Stable chemical mechanical planarization polishing compositions and methods for high silicon oxide removal rates

Abstract

The chemical mechanical planarization (CMP) polishing composition, method, and system of the present invention provide high removal rates of silicon dioxide to achieve a topography-corrected wafer surface with low electrical conductivity, high stability, and low defects. The CMP polishing composition comprises silica particles and at least one carboxyl group, preferably at least one amino group, -NH 2 , and preferably a unique combination of an amino acid having at least one imidazole group and a silicate.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 269,317, filed March 14, 2022, which is incorporated herein by reference. [Background technology]

[0002] The present disclosure relates to chemical mechanical planarization or polishing slurries (or compositions, or formulations), polishing methods, and polishing systems for performing chemical mechanical planarization in the manufacture of semiconductor devices.

[0003] Chemical Mechanical Planarization ("CMP") polishing is a key process step in the manufacture of integrated circuits, particularly in polishing surfaces to recover selected materials and to planarize structures. As integrated circuit device technology advances, CMP polishing is used in new and different ways to meet the new performance requirements of advanced integrated circuits.

[0004] The present disclosure relates to a barrier chemical mechanical planarization polishing composition (or slurry) used in the manufacture of semiconductor devices, and a polishing method for performing chemical mechanical planarization. In particular, the present disclosure relates to a barrier polishing composition suitable for use in polishing a patterned semiconductor wafer composed of multiple films, such as a metal layer, a barrier film, and an underlying interlayer dielectric (ILD) structure or patterned dielectric layer.

[0005] For example, in a typical barrier process, CMP polishing compositions have been developed targeting high barrier and dielectric film removal rates along with tunable metal layer removal rates.

[0006] In a typical barrier process, the barrier material of a patterned wafer is removed to expose the underlying dielectric. The exposed dielectric is then polished to a specified thickness. In a manufacturing setting, a barrier CMP polishing composition that quickly removes the exposed dielectric to a target thickness can improve throughput of patterned wafers. This throughput efficiency can lead to cost savings in semiconductor manufacturing.

[0007] Prior art providing compositions for metal or barrier CMP includes, for example, U.S. Patent Application Publication No. 2005 / 090104, U.S. Patent Application Publication No. 2010 / 255681, U.S. Patent Application Publication No. 2011 / 053462, U.S. Patent Application Publication No. 2021 / 0253904, and U.S. Patent Application Publication No. 2011 / 081780.

[0008] Conventional barrier CMP slurries are typically designed to have an alkaline pH with good colloidal stability. Another feature of such conventionally designed slurries is that they have high point-of-use (POU) conductivity. This feature often allows for higher material removal rates than would be observed with the same alkaline pH slurry but with a lower POU conductivity.

[0009] In the specific area of ​​barrier CMP, such CMP compositions are designed to remove silicon dioxide at high removal rates, with equally high or lower removal rates of tantalum or tantalum nitride and Cu removal rates targeted to be lower than the silicon dioxide removal rate, and to achieve a topography-corrected wafer surface with low defectivity to prepare the wafer ready for the next downstream process step in microchip manufacturing.

[0010] It should be readily apparent from the foregoing that there remains a need in the art for CMP polishing compositions, methods, and systems that allow the removal rates of various layers, particularly silicon oxide, to be adjusted or tuned during the CMP process to meet the polishing requirements of a particular device. Summary of the Invention

[0011] The subject matter of the present application meets that need by providing chemical mechanical planarization (CMP) polishing compositions, methods, and systems for barrier CMP applications.

[0012] The disclosed CMP polishing compositions have low POU conductivity and a unique combination of fumed silica particles and suitable chemical additives such as soluble silicates, surfactants, bases, and amino acids, e.g., L-histidine, having at least one carboxyl group and at least one amino group -NH2 and an imidazole ring, to provide high removal rates of silicon dioxide (such as TEOS) to achieve a topography-corrected wafer surface with low defects.

[0013] The disclosed CMP polishing composition uses a unique combination of non-spherical, non-surface-modified fumed silica particles.

[0014] In a first major aspect, the CMP composition comprises water; an oxidizer; an abrasive comprising silica particles; a first chemical additive comprising one or more amino acids having at least one carboxyl group, and preferably at least one amino group, -NH2, and preferably at least one imidazole group, and mixtures thereof; and a second chemical additive comprising a silicate; and optionally a corrosion inhibitor; a surfactant; a pH adjuster; and a biocide. The polishing composition has a pH of 7 to 12, 8 to 11.5, or 10 to 11, and the polishing composition has a POU conductivity of 1 mS / cm to 10 mS / cm, 1.5 mS / cm to 9.5 mS / cm, 2 mS / cm to 9 mS / cm, or 2.5 mS / cm to 8.5 mS / cm.

[0015] In another aspect of the first main aspect, the silica particles are fumed silica particles that have not been surface treated or modified with any chemical species, and the fumed silica particles are not covalently bonded to any negatively or positively charged species. The CMP composition of claim 1, wherein the abrasive comprises fumed silica particles present in an amount of about 0.25% to 10.0%, 1% to 8.0%, or 2.0% to 6.0% by weight. In another aspect of the first main aspect, the first chemical additive comprises histidine, glutamic acid, glycine, alanine, aspartic acid, serine, arginine, or tryptophan, or a mixture thereof. In another aspect of the first main aspect, the first chemical additive comprises L-histidine present in an amount of about 0.001% to 1.0%, 0.01% to 0.5%, and about 0.02% to 0.25% by weight. In another embodiment of the first main aspect, the oxidizing agent is hydrogen peroxide. In another embodiment of the first main aspect, the silica particles are selected from the group consisting of colloidal silica, high purity silica, and fumed silica. In another embodiment of the first main aspect, the silicate comprises sodium silicate, potassium silicate, aluminum silicate, calcium silicate, or tetramethylammonium silicate. In another embodiment of the first main aspect, the surfactant is present and is selected from the group consisting of nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and mixtures thereof.

[0016] In a second main aspect, a method of selective chemical mechanical polishing comprises the steps of: a) providing a semiconductor substrate having a surface comprising a first material and at least one second material, the first material being silicon dioxide, such as TEOS or USG (undoped silicon glass), and the second material being copper and a barrier film; b) providing a polishing pad; c) a polishing solution comprising water; one or more amino acids having at least one carboxyl group, and preferably at least one amino group, -NH2, and preferably at least one imidazole group, and mixtures thereof. a first chemical additive; a second chemical additive comprising a silicate; an oxidizing agent; an abrasive comprising silica particles; a corrosion inhibitor; and optionally a surfactant; and a pH adjuster, wherein the polishing composition has a pH of about 9 to about 11, and the polishing composition has a POU conductivity of 1 mS / cm to 10 mS / cm, 1.5 mS / cm to 9.5 mS / cm, 2 mS / cm to 9 mS / cm, or 2.5 mS / cm to 8.5 mS / cm; and d) polishing the surface of the semiconductor substrate to selectively remove the first material.

[0017] In another aspect of the second principal aspect, the pH adjuster is present and is selected from the group consisting of nitric acid, sulfuric acid, potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, and mixtures thereof. In another aspect of the second principal aspect, the polishing agent is present in an amount of about 0.25% to about 5.0% by weight. In another aspect of the second principal aspect, the oxidizing agent is selected from the group consisting of hydrogen peroxide, periodic acid, potassium iodate, potassium permanganate, ammonium persulfate, ammonium molybdate, ferric nitrate, nitric acid, potassium nitrate, ammonia, and mixtures thereof. In another aspect of the second principal aspect, the first chemical additive comprises histidine, glutamic acid, glycine, alanine, aspartic acid, serine, arginine, or tryptophan, or mixtures thereof. In another aspect of the main aspect 2, the first chemical additive comprises L-histidine present in an amount of about 0.001% to 1.0% by weight, 0.01% to 0.5% by weight, and about 0.02% to 0.25% by weight. In another aspect of the main aspect 2, the oxidizing agent is hydrogen peroxide present at about 0.1% to about 3.0% by weight. In another aspect of the main aspect 2, the silica particles comprise alumina or ceria. In another aspect of the main aspect 2, the silicate comprises sodium silicate, potassium silicate, aluminum silicate, calcium silicate, or tetramethylammonium silicate. In another aspect of the main aspect 2, a surfactant is present and is selected from the group consisting of nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and mixtures thereof.

[0018] In a third main aspect, there is provided a method for chemical mechanical planarization of a semiconductor device having at least one surface comprising silicon dioxide, the method comprising the steps of: a. contacting the at least one surface comprising silicon dioxide with a polishing pad; and b. applying to the at least one surface comprising silicon dioxide a polishing pad comprising: water; an oxidizing agent; an abrasive comprising silica particles; a first chemical additive comprising one or more amino acids having at least one carboxyl group, and preferably at least one amino group, -NH2, and preferably at least one imidazole group, and mixtures thereof; a second chemical additive comprising a phosphate; a corrosion inhibitor; and optionally a surfactant; and a pH adjuster, wherein the polishing composition has a pH of about 9 to about 11, and the polishing composition has a POU conductivity of 1 mS / cm to 10 mS / cm, 1.5 mS / cm to 9.5 mS / cm, 2 mS / cm to 9 mS / cm, or 2.5 mS / cm to 8.5 mS / cm; and c. polishing at least one surface comprising silicon dioxide with the polishing composition to at least partially remove the at least one surface comprising silicon dioxide.

[0019] In another aspect of the third main aspect, the pH adjuster is present and is selected from the group consisting of nitric acid, sulfuric acid, potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, and mixtures thereof. In another aspect of the third main aspect, the polishing agent comprises fumed silica present in an amount of about 0.25% to about 5.0% by weight. In another aspect of the third main aspect, the oxidizing agent is selected from the group consisting of hydrogen peroxide, periodic acid, potassium iodate, potassium permanganate, ammonium persulfate, ammonium molybdate, ferric nitrate, nitric acid, potassium nitrate, ammonia, and mixtures thereof. In another aspect of the third main aspect, the oxidizing agent is selected from the group consisting of hydrogen peroxide and urea-hydrogen peroxide. In another aspect of the third main aspect, the oxidizing agent is hydrogen peroxide. In another aspect of the third main aspect, the oxidizing agent is present in an amount of about 0.25% to about 3%. In another aspect of the third main aspect, the silica particles comprise alumina or ceria. In another aspect of main aspect 3, the first chemical additive includes L-histidine present in an amount between about 0.0025% and 2.5%, between 0.025% and 1.25%, and between about 0.05% and 0.625% by weight.

[0020] In a fourth principal aspect, a system for chemical mechanical planarization of a semiconductor device having at least one surface comprises: (1) a semiconductor device having at least one surface having a barrier layer comprising silicon dioxide; (2) an interconnect metal layer selected from the group of copper, tungsten, cobalt, aluminum, or alloys thereof; and (3) a porous or non-porous dielectric layer; a polishing pad; and the chemical mechanical polishing (CMP) composition of any one of claims 1-10.

[0021] In a fifth principal aspect, there is provided a concentrated CMP composition, the composition comprising water; an oxidizer; an abrasive comprising silica particles; a first chemical additive comprising one or more amino acids having at least one carboxyl group, and preferably at least one amino group, -NH2, and preferably at least one imidazole group, and mixtures thereof; and a second chemical additive comprising a silicate; and, optionally, a corrosion inhibitor; a surfactant; a pH adjuster; and a biocide, the composition having a pH of 7-12, 8-11.5, or 10-11, the composition having a conductivity of 1 mS / cm to 15 mS / cm, 7 mS / cm to 14 mS / cm, 9 mS / cm to 13 mS / cm, or 10 mS / cm to 12.5 mS / cm.

[0022] In another aspect of the main aspect 5, the silica particles are fumed silica particles that are not surface treated or modified by any chemical species, and the fumed silica particles are not covalently bonded to any negatively or positively charged species. In another aspect of the main aspect 5, the abrasive comprises fumed silica particles present in an amount of about 0.625% to 25.0% by weight, 2.5% to 20.0% by weight, or 5.0% to 15.0% by weight. In another aspect of the main aspect 5, the first chemical additive comprises histidine, glutamic acid, glycine, alanine, aspartic acid, serine, arginine, or tryptophan, or a mixture thereof. In another aspect of the main aspect 5, the first chemical additive comprises L-histidine present in an amount of about 0.0025% to 2.5% by weight, 0.025% to 1.25% by weight, and about 0.05% to 0.625% by weight. In another aspect of this main aspect 5, the silica particles are selected from the group consisting of colloidal silica, high purity silica, and fumed silica. In another aspect of this main aspect 5, the silicate comprises sodium silicate, potassium silicate, aluminum silicate, calcium silicate, or tetramethylammonium silicate.

[0023] The polished oxide films can be chemical vapor deposition (CVD), plasma enhanced CVD (PECVD), high density deposition CVD (HDP), or spin on oxide films, or undoped silicon glass films. [Brief description of the drawings]

[0024] [Figure 1] FIG. 1 shows the average particle size data over time for concentrated slurry 4A and concentrated slurry 4B. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The subject matter of the present application meets that need by providing chemical mechanical planarization (CMP) polishing compositions, methods, and systems for barrier CMP applications.

[0026] The disclosed CMP polishing compositions have a unique combination of fumed silica particles and suitable chemical additives such as soluble silicates, surfactants, bases, and amino acids, e.g., L-histidine, having at least one carboxyl group and at least one amino group -NH2 and an imidazole ring, to provide high removal rates of silicon dioxide (such as TEOS) to achieve a topography-corrected wafer surface with low defects.

[0027] The barrier CMP slurries of the present invention achieve high material removal rates with low POU conductivity. The benefit of low POU conductivity is that it imparts good colloidal stability to such slurries when they are concentrated above the POU. This allows the barrier CMP slurries to be concentrated from 2.0 to about 5.0 above the POU, which benefits the end user in terms of easier handling, enabling higher throughput, and improved cost of ownership.

[0028] All references cited in this specification, including publications, patent applications, and patents, are hereby incorporated by reference to the same extent as if each reference was individually and specifically indicated to be incorporated by reference and was set forth in its entirety herein.

[0029] In the context of describing the subject matter of this application (particularly in the context of the claims below), the use of the terms "a" and "an" and "the" and similar referents should be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" should be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise indicated. The recitation of ranges of values ​​herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated herein as if it were individually recited herein. All methods described herein can be performed in any suitable order, unless otherwise indicated herein or clearly contradicted by context. Any examples provided herein, or the use of exemplary language (e.g., "such as"), are intended merely to better clarify the subject matter of this application and do not impose limitations on the scope of the claims unless expressly stated. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the claimed subject matter. Use of the term "comprising" in the specification and claims includes the narrower language of "consisting essentially of" and "consisting of."

[0030] Variations of the embodiments described herein will be apparent to those skilled in the art upon reading the foregoing description. The inventors anticipate that those skilled in the art will use such variations as necessary, and the inventors intend for the claimed subject matter to be practiced otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations is encompassed by this disclosure unless otherwise indicated herein or clearly contradicted by context.

[0031] For ease of reference, a "microelectronic device" corresponds to semiconductor substrates, flat panel displays, phase change memory devices, solar panels and other products including solar substrates, photovoltaic devices, and microelectromechanical systems (MEMS) manufactured for use in microelectronic, integrated circuit, or computer chip applications. Solar substrates include, but are not limited to, silicon, amorphous silicon, polycrystalline silicon, single crystal silicon, CdTe, copper indium selenide, copper indium sulfide, and gallium arsenide on gallium. Solar substrates may be doped or undoped. It should be understood that the term "microelectronic device" is not intended to be limiting in any way and includes any substrate that will ultimately become a microelectronic device or microelectronic assembly.

[0032] "Substantially free" is defined herein as less than 0.001% by weight. "Substantially free" also includes 0.000% by weight. The term "free" means 0.000% by weight.

[0033] As used herein, "about" is intended to correspond to ±5%, preferably ±2% of the stated value.

[0034] In all such compositions where a particular component of a composition is discussed with reference to a weight percent range that includes a lower limit of zero, it will be understood that such component may or may not be present in various specific embodiments of the composition, and that when such component is present, such component may be present in concentrations as low as 0.00001 weight percent, based on the total weight of the composition in which such component is used.

[0035] There are several specific aspects of the presently disclosed subject matter.

[0036] In one aspect, a CMP polishing composition is provided that comprises: Fumed silica particles; At least five different chemical additives; Solvent; and Organic small molecule rate enhancing additives; Inorganic rate enhancing additives; pH adjuster; Surfactants; and an oxidizing agent, and optionally a corrosion inhibitor, and the composition has a pH of 7-12, 8-11.5, or 10-11. The composition has a POU conductivity of from 1 mS / cm to 10 mS / cm, from 1.5 mS / cm to 9.5 mS / cm, from 2 mS / cm to 9 mS / cm, or from 2.5 mS / cm to 8.5 mS / cm.

[0037] Silica particles include, but are not limited to, colloidal silica, high purity colloidal silica, and fumed silica. The particles may have any suitable shape, including spherical, non-spherical such as cocoon-shaped, branched, or aggregated silica particles.

[0038] The silica particles are not surface treated or modified with any chemical species, such as nitrogen-containing species, e.g., aminosilanes, and therefore the surface of the particles is not covalently bound to either negatively or positively charged species.

[0039] The mean particle size (MPS) of the silica particles is in the range of 10 nm to 500 nm, preferably in the range of 20 nm to 300 nm, and more preferably in the range of 50 nm to 250 nm. The MPS is measured by dynamic light scattering (DLS).

[0040] The preferred silica particles are fumed silica particles having a multi-aggregated morphology.

[0041] Solvents include, but are not limited to, deionized (DI) water, distilled water, and alcoholic organic solvents.

[0042] The preferred solvent is DI water.

[0043] The first type of chemical additive comprises an amino acid having at least one carboxyl group, and preferably at least one amino group, -NH2, and preferably at least one imidazole group.

[0044] The chemical additives have the general molecular structure shown below. [ka]

[0045] Preferred first type chemical additives include, but are not limited to, histidine, glutamic acid, glycine, alanine, aspartic acid, serine, arginine, and tryptophan.

[0046] The second type of chemical additives include, but are not limited to, silicates, preferably silicates including salts including, but not limited to, sodium silicate, potassium silicate, aluminum silicate, calcium silicate, and tetramethylammonium silicate.

[0047] A third type of chemical additive includes, but is not limited to, alkaline compounds for adjusting pH, such as potassium hydroxide, sodium hydroxide, cesium hydroxide, ammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrabutylammonium hydroxide, tetrabutylphosphonium hydroxide, piperazine, and ethylenediamine.

[0048] A fourth type of chemical additive includes, but is not limited to, surfactants, preferably non-ionic surfactants such as ethoxylated acetylenic diols, such as 2,5,8,11 tetramethyl 6 dodecyne-5,8 diol ethoxylate (Dynol 607).

[0049] A fifth type of chemical additive includes, but is not limited to, oxidizers for oxidizing metal surfaces during CMP, which may include hydrogen peroxide, ammonium persulfate, potassium periodate, and potassium permanganate.

[0050] Optionally, corrosion inhibitors may be used, including, but not limited to, 1H-benzotriazole, 1,2,4-triazole, and amitrole.

[0051] In another aspect, a method is provided for CMP polishing a substrate having at least one surface comprising silicon dioxide using the above-described CMP polishing composition.

[0052] In yet another aspect, a system is provided for CMP polishing a substrate having at least one surface comprising silicon dioxide using the CMP polishing composition described above.

[0053] The polished oxide film can be a chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), high density deposition CVD (HDP), or spin-on oxide film, or an undoped silicon glass film.

[0054] The substrates disclosed above may further include at least one surface containing silicon dioxide, such as TEOS or undoped silicon glass (USG), copper, or both silicon dioxide and copper. The Cu:SiO2 removal selectivity is 1-5, 1-4, 1-3, 1-2, or 0.1-1.

[0055] Other aspects, features and embodiments of the present disclosure will become more fully apparent from the following disclosure and the appended claims.

[0056] The embodiments of the present disclosure may be used alone or in combination with each other.

[0057] The following non-limiting examples are presented to further illustrate the subject matter of the present disclosure.

[0058] CMP Methodology In the examples presented below, CMP experiments were performed using the procedures and experimental conditions set out below.

[0059] Glossary component Fumed silica particles: used as an abrasive having an aggregated branched morphology, a primary particle size of about 10-30 nm, and a secondary particle size in the range of 50-250 nm.

[0060] The particle AeroDisp W7225G was supplied by Evonik Corporation, USA.

[0061] Chemical additives such as L-histidine, L-glutamic acid, and other chemical raw materials were purchased from Sigma-Aldrich (Merck KGaA) of the highest commercial grade and used as received unless otherwise specified.

[0062] Polishing pad: Fujibo H800 was used for CMP and was supplied by Fujibo Ehime Co., Ltd., 272 Oshinden, Saijo-shi, Ehime, 799-1342, Japan.

[0063] Parameters General Å or ​​A: Angstrom - unit of length nm: nanometer - unit of length MPS: Mean particle size, the average of the particle size distribution in a sample as measured by dynamic light scattering ℃: Celsius - unit of temperature BP: Back pressure, unit is psi CMP: Chemical mechanical planarization = chemical mechanical polishing CS: Carrier Speed DF: Downforce: pressure applied during CMP, in psi min:minutes ml: milliliter mV: millivolt psi: pounds per square inch PS: Polishing tool platen rotation speed, in rpm (revolutions per minute) SF: Slurry flow rate, mL / min Wt.%: Weight percent (of the listed ingredients) TEOS: Tetraethyl orthosilicate HDP: TEOS deposited by high density plasma TEOS Removal Rate: TEOS Removal Rate Measured at a Given Down Pressure The down pressure of the CMP tool was 2.5 psi in the examples listed below.

[0064] measurement The films were measured using a ResMap CDE, Model 168, manufactured by Creative Design Engineering, Inc., 20565 Alves Dr., Cupertino, CA, 95014. The ResMap tool is a four-point probe sheet resistance tool. A 49-point diametric scan with 5 mm edge exclusion was performed on the film.

[0065] The films were measured using an Optiprobe 5000 manufactured by Therma-Wave, Inc., 1250 Reliance Way, Fremont, Calif., 94539. The Optiprobe 5000 measures the film thickness of dielectric materials by ellipsometry.

[0066] CMP Tools The CMP tools used were 200 mm Mirra or 300 mm Reflexion manufactured by Applied Materials, 3050 Boweres Avenue, Santa Clara, California, 95054. H800 pads supplied by Fujibo Ehime Co., Ltd., 272 Oshinden, Saijo City, Ehime Prefecture, 799-1342, Japan.

[0067] Polishing conditions: Downforce - 2.5psi Slurry flow rate - 200mL / min Platen Speed ​​- 93 RPM Head Speed ​​- 87 RPM

[0068] Wafer The polishing experiments were performed using TEOS wafers. These blanket wafers were purchased from Silicon Valley Microelectronics, 2985 Kifer Rd., Santa Clara, CA 95051.

[0069] Polishing experiment In the blanket wafer experiments, TEOS blanket wafers were polished under reference conditions.

[0070] All other reagents and solvents were purchased from Sigma-Aldrich (Merck KGaA) of the highest commercial grade and were used as received unless otherwise specified. EXAMPLES

[0071] Example 1 In Example 1, all CMP polishing compositions contained 1.06% potassium silicate, 0.04% potassium hydroxide, 0.002% Dynol 607, and 0.1% hydrogen peroxide.

[0072] In the examples, several different additives were used in Samples 1B-1F compared to 1A.

[0073] Compositions 1B to 1F had point-of-use (POU) conductivities of 6 to 6.37 mS / cm, compared to composition 1A, which had a POU conductivity of 8.04 mS / cm. [Table 1-1] [Table 1-2]

[0074] As shown in Table 1, slurry 1F with additive L-histidine achieves the highest TEOS removal rate at the lowest possible concentration and POU conductivity compared to all other additives. Slurries 1B-1F have lower POU conductivity compared to control 1A. If potassium oxalate is removed and nothing is added in its place, the POU conductivity drops by 2 mS / cm and the TEOS removal rate drops. If alternative additives are added (1C-1F) and an attempt is made to maintain similar POU conductivity, L-histidine (1F) achieves a lower conductivity of about 6 mS / cm and stands out in increasing the removal rate of TEOS compared to the control. Slurries 1B-1F are comparable based on POU conductivity. High formulation conductivity is a widely accepted mechanism for increasing removal rate in barrier slurries. However, the drawback of high conductivity is that it compromises formulation stability. The L-histidine additive achieves better removal rate performance at lower conductivity.

[0075] The TEOS removal rate for Sample 1F is 4% higher than the control Sample 1A, which has a POU conductivity 2 mS / cm higher than Sample 1F. Sample 1F has a 26% higher TEOS removal rate than Sample 1D, which has a POU conductivity of 6.02 mS / cm, almost the same as Sample 1F.

[0076] Example 2 In Example 2, all CMP polishing compositions contained 1.06% potassium silicate, 0.04% potassium hydroxide, 0.002% Dynol 607, and 0.1% hydrogen peroxide.

[0077] In Example 2, compositions 2A and 2C are either fumed or colloidal silica, both having the additive potassium oxalate, and are compared to compositions 2B and 2D, both having the additive L-histidine. [Table 2]

[0078] As shown in Table 2, Samples 2B and 2D with L-histidine have significantly lower POU conductivities when compared to Samples 2A and 2C with potassium oxalate.

[0079] The POU conductivity of sample 2B is 1.7 mS / cm lower than that of sample 2A, and the POU conductivity of sample 2D is 2.26 mS / cm lower than that of sample 2C.

[0080] In Table 2, it is observed that fumed silica compositions 2A and 2B significantly increase the TEOS removal rate over colloidal silica samples 2C and 2D. In sample 2B, the TEOS removal rate increases by 10% when potassium oxalate is replaced with L-histidine. In sample 2D, the TEOS removal rate is only 2% higher than sample 2D, but the POU conductivity is much lower.

[0081] Example 3 In Example 3, all CMP polishing compositions contained 1.06% potassium silicate, 0.04% potassium hydroxide, 0.002% Dynol 607, and 0.1% hydrogen peroxide.

[0082] In addition, sample 3C has the same chemical composition as 3B, but contains a 1% lower concentration of fumed silica than both 3A and 3B.

[0083] These compositions had electrical conductivities at the point of use (POU) ranging from 5.66 to 7.81. [Table 3]

[0084] As shown in Table 3, the substitution of L-histidine for potassium oxalate reduces the POU conductivity of Sample 3B by 2.15 mS / cm from Sample 3A, while the corresponding TEOS removal rate increases by 11%.

[0085] The table also shows that a 1% decrease in fumed silica concentration from Sample 3B to 3C results in a 4.5% decrease in TEOS removal rate. The removal rate of Sample 3C is still higher than that of Sample 3A, indicating that L-histidine, as a replacement for potassium oxalate, can still achieve high TEOS removal rates at lower fumed silica concentrations and lower POU conductivities.

[0086] Example 4 In Example 4, all CMP polishing compositions contained 2.65% potassium silicate, 0.1% potassium hydroxide, and 0.005% Dynol 607, and no hydrogen peroxide. These values ​​represent a 2.5-fold increase in concentration relative to Samples 3A and 3C from Example 3. Similarly, the fumed concentrations in Samples 4A and 4B are increased by a factor of 2.5 relative to their POU concentrations in Samples 3A and 3C of Example 3.

[0087] Samples 4A and 4B were exposed to elevated temperatures of 50° C. for up to 11 days and the average particle size of the fumed silica in the samples was measured at regular intervals during this period. This test is a measure of colloidal stability in the formulation, with an increasing trendline being indicative of colloidal instability. [Table 4-1] [Table 4-2]

[0088] The example shows that concentrated Sample 4B has the additive L-histidine instead of the additive potassium oxalate used in concentrated Sample 4A. Sample 4B also has a 2.5% lower fumed silica concentration compared to Sample 4A based on the data from Table 3. All other components are held at fixed concentrations.

[0089] This example shows that the substitution of L-histidine for potassium oxalate in Sample 4B results in a decrease in slurry conductivity of 3.9 mS / cm.

[0090] Figure 1 shows that Sample 4B remains stable over 11 days at 50°C, while Sample 4A exhibits a 40 nm increase in average particle size over the same time frame. This example clearly shows that the fumed silica in the composition of 4B has a stable MPS at 2.5 times the concentration of POU Sample 3C in Example 3. This is due to the significant decrease in conductivity when concentrated of Sample 4B compared to Sample 4A.

[0091] The embodiments listed above, including the examples, are illustrative of the numerous embodiments that may be made without departing from the scope of the present application. It is contemplated that numerous other configurations of the process may be used and that the materials used in the process may be selected from numerous materials other than those specifically disclosed.

Claims

1. 1. A CMP composition comprising: water; oxidizing agent; an abrasive comprising silica particles; At least one carboxyl group and preferably at least one amino group -NH ２ and preferably one or more amino acids having at least one imidazole group, and mixtures thereof; and a second chemical additive comprising a silicate; and, optionally, Corrosion inhibitors; Surfactants; pH adjuster; Biocides, Including, CMP composition, wherein the polishing composition has a pH of 7 to 12, 8 to 11.5, or 10 to 11, and the polishing composition has a POU conductivity of 1 mS / cm to 10 mS / cm, 1.5 mS / cm to 9.5 mS / cm, 2 mS / cm to 9 mS / cm, or 2.5 mS / cm to 8.5 mS / cm.

2. 2. The CMP composition of claim 1, wherein the silica particles are fumed silica particles that have not been surface treated or modified with any chemical species, and the fumed silica particles are not covalently bonded to either negatively or positively charged species.

3. 10. The CMP composition of claim 1, wherein the abrasive comprises fumed silica particles present in an amount of about 0.25 wt.% to about 10.0 wt.%, about 1.0 wt.% to about 8.0 wt.%, or about 2.0 wt.% to about 6.0 wt.%.

4. 2. The CMP composition of claim 1, wherein the first chemical additive comprises histidine, glutamic acid, glycine, alanine, aspartic acid, serine, arginine, or tryptophan, or a mixture thereof.

5. 5. The CMP composition of claim 4, wherein the first chemical additive comprises L-histidine present in an amount ranging from about 0.001 wt % to about 1.0 wt %, from about 0.01 wt % to about 0.5 wt %, or from about 0.02 wt % to about 0.25 wt %.

6. The CMP composition of claim 1 , wherein the oxidizing agent is hydrogen peroxide.

7. 2. The CMP composition of claim 1, wherein the silica particles are selected from the group consisting of colloidal silica, high purity silica, and fumed silica.

8. 2. The CMP composition of claim 1, wherein the silicate comprises sodium silicate, potassium silicate, aluminum silicate, calcium silicate, or tetramethylammonium silicate.

9. 2. The CMP composition of claim 1, wherein the surfactant is present and is selected from the group consisting of nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and mixtures thereof.

10. 1. A method for selective chemical mechanical polishing, comprising: a) providing a semiconductor substrate having a surface containing a first material and at least one second material, the first material being silicon dioxide such as TEOS or USG (undoped silicon glass) and the second material being copper and a barrier film; b) providing a polishing pad; c) water; At least one carboxyl group and preferably at least one amino group -NH ２ and preferably one or more amino acids having at least one imidazole group, and mixtures thereof; a second chemical additive comprising a silicate; oxidizing agent; an abrasive comprising silica particles; Corrosion inhibitors; and, optionally, Surfactants; pH adjuster, providing a chemical mechanical polishing composition comprising: The polishing composition has a pH of about 9 to about 11. the polishing composition has a POU conductivity of 1 mS / cm to 10 mS / cm, 1.5 mS / cm to 9.5 mS / cm, 2 mS / cm to 9 mS / cm, or 2.5 mS / cm to 8.5 mS / cm; and d) polishing the surface of the semiconductor substrate to selectively remove the first material; A method comprising:

11. 11. The method of claim 10, wherein the pH adjuster is present and is selected from the group consisting of nitric acid, sulfuric acid, potassium hydroxide, sodium hydroxide, ammonia, tetraethylammonium hydroxide, ethylenediamine, piperazine, polyethyleneimine, and mixtures thereof.

12. The method of claim 10, wherein the abrasive is present in an amount of about 0.25% to about 5.0% by weight.

13. 11. The method of claim 10, wherein the oxidizing agent is selected from the group consisting of hydrogen peroxide, periodic acid, potassium iodate, potassium permanganate, ammonium persulfate, ammonium molybdate, ferric nitrate, nitric acid, potassium nitrate, ammonia, and mixtures thereof.

14. 11. The method of claim 10, wherein the first chemical additive comprises histidine, glutamic acid, glycine, alanine, aspartic acid, serine, arginine, or tryptophan, or a mixture thereof.

15. 15. The method of claim 14, wherein the first chemical additive comprises L-histidine present in an amount of about 0.001% to 1.0% by weight, 0.01% to 0.5% by weight, and about 0.02% to 0.25% by weight.

16. The method of claim 10, wherein the oxidizing agent is hydrogen peroxide present at about 0.1% to about 3.0% by weight.

17. The method of claim 10 , wherein the silica particles comprise alumina or ceria.

18. 11. The method of claim 10, wherein the silicate comprises sodium silicate, potassium silicate, aluminum silicate, calcium silicate, or tetramethylammonium silicate.

19. 11. The method of claim 10, wherein the surfactant is present and is selected from the group consisting of nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, and mixtures thereof.

20. 1. A system for chemical mechanical planarization of a semiconductor device having at least one surface, comprising: (1) a barrier layer comprising silicon dioxide; (2) an interconnect metal layer selected from the group of copper, tungsten, cobalt, aluminum, or alloys thereof; and (3) a porous or non-porous dielectric layer; said semiconductor device having at least one surface; A polishing pad; A system comprising the chemical mechanical polishing (CMP) composition of any one of claims 1 to 9.

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