Method for recovering yttrium oxide coating on semiconductor equipment part

Abstract

The invention provides a method for recovering an yttrium oxide coating on a semiconductor equipment part, which comprises the following steps: soaking the part in an acidic etching solution, dissolving the yttrium oxide coating to form a to-be-treated solution, the acidic etching solution containing weak acid; removing insoluble impurities and metal cations except yttrium in the liquid to be treated; impurity anions, a metal corrosion inhibitor and other impurities in the to-be-treated liquid are removed in an electrodialysis mode, and yttrium ion-containing treatment liquid is obtained; and adjusting the pH value of the obtained yttrium ion-containing treatment liquid to obtain yttrium hydroxide precipitate, and filtering, drying and calcining the yttrium hydroxide precipitate to obtain a yttrium oxide product. According to the recovery method, yttrium oxide can be recovered under the condition that the metal substrate is not damaged, and the obtained yttrium oxide product can be used as a reaction source material when yttrium oxide is coated on the surfaces of semiconductor equipment parts by using a vapor deposition method subsequently.

Description

Technical Field

[0001] The present invention relates to the field of rare earth material recycling, and particularly to a method for recycling yttrium oxide coatings on semiconductor device components. Background Art

[0002] In the semiconductor field, corrosion resistance is one of the crucial characteristics for components in the process chambers of semiconductor devices used in various corrosive environments. For example, plasma etching equipment typically uses highly corrosive process gases such as CF 4 , Cl 2 etc. To better protect the components inside the plasma chamber and extend the service life of related components in the plasma environment, researchers use rare earth coatings such as high-purity yttrium oxide, yttrium fluoride, and yttrium oxyfluoride to protect the surfaces of plasma etching equipment components, which can greatly improve their corrosion resistance. However, as the usage time of these components reaches a certain on-machine usage time, inevitable damage problems such as wear or cracking of the yttrium oxide coating occur, resulting in loss of use value. The common practices are: First, scrapping the used components; Second, mechanically grinding off the yttrium oxide coating on their surfaces and reusing the substrate.

[0003] Rare earths such as yttrium are precious strategic resources with low production and high prices, and are widely used in high-tech fields and cutting-edge technology industries. Scrapping or simply mechanically removing the yttrium oxide coating will cause significant waste of resources. If the high-purity yttrium oxide coating on semiconductor device components can be effectively recycled, it will bring great economic and social value. Summary of the Invention

[0004] The object of the present invention is to provide a method for recycling the yttrium oxide coating on the surface of semiconductor components, which can recycle the yttrium oxide coating on the surface of semiconductor device components, and at the same time ensure that the recovered yttrium oxide material has a very high purity and can be used as a reaction source material for subsequent coating of yttrium oxide on the surface of semiconductor device components by chemical vapor deposition.

[0005] To achieve the above object, the present invention provides a method for recycling the yttrium oxide coating on semiconductor device components, the components including a metal substrate and a yttrium oxide coating provided on the metal substrate, comprising the following steps:

[0006] Etching step: Immerse the components in an acidic etching solution to dissolve the yttrium oxide coating to form a solution to be treated, the acidic etching solution being a weak acid solution, and the metal substrate substantially maintaining its original surface morphology after etching is completed;

[0007] Impurity removal step: Remove the impurity components in the liquid to be treated to obtain a yttrium ion-containing treatment liquid, where the impurity components are at least one of insoluble impurities, metal cations other than yttrium, impurity anions, or organic molecules;

[0008] Recovery step: Adjust the pH value of the yttrium ion-containing treatment liquid to obtain yttrium hydroxide precipitate. After filtration, drying, and calcination operations, yttrium oxide product is obtained.

[0009] Optionally, when removing the impurity anions and / or the organic molecules, electrodialysis method is used for treatment.

[0010] Optionally, the electrolyte in the electrodialysis cell when using the electrodialysis method is at least one of sulfuric acid or nitric acid.

[0011] Optionally, the weak acid includes one or more of tartaric acid, lactic acid, malic acid, citric acid, ascorbic acid, gluconic acid, or aspartic acid.

[0012] Optionally, the acidic etching solution further contains a metal corrosion inhibitor, and the metal corrosion inhibitor includes one or more of benzimidazole, methylbenzimidazole, 8-hydroxyquinoline, catechol, sorbitol, maltitol, mannitol, or glucose.

[0013] Optionally, the use concentration of the acidic etching solution is 10% - 100%, and the use temperature of the acidic etching solution is 20 - 50 °C.

[0014] Optionally, the method further includes the step of using an organic solvent to remove the organic polymer contaminants on the surface of the parts.

[0015] Optionally, the insoluble impurities include one or more of aluminum fluoride or yttrium fluoride, and the metal cations other than yttrium include one or more of copper, iron, or aluminum.

[0016] Optionally, ion exchange treatment is used to remove the metal cations other than yttrium.

[0017] Optionally, before the ion exchange treatment, it further includes the step of adjusting the pH value of the liquid to be treated to 5.5 - 6.5.

[0018] Optionally, when using the electrodialysis method to remove the impurity anions and / or the organic molecules, the temperature of the electrodialysis system does not exceed 38 °C, and the current during electrodialysis does not exceed 100 A.

[0019] Optionally, ammonia water is used to adjust the pH of the obtained yttrium ion-containing treatment liquid, and the adjusted pH value is between 8.5 - 9.5 to obtain the yttrium hydroxide precipitate.

[0020] Optionally, it further includes the steps of centrifuging and separating the yttrium hydroxide precipitate, drying it, and calcining it to obtain a yttrium oxide product.

[0021] Optionally, the drying temperature for drying is 60 - 100 °C.

[0022] Optionally, the calcination temperature for calcining is 700 - 900 °C, and the calcination time is 1 - 5 hours.

[0023] Optionally, the material of the metal substrate is aluminum or aluminum alloy.

[0024] Optionally, an anodic aluminum oxide layer is further provided on the metal substrate.

[0025] Optionally, the semiconductor device component is at least one of a gas shower head, a mounting substrate, a device board, a gas pipeline, a gas nozzle, a dielectric window, or a lining.

[0026] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects:

[0027] 1. The recovery method of the high-purity yttrium oxide coating on the semiconductor device component of the present invention has a simple process. The acidic etching solution only reacts with yttrium oxide, effectively avoiding damage to the substrate, and the substrate can also be reused.

[0028] 2. The recovery method of the high-purity yttrium oxide coating on the semiconductor device component of the present invention is green and environmentally friendly. Combining ion exchange technology and electrodialysis technology can effectively remove anionic and cationic impurities and metal corrosion inhibitors introduced during the use and recovery of the components, and only recover high-purity yttrium oxide, which has great economic value and social value. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solution of the present invention, the drawings required for description will be briefly introduced below. Obviously, the drawings in the following description are an embodiment of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts:

[0030] Figure 1 It is a schematic structural diagram of a semiconductor device component of the present invention;

[0031] Figure 2 It is a schematic flow diagram of a yttrium oxide recovery method on a semiconductor device component provided by the present invention;

[0032] Figure 3 It is a schematic flow diagram of Embodiment 1 of the present invention;

[0033] Figure 4 It is a schematic diagram of the principle of electrodialysis for recovering yttrium salt used in the present invention;

[0034] Figure 5 Schematic diagram of the surface of the overall components of the present invention;

[0035] Figure 6 Schematic diagram of the surface of the components of the present invention under an optical microscope. Detailed implementation manners

[0036] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than 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 making creative efforts shall fall within the protection scope of the present invention.

[0037] It should be understood that when used in this specification and the appended claims, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0038] It should also be understood that the terms used in the description of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the description of the present application and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0039] It should be further understood that the term "and / or" used in the description of the present application and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0040] In addition, in the description of the present application, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0041] Please refer to Figure 1, which is a schematic diagram of the structure of a semiconductor device component. The component includes: a substrate 100 made of a metal material, and a yttrium oxide coating 120 coated on the substrate 100. Specifically, the substrate 100 is made of aluminum or an aluminum alloy material, and an anodic aluminum oxide layer 110 is further provided on the surface of the substrate 100. The anodic aluminum oxide layer 119 can be provided on the front or back of the substrate 100. The yttrium oxide coating 120 is coated on the substrate 100 by a deposition method. The deposition method can be one or more of chemical vapor deposition (CVD), physical vapor deposition (PVD), atomic layer deposition (ALD), or plasma spraying (PS), but the present invention is not limited thereto.

[0042] The semiconductor device component can be a component in a capacitively coupled plasma processing device, including: at least one of a gas showerhead, a mounting substrate for mounting the gas showerhead, a device plate for supporting an electrostatic chuck, and a gas pipeline; or it can be a component in an inductively coupled plasma processing device, including at least one of a gas nozzle, a liner disposed around the reaction chamber, a device plate for supporting an electrostatic chuck, a gas pipeline, and a dielectric window.

[0043] Existing yttrium oxide recovery methods usually use strong acid solutions to extract parts or fluorescent powders, such as strong acid solutions like sulfuric acid, hydrochloric acid, or nitric acid. Since the substrate of the above semiconductor device component is made of aluminum or an aluminum alloy material, when it is necessary to recover the yttrium oxide coating coated on the surface of the component, using traditional strong acid solutions will corrode the aluminum or aluminum alloy substrate, which is not conducive to the subsequent use of the component and the recovery of high-purity yttrium oxide. Based on this, the present invention provides a method for recovering a high-purity yttrium oxide coating on a semiconductor device component, which is as follows.

[0044] Please refer to Figure 2 , which is a method for recovering a high-purity yttrium oxide coating on a semiconductor device component provided by the present invention, including the following steps:

[0045] Step 201, etching step: Immerse the component in an acidic etching solution to dissolve the yttrium oxide coating to form a solution to be processed. The acidic etching solution contains a weak acid.

[0046] Specifically, in order to prevent the acidic etching solution from corroding the metal substrate, the main component of the acidic etching solution is a weak acid that does not react with aluminum or aluminum alloy. The weak acid includes one or more of tartaric acid, lactic acid, malic acid, citric acid, ascorbic acid, gluconic acid, or aspartic acid. Specifically, the weak acid here refers to the definition of the corrosion strength of aluminum or an aluminum substrate. The etching rate of the weak acid solution on the aluminum substrate is less than 0.006 μm / h, while the etching rate of the traditional strong acid etching solution on the aluminum substrate is greater than 9.8 μm / h, which is not conducive to the subsequent use of the components. In addition, in order to further prevent the acidic etching solution from corroding the aluminum or aluminum alloy substrate and the anodic aluminum oxide layer, the acidic etching solution also contains a metal corrosion inhibitor, which includes one or more of benzimidazole, methylbenzimidazole, 8-hydroxyquinoline, catechol, sorbitol, maltitol, mannitol, or glucose.

[0047] Step 202, impurity removal step: Remove the impurity components in the liquid to be treated to obtain a yttrium ion-containing treatment liquid. The impurity components are at least one of insoluble impurities, metal cations other than yttrium, impurity anions, or organic molecules.

[0048] Specifically, the liquid to be treated obtained in step 201 contains at least one of insoluble impurities, metal cations other than yttrium, impurity anions, or organic molecules. In this step, first, the insoluble impurities are removed by filtration, then the metal cations other than yttrium are removed by ion exchange treatment, and then the impurity anions and organic molecules are removed by electrodialysis to obtain a high-purity yttrium ion-containing treatment liquid. Impurity anions cannot be removed by ion exchange treatment. Therefore, in this step, the anions, organic molecules and other impurities, that is, the anion impurities and metal corrosion inhibitors contained in the acidic etching solution used in step 201, are removed by electrodialysis to avoid affecting the purity of the subsequent yttrium oxide product.

[0049] Step 203, recovery step: Adjust the pH value of the yttrium ion-containing treatment liquid to obtain a yttrium hydroxide precipitate. After filtration, drying, and calcination operations, a yttrium oxide product is obtained.

[0050] Specifically, the pH of the yttrium ion-containing treatment liquid is adjusted with an alkaline solution to obtain a yttrium hydroxide precipitate. After the yttrium hydroxide precipitate is filtered out, it is dried and calcined to obtain a yttrium oxide product.

[0051] Optionally, before performing step 201, it also includes the step of using an organic solvent to remove the organic polymer contaminants on the surface of the component.

[0052] Example 1:

[0053] This embodiment provides a method for recycling high-purity yttrium oxide coatings on semiconductor device components. For specific steps, please refer to Figure 3 , which includes the following steps:

[0054] Step S10: Use solvents such as high-purity isopropyl alcohol or high-purity acetone to clean the used and scrapped components with yttrium oxide coatings to remove contaminants such as organic polymers attached to their surfaces.

[0055] Specifically, due to the commonly used hydrofluorocarbon gas (C X H Y F Z ) or fluorocarbon gas (C X F Y ) in semiconductor processes, organic polymers will be generated and deposited on semiconductor device components during the process. These organic polymers are not conducive to the subsequent recycling of yttrium oxide materials. Therefore, they are first removed by organic solvents.

[0056] The recycling method is carried out in a cleanroom. Since semiconductor devices have high requirements for cleanliness, when recycling yttrium oxide, in order to ensure the cleanliness requirements, it needs to be carried out under dust-free conditions. Optionally, the cleanroom is of class 100.

[0057] In some embodiments, when cleaning the organic polymer, the temperature of the organic solvent is at room temperature. To enhance the cleaning effect, ultrasonic waves are used as an aid during cleaning until the organic polymer is completely removed. Optionally, the frequency of the ultrasonic waves is 40 - 120 KHz, and the energy density is 1 - 10 W / inch 2 .

[0058] Step S20: Further immerse the cleaned components in an acidic etching solution to completely etch and dissolve the yttrium oxide coating, forming a solution to be processed.

[0059] Specifically, to prevent the acidic etching solution from corroding the metal substrate, the main component of the acidic etching solution is a weak acid that does not react with aluminum or aluminum alloy. The weak acid includes one or more of tartaric acid, lactic acid, malic acid, citric acid, ascorbic acid, gluconic acid, or aspartic acid. In addition, to further prevent the acidic etching solution from corroding the aluminum or aluminum alloy substrate and the anodic aluminum oxide layer, the acidic etching solution also contains a metal corrosion inhibitor, which includes one or more of benzimidazole, methylbenzimidazole, 8-hydroxyquinoline, catechol, sorbitol, maltitol, mannitol, or glucose.

[0060] In some embodiments, the pH value of the acidic etching solution is 3.5 - 5.5. The operating temperature of the acidic etching solution is 20 - 50°C, and the operating concentration of the acidic etching solution is 10v% - 100v%. To increase the etching uniformity and etching rate, when performing this step, the containing tank holding the acidic etching solution can be aerated and slightly shaken.

[0061] After the etching is completed, the concentration of yttrium ions in the liquid to be treated is 1 - 10 g / L.

[0062] Yttrium oxide has stable chemical properties and is insoluble in water and alkaline solutions, but it is easily soluble in acid solutions. The reaction equation is as follows:

[0063] Y 2 O 3 +6H + →2Y 3+ +3H 2 O

[0064] Step S30: Take out the component substrate and use a filter to remove a small amount of insoluble impurities in the liquid to be treated, such as particulate pollutants like aluminum fluoride and yttrium fluoride.

[0065] Some semiconductor equipment components, such as gas showerheads, during use, when encountering fluorine-containing process gases such as CF 4 , SF 6 etc., will generate yttrium fluoride compounds. At the same time, since the gas showerhead coating also contains anodic aluminum oxide, aluminum fluoride compounds will also be generated. These two compounds are insoluble in ordinary acids and thus need to be filtered out to avoid affecting the purity of yttrium oxide. Optionally, the material of the filter is PFA (tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer) or PTFE (polytetrafluoroethylene), and the pore size of the filter is preferably 0.1 - 0.2 μm.

[0066] Step S40: The filtered liquid to be treated is subjected to ion exchange treatment using a chelating resin column to remove metal cation impurities other than yttrium therein.

[0067] Specifically, the liquid to be treated may also contain metal ion impurities such as copper, iron, and aluminum. The sources of these impurity metal cations are mainly that the yttrium oxide raw material used in forming the yttrium oxide coating is not 100% pure and may contain metal ion impurities such as copper, iron, and aluminum, which will be released after being soaked in the acidic etching solution. Therefore, it is necessary to remove them from the liquid to be treated by ion exchange to avoid affecting the purity of the subsequent yttrium oxide. Optionally, the material of the chelating resin column used is high-purity polypropylene material or polytetrafluoroethylene material.

[0068] Before the liquid to be treated is processed through the chelating resin column, the pH value is adjusted to achieve the best metal ion selection ratio, so as to remove metal ion impurities such as copper, iron, and aluminum to the greatest extent. Optionally, before treatment, the pH value of the liquid to be treated is adjusted to 5.5 - 6.5.

[0069] In some embodiments, there may be residual broken resin particles in the liquid to be treated after ion exchange treatment when using the chelating resin column for ion exchange treatment. Therefore, after the ion exchange treatment is completed, a filter is used to filter and remove the broken resin particles that may be mixed in the liquid to be treated. The material and pore size of this filter are the same as those of the filter used in step S30, which will not be elaborated here.

[0070] Ion exchange treatment is a commonly used method for removing metal ion impurities in high-purity chemicals, and its detailed operation process will not be elaborated here.

[0071] Step S50, using the electrodialysis method to remove impurity anions and metal corrosion inhibitors, etc. from the liquid to be treated, and generating a yttrium ion-containing treatment liquid;

[0072] Specifically, since the acidic etching solution used in step S20 contains anions such as tartrate ions, these anions are not conducive to the purity of the subsequent yttrium oxide recovery. Therefore, in this step, the electrodialysis method is used to remove these anion impurities and impurities such as metal corrosion inhibitors. The electrodialysis method is a commonly used technical means for selectively removing impurities driven by direct current. For the specific principle, please refer to Figure 4, the cation exchange membrane 303 and the anion exchange membrane 302 are alternately placed in the electrodialysis cell. The various electrode chambers are laminated in multiple layers through two types of separators in the middle, and a pair of electrodes, the cathode 301 and the anode 304, are arranged at both ends. When the liquid to be treated is supplied to the first electrode chamber 42, yttrium cations permeate through the cation exchange membrane 303 towards the cathode 301 and move to the adjacent product chamber 41 on the left. However, since the cathode side of the product chamber 41 is separated by the anion exchange membrane 302, the yttrium cations cannot move to the more left-side electrode water chamber, so that they can fully react with the electrolyte solution in the product chamber 41. Anions move from the first electrode chamber 42 to the adjacent second electrode chamber 43 on the right in the same way, react with ammonia water to form ammonium salts, and then are discarded. In this way, anion impurities are effectively removed. And the metal corrosion inhibitor, as an organic molecule, has a large molecular volume and will not pass through the cation exchange membrane 303 and the anion exchange membrane 302 into the adjacent electrode chambers, but remains in the first electrode chamber 42 and is discarded. Therefore, the metal corrosion inhibitor can also be effectively removed. Optionally, the electrodialysis equipment used is LANRAN@EX-4S produced by Hangzhou Blue Ray. The cation exchange membrane can optionally be an acid and alkali resistant cation membrane CT-4 or a standard homogeneous cation membrane CTG-10, and the anion exchange membrane can optionally be an acid and alkali resistant standard homogeneous anion membrane ATG-10 or AHT. An iridium-plated titanium plate of insoluble anode is used as the electrode material for the cathode and anode. The electrolyte concentration in all electrode chambers must be maintained at a certain level, otherwise the current cannot conduct.

[0073] In some embodiments, the system temperature during electrodialysis does not exceed 38 °C, and the current during electrodialysis does not exceed 100 A. The product chamber 41 preferably uses high-purity sulfuric acid or nitric acid as the electrolyte (acid solution), and its concentration is 0.1% - 5%, to avoid forming yttrium hydroxide precipitation in the product chamber 41.

[0074] The anion waste liquid chamber uses ammonia water to react with the anions passing through the anion membrane to generate the corresponding ammonium salts, and then discards and discharges them for waste treatment.

[0075] Step S60, use high-purity ammonia water to adjust the pH value of the yttrium ion-containing treatment liquid collected after electrodialysis to convert yttrium salt into yttrium hydroxide;

[0076] Specifically, the high-purity ammonia water used is of UPS grade or above SEMI G3 level, and the ratio of the added ammonia water to the yttrium ion-containing treatment liquid is 4:1 - 10:1. To improve the reaction efficiency, a stirrer is used for stirring when adding ammonia water. The stirring rate of the stirrer is 50 - 300 rpm, the solution temperature is 20 - 50 °C, and the stirring time is 1 - 3 hours. Optionally, the adjusted pH value is between 8.5 - 9.5.

[0077] Step S70, use a filter membrane to filter, wash, and centrifuge to collect yttrium hydroxide, and then calcine it after drying to obtain high-purity yttrium oxide.

[0078] Specifically, the filter material is preferably PFA or polytetrafluoroethylene, and the pore size of the filter is preferably 0.5 - 5 μm. The filtered crude yttrium hydroxide is washed with ultrapure water, and then the yttrium hydroxide and water are centrifuged and separated using a centrifuge, repeating this process 3 times.

[0079] Optionally, the drying temperature is 60 - 100 °C, the calcination temperature is 700 - 900 °C, and the calcination time is 1 - 5 hours.

[0080] The yttrium oxide sample collected using the above recycling method is detected using inductively coupled plasma optical emission spectrometry (ICP - OES) or inductively coupled plasma mass spectrometry (ICP - MS). The sample purity is greater than 99.9%, and this purity enables the yttrium oxide sample to be used as a reaction source material when coating the surface of semiconductor device components with yttrium oxide using a chemical vapor deposition method. It can be calculated that the recovery rate of yttrium oxide is approximately 83.6% - 91.3%.

[0081] In addition, the surface of the component processed using the above recycling method is characterized using an optical microscope. Please also refer to Figure 5 and Figure 6 , Figure 5 a and Figure 6 a is a schematic diagram of the surface morphology of the aluminum substrate of the component before being coated with a yttrium oxide coating. Figure 5 b and Figure 6 b is a schematic diagram of the surface morphology of the aluminum substrate of the component after being processed using the above recycling method. Among them, Figure 5 is the overall surface morphology of the component, Figure 6 is the surface morphology under an optical microscope. It can be seen that while obtaining a high - purity yttrium oxide product using the above recycling method, the surface of the aluminum substrate basically maintains its original surface morphology, and the change range of its surface roughness does not exceed 10 nm.

[0082] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not imply the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0083] The above - mentioned is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A method for recovering an yttrium oxide coating on a semiconductor device component, wherein the component comprises a metal substrate and an yttrium oxide coating disposed on the metal substrate, characterized in that: The steps include: Etching step: immersing the component in an acidic etching solution to dissolve the yttrium oxide coating to form a solution to be treated, wherein the acidic etching solution is a weak acid solution, and the metal substrate substantially maintains the original surface morphology after etching is completed; Impurity removal step: removing impurity components in the liquid to be treated to obtain a yttrium ion-containing treatment liquid, wherein the impurity components are at least one of insoluble impurities, metal cations other than yttrium, impurity anions or organic molecules; Recovery step: adjusting the pH value of the yttrium ion-containing treatment solution to obtain yttrium hydroxide precipitate, and obtaining yttrium oxide product after filtering, drying and calcining.

2. The method for recovering yttrium oxide coating on semiconductor equipment parts according to claim 1, characterized in that: The impurity anions and / or the organic molecules are removed by electrodialysis.

3. The method for recovering yttrium oxide coating on semiconductor equipment parts according to claim 2, characterized in that: When the electrodialysis method is used, the electrolyte in the electrodialysis cell is at least one of sulfuric acid and nitric acid.

4. The method for recovering yttrium oxide coating on semiconductor equipment parts according to claim 1, characterized in that: The weak acid solution comprises one or more of tartaric acid, lactic acid, malic acid, citric acid, ascorbic acid, gluconic acid or aspartic acid.

5. The method for recovering yttrium oxide coating on semiconductor equipment parts as claimed in claim 4, characterized in that: The acidic etching solution also contains a metal corrosion inhibitor, which contains one or more of benzimidazole, methylbenzimidazole, 8-hydroxyquinoline, catechol, sorbitol, maltitol, mannitol, and glucose.

6. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 4, characterized in that: The acidic etching solution has a concentration of 10% to 100% and a temperature of 20 to 50°C.

7. The method for recovering yttrium oxide coating on semiconductor equipment parts as claimed in claim 1, characterized in that: The method further comprises the step of removing organic polymer contaminants on the surface of the component using an organic solvent.

8. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 1, characterized in that: The poorly soluble impurities include one or more of aluminum fluoride or yttrium fluoride, and the metal cations other than yttrium include one or more of copper, iron or aluminum.

9. The method for recovering yttrium oxide coating on semiconductor device parts as claimed in claim 8, characterized in that: The metal cations other than yttrium are removed using an ion exchange treatment.

10. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 9, characterized in that: Before the ion exchange treatment is performed, the method further comprises the step of adjusting the pH value of the liquid to be treated to 5.5-6.

5.

11. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 3, characterized in that: When the impurity anions and / or the organic molecules are removed by electrodialysis, the temperature of the electrodialysis system does not exceed 38° C., and the current during electrodialysis does not exceed 100A.

12. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 1, characterized in that: The pH value of the obtained yttrium ion treatment solution is adjusted using ammonia water, and the adjusted pH value is between 8.5 and 9.5 to obtain the yttrium hydroxide precipitate.

13. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 12, characterized in that: The method also comprises the steps of: centrifugally separating the yttrium hydroxide precipitate, drying it, and calcining it to obtain a yttrium oxide product.

14. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 13, characterized in that: The drying temperature of the drying is 60-100°C.

15. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 14, characterized in that: The calcination temperature is 700-900° C., and the calcination time is 1-5 hours.

16. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 1, characterized in that: The material of the metal substrate is aluminum or aluminum alloy.

17. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 16, characterized in that: An anodized aluminum layer is also provided on the metal substrate.

18. The method for recovering yttrium oxide coating on semiconductor device parts according to claim 17, characterized in that: The semiconductor equipment component is at least one of a gas shower head, a mounting substrate, an equipment plate, a gas pipeline, a gas shower head, a dielectric window or a liner.

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