Wafer basket

Abstract

The application provides a wafer basket, comprising: a chamber, the chamber having a surrounding front wall, a first side wall, a second side wall, a back wall and a plurality of support parts, the chamber having an upper opening for arranging a plurality of wafers, the support parts being located at the bottom of the chamber for supporting the wafers; wherein the front wall has a first region and a second region which are connected from top to bottom and constitute an integral surface, the front wall has at least one first hollow region, and the second region is a region which is wide at the top and narrow at the bottom; the first side wall and the second side wall each have a plurality of second hollow regions, the first side wall is parallel to the second side wall, and the back wall has a plurality of third hollow regions. The basket adopts a local cutting process to optimize the structure, cuts a plurality of hollow regions, maximally reduces the contact area of the wafers and the basket, ensures that the acid liquid flows more uniformly when the wafers are soaked in the acid liquid, and then ensures the etching efficiency, improves the efficiency and ensures the recovery quality.

Description

Technical Field

[0001] This application relates to the field of semiconductor manufacturing, and more specifically, to a wafer basket. Background Technology

[0002] In semiconductor manufacturing processes, to ensure that production equipment is always in good working order, wafer fabs typically use dedicated monitor wafers to periodically monitor particulate contamination and film thickness uniformity on the equipment.

[0003] The efficiency of the wafer recycling process and the number of times it can be reused are key factors affecting the production cost control of wafer fabs. Currently, the basket-style processing method is commonly used for the recycling of monitored wafers.

[0004] However, the aforementioned method is prone to film residue at the contact area between the basket and the wafer, which can exacerbate particle contamination. Furthermore, extending the acid treatment time to improve the film removal effect may lead to excessive etching, increasing the surface roughness of the wafer and reducing its recyclability. In other words, existing technologies cannot significantly improve the wafer's cycle life while ensuring high recycling quality. Utility Model Content

[0005] The main objective of this application is to provide a wafer recycling basket to at least solve the problem that existing wafer recycling baskets can cause film residue on wafers or reduce wafer lifespan.

[0006] To achieve the above objectives, according to one aspect of this application, a wafer basket is provided, comprising: a chamber having an enclosing front wall, a first side wall, a second side wall, a rear wall, and a plurality of supporting portions; the chamber having an upper opening for arranging and placing a plurality of wafers; the supporting portions being located at the bottom of the chamber for supporting the wafers; wherein the front wall has a first region and a second region joined from top to bottom to form a single surface; the front wall has at least one first hollowed-out region; the second region is a region wider at the top and narrower at the bottom; both the first and second side walls have a plurality of second hollowed-out regions; the first side wall is parallel to the second side wall; and the rear wall has a plurality of third hollowed-out regions.

[0007] Optionally, both the first sidewall and the second sidewall have two second hollow areas from top to bottom, with a first crossbeam between the two second hollow areas. The surface of the first crossbeam facing the interior of the cavity has a plurality of first slots, which are used to fit with a portion of the edge area of ​​the wafer.

[0008] Optionally, each of the first slots has a plurality of bumps on the side surface near the front wall, the bumps contacting the wafer.

[0009] Optionally, the protrusion is a hemisphere, and the length of the first beam along a preset direction is greater than the product of the radius of the protrusion and the number of protrusions. The preset direction is the direction from the bottom edge of the front wall to the top edge of the front wall.

[0010] Optionally, there are two support portions, namely a first support portion and a second support portion. The first support portion is located in the region between the first inclined side of the second region of the front wall, the bottom edge of the first side wall, and the rear wall. The second support portion is located in the region between the second inclined side of the second region of the front wall, the bottom edge of the second side wall, and the rear wall. The first inclined side and the second inclined side of the second region are two opposite sides.

[0011] Optionally, the first support portion includes a plurality of second slots, and the second support portion includes a plurality of third slots, the second slots and the third slots being fitted to both sides of the vertically placed wafer.

[0012] Optionally, the edges of the first and second hollow areas are completely closed, while the edge of the third hollow area is not completely closed.

[0013] Optionally, the third hollow area has two parts, namely a first sub-area and a second sub-area. A second crossbeam is provided between the first sub-area and the second sub-area. The edge of the first sub-area has two sides and a bottom edge, forming the top opening of the rear wall. The edge of the second sub-area has two sides and a top edge, forming the bottom opening of the rear wall.

[0014] Optionally, the first sub-region is a trapezoidal region, and the second sub-region is a rectangular region.

[0015] Optionally, it further includes: at least one first support foot, the first support foot contacting the front wall, the first side wall and the rear wall respectively; at least one second support foot, the second support foot contacting the front wall, the second side wall and the rear wall respectively, the first support foot and the second support foot being used to support the chamber.

[0016] The wafer recycling basket of this application includes: a chamber having an enclosed front wall, a first side wall, a second side wall, a rear wall, and multiple support portions; the chamber has an opening at the top for arranging multiple wafers; and the support portions are located at the bottom of the chamber for supporting the wafers. The front wall has a first region and a second region joined from top to bottom to form a single surface, and the front wall has at least one first hollowed-out region. The second region is wider at the top and narrower at the bottom. Both the first and second side walls have multiple second hollowed-out regions, with the first and second side walls parallel to each other. The rear wall has multiple third hollowed-out regions. This basket uses a local cutting process to optimize its structure, cutting out multiple hollowed-out regions to minimize the contact area between the wafer and the basket. This ensures more uniform acid flow during wafer immersion in acid, thereby guaranteeing etching efficiency. This improves efficiency while ensuring recycling quality, solving the problem in existing wafer recycling baskets that lead to residual film on the wafer or reduced wafer lifespan. Attached Figure Description

[0017] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0018] Figure 1 A schematic diagram of the structure of a wafer basket provided in an embodiment of this application is shown;

[0019] Figure 2 A front view of a wafer basket provided in an embodiment of this application is shown;

[0020] Figure 3 A side view of a wafer basket provided in an embodiment of this application is shown;

[0021] Figure 4 A partial top view of a wafer basket provided in an embodiment of this application is shown;

[0022] Figure 5 A rear view of a wafer basket provided in an embodiment of this application is shown;

[0023] Figure 6 A comparison diagram is shown of wafer patterns prepared using the basket fabrication method of the prior art and wafer patterns prepared using the wafer basket fabrication method of this application.

[0024] Figure 7 The initial recovery rate data of wafers prepared using the wafer basket of this application are shown;

[0025] Figure 8 The data on the recycling lifetime and recycling quality of wafers prepared using the wafer basket of this application are shown.

[0026] The above figures include the following reference numerals:

[0027] 1. Chamber; 2. Front wall; 21. First region; 22. Second region; 23. First hollowed-out region; 3. First side wall; 31. Second hollowed-out region; 311. First slot; 32. First crossbeam; 322. Protrusion; 4. Second side wall; 5. Rear wall; 51. Third hollowed-out region; 511. First sub-region; 512. Second sub-region; 513. Second crossbeam; 6. Support part; 61. First support part; 611. Second slot; 62. Second support part; 621. Third slot; 7. First support foot; 8. Second support foot. Detailed Implementation

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0031] As described in the background section, in existing technologies, the large contact area between the wafer and the basket makes it prone to film residue in the contact area, thus exacerbating particle contamination. Furthermore, extending the acid treatment time to improve the film removal effect may lead to excessive etching, increasing the surface roughness of the wafer and reducing its recyclability. Moreover, existing technologies cannot significantly improve the wafer's cycle life while ensuring high recycling quality.

[0032] Based on current semiconductor manufacturing technology node classification standards, monitored wafer recycling processes can be divided into two categories: 6-inch and above, and 6-inch and below. For 6-inch and above wafers, a basketless recycling scheme is generally used, and its recycling effect basically meets process requirements. However, for 6-inch and below wafers, due to current technological limitations, a basket recycling method is still required, resulting in poor recycling performance in the wafer-basket contact area. Furthermore, the current integrated stripping and particle removal process menu suffers from a low number of reuse cycles, which significantly impacts wafer foundry cost control.

[0033] In existing 6-inch and smaller wafer recycling systems, the contact area between the basket and the wafer is too large, meaning that the front and side walls are solid structures without any open areas. This leads to the following technical defects in the contact area between the basket carrier and the wafer: 1. The excessively large geometric contact surface easily leads to residue accumulation; 2. The traditional U-shaped groove structure creates fluid dead zones, generating eddy currents during the cleaning process, resulting in less than ideal cleaning results; 3. Increasing the amount of over-etching or the number of cleaning cycles can improve recycling quality, but it will greatly reduce the recycling lifespan. Excessive etching and cleaning will cause changes in the surface structure quality of the wafer.

[0034] To address the problem that existing wafer recycling baskets can lead to residual film layers on wafers or reduce their lifespan, embodiments of this application provide a wafer recycling basket.

[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0036] This embodiment provides a wafer basket, such as Figure 1 , Figure 2 and Figure 3 As shown, the device includes: a chamber 1, which has an enclosed front wall 2, a first side wall 3, a second side wall 4, a rear wall 5, and multiple support portions 6. The chamber 1 has an opening at the top for arranging multiple wafers, and the support portions 6 are located at the bottom of the chamber 1 for supporting the wafers. The front wall 2 has a first region 21 and a second region 22 joined from top to bottom to form a whole surface. The front wall 2 has at least one first hollow region 23. The bottom edge length of the first region 21 is the same as the top edge length of the second region 22. The second region 22 is a region that is wider at the top and narrower at the bottom. The first side wall 3 and the second side wall 4 each have multiple second hollow regions 31. The first side wall 3 is parallel to the second side wall 4. The rear wall 5 has multiple third hollow regions 51.

[0037] The wafer basket is designed with multiple slots to hold and secure wafers, ensuring their safe and stable transport during cleaning and handling, preventing displacement or damage. The chamber is the core of the basket, used to house and arrange multiple wafers. The front wall, first side wall, second side wall, and rear wall form the four walls of the chamber, creating a stable framework that supports the wafers and defines their arrangement. The front wall is located at the front end in the wafer placement direction, the first and second side walls are located on either side of the chamber, and the rear wall is located at the rear end in the wafer placement direction.

[0038] It's important to clarify that the first and second regions are a single entity, meaning a single surface is divided into these two regions. The second region is wider at the top and narrower at the bottom; this shape helps stabilize the wafer within the basket while reducing the contact area between the wafer and the basket, thus minimizing dead zones during cleaning. Multiple support sections are located inside the chamber to directly support the wafer, ensuring its stability during processing. The design of these support sections must consider the wafer's size and weight, as well as ensure its safety during cleaning, handling, and drying.

[0039] In some specific implementations, the first region 21 is a rectangular region and the second region 22 is a trapezoidal region.

[0040] Specifically, the rectangular first region 21 and the trapezoidal second region 22 provide different hydrodynamic environments. The right-angled sides of the rectangular region help the cleaning fluid or acid flow smoothly and in a straight line, reducing fluid stagnation in the right-angled areas, thereby improving the uniformity and efficiency of cleaning. The inclined sides of the trapezoidal region guide the fluid downwards along the slope, preventing eddies or stagnation at sharp corners, ensuring the cleaning fluid fully covers the wafer surface, and reducing cleaning dead zones. The combined structure of the first region 21 and the second region 22 provides more stable support for the wafer. The rectangular region serves as the main support surface for the wafer, providing a solid base; while the trapezoidal region, by adjusting the contact angle and area size, adapts to wafers of different sizes or shapes, ensuring precise positioning of the wafer during the cleaning process, preventing wafer movement or tilting, and improving the safety and accuracy of wafer processing.

[0041] The first hollowed-out area 23, the second hollowed-out area 31, and the third hollowed-out area 51 are all designed to reduce the contact area between the wafer and the basket. Therefore, in this embodiment, the number, size, shape, and position of the three hollowed-out areas are not specifically limited and can be adjusted according to actual needs. The second area 22, which is wider at the top and narrower at the bottom, can better support the wafer and prevent it from falling.

[0042] The determination of the cut dimensions for the hollowed-out area is based on the results obtained through multiple cutting experiments while ensuring the optimal contact area. A basket-wafer contact model is established using a topology optimization algorithm: Ac = k·((Tw·ρw) / Dw), where Ac is the optimal contact area, Tw is the wafer thickness, ρw is the material density, Dw is the wafer diameter, and k is the wafer shape factor (typically 0.38–0.42). The complexity of the K value lies in its integration of the triple influence of material, structure, and operating conditions. The range of 0.38–0.42 is actually an empirical value for typical silicon wafers, calculated based on historical data.

[0043] The aforementioned wafer basket has removed the area on the front that obstructs the wafer (i.e., the first cutout area 23), but still retains the CST (Wafer Carrier System) numbering area, and removes the areas on both sides of the CST that are in contact with the wafer, while retaining the position that supports the wafer and the position that is in contact during wafer transport.

[0044] The wafer recycling basket of this application includes: a chamber having an enclosed front wall, a first side wall, a second side wall, a rear wall, and multiple support portions; the chamber has an opening at the top for arranging multiple wafers; and the support portions are located at the bottom of the chamber for supporting the wafers. The front wall has a first region and a second region joined from top to bottom to form a single surface. The first region has at least one first hollowed-out area, and the second region is wider at the top and narrower at the bottom. Both the first and second side walls have multiple second hollowed-out areas, with the first and second side walls parallel to each other. The rear wall has multiple third hollowed-out areas. This basket utilizes a local cutting process to optimize its structure, cutting out multiple hollowed-out areas to minimize the contact area between the wafer and the basket. This ensures more uniform acid flow during immersion in acid, thereby guaranteeing etching efficiency and improving both efficiency and recycling quality. This solves the problem in existing wafer recycling baskets that can lead to residual film on the wafer or reduced wafer lifespan.

[0045] Using the above-mentioned baskets can ensure that there is no film residue or particulate contamination on the wafer surface, thereby increasing the recycling qualification rate to over 85%. While maintaining a recycling qualification rate of no less than 60%, the number of wafers can be recycled from the original 2-3 times to at least 5 times, thereby significantly reducing the production cost of wafer fabs.

[0046] The above embodiments minimize the contact area of ​​the wafer tray and improve upon the traditional wafer tray structure. While ensuring stable wafer transport and preventing misalignment during the drying process, a local cutting process optimizes the wafer tray slot structure, minimizing the contact area between the wafer and the tray. Simultaneously, raised small dots are added to the contact area of ​​the slot at the edge, reducing the risk of film residue. The wafer tray is supported by two vertical fixing strips, with slots on the inner side of the strips for placing the wafer. The slot positions of the tray are used to isolate wafer slabs to prevent contamination. By cutting and optimizing the shape of the wafer tray, the contact area between the wafer and the slots is reduced, ensuring more uniform acid flow during wafer immersion in acid, thereby ensuring etching efficiency and improving recovery quality. Optimization of recovery quality is achieved through precise control of the wafer tray shape.

[0047] This can significantly improve the quality and efficiency of recycling. Compared with traditional methods, the residual film and particulate contamination on the wafer surface are greatly reduced, and the recycling qualification rate is significantly improved (some wafer fabs can avoid this by relying on excessive etching time and the additional cost of secondary cleaning).

[0048] Extending cycle life and reducing production costs: By optimizing acid reaction time and basket structure, the surface roughness of wafers is reduced, increasing the number of cycles from the original 2-3 times to at least 5 times, while maintaining a recycling qualification rate of over 60%, effectively reducing the operating costs of wafer fabs.

[0049] By modifying and optimizing the shape of the flower basket, the recycling efficiency of wafers can be significantly improved while ensuring high recycling quality.

[0050] The basket contact area minimization design improves the traditional basket structure. While ensuring stable wafer transport and preventing misalignment during the drying process, the basket slot structure is optimized using a local cutting process to minimize the contact area between the wafer and the basket.

[0051] Figure 2 This is a front view of a wafer basket provided in an embodiment of this application, such as... Figure 2 As shown, the first hollow area 23 can be a square structure with a side length ranging from 75mm to 85mm, preferably 80mm.

[0052] In some embodiments, such as Figure 3 As shown, both the first sidewall 3 and the second sidewall have two second hollowed-out areas 31 from top to bottom. A first crossbeam 32 is located between the two second hollowed-out areas 31. The surface of the first crossbeam 32 facing the interior of the cavity has multiple first slots. The first slots are used to fit with a portion of the edge area of ​​the wafer. The cross-section formed by cutting the first slot along a cutting surface perpendicular to the first sidewall 3 has a first preset shape.

[0053] The first preset shape can be V-shaped, rectangular, or elliptical, etc. If it is rectangular, its edges can be smooth curves. This application preferably uses a rectangular shape, i.e., as shown in the figure. Figure 3 and Figure 4 As shown.

[0054] Since the second sidewall has the same structure as the first sidewall, therefore Figure 3 Only the first sidewall is used as an example. Figure 3 The width of the first crossbeam 32 is in the range of 7mm to 9mm, preferably 8mm.

[0055] Specifically, the first slot has a serrated structure, and the presence of the second hollow area 31 allows the cleaning fluid or airflow to pass more freely through the sidewalls and reach all sides of the wafer, thereby improving the uniformity and efficiency of cleaning. The first slot 311 with a first preset cross-section further optimizes the fluid path, allowing the fluid to better cover the wafer's support points when passing through the slot, reducing cleaning blind spots and ensuring comprehensive cleaning of the wafer surface. The presence of the first crossbeam 32 enhances the structural stability of the sidewalls, preventing deformation of the sidewalls under long-term use or high temperature and pressure environments. The first slot 311 with a first preset shape supports the wafer while reducing the actual contact area, which means reduced friction between the wafer and the basket, lowering the risk of scratches or damage to the wafer during processing.

[0056] By reducing the direct contact area between the wafer and the basket and improving fluid coverage, this design significantly reduces the amount of chemicals or particulate matter remaining on the wafer surface during cleaning. The shape of the first pre-defined slot also helps the liquid flow away better, reducing liquid stagnation and thus lowering the possibility of secondary contamination. The design of the first slot 311 is not limited to improvements in fluid dynamics; it also helps to more accurately position and hold the wafer, preventing displacement or misalignment during processing and ensuring that each wafer receives consistent and high-quality processing.

[0057] In some specific embodiments, the data is substituted into the formula for calculation. The result is: Ac = 0.38 × ((380 × 2.33 × 1000) / 150)) = 22.43 mm 2 The wafer diameter is 150mm, the basket diameter is 153mm, and the serration depth of the contact between the basket and the wafer is approximately 12mm. The normal contact area between the wafer and the basket is 3.14 × (75 × 75 - 63 × 63) × 2 / 3 = 34.67mm². 2The front side is not considered the contact area, so the cutting area on the front side is cut while ensuring the coding. The cutting areas on the left and right sides are cut while ensuring the corner positions of the lower support points. The cutting pattern was finally determined after multiple wafer push tests and multiple recycling tests.

[0058] In some embodiments, such as Figure 4 As shown, each of the first slots 311 has a plurality of protrusions 322 on the side surface near the front wall 2, and the protrusions 322 are in contact with the wafer.

[0059] The addition of raised dots at the edge of the slot contact area reduces the risk of film residue. By incorporating bumps 322 on the contact surface between the wafer and the basket, the direct contact area between the wafer and the basket is significantly reduced. This reduces cleaning dead zones created by the wafer surface contacting the basket during cleaning, facilitating more thorough removal of residues and improving cleaning efficiency and quality. The bump design alters the flow pattern of fluids (such as cleaning solution) on the wafer surface, preventing eddies at the wafer-basket contact point and thus avoiding particle redeposition, ensuring wafer surface cleanliness. Bumps 322 guide the fluid to form a more uniform flow path around them, improving cleaning effectiveness. The presence of bumps 322 also helps to fix the wafer, preventing displacement due to vibration or fluid scouring during cleaning, contributing to wafer stability and safety throughout the process and preventing damage caused by wafer misalignment. Reducing film residue and particle contamination on the wafer surface also means increasing wafer recovery rate. After cleaning and processing, the cleanliness of the wafer surface directly affects its reusability. The 322 bump design helps ensure that the wafer meets the standards for high recyclability. While ensuring wafer surface cleanliness, the 322 bump design also helps control changes in the microstructure of the wafer surface, avoiding increased surface roughness due to excessively large contact areas, thereby extending the number of wafers that can be recycled.

[0060] In some embodiments, the protrusion is a hemisphere, and the length of the first crossbeam along a predetermined direction is greater than the product of the radius of the protrusion and the number of protrusions.

[0061] The length of the first crossbeam along the preset direction ranges from 8mm to 12mm, preferably 10mm, and the radius of the protrusions ranges from 0.8mm to 1.2mm, preferably 1mm. The preset direction is from the bottom edge of the front wall to the top edge of the front wall. The length design of the first crossbeam takes into account the size and number of protrusions, which allows the equipment to maintain good support and cleaning effect when processing wafers of different sizes or thicknesses, enhancing the adaptability of the basket structure to various wafer specifications and improving the versatility and flexibility of the equipment. When the length of the first crossbeam exceeds a preset threshold (the product of the protrusion radius and the number), the fluid can be more evenly distributed on the wafer surface when passing through the gaps between these protrusions. By rationally planning the length of the first crossbeam, the structural strength reduction caused by excessive protrusion density is avoided. The appropriate distance not only maintains the stability of the crossbeam but also reduces wear caused by wafer friction or cleaning fluid erosion during long-term use, extending the service life of the basket structure.

[0062] Specifically, the hemispherical bumps reduce the resistance of fluids (such as acids or cleaning solutions) as they pass through the first slot. Compared to sharp angles or planar contacts, the hemispherical bumps more effectively guide the fluid around the contact point between the wafer and the basket, reducing dead zones and eddies, thereby improving the uniform distribution of the cleaning solution on the wafer surface and enhancing cleaning efficiency and effectiveness. The first crossbeam is 10mm long, ensuring sufficient structural strength while providing stable support for the wafer. The hemispherical bumps precisely position the wafer, preventing displacement due to fluid impact or vibration during cleaning, maintaining the wafer's stability and correct position in the basket, and avoiding damage during processing or handling. This reduces film residue and particulate contamination, improves the wafer cleaning pass rate, significantly extends the wafer's reusability, reduces wafer replacement frequency, and saves on wafer fab production costs. The design of hemispherical bumps can prevent changes in the microstructure of the wafer surface caused by prolonged contact with a hard plane, such as an increase in surface roughness. This maintains the smoothness of the wafer surface and ensures that the wafer can maintain good process performance after multiple cycles of use.

[0063] In some embodiments, such as Figure 1 , Figure 2 As shown, there are two support parts 6, namely a first support part 61 and a second support part 62. The first support part 61 is located in the area between the first inclined side of the second region 22 of the front wall 2, the bottom edge of the first side wall 3 and the rear wall 5. The second support part 62 is located in the area between the second inclined side of the second region 22 of the front wall 2, the bottom edge of the second side wall 4 and the rear wall 5. The first inclined side and the second inclined side of the second region 22 are two opposite sides.

[0064] The support portion 6 is designed as two independent parts: a first support portion 61 and a second support portion 62. The first support portion 61 and the second support portion 62 are located on the first and second inclined sides of the second region 22 of the front wall 2, and in the area between the bottom edge of the first sidewall 3 and the second sidewall 4 and the rear wall 5. This layout ensures precise support and positioning of the wafer in the basket, preventing displacement of the wafer due to fluid impact or vibration during cleaning, maintaining wafer stability, and thus improving cleaning efficiency and wafer recovery quality. The support portion 6 is divided into two parts, each contacting only a specific area of ​​the wafer. Compared to integral or dense support structures, this design reduces the total contact area between the wafer and the support portion, lowering the risk of uneven cleaning fluid coverage or cleaning dead zones, and helping to more thoroughly remove residues from the wafer surface, improving cleaning efficiency. The first support portion 61 and the second support portion 62 are located in opposing inclined side regions; this design helps optimize hydrodynamic characteristics. During the cleaning process, the cleaning fluid can flow more freely between the wafer and the support, reducing fluid resistance and preventing eddy currents. This improves the uniform distribution of the cleaning fluid on the wafer surface, ensuring thorough cleaning. Dividing the support into two independent parts, located on the sloping side and the bottom edge of the sidewall of the basket respectively, provides sufficient mechanical strength to ensure the safety and stability of the wafer during processing, while reducing the overall weight for easier handling and transport.

[0065] In some embodiments, such as Figure 1 and Figure 2 As shown, the first support portion 61 includes a plurality of second slots 611, and the second support portion 62 includes a plurality of third slots 621. The second slots 611 and the third slots 621 are attached to the two sides of the vertically placed wafer.

[0066] Multiple second slots 611 and third slots 621 are tightly fitted to the sides of different wafers, providing precise support and positioning. This design ensures wafer stability when placed vertically, reduces the probability of wafer displacement during cleaning or stripping processes, and prevents wafer damage or uneven cleaning due to instability. The slot-wafer fit reduces fluid resistance on both sides of the wafer, promoting uniform fluid flow. Especially during wafer cleaning, the fluid can smoothly pass through both sides of the wafer, improving fluid dynamics, thereby enhancing the coverage and penetration of the cleaning solution on the wafer surface, reducing surface residue, and improving recycling efficiency and quality. The precise fit between the slots and the wafer edges reduces direct contact pressure between the wafer edges and the support, reducing wear or cracks caused by physical contact at the wafer edges, and extending the number of wafer cycles. In wafer recycling processes, edge damage is one of the key factors affecting wafer reuse; therefore, this design is crucial for improving wafer lifespan.

[0067] In some specific embodiments, the second slot 611 is used to fit with the first region of the wafer, and the third slot 621 is used to fit with the second region of the wafer. The first region and the second region are two regions symmetrical about the central axis of the wafer.

[0068] By attaching the second and third slots to the first and second regions of the wafer respectively and symmetrically arranging them along the central axis, balanced support is achieved for the wafer during cleaning and recycling processes. This design ensures that the wafer will not tilt, misalign, or be damaged at any stage of operation due to excessive support on one side, which is especially critical when handling thin or fragile wafers. The symmetrical design improves the consistency of process handling and reduces the differences in processing effects between different wafer locations and batches. This means that regardless of which side or position the wafer is placed on, it receives similar cleaning conditions, which helps to standardize wafer recycling quality standards and improve the yield of the entire production line.

[0069] The cross-section formed by cutting the second slot 611 along the cutting surface perpendicular to the first inclined side of the second region 22 of the front wall 2 is a second preset shape, and the cross-section formed by cutting the third slot 621 along the cutting surface perpendicular to the second inclined side of the second region 22 of the front wall 2 is a second preset shape.

[0070] The second preset shape can be a V-shape, a rectangle, or an ellipse, etc. If it is a rectangle, its edges can be smooth curves. This application prefers the shape of a rectangle.

[0071] The third slot can be a serrated structure. By adopting a symmetrical toothed support structure, the contact area is reduced to a maximum of about 50% (compared to the traditional basket) while ensuring that the wafer does not misalign during transport and machine operation. The cross-sectional area of ​​the fluid channel is increased, and the stress concentration factor is reduced.

[0072] The V-shaped cross-section of the second slot 611 and the third slot 621 better guides the distribution of fluid (such as cleaning fluid or acid) between the wafer and the support. The V-shaped design helps the fluid cover the support area of ​​the wafer more evenly, reducing the possibility of eddies or dead zones in these areas, thereby improving the uniformity and efficiency of wafer cleaning. The V-shaped slot design reduces the contact area between the wafer and the support, preventing excessive contact between the wafer edge and the hard surface during cleaning, reducing micro-morphological changes on the wafer surface, such as increased roughness, and thus lowering the risk of wafer surface damage. The V-shaped cross-section of the second slot 611 and the third slot 621 allows for more precise wafer positioning, especially in the edge areas. This design contributes to wafer stability during processing, preventing wafer misalignment or slippage, and improving the safety and efficiency of wafer processing.

[0073] In some embodiments, such as Figure 1 and Figure 3 As shown, the edges of the first and second hollow areas are completely closed, while the edge of the third hollow area is not completely closed.

[0074] The edges of both the first and second hollow areas are completely closed, effectively controlling the flow path of fluids (such as cleaning fluid or acid) within the basket. This prevents unnecessary eddies and dead zones from forming at the wafer edges, improving the uniformity of fluid coverage and cleaning efficiency. The third hollow area 51, with its partially closed edges, facilitates rapid fluid discharge and replenishment, ensuring a high fluid turnover rate within the chamber and thus enhancing the cleaning effect. The partially closed design of the third hollow area 51 also promotes rapid circulation of the cleaning fluid, improving its utilization efficiency and recycling rate, thereby reducing chemical consumption and wastewater treatment costs.

[0075] In some embodiments, such as Figure 5 As shown, there are two third hollow areas, namely the first sub-area 511 and the second sub-area 512. A second crossbeam 513 is provided between the first sub-area 511 and the second sub-area 512. The edge of the first sub-area 511 has two sides and a bottom edge, forming the top opening of the rear wall. The edge of the second sub-area 512 has two sides and a top edge, forming the bottom opening of the rear wall.

[0076] Specifically, the first sub-region 511 is used to allow liquid to flow into the chamber, and the second sub-region 512 is used to allow the liquid to flow out of the chamber. The liquid is used to clean the wafer.

[0077] The design of the first sub-region 511 and the second sub-region 512 allows fluid to enter and exit from two opposite directions, thus forming a bidirectional fluid circulation path. This helps the fluid to cover the wafer surface more evenly during the cleaning process, improving cleaning efficiency and wafer surface cleanliness. Because the fluid can flow from both directions, the possibility of dead zones forming near wafer edges or supports is reduced, ensuring full coverage of the cleaning solution on the wafer surface and reducing film residue and particulate contamination.

[0078] The presence of the second crossbeam 513 not only enhances the overall structural strength of the basket but also positions and supports the wafer, ensuring its stability during the cleaning process and preventing wafer displacement or damage caused by fluid impact or vibration. The design of the second crossbeam 513 not only aids in wafer positioning but also enhances the structural strength and durability of the basket, enabling it to maintain good performance in long-term use and complex cleaning environments.

[0079] In some embodiments, the first sub-region 511 is a trapezoidal region, and the second sub-region 512 is a rectangular region. The trapezoidal region design guides the fluid to form a more effective rinsing pattern. When the fluid enters the trapezoidal region, its gradually expanding shape promotes uniform fluid diffusion, reduces the concentration of fluid impact force, and avoids localized wear on the wafer surface, thereby improving cleaning efficiency and wafer recovery quality. The trapezoidal region can disperse the stress generated during wafer placement or removal. Compared to a rectangular region with straight edges, the sloping sides of the trapezoid can more naturally adapt to the placement pressure of the wafer, reducing the direct stress on the wafer edges, lowering the risk of wafer breakage or cracking, and extending the number of wafer cycles. The rectangular region provides a stable support surface, especially when the wafer is inserted or removed. The quadrilateral structure provides stable positioning for the wafer, preventing it from shaking or shifting during operation, ensuring the mechanical stability of the wafer during cleaning, and reducing damage caused by improper operation. The combined design of the first and second sub-regions helps improve the cleaning consistency of the wafer in different locations. The combination of the fluid guiding effect of the trapezoidal region and the stabilizing support effect of the rectangular region ensures that a similar cleaning effect can be obtained regardless of the position of the wafer in the basket, thus improving the process consistency of the entire batch of wafers.

[0080] In addition, the slope of the trapezoidal region can effectively reduce the deposition of residues. The fluid flows more smoothly on the trapezoidal slope, reducing the chance of solid particles remaining at the edges, lowering the risk of film residue, making the wafer surface cleaner, and improving the recycling yield.

[0081] In some embodiments, the system further includes: at least one first support leg 7, which contacts the front wall 2, the first side wall 3, and the rear wall 5 respectively; and at least one second support leg 8, which contacts the front wall 2, the second side wall 4, and the rear wall 5 respectively, wherein the first support leg 7 and the second support leg 8 are used to support the chamber 1.

[0082] Specifically, the placement of the first support foot 7 and the second support foot 8 increases the contact points between the basket and the cleaning chamber, providing additional support and enhancing the overall structural stability of the basket and chamber. This helps maintain the stability of the basket and chamber during the cleaning process, even under high temperature, high pressure, or highly corrosive environments, reducing the risk of wafer damage due to structural instability. The design of the support feet helps control the vibration and displacement of the basket during the cleaning process, ensuring the wafer remains in a stable position within the basket. During cleaning or etching, even minor vibrations or displacements can lead to uneven surface treatment or even damage to the wafer. By adding support feet, vibration can be controlled more effectively, improving the accuracy and quality of wafer processing. The arrangement of the support feet optimizes the flow characteristics of fluid within the chamber. They not only support the chamber but also act as obstacles to fluid flow, helping to guide the fluid along a more efficient path and reducing fluid accumulation at the bottom of the chamber, thereby improving the wafer cleaning effect.

[0083] The above embodiments reduce large-area contamination by reducing the contact area, increase the smooth small bumps on both sides of the slot in the direction of contact with the wafer, and reduce the impact of liquid pressure on the wafer contact surface; ultimately, the wafer regeneration qualification rate reaches more than 95%, the number of recycling cycles is extended from 2-3 times to 6-8 times, and the recycling rate is maintained at more than 60%, which greatly reduces the production cost of wafer fabs.

[0084] In existing technologies, before wafers can be reused, they are placed in an acid solution using a basket as a carrier for etching and cleaning. The basket typically has 25 slots, and the wafer is placed vertically into the corresponding slot. When the wafer is placed in the basket and enters the acid solution, the acid flows into the basket. Because the wafer contacts the side of the basket, the acid flow is obstructed, often resulting in residue at the contact points between the wafer and the slots. This means there is a certain depth of contact between the basket and the wafer edge, creating cleaning dead zones, especially on the wafer closest to the front of the basket (the 25th wafer). Not only the wafer edge, but the entire front of the wafer often has residue, meaning the entire surface of the wafer in contact with the basket is not effectively recycled, affecting the monitoring of wafer reuse and increasing production costs. To solve these problems, a new type of wafer recycling basket is proposed by optimizing the structure of the existing basket. Its structure is as follows: Figure 1 As shown, the flower basket is designed to maximize the area of ​​the front and side support strips, forming a first and second hollowed-out area. A first crossbeam between the two second hollowed-out areas is used to place and fix the wafer during the pushing process. Simultaneously, a smooth small bump (such as...) is prepared in the middle of the first slot of the first crossbeam. Figure 4 In acidic solutions, the wafer is subjected to water pressure, which further reduces the contact area between the wafer front and the basket when the wafer front comes into contact with the basket.

[0085] like Figure 6 As shown, Figure 6 (a) A pattern of the 25th wafer prepared using a basket fabrication technique. Figure 6 (b) Patterns of other wafers prepared using existing basket fabrication techniques. Figure 6 (c) A diagram of a wafer fabricated using the basket of this application. The red areas in the diagram represent wafer residue. It can be seen that the 25th wafer fabricated using the existing basket (i.e., the wafer closest to the basket's front surface) often has residue not only at the wafer edge but also across the entire front surface. This indicates poor overall recycling of the wafer surface in contact with the basket, affecting the monitoring of wafer reuse. Other wafers fabricated using the existing basket also have large areas of residue at their edges. However, wafers fabricated using the basket of this application have very little residue, improving wafer lifespan.

[0086] The aforementioned wafer basket minimizes the contact area between the wafer and the basket to reduce recycling residue caused by contact. Simultaneously, the contact points on both sides maintain a symmetrical shape to ensure that the liquid flow on both sides does not conflict during acid tank recycling, guaranteeing uniform corrosion. Since the wafer is pushed and conveyed parallel to the ground, a first crossbeam (maximizing the conveying distance) is added between the basket opening and the bottom to prevent the wafer from tilting downwards due to its own weight and getting stuck in the slot at the bottom of the basket. Additionally, a small, smooth protrusion is welded into the first slot of the first crossbeam, reducing the contact area between the basket and the wafer's front side. This minimizes the impact of water pressure on the wafer's front side in the liquid, preventing corrosion and cleaning defects at specific points.

[0087] In the above scheme, by optimizing the contact area between the basket and the wafer and adding smooth raised small dots, the morphology is optimized based on the existing recycling basket's basic structure. In the film removal process, the influence of the contact surface on the etching liquid and the influence of the shielding surface on the nearest wafer surface are reduced. The addition of small dot structure reduces the impact of liquid pressure on the wafer's front-side process.

[0088] Verification of Equipment Modification Results: To quantitatively evaluate the performance of the improved basket, a comparative experiment was conducted. The test group consisted of the modified basket of this application, while the control group consisted of the existing technology basket. Mechanical stability testing was performed on the modified basket: a marathon test was conducted during wafer transfer, with 100 repeated transfers using the modified basket. No wafer misalignment or scratching occurred. Furthermore, the modified basket's structural shape was measured after 300 cycles of use, and the deformation was <15μm (within the controllable range). The modified basket design significantly improved contact contamination and contact point residue issues.

[0089] The verification results are as follows Figure 7 and Figure 8 As shown, Figure 7 The horizontal axis represents the batch of wafer samples, with each batch containing 25 wafers. Figure 7 The vertical axis represents the initial recovery rate of each batch of wafers. Figure 8 The horizontal axis represents the batch of wafer samples, with each batch containing 25 wafers. Figure 8 The left vertical axis represents the number of times each batch of wafers was recycled, and the right vertical axis represents the recycling rate of each batch of wafers corresponding to the number of recycling times on the left. Due to the reduced contact area, the improved basket reduces the area of ​​residual patterns on the wafer surface by more than 50%, maintaining an initial wafer recycling rate of over 95%. The number of wafer recycling cycles is generally between 6 and 8, with the recycling rate remaining above 50% even after 6 cycles. This significantly improves the quality and number of recycling cycles, ensuring both quality and quantity, thus reducing the production costs of the wafer fab. Compared to traditional recycling methods, the above embodiment not only ensures recycling quality but also avoids the problems of multiple cleanings and excessive corrosion. While ensuring recycling efficiency, it also greatly increases the number of recycling cycles, effectively reducing the cost of monitoring wafers during the wafer fab's production process.

[0090] The above embodiments, through optimization of recycling equipment and processes, significantly improve the quality and number of wafer recycling cycles, ensuring both quality and quantity, thereby reducing the production costs of wafer fabs. Compared to traditional recycling methods, this embodiment not only guarantees recycling quality (the initial recovery rate is generally maintained above 95%), but also avoids the problems of multiple cleanings and excessive corrosion. While ensuring recycling efficiency, it also greatly increases the number of recycling cycles (wafers are generally recycled 6-8 times, and the recovery rate remains above 50% even after 6 cycles), effectively reducing the cost of monitoring wafers during wafer fab production.

[0091] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0092] It should also be noted that 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 process, method, article, or apparatus. Unless otherwise specified, 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.

[0093] As can be seen from the above description, the embodiments of this application achieve the following technical effects:

[0094] The wafer recycling basket of this application includes: a chamber having a front wall, a first side wall, a second side wall, a rear wall, and multiple support portions. The chamber is used to arrange and place multiple wafers, and the support portions are used to support the wafers. The front wall has a first region and a second region from top to bottom, and at least one first hollowed-out region. The bottom edge length of the first region is the same as the top edge length of the second region, and the second region is wider at the top and narrower at the bottom. Both the first and second side walls have multiple second hollowed-out regions, with the first and second side walls parallel to each other. The rear wall has multiple third hollowed-out regions. This basket uses a local cutting process to optimize its structure, cutting out multiple hollowed-out regions to minimize the contact area between the wafer and the basket. This ensures more uniform acid flow during wafer immersion in acid, thereby guaranteeing etching efficiency. While improving efficiency, it also ensures recycling quality, solving the problem that existing wafer recycling baskets can lead to residual film on the wafer or reduced wafer lifespan.

[0095] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A wafer flower basket, characterized in that, include: A chamber having an enclosed front wall, a first side wall, a second side wall, a rear wall, and multiple support portions; the chamber has an upper opening for arranging multiple wafers; and the support portions are located at the bottom of the chamber for supporting the wafers. The front wall has a first region and a second region joined from top to bottom to form a whole surface. The front wall has at least one first hollowed-out region, and the second region is a region that is wider at the top and narrower at the bottom. Both the first sidewall and the second sidewall have multiple second hollow areas, the first sidewall is parallel to the second sidewall, and the rear wall has multiple third hollow areas.

2. The wafer basket according to claim 1, characterized in that, Both the first sidewall and the second sidewall have two second hollow areas from top to bottom, and a first crossbeam is provided between the two second hollow areas. The surface of the first crossbeam facing the interior of the cavity has a plurality of first slots, and the first slots are used to fit with a portion of the edge area of ​​the wafer.

3. The wafer basket according to claim 2, characterized in that, Each of the first slots has a plurality of bumps on the side surface near the front wall, and the bumps are in contact with the wafer.

4. The wafer basket according to claim 3, characterized in that, The protrusion is a hemisphere, and the length of the first beam along a preset direction is greater than the product of the radius of the protrusion and the number of protrusions. The preset direction is the direction from the bottom edge of the front wall to the top edge of the front wall.

5. The wafer basket according to claim 1, characterized in that, There are two support parts, namely a first support part and a second support part. The first support part is located in the region between the first inclined side of the second region of the front wall, the bottom edge of the first side wall and the rear wall. The second support part is located in the region between the second inclined side of the second region of the front wall, the bottom edge of the second side wall and the rear wall. The first inclined side and the second inclined side of the second region are two opposite sides.

6. The wafer basket according to claim 5, characterized in that, The first support portion includes a plurality of second slots, and the second support portion includes a plurality of third slots, the second slots and the third slots being fitted to both sides of the vertically placed wafer.

7. The wafer basket according to claim 1, characterized in that, The edges of the first and second hollow areas are completely closed, while the edge of the third hollow area is not completely closed.

8. The wafer basket according to claim 7, characterized in that, The third hollow area has two parts, namely a first sub-area and a second sub-area. A second crossbeam is provided between the first sub-area and the second sub-area. The edge of the first sub-area has two sides and a bottom edge, forming the top opening of the rear wall. The edge of the second sub-area has two sides and a top edge, forming the bottom opening of the rear wall.

9. The wafer basket according to claim 8, characterized in that, The first sub-region is a trapezoidal region, and the second sub-region is a rectangular region.

10. The wafer basket according to any one of claims 1 to 8, characterized in that, Also includes: At least one first support foot, the first support foot being in contact with the front wall, the first side wall and the rear wall respectively; At least one second support foot, which contacts the front wall, the second side wall and the rear wall respectively, and the first support foot and the second support foot are used to support the chamber.

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