Slurry composition for chemical mechanical polishing and method of manufacturing semiconductor device

Abstract

A slurry composition for chemical mechanical polishing (CMP) is provided that includes an organic abrasive material that includes a supramolecular compound (e.g., a supramolecular assembly), a homoform thereof, or a derivative thereof. The slurry composition for chemical mechanical polishing can reduce or prevent defects caused by CMP, thereby reducing or suppressing product defects with higher polishing selectivity.

Description

Technical Field

[0001] The present disclosure relates to a slurry composition for chemical mechanical polishing including a supramolecular compound (e.g., a supramolecular assembly) as an organic abrasive material, or a homologue or a derivative thereof, and a method for manufacturing a semiconductor device including, for example, chemical mechanical polishing by contacting a surface of a semiconductor substrate (also referred to as a substrate) or a surface of a layer formed on the substrate with a polishing pad using the slurry composition. Background Art

[0002] Recently, with the miniaturization of electronic devices and the resulting miniaturization of integrated circuits, various methods of forming microstructures such as metal wirings or shallow trench isolations having a width of several nanometers are being studied.

[0003] In the step of forming the microstructure, a polishing process may be performed to form a plane and / or flat surface of the microstructure. The polishing process may include, for example, chemical mechanical polishing (CMP). Chemical mechanical polishing is performed by providing a polishing slurry including an abrasive between a semiconductor substrate and a polishing pad, and then contacting the semiconductor substrate or a layer formed on the substrate with the polishing pad to flatten the surface of the substrate or the surface of the layer formed on the substrate. When an abrasive material such as inorganic polishing particles is added to the slurry composition for chemical mechanical polishing, the abrasive material may cause product defects depending on the polishing conditions. Summary of the invention

[0004] An aspect of the present disclosure is to provide a slurry composition for chemical mechanical polishing that can reduce or completely prevent scratches, can exhibit a higher metal removal rate than an insulating layer such as silicon dioxide, and / or can be easily post-cleaned after the polishing process.

[0005] A slurry composition for chemical mechanical polishing (CMP) according to some embodiments of the present invention may include an organic abrasive material, wherein the organic abrasive material includes a supramolecular compound (eg, supramolecular assembly), an analog thereof, or a derivative thereof.

[0006] The supramolecular compound may have a structure in which several building blocks are self-assembled to form the structure, and the building block may have a chemical structure of a macrocyclic molecule or polyethylene glycol.

[0007] The structural unit having a chemical structure of a macrocyclic molecule may include cucurbituril, calixarene, pillararene, crown ether or porphyrin.

[0008] The structural unit having the chemical structure of polyethylene glycol may further include a hydrophobic group.

[0009] The structural unit having the chemical structure of polyethylene glycol may include or may consist of an ethylene glycol group and a hydrophobic group, or a molecular weight ratio of the ethylene glycol group to the hydrophobic group may be about 1:2 to about 1:8.

[0010] The hydrophobic group may include an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a combination thereof.

[0011] The structural unit having the chemical structure of polyethylene glycol may be represented by Chemical Formula 1.

[0012] [Chemical formula 1]

[0013]

[0014] In Chemical Formula 1,

[0015] R 1 is a substituted or unsubstituted C1 to C20 alkyl group, and

[0016] n is an integer from 1 to 100.

[0017] The structural units having the chemical structure of polyethylene glycol can form a micellar structure. In some embodiments, the supramolecular assembly comprises a micelle or is a micelle. In some embodiments, the structural units having the chemical structure of polyethylene glycol can self-assemble with each other to form a micellar structure.

[0018] The structural unit may include or consist of the macrocyclic molecule and a molecule of another structure that is non-covalently bonded to the macrocyclic molecule. In some embodiments, the molecule of another structure may have a different structure from the macrocyclic molecule.

[0019] The molecule of another structure non-covalently bonded to the macrocyclic molecule may be an amine molecule.

[0020] The supramolecular compound may have a particle size less than or equal to about 100 nm.

[0021] The content of the inorganic abrasive material in the slurry composition for CMP may be less than about 0.1 wt % based on the total amount of the slurry composition.

[0022] The slurry composition for CMP can be used for metal polishing.

[0023] The slurry composition for CMP may have a pH of about 2 to about 11.

[0024] The slurry composition for CMP may further include an oxidizing agent, a catalyst, an inhibitor, a chelating agent, a polishing accelerator, a stabilizer, a surfactant, or a combination thereof.

[0025] The slurry composition for chemical mechanical polishing (CMP) according to some embodiments of the present invention may include: an organic abrasive material in an amount of about 0.1 wt % to about 10 wt % based on the total amount of the slurry composition for CMP, wherein the organic abrasive material includes a supramolecular compound (e.g., supramolecular assembly), a homologue thereof, or a derivative thereof, and does not include an inorganic abrasive material. In some embodiments, no inorganic abrasive material is included in the slurry composition.

[0026] The slurry composition for CMP may have a pH of about 2 to about 5.

[0027] According to some embodiments of the present invention, a method for manufacturing a semiconductor device may include: arranging a semiconductor substrate and a polishing pad to face each other; supplying a slurry composition for CMP including a supramolecular compound (e.g., a supramolecular assembly), its isoforms, or its derivatives between the semiconductor substrate and the polishing pad; and bringing a surface of the semiconductor substrate or a surface of a layer formed on the semiconductor substrate into contact with the polishing pad to perform polishing.

[0028] The slurry composition for CMP may polish metal wiring on or in the semiconductor substrate.

[0029] The metal wiring may include tungsten.

[0030] The slurry composition for CMP according to some embodiments of the present invention can improve polishing performance while reducing damage and shape deformation of fine pitch structures. Specifically, the slurry composition for CMP according to one aspect includes a supramolecular compound as an organic abrasive material, in which structural units (e.g., two or more identical compounds or molecules, or two or more different compounds or molecules) are connected (self-assembled) by non-covalent bonds through a simple mixing process, which can make it possible for scratches not to initially appear according to the particle size, elasticity can be adjusted according to the type and length of the structural unit, excellent polishing performance can be exhibited on various films, and / or because the supramolecular compound can be produced by mixing the structural units, the synthesis cost of the organic abrasive material can be low. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a view showing that several macrocyclic molecules self-assemble into building blocks to form a supramolecular compound.

[0032] Figure 2 is a view showing that compounds having the chemical structure of several polyethylene glycols self-assemble into building blocks to form supramolecular compounds.

[0033] Figure 3is a view showing that a supramolecular compound having a structure in which several structural units are self-assembled can be scratch-free or completely scratch-free when used as an organic abrasive material.

[0034] Figure 4 is a perspective view showing a polishing apparatus capable of performing chemical mechanical polishing.

[0035] Figures 5 to 7 is a cross-sectional view illustrating a method of manufacturing a semiconductor device according to some embodiments of the present invention.

[0036] Figure 8 is a cross-sectional photograph of tungsten taken after polishing tungsten with the slurry composition for CMP according to Example 4.

[0037] Fig. 9 is a cross-sectional photograph of tungsten taken after polishing tungsten with the slurry composition for CMP according to Comparative Example 1. DETAILED DESCRIPTION

[0038] The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which some example embodiments of the invention are shown. As those skilled in the art will realize, the described embodiments may be modified in various different ways, all without departing from the scope of the present invention.

[0039] The drawings and description are to be regarded as illustrative in nature, rather than restrictive.Throughout the specification, like reference numerals designate like elements.

[0040] For better understanding and ease of description, the size and thickness of each constituent element shown in the drawings are randomly indicated, and the present disclosure is not necessarily limited to what is shown. In the drawings, the thickness of layers, films, panels, regions, etc. are exaggerated for clarity. In addition, in the drawings, the thickness of some layers and regions is exaggerated for better understanding and ease of description.

[0041] It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element, or there can be intervening elements. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements. The terms "on" or "above" mean disposed on or below an object portion, and do not necessarily mean disposed on the upper side of an object portion based on the direction of gravity.

[0042] In addition, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.

[0043] In addition, throughout the specification, when “plane” is mentioned, this means when the target portion is viewed from above, and when “cross section” is mentioned, this means when the cross section of the target portion is cut vertically from the side.

[0044] As used herein, when no definition is otherwise provided, "substituted" refers to replacement of hydrogen with a substituent selected from a halogen atom (F, Cl, Br or I), a hydroxyl group, a C1 to C20 alkoxy group, a nitro group, a cyano group, an amine group, an imino group, an azido group, an amidino group, a hydrazine group, a hydrazone group, a carbonyl group, a carbamoyl group, a thiol group, an ester group, an ether group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid or a salt thereof, a C1 to C20 alkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C3 to C20 cycloalkyl group, a C3 to C20 cycloalkenyl group, a C3 to C20 cycloalkynyl group, a C2 to C20 heterocycloalkyl group, a C2 to C20 heterocycloalkenyl group, a C2 to C20 heterocycloalkynyl group, a C3 to C20 heteroaryl group, or a combination thereof.

[0045] Figure 4 is a perspective view showing a polishing apparatus 100 capable of performing chemical mechanical polishing.

[0046] refer to Figure 4 , the polishing apparatus 100 includes a rotating disc-shaped platen 120 on which a polishing pad 110 is disposed. The platen 120 is operable to rotate about an axis 125. For example, a motor 121 can rotate a drive shaft 124 to rotate the platen 120. The polishing pad 110 can be a polishing pad 110 having two or more layers, the two or more layers including an outer polishing layer 112 and a softer backing layer 114.

[0047] The polishing apparatus 100 may include a slurry port 130 on the polishing pad 110 for dispensing an abrasive material 132 such as slurry toward the polishing pad 110. The polishing apparatus 100 may also include a polishing pad dresser 160 for grinding the polishing pad 110 to maintain the polishing pad 110 in a consistent polishing state.

[0048] The polishing apparatus 100 includes at least one carrier head 140. The carrier head 140 can operate to hold the substrate 10 against the polishing pad 110. The carrier head 140 can control polishing parameters, such as pressure, associated with each individual substrate.

[0049] Specifically, the carrier head 140 may include a retaining ring 142 to hold the substrate 10 below the flexible membrane. The carrier head 140 may also include a plurality of independently controllable pressurizable chambers defined by the flexible membrane that can apply independently controllable pressure to the flexible membrane and thus to relevant areas on the substrate 10.

[0050] The carrier head 140 is suspended on a support structure 150 (e.g., a turntable or track) and is connected to a carrier head rotation motor 154 by a drive shaft 152 so that the carrier head is rotatable about an axis 155. Optionally, the carrier head 140 can be vibrated laterally, for example, on a slide rail on the support structure (e.g., turntable) 150 or track or by rotational vibration of the turntable itself. In operation, the platen 120 rotates about its central axis 125, the carrier head 140 rotates about its central axis 155, and they translate laterally across the uppermost surface of the polishing pad.

[0051] Despite Figure 4 Only one carrier head 140 is shown in FIG. 1 , but two or more carrier heads may be provided to hold additional substrates so that the surface area of ​​the polishing pad 110 may be efficiently utilized.

[0052] The polishing apparatus 100 also includes a control system for controlling the rotation of the platen 120. The control system may include a controller 190 such as a general purpose programmable digital computer, an output device 192 for output (eg, a monitor), and an input device 194 for input (eg, a keyboard).

[0053] exist Figure 4 In FIG. 1 , the control system is shown as being connected only to the motor 121, but may also be connected to the carrier head 140 to adjust the head pressure or rotation speed of the carrier head. In addition, the control system may be connected to the slurry port 130 to adjust the supply of slurry.

[0054] Some embodiments of the present invention provide slurry compositions for chemical mechanical polishing (CMP) that may be used in the polishing apparatus 100 .

[0055] Slurry compositions for CMP include organic abrasive materials.

[0056] According to some embodiments of the present invention, a slurry composition for CMP using an organic abrasive material as an abrasive material can solve problems (CMP-induced defects) caused by particle refinement of conventional widely used inorganic abrasive materials.

[0057] As devices become more complex in structure due to high density, three-dimensional structure, etc., and line width is miniaturized to a range of about 10nm or less, CMP technology, one of the key processes for manufacturing semiconductors, becomes more important and more necessary. Therefore, as the difficulty and requirements of the CMP process become higher, the problem of defects caused by CMP, which has a key impact on the yield of semiconductor manufacturing, is rising.

[0058] In the CMP process, micron and nano scratch defects are considered to be a long-standing problem and are seen as damage caused by inorganic abrasive material particles. In addition, another problem such as dishing and erosion caused by local over-polishing in fine pattern areas has also been reported to be closely related to inorganic abrasive materials.

[0059] As the minimum feature size of wiring (e.g., semiconductor wiring or metal wiring) decreases and the number of stacked layers increases, problems such as scratch defects, dents, and erosion have a fatal impact on semiconductor mass production yield. Accordingly, in order to suppress these CMP defects, an abrasive with a nanometer size smaller than the designed wiring line width is desired.

[0060] However, because new physical / chemical (nanosize effect) phenomena different from classical mechanics come into play as governing rules, inorganic materials (silicon dioxide, cerium oxide, aluminum oxide, zirconium oxide, etc.) used as conventional abrasive materials, when their particles are refined to a size of several nanometers, not only does it make it difficult (sometimes impossible) to control defects caused by CMP, but it also sharply increases the management cost and defect inspection cost for suppressing defect generation and deteriorates the polishing performance, thereby inevitably causing arduous difficulties in semiconductor yield management.

[0061] Therefore, the present inventors provide a novel organic abrasive material, specifically, "a nano-sized organic abrasive material having a specific molecular structure", and more specifically, an organic supramolecular compound (or its isotype or derivative). Due to the characteristics of organic molecules that originally have no nano-size effect, for organic abrasive materials, there may be no distinction between atoms inside the particle and atoms on its surface.

[0062] The organic abrasive material according to some embodiments is stable under strong acid and strong base conditions, has very stable bonds in structure, and therefore exhibits very excellent chemical and mechanical stability, and since the agglomerates are really formed by random stacking, they may exhibit no increase in hardness. In addition, the organic abrasive material has chemical interactions in a specific orientation, which in principle does not produce scratch defects, resulting in significant reductions in depressions and erosion. In particular, compared to polymer-based organic abrasive materials conventionally used as organic abrasive materials, the organic abrasive material according to some embodiments can have a constant size and shape, and can therefore be used as an excellent abrasive material. In some embodiments, the organic abrasive material according to some embodiments can have a uniform size and shape. Figure 3 This is a view showing that a supramolecular compound having a structure in which several structural units are self-assembled can be scratch-free or completely scratch-free when used as an organic abrasive. Figure 3As shown in , since the organic abrasive material according to some embodiments has a chemical action only in the direction of the uneven surface of the material to be polished, the uneven structure can be removed by chemical bonding to easily flatten the substrate, just like removing dust (unevenness) on the surface of the substrate by using a tape.

[0063] Organic abrasive materials

[0064] Organic abrasive materials include supramolecular compounds (e.g., supramolecular assemblies), isoforms thereof, or derivatives thereof. Supramolecular compounds are non-polymers and have, for example, a self-assembled structure of several structural units, and the structural unit may have a chemical structure of a macrocyclic molecule or polyethylene glycol. In certain embodiments, supramolecular compounds have a self-assembled structure formed by two or more structural units and / or provided by two or more structural units, wherein the two or more structural units may be identical or different. In certain embodiments, supramolecular compounds have a self-assembled structure formed by two or more structural units with a chemical structure of a macrocyclic molecule or polyethylene glycol and / or provided. Supramolecular compounds may be formed and / or provided (e.g., self-assembled) by including two or more structural units together (e.g., included in the same composition). In certain embodiments, supramolecular compounds are self-assembled structures of two or more identical compounds. In certain embodiments, supramolecular compounds are self-assembled structures of two or more different compounds.

[0065] (Macrocyclic Molecular Compounds)

[0066] The structural unit with the chemical structure of macrocyclic molecule can include, for example, cucurbituril, calixarene, pillararenes, crown ether, cyclodextrin or porphyrin, but the present invention is not limited thereto. Non-limiting examples of cucurbituril and its homologues or derivatives include, but are not limited to, those described in the following articles: Kim, J. et al., J. Am. Chem. Soc. 2000, 122, 540–541; Day, A. et al., J. Org. Chem. 2001, 66, 8094–8100; Lee, JW et al., Cucurbituril Homologues and Derivatives: New Opportunities in Supramolecular Chemistry.Acc.Chem.Res.2003,36,621–630; and Isaacs, L.; Park, S.-K.; Liu, S.; Ko, YH; Selvapalam, N.; Kim, Y.; Kim, H.; Zavalij, PY; Kim, G.-H.; Lee, H.-S.; Kim, KJ Am. Chem. Soc. 2005, 127, 18000–18001. Non-limiting examples of cyclodextrins and their isoforms or derivatives include, but are not limited to, those described in the following articles: Del Valle, EMM Cyclodextrins and Their Uses: A Review. Process. Biochem. 2004, 39, 1033–1046; Crini, G. Review: A History of Cyclodextrins. Chem. Rev. 2014, 114, 10940–10975; and Morin-Crini, N.; Fourmentin, S.; Fenyvesi, Lichtfouse, E.; Torri, G.; Fourmentin, M.; Crini, G. 130 Years of Cyclodextrin Discovery for Health, Food, Agriculture, and the Industry: A Review. Environ. Chem. Lett. 2021, 19, 2581–2617. Non-limiting examples of pillar arenes and their homologues or derivatives include, but are not limited to, those described in the following articles: Ogoshi, T. et al., Pillar-Shaped Macrocyclic Hosts Pillar[n]arenes: New Key Playersfor Supramolecular Chemistry. Chem. Rev. 2016, 116, 7937–8002; Guo, F. et al., Recent progress in the research on the host-guest chemistry of pillar[n]arenes. Supramol. Chem. 2018, 30, 81–92; and Ogoshi, T.; Kakuta, T.; Yamagishi, T.-a. Applications of Pillar[n]arene-Based Supramolecular Assemblies. Angew. Chem. Int. Ed. 2019, 58, 2197–2206.

[0067] Figure 1 This is a view showing that several macrocyclic molecules self-assemble into building blocks to form supramolecular compounds. Figure 1 , when the compound with the chemical structure of macrocyclic molecule such as cucurbituril is mixed, a single aggregate can be formed by self-assembly. Since the macrocyclic compound itself forms a macrocyclic molecule, it can also include molecules with other structures that are non-covalently bonded to the macrocyclic molecule. In certain embodiments, the molecule with other structures can have a structure different from the macrocyclic molecule. That is, it can be a core-shell compound in which the non-covalently bonded molecule of another structure is used as a core and the macrocyclic molecule around it is used as a shell. These core-shell compounds can also serve as structural units to form a supramolecular compound that self-assembles with each other.

[0068] The molecule of other structure that can be non-covalently bonded to the macrocyclic molecule that can serve as the core can be, for example, an amine molecule (e.g., having a terminal end such as *-NH 2 and *-NH 3 +), but the present invention is not necessarily limited thereto.

[0069] (Compound having the chemical structure of polyethylene glycol)

[0070] The structural unit with the chemical structure of polyethylene glycol can also include a hydrophobic group. The chemical structure of polyethylene glycol itself can have a hydrophilic group and a hydrophobic group. That is, in some embodiments, the structural unit with the chemical structure of polyethylene glycol can include both a hydrophilic group (e.g., an ethylene glycol group) and a hydrophobic group.

[0071] In some embodiments, the structural unit having the chemical structure of polyethylene glycol may include an ethylene glycol group and a hydrophobic group, and the molecular weight ratio of the ethylene glycol group to the hydrophobic group may be about 1:2 to about 1:8. For example, the structural unit having the chemical structure of polyethylene glycol may be composed of (e.g., consist of) an ethylene glycol group and a hydrophobic group, and the molecular weight ratio of the ethylene glycol group to the hydrophobic group may be about 1:2 to about 1:8.

[0072] For example, the hydrophobic group may include an alkyl group, an alkenyl group, an alkynyl group, an aryl group, or a combination thereof.

[0073] When the molecular weight ratio of the hydrophilic ethylene glycol group to the hydrophobic alkyl, alkenyl, alkynyl and / or aryl group is controlled within the above range, the selectivity of tungsten to oxide can be greatly increased compared to the existing slurry composition for CMP.

[0074] For example, a structural unit having the chemical structure of polyethylene glycol can be represented by Chemical Formula 1.

[0075] [Chemical formula 1]

[0076]

[0077] In Chemical Formula 1,

[0078] R 1 is a substituted or unsubstituted C1 to C20 alkyl group, and

[0079] n is an integer from 1 to 100.

[0080] The macrocyclic molecular compound can form a core-shell structure through a non-covalent bond with a molecule (eg, an amine molecule, etc.). Figure 2 This is a view showing that compounds with the chemical structure of several polyethylene glycols self-assemble into building blocks to form supramolecular compounds. Figure 2 , compounds having the chemical structure of polyethylene glycol can also act as structural units and self-assemble with each other to form a micellar structure similar to the core-shell structure.

[0081] For example, based on the total amount of the slurry composition for CMP according to some embodiments, an amount of about 0.1 wt % to about 25 wt %, such as about 0.1 wt % to about 20 wt %, such as about 0.1 wt % to about 15 wt %, or such as about 0.1 wt % to about 10 wt % of organic abrasive material may be included. In this article, the polishing performance can be further improved while increasing the selectivity of the metal to the oxide. Specifically, when the organic abrasive material is included in an amount less than about 0.1 wt % based on the total amount of the composition, the content is so small that there is an insufficient polishing effect, but when the organic abrasive material is included in an amount greater than about 25 wt % based on the total amount of the composition, the polishing rate may be difficult to control.

[0082] For example, the supramolecular compound can have a particle size of less than or equal to about 100 nm, such as less than or equal to about 90 nm, such as less than or equal to about 80 nm, such as less than or equal to about 70 nm, such as less than or equal to about 60 nm, such as less than or equal to about 50 nm, such as less than or equal to about 40 nm, such as less than or equal to about 30 nm, such as less than or equal to about 20 nm, or such as less than or equal to about 10 nm. Considering that the particle size of inorganic abrasive materials is usually less than or equal to about 500 nm, the supramolecular compound has a very small particle size and can be effectively applied to structures with fine pitches. For example, because the longest diameter of cucurbituril is less than or equal to about 2 nm, it is expected that the particle size of the supramolecular compound using cucurbituril as a structural unit is very small.

[0083] The slurry composition for CMP according to some embodiments may include a very small amount of inorganic abrasive material, wherein the content of the inorganic abrasive material may be less than about 0.1 wt %, such as less than about 0.08 wt %, such as less than about 0.05 wt %, such as less than about 0.03 wt %, such as less than about 0.01 wt %, such as less than about 0.008 wt %, such as less than about 0.005 wt %, such as less than about 0.003 wt %, such as less than about 0.001 wt %, such as less than about 0.0008 wt %, such as less than about 0.0005 wt %, such as less than about 0.0003 wt %, or such as less than about 0.0001 wt %, based on the total amount of the slurry composition for CMP. The slurry composition for CMP according to some embodiments may include a very small amount of inorganic abrasive material, and has a very excellent effect of reducing various defects (e.g., particle defects, scratches, etc.) due to the inorganic abrasive material, and has excellent selectivity of metal (particularly tungsten) to oxide compared with conventional slurry compositions for CMP. Furthermore, various process / management problems caused by inorganic particles (e.g., quality deterioration due to aggregation of inorganic abrasive material particles, slurry filter replacement costs, wastewater pipe clogging, complexity of wastewater treatment processes, etc.) are almost unlikely to occur.

[0084] The inorganic abrasive material may be any inorganic particles widely used in slurry compositions for CMP, such as metal oxides, but is not limited thereto.

[0085] In some embodiments, the slurry composition for CMP may not include or may not contain inorganic abrasive materials. For example, the slurry composition for CMP may not include or may not contain metal oxide particles. For example, the slurry composition for CMP may not include silicon dioxide, aluminum oxide, cerium oxide, titanium oxide, zirconium oxide, magnesium oxide, germanium oxide (e.g., GeO 2 ) and manganese oxides (e.g., Mn 2 O 3 )

[0086] Here, "not including" particles means that particles are not added intentionally, but does not mean that particles do not exist at all or exist below the detection limit. Therefore, the slurry composition for CMP may include these particles in a certain amount of inevitable impurities.

[0087] The inorganic abrasive material conventionally included in the slurry composition for CMP may damage the semiconductor device formed on the polishing target according to the polishing conditions. In other words, the inorganic abrasive material may damage the layer, wiring, pattern, etc. formed on the polishing target, or may not be sufficiently removed but remain after polishing, thereby causing contamination.

[0088] In addition, the inorganic abrasive material shortens the polishing pad 110 used for polishing (refer to Figure 4 )’s life, resulting in replacement costs for the polishing pad 110 and opportunity costs due to downtime for replacing the polishing pad 110.

[0089] However, when an organic abrasive material is appropriately selected according to some embodiments, sufficient polishing rate and high selectivity can be obtained without an inorganic abrasive material. When an inorganic abrasive material is not included in the slurry composition for CMP, damage and contamination to the polishing target will not be caused, and the polishing pad can be less worn, thereby reducing manufacturing costs. In addition, because the slurry composition for CMP itself becomes cheaper, the manufacturing cost can be further reduced.

[0090] The slurry composition for CMP according to some embodiments may also not include a dispersion stabilizer. As described above, since the slurry composition for CMP according to some embodiments does not include an inorganic abrasive material, it may not be necessary to generally add a dispersion stabilizer to ensure good dispersion of the inorganic abrasive material.

[0091] For example, the slurry composition for CMP does not include one of ethylene oxide, ethylene glycol, ethylene glycol distearate, ethylene glycol monostearate, ethylene glycol polymer, ethylene glycol ether, alkylamine-containing alcohol, polymer ether-containing compound, vinyl pyrrolidone, cellulose and ethoxylate as a dispersion stabilizer. Specifically, the slurry composition for CMP may not include diethylene glycol hexadecyl ether, decaethylene glycol hexadecyl ether, diethylene glycol octadecyl ether, diethylene glycol octadecyl ether, eicosyl glycol octadecyl ether, diethylene glycol oleyl ether, decaethylene glycol oleyl ether, decaethylene glycol octadecyl ether, nonylphenol polyethylene glycol ether, ethylenediaminetetraacetic acid (ethoxy block-propoxylate) tetraol, ethylenediaminetetraacetic acid (propoxy block-ethoxylate) tetraol, polyethylene block poly (ethylene glycol), polyoxyethylene isooctylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene tridecyl ether, polyoxyethylene sorbitol tetraoleate ... Any one of alcohol hexaoleate, polyethylene glycol sorbitan monolaurate, polyoxyethylene sorbitan monolaurate, sorbitan monopalmitate, FS-300 nonionic fluorosurfactant, FSN nonionic fluorosurfactant, FSO nonionic ethoxylated fluorosurfactant, vinyl pyrrolidone, 2,4,7,9-tetramethyl-5-decyne-4,7-diol ethoxylate, 8-methyl-1-nonanol propoxylate block-ethoxylate, allyl alcohol 1,2-butoxylate block-ethoxylate, polyoxyethylene branched nonyl cyclohexyl ether and polyoxyethylene isooctyl cyclohexyl ether is used as a dispersion stabilizer.

[0092] pH Adjusters

[0093] For example, the pH of the slurry composition for CMP can be achieved or maintained by any suitable means, taking into account any polishing rate, dispersion stability, etc. For example, the pH of the slurry composition for CMP can be, for example, about 2 to about 11, and within the above range, can be about 2 to about 8, about 2 to about 7, about 2 to about 6, or about 2 to about 5. When the pH of the slurry composition for CMP is controlled within the above range, the polishing performance of metals, especially tungsten, can be optimized. More specifically, when the pH of the slurry composition for CMP is controlled to about 2 to about 5, the polishing performance of metals such as tungsten can be improved, and when the pH of the slurry composition for CMP is controlled to about 6 to about 11, the polishing performance for non-metallic dielectrics can be improved.

[0094] As required, acid solutions and alkaline solutions can be appropriately used to control the pH of the slurry composition for CMP. In some embodiments, the pH adjusting agent may include an acid solution such as sulfuric acid, phosphoric acid, hydrochloric acid, nitric acid, carboxylic acid, maleic acid, malonic acid, citric acid, oxalic acid, tartaric acid and / or an alkaline solution such as calcium hydroxide, potassium hydroxide, ammonium hydroxide, sodium hydroxide, magnesium hydroxide, triethylamine, tetramethylammonium hydroxide and ammonia, but is not limited thereto. The pH adjusting agent in an amount such that the pH of the slurry composition for CMP has a predetermined range (e.g., a desired range) can be included in the slurry composition for CMP, and the pH adjusting agent is not particularly limited.

[0095] For example, the slurry composition for CMP may further include a carrier, an oxidizing agent, a catalyst, an inhibitor, a chelating agent, a polishing accelerator, a stabilizer, a surfactant, or a combination thereof.

[0096] Carrier (Solvent)

[0097] The carrier may be any liquid capable of substantially uniformly dispersing the organic abrasive material or the organic polishing accelerator, and is not particularly limited. The carrier may be an aqueous solvent or an organic solvent.

[0098] In some embodiments, the carrier may include, for example, water, deionized water, ultrapure water, alcohols (e.g., propanol, isopropanol, ethanol, 1-propanol, methanol, 1-hexanol, etc.), aldehydes (e.g., formaldehyde, acetaldehyde, etc.), esters (e.g., ethyl formate, propyl formate, ethyl acetate, methyl acetate, methyl lactate, butyl lactate, ethyl lactate, etc.), ketones (e.g., acetone, diacetone alcohol, methyl ethyl ketone, etc.), dimethyl sulfoxide (DMSO), tetrahydrofuran, dioxane, diethylene glycol, amides (e.g., N,N-dimethylformamide, dimethylimidazolidinone, N-methylpyrrolidone, etc.), polyols and their derivatives (e.g., ethylene glycol, glycerol, diethylene glycol, diethylene glycol monomethyl ether, etc.), nitrogen-containing organic compounds (e.g., acetonitrile, pentylamine, isopropylamine, imidazole, dimethylamine, etc.) or mixtures thereof.

[0099] In addition to the above-mentioned organic abrasive material, pH adjuster and other components described later, the content of the carrier may be a balance amount.

[0100] Surfactants

[0101] The slurry composition for CMP may further include a surfactant as required. The surfactant may be appropriately selected from nonionic surfactants, cationic surfactants, anionic surfactants and amphoteric surfactants.

[0102] Examples of nonionic surfactants may include: polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether or polyoxyethylene stearyl ether; polyoxyethylene alkylphenyl ethers such as polyoxyethylene octylphenyl ether or polyoxyethylene nonylphenyl ether; sorbitol higher fatty acid esters such as sorbitan monolaurate, sorbitan monostearate or sorbitan trioleate; polyoxyethylene sorbitan ester higher fatty acid esters such as polyoxyethylene sorbitan monolaurate; polyoxyethylene higher fatty acid esters such as polyoxyethylene monolaurate or polyoxyethylene monostearate; for example, glycerol higher fatty acid esters such as oleic acid monoglyceride, stearic acid monoglyceride, etc.; polyoxyalkylenes such as polyoxyethylene, polyoxypropylene or polyoxybutylene; and block copolymers thereof.

[0103] Examples of the cationic surfactant may include alkyltrimethylammonium chloride, dialkyldimethylammonium chloride, benzalkonium chloride salts, and alkyldimethylammonium ethanol sulfate.

[0104] Examples of anionic surfactants may include: carboxylates such as sodium laurate, sodium oleate, N-acyl-N-methylglycine sodium salt, polyoxyethylene lauryl ether carboxylate sodium salt; sulfonates such as sodium dodecylbenzenesulfonate, dialkyl sulfosuccinate salts, 5-sulfoisophthalic acid dimethyl ester sodium salt; sulfate esters such as sodium lauryl sulfate, polyoxyethylene lauryl ether sodium sulfate or polyoxyethylene nonylphenyl ether sodium sulfate; phosphate esters such as polyoxyethylene lauryl sodium phosphate or polyoxyethylene nonylphenyl sodium phosphate; and the like.

[0105] Examples of the amphoteric surfactant may include carboxybetaine-type surfactants, aminocarboxylates, imidazoline betaine, lecithin, and alkylamine oxides.

[0106] The surfactant may be included in the slurry composition for CMP in an amount of about 0.001 wt % to about 0.5 wt %.

[0107] Planarizing agent

[0108] If necessary, the slurry composition for CMP may further include a planarizing agent (also called a leveling agent) to reduce the unevenness of the surface to be polished.

[0109] Non-limiting examples of the leveling agent may include ammonium chloride, ammonium lauryl sulfate, polyethylene glycol, polyoxyethylene alkyl ether sulfate triethanolamine, polyvinyl pyrrolidone, polyacrylaldehyde, and the like.

[0110] The planarizing agent may be included in the slurry composition for CMP in an amount of about 0.1 wt % to about 1 wt %.

[0111] Oxidants

[0112] The slurry composition for CMP may also include an oxidant. The oxidant oxidizes the surface of the film (e.g., metal film) to change the film (e.g., metal film) to an easily oxidizable state. Non-limiting examples of the oxidant may include: organic peroxides such as hydrogen peroxide, peracetic acid, perbenzoic acid, or tert-butyl hydroperoxide; permanganate compounds such as potassium permanganate; dichromic acid compounds such as potassium dichromate; halogen acid compounds such as potassium iodate; nitric acid compounds such as nitric acid and ferric nitrate; perhalogen acid compounds such as perchloric acid; persulfates such as sodium persulfate, potassium persulfate, or ammonium persulfate; percarbonates such as sodium percarbonate or potassium percarbonate; urea peroxide; and heteropoly acids.

[0113] In addition, an auxiliary oxidant such as iron nitrate oxidize hydrate which can assist the oxidizing action of the oxidant may be used together with the oxidant.

[0114] Stabilizer

[0115] The slurry composition for CMP may also include a stabilizer, which can reduce or prevent rapid decomposition of the oxidizing agent and maintain its stability during polishing.

[0116] Corrosion Inhibitor

[0117] The slurry composition for CMP may further include a corrosion inhibitor for protecting the surface to be polished from corrosion as needed. When the corrosion inhibitor is further included, dishing, erosion, roughness, etc. may be improved.

[0118] Non-limiting examples of corrosion inhibitors may include triazole and its derivatives, benzotriazole and its derivatives. Triazole derivatives may include, but are not limited to, amino-substituted triazole compounds and bis-amino-substituted triazole compounds.

[0119] The corrosion inhibitor may be included in the slurry composition for CMP in an amount of about 0.001 wt % to about 0.15 wt %. In some embodiments, the amount of the corrosion inhibitor may be about 0.0025 wt % to about 0.1 wt % or about 0.005 wt % to about 0.05 wt %.

[0120] The slurry composition for CMP can be applied when forming various structures, and can be applied to, for example, a polishing process of a conductor such as a metal wiring or a polishing process of an insulator such as a shallow trench isolation (STI) or an insulating film. For example, the slurry composition for CMP can be used to polish a conductive layer, an insulating layer, and / or a semiconductor layer having a charged surface on or in a semiconductor substrate, and can be used, for example, to polish a conductive layer, an insulating layer, and / or a semiconductor layer having a generally negatively charged surface.

[0121] For example, the slurry composition for CMP may be used to polish a conductor such as a metal wiring on or in a semiconductor substrate, and may be used to polish a conductor such as copper (Cu), tungsten (W), or an alloy thereof.

[0122] Hereinafter, an example of a method of manufacturing a semiconductor device using the aforementioned slurry composition for CMP will be described.

[0123] Figures 5 to 7 is a cross-sectional view illustrating a method of manufacturing a semiconductor device according to some embodiments of the present invention.

[0124] refer to Figure 5, an interlayer insulating layer 20 is formed on the semiconductor substrate 10. The interlayer insulating layer 20 may include, for example, oxide, nitride and / or oxynitride. Next, the interlayer insulating layer 20 is etched to form an opening (e.g., a groove) 20a. The groove 20a may have a width less than or equal to about 10nm. Subsequently, a barrier layer 30 is formed on the wall surface of the groove 20a. The barrier layer 30 may include, for example, Ti and / or TiN, but is not necessarily limited thereto.

[0125] refer to Figure 6 , a metal layer 40 is formed by filling the trench 20a with a metal such as tungsten (W).

[0126] refer to Figure 7 , a buried metal layer 40a is formed by flattening the surface of the metal layer 40 to match the surface of the interlayer insulating layer 20. The flattening can be performed by chemical mechanical polishing using a chemical mechanical polishing (CMP) device, and the aforementioned slurry composition for CMP can be used. This will be described later. For example, when the barrier layer 30 is a TiN layer and the metal layer 40 is a W layer, the polishing selectivity of TiN to W of the slurry composition for CMP is as high as possible, and for example, higher than about 50:1, the better.

[0127] The planarization for forming the buried metal layer 40a will be described below. The planarization may be performed by chemical mechanical polishing using a chemical mechanical polishing (CMP) apparatus as described above.

[0128] For example, the chemical mechanical polishing apparatus described above may include: a lower base; a platen rotatably disposed on an upper surface of the lower base; a polishing pad disposed on the platen; a pad conditioner; and at least one CMP slurry composition supply device disposed adjacent to the polishing pad to supply (e.g., apply) the CMP slurry composition to the polishing pad (see Figure 4 ).

[0129] The pressing plate may be rotatably arranged on the surface of the lower base. For example, the pressing plate may receive rotational power from a motor arranged in the lower base. Therefore, the pressing plate may rotate based on an imaginary rotation axis perpendicular to the surface of the pressing plate. The imaginary rotation axis may be perpendicular to the surface of the lower base.

[0130] The platen may have one or more supply lines through which liquid may be injected and discharged. Water may be injected and discharged into the platen through the supply lines, and the temperature of the platen may be controlled by the injected water. For example, cooling water may be injected and discharged into the platen through the supply lines, thereby reducing the temperature of an overheated platen. For example, hot water may be injected and discharged into the platen through the supply lines, thereby causing the temperature of the platen to increase.

[0131] The polishing pad may be positioned on the surface of the platen to be supported by the platen. The polishing pad may rotate together with the platen. The polishing pad may have a rough polishing surface. Such a polishing surface may directly contact the semiconductor substrate 10 or a layer formed on the semiconductor substrate 10 to mechanically polish the surface of the semiconductor substrate 10 or the surface of the layer formed on the semiconductor substrate 10. The polishing pad may be a porous material having a plurality of microspaces, and the plurality of microspaces may include a slurry composition for CMP.

[0132] The pad conditioner may be disposed adjacent to the polishing pad and maintain a state of the polishing surface such that a surface of the semiconductor substrate 10 or a surface of a layer formed on the semiconductor substrate 10 is effectively polished while the polishing process is performed.

[0133] The CMP slurry composition supply device can be arranged adjacent to the polishing pad, and can supply the slurry composition for CMP to the polishing pad. The CMP slurry composition supply device can include a nozzle capable of supplying the slurry composition for CMP to the polishing pad during the polishing process and a voltage supply unit capable of applying a predetermined voltage to the nozzle. The slurry composition for CMP in the nozzle can be loaded and discharged toward the polishing pad by the voltage applied from the voltage supply unit. The CMP slurry composition supply device can supply the aforementioned slurry composition for CMP.

[0134] In some embodiments, chemical mechanical polishing may be performed by the following steps: arranging the semiconductor substrate 10 and the polishing pad to face each other; supplying a slurry composition for CMP between the semiconductor substrate 10 and the polishing pad from a CMP slurry composition supply device; and bringing a surface of the semiconductor substrate 10 or a surface of a layer formed on the semiconductor substrate 10 into contact with the polishing pad to perform polishing.

[0135] For example, the slurry composition for CMP may be used to polish a conductor such as a metal wiring on or in a semiconductor substrate, and the slurry composition for CMP may be used to polish a conductor such as copper (Cu), tungsten (W) or an alloy thereof, but is not necessarily limited thereto.

[0136] For example, the slurry composition for CMP may be supplied at a rate of, for example, about 10 ml / min to about 100 ml / min.

[0137] Polishing is performed using mechanical friction by bringing the surface of the semiconductor substrate 10 or the surface of a layer formed on the semiconductor substrate 10 into contact with the polishing pad and rotating the polishing pad. For example, a pressure of about 1 psi to about 5 psi may be applied in the process of performing the polishing.

[0138] For example, when the metal layer 40 and the buried metal layer 40a include tungsten, the higher the ratio of the material removal rate (MRR) of tungsten relative to the etching rate (ER) of tungsten by the slurry composition for CMP, the better, and for example, the ratio can be greater than or equal to about 1, greater than or equal to about 2, greater than or equal to about 3, greater than or equal to about 4, greater than or equal to about 5, greater than or equal to about 6, greater than or equal to about 7, greater than or equal to about 8, greater than or equal to about 9, greater than or equal to about 10, greater than or equal to about 11, greater than or equal to about 12, greater than or equal to about 13, greater than or equal to about 14, greater than or equal to about 15, greater than or equal to about 16, greater than or equal to about 17, greater than or equal to about 18, greater than or equal to about 19, or greater than or equal to about 20, and within the above range, can be about 1 to about 20, about 2 to about 20, about 3 to about 20, about 3 to about 19, about 3 to about 18, or about 3 to about 17.

[0139] By having the ratio of the polishing rate to the etching rate as described above, it is possible to reduce the etching rate of the metal wiring, ensure the planarity of the semiconductor substrate after the polishing process, and solve problems such as dishing.

[0140] As described above, although the exemplary embodiments have been described, various additions, omissions, substitutions and changes may be made without being limited to the exemplary embodiments described above. In addition, other embodiments may be formed by combining elements in different embodiments.

[0141] Hereinafter, the configuration and effects of the present invention will be described in more detail with specific examples and comparative examples, but these examples are only intended to more clearly understand the present invention and are not intended to limit the scope of the present invention.

[0142] (Preparation of CMP Slurry Composition)

[0143] Comparative Example 1

[0144] A slurry was prepared including 1 wt% of silica (primary particle size 15 nm, PL-1, FUSO Chemical Co., Ltd.), 0.06 wt% of benzotriazole, 0.4 wt% of diammonium phosphate, 0.5 wt% of triammonium citrate, 1.6 wt% of hydrogen peroxide and a balance of water.

[0145] Example 1

[0146] 2.5 wt% cucurbituril, 2.4 wt% hydrogen peroxide, 0.32 wt% malonic acid and 0.0013 wt% ferric nitrate (FeNO 3 9H 2O) were mixed and then treated with a 5 M nitric acid solution to adjust the pH to 2.0. Cucurbituril was synthesized according to a known synthesis method (eg, J. Kim et al., J. Am. Chem. Soc., 2000, 122, 540).

[0147] Example 2

[0148] A slurry composition for CMP was prepared in the same manner as in Example 1, except that Triton X-102 (Dow) was used instead of cucurbituril.

[0149] Example 3

[0150] In addition to using 0.002 wt% instead of 0.0013 wt% of iron nitrate (FeNO 3 9H 2 A slurry composition for CMP was prepared in the same manner as in Example 2 except for the above.

[0151] Example 4

[0152] A slurry composition for CMP was prepared in the same manner as in Example 2, except that 0.06 wt % of benzotriazole was added.

[0153] (evaluate)

[0154] Pad: KPX IT-3000

[0155] CMP equipment: GnP Technology Poly 762

[0156] Objects to be polished: 12-inch tungsten non-patterned wafers, 12-inch silicon oxide non-patterned wafers

[0157] Process conditions: head 4.2psi, retaining ring 6.5psi, head 121rpm, pad 119rpm, flow rate 180sccm, ex-situ dressing, 60 seconds polishing

[0158] Each composition according to Examples 1 to 4 and Comparative Example 1 was evaluated with respect to the polishing performance under these conditions, and the results are shown in Tables 1 and Figure 8 and Fig. 9 Shown in.

[0159] (Table 1)

[0160]

[0161] As shown in Table 1, when a tungsten (W) film was polished using the slurry composition for CMP according to the embodiment, a very excellent polishing performance was achieved compared to the slurry composition for CMP according to the comparative example. Figure 8 and Fig. 9 When a tungsten (W) film is polished using the slurry composition for CMP according to the embodiment, less abrasive material remains after polishing than when the slurry composition for CMP according to the comparative example is used, thereby significantly reducing product defects.

[0162] Although the present invention has been described with some exemplary embodiments, it is to be understood that the invention is not limited to the embodiments described herein. Rather, these embodiments are described to cover various modifications and equivalent arrangements included within the scope of the appended claims.

Claims

1. A slurry composition, the slurry composition include: Organic abrasive materials, Wherein, the organic abrasive material includes supramolecular compounds, their homologs or their derivatives.

2. The slurry composition according to claim 1, in, The supramolecular compound has a self-assembled structure formed by two or more structural units, wherein the two or more structural units have a chemical structure of a macrocyclic molecule or polyethylene glycol.

3. The slurry composition according to claim 2, in, The two or more structural units have the chemical structure of the macrocyclic molecule, wherein the macrocyclic molecule includes cucurbituril, calixarene, pillararene, crown ether or porphyrin.

4. The slurry composition according to claim 2, in, The two or more structural units have the chemical structure of the polyethylene glycol, wherein the polyethylene glycol includes a hydrophobic group.

5. The slurry composition according to claim 4, in, The polyethylene glycol further includes an ethylene glycol group, wherein a molecular weight ratio of the ethylene glycol group to the hydrophobic group of the polyethylene glycol is about 1:2 to about 1:

8.

6. The slurry composition according to claim 4, in, The hydrophobic group includes an alkyl group, an alkenyl group, an alkynyl group, an aryl group or a combination thereof.

7. The slurry composition according to claim 4, in, The polyethylene glycol has a structure of Chemical Formula 1: [Chemical formula 1] in: R 1 is a substituted or unsubstituted C1 to C20 alkyl group, and n is an integer from 1 to 100.

8. The slurry composition according to claim 4, in, The two or more structural units have the chemical structure of the polyethylene glycol, wherein the two or more structural units self-assemble to form a micellar structure.

9. The slurry composition according to claim 2, in, The two or more structural units have the chemical structure of the macrocyclic molecule, wherein the macrocyclic molecule includes a molecule having a structure different from that of the macrocyclic molecule, and the molecule is non-covalently bonded to the macrocyclic molecule.

10. The slurry composition according to claim 9, in, The molecule non-covalently bound to the macrocyclic molecule is an amine molecule.

11. The slurry composition according to claim 1, in, The supramolecular compound has a particle size less than or equal to about 100 nm.

12. The slurry composition according to claim 1, in, The content of the inorganic abrasive material in the slurry composition is less than about 0.1 wt % based on the total amount of the slurry composition.

13. The slurry composition according to claim 1, in, The slurry composition is configured for metal polishing.

14. The slurry composition according to claim 1, in, The slurry composition has a pH of about 2 to about 11. 15 . The slurry composition according to claim 1 , further comprising an oxidizing agent, a catalyst, an inhibitor, a chelating agent, a polishing accelerator, a stabilizer, a surfactant, or a combination thereof.

16. A slurry composition, the slurry composition include: About 0.1 wt % to about 10 wt % of an organic abrasive material based on the total amount of the slurry composition, wherein the organic abrasive material comprises a supramolecular compound, a homologue thereof or a derivative thereof, and The slurry composition is free of inorganic abrasive materials.

17. The slurry composition according to claim 16, in, The slurry composition has a pH of about 2 to about 5.

18. A method for manufacturing a semiconductor device, the method include: providing a semiconductor substrate and a polishing pad facing each other; supplying a slurry composition including a supramolecular compound, a homologue thereof, or a derivative thereof between the semiconductor substrate and the polishing pad; as well as A surface of the semiconductor substrate or a surface of a layer formed on the semiconductor substrate is brought into contact with the polishing pad to perform polishing.

19. The method according to claim 18, in, The slurry composition polishes metal wiring on or in the semiconductor substrate.

20. The method according to claim 19, in, The metal wiring includes tungsten.

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