire mixture, ie excluding any water.

[0201] Cobalt Corrosion Inhibitors:

[0202] A-1 Dodecylbenzenesulfonic acid

[0203] A-2 Mono- and di-C phosphate 6 -C 10 -Alkyl ester

[0204] A-3 ([Iminobis(methylene)]bisphosphonic acid, N-coconut-alkyl derivative) ammonium salt

[0205] A-4 N-Cocoyl Sarcosine (C 8 To C 18 Alkyl Sarcosine Mixture)

[0206] A-5 N-oleoylsarcosine (C 17 Alkyl Sarcosine)

[0207] A-6 Octadecylphosphonic acid (insoluble, comparative)

[0208] A-7 N-lauroyl sarcosine (C 11 Alkyl Sarcosine) (Comparison)

[0209] A-8 Ethoxylated C 10 Guerbet alcohol R 1 R 2 -C-CH 2 O(CH 2 -CH 2 O) n R 3 H(n=8)(Comparison)

[0210] A-9 Alkyl Polysaccharide (Comparison)

[0211] A-10 4-Butyl-benzoyl-sarcosine (Comparison)

[0212] A-11 Lauric acid (comparison)

[0213] Copper Corrosion Inhibitors:

[0214] B-1 Benzotriazole (BTA)

[0215] B-2 5-Chlorobenzotriazole (5-Cl BTA)

[0216] B-3 4,5,6,7-Tetrahydro-1H-benzotriazole

[0217] B-4 1,2,3 triazole (comparative)

[0218] B-5 5-phenyl-tetrazolyl (comparative)

[0219] B-6 Imidazole (Comparison)

[0220] B-7 Benzimidazole (Comparison)

[0221] B-8 Uric Acid (Comparison)

[0222] B-9 Isophthalic acid (comparison)

[0223] C 2 To C 7 Monoaminoalkanol:

[0224] C-1 2-Amino-2-methyl-propan-1-ol

[0225] C-2 Triethanolamine

[0226] C-3 Diisopropanolamine

[0227] C-4 N-Methyl-diethanolamine

[0228] C-5 N-methyl-2-aminoethan-1-ol

[0229] C-6 1-amino-propan-2-ol (propanol) DL

[0230] C-7 2-amino-propan-1-ol (racemate)

[0231] C-8 4-Amino-butan-1-ol

[0232] C-9 3-Amino-propan-1-ol

[0233] C-10 2-[2-(Dimethylamino)ethoxy]ethanol

[0234] C-11 3-Amino-1,2-propanediol

[0235] C-12 2-(2-aminoethoxy)ethanol (diglycolamine)

[0236] Other N-containing substances

[0237] C-13 Ammonia (Comparative)

[0238] C-14 2-(2-aminoethylamino)ethanol (comparative)

[0239] C-15 3-amino-octan-4-ol (H 9 C 4 -C(OH)-C(NH 2 )-C 2 H 5 )(contrast)

[0240] Other additives:

[0241] D-1 Maleic Acid Acrylic Acid Copolymer

[0242] D-2 Citric Acid

[0243] D-3 DMSO

[0244] D-4 Ascorbic Acid

[0245] Example 1

[0246] Several corrosion inhibitor combinations were tested. An aqueous composition containing 10 wt% C-1, 0.63 wt% D-1, 0.50 wt% D-2, 15 wt% D-3, 3.50% D-4, and the inhibitors listed in Table 1, and the balance water was prepared. The concentrate was stirred at room temperature for another 30 min. The concentrate was diluted 50 times to obtain a ready-to-use PCC formulation.

[0247] Two cobalt blank wafer samples and two copper blank wafer samples (2×2 cm each) were pre-etched in 1 wt.% oxalic acid for 1 min each. The samples were rinsed with water and dried in air. The thickness of the cobalt and copper levels on the samples was determined by XRF. The ready-to-use PCC formulation was heated to 60°C and two cobalt blank wafer samples (2×2 cm) were immersed in the tempering solution for 3 min. The samples were then rinsed with ultrapure water and dried in air. The same procedure was repeated with two copper blank wafer samples. The thickness of the wafer samples was determined by XRF. The static etching rate (SER) was determined by calculating the difference in the thickness of the cobalt / copper levels before and after PCC solution treatment divided by the etching time of 3 min.

[0248] Table 1

[0249]

[0250] Table 1 shows that all combinations of cobalt and copper etch inhibitors exhibit low static etch rates for cobalt and copper.

[0251] Example 2

[0252] Several monoaminoalkanols C-1 to C-12 were tested. Compositions containing 1.00 wt% A-4, 0.50 wt% B-1, 0.63 wt% C-1, 0.50 wt% C-2, 15 wt% D-3, 3.50% D-4, and the monoaminoalkanols listed in Table 2, and the balance water were prepared. The compositions were diluted with water at 1:50 (wt) before use. Etching tests were performed with these compositions as described in Example 1. The results are shown in Table 2.

[0253] As a comparison, ammonia (C-13) and amines (C-14, C15) were tested under the same conditions. The results are shown in Table 2.

[0254] Table 2

[0255]

[0256] Table 2 shows that mono-amino-alkanols (number of C < 8) gave clear solutions, low SER and good post-etch surface quality.

[0257] Example 3

[0258] The synergistic effect of cobalt and copper corrosion inhibitors A and B was determined by measuring the SER of the two inhibitors on both metals Co and Cu. The results are shown in Tables 3 and 4, respectively. The relative residual Co and Cu etch rates were determined by dividing the etch rate with the inhibitor by the etch rate without any additive.

[0259] Table 3

[0260]

[0261] Inhibitors A1, A2, A3, A4 and A5 showed good inhibition properties for cobalt (Co).

[0262] Table 4

[0263]

[0264] The inhibitors B1, B2 and B3 according to the present invention showed good inhibition properties for copper (Cu). B4 also showed an inhibitory effect, but not as good as B1, B2 and B3.

[0265] The expected value (calculated value) is calculated by multiplying the respective residual SER [%] of each single component from Table 3 and Table 4 by the respective baseline value of the etching rate in the absence of an inhibitor (17 A / min for Co and 5 A / min for Cu). The results are shown in Table 5.

[0266] Table 5

[0267]

[0268] If one of the measured Co or Cu etch rates is lower than the expected (calculated) value, a synergistic effect exists. For the combination of A1 or A2 with B1, the experimental SER for cobalt is lower than expected. For the combination of A3 with B1, the experimental SER for copper is lower than expected. For the combination of A4 and A5 with B1, the experimental SER for cobalt and copper is lower than expected. For the combination of A5 with B2 and B3, the experimental SER for cobalt is lower than expected.

Claims

1. An alkaline composition for cleaning a substrate comprising a structure of copper or a copper alloy and a structure comprising cobalt or a cobalt alloy, the composition comprising: (a) 0.0001% to 0.2% by weight of a cobalt corrosion inhibitor selected from (i)C 10 To C 20 Alkyl sulfonic acid or C 12 To C 24 Alkylbenzenesulfonic acid, (ii) C8 to C 17 Alkylphosphonic acid or aminophosphonic acid having formula I1 in R I1 C8 to C 20 alkyl, R I2 Selected from H, C1 to C6 alkyl and -X I1 -P(O)(OH)2, and X I1 is selected from C1 to C6 alkanediyl, (iii)C 12 To C 18 Alkyl carboxylic acid, sarcosine of formula I2, or cocoyl sarcosine in R I1 It is C 12 To C 20 alkyl, R I3 Selected from H, C1 to C6 alkyl and -X I1 -C(O)-OH, and X I1 is selected from C1 to C6 alkanediyl, (iv) Phosphoric acid C 10 To C 20 Mono- or di-alkyl esters, These alkyl groups (i) to (iv) may be interrupted by one or more O or may contain one or more double bonds, (v) Salts of (i) to (iv); (b) 0.0001% to 0.5% by weight of a copper corrosion inhibitor selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; 5-methylbenzotriazole; tetrahydrobenzotriazole; and methyl-benzotriazol-1-yl)-methyl-imino-bisethanol; (c) 0.05% to 1% by weight of a C2 to C7 monoaminoalkanol; and (d) solvent; Wherein the solvent consists essentially of water.

2. The composition according to claim 1, wherein The cobalt inhibitor is selected from the group consisting of dodecylbenzylsulfonic acid, cocoylsarcosine, oleoylsarcosine, cocoylphosphonic acid derivatives and C6-C 10 Alkyl phosphates.

3. The composition according to claim 1 or 2, wherein The copper inhibitor is selected from the group consisting of benzotriazole, 5-chlorobenzotriazole, 4-methylbenzotriazole; 5-methylbenzotriazole; tetrahydrobenzotriazole; and methyl-benzotriazol-1-yl)-methyl-imino-bisethanol.

4. A composition according to any one of the preceding claims, wherein The monoaminoalkanol is selected from 2-amino-ethane-1-ol, 2-amino-propan-1-ol, 3-amino-propan-1-ol, 1-amino-propan-2-ol, 2-amino-1-methyl-propan-1-ol, 3-amino-1-methyl-propan-1-ol, 2-amino-2-methyl-propan-1-ol; 2-amino-butan-1-ol, 3-amino-butan-1-ol, 4-amino-butan-1-ol, 2-amino-3-methyl-butan-2 ... -1-ol, 4-amino-2-methyl-butan-1-ol, 3-amino-1-methyl-butan-1-ol, 2-amino-1-methylpropanol, 3,3'-iminobis(N,N-dimethylpropylamine), triethanolamine, diisopropanolamine, N-methyl-diethanolamine, 2-[2-(dimethylamino)ethoxy]ethanol, 3-amino-1,2-propanediol, and 2-(2-aminoethoxy)ethanol (diglycolamine).

5. The composition according to any one of the preceding claims, further comprising a dispersant selected from acrylic acid-maleic acid copolymers and polyvinylpyrrolidone, copolymers of styrene and acrylic acid, benzenesulfonic acid-formaldehyde condensates, naphthalenesulfonic acid formaldehyde condensates.

6. A composition according to any one of the preceding claims, further comprising a complexing agent selected from C2 to C6 hydroxycarboxylic acids, preferably in an amount of 0.005 to 0.5% by weight.

7. The composition according to claim 6, wherein The complexing agent is citric acid.

8. The composition according to any one of the preceding claims, further comprising a reducing agent selected from sugar alcohols, in particular sorbitol, preferably in an amount of 0.03 to 1.5% by weight.

9. The composition according to any one of the preceding claims, further comprising an oxygen scavenger selected from ascorbic acid, 4-methoxyphenol or gallic acid.

10. The composition according to any one of claims 1 to 9, further comprising a water-miscible aprotic or protic organic solvent in an amount of 0.1 to 1% by weight.

11. A composition according to any preceding claim having a pH of 9 to 11.

5.

12. A concentrate for preparing a composition according to any one of the preceding claims, the concentrate comprising: (a) 0.01% to 5% by weight of the cobalt corrosion inhibitor; (b) 0.01% to 1% by weight of the copper corrosion inhibitor; (c) 1 to 20% by weight of the monoaminoalkanol; (d) 0% to 20% by weight of one or more organic solvents; and (e) Residue of water.

13. Use of a composition according to any one of claims 1 to 11 for removing from a substrate (a) Post-etch residue (PERR) or post-ash residue (PARR), or (b) Chemical Mechanical Planarization (CMP) residues, The substrate includes (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface.

14. A method of processing a microelectronic device, the method comprising: (a) providing a microelectronic substrate comprising (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface, the microelectronic substrate having post-etching residue or post-ashing residue thereon; (b) providing a composition according to any one of claims 1 to 11; as well as (c) contacting (i) the cobalt or cobalt alloy surface and (ii) the copper or copper alloy surface with the composition for a time and at a temperature effective to at least partially, and preferably completely, remove the post-etch residues or post-ash residues from the substrate.

15. A method of processing a microelectronic device, the method comprising: (a) providing a microelectronic substrate comprising (i) a cobalt or cobalt alloy surface and (ii) a copper or copper alloy surface, the microelectronic substrate having a chemical mechanical planarization (CMP) residue thereon; (b) providing a composition according to any one of claims 1 to 11; as well as (c) contacting (i) the cobalt or cobalt alloy surface and (ii) the copper or copper alloy surface with the composition for a time and at a temperature effective to at least partially, and preferably completely, remove the chemical mechanical planarization (CMP) residues from the liner.

16. A method for manufacturing a semiconductor device, the method comprising processing according to any one of claims 14 or 15.

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