Polishing liquid supply device and polishing system

Abstract

The application belongs to the field of semiconductor processing, and particularly relates to a polishing liquid supply device and a polishing system. The polishing liquid supply device comprises: a liquid storage tank, which is used for mixing polishing liquid raw materials to obtain a raw material mixture; an exciter, which is connected with a raw material mixture outlet and is used for exciting long afterglow light particles in the raw material mixture to obtain polishing liquid; and a control assembly, which is connected with the liquid storage tank and is used for controlling the feeding amount of the polishing liquid raw materials. The polishing liquid supply device can provide uniform and light-stable polishing liquid, guarantee polishing uniformity, be suitable for intermittent polishing and double-sided polishing processes, and can improve polishing flexibility.

Description

Technical Field

[0001] This application belongs to the field of semiconductor processing, specifically relating to a polishing liquid supply device and a polishing system. Background Technology

[0002] Photo-assisted chemical mechanical polishing (PACMP) utilizes the synergistic effect of photochemistry and mechanics to achieve controllable surface processing with nanoscale precision. However, in double-sided polishing processes, the enclosed polishing chamber and the relatively moving polishing disk structure make it difficult to introduce an ultraviolet light source in situ into the polishing slurry-wafer contact area. This lack of effective photoexcitation severely limits the enhancement effect of photochemical reactions on the oxidation and corrosion of SiC wafer surfaces. Therefore, there is an urgent need to develop a novel polishing slurry supply device and polishing system to improve process flexibility. Utility Model Content

[0003] This application aims to at least partially address one of the technical problems in the related art. To this end, this application proposes a polishing liquid supply device and a polishing system. This system can provide a uniform and stable polishing liquid, ensuring polishing uniformity, and is suitable for intermittent polishing and double-sided polishing processes, thereby improving polishing flexibility.

[0004] A first aspect of this application discloses a polishing liquid supply device, comprising: a storage tank, including a storage tank shell and a stirring assembly, wherein the storage tank shell is provided with a polishing liquid raw material inlet and a raw material mixture outlet, and the stirring assembly is disposed inside the shell; the storage tank is used to mix the polishing liquid raw material to obtain a raw material mixture; an exciter, connected to the raw material mixture outlet, for exciting long afterglow luminescent particles in the raw material mixture to obtain polishing liquid, the exciter being provided with a first polishing liquid outlet for outputting the polishing liquid; and a control assembly, connected to the storage tank, for controlling the feed rate of the polishing liquid raw material.

[0005] Therefore, using this polishing liquid supply device can fully mix the polishing liquid raw materials, making the luminescence characteristics of the long-afterglow luminescent particles in the polishing liquid more uniform and stable, effectively preventing excessive local reactions during the polishing process and ensuring the uniformity of the polishing effect. At the same time, the long-afterglow particles in the polishing liquid can continue to emit light after being excited. Even after ultraviolet irradiation is stopped, this luminescence effect can continue for several hours, continuously stimulating the photocatalytic reaction and maintaining catalytic activity. It is suitable for intermittent polishing and double-sided polishing processes, improving polishing flexibility and applicability.

[0006] According to an embodiment of this application, the storage tank shell is provided with a polishing liquid inlet and a second polishing liquid outlet. The polishing liquid inlet is connected to the first polishing liquid outlet, and the second polishing liquid outlet is used to output the polishing liquid in the storage tank. Thus, the polishing liquid obtained after excitation in the exciter is returned to the storage tank for stirring, preventing sedimentation and stratification, and ensuring the high uniformity and stability of the polishing liquid composition and the distribution of long-afterglow luminescent particles.

[0007] According to an embodiment of this application, the polishing liquid supply device further includes: multiple component detectors, disposed within the liquid storage tank and connected to the control component, for detecting the composition and content of the raw material mixture. This allows for real-time monitoring of the concentration of each raw material in the mixture, timely replenishment of each component, ensuring stable luminescence intensity, and making the photocatalytic reaction more constant.

[0008] According to an embodiment of this application, the polishing liquid supply device further includes a temperature detector, disposed inside the storage tank and connected to the control component, for detecting the temperature of the material inside the storage tank. Thus, the temperature detector can monitor the temperature in real time, ensuring that the chemical reaction, excitation of luminescent particles, and catalytic activity of the polishing liquid are under suitable conditions, thereby guaranteeing the stability of the polishing liquid's performance.

[0009] According to an embodiment of this application, the exciter includes: an exciter housing with a raw material mixture inlet at the bottom and a first polishing liquid outlet at the top; an excitation coil disposed inside the exciter housing, with one end connected to the raw material mixture inlet and the other end connected to the first polishing liquid outlet along its length; and an ultraviolet light source disposed inside the exciter housing for irradiating the raw material mixture in the exciter coil with ultraviolet light. Thus, when the polishing liquid enters the excitation coil, the ultraviolet light source continuously irradiates the polishing liquid inside the coil as it flows through the coil, exciting the long-afterglow luminescent material therein and causing it to produce a photocatalytic effect.

[0010] According to an embodiment of this application, the excitation coil is spiral-shaped and arranged around the ultraviolet light source. This design facilitates longer irradiation time and more uniform excitation, improves excitation efficiency, and ensures uniform luminescence of long-afterglow particles.

[0011] According to an embodiment of this application, the polishing liquid supply device further includes multiple raw material storage tanks, each connected to the polishing liquid raw material inlet. This allows the raw materials to be transported to the storage tanks for uniform mixing.

[0012] According to the embodiments of this application, refer to Figure 2The multiple raw material storage tanks include an abrasive slurry tank A, an oxidant tank B, a long-afterglow luminescent particle tank C, and a photocatalyst tank D. Multiple polishing slurry raw material inlets are provided on the tank shells, with each storage tank connected to one of these inlets. Therefore, by supplying different raw materials through multiple storage tanks, the amount of each raw material added can be more precisely controlled. When a certain raw material is insufficient, the corresponding storage tank can be quickly and accurately replenished without stopping the operation of the entire polishing slurry supply system, thus improving production efficiency.

[0013] A second aspect of this application provides a polishing system comprising: a polishing liquid supply device as described above; and a polishing device connected via a connecting pipe to a second polishing liquid outlet of the storage tank for supplying the polishing liquid to the polishing device. Thus, this polishing system possesses all the features and advantages of the polishing liquid supply device described above, which will not be elaborated further here. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of a polishing liquid supply device according to an embodiment of this application.

[0015] Figure 2 This is a schematic diagram of the polishing liquid supply device according to another embodiment of this application.

[0016] Figure 3 This is a schematic diagram of the structure of an exciter according to an embodiment of this application.

[0017] Figure 4 This is a schematic diagram of the polishing liquid supply device according to another embodiment of this application.

[0018] Figure 5 This is a schematic diagram of the polishing liquid supply device according to another embodiment of this application.

[0019] Figure 6 This is a schematic diagram of the structure of a polishing system according to an embodiment of this application.

[0020] Figure label:

[0021] 10: Storage tank; 11: Storage tank shell; 12: Stirring assembly; 20: Exciter; 21: Exciter shell; 22: Excitation coil; 23: Ultraviolet light source; 30: Control assembly; 40: Component detector; 50: Temperature detector; 60: Raw material storage tank; 61: Abrasive slurry tank; 62: Oxidant tank; 63: Long afterglow luminescent particle tank; 64: Photocatalyst tank.

[0022] A: Polishing slurry raw material inlet; A1: First polishing slurry raw material inlet; A2: Second polishing slurry raw material inlet; A3: Third polishing slurry raw material inlet; A4: Fourth polishing slurry raw material inlet; B: Raw material mixture outlet; C: First polishing slurry outlet; D: Polishing slurry inlet; E: Second polishing slurry outlet; F: Raw material mixture inlet. Detailed Implementation

[0023] The embodiments of this application are described in detail below, with examples of these embodiments illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0024] During polishing, SiC is chemically inert and difficult to remove during mechanical grinding. Strong oxidizing free radicals are highly reactive and can react with SiC wafers to form a SiO2 oxide layer on the surface. This SiO2 oxide layer has low hardness and is easier to remove during mechanical grinding. However, the generation efficiency of strong oxidizing free radicals is low and they are extremely unstable, leading to uneven polishing slurry quality and low polishing efficiency. Long-afterglow luminescent particles can absorb and store ultraviolet light energy, slowly releasing ultraviolet light after ultraviolet irradiation stops, and continuously emitting light. In related technologies, long-afterglow luminescent particles are pre-excited and added to the polishing slurry during polishing. This process can lead to uneven distribution of long-afterglow luminescent particles and other materials in the polishing slurry, potentially resulting in insufficient contact and reaction, affecting the generation efficiency of active free radicals. Uneven distribution of long-afterglow luminescent particles can also cause localized intense and slow reactions on the SiC wafer surface, leading to uneven surface quality. Furthermore, it is difficult to ensure consistent quality of each batch of polishing slurry, increasing the difficulty and cost of quality monitoring during production.

[0025] Based on the above research, this application directly mixes long-afterglow luminescent particles with other raw materials, ensuring sufficient contact and reaction, and guaranteeing uniform distribution of all components in the polishing slurry. This helps provide a stable chemical reaction environment during polishing, resulting in a more uniform polishing effect and improved controllability of the polishing process. Secondly, the uniformly mixed polishing slurry can function more effectively during polishing, promoting chemical reactions on the SiC wafer surface and generating a more uniform SiO2 oxide layer. This helps improve the quality of the polished surface, reducing surface defects and inhomogeneities. Finally, the polishing slurry requires no additional mixing step and can be used directly for polishing, reducing preparation time before polishing, improving production efficiency, and enhancing the stability of the production process.

[0026] In view of this, the first aspect of this application proposes a polishing liquid supply device, referring to... Figure 1The polishing liquid supply device includes: a storage tank 10, comprising a storage tank shell 11 and a stirring assembly 12, wherein the shell is provided with a polishing liquid raw material inlet A and a raw material mixture outlet B, and the stirring assembly 12 is disposed inside the storage tank shell 11; the storage tank 10 is used to mix the polishing liquid raw materials to obtain a raw material mixture; an exciter 20, connected to the raw material mixture outlet B, is used to excite the long afterglow luminescent particles in the raw material mixture to obtain polishing liquid; the exciter 20 is provided with a first polishing liquid outlet C for outputting the polishing liquid; and a control assembly 30, connected to the storage tank 10, is used to control the feed rate of the polishing liquid raw materials.

[0027] Therefore, by using this polishing liquid supply device, the long-afterglow luminescent particles are thoroughly mixed with other raw materials in the polishing liquid to form a relatively stable chemical system. This makes the luminescence characteristics of the long-afterglow luminescent particles in the polishing liquid more uniform and stable, effectively preventing excessive local reactions during the polishing process and ensuring the uniformity of the polishing effect. Simultaneously, the long-afterglow particles in the polishing liquid can continuously emit light after being excited. Even after ultraviolet irradiation stops, this luminescence effect can continue for several hours, continuously stimulating photocatalytic reactions and maintaining catalytic activity. This makes it suitable for intermittent polishing and double-sided polishing processes, improving polishing flexibility and applicability.

[0028] According to an embodiment of this application, the storage tank shell 11 is provided with a polishing liquid inlet D and a second polishing liquid outlet E. The polishing liquid inlet D is connected to the first polishing liquid outlet C, and the second polishing liquid outlet E is used to output the polishing liquid in the storage tank. Thus, the polishing liquid obtained after excitation in the exciter is returned to the storage tank for stirring, preventing sedimentation and stratification of the polishing liquid, and ensuring the high uniformity and stability of the polishing liquid composition and the distribution of long-afterglow luminescent particles.

[0029] According to the embodiments of this application, refer to Figure 2 The polishing liquid supply device also includes multiple component detectors 40, installed inside the storage tank 10 and connected to the control component 30, for detecting the composition and content of the raw material mixture. This allows for real-time monitoring of the concentration of each raw material in the mixture, timely replenishment of each component, ensuring stable luminescence intensity, and making the photocatalytic reaction more constant.

[0030] It is understandable that the number of component detectors corresponds one-to-one with the type of raw material, that is, each type of raw material is equipped with a dedicated component detector.

[0031] According to the embodiments of this application, refer to Figure 2The polishing liquid supply device also includes a temperature detector 50, which is installed inside the storage tank 10 and connected to the control component 30, for detecting the temperature of the material inside the storage tank 10. Thus, the temperature detector can monitor the temperature in real time, ensuring that the chemical reaction, excitation of luminescent particles, and catalytic activity of the polishing liquid are under suitable conditions, thereby guaranteeing the stability of the polishing liquid's performance.

[0032] According to the embodiments of this application, refer to Figure 3 The exciter 20 includes: an exciter housing 21 with a raw material mixture inlet F at the bottom and a first polishing liquid outlet E at the top; an excitation coil 22 disposed inside the exciter housing 21, with one end connected to the raw material mixture inlet F and the other end connected to the first polishing liquid outlet E along its length; and an ultraviolet light source 23 disposed inside the exciter housing 21 for irradiating the raw material mixture in the excitation coil 22 with ultraviolet light. Thus, when the polishing liquid enters the excitation coil, the ultraviolet light source continuously irradiates the polishing liquid inside the coil, exciting the long-afterglow luminescent particles within it, causing them to undergo a photocatalytic reaction.

[0033] According to the embodiments of this application, refer to Figure 3 The excitation coil 22 is spiral-shaped and arranged around the ultraviolet light source. This design helps to extend the irradiation time and achieve uniform excitation, improving excitation efficiency and ensuring uniform luminescence of long-afterglow particles.

[0034] According to the embodiments of this application, refer to Figure 4 The polishing liquid supply device also includes multiple raw material storage tanks 60, each of which is connected to the polishing liquid raw material inlet A. This allows the raw materials to be transported to the storage tanks for uniform mixing.

[0035] It is understood that the number of raw material storage tanks is 4-10, such as 4, 5, 6, 7, 8, 9, or 10. The specific number of raw material storage tanks can be determined by the type of raw material, with one tank corresponding to one type of raw material. For example, 4 types of raw materials correspond to 4 tanks, 5 types of raw materials correspond to 5 tanks, 6 types of raw materials correspond to 6 tanks, 7 types of raw materials correspond to 7 tanks, 8 types of raw materials correspond to 8 tanks, 9 types of raw materials correspond to 9 tanks, and 10 types of raw materials correspond to 10 tanks.

[0036] According to the embodiments of this application, refer to Figure 5 The plurality of raw material storage tanks 60 include an abrasive slurry tank 61, an oxidant tank 62, a long afterglow luminescent particle tank 63, and a photocatalyst tank 64. Multiple polishing fluid raw material inlets are provided on the tank shell 11, and each raw material storage tank is connected to one of the polishing fluid raw material inlets. As an example, refer to... Figure 5The storage tank shell 11 is equipped with four polishing slurry inlets. The first polishing slurry inlet A1 is connected to the abrasive slurry tank 61, the second polishing slurry inlet A2 is connected to the oxidant tank 62, the third polishing slurry inlet A3 is connected to the long afterglow luminescent particle tank 63, and the fourth polishing slurry inlet A4 is connected to the photocatalyst tank 64. Thus, by supplying different raw materials through multiple storage tanks, the amount of each raw material added can be more precisely controlled. When a certain raw material is insufficient, the corresponding storage tank can be quickly and accurately replenished without stopping the operation of the entire polishing slurry supply device, thereby improving production efficiency.

[0037] As an example, the oxidant includes at least one of H2O2 and K2S2O8.

[0038] As an example, long-afterglow luminescent particles include Ca2PO4Cl:Eu 2+ SrB4O7:Ce 3+ At least one of them.

[0039] As an example, photocatalysts include at least one of FeC2O4 and Fe2O3.

[0040] As a specific example, H2O2 is used as the oxidant, FeC2O4 as the catalyst, and the long afterglow particles are Ca2PO4Cl:Eu. 2+ The process of free radical generation is as follows:

[0041] (1) Ultraviolet light irradiation decomposes the oxidant H2O2, producing hydroxyl radicals (•OH).

[0042] H2O2+ hυ → 2 •OH

[0043] (2) Fe in photocatalyst 2+ Catalytically decomposes the oxidant H2O2 to produce hydroxyl radicals (•OH).

[0044] Fe 2+ + H2O2→ Fe 3+ + OH - + •OH

[0045] (3) Under the action of ultraviolet light, Fe 3+ It reacts with H2O2 to produce Fe 2+ To achieve Fe 2+ and Fe 3+ The cyclical transformation between these processes sustains the continuous progress of the light reaction.

[0046] Fe 3+ + H2O2→ Fe 2+ + HO2•+ H +

[0047] The complete operation process of the liquid supply device is as follows: First, long afterglow luminescent particles Ca2PO4Cl:Eu 2+ H2O2, FeC2O4, and abrasive slurry are mixed evenly in a storage tank beforehand. The mixed raw materials then enter the exciter, where long-afterglow luminescent particles (Ca2PO4Cl:Eu) are produced. 2+ The polishing slurry is irradiated with ultraviolet light inside the exciter, absorbing and storing the light energy. After the ultraviolet irradiation stops, the polishing slurry is returned from the exciter to the storage tank and stirred for a period of time. During this time, long afterglow particles Ca2PO4Cl:Eu are produced. 2+ Releasing the stored light energy can sustain the Fe process during the aforementioned free radical generation. 3+ To Fe 2+ The conversion ensures a sufficient concentration of Fe in the system. 2+ It continuously catalyzes the decomposition of oxidants, continuously generating hydroxyl radicals, and providing sustained chemical reactivity for the polishing process.

[0048] A second aspect of this application provides a polishing system, referring to... Figure 6 The polishing system includes: a polishing liquid supply device as described above; and a polishing device 70, connected to the second polishing liquid outlet E of the storage tank 10 via a connecting pipe, for supplying the polishing liquid to the polishing device 70. Thus, the polishing system possesses all the features and advantages of the polishing liquid supply device described above, which will not be elaborated further here.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A polishing liquid supply device, characterized in that, include: A storage tank includes a storage tank shell and a stirring assembly. The storage tank shell is provided with a polishing liquid raw material inlet and a raw material mixture outlet. The stirring assembly is disposed inside the storage tank shell. The storage tank is used to mix the polishing liquid raw material to obtain a raw material mixture. An exciter, connected to the outlet of the raw material mixture, is used to excite the long-afterglow luminescent particles in the raw material mixture to obtain a polishing liquid. The exciter is provided with a first polishing liquid outlet for outputting the polishing liquid. A control component, connected to the storage tank, is used to control the feed rate of the polishing slurry raw material.

2. The polishing liquid supply device according to claim 1, characterized in that, The storage tank has a polishing liquid inlet and a second polishing liquid outlet on its shell. The polishing liquid inlet is connected to the first polishing liquid outlet, and the second polishing liquid outlet is used to output the polishing liquid in the storage tank.

3. The polishing liquid supply device according to claim 1, characterized in that, Also includes: Multiple component detectors are installed inside the storage tank and connected to the control component to detect the composition and content of the raw material mixture.

4. The polishing liquid supply device according to claim 1, characterized in that, Also includes: A temperature detector is installed inside the liquid storage tank and connected to the control component to detect the temperature of the material inside the liquid storage tank.

5. The polishing liquid supply device according to claim 1, characterized in that, The exciter includes: The activator housing has a raw material mixture inlet at its lower part and a first polishing liquid outlet at its upper part. An excitation coil is disposed inside the exciter housing, with one end in the length direction connected to the inlet of the raw material mixture and the other end in the length direction connected to the outlet of the first polishing liquid. An ultraviolet light source is located inside the exciter housing and is used to irradiate the raw material mixture in the excitation coil with ultraviolet light.

6. The polishing liquid supply device according to claim 5, characterized in that, The excitation coil is spiral-shaped and arranged around the ultraviolet light source.

7. The polishing liquid supply device according to claim 1, characterized in that, It also includes multiple raw material storage tanks, each of which is connected to the polishing fluid raw material inlet.

8. The polishing liquid supply device according to claim 7, characterized in that, The plurality of raw material storage tanks include an abrasive slurry tank, an oxidant tank, a luminescent material tank, and a catalyst tank. The shell of the storage tank is provided with a plurality of polishing liquid raw material inlets, and each raw material storage tank is connected to one of the polishing liquid raw material inlets.

9. A polishing system, characterized in that, include: The polishing liquid supply device according to any one of claims 1-8; The polishing device is connected to the second polishing liquid outlet of the storage tank via a connecting pipe, and is used to deliver the polishing liquid to the polishing device.

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