A square piece of adhesive coated carrier disc
By designing a square-shaped coating tray that combines a central island-style sunken platform with an annular drainage channel, the problems of adhesive backflow and airflow disturbance during the coating process of square wafers were solved, thereby improving film thickness uniformity and product quality and reducing equipment maintenance difficulty.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XINMI (XIAMEN) SEMICON EQUIP CO LTD
- Filing Date
- 2026-03-19
- Publication Date
- 2026-07-07
AI Technical Summary
Existing spin coating equipment faces serious problems when coating square wafers, such as uneven resist thickness caused by edge airflow disturbance and back-side contamination caused by the convergence of photoresist centrifugal jets, which affect product quality and production efficiency.
A square adhesive coating tray was designed, which combines a central island-style sunken platform with an annular drainage channel. It is equipped with negative pressure holes, air blowing holes and a vacuum tank. The drainage channel and drainage port are designed to block the backflow path of the adhesive, and the air blowing holes are used to form a dynamic air curtain to intercept the backflow of adhesive, thus creating a stable aerodynamic microenvironment.
It effectively solves the problem of adhesive backflow and contamination during the coating process of square wafers, improves film thickness uniformity and product yield, and reduces equipment maintenance frequency and cost.
Smart Images
Figure CN122343151A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of quartz wafer manufacturing, and mainly to a square-shaped coated carrier disk. Background Technology
[0002] In the manufacturing processes of semiconductor devices, microelectromechanical systems (MEMS), and advanced optoelectronic components, photolithography is the core process for patterning, and spin coating is currently the most common and primary method for coating photoresist. Traditional photolithography spin coating equipment is mainly designed for standard circular silicon wafers. However, with the rapid development of advanced packaging technologies (such as glass substrate packaging and panel-level fan-out packaging) and specific optical devices, the shape of the substrate to be processed is no longer limited to the traditional circle, and the industry's demand for high-precision photoresist coating on square substrates is becoming increasingly urgent.
[0003] Traditional round wafers possess perfect centrosymmetry when rotating at high speeds, with relatively stable airflow around their edges. However, when existing spin-coating equipment or conventional carriers are used for coating square wafers, they face extremely severe aerodynamic and hydrodynamic challenges, resulting in the following inherent defects in actual production using existing square carriers: severe edge airflow disturbances leading to uneven adhesive thickness; and back-side contamination caused by centrifugal jets and capillary action.
[0004] First, square wafers have four vertices and four straight edges. During high-speed rotary coating, the four protruding vertices violently cut through the surrounding air like fan blades, generating strong airflow turbulence and localized eddies above the wafer edges. This uneven airflow accelerates the evaporation of solvent in the photoresist at the wafer edges, resulting in a "thick at the edges, thin in the center" phenomenon in the final film. In particular, the four corners are prone to photoresist accumulation, severely affecting the accuracy of subsequent exposures. Second, under the action of centrifugal force, the photoresist gathers and is ejected from the four vertices along the diagonal of the square wafer. Since existing carriers are usually flat-bottomed support structures or only have simple placement slots, the large amount of photoresist gathered at the edges and corners is easily rolled up along the wafer sides during ejection and, driven by capillary action, drawn back into the gap between the wafer back and the carrier platform. This not only causes severe contamination on the back of the square wafer, leading to product scrap, but also causes the adhesive to dry and accumulate in the dead corners of the carrier, forcing the production line to frequently stop to clean the carrier, greatly reducing production efficiency.
[0005] In summary, developing a square substrate coating carrier that can effectively eliminate the aerodynamic disturbances caused by the edge-cutting airflow during high-speed rotation of square wafers, smoothly guide the corner centrifugal jet, and completely block the adhesive backflow path to prevent backside contamination is of great engineering application significance and industrial value for overcoming the process bottleneck of photolithography coating of square substrates, improving film thickness uniformity and product yield, and significantly reducing equipment maintenance costs. Summary of the Invention
[0006] In view of the technical problems in the prior art, such as uneven coating thickness caused by edge cutting airflow during high-speed spin coating of square wafers, and the easy capillary backflow of the ejected adhesive causing contamination on the back of the wafer, this application proposes a square sheet adhesive coating carrier.
[0007] According to one aspect of the present invention, a square-shaped adhesive-coated carrier disk is provided, comprising a carrier disk body, wherein an annular drainage groove is formed on the carrier disk body, the drainage groove dividing the carrier disk body into an inner central portion and an outer peripheral portion, the central portion forming a wafer stage with a square outer contour; the wafer stage is provided with a negative pressure hole, a blow-out hole and a vacuum groove; the peripheral portion has a reference upper surface, the wafer stage surface is lower than the reference upper surface of the peripheral portion, and the bottom surface of the drainage groove is lower than the wafer stage surface; the drainage groove extends diagonally along the wafer stage towards... The outer side of the peripheral portion extends to form a drainage port that penetrates the outer edge of the peripheral portion; the center line of the extension of the drainage port is aligned with the apex corner of the square wafer placed on the wafer stage; the upper surface of the square wafer placed on the wafer stage is lower than the reference upper surface of the peripheral portion; the edge of the square wafer protrudes from the side of the wafer stage and is suspended above the drainage groove, and there is a horizontal distance between the edge of the square wafer and the outer wall of the drainage groove; the air blowing hole extends downward from the side wall of the wafer stage to the bottom of the carrier body.
[0008] This invention cleverly cuts off the physical path of photoresist backflow through a design that combines a central island-style sunken platform with an annular deep groove. Simultaneously, the drainage port is precisely aligned with the four corners of the square wafer where centrifugal force is greatest, conforming to the hydrodynamic jet trajectory of the photoresist during high-speed rotation. This fundamentally solves the inherent problems of airflow disturbance at the square edge and capillary contamination on the back side. Furthermore, this application innovatively adds inclined, through-hole air vents to the sidewall of the wafer stage. During the coating process, continuous airflow through these vents into the suspended area at the bottom edge of the square wafer creates a dynamic positive pressure air curtain blowing outwards beneath the wafer. This active air curtain forcibly blows photoresist attempting to flow back through capillary action or centrifugal gravity into the drainage groove, achieving a defensive upgrade from "passive suspension isolation" to "active airflow interception," further eliminating the possibility of contamination on the back of the wafer.
[0009] Preferably, multiple additional drainage ports are also provided. These additional drainage ports are positioned corresponding to the side of the wafer stage and extend from the drainage groove outwards through the edge of the carrier body. The multiple additional drainage ports are symmetrically distributed on the carrier body. By adding symmetrically distributed additional drainage ports at the corresponding positions on the straight edge of the wafer stage, not only is the aerodynamic stability and dynamic balance of the carrier body during high-speed rotation further improved, but also excess adhesive overflowing from the straight edge of the wafer along the non-diagonal lines can be effectively guided and discharged, preventing adhesive accumulation in localized areas.
[0010] More preferably, the bottom surfaces of the drainage port and the additional drainage port are flush with the bottom surface of the drainage groove. This structure ensures that the photoresist ejected under centrifugal force is smoothly and unobstructedly discharged from the outside of the carrier, preventing high-viscosity adhesive from stagnating or drying in dead corners, thus reducing the frequency of equipment maintenance and cleaning.
[0011] More preferably, the width of both the drainage port and the additional drainage port is 8-12 mm. This size ensures that the adhesive collected at the edge has sufficient space for instantaneous discharge, while preventing the introduction of excessive external turbulent airflow due to overly large openings, thus avoiding interference with the coating microenvironment on the wafer surface.
[0012] Preferably, the inclination angle of the air blowing hole is 30°-60°, and the hole diameter is 0.3-0.8mm. This specific inclination angle design allows the blown airflow to be precisely guided obliquely downwards towards the guide groove, forming a powerful air curtain while preventing the airflow from being too vertically upwards, which could cause high-frequency vibrations in the wafer or interfere with the aerodynamic microenvironment of the coating above. Simultaneously, the 0.3-0.8mm micro-hole diameter ensures the initial dynamic pressure of the airflow injection, achieving optimal blowing effect. Preferably, there are at least two vacuum slots, each of which is a square loop shape adapted to the outer contour of the wafer stage and arranged concentrically on the wafer stage. This design enables the negative pressure adsorption force to uniformly cover the entire back side of the square wafer, effectively preventing edge warping or minor deformation of the square substrate due to uneven local stress under high-speed centrifugal force.
[0013] More preferably, the negative pressure hole is located at the center of the wafer stage, and the wafer stage is also provided with a connecting groove radiating outward from the negative pressure hole. Multiple vacuum grooves arranged in a concentric nested pattern are interconnected through the connecting groove. This structure ensures that a uniform vacuum level can be established simultaneously and rapidly in each of the nested vacuum grooves, greatly improving the response speed and overall adsorption stability during wafer loading.
[0014] More preferably, the distance between the outermost edge of the vacuum trench and the edge of the square wafer is ≤5mm. This provides a strong mechanical anchoring force for the suspended edge region of the square wafer, which is most prone to high-frequency vibration and airflow overturning effects, ensuring that the wafer edge maintains absolute flatness even at extremely high speeds.
[0015] Preferably, the height difference between the upper surface of the square wafer and the reference upper surface of the peripheral portion is ≥0.2mm. When the device rotates at high speed, this baffle structure can effectively block the external high-speed airflow cutting in the horizontal direction, creating a relatively static and uniform aerodynamic microenvironment above the wafer surface, thereby eliminating the abnormal coating edge thickness caused by the "wind shear effect".
[0016] Preferably, the edge of the square wafer protrudes 1-3 mm from the side of the wafer stage, and the distance between the edge of the square wafer and the outer wall of the drainage groove is ≥1 mm. This design effectively prevents the ejected adhesive from reversing and contaminating the back of the wafer.
[0017] Compared with the prior art, this application has the following beneficial effects: This application utilizes an innovative physical structure that combines a central island-style sunken platform with an annular deep groove. This structure causes the edges of the square wafer placed on the wafer stage to protrude outwards and be suspended above the deepest drainage groove, while maintaining a horizontal distance from the outer wall of the drainage groove. This cleverly breaks the capillary action conditions required for liquid reflux and completely blocks the reverse roll-up of the photoresist thrown out by centrifugal force from the physical path. This fundamentally solves the inherent problem of high-viscosity adhesive backflow contaminating the back of the square wafer and significantly improves product yield.
[0018] This application utilizes downward-sloping, penetrating air vents on the sidewall of the wafer stage to continuously supply air to the suspended area at the bottom of the wafer during adhesive coating, thereby creating an outward-facing dynamic positive pressure air curtain below the wafer edge. This active air curtain effectively intercepts and reverses the inward flow of high-viscosity adhesive, preventing liquid backflow. This design complements the existing physical suspension isolation structure, forming a dual anti-backflow mechanism that combines dynamic and static elements, ensuring that the back of the wafer is protected from any cross-contamination even in extremely harsh adhesive coating environments.
[0019] This application sets the wafer stage surface below the reference upper surface of the periphery, so that the upper surface of the square wafer is lower than the periphery. This successfully creates a relatively static and uniform aerodynamic microenvironment above the wafer surface, thereby eliminating the "wind shearing effect" and local eddies caused by the wafer apex cutting the air, and ensuring the consistency of film thickness in the edge area.
[0020] This application provides a sufficient and unobstructed drainage channel for excess photoresist that is thrown into the drainage tank during high-speed spin coating by setting a drainage port through the edge of the carrier disk. This ensures that the high-viscosity adhesive can be discharged from the outside of the carrier disk quickly and without obstruction, avoiding the adhesive from stagnating, drying and accumulating in the tank or dead corners, thereby greatly reducing the difficulty of cleaning the equipment and the frequency of downtime maintenance.
[0021] This application provides at least two square loop-shaped vacuum grooves on the wafer stage that are adapted to the outer contour of the wafer and are arranged in a concentric nested manner, so that the negative pressure adsorption force can uniformly cover the back side of the entire square wafer, effectively avoiding the slight deformation or warping of the square substrate due to uneven local force under the action of centrifugal force at extremely high speed. Attached Figure Description
[0022] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and, together with the description, serve to explain the principles of this application. Other embodiments and many anticipated advantages of these embodiments will be readily recognized as they become better understood through reference to the following detailed description. Elements in the drawings are not necessarily to scale. The same reference numerals refer to corresponding similar parts.
[0023] Figure 1 A schematic diagram of the overall structure of a square adhesive-coated carrier disk according to a specific embodiment of this application is shown; Figure 2 A top view of a square adhesive-coated carrier plate according to a specific embodiment of this application is shown; Figure 3 This diagram illustrates the effect of placing a square wafer on a square adhesive-coated carrier according to a specific embodiment of this application; Figure 4 A cross-sectional view of the AA side of a square adhesive-coated carrier disk according to a specific embodiment of this application is shown; The attached figures are labeled as follows: 1-Carrier body, 101-Outer peripheral reference upper surface, 2-Draining groove, 201-Draining port, 202-Additional drainage port, 203-Draining groove bottom surface, 3-Wafer stage, 301-Wafer stage surface, 4-Negative pressure hole, 5-Vacuum tank, 6-Square wafer, 7-Connecting groove, 8-Air blowing hole, 9-Screw fastening hole. Detailed Implementation
[0024] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.
[0025] Where there is no conflict, 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.
[0026] This application provides a square-shaped adhesive-coated carrier disk, as referenced. Figures 1-3 The system includes a carrier disk body 1, on which an annular drainage groove 2 is formed, dividing the carrier disk body 1 into an inner central part and an outer peripheral part. The central part forms a wafer stage 3 with a square outer contour. The wafer stage 3 is provided with a negative pressure hole 4 and a vacuum tank 5. This design, through ingenious physical spatial separation, lays the foundation for the subsequent construction of a gas flow-proof microenvironment and a backflow-proof structure.
[0027] Specifically, the drainage grooves 2 extend outward from the outer periphery along the diagonal direction of the wafer stage 3, forming drainage ports 201 that penetrate the outer edge of the periphery. Furthermore, the center line of the extension of the drainage ports 201 is aligned with the apex corners of the square wafer 6 placed on the wafer stage 3. This design perfectly conforms to the hydrodynamic trajectory of the photoresist, which inevitably converges and is ejected from the four apex corners where the centrifugal force is greatest when the square wafer rotates at high speed, thus ensuring that the photoresist at the corners can be accurately collected and smoothly discharged.
[0028] Continue to refer to Figure 1 and Figure 2 In a specific embodiment, the carrier body 1 is also provided with a plurality of additional drainage ports 202, which are provided on the side of the wafer stage 3 and extend from the drainage groove 2 to the outside of the carrier body 1 (i.e. the peripheral part) and penetrate through the edge of the carrier body 1; the plurality of additional drainage ports 202 are symmetrically distributed on the carrier body 1.
[0029] Specifically, the bottom surfaces of the drainage port 201 and the auxiliary drainage port 202 are flush with the bottom surface of the drainage channel 2; and the width of both the drainage port 201 and the auxiliary drainage port 202 is 8-12mm. The above-mentioned stepless and appropriately sized drainage channel design ensures that the high-viscosity adhesive can be discharged from the outside of the carrier without obstruction, avoiding drying and accumulation in dead corners.
[0030] Specifically, refer to Figure 4 The mesa 301 of the wafer stage 3 is lower than the reference upper surface 101 of the periphery, and the bottom surface 203 of the channel 2 is lower than the mesa 301 of the wafer stage. When placed on the wafer stage 3, the upper surface of the square wafer 6 is lower than the reference upper surface 101 of the periphery.
[0031] In a specific embodiment, the height difference between the upper surface of the square wafer 6 and the reference upper surface 101 of the outer periphery of the carrier disk body 1 is ≥0.2mm. (Reference) Figure 3The edge of the square wafer 6 protrudes beyond the side of the wafer stage 3 and is suspended above the drainage groove 2, with a horizontal distance between the edge of the square wafer 6 and the outer wall of the drainage groove 2. In a specific embodiment, the distance between the edge of the square wafer 6 protruding beyond the side of the wafer stage 3 is 1-3 mm, and the distance between the edge and the outer wall of the drainage groove 2 is ≥1 mm. This design of suspension and isolation distance cleverly breaks the capillary action condition required for liquid reflux in physical space, preventing the photoresist thrown out by centrifugal force from reversing and fundamentally solving the problem of high-viscosity adhesive backflow contaminating the back of the square wafer.
[0032] Building upon this, to further enhance the ability to prevent backside contamination, the wafer stage 3 of this application is also provided with an air vent 8. Specifically, the air vent 8 extends downwards from the side wall of the wafer stage 3 to the bottom of the carrier body 1. In a specific embodiment, the inclination angle of the air vent 8 is preferably 30°-60°, and the aperture is controlled between 0.3-0.8 mm.
[0033] In actual high-speed spin coating operations, the air vent 8, penetrating the bottom of the carrier plate 1, is connected to the positive pressure air source of the external spin coating equipment. During coating, positive pressure gas is continuously blown out from the opening on the side wall of the wafer stage 3, directly acting on the suspended area below the edge of the square wafer 6, forming a dynamic air curtain blowing outward. When the photoresist ejected by centrifugation attempts to undergo capillary recirculation on the side wall of the guide groove 2 or the edge of the wafer 6, this air curtain can actively blow the liquid outward and into the guide groove 2. This dual protection mechanism of "suspended physical isolation" plus "bottom active air curtain" greatly improves the yield of square wafer coating.
[0034] Continue to refer to Figure 2 As shown in the figure, a vacuum path structure for adsorbing wafers is provided on the wafer stage 3. This vacuum path structure is based on a central single-point evacuation and integrates a radial communication groove 7 and concentric nested vacuum grooves 5.
[0035] Specifically, at least two vacuum slots 5 are formed on the wafer stage 3. Each vacuum slot 5 is a square loop shape adapted to the outer contour of the wafer stage 3 and is arranged concentrically on the wafer stage 3. A negative pressure hole 4 is located at the center of the wafer stage 3, and a cross-shaped connecting slot 7 radiates outwards. The multiple square loop-shaped vacuum slots 5 arranged concentrically are interconnected through this cross-shaped connecting slot 7, forming a mesh-like radiating negative pressure gas path closed loop.
[0036] In a specific embodiment, the distance between the edge of the outermost vacuum trench and the edge of the square wafer 6 is strictly controlled to ≤5mm. The concentrically nested square loop vacuum trenches 5, the cross-shaped radial connecting trenches 7, and the negative pressure holes 4 together form a composite adsorption network, ensuring that the negative pressure adsorption force uniformly and firmly covers the entire back side of the square wafer.
[0037] Specifically, a main vacuum channel is provided through the central axis of the carrier plate body 1, and the bottom end of the negative pressure hole 4 is connected to the main vacuum channel for efficient connection with the rotary vacuum system of the external homogenizing equipment, so that the negative pressure generated by the external vacuum system is quickly and evenly transmitted to the vacuum tanks 5 of each level through the negative pressure hole 4 and the connecting groove 7.
[0038] Specifically, in combination Figure 1 and Figure 2 As shown, to achieve a stable mechanical connection between the carrier disk and external equipment, the wafer stage 3 is also provided with four screw mounting holes 9 penetrating the carrier disk body 1. In a specific embodiment, by tightening screws through the screw mounting holes 9, the entire carrier disk body 1 can be firmly locked onto the rotating spindle or receiving flange of the external coating equipment. This four-point symmetrical locking structure, combined with the mechanical positioning of the central main vacuum channel, not only ensures the physical connection strength of the carrier disk at extremely high speeds, but also maximizes the overall dynamic balance of mass during high-speed rotation, avoiding the negative impact of eccentric vibration on coating uniformity. At the same time, the layout of the screw mounting holes 9 cleverly avoids the vacuum air passage network composed of the vacuum groove 5, the connecting groove 7, and the negative pressure hole 4, ensuring the high airtightness of the carrier disk negative pressure adsorption system.
[0039] Example 1 A square-shaped adhesive-coated carrier disk, reference Figures 1-4 Its overall structure is as described in the aforementioned embodiment. In this embodiment, the specific dimensional parameters of each key component of the carrier disk are set as follows: The width of both the drainage port 201 and the auxiliary drainage port 202 is 8mm; the number of vacuum grooves 5 is 4; the distance between the edge of the outermost vacuum groove 5 and the edge of the square wafer 6 is controlled to be 3mm; the height difference between the upper surface of the square wafer 6 and the reference upper surface 101 of the periphery is set to 0.2mm; the distance between the edge of the square wafer 6 protruding from the side of the wafer stage 3 is 1mm; the distance between the edge of the square wafer 6 and the outer wall of the drainage groove 2 is 1mm; the diameter of the air blowing hole 8 is 0.3mm and the angle is 60°.
[0040] Example 2 A square-shaped adhesive-coated carrier tray, with the specific dimensional parameters of each key component of the carrier tray set as follows: The width of both the drainage port 201 and the auxiliary drainage port 202 is 10mm; the number of vacuum grooves 5 is 4; the distance between the edge of the outermost vacuum groove 5 and the edge of the square wafer 6 is controlled to be 4mm; the height difference between the upper surface of the square wafer 6 and the reference upper surface 101 of the periphery is set to 0.3mm; the distance between the edge of the square wafer 6 protruding from the side of the wafer stage 3 is 2mm, and the distance between the edge of the square wafer 6 and the outer wall of the drainage groove 2 is 2mm; the diameter of the air blowing hole 8 is 0.5mm and the angle is 45°.
[0041] Example 3 A square-shaped adhesive-coated carrier tray, with the specific dimensional parameters of each key component of the carrier tray set as follows: The width of both the drainage port 201 and the auxiliary drainage port 202 is 12mm; the number of vacuum grooves 5 is 4; the distance between the edge of the outermost vacuum groove 5 and the edge of the square wafer 6 is controlled to be 5mm; the height difference between the upper surface of the square wafer 6 and the reference upper surface 101 of the periphery is set to 0.5mm; the distance between the edge of the square wafer 6 protruding from the side of the wafer stage 3 is 3mm; the distance between the edge of the square wafer 6 and the outer wall of the drainage groove 2 is 3mm; the diameter of the air blowing hole 8 is 0.8mm and the angle is 30°.
[0042] Comparative Example 1 A square-shaped adhesive-coated carrier tray, with the specific dimensional parameters of each key component of the carrier tray set as follows: The width of both the drainage port 201 and the auxiliary drainage port 202 is 5mm; the number of vacuum grooves 5 is 4; the distance between the edge of the outermost vacuum groove 5 and the edge of the square wafer 6 is controlled to be 2mm; the height difference between the upper surface of the square wafer 6 and the reference upper surface 101 of the periphery is set to 0mm; the distance between the edge of the square wafer 6 protruding from the side of the wafer stage 3 is 2mm, and the distance between the edge of the square wafer 6 and the outer wall of the drainage groove 2 is 2mm.
[0043] Comparative Example 2 A square-shaped adhesive-coated carrier tray has a width of 10mm for both the inlet 201 and the additional inlet 202; four vacuum grooves 5; the distance between the edge of the outermost vacuum groove 5 and the edge of the square wafer 6 is controlled to be 4mm; the height difference between the upper surface of the square wafer 6 and the reference upper surface 101 of the periphery is set to 0.3mm; the distance between the edge of the square wafer 6 protruding from the side of the wafer stage 3 is 2mm; the distance between the edge of the square wafer 6 and the outer wall of the inlet groove 2 is 2mm; and there are no air blowing holes.
[0044] The carrier disks provided in Examples 1-3 and Comparative Examples 1-2 were subjected to standard high-speed spin-coating photoresist tests, and the test methods are as follows: Standard square wafers 6 of the same specifications were placed on the carrier bodies 1 of Examples 1-3 and Comparative Examples 1-2, respectively, and the main vacuum channel was turned on for negative pressure adsorption. Uniform spin coating process parameters were set (rotation speed 1500 rpm, coating time 30 s) for photoresist spin coating. After spin coating, the wafers were removed, and the coating status and carrier state were observed and recorded.
[0045] Test and observation items: The thickness difference between the central region and the four edge / corner regions of a square wafer was measured using a film thickness meter to assess the degree of interference of edge cutting airflow (wind shear effect) on film uniformity.
[0046] Flip the wafer over and observe whether there is any contamination caused by the photoresist being sucked back and rolled up due to capillary action on the back edge and the four corner areas.
[0047] Observe the drain port 201, the additional drain port 202, and the dead corners of the drain groove 2 on the carrier disk to see if there is a large amount of photoresist remaining or dried up.
[0048] Observe whether high-frequency vibration or slight warping occurs in the four corners and edge areas of the square wafer under high-speed centrifugal force.
[0049] The test results are shown in Table 1.
[0050] Table 1 Summary of adhesive application results for Examples 1-3 and Comparative Examples 1-2 As shown in Table 1, the difference between the edge adhesive height and the center adhesive thickness in Examples 1-3 is small, and the wafer edge flatness is controlled within an excellent range of 8%-12%. This is the result of the synergistic effect of multiple structural features: on the one hand, the 0.2mm-0.5mm stepped height difference successfully creates a flow-blocking microenvironment above the wafer, effectively eliminating the wind shearing effect; on the other hand, the distance between the outermost vacuum groove and the wafer edge is controlled within 3-5mm, providing sufficient mechanical anchoring force for the suspended edge most susceptible to airflow interference, preventing micro-warping or high-frequency vibration of the wafer at high speeds. In contrast, in Comparative Example 1, there is no height difference between the upper surface of the square wafer and the reference upper surface of the periphery. The apex of the square wafer faces the external airflow cutting directly during rotation, causing the edge adhesive height to surge to 1050nm and the uniformity to deteriorate drastically to 50%. This fully demonstrates the necessity of height difference flow blocking combined with nearby vacuum anchoring in ensuring the quality of edge film formation.
[0051] Regarding backside contamination control, Examples 1-3 all achieved an ideal state of no contamination. Comparative Example 2, while also possessing a height difference and isolation spacing, lacked air vents. Test results showed that, without the bottom active positive pressure air curtain to block it, physical suspension alone was insufficient to completely resist centrifugal gravity and the complex fluid dynamics at tiny gaps, leading to severe contamination in Comparative Example 2. This comparison strongly demonstrates that the downward-sloping air vents added to the sidewalls in this application, combined with the physical isolation spacing, create an excellent dynamic-static synergistic effect, representing a key technological barrier to completely eliminate photoresist capillary backflow and contamination.
[0052] In Examples 1-3, the width of the drainage port and additional drainage port was within the range of 8-12mm, and all tests showed no adhesive buildup and smooth drainage. However, the drainage port width of Comparative Example 1 was only 5mm, which could not meet the instantaneous drainage requirements of the large amount of photoresist collected at the corner, resulting in obvious adhesive buildup at the drainage port of the carrier tray and in the dead corners at the bottom of the tank.
[0053] The specific embodiments of this application have been described above, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.
Claims
1. A square-shaped adhesive-coated carrier disk, comprising a carrier disk body, characterized in that, The carrier disk body is provided with an annular drainage groove, which divides the carrier disk body into an inner central part and an outer peripheral part. The central part forms a wafer stage with a square outer contour. The wafer stage is provided with a negative pressure hole, a blow hole and a vacuum groove. The peripheral portion has a reference upper surface, the stage of the wafer stage is lower than the reference upper surface of the peripheral portion, and the bottom surface of the drainage groove is lower than the stage of the wafer stage; The drainage grooves extend outward from the outer periphery along the diagonal direction of the wafer stage, forming drainage ports that penetrate the outer edge of the outer periphery; the center line of the extension of the drainage port is aligned with the apex corner of the square wafer placed on the wafer stage. The upper surface of the square wafer placed on the wafer stage is lower than the reference upper surface of the peripheral portion; The edge of the square wafer protrudes from the side of the wafer stage and is suspended above the drainage groove, and there is a horizontal distance between the edge of the square wafer and the outer wall of the drainage groove. The air vent extends downwards from the side wall of the wafer stage to the bottom of the carrier disk body.
2. The square-shaped adhesive-coated carrier disk according to claim 1, characterized in that, Multiple additional drainage ports are also provided, which are provided on the side of the wafer stage and extend from the drainage groove to the outside of the carrier body and through the edge of the carrier body; the multiple additional drainage ports are symmetrically distributed on the carrier body.
3. The square-shaped adhesive-coated carrier disk according to claim 2, characterized in that, The bottom surfaces of the drainage port and the additional drainage port are flush with the bottom surface of the drainage channel.
4. The square-shaped adhesive-coated carrier disk according to claim 3, characterized in that, The width of both the drainage port and the additional drainage port is 8-12mm.
5. The square-shaped adhesive-coated carrier disk according to claim 1, characterized in that, The inclination angle of the air inlet is 30°-60°.
6. The square-shaped adhesive-coated carrier disk according to claim 1, characterized in that, The number of vacuum slots is at least two, and each vacuum slot is a square loop shape adapted to the outer contour of the wafer stage, and is arranged in a concentric nested manner on the wafer stage.
7. The square-shaped adhesive-coated carrier disk according to claim 6, characterized in that, The negative pressure hole is located at the center of the wafer stage. The wafer stage is also provided with a connecting groove radiating outward from the negative pressure hole. Multiple vacuum grooves arranged in a concentric nested manner are interconnected through the connecting groove.
8. The square-shaped adhesive-coated carrier disk according to claim 6, characterized in that, The distance between the outermost edge of the vacuum tank and the edge of the square wafer is ≤5mm.
9. The square-shaped adhesive-coated carrier disk according to claim 1, characterized in that, The height difference between the upper surface of the square wafer and the reference upper surface of the peripheral portion is ≥0.2mm.
10. The square-shaped adhesive-coated carrier disk according to claim 1, characterized in that, The distance by which the edge of the square wafer protrudes beyond the side of the wafer stage is 1-3 mm, and the distance between the edge of the square wafer and the outer wall of the drainage groove is ≥1 mm.