A doped yttria flake powder, its preparation method and use

Abstract

This invention relates to a doped yttrium oxide flake powder, its preparation method, and its applications. The method uses 0.2-0.4 M Y(NO₃)₂. 3 ) 3 ·6H 2 O solution as Y 3+ Source, then add MgCl to the solution 2 and Al(NO 3 ) 3 ·9H 2 O was used as a dopant. After adjusting the pH of the mixed solution to 8-10, a hydrothermal reaction was carried out at 170-200°C for 9-15 hours to achieve uniform distribution of the dopant in the yttrium oxide lattice. Finally, the powder was calcined at 600-700°C for 3-5 hours to improve the structural stability and properties of the material. The synthesized doped yttrium oxide powder had a plate-like morphology with a particle size between 5-25 micrometers, and the final product composition included Y. 2 O 3 MgAl 2 O 4 And Y-Al-O compounds. Compared with traditional physical doping methods, the preparation method of this invention not only achieves a more uniform doping effect, but also shows significant advantages in terms of energy consumption, cost, and particle size control. The doped yttrium oxide obtained by this method has performance superior to or equivalent to high-purity yttrium oxide, providing a new avenue for the further application and development of yttrium oxide.

Description

A doped yttrium oxide flake powder, its preparation method and application Technical Field

[0001] This invention belongs to the field of yttrium oxide powder and its preparation technology, and relates to a doped yttrium oxide powder, its preparation method and application, and in particular to a method for synthesizing Y2O3 powder doped with magnesium aluminum spinel (MgAl2O4) and Y-Al-O compound in a single hydrothermal synthesis to enhance its performance. Background Technology

[0002] Yttrium oxide (Y₂O₃), as an important rare earth oxide, is widely used in many high-tech fields due to its excellent physical and chemical stability. Especially in semiconductor manufacturing, high-purity yttrium oxide is used as a protective coating material for the inner walls of plasma etching equipment due to its good resistance to plasma erosion. However, the preparation cost of high-purity yttrium oxide materials is high, and its resistance to plasma erosion still needs further improvement to avoid unnecessary contamination of wafers during semiconductor wafer processing. Therefore, doping is necessary to further enhance the performance of pure yttrium oxide.

[0003] Traditionally, the preparation of doped yttrium oxide has relied on physical doping methods, such as ball milling. These methods suffer from uneven dopant distribution in practical applications. Inhomogeneous doping leads to unstable material properties, limiting its effectiveness in certain applications. Furthermore, these physical methods often require high energy consumption and more complex post-processing.

[0004] Therefore, it is essential to design an efficient preparation method in order to obtain doped yttrium oxide powder with better performance.

[0005] It should be noted that the information disclosed in this background section is intended only to enhance the understanding of the overall background of the present invention, and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a doped yttrium oxide flake powder, its preparation method, and its applications. The invention innovatively employs a hydrothermal synthesis process to prepare the doped yttrium oxide powder. This method involves using magnesium aluminum spinel (MgAl2O4) and γ-Al-O compounds as dopants under hydrothermal conditions to uniformly introduce these dopants into the yttrium oxide lattice. Compared with traditional physical doping methods, the preparation method employed in this invention can achieve a uniform distribution of dopants at the molecular level. This uniform doping not only improves the overall performance of the material, especially its resistance to plasma erosion, but also enhances its thermal stability and mechanical strength.

[0007] To achieve the above objectives, this application adopts the following technical solution:

[0008] In a first aspect, this application provides a doped yttrium oxide flake powder comprising the following components in the following mass percentages: Y2O3: 55~65 wt.%; MgAl2O4: 10~20 wt.%; and Y-Al-O compound: 15~35 wt.%; the powder has a flake-like morphology with a particle size between 5 and 25 micrometers.

[0009] Furthermore, the Y-Al-O compound includes Al2Y4O9, YAlO3, and Y3Al5O. 12 At least one of them.

[0010] Secondly, this application provides a method for preparing the doped yttrium oxide flake powder described in the first aspect above, comprising the following steps:

[0011] 1) Solution preparation: First, prepare a 0.2-0.4M Y(NO3)3·6H2O solution as Y 3+ The source;

[0012] 2) Dopant addition: Subsequently, MgCl2 and Al(NO3)3·9H2O were added to the solution obtained in step 1) according to the mass ratio. The amount of dopant added determines the content of the generated magnesium aluminum spinel (MgAl2O4) and γ-Al-O compound in the doped yttrium oxide flake powder;

[0013] 3) pH adjustment: The pH of the above solution was adjusted to 8-10 by titration with NH3·H2O solution to prepare for the hydrothermal reaction;

[0014] 4) Hydrothermal reaction preparation: Transfer the pH-adjusted solution to a PTFE liner equipped with a magnetic stirrer to prepare for the hydrothermal reaction. The magnetic stirring device in the hydrothermal reactor ensures uniform mixing during the reaction.

[0015] 5) Hydrothermal reaction: The solution is reacted in a hydrothermal reactor at 170℃-200℃ for 9-15 hours;

[0016] 6) Washing and Drying: After the hydrothermal reaction is complete, the solution is cooled to room temperature, and the powder is collected by filtration. The powder is then washed and dried to ensure the removal of impurities and the purity of the powder.

[0017] 7) Calcination treatment: Finally, the dried powder is ground to achieve uniform particle size; then it is calcined at 600℃-700℃ for 3-5 hours to further improve the structural stability and performance of the material.

[0018] Furthermore, this application also provides the application of the doped yttrium oxide flake powder of the first aspect above in a plasma etching apparatus.

[0019] The beneficial effects of this application are:

[0020] The doped yttrium oxide flake powder obtained by the method of this invention exhibits excellent physical and chemical properties, such as a high melting point, good electrical insulation, and superior thermal stability. In particular, it demonstrates better resistance to plasma erosion compared to pure yttrium oxide powder, thus effectively preventing unnecessary contamination of the wafer during semiconductor wafer fabrication. Furthermore, compared to traditional physical doping methods, the hydrothermal synthesis method of this invention not only achieves more uniform doping but also features lower energy consumption and better particle size control during the reaction process. This provides a more economical and efficient new approach for the preparation of high-performance yttrium oxide materials, overcoming the limitations of traditional physical doping methods and opening up new possibilities for the application of yttrium oxide and related materials. Attached Figure Description

[0021] Figure 1 shows a process flow diagram of a method for preparing doped yttrium oxide flake powder by hydrothermal synthesis according to an embodiment of this application;

[0022] Figure 2 shows a SEM image of doped yttrium oxide flake powder magnified 3000 times according to Embodiment 1 of this application;

[0023] Figure 3 shows a SEM image of doped yttrium oxide flake powder magnified 5000 times according to Embodiment 1 of this application;

[0024] Figure 4 shows the XRD pattern of the prepared doped yttrium oxide flake powder according to Example 1 of this application. Detailed Implementation Methods

[0025] The technical features and advantages of this application will be described in more detail below with reference to the embodiments and accompanying drawings, so that the advantages and features of this application can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the scope of protection of this invention.

[0026] The embodiments of this application first provide a doped yttrium oxide flake powder, comprising the following components in the following mass percentages: Y₂O₃: 55~65 wt.%; MgAl₂O₄: 10~20 wt.%; and Y-Al-O compound: 15~35 wt.%; wherein the above-mentioned Y-Al-O compound includes Al₂Y₄O₉, YAlO₃, and Y₃Al₅O₂. 12At least one of the following. The powder has a flake-like morphology with a particle size between 5 and 25 micrometers. Compared with pure yttrium oxide powder, the doped yttrium oxide powder of this application embodiment has better physical and chemical properties, especially better resistance to plasma erosion, and can be used in plasma etching equipment to effectively avoid unnecessary contamination of the wafer.

[0027] Secondly, embodiments of this application also provide a method for preparing the above-mentioned doped yttrium oxide flake powder by hydrothermal synthesis, comprising the following steps:

[0028] 1. Solution Preparation: First, prepare a 0.2-0.4M solution of Y(NO3)3·6H2O under laboratory conditions. This solution will be used as the Y... 3+ The source ensures a sufficient supply of Y element during the synthesis of yttrium oxide;

[0029] 2. Dopant Addition: MgCl2 and Al(NO3)3·9H2O are added to the above solution according to a predetermined mass ratio. The amount of dopant added determines the content of the generated magnesium aluminum spinel (MgAl2O4) and Y-Al-O compound in the yttrium oxide (Y2O3) flake powder. The specific amount and ratio of MgCl2 and Al(NO3)3·9H2O added depend on the performance requirements of the doped powder in the final application scenario;

[0030] 3. pH adjustment: The pH of the solution was adjusted to 8-10 by titration with NH3·H2O solution to prepare for the hydrothermal reaction;

[0031] 4. Hydrothermal Reaction Preparation: Transfer the pH-adjusted solution to a PTFE liner equipped with a magnetic stirrer, ready for the hydrothermal reaction. To ensure a stable hydrothermal reaction, the solution volume transferred should be 50%-70% of the total volume of the PTFE liner.

[0032] 5. Hydrothermal reaction: The inner liner is placed in a hydrothermal reactor and subjected to a hydrothermal reaction at 170-200°C for 9-15 hours. This process is a key step in the synthesis of doped yttrium oxide powder in this embodiment of the application. In this step, the dopant is uniformly distributed into the crystal structure of yttrium oxide, thereby achieving doping at the molecular level.

[0033] 6. Separation and Washing: After the reaction is complete, allow the solution to cool naturally to room temperature, and then collect the powder by filtration. The collected powder is first ultrasonically washed with ultrapure water at least three times, 20 minutes each time, followed by ultrasonically washed with anhydrous ethanol at least three times, 20 minutes each time, to remove possible impurities and ensure the purity of the powder;

[0034] 7. Drying treatment: Dry the washed powder at 90°C for 7-12 hours to remove residual moisture;

[0035] 8. Calcination treatment: The dried powder is ground to achieve a uniform particle size, and then calcined at 600°C-700°C for 3-5 hours to further improve the structural stability and performance of the material.

[0036] 9. Property Analysis: Finally, the morphology and composition of the obtained powder were evaluated using techniques such as scanning electron microscopy (SEM) and X-ray diffraction (XRD).

[0037] Through the above steps, this embodiment successfully prepared doped yttrium oxide flake powder with excellent performance. This method not only achieves uniform distribution of the dopant in yttrium oxide but also provides a high-efficiency and low-cost preparation method. The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0038] In the following examples, all raw materials and reagents used were commercially available or self-made. The reaction and testing equipment used were as follows: (1) The hydrothermal reactor was a miniature magnetic stirring reactor (model CQ-PSK-500ML) manufactured by Nanjing Zhengxin Instruments; (2) The scanning electron microscope used for microscopic morphology was an Oxford Instruments EVO 10; (3) The equipment used for phase analysis was a Bruker D8, with a scanning range of 5°-90°, a scanning step size of 0.02°, and a step duration of 0.3s. Example 1

[0039] In this embodiment, 200 mL of a 0.3 M Y(NO3)3·6H2O solution was first prepared. Then, 1.23 g of MgCl2 and 14.0 g of Al(NO3)3·9H2O were added to this solution. The pH of the solution was then adjusted to 9 using NH3·H2O solution. Subsequently, a hydrothermal reaction was carried out at 180°C for 12 hours. After the reaction was complete, the resulting powder was collected, washed, and dried. Finally, the powder was calcined at 600°C for 3 hours. Referring to Figures 2-3, scanning electron microscopy (SEM) analysis confirmed that the obtained powder had a flake-like morphology with an average particle size of 10-20 micrometers. Please refer to Figure 4. XRD analysis shows that the powder composition includes approximately 65 wt.% Y₂O₃, 20 wt.% MgAl₂O₄, and 15 wt.% Y-Al-O compounds (including Al₂Y₄O₉, YAlO₃, and Y₃Al₅O₄). 12 Example 2

[0040] In this embodiment, a 200 mL 0.25 M Y(NO3)3·6H2O solution was first prepared. Then, 0.5 g of MgCl2 and 12.3 g of Al(NO3)3·9H2O were added to this solution. The pH of the solution was adjusted to 8.5 using NH3·H2O solution. A hydrothermal reaction was carried out at 180°C for 10 hours. After the reaction, the resulting powder was collected, washed, and dried. Subsequently, the powder was calcined at 600°C for 4 hours. SEM analysis showed that the obtained powder had a flake-like morphology with an average particle size of 15-25 μm. XRD analysis confirmed that the powder composition was 55 wt.% Y2O3, 10 wt.% MgAl2O4, and 35 wt.% Y-Al-O compounds (including Al2Y4O9, YAlO3, and Y3Al5O). 12 Example 3

[0041] In this embodiment, a 200 mL 0.2 M Y(NO3)3·6H2O solution was first prepared. Then, 0.85 g% MgCl2 and 10.67 g Al(NO3)3·9H2O were added to this solution. Subsequently, the pH of the solution was adjusted to 10 using NH3·H2O solution. The hydrothermal reaction was carried out in a hydrothermal reactor at 200°C for 9 hours. After the reaction was completed, the powder was collected, washed, and dried. Finally, the powder was calcined at 600°C for 5 hours. SEM analysis showed that the obtained powder had a flake-like morphology with an average particle size of 5-15 micrometers. XRD analysis showed that the powder composition included approximately 60 wt.% Y2O3, 20 wt.% MgAl2O4, and 10 wt.% Y-Al-O compounds (including Al2Y4O9, YAlO3, and Y3Al5O). 12 ).

[0042] In the applicant's actual use, the doped yttrium oxide powder of the above embodiments exhibits superior performance in terms of both mechanical strength and thermal stability compared to high-purity yttrium oxide powder.

[0043] In particular, in order to examine the erosion resistance of the doped yttrium oxide powder in the embodiments of this application, the applicant prepared the doped yttrium oxide powder obtained in the above embodiments 1-3 into block samples, conducted etching experiments, and compared them with samples prepared from pure yttrium oxide. The doped yttrium oxide sample in this embodiment showed better erosion resistance.

[0044] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made based on the content of this specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A yttrium oxide-doped flake powder, characterized in that, The powder was prepared by the following method: 1) Solution preparation: Prepare a 0.2-0.4 M Y(NO3)3·6H2O solution; 2) Dopant addition: Add MgCl2 and Al(NO3)3·9H2O to the solution; 3) pH adjustment: Adjust the pH to 8-10 using NH3·H2O; 4) Hydrothermal reaction: React at 170-200℃ for 9-15 hours; 5) Washing and drying; 6) Calcination: Calcine at 600-700℃ for 3-5 hours. The chemical composition of the obtained powder, by mass percentage, includes: Y2O3: 55-65 wt.%; MgAl2O4: 10-20 wt.%; Y-Al-O compound: 15-35 wt.%; and has a flake-like morphology of 5-25 μm.

2. The doped yttrium oxide flake powder according to claim 1, characterized in that, The Y-Al-O compounds include Al2Y4O9, YAlO3, and Y3Al5O. 12 At least one of them.

3. The doped yttrium oxide flake powder according to claim 1, characterized in that, Before step 4), there is also a hydrothermal reaction preparation step: transfer the solution after adjusting the pH value in step 3) to the polytetrafluoroethylene liner equipped with a magnetic stirrer, and the amount of solution transferred is 50%-70% of the total volume of the polytetrafluoroethylene liner.

4. The doped yttrium oxide flake powder according to claim 1, characterized in that, The washing step in step 5) specifically includes: first, ultrasonically washing the collected powder with ultrapure water at least three times; then, ultrasonically washing it with anhydrous ethanol at least three times.

5. The doped yttrium oxide flake powder according to claim 1, characterized in that, The drying step in step 5) specifically includes drying the powder obtained in step 5) at 90°C for 7-12 hours.

6. The doped yttrium oxide flake powder according to claim 1, characterized in that, The calcination step in step 6) specifically includes calcining at 600℃-700℃ for 3-5 hours.

7. The application of doped yttrium oxide flake powder according to any one of claims 1-6 in a plasma etching apparatus.

Images