A method for solving the problem of particles generated at the wafer processing end of a quartz boat

Abstract

The present application belongs to the technical field of semiconductor wafer manufacturing equipment, and particularly relates to a method for solving the generation of particulate matter at the wafer processing technology end of a quartz boat, which comprises an external environment generated pollution treatment method and an internal environment generated pollution treatment method. The external environment generated pollution treatment method comprises a machining external environment pollution treatment method, a fire machining external environment pollution treatment method and final product cleaning. The internal environment generated pollution treatment method comprises that the slotting machining of three slot rods required by one quartz boat is completed in one clamping, and the slotting of the three slot rods on the same mounting surface is completed under one linear motion of a slotting cutter. After the slotting of the three slots on the same mounting surface is completed, the slotting of the next mounting surface is continued. The present application reduces the vibration and friction during the process reaction on the mounting surface, and reduces the generation of particulate matter.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor wafer manufacturing equipment technology, and particularly relates to a method for solving the problem of particulate matter generated by quartz boats in wafer manufacturing processes. Background Technology

[0002] Quartz boats primarily function as wafer carriers and positioners in chip manufacturing processes. During high-temperature processes (such as diffusion, oxidation, and annealing), quartz boats safely transfer and support wafers, effectively preventing wafer contamination, ensuring process stability, and thus improving chip manufacturing yield. Therefore, quartz boats play a crucial role in semiconductor wafer manufacturing. my country's semiconductor industry started relatively late, and currently, domestically produced quartz boats generally only meet the requirements of 28nm and below chip manufacturing processes, failing to meet the current advanced 5nm and above chip manufacturing standards. The most prominent problem is the excessive particulate matter content in quartz boats used in wafer manufacturing. The manufacturing process of quartz boats involves two key steps: machining and heat treatment. In the machining stage, four components—the top plate, slot bar, reinforcing bar, and flange—are precision machined. Subsequently, these four components are welded together through heat treatment to form a complete quartz boat.

[0003] The sources of quartz boat particulate matter can be mainly divided into two categories: external environmental pollution and internal environmental generation.

[0004] External environmental pollution refers to particulate matter pollution caused by external environmental operations during the manufacturing of quartz boats. In the machining environment, the main pollutants include: oil stains on equipment, wax used for clamping and fixing, waste quartz fragments, and sub-loss fracture layers on the surface of parts. In the fire processing environment, the main pollutants involve: airborne dust, pollutants carried by tooling fixtures, and pollutants introduced by the mouth and nose.

[0005] Internally generated particulate matter refers to particulate matter produced during high-temperature processes (such as diffusion, oxidation, and annealing) carried by a quartz boat due to improper design or fabrication. Specifically, the internally generated particulate matter referred to here is particulate matter generated during high-temperature processes (such as diffusion, oxidation, and annealing) carried by a quartz boat, caused by improper design or fabrication of the quartz boat (e.g., raised edges on the mounting surface, or incomplete sintering to achieve transparency).

[0006] Existing technologies lack systematic solutions for decontamination and structural optimization, making it impossible to suppress particulate matter generation at the source, resulting in high particle density and low yield on the wafer surface. Summary of the Invention

[0007] The purpose of this invention is to address the aforementioned technical problems by providing a method for resolving particulate matter generation during wafer fabrication processes using quartz boats. This method reduces vibration and friction on the mounting surface during process reactions, thereby reducing particulate matter generation.

[0008] In view of this, the present invention provides a method for solving the problem of particulate matter generated by quartz boats in wafer fabrication processes, including a method for treating contamination generated by the external environment and a method for treating contamination generated by the internal environment. The method for treating contamination generated by the external environment includes: a method for treating contamination generated by machining, a method for treating contamination generated by heat treatment, and cleaning of the final product. The method for treating contamination generated by the internal environment includes completing the grooving of the three slot bars required for a quartz boat in one clamping operation, and completing the grooving of the three slot bars on the same mounting surface in one linear movement of the grooving cutter. After all three slots on the same mounting surface are grooved, the grooving of the next mounting surface is continued.

[0009] In this technical solution, a quartz boat is equipped with three slotted rods. If the flatness and parallelism of the plane formed by the mounting surfaces of the three slotted rods of the quartz boat are not good and the dimensional consistency is poor, it is difficult to ensure the flatness and parallelism of the wafer mounting surface formed after fire processing and welding. When the wafer is processed on the mounting surface with substandard flatness and parallelism, it is prone to vibration, which in turn causes friction with the mounting surface and generates particulate matter.

[0010] By using a single clamping and machining method for the three slotted bars, the dimensional consistency of the material is ensured. This not only guarantees excellent flatness of the plane formed by the mounting surfaces of the three slotted bars on the quartz boat, but also ensures that the parallelism of this plane relative to the flange reference surface remains consistent, reducing vibration and friction during processing on the mounting surface and minimizing the generation of particulate matter.

[0011] Furthermore, the grooving tool is regularly repaired, with the tool tip RX being ground to a range of R0.2 to R0.5; the grinding angle F of the tool grinding head is between 87° and 89°.

[0012] In this technical solution, mechanical scratches and extrusion marks on the mounting surface of the slotting bar not only create a stepped feel but also increase the surface roughness. This increased roughness accelerates the friction between the mounting surface and the wafer, and particulate matter is generated during this friction process. By regularly adjusting the parameters of the slotting tool, the removal of quartz powder during processing can be facilitated, preventing extrusion marks on the cutting surface, reducing friction between the mounting surface and the wafer, and minimizing particulate matter generation.

[0013] Furthermore, the edges of the mounting surface of the slot bar are rounded, and the radius R should be between R1.0 and R1.3.

[0014] In this technical solution, the rolled edge protrusion of the slot bar wafer mounting surface causes the wafer-to-slot bar mounting surface to change from surface contact to point contact of the protruding part, which intensifies the friction between the mounting surface and the silicon wafer and significantly increases the risk of particulate matter generation. Chamfering the edges of the slot bar mounting surface and removing the material at the edges can effectively reduce or avoid the melting and deformation of the edge material under high-temperature polishing, thereby preventing the formation of rolled edge protrusions at the edges.

[0015] Furthermore, the mounting surface of the slotted bar wafer is subjected to fire polishing, which proceeds from the inside of the mounting surface outwards along the edges.

[0016] In this technical solution, flame polishing polishes the originally whitish, frosted surface of the processed surface due to the damaged layer to a transparent state at high temperature. The transparency of the product surface indicates that the broken layer on the surface has been melted and completely removed. Flame polishing is performed from the inside of the mounting surface to the outer edges, ensuring that the flame impact force is from the inside out, so that the edges of the mounting surface are less likely to develop inward bulging.

[0017] Furthermore, fire polishing is required to achieve a transparent state for the product.

[0018] In this technical solution, after the quartz boat parts are machined and ground, a sub-damaged fracture layer will be generated on the surface of the parts. This fracture layer is particulate matter and has a whitish frosted state. After the product is polished, it becomes transparent and there is no fracture layer residue on the product surface.

[0019] Furthermore, the quartz boat product is flame-polished as a whole after the fire-processing welding is completed.

[0020] In this technical solution, during the flame processing and welding of the finished quartz boat, fog will be generated at the welding site. The fog is a white, opaque silica volatile that adheres to the surface of the product. The fog is essentially particulate matter, and flame polishing can remove the surface fog.

[0021] Furthermore, the method for treating external environmental pollution from machining includes first cleaning the parts at high temperature and then cleaning them with hydrofluoric acid after machining.

[0022] In this technical solution, during the machining process, the product will inevitably be contaminated by equipment oil, wax used for clamping and fixing, and waste quartz fragments. Therefore, the following high-temperature cleaning method can be used for effective removal. Quartz material is a hard and brittle material; during the finishing process, tools with a grit size of 200#-500# are typically used for precision machining. The surface roughness after finishing needs to be controlled within Ra1.2. However, during machining and tool grinding, a sub-damaged fracture layer inevitably forms on the surface of the parts. This fracture layer adheres to the product surface, with a depth ranging from 0.005mm to 0.02mm. The sub-damaged fracture layer on the surface can be effectively removed by hydrofluoric acid cleaning. Controlling the cleanliness of the heat treatment room environment; regularly cleaning the fixtures; and ensuring that operators wear masks, hats, and gloves during operation are also important. The product undergoes welding, grinding, and fire polishing processes, which inevitably introduce some particulate matter. After the product is processed, it needs to be cleaned to remove the particulate matter from the product surface.

[0023] Furthermore, the high-temperature cleaning method is as follows: First, use a sponge dipped in degreasing solution to wipe the product surface, then rinse thoroughly with pure water to ensure that there is no degreasing solution residue on the surface. Then, immerse the product in a cleaning tank with a water temperature of 95°C or higher for 5 minutes. After 5 minutes, turn the parts over and continue to soak for 5 minutes. After 10 minutes, take out the product, wipe the surface again with a sponge dipped in degreasing solution, and rinse thoroughly with pure water to ensure that there is no degreasing solution residue on the surface. Next, fill a boiling tank with pure water, heat the water temperature to 95°C or higher, and put the product into the boiling tank for 15 minutes of high-temperature boiling cleaning. After taking out the parts, rinse with pure water for more than 1 minute.

[0024] Furthermore, the hydrofluoric acid cleaning method is as follows: after rinsing with pure water, the parts are immersed in a 15% hydrofluoric acid bath for 1 hour to remove the broken layer on the surface of the product with a thickness of about 0.005mm to 0.02mm. After the hydrofluoric acid cleaning is completed, the parts are rinsed with pure water for more than 1 minute, and then the product is immersed in a pure water bath for 20 minutes. After that, the product is rinsed with pure water for another 10 minutes on a pure water rinsing table.

[0025] In this technical solution, after cleaning with hydrofluoric acid, the parts must be stored, handled, and rotated in turnover boxes or turnover vehicles to avoid secondary contamination of the parts.

[0026] Furthermore, the final cleaning method is as follows: First, pour the degreasing solution onto a wiping cloth, then wipe the product surface, rinse with pure water for more than 1 minute to ensure that the cleaning solution is completely removed, then immerse the product in a 10% nitric acid bath for 20 minutes, then rinse the product with pure water for more than 1 minute to ensure that the nitric acid is completely removed, finally immerse the product in a 5% hydrofluoric acid bath for 120 minutes, after the hydrofluoric acid is removed, rinse with pure water for more than 1 minute, then immerse in a pure water bath for 20 minutes, and finally place the product on a pure water rinsing platform for 3 minutes of pure water rinsing.

[0027] The beneficial effects of this invention are: 1. By using a method of clamping and machining three slotted bars in one go, the dimensional consistency of the bars can be ensured. This not only guarantees excellent flatness of the plane formed by the mounting surfaces of the three slotted bars on the quartz boat, but also ensures that the parallelism of this plane relative to the flange reference surface remains consistent, reducing vibration and friction during the process on the mounting surface and reducing the generation of particulate matter.

[0028] 2. By regularly adjusting the parameters of the grooving tool, it is possible to help remove quartz powder during processing, prevent extrusion marks on the cutting surface, reduce friction between the mounting surface and the wafer, and reduce the generation of particles.

[0029] 3. Chamfering the edges of the groove bar mounting surface and removing the material from the edges can effectively reduce or avoid the melting and deformation of the edge material under high-temperature polishing, thereby preventing the formation of rolled edges and protrusions at the edges.

[0030] 4. Polishing is performed from the inside of the mounting surface outwards along the edges to ensure that the flame impact force is from the inside out, thus preventing the mounting surface edges from curling inwards.

[0031] 5. Fire polishing should be performed to achieve a transparent state, ensuring that there is no broken layer residue on the product surface.

[0032] 6. After the quartz boat product has been flame-polished, the entire product is flame-polished.

[0033] 7. During the flame processing and welding of quartz boat finished products, fog will be generated at the welding site. The fog is a white opaque silica volatile substance attached to the surface of the product. The fog is essentially particulate matter. Flame polishing can remove the fog from the surface.

[0034] 8. The cleanliness of the packaged product itself is determined by high-temperature cleaning, hydrofluoric acid cleaning, and final product cleaning. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of a quartz boat structure; Figure 2 This is a schematic diagram of the grooving process; Figure 3 It is a raised, rolled edge after the sharp corners and edges are polished; Figure 4 It is a raised edge after the chamfered corner is polished; Figure 5 The surface edge radius R should be between R1.0 and R1.3 after polishing. Figure 6 This is a schematic diagram of a slotted bar mounting surface supporting a wafer; Figure 7 This is a schematic diagram of the surface polishing process on a wafer. Figure 8 This is a schematic diagram of a chamfering tool; Figure 9 This is a schematic diagram of the chamfering tool's machining trajectory; Figure 10 This is a schematic diagram of the fabrication process for the mounting surface of a slotted bar wafer; Figure 11 This is a schematic diagram of the cloud-like fog at the welding section; Figure 12 These are schematic diagrams showing the transparent state and the whitish frosted state; Figure 13 This is a 500x magnified microscopic image after fire polishing; Figure 14 This is a defect distribution diagram of a wafer manufactured using the quartz boat of Comparative Example 1; Figure 15 The image shows the EDS energy spectrum of a wafer manufactured using the quartz boat of Comparative Example 1. Figure 16 It is a defect distribution diagram of a wafer manufactured using the quartz boat of Example 1; The markings in the diagram are as follows: 1. Top plate; 2. Slot bar; 3. Reinforcing bar; 4. Wafer; 5. Flange; 6. Fixture; 7. Slotting tool; 8. Chamfering tool; 21. Mounting surface; 22. Rounded corner. Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0037] In the description of this application, it should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0038] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and are not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0039] It should be noted that in the description of this application, the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0040] It should be noted that, in this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0041] like Figure 1 As shown, the quartz boat mainly consists of four components: top plate 1, slotted bar 2, reinforcing bar 3, and flange 5, with the wafer 4 mounted on the mounting surface. The manufacturing process of the quartz boat includes two key steps: machining and heat treatment. First, in the machining stage, the four components—top plate 1, slotted bar 2, reinforcing bar 3, and flange 5—are precision machined. Subsequently, these four components are welded together through heat treatment to ultimately form a complete quartz boat.

[0042] A method for addressing particulate matter generation during wafer fabrication processes using quartz boats includes methods for treating contamination from both the external and internal environments. The methods for treating contamination from the external environment include: methods for treating contamination from machining processes, methods for treating contamination from heat treatment processes, and final product cleaning.

[0043] The method for treating external environmental pollution during machining involves first cleaning the parts at high temperature after machining, followed by cleaning with hydrofluoric acid. During machining, products inevitably become contaminated with oil from equipment, wax used for clamping and fixing, and waste quartz fragments. Therefore, the following high-temperature cleaning method can be used for effective removal. Quartz is a hard and brittle material; during the finishing process, tools with a grit size of 200#-500# are typically used for precision machining. The surface roughness after finishing needs to be controlled within Ra1.2. However, during machining and tool grinding, a sub-damaged fracture layer inevitably forms on the surface of the parts. This fracture layer adheres to the product surface, with a depth ranging from 0.005mm to 0.02mm. This sub-damaged fracture layer can be effectively removed by cleaning with hydrofluoric acid. Controlling the cleanliness of the heat treatment room environment; regularly cleaning the fixtures; and requiring operators to wear masks, hats, and gloves are also important. The high-temperature cleaning method is as follows: First, use a sponge dipped in degreasing solution to wipe the product surface, then rinse thoroughly with pure water to ensure that there is no degreasing solution residue on the surface. Next, immerse the product in a cleaning tank with a water temperature of 95℃ or higher for 5 minutes. After 5 minutes, turn the parts over and continue to soak for 5 minutes. After 10 minutes, take out the product, wipe the surface again with a sponge dipped in degreasing solution, and rinse thoroughly with pure water to ensure that there is no degreasing solution residue on the surface. Then, fill a boiling tank with pure water, heat the water temperature to above 95℃, and put the product into the boiling tank for 15 minutes of high-temperature boiling cleaning. After taking out the parts, rinse with pure water for more than 1 minute.

[0044] The hydrofluoric acid cleaning method is as follows: After rinsing with pure water, the parts are immersed in a 15% hydrofluoric acid bath for 1 hour to remove a broken layer approximately 0.005mm to 0.02mm thick from the surface. After hydrofluoric acid cleaning, the parts are rinsed with pure water for at least 1 minute, then immersed in a pure water bath for 20 minutes, followed by a 10-minute pure water rinse. After hydrofluoric acid cleaning, the parts must be stored, handled, and transferred in turnover boxes or carts to avoid secondary contamination.

[0045] Methods for handling external environmental pollution during fire processing: control the cleanliness of the fire processing room; clean the fixtures regularly; ensure that workers wear masks, hats, and gloves during operation; fire processing of products involves welding, grinding, fire polishing, and other processes, which inevitably introduce some particulate matter. After the product processing is completed, a final cleaning is required to remove particulate matter from the product surface.

[0046] The product undergoes welding, grinding, and fire polishing processes, inevitably introducing some particulate matter. After processing, a final cleaning is required to remove these particles from the product surface. The final cleaning method is as follows: First, pour a degreasing solution onto a wiping cloth and wipe the product surface. Rinse with pure water for at least 1 minute to ensure the cleaning solution is completely removed. Then, immerse the product in a 10% nitric acid bath for 20 minutes. Next, rinse with pure water for at least 1 minute to ensure the nitric acid is completely removed. Finally, immerse the product in a 5% hydrofluoric acid bath for 120 minutes. After the hydrofluoric acid is removed, rinse with pure water for at least 1 minute, then immerse in a pure water bath for 20 minutes. Finally, place the product on a pure water rinsing platform for 3 minutes of pure water rinsing.

[0047] The methods for treating pollution generated in the internal environment include: completing the grooving of the three slotted bars required for a quartz boat in one clamping operation, and completing the grooving of the three slotted bars on the same mounting surface in one linear movement of the grooving cutter. After all three slots on the same mounting surface are grooved, the grooving of the next mounting surface continues.

[0048] The grooving process diagram is as follows Figure 2 As shown, the machining steps for the slotted bar are as follows: Grooving is performed on the slotted bars: The three slotted bars 2 (with straightness controlled within 0.2) are fixed on the fixture 6. A grooving cutter 7 with a grit size of 270# to 400# is selected, ensuring the cutter width matches the groove width. The cutter operates along the radial direction of the slotted bar (cutting path of the red grooving cutter 7), machining from one end to the other, repeating this process until all grooves on the slotted bar are machined. Subsequently, the grooving cutter 7 cuts along the radial direction of the slotted bar (cutting path of the yellow grooving cutter 7) to cut the total length of the slotted bar.

[0049] A quartz boat is equipped with three slotted rods. If the flatness and parallelism of the plane formed by the mounting surfaces of the three slotted rods of the quartz boat are not good, and the dimensional consistency is poor, it is difficult to ensure the flatness and parallelism of the wafer mounting surface formed after fire processing and welding. When the wafer is processed on the mounting surface with substandard flatness and parallelism, it is prone to vibration, which in turn causes friction with the mounting surface and generates particulate matter.

[0050] By using a single clamping and machining method for the three slotted bars, the dimensional consistency of the material is ensured. This not only guarantees excellent flatness of the plane formed by the mounting surfaces of the three slotted bars on the quartz boat, but also ensures that the parallelism of this plane relative to the flange reference surface remains consistent, reducing vibration and friction during processing on the mounting surface and minimizing the generation of particulate matter.

[0051] The edges of the slot bar mounting surface should be rounded, with the radius (R) between R1.0 and R1.3. The raised edges of the slot bar wafer mounting surface cause the contact between the wafer and the slot bar mounting surface to change from surface contact to point contact with the raised portion, increasing friction between the mounting surface and the silicon wafer and significantly increasing the risk of particulate matter generation. Chamfering the edges of the slot bar mounting surface removes material from the edges, effectively reducing or preventing the edge material from melting and deforming under high-temperature polishing, thus preventing the formation of raised edges. Figure 3 The image shows the state after the sharp edges and corners of the mounting surface have been polished. Figure 4 The image shows the state after polishing with a slightly smaller radius (R) on the edge of the mounting surface; Figure 5 The image shows the ideal state after polishing, where the radius (R) of the edge of the mounting surface should be between R1.0 and R1.3. There should be no rolled edges or protrusions on the mounting surface. The rounded corner 22 must be precisely turned to the bottom of the slot to ensure that there are no sharp edges on the contact surface between the mounting surface 21 and the wafer 4. Otherwise, sharp edges will inevitably form rolled protrusions during the high-temperature polishing process, which will then rub against the silicon wafer and generate particles. The slot rod mounting surface supports the wafer as follows: Figure 6 As shown, chamfering tool 8 Figure 8 As shown; the machining path of chamfering tool 8 is as follows Figure 9 As shown; The wafer mounting surface of the slotted bar is subjected to flame polishing, which proceeds from the inside of the mounting surface outwards along the edges. Flame polishing transforms the originally whitish, frosted surface, caused by the damaged layer, into a transparent state at high temperatures. A transparent surface indicates that the damaged layer has been melted and completely removed. Flame polishing proceeds from the inside of the mounting surface outwards along the edges, with the wafer mounting surface... Figure 7 The flame polishing process is shown below. First, polish area one, then process areas two and three in sequence. Near the rounded corner edges, ensure that the flame impact force is from the inside out, so that the edge of the mounting surface is less likely to develop an inward bulge.

[0052] The grooving cutter is regularly repaired, with the cutter tip RX ground to the range of R0.2 to R0.5; the grinding angle F of the tool head is between 87° and 89°. Mechanical scratches and extrusion marks on the mounting surface of the grooved bar not only create a stepped feel but also increase the surface roughness. This increased roughness accelerates friction between the mounting surface and the wafer, generating particles during this process. Regularly adjusting the grooving cutter parameters helps to remove quartz powder during processing, preventing extrusion marks on the cutting surface, reducing friction between the mounting surface and the wafer, and minimizing particle generation. The machining of the grooved bar wafer mounting surface is as follows: Figure 10 As shown.

[0053] The quartz boat product undergoes flame polishing after fire-processing and welding. During the fire-processing and welding of the finished quartz boat, a cloud of mist is generated at the welded area. This mist is a white, opaque silica volatile substance adhering to the product surface. The mist is essentially particulate matter. Flame polishing can remove this surface mist, leaving the welded area mist as... Figure 11 As shown within the red box.

[0054] Fire polishing aims to achieve a transparent state for the product. After machining and grinding, quartz boat components develop a sub-damaged fracture layer on their surface. This fracture layer consists of granular material and has a whitish, matte finish. Figure 12 As shown within the red box; After the product is fully fire-polished, it becomes completely transparent. The transparent state of the product surface after fire-polishing is as follows: Figure 12 As shown within the green box; there is no residual broken layer on the product surface. A 500x microscopic photograph after fire polishing is shown below. Figure 13 As shown.

[0055] Example 1: All three slotted bars are machined uniformly: flatness 0.07, parallelism 0.06, and the edge chamfer of the mounting surface is R1.2; The blade tip radius is 0.3 mm, and the angle is 88°. High-temperature cleaning: 5 minutes each in the 98℃ cleaning tank (front and back) → 15 minutes in the 98℃ boiling tank → 1.5 minutes of rinsing; Hydrofluoric acid cleaning: Soak in 15% HF for 1 hour → Rinse for 1 minute → Pure water bath for 20 minutes → Rinse for 10 minutes; After welding, the entire surface is polished until transparent to remove any cloudiness. Final product cleaning: 10% nitric acid for 20 min → 5% HF for 120 min → multi-stage pure water rinse.

[0056] Comparative Example 1: The three grooved bars are processed in batches, and the edges of the mounting surface are not chamfered. They are cleaned and rinsed with a simple hot water method.

[0057] During the wafer fabrication process using the quartz boat manufactured in Comparative Example 1, dense-scale dot-like particles (such as...) appeared on the wafer surface. Figure 14 (Point-like particles). Component analysis shows the main components are O and Si (e.g., ...). Figure 15 (As shown in the analysis diagram). O mainly comes from quartz (SiO2), and Si mainly comes from quartz (SiO2) or wafers.

[0058] During the wafer fabrication process using the quartz boat manufactured in Example 1, individual point-like particles (such as...) on the wafer surface... Figure 16 (Point-like particles) or shows no particles at all.

[0059] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for solving the problem of particulate matter generation in quartz boats during wafer fabrication processes, characterized in that... This includes methods for treating pollution generated by the external environment and methods for treating pollution generated by the internal environment. Methods for treating pollution generated by the external environment include: methods for treating pollution generated by machining, methods for treating pollution generated by fire processing, and cleaning of the final product. Methods for treating pollution generated by the internal environment include completing the grooving of the three slotted bars required for a quartz boat in one clamping operation, and completing the grooving of the three slotted bars on the same mounting surface in one linear movement of the grooving cutter. After all three slots on the same mounting surface are grooved, the grooving of the next mounting surface continues.

2. The method for solving the problem of particulate matter generation in quartz boats during wafer fabrication processes according to claim 1, characterized in that, The grooving tool is regularly repaired, and the tool tip RX is ground to the range of R0.2 to R0.5; the grinding angle F of the tool grinding head is between 87° and 89°.

3. The method for solving the problem of particulate matter generation in quartz boats during wafer fabrication processes according to claim 2, characterized in that, The edges of the mounting surface of the slot bar should be rounded, and the radius R should be between R1.0 and R1.

3.

4. The method for solving the problem of particulate matter generation in quartz boats during wafer fabrication processes according to claim 3, characterized in that, The mounting surface of the grooved bar wafer is subjected to fire polishing, which proceeds from the inside of the mounting surface outwards along the edges.

5. A method for solving the problem of particulate matter generation in a quartz boat during wafer fabrication, as described in claim 4, characterized in that... Fire polishing is necessary to achieve a transparent state for the product.

6. A method for solving the problem of particulate matter generation in a quartz boat during wafer fabrication, as described in claim 5, characterized in that, After the quartz boat product has been flame-polished, the entire product is then flame-polished.

7. A method for solving the problem of particulate matter generation in a quartz boat during wafer fabrication, as described in claim 6, characterized in that, Methods for treating external environmental pollution from machining include first cleaning the parts at high temperature and then cleaning them with hydrofluoric acid after machining.

8. A method for solving the problem of particulate matter generation in a quartz boat during wafer fabrication, as described in claim 7, characterized in that, The high-temperature cleaning method is as follows: First, use a sponge dipped in degreasing solution to wipe the product surface, then rinse thoroughly with pure water to ensure that there is no degreasing solution residue on the surface. Next, immerse the product in a cleaning tank with a water temperature of 95℃ or higher for 5 minutes. After 5 minutes, turn the parts over and continue to soak for 5 minutes. After 10 minutes, take out the product, wipe the surface again with a sponge dipped in degreasing solution, and rinse thoroughly with pure water to ensure that there is no degreasing solution residue on the surface. Then, fill a boiling tank with pure water, heat the water temperature to above 95℃, and put the product into the boiling tank for 15 minutes of high-temperature boiling cleaning. After taking out the parts, rinse with pure water for more than 1 minute.

9. A method for solving the problem of particulate matter generation in a quartz boat during wafer fabrication, as described in claim 8, characterized in that, The hydrofluoric acid cleaning method is as follows: After rinsing with pure water, the parts are immersed in a 15% hydrofluoric acid bath for 1 hour to remove the broken layer on the surface of the product with a thickness of about 0.005mm to 0.02mm. After the hydrofluoric acid cleaning is completed, the parts are rinsed with pure water for more than 1 minute, and then the product is immersed in a pure water bath for 20 minutes. After that, the product is rinsed with pure water for another 10 minutes on a pure water rinsing table.

10. A method for solving the problem of particulate matter generation in a quartz boat during wafer fabrication, as described in claim 9, characterized in that... The final cleaning method is as follows: First, pour the degreasing solution onto a wiping cloth, then wipe the product surface, rinse with pure water for more than 1 minute to ensure that the cleaning solution is completely removed, then soak the product in a 10% nitric acid bath for 20 minutes, then rinse the product with pure water for more than 1 minute to ensure that the nitric acid is completely removed, finally soak the product in a 5% hydrofluoric acid bath for 120 minutes, after the hydrofluoric acid is removed, rinse with pure water for more than 1 minute, then soak in a pure water bath for 20 minutes, and finally place the product on a pure water rinsing platform for 3 minutes of pure water rinsing.

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