A bearing structure and semiconductor cleaning apparatus

Abstract

The application belongs to the technical field of semiconductor wet cleaning and provides a bearing structure and a semiconductor cleaning device, wherein the bearing structure comprises a bearing table base, a tilting driving assembly and a wafer constraint assembly; the tilting driving assembly is connected to the bottom of the bearing table base; the bearing structure takes 0-90° stepless tilting of the bearing table as a single main control dimension, different angle intervals correspond to corresponding wafer constraint states, and three levels of workstations of horizontal static placement, low inclined placement and high inclined placement are sequentially formed; the wafer and the bearing surface form a wedge-shaped gap under the low inclined placement workstation, and the wedge-shaped gap cooperates with a flow guide groove to form a directional flow channel, and the flow field shear effect is optimized by using the Venturi effect; the high inclined placement workstation can cover the side edge profile of the wafer and realize orderly discharge of waste liquid, multi-stage cleaning procedures are integrated in a single workstation, the cleaning flow field uniformity can be optimized, the fixed contact blind area can be reduced, the cross contamination and liquid accumulation residual risk can be reduced, and the cleaning consistency and procedure operation efficiency can be improved.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor wet cleaning technology, and particularly relates to a support structure and semiconductor cleaning equipment. Background Technology

[0002] In semiconductor wafer manufacturing processes, wet cleaning is a core step in removing particles, metallic impurities, and organic contaminants from the wafer surface. The cleaning effect directly impacts device yield and product reliability. Patent document CN120914083A, entitled "Method for Tilted Cleaning of Semiconductor Chips," discloses a tilted cleaning scheme. This scheme uses a fixture tilted to one side of the transport direction, with a nozzle moving along the chip arrangement direction to rinse the gaps between the chips. Alternating tilting on both sides increases the coverage area. While this scheme introduces tilting posture to assist cleaning, it only uses a fixed angle adjustment and does not deeply integrate angle control with the wafer constraint mode. Therefore, it still has many shortcomings in practical applications and cannot meet the high-precision cleaning requirements of advanced process wafers.

[0003] The specific problems with the existing technology are as follows: Angle adjustment and constraint mode are independent of each other, which can easily form a fixed contact blind zone: The angle adjustment and wafer clamping constraint of the existing tilt cleaning equipment are two independent control dimensions, requiring multiple sets of drive mechanisms to work together. The control logic is complex and the positioning accuracy is limited. The contact position between the wafer and the support structure is fixed. After long-term operation, the contact area cannot be effectively rinsed by the solution, which can easily form a cleaning blind zone. At the same time, fixed contact can easily cause extrusion damage to the functional surface of the wafer, and it is impossible to eliminate the risk of contact contamination and damage from the structural level. The gap flow field is not directionally constrained, the shear force is insufficient and cross-contamination is easy to occur: Under the current tilt state, the gap between the wafer and the support stage is not directionally flowed, the liquid flow is disordered and turbulence and dead zone are easily formed, the shear force distribution of the flow field is uneven, and the removal effect on submicron particles is limited. At the same time, the front and back cleaning are mostly carried out by synchronous spraying, and the waste liquid on the front can easily flow along the gap to the back, causing cross-contamination. It is impossible to achieve independent and undisturbed deep cleaning of the front and back, and the cleaning consistency is difficult to guarantee. Insufficient coverage of side contour cleaning and incomplete drainage can easily form dead corners for liquid accumulation: The spray range of the existing cleaning station is mostly concentrated on the front and back of the wafer, which cannot effectively cover the side contour and edge chamfer area of ​​the wafer, easily forming dead corners for edge cleaning. As a result, the impurities attached to the side cannot be fully washed off. At the same time, when the tilt angle is insufficient, liquid can easily remain in the wafer gap and the bottom of the cavity. The contaminants accumulated in the liquid can easily cause secondary pollution and affect the final cleaning cleanliness. The separate setup of pre-cleaning and main cleaning processes results in low throughput efficiency and a high risk of secondary contamination: In existing processes, pre-cleaning of large particles and deep main cleaning are usually completed at different workstations. Wafers need to be transferred between multiple cavities, which not only lengthens the process flow cycle and reduces production cycle efficiency, but also easily introduces environmental particulate pollution during the transfer process. Furthermore, the loading and positioning and pre-cleaning cannot be completed in the same orientation. Starting cleaning after positioning can easily cause uneven particle adhesion in the initial state.

[0004] Therefore, a support structure and semiconductor cleaning equipment are needed to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a support structure and a semiconductor cleaning device to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a support structure, comprising a support platform base, a tilting drive assembly, and a wafer constraint assembly; the tilting drive assembly is connected to the bottom of the support platform base and is used to drive the support platform base to tilt steplessly within an angle range of 0-90°; the wafer constraint assembly is disposed on the support surface of the support platform base; Adopting a stepless tilt bearing architecture, angle driving and wafer constraint are integrated on the same base. The gap shape adjustment and constraint state switching are realized simultaneously in a single tilt dimension. The overall structure is compact and the control dimension is simplified, which can adapt to the cleaning needs of multiple scenarios.

[0007] In a further technical solution, the tilt drive assembly includes a servo drive unit, an angle detection unit, and a support shaft; the support shaft is fixedly mounted on one side of the support platform base; the output end of the servo drive unit is connected to the support shaft for transmission; the angle detection unit is located at the end of the support shaft. By employing a servo drive in conjunction with an angle closed-loop detection structure, it can achieve precise stopping and smooth transition at any angle within the range of 0-90°. The angle control accuracy is high, and it can match the optimal process parameters of wafers of different sizes and different solutions, which helps to broaden the process adaptability range of the equipment.

[0008] A further technical solution is that the wafer constraint assembly includes multi-point limiting posts and a flexible support; the multi-point limiting posts are arranged at intervals along the circumference of the support platform base and protrude vertically from the support surface; the flexible support is disposed in the middle region of the support platform base and the protrusion height is less than the protrusion height of the multi-point limiting posts. The system adopts a combination structure of circumferential limiting posts and central flexible support. In the horizontal state, the surface support ensures positioning stability, while in the inclined state, the edge line contact reduces the contact area, which helps to reduce the probability of the formation of fixed contact blind spots.

[0009] A further technical solution is that a flow guide groove structure is provided on the bearing surface of the bearing platform base; the flow guide groove structure extends along the tilting direction of the bearing platform base, and the two ends of the groove penetrate the high edge and low edge of the bearing surface. Setting a guide channel extending along the tilting direction on the bearing surface can converge the flow path of the liquid medicine within the wedge-shaped gap, reduce turbulence, guide the waste liquid to flow out in a directional manner, and help improve the uniformity of the flow field and the orderliness of the discharge.

[0010] A further technical solution is that when the support platform base is in an inclined state, the wafer abuts against the multi-point limiting post on the lower side, and a wedge-shaped gap that gradually changes along the inclined direction is formed between the back of the wafer and the support surface of the support platform base. By utilizing the height difference between the limiting post and the supporting component, a gradually changing wedge-shaped gap is naturally formed in the tilted state. No additional lifting mechanism is required; the gap can be self-adapted by gravity. The structure is simple and reliable, and the gap shape can continuously change with the tilt angle.

[0011] A semiconductor cleaning device, applied to any of the aforementioned support structures, further includes a cleaning chamber, a spray assembly, and a drainage assembly; the support structure is rotatably disposed within the internal space of the cleaning chamber; the spray assembly is disposed on the inner wall of the cleaning chamber corresponding to the support area of ​​the support structure; and the drainage assembly is disposed at the bottom of the cleaning chamber. The load-bearing structure is integrated into the closed cleaning chamber, and together with the spray and drainage components, it forms a complete single-chamber cleaning system. The equipment has a small footprint, strong process compatibility, and can be embedded in existing production lines to replace traditional multi-station cleaning chambers.

[0012] A further technical solution is that the spray assembly includes an upper spray unit, a lower spray unit, and a side spray unit; the upper spray unit is disposed on the top inner wall of the cleaning chamber, directly facing the central area of ​​the support platform base; the lower spray unit is disposed below the support platform base; and the side spray unit is disposed on the side wall of the cleaning chamber, directly facing the side contour area of ​​the wafer. It adopts three independent spray units: upper, lower, and side. It can be selectively started and stopped according to the angle of the work station, realizing alternating cleaning of the front and back sides and supplementary cleaning of the side contours, which helps to expand the cleaning coverage and reduce the dead corners of edge cleaning.

[0013] A further technical solution is provided, wherein the drainage component includes a guide slope and a collection tank; the guide slope is disposed on the bottom inner wall of the cleaning chamber, and the inclination direction is consistent with the tilting direction of the support platform base; the collection tank is disposed at the lowest end of the guide slope, and an outlet is opened at the bottom of the tank. The structure adopts a guide slope combined with an end collection tank. The discharge direction is consistent with the tilting direction of the support platform. The waste liquid can flow smoothly into the collection tank along the slope, which plays a buffering and homogenizing role and helps to reduce the risk of discharge splash and liquid residue.

[0014] A further technical solution also includes a drying and purging assembly; the drying and purging assembly is disposed on the side wall of the cleaning chamber, with the air outlet facing the bearing area of ​​the bearing structure; An independent drying and purging component is added, which can simultaneously start gas purging during the high-angle liquid drainage stage to help remove residual droplets on the wafer surface, thus shortening the drying time and reducing water marks.

[0015] A further technical solution also includes a control unit; the control unit is installed outside the cleaning chamber and is electrically connected to the servo drive unit, angle detection unit, upper spray unit, lower spray unit, side spray unit, and drying and blowing assembly, and has built-in mapping logic between angle range and cleaning mode; With built-in angle-cleaning mode mapping logic, the corresponding spray parameters can be automatically switched after the tilt angle of the support platform is adjusted to the correct position, realizing the linkage control between angle adjustment and cleaning process, which helps to improve the synergy of system operation and reduce the complexity of manual operation.

[0016] The core technical points of this invention are divided into three progressive levels, which form an organically synergistic technical whole: The first layer is the basic structural layer: the stepless tilting bearing platform with its binding angle and constraint mode is the structural foundation of the entire device. It achieves multi-station switching through single-dimensional control, providing a stable working condition for subsequent flow field optimization and solving the fundamental problems of dispersed control dimensions and fixed contact blind zones in existing technologies.

[0017] The second layer is the flow field enhancement layer: the wedge gap and the guide groove form a directional Venturi flow channel, which is the core of improving cleaning quality and drainage stability. It not only enhances the cleaning shearing effect on the wafer surface, but also allows the waste liquid to be discharged in an orderly and stable manner, thereby improving the cleaning uniformity and drainage thoroughness from the perspective of fluid characteristics.

[0018] The third layer is the system integration layer: the three-level single-cavity integrated full-process cleaning is the key to achieving efficiency upgrades. It integrates pre-cleaning, deep main cleaning, side cleaning and drainage drying into the same station, eliminating process transfer links and improving operating efficiency and cleanliness from the system level.

[0019] The three technologies work together to support each other and achieve full-link optimization of "structural simplification, flow field optimization, and efficiency improvement". Compared with existing technologies that only improve the angle or only improve the spray, it has a more significant comprehensive performance advantage.

[0020] Compared with the prior art, the beneficial effects of the present invention are: This invention features a single-dimensional controllable binding constraint mode, reducing contact blind spots at the structural level: using the 0-90° stepless tilt of the support platform base as the sole control dimension, the tilt drive component precisely controls the angle range, and in conjunction with the wafer constraint component, achieves automatic switching of the constraint mode: the horizontal position is supported and positioned by the flexible support surface, and the tilt position is limited by the edge of the multi-point limiting column. The contact position changes dynamically with the tilt angle, eliminating the need for additional multi-axis adjustment mechanisms, simplifying the control logic and equipment architecture, and avoiding permanent blind spots formed by fixed contact points. This reduces the risk of contact damage to the wafer functional surfaces and improves the integrity of the cleaning coverage. This invention utilizes a wedge-shaped gap flow channel combined with the Venturi effect to enhance cleaning power and reduce cross-contamination. By using the height difference between multi-point limiting posts and flexible support components, a gradually changing wedge-shaped gap is formed between the wafer and the support surface at a low-sloping position. Combined with the guide groove structure on the support surface, a directional flow channel is formed. When the liquid flows from top to bottom along the gap, the flow cross-section gradually shrinks, generating a Venturi acceleration effect and increasing the shear force of the flow field. This enhances the removal effect of fine particles. At the same time, the upper spray unit and the lower spray unit can work independently and alternately. The waste liquid flows out unidirectionally along the inclined direction, which can reduce cross-contamination between the front and back sides, achieve a wider range of coverage cleaning, and make the flow field state more stable. This invention features a large-gap, high-angled design that covers the side contours and facilitates rapid liquid drainage, reducing dead zones for liquid accumulation. In this high-angled position, a large wedge-shaped gap is formed between the wafer and the supporting surface, allowing the sprayed cleaning solution to reach the wafer's side contours and chamfered areas. Combined with the side spray unit, this achieves full-surface coverage cleaning, improving the rinsing efficiency of impurities attached to the sides. Simultaneously, the larger angle of inclination gives the waste liquid a stronger gravitational velocity. Combined with the guide slope and collection tank at the bottom of the cleaning chamber, the waste liquid can be quickly discharged from the chamber along the inclined path, significantly reducing the amount of residual liquid on the wafer surface and in the gaps. This structurally reduces dead zones for liquid accumulation and mitigates the risk of secondary contamination. This invention integrates multiple cleaning processes in a single workstation, continuously improving process efficiency: the horizontal static positioning can simultaneously complete two functions: first, it achieves precise wafer loading and positioning through wafer constraint components, ensuring the consistency of gaps in subsequent tilting workstations; second, it initiates low-pressure cyclone pre-cleaning to remove large particle contaminants from the wafer surface in advance, preventing large particles from scratching the wafer surface during deep cleaning. By integrating loading and positioning with pre-treatment in the same workstation, pre-preparation can be completed without transferring to another process. The entire cleaning process can be completed in a single chamber, shortening process flow time and avoiding environmental particulate contamination during transfer, which helps improve cleaning yield and production line operating efficiency.

[0021] To more clearly illustrate the structural features and effects of the present invention, the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0022] Figure 1 This is a block diagram of the overall architecture of the present invention; Figure 2 This is a schematic diagram of the internal structure of the spray assembly of the present invention; Figure 3 This is a schematic diagram of the internal structure of the drainage component of the present invention; Figure 4 This is a schematic diagram of the structural connection of the control unit of the present invention.

[0023] In the diagram: 1. Support platform base; 2. Tilting drive assembly; 21. Servo drive unit; 22. Angle detection unit; 23. Support shaft; 3. Wafer constraint assembly; 31. Multi-point limiting post; 32. Flexible support component; 4. Guide channel structure; 5. Cleaning chamber; 6. Spray assembly; 61. Upper spray unit; 62. Lower spray unit; 63. Side spray unit; 7. Drainage assembly; 71. Guide slope; 72. Collection tank; 8. Drying and purging assembly; 9. Control unit. Detailed Implementation

[0024] The present invention will be further described below with reference to embodiments.

[0025] The following embodiments are used to illustrate the present invention, but should not be used to limit the scope of protection of the present invention. The conditions in the embodiments can be further adjusted according to specific conditions, and simple improvements to the method of the present invention under the premise of the concept of the present invention are all within the scope of protection claimed by the present invention.

[0026] Example 1 like Figure 1-4 As shown, this embodiment of the invention provides a semiconductor cleaning device, including a support structure, a cleaning chamber 5, a spray assembly 6, a drain assembly 7, a drying and purging assembly 8, and a control unit 9.

[0027] The support structure is located inside the cleaning chamber 5 and includes a support base 1, a tilt drive assembly 2, and a wafer constraint assembly 3. The support base 1 is a circular plate structure with a support shaft 23 fixedly inserted on one side. The two ends of the support shaft 23 are rotatably connected to the inner wall of the cleaning chamber 5, forming the tilt fulcrum of the entire support structure. The tilt drive assembly 2 includes a servo drive unit 21 and an angle detection unit 22. The servo drive unit 21 is installed on the outer wall of the cleaning chamber 5, and its output end is connected to one end of the support shaft 23 for transmission. It is used to output torque to drive the support base 1 to rotate around the support shaft 23. The angle detection unit 22 is installed on the other end of the support shaft 23 for real-time acquisition of the rotation angle signal of the shaft and feedback of the signal to the control unit 9 to form an angle closed-loop control, realizing stepless precise tilting within the range of 0-90°.

[0028] The wafer constraint assembly 3 is disposed on the upper surface of the support base 1, including multiple multi-point limiting posts 31 and multiple flexible support members 32; the multi-point limiting posts 31 are evenly spaced along the circumference of the support base 1, with no less than three posts, all of which protrude vertically from the support surface; the flexible support members 32 are disposed in the central area of ​​the support base 1, arranged in a ring, and their protrusion height is less than the protrusion height of the multi-point limiting posts 31; when the support base 1 is in a horizontal state, the wafer is placed on the flexible support member 32, and the back side only contacts the flexible support member 32, while the functional area does not directly contact the support surface; when the support base 1 is tilted, the wafer slides to the lower side under the action of gravity, and the edge abuts against the lower multi-point limiting post 31, at which time a wedge-shaped gap that gradually changes along the tilt direction is formed between the back side of the wafer and the support surface of the support base 1.

[0029] Multiple guide channel structures 4 are also provided on the bearing surface of the bearing platform base 1. The guide channel structures 4 extend parallel to the tilting direction of the bearing platform, running from the high end to the low end, and are used to guide the liquid medicine in the wedge gap to flow along the directional path and converge the flow field path.

[0030] The spray assembly 6 includes an upper spray unit 61, a lower spray unit 62, and a side spray unit 63. The upper spray unit 61 is installed on the top inner wall of the cleaning chamber 5, facing the center area of ​​the support platform base 1, and is used to spray cleaning solution onto the front side of the wafer. The lower spray unit 62 is installed below the support platform base 1, and the solution can pass through the hollow area of ​​the support platform to be sprayed onto the back side of the wafer. The side spray unit 63 is installed on the side wall of the cleaning chamber 5, facing the side contour of the wafer. All three spray units are independently controlled by the control unit 9, and can be started, stopped, and have their flow and pressure parameters adjusted individually.

[0031] The drainage assembly 7 is located at the bottom of the cleaning chamber 5 and includes a guide slope 71 and a collection tank 72. The guide slope 71 is the inclined inner wall of the bottom of the cleaning chamber 5, and the inclination direction is consistent with the tilting direction of the support base 1, with the lower end facing the opposite side of the support shaft 23; the collection tank 72 is located at the lowest end of the guide slope 71, and has an outlet at the bottom for discharging the collected waste liquid.

[0032] The drying and purging assembly 8 is installed on the side wall of the cleaning chamber 5, with its outlet facing the bearing area of ​​the support platform base 1. It can spray high-purity nitrogen to assist in wafer drying. The control unit 9 is installed outside the cleaning chamber 5 and is electrically connected to the servo drive unit 21, angle detection unit 22, upper spray unit 61, lower spray unit 62, side spray unit 63, and drying and purging assembly 8. The control unit 9 has a built-in mapping logic between angle ranges and cleaning modes: the 0° horizontal range corresponds to the pre-cleaning mode, the low angle range corresponds to the deep main cleaning mode, and the high angle range corresponds to the full-contour drainage and drying mode.

[0033] In this embodiment, the formula for calculating the waste liquid discharge flow rate at the inclined station corresponding to the drainage structure is as follows:

[0034] in: : Volumetric discharge flow rate of waste liquid from the wafer surface, in L / min; : The overall flow resistance coefficient of waste liquid flow, dimensionless; Through preliminary process experiments and calibration, parameters related to the viscosity of the solution, the surface roughness of the wafer, and the structural parameters of the guide channel are pre-stored in the parameter library of the control unit 9. : The tilt angle of the bearing platform base 1, in degrees; The angle detection unit 22 collects data in real time and sends it back to the control unit 9; : Effective cross-sectional area for current flow on the wafer surface, in m²; It is calculated from the nominal dimensions of the wafer and the tilt angle θ through geometric projection relationships.

[0035] Constraints: The value range is 0° < θ ≤ 90°; The waste liquid flows continuously by gravity on the wafer surface without interruption or splashing.

[0036] Control logic: The control unit 9 calculates the required tilt angle θ according to the set drainage time requirement using the formula, and controls the servo drive unit 21 to adjust to the corresponding angle so that the drainage flow rate meets the process cycle requirements, while avoiding excessive flow rate and waste liquid splashing.

[0037] The formula for calculating the waste liquid discharge flow rate at tilted workstations can quantify and predict the discharge rate at different tilt angles, enabling controllable discharge of waste liquid, ensuring smooth and orderly discharge, reducing residual liquid accumulation, and providing a theoretical basis for adjusting process parameters for wafers of different sizes.

[0038] In this embodiment, the equipment's workflow is as follows: After the wafer is loaded, the support platform base 1 is in a horizontal, static position. After precise positioning, the upper spray unit 61 is activated to perform low-pressure swirling pre-cleaning to remove large particulate contaminants from the surface. Subsequently, the support platform base 1 is continuously tilted to a low-inclination zone, forming a wedge-shaped gap between the wafer and the support surface. The upper and lower spray units are alternately activated for deep main cleaning. Then, the support platform base 1 continues to tilt to a high-inclination zone, and the side spray unit is activated to clean the side contours, with waste liquid being quickly discharged. Finally, the drying and blowing assembly 8 is activated to complete the drying process, and the support platform is reset before unloading.

[0039] Example 2 The difference between this embodiment and embodiment 1 is that: the wafer confinement assembly 3 is equipped with a vacuum adsorption structure, and an annular vacuum adsorption tank is set in the central area of ​​the support platform base 1. The vacuum adsorption tank is connected to an external vacuum generator through a gas pipeline, and the vacuum generator is controlled by the control unit 9.

[0040] In this embodiment, during pre-cleaning in a horizontal, stationary position, the vacuum adsorption tank activates negative pressure, firmly adsorbing the back side of the wafer onto the support platform base 1. This further improves positioning accuracy and allows for adaptation to higher-speed vortex pre-cleaning conditions, optimizing the uniformity and efficiency of pre-cleaning. Before the support platform enters the inclined position, the control unit 9 releases the vacuum adsorption, and the wafer slides towards the lower multi-point limiting posts 31 under gravity, forming a wedge-shaped gap. This structure improves the positioning stability of the horizontal position while retaining the low-damage characteristics of edge contact in the inclined position, balancing positioning accuracy and cleaning coverage. It is suitable for process scenarios with high requirements for pre-cleaning uniformity. The suction parameters generated by the vacuum adsorption can be adjusted by the control unit 9 according to the wafer thickness to adapt to wafer products of different specifications, avoiding excessive suction that could cause deformation of the back side of the wafer.

[0041] Example 3 The difference between this embodiment and embodiment 1 is that the flow guide structure 4 adopts a spiral flow guide. Multiple spiral grooves extend in a spiral diverging shape along the tilting direction from the center of the support platform base 1 as the origin, and the cross-section of the groove adopts a rounded transition design.

[0042] In this embodiment, after the liquid enters the wedge-shaped gap, it generates a circumferential swirling component as it flows along the spiral guide groove. Combined with the longitudinal Venturi acceleration effect, this forms a spiral accelerated flow field, resulting in a more uniform shearing effect on the back side of the wafer. This further optimizes the uniformity of particle and impurity removal, making it particularly suitable for ultra-thin wafer cleaning processes with high uniformity requirements. The spiral flow channel also extends the effective action path of the liquid within the gap, improving liquid utilization and reducing chemical consumption. The pitch and depth parameters of the spiral groove can be matched and designed according to different liquid viscosities to maintain a relatively stable flow field and reduce turbulence and cavitation.

[0043] In this embodiment, the formula for calculating the Venturi velocity in the wedge-shaped gap corresponding to flow field optimization is as follows: ;

[0044] in: Initial flow velocity of the drug solution at the inlet of the wedge-shaped gap, in m / s; The flow rate is calculated by the control unit 9 based on the set flow rate of the upper spray unit 61 and the cross-sectional area of ​​the nozzle outlet. The flow rate parameter can be collected in real time by the spray valve group. The velocity of the liquid after acceleration at the narrow end of the wedge-shaped gap is expressed in m / s. The height of the wedge-shaped gap at the high inlet is in mm. The height of the wedge-shaped gap at its narrowest lower end, in mm; , The tilt angle θ of the bearing platform base 1, the height of the multi-point limiting column 31, and the height of the flexible support 32 are calculated through geometric relationships. The tilt angle θ is fed back in real time by the angle detection unit 22.

[0045] Constraints: The tilt angle θ is within the low-slope position range to ensure that the wafer is stably abutted against the multi-point limiting post 31; To avoid direct contact between the back of the wafer and the support platform 1; The liquid is in a continuous laminar flow state, and the Reynolds number is in the laminar flow range.

[0046] Control logic: Control unit 9 calculates the corresponding target flow rate based on the target shear force set in the process. Then, by adjusting the tilt angle θ, the change The value is set so that the actual flow velocity matches the target value, thereby achieving precise control of the flow field shear force.

[0047] The flow velocity amplification effect of the wedge gap can be quantified by the Venturi velocity calculation formula, providing a theoretical basis for process parameter adjustment. This allows for relatively stable flow field shear force to be obtained under different wafer sizes and different chemical solutions, thus improving the consistency of cleaning effect.

[0048] Example 4 The difference between this embodiment and embodiment 1 is that the tilt drive assembly 2 adopts a dual servo drive synchronous structure. A set of servo drive units 21 and a support shaft 23 are set on each side of the support platform base 1. The two sets of drive units are synchronously controlled by the control unit 9 to output torque.

[0049] In this embodiment, dual-point synchronous support and drive improve the tilting stability of the support platform base 1, avoiding platform deflection and vibration when supporting large-size wafers, and can adapt to the cleaning needs of larger-size wafers. The dual-drive structure also has redundancy backup capability; if one drive fails, the other can maintain basic operation, improving the reliability of equipment operation. Angle detection units 22 are respectively set at the ends of the two support shafts 23, and the control unit 9 further improves the angle detection accuracy and reduces detection error through dual-channel signal verification. This structure is suitable for the high reliability operation requirements of large-size wafer mass production lines, and can effectively reduce the risk of wafer displacement caused by vibration during tilting, ensuring the consistency of gap shape.

[0050] Example 5 The difference between this embodiment and embodiment 1 is that the spray assembly 6 also integrates a megaphonic vibration unit, which is coupled to the nozzles of the upper spray unit 61 and the lower spray unit 62 respectively, and its start / stop and power parameters are independently controlled by the control unit 9.

[0051] In this embodiment, during the low-angle depth main cleaning stage, the megasonic vibration unit starts synchronously with the spray. Megasonic energy is transferred to the wafer surface through the cleaning solution, generating a cavitation effect. Combined with the shear flow field of the wedge-shaped gap, this more efficiently removes nanoscale fine particles and tightly adhered impurities. This structure combines megasonic cleaning with wedge-shaped flow channel enhancement, improving cleaning capabilities and making it suitable for the fine cleaning needs of high-end process wafers. The megasonic power can be adjusted according to the wafer device structure, mitigating the device structure damage problems easily caused by traditional megasonic cleaning, thus optimizing cleaning effects while ensuring product yield.

[0052] In this embodiment, the formula for calculating the wafer surface shear stress corresponding to the cleaning effect is as follows:

[0053] in: Fluid shear stress at the wafer wall, in Pa; The dynamic viscosity of the cleaning solution, expressed in Pa·s; Determined by the type of liquid medicine and the working temperature, the process parameters are pre-stored in the process parameter library of control unit 9 and can be corrected in real time through temperature detection data; The velocity gradient of the liquid along the normal direction within the gap, expressed in seconds. -1 ; The velocity distribution and gap height are derived from the Venturi velocity formula and then calculated in real time by combining the tilt angle θ.

[0054] Constraints: The shear stress does not exceed the tolerance threshold of the wafer surface device structure; The liquid is in a continuous laminar flow state, without impact damage caused by cavitation collapse.

[0055] Control logic: The control unit 9 sets the target shear stress range based on the tolerance threshold corresponding to the wafer process node. By adjusting the spray flow rate and tilt angle, the actual shear stress is kept within the target range, balancing cleaning effect and device safety.

[0056] The mechanical shear stress calculation formula on the wafer surface can be used to quantitatively evaluate the intensity of mechanical shearing during the cleaning process, and to match the optimal cleaning parameters for wafers at different process nodes, thereby reducing the risk of device damage while ensuring cleaning efficiency.

[0057] Example 6 The difference between this embodiment and embodiment 1 is that the drainage assembly 7 is equipped with a negative pressure extraction unit, which is connected to the outlet of the collection tank 72 and its operating power is controlled by the control unit 9.

[0058] In this embodiment, during the high-inclination drainage stage, the negative pressure extraction unit is simultaneously activated, creating a micro-negative pressure environment within the collection tank 72. This accelerates the flow of waste liquid on the guide slope 71 and simultaneously extracts residual liquid from the wedge-shaped gap, further shortening the drainage time and improving the thoroughness of drainage. The negative pressure extraction also creates a micro-negative pressure within the cleaning chamber 5, reducing the overflow of chemical mist and improving the equipment's adaptability to clean environments. This makes it suitable for cleanroom scenarios with stringent waste gas control requirements. The power of the negative pressure extraction can be dynamically adjusted according to the drainage stage. Higher power is used for rapid drainage in the initial stage, while lower power is used to maintain negative pressure in the final stage, balancing drainage efficiency and energy consumption control.

[0059] Example 7 The difference between this embodiment and embodiment 1 is that a heating module is embedded inside the support platform base 1. The heating module adopts a uniformly arranged heating wire structure and is electrically connected to the control unit 9. A temperature detection element is set below the support surface.

[0060] In this embodiment, the heating module can precisely control the temperature of the support platform base 1 during the cleaning process. Through heat conduction and radiation, it raises the temperature of the chemical solution within the wedge-shaped gap, enhancing the reactivity of the chemical solution and optimizing the removal efficiency of organic pollutants and metallic impurities. Temperature parameters can be adjusted according to the characteristics of different chemical solutions, resulting in a wider range of process adaptability. The heating module employs a uniform wiring design, forming a closed-loop temperature control system with temperature detection elements to ensure temperature consistency on the support surface and mitigate the risk of wafer warpage caused by localized temperature differences. Temperature control data is synchronously connected to the control unit 9, which can be linked with the spray parameters to adjust the spray flow rate and tilt angle according to the chemical solution temperature, ensuring stable cleaning results at different temperatures.

[0061] Example 8 The difference between this embodiment and embodiment 1 is that the wafer constraint assembly 3 adopts an adjustable structure, the multi-point limiting post 31 is installed in the radial groove of the support platform base 1, and can be moved radially and locked by the adjustment mechanism. The flexible support 32 adopts a modular splicing structure, and the arrangement range can be adjusted according to the wafer size.

[0062] In this embodiment, by adjusting the radial position of the multi-point limiting posts 31 and the arrangement range of the flexible support 32, it can adapt to various wafer products of different sizes without replacing the entire support stage, thus improving the process compatibility of the equipment. The adjustment mechanism is equipped with a position scale, which can achieve precise positioning and ensure that the center of wafers of different sizes coincides with the center of the support stage, avoiding uneven wedge gaps caused by eccentricity. This structure is suitable for wafer cleaning production lines with multiple varieties and small batches, and can quickly switch product specifications, reduce changeover time, and improve equipment utilization. The locking structure has a self-locking function, which can ensure that the position of the limiting posts does not shift during tilting, ensuring the stability of wafer positioning.

[0063] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A load-bearing structure, characterized in that, It includes a support platform base (1), a tilt drive assembly (2), and a wafer constraint assembly (3); the tilt drive assembly (2) is connected to the bottom of the support platform base (1); the wafer constraint assembly (3) is disposed on the support surface of the support platform base (1).

2. The load-bearing structure according to claim 1, characterized in that, The tilt drive assembly (2) includes a servo drive unit (21), an angle detection unit (22), and a support shaft (23); the support shaft (23) is fixedly installed on one side of the support platform base (1); the output end of the servo drive unit (21) is connected to the support shaft (23) in a transmission manner; the angle detection unit (22) is located at the end of the support shaft (23).

3. The load-bearing structure according to claim 1, characterized in that, The wafer constraint assembly (3) includes a multi-point limiting post (31) and a flexible support (32); the multi-point limiting post (31) is arranged circumferentially along the support platform base (1) and protrudes vertically from the support surface; the flexible support (32) is located in the middle region of the support platform base (1) and its protrusion height is less than that of the multi-point limiting post (31).

4. A load-bearing structure according to claim 1, characterized in that, A flow guide structure (4) is provided on the bearing surface of the bearing platform base (1); the flow guide structure (4) extends along the tilting direction of the bearing platform base (1), and the two ends of the channel penetrate the high edge and low edge of the bearing surface.

5. A load-bearing structure according to claim 3, characterized in that, When the support base (1) is tilted, the wafer abuts against the multi-point limiting post (31) on the lower side, and a wedge-shaped gap that gradually changes along the tilt direction is formed between the back of the wafer and the support surface of the support base (1).

6. A semiconductor cleaning apparatus, applied to the support structure according to any one of claims 1-5, characterized in that, It also includes a cleaning chamber (5), a spray assembly (6) and a drain assembly (7); the supporting structure is rotatably disposed in the internal space of the cleaning chamber (5); the spray assembly (6) is disposed on the inner wall of the cleaning chamber (5) corresponding to the supporting area of ​​the supporting structure; the drain assembly (7) is disposed at the bottom of the cleaning chamber (5).

7. A semiconductor cleaning apparatus according to claim 6, characterized in that, The spray assembly (6) includes an upper spray unit (61), a lower spray unit (62), and a side spray unit (63); the upper spray unit (61) is located on the top inner wall of the cleaning chamber (5), facing the central area of ​​the support platform base (1); the lower spray unit (62) is located below the support platform base (1); and the side spray unit (63) is located on the side wall of the cleaning chamber (5), facing the side contour area of ​​the wafer.

8. A semiconductor cleaning apparatus according to claim 6, characterized in that, The drainage assembly (7) includes a guide slope (71) and a collection tank (72); the guide slope (71) is located on the bottom inner wall of the cleaning chamber (5), and its tilt direction is consistent with the tilt direction of the support base (1); the collection tank (72) is located at the lowest end of the guide slope (71), and an outlet is opened at the bottom of the tank.

9. A semiconductor cleaning device according to claim 6, characterized in that, It also includes a drying and purging assembly (8); the drying and purging assembly (8) is disposed on the side wall of the cleaning chamber (5), with the air outlet facing the bearing area of ​​the bearing structure.

10. A semiconductor cleaning apparatus according to claim 6, characterized in that, It also includes a control unit (9); the control unit (9) is installed outside the cleaning chamber (5) and is electrically connected to the servo drive unit (21), angle detection unit (22), upper spray unit (61), lower spray unit (62), side spray unit (63), and drying and blowing assembly (8), respectively, and has built-in mapping logic between angle range and cleaning mode.

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