A polishing material composition, a method for producing a semiconductor device

Abstract

The application discloses a kind of abrasive material compositions, the preparation method of semiconductor device, it is related to the field of semiconductor technology, including polyglycerol compound, abrasive material and auxiliary agent: wherein, the average polymerization degree of the polyglycerol compound is 6~40, the branching degree of the polyglycerol compound is below 0.20, the proportion of primary hydroxyl in the skeleton of the polyglycerol compound accounts for 90% or more of total number of hydroxyl, above-mentioned polyglycerol ensures that molecular chain has highly linear characteristic, can be more stable, orderly adsorbed on the surface of abrasive particle when using, to improve the dispersion stability of abrasive particle, finally significantly reduce defect and micro scratch in oxide film final precision polishing and other planarization process, improve surface roughness and keep excellent polishing performance.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to an abrasive material composition and a method for preparing semiconductor devices. Background Technology

[0002] With the increasing sophistication and multilayer wiring of semiconductor devices, chemical mechanical polishing (CMP) has become a key process for achieving surface planarization of interlayer insulating films, wiring layers, and barrier metal layers. CMP abrasive compositions typically contain abrasive particles such as colloidal silica, as well as various additives including pH adjusters, dispersants, corrosion inhibitors, and surfactants. In oxide film CMP processes, especially in the final fine polishing stage of shallow trench isolation (STI) structures, the requirements for low defect rates and excellent surface roughness far outweigh those for removal rates. However, in intermediate polishing and interlayer dielectric planarization stages, a balance must be struck between production efficiency and polishing performance.

[0003] To improve the dispersion stability of grinding particles and reduce scratches, existing technologies often introduce surfactants or polymeric dispersants, such as polyglycerol derivatives. However, traditional polyglycerol is mostly prepared by direct polymerization of glycidyl ether or thermal condensation of glycerol, resulting in complex and non-uniform molecular structures, which limits its performance as a dispersant or surfactant.

[0004] Therefore, the industry urgently needs to solve the problem of insufficient dispersion stability and easy scratching of traditional nonlinear polyglycerol derivatives in CMP applications, so as to achieve the goal of reducing defects and improving surface roughness in the final fine polishing of oxide films, and maintaining good polishing performance in other planarization processes. Summary of the Invention

[0005] The main objective of this invention is to provide a method for preparing abrasive material compositions and semiconductor devices, aiming to solve the problems of insufficient dispersion stability and easy scratching of traditional nonlinear polyglycerol derivatives in CMP applications.

[0006] To achieve the above objectives, the present invention provides an abrasive material composition comprising polyglycerol, an abrasive material, and an additive: The polyglycerol has an average degree of polymerization of 6 to 40, a branching degree of less than 20%, and a primary hydroxyl group in the polyglycerol backbone accounting for more than 90% of the total number of hydroxyl groups.

[0007] In one embodiment, the polyglycerol has an average degree of polymerization of 6 to 20; and / or, the primary hydroxyl ratio of the polyglycerol backbone is 90 to 100%.

[0008] In one embodiment, the abrasive material composition comprises, by weight percentage: Polyglycerol 0.001~5%; Abrasive material 1~30%; Additives 0.1~0.5%; The rest is water.

[0009] In one embodiment, the polyglycerol compound includes a polyglycerol derivative, which is prepared by an ether addition reaction of the polyglycerol with an alkyl glycidyl ether or an alkoxy glycidyl ether having 6 to 24 carbon atoms.

[0010] In one embodiment, the polyglycerol compound includes a polyglycerol derivative formed by esterification of polyglycerol with an average degree of polymerization of 4 to 40 and a fatty acid with 6 to 24 carbon atoms.

[0011] In one embodiment, the abrasive material comprises at least one selected from colloidal silica, precipitated silica, fumed silica, alumina, cerium oxide, zirconium oxide, and silicon nitride; and / or, The abrasive material includes colloidal silica, and the average particle size of the colloidal silica is 0.01 to 0.1 μm.

[0012] The present invention provides a method for fabricating a semiconductor device, comprising a polishing material composition as described in any of the preceding claims, and performing chemical mechanical polishing on the polished layer of a semiconductor substrate.

[0013] In one embodiment, the chemical mechanical polishing includes a final fine polishing process of the oxide film applied in the shallow trench isolation structure formation process.

[0014] In one embodiment, the chemical mechanical polishing includes an intermediate polishing process for the oxide film or an interlayer dielectric planarization process.

[0015] The technical solution of this invention fundamentally solves the technical problems of insufficient dispersion stability and easy scratching of traditional nonlinear polyglycerol derivatives in CMP applications by adopting a specific polyglycerol compound structure at the molecular level. Specifically, this invention significantly improves the structural uniformity and regularity of the molecules by strictly controlling the average degree of polymerization (6~40), the degree of branching (below 0.20), and the proportion of primary hydroxyl groups in the backbone of the polyglycerol compound to more than 90% of the total number of hydroxyl groups, overcoming the defects of complex and non-uniform structures of traditional polyglycerol compounds; at the same time, its highly regular linear molecular conformation enables it to form a dense, uniform, and high-strength steric hindrance protective layer on the surface of grinding particles. This structural uniformity (low branching and high primary hydroxyl ratio) ensures that the molecular chains can be anchored to the abrasive surface in an orderly and compact manner, fundamentally inhibiting the agglomeration and hard collision of abrasive grains under the polishing shear force. This allows the abrasive grains to mainly use smooth rolling friction on the wafer surface instead of destructive scraping. At the same time, this stable dispersion system and excellent anti-redeposition ability ensure that the chemical-mechanical synergy of the polishing interface proceeds smoothly, thereby efficiently removing material while controlling the surface roughness at an extremely low level, ultimately achieving excellent polishing performance with no scratches and low defects. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 Five structural diagrams of polyglycerol obtained in the synthetic examples of this invention are shown. Figure 2 The image shows the 13C-NMR spectrum of polyglycerol A in the synthesis example of this invention. Figure 3 The image shows the 13C-NMR spectrum of polyglycerol B in the synthesis example of this invention. Figure 4 The image shows the 13C-NMR spectrum of polyglycerol C in the synthesis example of this invention. Figure 5 The image shows the 13C-NMR spectrum of polyglycerol D in the synthesis example of this invention. Figure 6 This is the 13C-NMR spectrum of polyglycerol E in the synthesis example of this invention; Figure 7 The image shows the 13C-NMR spectrum of polyglycerol F in the synthesis example of this invention. Figure 8This is the 13C-NMR spectrum of polyglycerol G in the synthesis example of this invention.

[0018] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0021] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0022] To improve the dispersion stability of grinding particles and reduce scratches, existing technologies often introduce surfactants or polymeric dispersants, such as polyglycerol derivatives. However, traditional polyglycerol is mostly prepared by direct polymerization of glycidyl ether or thermal condensation of glycerol, resulting in complex and non-uniform molecular structures, which limits its performance as a dispersant or surfactant.

[0023] Therefore, the industry urgently needs to solve the problem of insufficient dispersion stability and easy scratching of traditional nonlinear polyglycerol derivatives in CMP applications, so as to achieve the goal of reducing defects and improving surface roughness in the final fine polishing of oxide films, and maintaining good polishing performance in other planarization processes.

[0024] In view of this, an abrasive material composition is provided, comprising a polyglycerol compound, an abrasive material, and an additive: wherein the polyglycerol compound has an average degree of polymerization of 6 to 40, a degree of branching of the polyglycerol compound is less than 0.20, and the proportion of primary hydroxyl groups in the backbone of the polyglycerol compound to the total number of hydroxyl groups is more than 90%.

[0025] The technical solution of this invention fundamentally solves the technical problems of insufficient dispersion stability and easy scratching of traditional nonlinear polyglycerol derivatives in CMP applications by adopting a specific polyglycerol compound structure at the molecular level. Specifically, this invention significantly improves the structural uniformity and regularity of the molecules by strictly controlling the average degree of polymerization (6~40), degree of branching (below 0.20), and the proportion of primary hydroxyl groups in the backbone of the polyglycerol compound to more than 90% of the total number of hydroxyl groups, thus overcoming the defects of complex and non-uniform structures of traditional polyglycerol compounds. At the same time, its highly regular linear molecular conformation and abundant primary hydroxyl active sites enable it to form a dense, uniform, and high-strength steric hindrance protective layer on the surface of the grinding particles. This structural uniformity ensures that the molecular chains can be anchored to the abrasive surface in an orderly and compact manner, fundamentally suppressing the agglomeration and hard collision of abrasive grains under the action of polishing shear force. This allows the abrasive grains to mainly use smooth rolling friction on the wafer surface instead of destructive scraping. At the same time, this stable dispersion system and excellent anti-redeposition ability ensure that the chemical-mechanical synergy of the polishing interface proceeds smoothly, thereby efficiently removing material while controlling the surface roughness at an extremely low level, ultimately achieving excellent polishing performance with no scratches and low defects.

[0026] Furthermore, the primary hydroxyl ratio describes the relative abundance of primary hydroxyl groups in the total hydroxyl groups of a molecule. Currently, traditional nonlinear polyglycerols have many branches and complex structures, which easily form disordered conformations when adsorbed onto the surface of grinding particles, resulting in poor steric hindrance and an inability to effectively prevent particle aggregation. In contrast, the primary hydroxyl ratio in the backbone is as high as 90% or more, giving the polyglycerol molecule a highly ordered linear structure. This ordered linear molecule can anchor itself to the surface of grinding particles in a more ordered and compact manner, forming a uniform and dense protective layer, thereby providing a strong steric hindrance effect and fundamentally inhibiting the aggregation of grinding particles.

[0027] It should be noted that, in this invention, the 'backbone of polyglycerol' refers to the continuous main chain structure formed by the interconnection of glycerol units through ether bonds (-COC-) in the polyglycerol molecule. This backbone is the core connecting part of the polyglycerol molecule, distinct from the branched structures extending outward from the backbone and the terminal hydroxyl groups (-OH) attached to carbon atoms. Specifically, "primary hydroxyl groups in the backbone" specifically refers to primary hydroxyl groups (-CH2OH) directly attached to the carbon atoms of the polyglycerol backbone; while 'non-backbone hydroxyl groups' refer to hydroxyl groups located at the ends or inside the branches.

[0028] Furthermore, the 'polyglycerol compounds' mentioned herein include polyglycerol itself, as well as polyglycerol derivatives derived from polyglycerol.

[0029] Furthermore, the polyglycerol or polyglycerol derivatives used in this invention are not limited to linear polyglycerol obtained by the EEGE method, but are limited to substances whose branching degree, primary hydroxyl ratio, and molecular weight distribution are within the range specified in this invention. Specifically, if polyglycerol is obtained by the EEGE method, linear polyglycerol in which all glycerol units are primary hydroxyl groups can be synthesized by ring-opening polymerization of hydroxyl-protected glycidyl monomers (such as ethoxyethyl glycidyl ether, EEGE) and then deprotecting them under acidic conditions. This linear polyglycerol contains almost no branched structure and has both a linear polyether backbone similar to polyethylene glycol and a multi-primary hydroxyl structure, thus exhibiting a uniform molecular structure and high material stability and functional design freedom.

[0030] In some embodiments, the polyglycerol compound has an average degree of polymerization of 6 to 20.

[0031] This invention limits the degree of polymerization to 6-20, ensuring that the molecular chains provide sufficient steric hindrance to maintain particle dispersion without causing excessive entanglement or increasing the viscosity of the polishing slurry due to excessive chain length during high-shear CMP polishing. This optimal molecular size ensures that the abrasive particles maintain an independent and smooth rolling friction state during polishing, rather than a rough sliding friction, thereby effectively avoiding the generation of micro-scratches and ultimately achieving the goal of reducing defects and improving surface roughness. Specifically, the average degree of polymerization of the polyglycerol compound can be 6, 8, 10, 15, or 20, etc.

[0032] The high proportion of primary hydroxyl groups demonstrates that the polyglycerol backbone exhibits high linearity and structural uniformity, which reduces the difference in thickness and density between the abrasive material particles and the adsorption layer formed on the polished surface, making the interfacial mechanical state during the polishing process more uniform, thereby significantly reducing micro-scratches and improving the flatness of the wafer surface. The proportion of primary hydroxyl groups in the polyglycerol compound can be 90%, 95%, 98%, 99%, or 100%, etc.

[0033] In some embodiments, the abrasive material composition comprises, by weight percentage: Polyglycerol compounds 0.001~5%; Abrasive material 1~30%; Additives 0.1~0.5%; The rest is water.

[0034] In the technical solution of this invention, within the aforementioned range, the content of polyglycerol compounds is sufficient to form a complete monomolecular or multimolecular protective layer on the surface of the abrasive particles. If the content is too low, it cannot completely cover the particles, leading to unstable dispersion; if the content is too high, it may introduce micelles, affecting the rheological properties of the polishing slurry. This range effectively inhibits particle agglomeration and significantly reduces particle residue and scratches after polishing.

[0035] In some embodiments, the polyglycerol compound includes a polyglycerol derivative, which is prepared by an ether addition reaction of polyglycerol with an average degree of polymerization of 4 to 40 and an alkyl glycidyl ether or an alkoxy glycidyl ether having 6 to 24 carbon atoms, wherein the number of carbon atoms can be 6, 10, 15, 20 or 24.

[0036] Polyglycerol derivatives form a uniform molecular layer upon adsorption onto the surface of abrasive particles and the surface being polished. The layer thickness is prevented from excessively increasing due to the self-constraint of the linear framework. Therefore, effective contact between the abrasive particles and the substrate is maintained, promoting the polishing reaction while mitigating the localization of abrasive loads. This self-constrained adsorption layer significantly reduces scratches without compromising the polishing rate.

[0037] The technical solution of this invention utilizes esterification to introduce fatty acid chains, leveraging their unique surface-active properties to optimize the polishing interface environment. Specifically, polyglycerol fatty acid esters are excellent nonionic surfactants. During CMP (Chemical Mechanical Polishing), they can effectively emulsify and disperse hydrophobic organic contaminants or metal debris stripped from the wafer surface, preventing their redeposition onto the wafer surface and thus reducing surface defects.

[0038] In some embodiments, the abrasive material includes at least one of colloidal silica, precipitated silica, fumed silica, alumina, cerium oxide, zirconium oxide, and silicon nitride.

[0039] It can match different polishing materials (such as oxides, metals, ceramics, etc.) and process requirements. For example, colloidal silicon dioxide has a spherical shape and medium hardness, which can minimize the risk of wafer scratches during polishing. It is very suitable for fine polishing of semiconductor silicon wafers, optical lenses and dielectric layers. Using the above-mentioned abrasive materials can minimize the risk of wafer scratches through gentle mechanical action in fine polishing, and can also achieve high selective removal by utilizing the chemical synergistic effect of specific abrasives (such as cerium oxide). Thus, while ensuring a high material removal rate, it ensures excellent surface flatness and strictly controls micro-scratch defects.

[0040] In some embodiments, the abrasive material includes colloidal silica, the average particle size of which includes 0.01 to 0.1 μm. Colloidal silica with an average particle size of 0.01 to 0.1 μm is selected because it has good sphericity, narrow particle size distribution and moderate hardness, which can minimize mechanical scratches on the soft dielectric layer (such as silicon oxide) while ensuring a certain cutting force, making it particularly suitable for fine polishing processes. The average particle size of the colloidal silica can be 0.01 μm, 0.05 μm, 0.09 μm or 0.1 μm.

[0041] In some embodiments, at least one of the additives, a pH adjuster and a preservative, wherein water can be used as a dispersion medium, the pH adjuster is used to maintain the stability of the zeta potential, and the preservative can prevent microbial growth that could lead to slurry deterioration, thereby ensuring the chemical and physical stability of the grinding material composition during storage and use, and extending the product's service life.

[0042] The present invention provides a method for fabricating a semiconductor device, comprising a polishing material composition as described in any of the preceding claims, and performing chemical mechanical polishing on the polished layer of a semiconductor substrate.

[0043] This approach introduces polyglycerol and its derivatives, with their specific structures, as core dispersants into the CMP process, fundamentally optimizing the physicochemical environment of the polishing interface. Due to the highly ordered linear structure and extremely narrow molecular weight distribution of this polyglycerol component, it can form a dense and uniform steric hindrance layer on the surface of the abrasive particles, significantly improving the dispersion stability of the slurry. In actual polishing, this excellent dispersibility effectively prevents the abrasive particles from agglomerating, ensuring that the abrasive particles primarily undergo smooth rolling friction on the wafer surface. This, in turn, significantly reduces micro-scratches and macro-scratches on the wafer surface while maintaining a high material removal rate, thereby improving the overall yield of semiconductor devices.

[0044] Furthermore, the chemical mechanical polishing includes a final fine polishing step of the oxide film in the shallow trench isolation structure formation process. The final fine polishing of the STI process is a key step that determines the global flatness of the chip surface and the quality of subsequent photolithography. With the high stability of the paste and the gentle mechanical action, the abrasive material composition prepared by the present invention can completely remove the surface oxide film while controlling the surface roughness at the sub-nanometer level (e.g., Ra < 0.1 nm), and effectively avoid dish-shaped depressions and erosion defects in the trench area, providing a perfect substrate for subsequent high-precision photolithography and multilayer wiring.

[0045] Furthermore, the chemical mechanical polishing includes an intermediate polishing process for the oxide film or an interlayer dielectric (ILD) planarization process. In the intermediate polishing process or the interlayer dielectric (ILD) planarization process for the oxide film, this technical solution utilizes the polyglycerol component in the abrasive material composition to maintain a high concentration of effective dispersion of abrasive particles, ensuring that the polishing slurry achieves rapid wetting and uniform distribution on complex morphological surfaces with high steps, thereby significantly improving the planarization efficiency of multilayer wiring structures and the reliability of devices.

[0046] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the following embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0047] Preparation of experimental materials Different types of polyglycerol are available, including the following: Synthesis Example 1: The linear polyglycerol A (degree of polymerization) synthesized using EEGE is shown in the following steps: Under a nitrogen atmosphere, 1.63 g (0.062 mol) of tetrabutylammonium hydroxide as an initiator was added to a dry three-necked flask, followed by 100 parts by weight of anhydrous tetrahydrofuran (THF), and the mixture was cooled to 0 °C. Then, 91.8 g (0.62 mol) of ethoxyethyl glycidyl ether (EEGE) was added dropwise over 2 hours, followed by stirring at 35 °C for 4 hours to confirm that the monomer was almost completely converted.

[0048] After the reaction was complete, dilute hydrochloric acid was added to neutralize the residual alkali, and the organic layer was separated. After removing the solvent by vacuum distillation, the obtained poly(EEGE) was dissolved in methanol, and salts were removed using an ion exchange resin. The solvent was removed again by vacuum distillation to obtain a colorless to pale yellow viscous liquid of poly(EEGE) (yield 90%).

[0049] 100 mL of 1 mol / L hydrochloric acid aqueous solution was added to the obtained poly(EEGE), and the mixture was stirred at 30 °C for 24 hours to perform acidic deprotection of the 1-ethoxyethyl protecting group. After the reaction, the reaction solution was concentrated under reduced pressure, diluted with a large amount of ethanol, and then passed through an anion exchange resin column to remove the acid. The solvent was removed by distillation, and the residue was dried under reduced pressure to obtain a linear polyglycerol with only primary hydroxyl groups in all glycerol units, which was a colorless viscous liquid (yield 85%).

[0050] The average degree of polymerization of polyglycerol was calculated to be approximately 10 based on the hydroxyl value. Continue... 13 C-NMR analysis confirmed that the degree of branching was 0.12 and the primary hydroxyl ratio was 98%, indicating that it was a linear polyglycerol composed almost entirely of primary hydroxyl groups.

[0051] Synthesis Example 2: 2-Ethylhexyl glycidyl ether adduct (polyglycerol B) synthesized using linear polyglycerol A. 100.0 g of the linear polyglycerol A (average degree of polymerization approximately 10) obtained in Synthesis Example 1 was placed in a three-necked flask equipped with a stirrer, thermometer, and dropping funnel. Under a nitrogen atmosphere, the mixture was heated to 80°C to make it a homogeneous liquid.

[0052] Prepare 24.5 g of 2-ethylhexyl glycidyl ether (2-EHGE) (equivalent to 10 moles of linear polyglycerol) in a separate container, preheat it to 80°C, and then add it dropwise to the flask through a dropping funnel over 2 hours. During and after the addition, maintain the internal temperature at 85-90°C and stir the mixture for 5 hours.

[0053] After the addition was complete, 1.0 g of 48% sodium hydroxide aqueous solution was added as a catalyst, and the solution was allowed to disperse evenly over 15 minutes. Then, while removing the generated water and low-boiling-point components under reduced pressure (approximately 20 kPa), the reaction was continued at 90 °C for 2 hours. The reaction progress was confirmed by monitoring the decrease in the IR absorption peak of the epoxy groups and measuring the acid value. The reaction was stopped when the unreacted epoxy groups decreased to near the detection limit.

[0054] After the reaction was complete, 85% phosphoric acid aqueous solution was added dropwise to adjust the pH to 6-7, and the mixture was cooled to room temperature. The reaction solution was concentrated under reduced pressure, diluted with a large amount of isopropanol (500 mL), and then passed through an anion exchange resin column to remove inorganic salts. Isopropanol was removed from the eluent by reduced pressure distillation, and the residue was dried under reduced pressure at 50°C overnight to obtain a linear polyglycerol-2-ethylhexyl glycidyl ether adduct, namely polyglycerol A-1, which is a pale yellow viscous liquid (yield approximately 80%).

[0055] Polyglycerol A-1 was analyzed by 13C-NMR to determine the signals on the polyglycerol backbone and the signals derived from 2-ethylhexyl groups. The results confirmed that the degree of branching of the polyglycerol backbone was 0.12, the primary hydroxyl ratio was 98%, the secondary hydroxyl ratio was 2%, and the linear polyglycerol backbone structure was maintained.

[0056] Synthesis Examples 3, 5, and 7: Similar to Synthesis Example 1, only the amount of tetrabutylammonium hydroxide added as the initiator was changed (0.10 mmol, 0.031 mmol, and 0.015 mmol), yielding linear polyglycerols with degrees of polymerization of 6, 20, and 40, respectively. These were designated as B (89% yield), C (87% yield), and D (82% yield), respectively.

[0057] Synthetic Examples 4, 6, and 8: Using the same preparation method as in Synthetic Example 2, linear polyglycerol was reacted with an equimolar amount of 2-ethylhexyl glycidyl ether to obtain linear polyglycerol-2-ethylhexyl glycidyl ether adducts with degrees of polymerization of 6, 20, and 40, respectively. These were named B-1 (80% yield), C-1 (82% yield), and D-1 (80% yield), respectively.

[0058] Synthesis Example 9: Synthesis of Polyglycerol E Derived from Glycidyl Under a nitrogen atmosphere, 92 g (1 mol) of glycerol and 1.0 g (0.018 mol) of potassium hydroxide were added to a dry stainless steel reactor, and the mixture was heated to 120 °C and dried for 30 minutes. Subsequently, while maintaining an internal temperature of 130 °C, 667 g (9 mol) of glycidyl ether was added dropwise over 4 hours. During the dropwise addition, cooling measures were taken as needed to suppress the heat generated by the reaction.

[0059] After the addition was complete, the temperature inside the reactor was raised to 140°C, and stirring was continued for 4 hours. During the reaction, the generated low-boiling-point components were removed by distillation under reduced pressure (approximately 30 kPa), while the reaction was allowed to continue. The reaction progress was monitored by changes in viscosity and hydroxyl value.

[0060] After the reaction was complete, the reaction solution was cooled to room temperature and neutralized to pH 6-7 with dilute hydrochloric acid. The resulting neutralized solution was distilled under reduced pressure to remove water and volatile components. Subsequently, the resulting viscous liquid was filtered through a ceramic filter to remove insoluble matter, yielding pale yellow polyglycerol E (yield approximately 80%).

[0061] The hydroxyl value of polyglycerol E was determined, and the average degree of polymerization was calculated to be approximately 10 using a formula. 13C-NMR analysis in heavy water was performed to determine the degree of branching and the primary / secondary hydroxyl ratio. The results showed a branching degree of 0.33, a primary hydroxyl ratio of approximately 29%, and a secondary hydroxyl ratio of approximately 71%. This indicates that even among linear polymers, different types of hydroxyl groups can lead to performance differences. The linear polyglycerol A used in this invention has a primary hydroxyl ratio of 95%–100%, while polyglycerol E has a significantly lower primary hydroxyl ratio.

[0062] Synthesis Example 10: Synthesis of Polyglycerol F derived from the thermal shrinkage of glycerol Under a nitrogen atmosphere, 100.0 g of glycerol and 0.5 g of sodium hydroxide were added to a four-necked flask. A mechanical stirrer, a thermometer, and a reflux condenser equipped with a Dean-Stark water separator were installed. While heating to 230 °C, the generated water was continuously separated and removed, and the reaction was carried out within this temperature range for 6 hours. During the reaction, the increase in viscosity and the amount of water generated were monitored.

[0063] After the reaction, the system was cooled to room temperature, and the residual alkali was neutralized with an aqueous sodium carbonate solution. Water and volatile components were removed by distillation under reduced pressure (approximately 20 kPa). The resulting viscous liquid was filtered through a 0.5 μm filter to remove solid components from the catalyst, yielding a light brown polyglycerol F (yield approximately 75%).

[0064] The hydroxyl value of polyglycerol F was determined, and the average degree of polymerization was calculated using (Equation 1), which was approximately 10. The degree of branching and the primary / secondary hydroxyl ratio were determined by 13C-NMR analysis. The results showed that the degree of branching was approximately 0.50, the primary hydroxyl ratio was approximately 64%, and the secondary hydroxyl ratio was approximately 36%.

[0065] Synthesis Example 11: Synthesis of Polyglycerol G Derived from Glycidol Under a nitrogen atmosphere, 92 g (1 mol) of glycerol was added to a dry reactor, and the temperature was raised to 120 °C. Subsequently, 666.7 g (9 mol) of glycidyl ether and 10 g of phosphoric acid were added dropwise over 12 hours. After the addition was complete, the mixture was stirred at 120 °C for another hour. After the reaction was complete, the reaction solution was cooled to room temperature to obtain pale yellow polyglycerol G in 80% yield.

[0066] The hydroxyl value of polyglycerol G was determined, and the average degree of polymerization was calculated using a formula, which was approximately 10. Dissolving it in heavy water and performing 13C-NMR analysis, the primary / secondary hydroxyl ratio was determined. The results showed that the degree of branching was approximately 0.42, confirming it as highly branched polyglycerol; the primary hydroxyl ratio was approximately 63%, and the secondary hydroxyl ratio was approximately 37%.

[0067] Synthetic Examples 12-14: Preparation of 2-ethylhexyl glycidyl ether adducts using various polyglycerols Using 100.0 g of polyglycerol E obtained in Synthesis Example 9, polyglycerol F obtained in Synthesis Example 10, and polyglycerol G obtained in Synthesis Example 11, respectively, 2-ethylhexyl glycidyl ether of equal molar amount to polyglycerol was added dropwise under the same conditions as in Synthesis Example 2, and the reaction was carried out at 90 °C to prepare the corresponding polyglycerol derivatives E-1, F-1, and G-1.

[0068] The obtained derivatives E-1, F-1, and G-1 were subjected to GPC and ¹³C-NMR measurements, and the results confirmed that they maintained the branching degree and primary / secondary hydroxyl ratio characteristics of the starting polyglycerols E, F, and G, respectively. Specifically, E-1 had a branching degree of 0.33 and a primary hydroxyl ratio of approximately 29%, F-1 had a branching degree of approximately 0.19 and a primary hydroxyl ratio of approximately 36%, and G-1 had a branching degree of approximately 0.50 and a primary hydroxyl ratio of approximately 64%.

[0069] The test results of the polyglycerols obtained in the above synthetic examples 1-14 are shown in Table 1. The test methods are as follows: 1. The degree of branching, primary hydroxyl ratio, and secondary hydroxyl ratio of polyglycerol and its derivatives are obtained under the following conditions. 13 The ¹³C-NMR spectrum was calculated, and the ¹³C-NMR analysis was performed as follows: 200 mg of linear polyglycerol was dissolved in 0.6 mL of heavy water and transferred to an NMR tube for determination. An external field-locked signal calibrated to the tetramethylsilane (TMS) equivalent position was used as needed, with acetone (30.89 ppm) as the external standard to correct the chemical shift. A 100 MHz ¹³C-NMR instrument was used in single-pulse ¹H decoupling mode for determination. Based on the carbon signal integral values ​​corresponding to the bonding mode with the polyglycerol backbone (including 1,3-bonded main chain, 1,2-bonded and branched structures), the degree of branching, primary hydroxyl ratio, and secondary hydroxyl ratio were calculated respectively. Specifically, the polyglycerols prepared in the above 14 synthetic examples contain 5 structures (D, L13, L14, T1, T2, see appendix) Figure 1 The spectra of polyglycerols A, B, C, D, E, F, and G in the synthesis examples of this invention are as follows: Figures 2 to 8 As shown, the polyglycerol described above will exhibit peaks A~H in its carbon NMR spectrum, which are identified as carbon atoms at specific positions within each structure. The proportions of the five structures D, L13, L14, T1, and T2 are calculated using the integral ratios of each peak. The proportion of D-structures: D = {C}, where {C} is the integral area of ​​peak C; The proportion of L13 structure: L13 = {I}, where {I} is the integral area of ​​peak I; The proportion of L14 structure: L14 = {D} / 2, where {D} is the integral area of ​​peak D; The degree of branching is calculated using the following formula: DB = 2D / (2D + L13 + L14); Based on the proportions of each structure in polyglycerol, the proportion of primary hydroxyl groups is calculated as L13 / (L13+L14), and the proportion of secondary hydroxyl groups is calculated as L14 / (L13+L14).

[0070] 2. The average degree of polymerization of polyglycerol and polyglycerol derivatives is calculated based on the hydroxyl value using the following formula.

[0071] Average degree of polymerization = (112.2 × 10^3 - 18 × hydroxyl value) / (74 × hydroxyl value - 56.1 × 10^3); The hydroxyl value was determined using the phthalic anhydride method: based on the esterification reaction between phthalic anhydride and hydroxyl groups, excess phthalic anhydride was titrated with a standard sodium hydroxide solution, using phenolphthalein as an indicator. The hydroxyl value was calculated based on the volume of sodium hydroxide solution consumed. The specific procedure was as follows: approximately wg (calculated by dividing 561 by the estimated hydroxyl value, unit: g) of sample was weighed and placed in an Erlenmeyer flask, along with 25 mL of phthalic anhydride acylation reagent. The flask was shaken until the sample dissolved. An air condenser was attached to each Erlenmeyer flask, and the flask was placed in an oil bath at (105±2)℃ for 30 min. After heating, the apparatus was removed from the oil bath and cooled to room temperature. The condenser was rinsed with 30 mL of pyridine and then removed. Using phenolphthalein as an indicator, titration was performed with 0.5 mol / L potassium hydroxide solution. A blank test was also conducted under the same conditions. Let the volume of titrant consumed in the blank test be a (mL), the volume of titrant consumed in the sample solution be b (mL), and the sample size be w (g). The hydroxyl value was calculated by hydroxyl value = (ab) × 28.05 / w.

[0072] The specific test results are shown in Table 1.

[0073] Table 1

[0074] As shown in Table 1, the polyglycerol ether adduct basically maintains the branching degree and the ratio of primary and secondary hydroxyl groups of the original polyglycerol backbone.

[0075] Example 1 A grinding material composition is provided, the preparation steps of which include: (1) To prepare 100g of the grinding material composition, first, measure a specified volume (10ml) of deionized water into a beaker, add silica slurry, and adjust the mass concentration of colloidal silica in the system to 6%. Then, add 2.5g of polyglycerol compound pre-dissolved in deionized water in solution form and pre-stir at room temperature for 10 minutes. Next, add 0.3g of ammonia and 0.05g of 1,2-benzisothiazol-3-one in sequence, and mix using a homogenizer (trade name "TK Homomixer") at a speed of 3000 rpm for 30 minutes.

[0076] (2) After mixing, the resulting slurry was degassed under reduced pressure (approximately 10 kPa) for 15 minutes, and then left to stand at room temperature overnight for testing. At this time, the pH of the slurry at room temperature was 8.0.

[0077] Examples 2 to 8 and Comparative Examples 1 to 7 were prepared using similar steps to Example 1. The difference between Examples 2 to 8 and Comparative Examples 1 to 7 and Example 1 is that the polyglycerol compounds in the abrasive material compositions are different. For details, please refer to Table 2.

[0078] Table 2

[0079] Performance testing Performance testing: 1. Polishing performance test The final polishing test of the silicon oxide film was conducted using the CMP abrasive material composition (slurry) prepared in Example 1. An 8-inch diameter silicon wafer with a silicon oxide film (1.0 μm thick) formed on its surface by thermal oxidation was used as the workpiece. A single-sided polisher (trade name "EPO113") was used, and a polyurethane polishing pad (trade name "IC1000") was used.

[0080] The polishing conditions were set as follows: processing pressure of 2 psi (approximately 13.8 kPa); platform speed of 40 rpm. The wafer rotation speed was 35 rpm; the slurry supply rate was 150 mL / min; the polishing time was 60 seconds; and the slurry temperature was 25 ± 1℃. After polishing, the wafer was rinsed with pure water for 30 seconds, followed by spin drying. Polishing rate (RR) testing, surface roughness testing, scratch defect detection, and yield evaluation were performed as follows: 1.1 Polishing Rate (RR) Test: The thickness of the oxide film before and after polishing was measured using an ellipsometry, and the polishing rate (RR) was calculated according to the following formula (4): RR (nm / min) = (film thickness before polishing - film thickness after polishing) / polishing time (min). The polishing rate of the oxide film is calculated when using the obtained slurry.

[0081] 1.2. Surface roughness test: Surface roughness was measured using an atomic force microscope (AFM) over a 5 μm × 5 μm measurement area, and the arithmetic mean roughness Ra was calculated.

[0082] 1.3. Scratch Defect Detection: Multiple fields of view on the wafer surface were observed using a scanning electron microscope (SEM) (10 fields of view were selected within a 5 mm × 5 mm area). Linear defects with a length of more than 0.5 μm were counted by visual inspection or image analysis software. The number of scratches was then counted. The average number of scratches per wafer after slurry polishing was determined.

[0083] 1.4. Non-conforming rate assessment: This refers to the percentage of wafers (e.g., 8) that are polished under the same conditions and are deemed defective due to surface defects failing to meet the specified criteria. Defect assessment is determined by scanning electron microscopy (SEM) observation of at least 100 linear defects (scratches) with a length of 0.5 μm or more within a 5 mm × 5 mm observation area. If no defective wafers are detected when testing the slurry obtained from the above test examples, the non-conforming rate is 0%.

[0084] The performance test results are shown in Table 3.

[0085] Table 3

[0086] As shown in Table 3, the examples demonstrate that when linear polyglycerol is used directly, although the polishing rate is high due to the thinner adsorption layer formed on the surface of the abrasive particles, the reduction effect on surface roughness and scratches is inferior to that of polyglycerol derivatives containing alkyl groups. Specifically, by adding alkyl groups such as glycidyl ether derivatives, the adsorption layer becomes thicker and more uniform, alleviating localized loads. Therefore, although the polishing rate decreases, surface smoothness is improved, and the number of scratches is significantly reduced.

[0087] Compared with the examples, Comparative Example 1 did not add polyglycerol material, so the abrasive particles mainly made direct contact with the surface being polished, and failed to form an adsorption layer to alleviate local load concentration. As a result, the polishing rate, surface roughness, number of scratch defects, and defect rate were all worse than those of the examples.

[0088] Compared with Comparative Example 1, Comparative Example 2 showed improvement, but due to the low ratio of primary hydroxyl groups, the adsorption on the surface of the abrasive particles was insufficient, resulting in limited defect suppression effect.

[0089] Compared with Comparative Example 2, Comparative Example 3 also had the worst performance, showing that the non-uniformity of the adsorption state due to structural deviation was particularly significant.

[0090] Compared with Comparative Example 3, Comparative Example 4 was not as severe as Comparative Example 3, but it failed to achieve stable low-defect polishing.

[0091] Compared with Comparative Example 4, Comparative Example 5 had an increased adsorption layer thickness due to the introduction of alkyl groups, and the defect suppression effect was significantly improved compared with Comparative Example 2.

[0092] Compared with Comparative Example 5, Comparative Example 6 showed the worst results, indicating that the structural deviations of the skeleton itself still play a dominant role after the introduction of alkyl groups.

[0093] Although there was an improvement compared to Comparative Example 6, Comparative Example 7 still did not show sufficient defect suppression compared to Examples 1-3.

[0094] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. An abrasive material composition characterized in that, It includes polyglycerol compounds, abrasive materials, and additives: wherein the average degree of polymerization of the polyglycerol compounds is 6 to 40, the degree of branching of the polyglycerol compounds is less than 0.20, and the proportion of primary hydroxyl groups in the backbone of the polyglycerol compounds is more than 90% of the total number of hydroxyl groups.

2. The abrasive material composition according to claim 1, characterized in that, The average degree of polymerization of the polyglycerol compounds is 6 to 20.

3. The abrasive material composition according to claim 1, characterized in that, The abrasive material composition comprises, by weight percentage: Polyglycerol compounds 0.001~5%; Abrasive material 1~30%; Additives 0.1~0.5%; The rest is water.

4. The abrasive material composition according to claim 1, characterized in that, The polyglycerol compounds include polyglycerol derivatives, which are prepared by an ether addition reaction of polyglycerol with an average degree of polymerization of 4-40 and alkyl glycidyl ether or alkoxy glycidyl ether with 6-24 carbon atoms.

5. The abrasive material composition according to claim 1, characterized in that, The polyglycerol compounds include polyglycerol derivatives, which are formed by esterification of polyglycerol with an average degree of polymerization of 4 to 40 and fatty acids with 6 to 24 carbon atoms.

6. The abrasive material composition according to claim 1, characterized in that, The abrasive material includes at least one of colloidal silica, precipitated silica, fumed silica, alumina, cerium oxide, zirconium oxide, and silicon nitride; and / or, The abrasive material includes colloidal silica, and the average particle size of the colloidal silica is 0.01 to 0.1 μm.

7. A method for fabricating a semiconductor device, characterized in that, The process includes a chemical mechanical polishing step, wherein the abrasive material used in the chemical mechanical polishing step comprises the abrasive material composition according to any one of claims 1 to 6.

8. The method for fabricating a semiconductor device as described in claim 7, characterized in that, The chemical mechanical polishing includes a final fine polishing process for the oxide film applied in the shallow trench isolation structure formation process.

9. The method for fabricating a semiconductor device as described in claim 7, characterized in that, The chemical mechanical polishing includes an intermediate polishing process for the oxide film or an interlayer dielectric planarization process.

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