Preparation method of fine polishing liquid for glass wafer polishing

Abstract

The invention relates to the technical field of polishing material preparation, in particular to a preparation method of a fine polishing solution for glass wafer polishing, which comprises the following steps: (1) mixing rare earth carbonate and deionized water according to a mass ratio of 1: 1 to prepare slurry, and fully stirring; (2) on the basis of the weight of the rare earth carbonate, adding 5-10% of nano silicon dioxide sol with the central particle size of 10-50 nm into the slurry obtained in the step (1), heating to 90-100 DEG C, and carrying out heat preservation reaction for 2 hours; (3) carrying out wet ball milling on the slurry obtained in the step (2) after the high-temperature reaction, controlling the central particle size to be 0.5-1.0 mu m, and drying at 150 DEG C; (4) calcining the dried material obtained in the step (3) at 900-1000 DEG C for 18-24 hours; (5) mixing and fully stirring the calcined material obtained in the step (4) with deionized water, a dispersing agent, a chelating agent and a wetting agent, then carrying out wet ball milling to depolymerize, and controlling the central particle size to be 100-150nm to obtain polishing slurry; and (6) adding a lubricating thickener into the polishing slurry obtained in the step (5), stirring and dispersing at a high speed, and then adding a pH regulator to regulate the pH value of the slurry to 6-7, thereby obtaining the fine polishing liquid.

Description

Technical Field

[0001] This invention relates to the field of polishing material preparation technology, specifically to a method for preparing a fine polishing solution for polishing glass wafers. Background Technology

[0002] With the development of technology, glass wafers, as an emerging semiconductor material, have shown broad application prospects in many high-tech fields due to their unique physical and chemical properties and technological advantages. Their applications are no longer limited to traditional optics, but have expanded significantly into modern semiconductor manufacturing and related industries. In semiconductor manufacturing, glass wafers, due to their excellent insulation, thermal stability, and controllable physical properties, are expected to gradually replace or supplement silicon wafers in the future, becoming the mainstream or important substrate material for the manufacture of specific semiconductor devices. In the field of microelectromechanical systems (MEMS), glass wafers are commonly used as substrates or packaging carriers. Their dense properties provide effective protection for sensitive micromechanical components, preventing them from being corroded or physically damaged by environmental media during processing or use. Furthermore, glass wafers also play an important role in the fabrication of complementary metal-oxide-semiconductor (CMOS) image sensors, charge-coupled device (CCD) sensors, and high-performance microwave circuits. In particular, glass wafers have irreplaceable advantages in the fields of optics and laser devices. Its inherent high transparency, low dispersion, and good uniformity make it an ideal material for manufacturing high-precision lenses, optical windows, filters, and other optical components, contributing to higher-quality image acquisition and signal processing. Therefore, glass wafers are widely used in advanced optical imaging and detection systems such as high-definition cameras, LiDAR, and optical communication modules.

[0003] The fabrication of glass wafers is a complex and precise manufacturing process, generally involving multiple steps such as dicing, rough grinding, fine grinding, rough polishing, and fine polishing. The main purpose of the grinding step is to quickly remove the damaged layer and surface marks generated after dicing, achieving initial planarization of the wafer surface. The subsequent polishing step, especially chemical mechanical polishing (CMP), plays a decisive role in the surface quality of the final product. The polishing process is typically divided into two stages: rough polishing and fine polishing. The aim is to gradually eliminate micro-scratches, reduce surface roughness, and ultimately obtain a smooth, damage-free surface at the nanometer or even atomic level to meet the stringent requirements of high-end substrates or functional components.

[0004] Chemical mechanical polishing (CMP) slurries are core consumables in CMP processes, and their performance directly determines polishing efficiency, surface quality (such as roughness and smoothness), and defect control levels. To meet the ever-increasing demand for high-precision glass wafer processing, developing novel and efficient polishing slurries is crucial. Some related explorations have been undertaken in the prior art; for example, Chinese patent CN115011254 A discloses a CMP slurry for glass wafers and its preparation method. This technical solution aims to provide a high-precision polishing slurry that uses a single nano-oxide as the abrasive component, aiming to achieve glass wafer surface quality that meets high standards by optimizing the polishing slurry system.

[0005] While existing technologies such as CN115011254 A offer some solutions, the market still urgently needs chemical mechanical polishing slurries with higher polishing efficiency, better surface quality, wider process windows, and more controllable costs as the application fields of glass wafers continue to expand and the performance requirements of devices continue to increase. In particular, further technological innovation and improvement are needed to balance the contradiction between high material removal rates and low surface defects (such as scratches, pits, and haze), and to improve the surface cleanliness after polishing. Therefore, developing a chemical mechanical polishing slurry and its process that can more comprehensively meet the polishing requirements of advanced glass wafers has significant industrial application value. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for preparing a fine polishing solution for glass wafer polishing. To achieve the above objectives, the present invention provides the following technical solution: A method for preparing a fine polishing solution for glass wafer polishing, characterized by comprising the following steps: (1) Mix rare earth carbonates and deionized water at a mass ratio of 1:1 to form a slurry and stir thoroughly. (2) Based on the weight of the rare earth carbonate, add 5%-10% of nano silica sol with a central particle size of 10nm-50nm to the slurry obtained in step (1), heat to 90℃-100℃ and keep warm for 2 hours. (3) The slurry obtained after high-temperature reaction in step (2) is wet ball milled, and the central particle size is controlled at 0.5-1.0 μm, and then dried at 150℃; (4) Calcine the dried material obtained in step (3) at 900℃-1000℃ for 18-24 hours; (5) The calcined material obtained in step (4) is mixed with deionized water, dispersant, chelating agent and wetting agent and stirred thoroughly. Then, wet ball milling is performed to depolymerize the material and control the central particle size to 100-150nm to obtain polishing slurry. (6) Add a lubricating thickener to the polishing slurry obtained in step (5) and disperse it by high-speed stirring. Then add a pH adjuster to adjust the pH value of the slurry to 6-7 to obtain the fine polishing solution.

[0007] Preferably, the rare earth carbonate is one of praseodymium cerium carbonate and cerium carbonate.

[0008] Preferably, the dispersant is one or more of sodium hexametaphosphate, sodium polyacrylate, carboxylate dispersant AD6312, and sodium salt dispersant 5040.

[0009] Preferably, the chelating agent is one or more selected from HEDP-4Na, EDTA-2Na, sodium citrate, and sodium gluconate.

[0010] Preferably, the wetting agent is one or more of glycerol, sorbitol, Tween 60, and AEO-3.

[0011] Preferably, the lubricating thickener is one or more of magnesium aluminum silicate, nanocellulose, magnesium silicate, polyethylene glycol 2000, and polyethylene glycol 4000.

[0012] Preferably, the pH adjuster is one or more of malic acid, citric acid, lactic acid, and phytic acid.

[0013] A polishing solution for glass wafer polishing, characterized in that it is prepared by any one of claims 1 to 7, and its composition by weight percentage is: 10%-30% rare earth carbonate, 0.1%-0.3% chelating agent, 0.2%-0.5% dispersant, 0.1%-1% pH adjuster, 1%-3% wetting agent, 0.2%-0.5% lubricating thickener, and the balance being water.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. This work achieves a synergistic breakthrough in polishing efficiency and surface quality: Through innovative composite abrasive design and preparation process, it successfully solves the core contradiction in traditional fine polishing processes where high precision and high efficiency are difficult to achieve simultaneously. Specifically, it achieves an atomically smooth surface (surface roughness Sa < 0.3 nm) while maintaining a significantly high polishing rate of 1-2 μm / min, thereby greatly shortening processing time and effectively reducing production costs while ensuring ultimate surface precision.

[0015] 2. This noodle shop has innovated the preparation route of high-performance composite abrasives: through a unique "sol-gel encapsulation-high-temperature solid-phase reaction" process, nano-silica sol is used to condense into a three-dimensional network structure under heating conditions, which is then mutually encapsulated and nested with rare earth basic carbonate particles produced by hydrolysis, and finally transformed into composite oxides through high-temperature calcination. This method has successfully prepared a nano-cerium oxide-silicon composite abrasive with small grain size, high crystallinity, uniform particle morphology, and uniform particle size distribution. This abrasive possesses suitable mechanical strength and active chemical properties, providing a core material basis for efficient, uniform, and low-damage material removal.

[0016] 3. This invention forms a highly efficient synergistic system of chemical-mechanical action: This invention is not only an innovation in abrasives, but also achieves an optimized match between chemical and mechanical actions through a systematic slurry formulation design. The carefully selected chelating agents, dispersants, wetting agents, lubricating thickeners, and pH adjusters work synergistically with the composite abrasive to effectively promote the softening, hydrolysis, and product removal processes of the glass surface, stabilize the polishing interface, and reduce agglomeration and scratches, thereby jointly ensuring the achievement of the "fast and high-precision" polishing effect.

[0017] 4. The process of this invention has strong controllability and high product stability: The preparation method uses two key wet ball milling processes (one to control the precursor particle size and the second to control the final abrasive particle size), combined with a high-temperature calcination process, to ensure precise control and good reproducibility of the composite abrasive structure, morphology, and particle size. The resulting polishing slurry is stably dispersed and has uniform performance, which is beneficial for maintaining consistent polishing results in industrial production.

[0018] In summary, this invention has made systematic innovations in abrasive structure design, preparation process and polishing fluid formulation, and provides a solution that can significantly improve the overall efficiency (high efficiency, high precision and low cost) of glass wafer precision polishing process, which has important application value in the fields of precision optics and semiconductor manufacturing. Attached Figure Description

[0019] Figure 1 This is a surface roughness diagram of Embodiment 1 of the present invention.

[0020] Figure 2 This is a surface roughness diagram of Embodiment 2 of the present invention.

[0021] Figure 3 This is a surface roughness diagram of Embodiment 3 of the present invention.

[0022] Figure 4 This is a surface roughness diagram of Embodiment 4 of the present invention.

[0023] Figure 5 This is a surface roughness diagram of Embodiment 5 of the present invention.

[0024] Figure 6 This is a surface roughness diagram of Embodiment 6 of the present invention.

[0025] Figure 7 This is a surface roughness diagram of Embodiment 7 of the present invention.

[0026] Figure 8 This is a surface roughness diagram of Comparative Example 1 of the present invention.

[0027] Figure 9 This is a surface roughness diagram of Comparative Example 2 of the present invention. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all 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.

[0029] Example 1 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 50g of 10nm silica sol to (1) while stirring, heat the slurry to 90℃, and keep it warm for 2h while stirring. (3) The high-temperature slurry prepared in (2) was placed in a ball mill jar for wet crushing, and the central particle size was controlled to be 0.5 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 900℃ for 24 hours; (6) Weigh 200g of the roasted material in (5), add 784g of deionized water, 2g of sodium hexametaphosphate, 1g of HEDP-4Na and 10g of AEO-3 in sequence and stir thoroughly. After stirring evenly, add it to the ball mill jar for wet crushing and control the center particle size to 120nm. (7) The ball-milled polishing slurry was placed in a high-speed stirring and shearing machine, and 2g of magnesium aluminum silicate was added and stirred at high speed until the magnesium aluminum silicate was fully dispersed in the slurry. Then, 1g of malic acid was added to adjust the pH of the slurry to 6.7, and the fine polishing liquid sample 1 was obtained.

[0030] Example 2 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 100g of 50nm silica sol to (1) while stirring, heat the slurry to 100℃, and keep it warm for 2h while stirring. (3) The high-temperature slurry prepared in (2) was placed in a ball mill jar for wet crushing, and the central particle size was controlled to be 0.8 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 950℃ for 22 hours; (6) Weigh 200g of the roasted material in (5), add 783g of deionized water, 3g of sodium polyacrylate, 1g of EDTA-2Na and 10g of glycerol in sequence and stir thoroughly. After stirring evenly, add it to the ball mill jar for wet crushing and control the center particle size to 103nm. (7) The ball-milled polishing slurry was placed in a high-speed stirring and shearing machine, and 2g of nanocellulose was added and stirred at high speed until the nanocellulose was fully dispersed in the slurry. Then 1g of citric acid was added to adjust the pH of the slurry to 6.5, and the fine polishing liquid sample 2 was obtained.

[0031] Example 3 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 100g of 10nm silica sol to (1) while stirring, heat the slurry to 95℃, and keep it warm for 2 hours while stirring. (3) The high-temperature slurry prepared in (2) was placed in a ball mill jar for wet crushing, and the central particle size was controlled to be 1.0 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 1000℃ and the roasting time is 18h. (6) Weigh 200g of the roasted material in (5), add 750g of deionized water, 5g of AD6312, 3g of sodium gluconate and 30g of Tween 60 in sequence and stir thoroughly. After stirring evenly, add it to the ball mill jar for wet crushing and control the center particle size to 115nm. (7) The ball-milled polishing slurry was placed in a high-speed stirring shear machine, and 2g of polyethylene glycol 2000 was added and stirred at high speed until polyethylene glycol 2000 was fully dispersed in the slurry. Then 10g of phytic acid was added and the pH of the slurry was adjusted to 6.1 to obtain the fine polishing liquid sample 3.

[0032] Example 4 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 50g of 10nm silica sol to (1) while stirring, heat the slurry to 98℃, and keep it warm for 2h while stirring. (3) The high-temperature slurry prepared in (2) was placed in a ball mill jar for wet crushing, and the central particle size was controlled to be 1.0 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 980℃ for 20 hours; (6) Weigh 300g of the roasted material in (5), add 750g of deionized water, 5g of 5040, 3g of sodium citrate and 20g of Tween 60 in sequence and stir thoroughly. After stirring evenly, add it to the ball mill jar for wet crushing and control the center particle size to 110nm. (7) The ball-milled polishing slurry was placed in a high-speed stirring and shearing machine, and 5g of magnesium silicate was added and stirred at high speed until the magnesium silicate was fully dispersed in the slurry. Then 5g of lactic acid was added to adjust the pH of the slurry to 6.3, and the fine polishing liquid sample 4 was obtained.

[0033] Example 5 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 80g of 50nm silica sol to (1) while stirring, heat the slurry to 92℃, and keep it warm for 2h while stirring. (3) The high-temperature slurry prepared in (2) was placed in a ball mill jar for wet crushing, and the central particle size was controlled to be 0.6 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 980℃ for 20 hours; (6) Weigh 300g of the roasted material in (5), add 652g of deionized water, 3g of sodium hexametaphosphate, 5g of EDTA-2Na and 30g of glycerol in sequence and stir thoroughly. After stirring evenly, add it to a ball mill jar for wet crushing and control the center particle size to 106nm. (7) The ball-milled polishing slurry was placed in a high-speed stirring and shearing machine, and 5g of polyethylene glycol 4000 was added and stirred at high speed until the polyethylene glycol 4000 was fully dispersed in the slurry. Then, 5g of malic acid was added and the pH of the slurry was adjusted to 6.08 to obtain the fine polishing liquid sample 5.

[0034] Example 6 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 50g of 50nm silica sol to (1) while stirring, heat the slurry to 96℃, and keep it warm for 2h while stirring. (3) The high-temperature slurry prepared in (2) was placed in a ball mill jar for wet crushing, and the central particle size was controlled to be 0.7 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 900℃ for 24 hours; (6) Weigh 100g of the roasted material in (5), add 866g of deionized water, 2g of sodium hexametaphosphate, 2g of HEDP-4Na and 20g of sorbitol in sequence and stir thoroughly. After stirring evenly, add it to the ball mill jar for wet crushing and control the center particle size to 118nm. (7) The ball-milled polishing slurry was placed in a high-speed stirring shear machine, and 2g of polyethylene glycol 4000 was added and stirred at high speed until polyethylene glycol 4000 was fully dispersed in the slurry. Then 8g of phytic acid was added and the pH of the slurry was adjusted to 6.3 to obtain the fine polishing liquid sample 6.

[0035] Example 7 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 80g of 50nm silica sol to (1) while stirring, heat the slurry to 94℃, and keep it warm for 2h while stirring. (3) The high-temperature slurry prepared in (2) was placed in a ball mill jar for wet crushing, and the central particle size was controlled to be 0.65 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 960℃ for 24 hours; (6) Weigh 300g of the calcined material in (5), add 657g of deionized water, 5g of sodium polyacrylate, 3g of sodium citrate and 30g of AEO-3 in sequence and stir thoroughly. After stirring evenly, add it to the ball mill jar for wet crushing and control the center particle size to 103nm. (7) The ball-milled polishing slurry was placed in a high-speed stirring shear machine, and 2g of polyethylene glycol 2000 was added and stirred at high speed until the polyethylene glycol 2000 was fully dispersed in the slurry. Then, 3g of malic acid was added and the pH of the slurry was adjusted to 6.21 to obtain the fine polishing liquid sample 7.

[0036] Comparative Example 1 (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Heat the slurry to 96°C while stirring, and keep it at that temperature for 2 hours while stirring to obtain the precursor; (3) The precursor prepared in (2) was placed in a ball mill jar and wet crushed, and the central particle size was controlled to be 1.0 μm; (4) The qualified slurry (3) is directly placed in the drying oven and heated to 150℃ to dry the material; (5) The dried material is directly transferred into the muffle furnace, and the roasting temperature is set to 900℃ for 24 hours; (6) Weigh 300g of the calcined material in (5), add 657g of deionized water, 5g of sodium polyacrylate, 3g of HEDP-4Na and 30g of glycerol in sequence and stir thoroughly. After stirring evenly, add it to a ball mill jar for wet crushing and control the center particle size to 112nm. (7) The ball-milled polishing slurry was placed in a high-speed mixing and shearing machine, and 2g of polyethylene glycol 2000 was added and stirred at high speed until polyethylene glycol 2000 was fully dispersed in the slurry. Then, 3g of malic acid was added to adjust the pH of the slurry to 6.25, and control sample 1 was obtained.

[0037] Comparative Example 2 The specific steps for preparing a fine polishing solution for glass wafer polishing in this embodiment are as follows: (1) Take 1000g of cerium praseodymium carbonate and 1000g of deionized water, and stir well; (2) Based on the weight of cerium praseodymium carbonate, add 80g of 50nm silica sol to (1) while stirring, heat the slurry to 94℃, and keep it warm for 2h while stirring. (3) The slurry (2) after heat preservation is placed directly in the drying box and the temperature is set to 150℃ to heat and dry the material; (4) The dried material is transferred into a muffle furnace, and the roasting temperature is set to 960℃ for 24 hours; (5) Weigh 300g of the calcined material in (5), add 657g of deionized water, 5g of sodium polyacrylate, 3g of sodium citrate and 30g of AEO-3 in sequence and stir thoroughly. After stirring evenly, add it to the ball mill jar for wet crushing and control the center particle size to 104nm. (6) The ball-milled polishing slurry was placed in a high-speed mixing and shearing machine, and 2g of polyethylene glycol 2000 was added and stirred at high speed until the polyethylene glycol 2000 was fully dispersed in the slurry. Then, 3g of malic acid was added to adjust the pH of the slurry to 6.18, and control sample 2 was obtained.

[0038] The polishing slurry prepared in the example was mixed with 2000g of slurry with a solid content of 6% and polished into glass wafers according to the conditions in Table 1 below. The polishing rate and surface roughness were compared after polishing.

[0039] Table 1: Polishing conditions

[0040] Table 2 compares the polishing effects of the polishing solutions used in the embodiments and comparative examples of this invention on glass wafers.

[0041] like Figure 1-9 As shown, the surface roughness diagrams of Examples 1-7 and Comparative Examples 1-2 are shown; Table 2 shows the comparison of the polishing effects of the polishing solutions of Examples 1-7 and Comparative Examples 1-2 after polishing the glass wafers; The above polishing effects show that the glass wafer polishing solutions prepared in the examples have a fast polishing rate and low surface roughness after polishing, all of which can reach Sa < 0.2 nm and MRR of 1.5-2 μm / min.

[0042] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for preparing a fine polishing solution for glass wafer polishing, characterized in that, Includes the following steps: (1) Mix rare earth carbonates and deionized water at a mass ratio of 1:1 to form a slurry and stir thoroughly. (2) Based on the weight of the rare earth carbonate, add 5%-10% of nano silica sol with a central particle size of 10nm-50nm to the slurry obtained in step (1), heat to 90℃-100℃ and keep warm for 2 hours. (3) The slurry obtained after high-temperature reaction in step (2) is wet ball milled, and the central particle size is controlled at 0.5-1.0 μm, and then dried at 150℃; (4) Calcine the dried material obtained in step (3) at 900℃-1000℃ for 18-24 hours; (5) The calcined material obtained in step (4) is mixed with deionized water, dispersant, chelating agent and wetting agent and stirred thoroughly. Then, wet ball milling is performed to depolymerize the material and control the central particle size to 100-150nm to obtain polishing slurry. (6) Add a lubricating thickener to the polishing slurry obtained in step (5) and disperse it by high-speed stirring. Then add a pH adjuster to adjust the pH value of the slurry to 6-7 to obtain the fine polishing solution.

2. The preparation method according to claim 1, characterized in that: The rare earth carbonate is one of praseodymium cerium carbonate and cerium carbonate.

3. The preparation method according to claim 1, characterized in that: The dispersant is one or more of sodium hexametaphosphate, sodium polyacrylate, carboxylate dispersant AD6312, and sodium salt dispersant 5040.

4. The preparation method according to claim 1, characterized in that: The chelating agent is one or more of HEDP-4Na, EDTA-2Na, sodium citrate, and sodium gluconate.

5. The preparation method according to claim 1, characterized in that: The wetting agent is one or more of glycerol, sorbitol, Tween 60 and AEO-3.

6. The preparation method according to claim 1, characterized in that: The lubricating thickener is one or more of magnesium aluminum silicate, nanocellulose, magnesium silicate, polyethylene glycol 2000, and polyethylene glycol 4000.

7. The preparation method according to claim 1, characterized in that: The pH adjuster is one or more of malic acid, citric acid, lactic acid, and phytic acid.

8. A polishing solution for polishing glass wafers, characterized in that, The preparation method according to any one of claims 1 to 7 is used to prepare the following product, which is composed of the following components by weight percentage: 10%-30% rare earth carbonate, 0.1%-0.3% chelating agent, 0.2%-0.5% dispersant, 0.1%-1% pH adjuster, 1%-3% wetting agent, 0.2%-0.5% lubricating thickener, and the balance being water.

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