Planarization process, apparatus, and method of manufacturing an article

Abstract

A method is provided that includes creating at least one crack at a location on an edge of a stack of at least a substrate and a superstrate; propagating the crack along the perimeter; and moving the superstrate relative to the substrate to complete separation of the superstrate from the substrate.

Description

Technical Field

[0001] This disclosure relates to substrate processing, and more specifically to surface flattening in semiconductor manufacturing. Background Technology

[0002] Planarization techniques can be used in the fabrication of semiconductor devices. For example, processes for manufacturing semiconductor devices involve repeatedly adding and removing material from a substrate. This process can produce layered substrates with irregular height variations (i.e., morphology), and the height variation increases with the addition of more layers. Height variations negatively impact the ability to add more layers to a layered substrate. Furthermore, semiconductor substrates (e.g., silicon wafers) are not always perfectly flat and may include initial surface height variations (i.e., morphology). One approach to address this problem is to planarize the substrate between layering steps. Various photolithographic patterning methods benefit from patterning on flat surfaces. In ArFi laser-based lithography, planarization improves depth of focus (DOF), critical dimension (CD), and critical dimension uniformity. In extreme ultraviolet (EUV) lithography, planarization improves feature placement and DOF. In nanoimprint lithography (NIL), planarization improves feature fill and CD control after pattern transfer.

[0003] Planarization techniques, sometimes referred to as inkjet-based adaptive planarization (IAP), involve distributing a variable droplet pattern of polymerizable material between a substrate and a cover plate, where the droplet pattern varies according to the substrate morphology. The cover plate is then brought into contact with the polymerizable material, which subsequently polymerizes on the substrate, and the cover plate is removed. Improvements to planarization techniques, including IAP, are needed to enhance applications such as monolithic wafer fabrication and semiconductor device manufacturing. Summary of the Invention

[0004] A method is provided. The method includes generating at least one crack at a location on an edge of a stack of at least a substrate and a cover plate, extending the crack along a periphery, and moving the cover plate relative to the substrate to complete separation of the cover plate from the substrate. The method may further include introducing a positive fluid pressure at the location on the edge between the substrate and the cover plate to generate the crack. The positive fluid pressure includes a stream of clean, dry air, a stream of helium, or a stream of nitrogen. The method may further include holding the cover plate in a cover plate chuck with a negative fluid pressure and applying a high flow of the negative fluid pressure to a peripheral section on the cover plate to extend the crack along the edge of the stack.

[0005] While applying a high flow of negative fluid pressure to the peripheral sections of the cover plate, positive fluid pressure is continued to be introduced into the separation section. The cover plate can be moved away from the substrate using a cover plate chuck. The method may also include applying negative fluid pressure to the central section of the cover plate to complete the separation of the cover plate from the substrate using a cover plate chuck. The method may also include applying force at the location on the edge of the cover plate to create the crack. Another crack can be created by applying positive fluid pressure between the substrate and the cover plate at another location on the edge of the stack. The force can be applied by introducing positive fluid pressure or mechanical contact.

[0006] The method may further include stacking the substrate and the cover plate such that the cover plate includes a hanging edge portion; and applying a force to the hanging edge portion to create a crack. Another edge portion of the cover plate may be aligned with a notch at an edge portion of the substrate, and a force may be applied to the other edge portion to create another crack between the substrate and the cover plate.

[0007] A clamping system is also provided. The system includes a cover plate chuck configured to hold a cover plate with negative fluid pressure and a force source configured to apply force to a portion at an edge of the cover plate stacked with a substrate, thereby creating a crack between the substrate and the cover plate at the portion at the edge. The cover plate chuck includes a pattern of groove banks, and one of the groove banks located near the edge of the cover plate chuck is recessed below other groove banks located internally within the cover plate chuck to allow the cover plate to deflect toward the cover plate chuck while creating the crack. The clamping system may further include a substrate chuck configured to hold the substrate with negative fluid pressure. The substrate chuck includes a pattern of groove banks, and one of the groove banks located at the edge of the substrate chuck is recessed below other groove banks located internally within the substrate chuck to allow the substrate to deflect toward the substrate chuck while creating the crack.

[0008] The force source includes a mechanism for generating lateral mechanical thrust or a positive fluid pressure source toward the edge of the cover plate. The substrate includes a notch disposed at its edge, and the force source includes a negative fluid pressure source applied to the cover plate via the notch. The clamping system may further include a negative fluid pressure source for applying negative fluid pressure to the cover plate via the cover plate chuck. The cover plate chuck is configured to hold the cover plate such that the cover plate includes an overhanging portion. The force source is configured to apply force to the overhanging portion of the cover plate to create the crack.

[0009] A method for manufacturing an article is provided. The method includes forming a cured material stacked between a substrate and a cover plate; generating at least one crack at a location at an edge between the substrate and the cover plate; extending the crack along a periphery; and separating the cover plate from the cured material.

[0010] Various objects, features, and advantages of this disclosure will become apparent when the following detailed description of exemplary embodiments of this disclosure is read in conjunction with the accompanying drawings and the provided claims. Attached Figure Description

[0011] The embodiments of the invention can be described in more detail by referring to the examples shown in the accompanying drawings, so that the features and advantages of the invention can be understood in detail. However, it should be noted that the drawings only illustrate typical embodiments of the invention and should not be considered as limiting its scope; other equivalent and effective embodiments are permissible.

[0012] Figure 1 This is a diagram showing the leveling system;

[0013] Figures 2A to 2C The leveling process is shown;

[0014] Figures 3A to 3B A multi-zone overlay chuck is shown in one embodiment;

[0015] Figures 4A to 4E The operation of a cover plate chuck for forming a layer on a substrate is shown;

[0016] Figure 5 yes Figures 4A to 4E The flowchart of the leveling process shown;

[0017] Figure 6A A separation crack is shown at the edge of the stack of the substrate and the cover plate in one embodiment, and Figure 6B The alignment of the retractable pin used to induce this separation crack with the substrate notch is shown.

[0018] Figure 6C A separation crack is shown at the edge of the stack of the substrate and the cover plate in another embodiment;

[0019] Figures 7A to 7C A top view of the stack of substrate and cladding is shown as separation cracks are initiated and extend around the periphery of the stack.

[0020] Figure 8 The separate substrate and cover plate are shown;

[0021] Figure 9 This is a flowchart of the separation process shown in Figures 7 and 8;

[0022] Figure 10 A separation crack is shown at the edge of the stack of the substrate and the cover plate in another embodiment;

[0023] Figure 11A and 11B A multi-zone chuck with improved zone sealing is shown in another embodiment; and

[0024] Figure 12 It shows Figure 11A and 11B An enlarged view of an exemplary groove structure within the partition of the cover plate chuck.

[0025] Throughout the accompanying drawings, unless otherwise stated, the same reference numerals and characters are used to denote similar features, elements, components, or portions of the illustrated embodiments. Furthermore, although this disclosure will now be described in detail with reference to the accompanying drawings, this is done in conjunction with illustrative exemplary embodiments. Modifications and variations of the described exemplary embodiments may be made without departing from the true scope and spirit of this disclosure as defined by the appended claims. Detailed Implementation

[0026] Leveling system

[0027] Figure 1 A system for leveling is shown. The leveling system 100 is used to level the film on a substrate 102. The substrate 102 can be coupled to a substrate chuck 104. The substrate chuck 104 can be, but is not limited to, a vacuum chuck, a pin chuck, a groove chuck, an electrostatic chuck, an electromagnetic chuck, etc.

[0028] The substrate 102 and substrate chuck 104 can be further supported by the substrate positioning stage 106. The substrate positioning stage 106 can provide support along the x, y, z, θ, ψ and Translational and / or rotational movements of one or more axes. The substrate positioning stage 106, substrate 102, and substrate chuck 104 may also be positioned on a base (not shown). The substrate positioning stage may be part of a positioning system.

[0029] Spaced apart from the substrate 102 is a cover plate 108, which has a working surface 112 facing the substrate 102. The cover plate 108 may be formed of materials including, but not limited to, fused silica, quartz, silicon, organic polymers, siloxane polymers, borosilicate glass, fluorocarbon polymers, metals, hardened sapphire, etc. In embodiments, the cover plate is readily transparent to ultraviolet light (UV light). Surface 112 typically has the same or slightly smaller area dimensions as the surface of the substrate 102.

[0030] The cover plate 108 may be coupled to or held by the cover plate chuck 118. The cover plate chuck 118 may be, but is not limited to, a vacuum chuck, a pin chuck, a grooved chuck, an electrostatic chuck, an electromagnetic chuck, and / or other similar chuck types. The cover plate chuck 118 may be configured to apply varying stresses, pressures, and / or strains to the cover plate 108. In embodiments, the cover plate chuck is also readily transparent to UV light. The cover plate chuck 118 may include systems such as partition-based vacuum chucks, actuator arrays, pressure balloons, etc., which can apply a pressure differential to the rear surface of the cover plate 108 to induce bending and deformation of the template. In one embodiment, the cover plate chuck 118 includes a partition-based vacuum chuck that can apply a pressure differential to the rear surface of the cover plate to induce bending and deformation of the cover plate, as further detailed herein.

[0031] The cover plate chuck 118 can be coupled to a leveling head 120 as part of a positioning system. The leveling head 120 can be movably coupled to a bridging member. The leveling head 120 may include one or more actuators, such as voice coil motors, piezoelectric motors, linear motors, nut and screw motors, etc., configured at least in the z-axis direction and possibly other directions (e.g., x, y, θ, ψ, and...). The cover plate chuck 118 moves relative to the substrate 102 on the axis.

[0032] The leveling system 100 may also include a fluid dispenser 122. The fluid dispenser 122 is also movably coupled to a bridging member. In one embodiment, the fluid dispenser 122 and the leveling head 120 share one or more of all positioning components. In an alternative embodiment, the fluid dispenser 122 and the leveling head move independently of each other. The fluid dispenser 122 can be used to deposit droplets of a liquid formable material 124 (e.g., a photocurable polymerizable material) onto a substrate 102, wherein the volume of the deposited material varies at least partially based on its topographic profile over a region of the substrate 102. Different fluid dispensers 122 may use different techniques to dispense the formable material 124. When the formable material 124 is jettable, an inkjet dispenser may be used to dispense the formable material. For example, thermal inkjet, microelectromechanical system (MEMS) based inkjet, valve jet, and piezoelectric inkjet are common techniques for dispensing jettable liquids.

[0033] The planarization system 100 may further include a curing system comprising a radiation source 126 that directs photochemical energy (e.g., UV radiation) along an exposure path 128. The planarization head 120 and substrate positioning stage 106 may be configured to position the cover plate 108 and substrate 102 to overlap with the exposure path 128. After the cover plate 108 has contacted the formable material 124, the radiation source 126 delivers photochemical energy along the exposure path 128. Figure 1The exposure path 128 is shown when the cover plate 108 is not in contact with the formable material 124. This is done for illustrative purposes so that the relative positions of the various components can be easily identified. Those skilled in the art will understand that the exposure path 128 remains substantially unchanged when the cover plate 108 is in contact with the formable material 124.

[0034] The leveling system 100 may also include a camera 136, which is positioned to observe the diffusion of the formable material 124 during the leveling process when the cover plate 108 contacts the formable material 124. Figure 1 The optical axis 138 of the imaging field of the on-site camera is shown. For example... Figure 1 As shown, the planarization system 100 may include one or more optical components (dichroic mirrors, beam combiners, prisms, lenses, mirrors, etc.) that combine photochemical radiation with light to be detected by the camera 136. The camera 136 may include one or more of a CCD, sensor array, linear camera, and photodetector, configured to collect light of a specific wavelength to display the contrast between the area below the cover plate 108 and in contact with the formable material 124 and the area below the cover plate 108 but not in contact with the formable material 124. The camera 136 may be configured to provide an image of the diffusion of the formable material 124 below the cover plate 108 and / or an image of the separation of the cover plate 108 from the cured formable material 124. The camera 136 may also be configured to measure interference fringes that change as the formable material 124 diffuses between the surface 112 and the substrate surface.

[0035] The leveling system 100 can be regulated, controlled, and / or guided by one or more processors 140 (controllers) communicating with one or more components and / or subsystems (e.g., substrate chuck 104, substrate positioning stage 106, cover plate chuck 118, leveling head 120, fluid distributor 122, radiation source 126, and / or camera 136). The processors 140 can operate based on instructions in a computer-readable program stored in non-transitory computer memory 142. The processor 140 can be or may include one or more of a CPU, MPU, GPU, ASIC, FPGA, DSP, and general-purpose computer. The processor 140 can be a dedicated controller or a general-purpose computing device suitable as a controller. Examples of non-transitory computer-readable memory include, but are not limited to, RAM, ROM, CD, DVD, Blu-ray storage, hard disk drive, network-attached storage (NAS), intranet-connected non-transitory computer-readable storage devices, and internet-connected non-transitory computer-readable storage devices.

[0036] In operation, the leveling head 120, the substrate positioning stage 106, or both of these alter the distance between the cover plate 108 and the substrate 102 to define a desired space (a three-dimensional bounded physical area) to be filled with the formable material 124. For example, the leveling head 120 may move toward the substrate and apply force to the cover plate 108 such that the cover plate contacts and diffuses droplets of the formable material 124, as further detailed herein.

[0037] leveling process

[0038] The leveling process includes Figure 2A-2C The steps are illustrated schematically. For example... Figure 2A As shown, the formable material 124 is dispensed onto the substrate 102 in the form of droplets. As previously described, the substrate surface has a certain morphology, which can be known based on previous processing operations or measured using a profilometer, AFM, SEM, or an optical surface profilometer based on optical interference effects (such as the ZygoNewViEw 8200). The local bulk density of the deposited formable material 124 varies depending on the substrate morphology. A cover plate 108 is then positioned to contact the formable material 124.

[0039] Figure 2B The diagram illustrates a post-contact step after the cover plate 108 has fully contacted the formable material 124, but before the polymerization process begins. When the cover plate 108 contacts the formable material 124, droplets coalesce to form a formable material film 144 filling the space between the cover plate 108 and the substrate 102. Preferably, the filling process is carried out uniformly without any air or bubbles being trapped between the cover plate 108 and the substrate 102 to minimize unfilled defects. The polymerization process or curing of the formable material 124 can be initiated using photochemical radiation (e.g., UV radiation). For example, Figure 1 The radiation source 126 can provide photochemical radiation that causes the formable material film 144 to cure, solidify, and / or crosslink, thereby defining a cured planarization layer 146 on the substrate 102. Alternatively, curing of the formable material film 144 can also be initiated by using heat, pressure, chemical reaction, other types of radiation, or any combination of these methods. Once the cured planarization layer 146 is formed, the cover plate 108 can be separated from it. Figure 2C A cured planarization layer 146 is shown on the substrate 102 after the separation of the cover plate 108. Further known steps and processes for device (article) manufacturing can then be performed on the substrate and the cured layer, including, for example, patterning, curing, oxidation, layer formation, deposition, doping, planarization, etching, removal of formable material, cutting, bonding, and encapsulation. The substrate can be processed to produce multiple articles (devices).

[0040] Diffusion, filling, and curing of leveling material between the cover plate and the substrate.

[0041] When the formable material droplets diffuse, coalesce, and fill the gap between the cover plate and the substrate, one approach to minimize the trapping of air or bubbles between the cover plate 108 and the substrate is to position the cover plate so that it makes initial contact with the formable material at the center of the substrate, followed by further contact radially from the center to the periphery. This requires the cover plate or the substrate, or both, to deflect or bend to form a curvature profile in the cover plate. However, given that the cover plate 108 typically has the same or similar area dimensions as the substrate 102, an effective overall cover plate bend profile requires both significant vertical deflection of the cover plate and accompanying vertical movement of the cover plate chuck and flattening assembly. Such significant vertical deflection and movement may be undesirable for control, accuracy, and system design considerations. For example, such a cover plate profile can be obtained by applying back pressure to an internal region of the cover plate. However, in doing so, a peripheral holding region is still required to hold the cover plate on the cover plate chuck. If the peripheral edges of the cladding and substrate are clamped flat during the diffusion and coalescence of the formable material droplets, no cladding curvature profile will be available in the flat clamped area. This may hinder droplet diffusion and coalescence, potentially leading to unfilled defects in the area. Furthermore, once the diffusion and filling of the formable material is complete, the resulting stack of cladding chuck, clamped cladding, formable material, substrate, and substrate chuck may be an over-constrained system. This can result in an uneven flat profile in the resulting flat film layer. In other words, in such an over-constrained system, all flatness errors or variations from the cladding chuck (including front and rear surface flatness) may be transmitted to the cladding and affect the uniformity of the flat film layer.

[0042] To address the above issues, in one embodiment, the following is provided: Figure 3A and 3B The multi-zone cover chuck 118 is shown. The cover chuck 118 includes a central zone 301 and a series of annular zones 303 surrounding the central zone 301. The annular zones 303 can be defined as peripheral annular zones 303b surrounding the edge, perimeter, or periphery of the cover chuck 118, and a plurality of inner annular zones 303a located between the central zone 301 and the peripheral annular zones 303b. The plurality of annular zones 303 can be defined by a series of grooves 307 protruding from the surface of the cover chuck 118. Figure 3A and 3B As shown, the trough bank 307 may be formed around the central section 301. In each ring section 303, at least one port 305 is formed for connection via a cover plate chuck 118 to allow a pressure source to apply positive or negative pressure (e.g., vacuum) to the cover plate held thereby.

[0043] Figure 3BA side cross-sectional view of the cover plate chuck 118 is shown. Each groove bank 307 protrudes a certain height from the surface of the cover plate chuck 118. The groove banks 307 include a peripheral groove bank 307b surrounding the peripheral ring section 303b and a series of inner groove banks 307a between the central section 301 and the peripheral ring section 303b. Figure 3B As shown, the inner groove banks 307a have substantially the same height, while the peripheral groove banks 307b have a lower height than the inner groove banks 307a. The central section 301 of the cover chuck 118 can be in the form of a circular cavity, such that a pressure source (not shown) can apply air or gas pressure through associated channels 308 and ports 305 to deflect the central portion of the held cover. Vacuum pressure can be similarly applied to the central section 301 through the same channels and ports. The central section 301 of the cover chuck 118 can be aligned with the central portion of the held cover. Similarly, the peripheral annular section 303a can be aligned with the perimeter or circumference of the held cover. Corresponding channels 308 and ports 305 for applying pressure or vacuum are similarly provided around the annular section 303.

[0044] Turning Figures 4A-4E This illustrates the process for contacting, diffusing, and merging droplets of deposited shapeable material 124. (Example) Figure 4A As shown, before the cover plate 108 comes into contact with the formable material 124, a positive pressure (indicated by arrow P) is applied to the held cover plate 108 through port 305 of the center partition 301 of the cover plate chuck 118 to deflect the center portion of the cover plate 108 toward the formable material 124. Pressure P is applied to the center partition 301 to control the initial deflection within a predetermined range and maintain a predetermined curvature of the cover plate 108, such as... Figure 4A As shown in the diagram. Simultaneously, a negative pressure, preferably a vacuum (indicated by arrow V), is applied to the cover plate 108 through port 305 in the annular partition 303 to hold the cover plate 108 in place with the cover plate chuck 118. The cover plate 108 is then brought into initial contact with droplets of the formable material 124, as shown in the diagram. Figure 4B As shown in the image.

[0045] Then, by sequentially releasing the vacuum (V) from the inner ring partition 303a near the central partition 301, the deflection of the cover plate 108 extends radially outward from the central portion. In this way, droplets of formable material contact, diffuse, and merge to form a film layer with a fluid front that advances radially outward as the cover plate contacts and conforms to the substrate. The pressure P applied through the central partition 301 is maintained at a desired value when the vacuum is sequentially released from the inner ring partition 303a. The pressure P can also be applied to the cover plate 108 through the channels 308 and ports 305 in the inner ring partition 303a, where the vacuum has been released. Figure 4CIn the illustrated embodiment, vacuum has been sequentially released from the three inner rings 303a closest to the inner partition 301, and pressure P has been sequentially applied as the vacuum has been sequentially released. The leveling head may also move downwards during this sequential vacuum release and pressurization.

[0046] The deflection of the cover plate 108 then extends sequentially further in the radial direction until the vacuum is released from all inner ring sections 303a, while maintaining the vacuum V applied via the peripheral ring sections 303b. For each inner ring section 303a, once the vacuum has been released, a pressure P is also applied. Figure 4D As shown, when the vacuum has been released from all inner ring sections 303a, the cover plate 108 deflects to conform to the substrate 102, except for the periphery of the substrate 108 still held by the substrate chuck 104 via the vacuum V applied through the peripheral section 303b. Thus, the edges of the cover plate 108 remain in a deflected, curved state for the final diffusion and coalescence of the formable material droplets distributed on the periphery of the substrate 102. Furthermore, the peripheral trench bank 307b, lowered relative to the inner trench bank 307a, helps maintain this curvature.

[0047] exist Figure 4E In this process, the vacuum V applied through the peripheral ring partition 303b is then released to completely release the cover plate 108 from the cover plate chuck 118. This provides several advantages. First, by releasing the periphery of the cover plate 108 from the peripheral ring partition 303b, which was originally held in a curved state, the diffusion and merging of remaining formable material droplets can be completed in the same radial manner from center to periphery, thereby continuing to minimize air or gas trapping and the resulting unfilled defects. Specifically, the peripheral groove bank 307b, which is recessed relative to the inner groove bank 307a, allows the cover plate 108 to maintain the desired curvature before release. Second, by completely releasing the cover plate 108 from the cover plate chuck 118, any excessive constraint on the cover plate 108 due to the clamping state is removed, thereby reducing local non-uniform flatness that might otherwise occur due to such a constrained state. Third, releasing the cover plate 108 from the cover plate chuck 118 eliminates any transfer of chuck non-flatness errors or variations to the cover plate 108, which also reduces local non-uniform flatness variations.

[0048] Once the cover plate 108 is released, curing energy can be applied to cure the formable material to form a planarized layer. As previously described, the curing source can be a light beam used to cure the formable material 124. In one embodiment, the size of the light beam can be adjusted or controlled with reference to the diameter of the cover plate. The light beam can also be controlled to be incident on the substrate at a predetermined angle. During curing, the lateral position of the substrate 102 relative to the curing source (i.e., in the XY plane) can be adjusted. After the curing process, as further described herein, the cover plate 108 is re-held by the cover plate chuck 118 and the cover plate 108 is subsequently separated from the substrate.

[0049] Figure 5 A flowchart of the flattening process, as shown in Figures 3 and 4, is illustrated. In step S501, a droplet 124 of formable material is dispensed onto a substrate 102. In step S502, the central section of a cover plate 108 is deflected toward the droplet 124 of formable material. In step S503, the deflected cover plate 108 is then advanced by a cover plate chuck 118 into contact with the formable material 124. In step S504, the deflection of the cover plate 108 extends from the central section toward the periphery of the cover plate 108. Then, in step S506, the force applied by the cover plate chuck 118 to hold the cover plate 108 (e.g., by applying a vacuum to the periphery of the cover plate 108) is stopped, so that the cover plate 108 is released from the cover plate chuck 118 (i.e., unjawed). In step S507, the formable material 124 is cured. After curing, the cover plate 108 is held back by the cover plate chuck 118 to separate the cover plate 108 from the cured formable material 146.

[0050] When, for example, a UV-curable material is used as the formable material 124, it is desirable that the cover plate chuck 118 is transparent and has high UV light transmittance during UV curing (and for imaging, for example, by means of...). Figure 1 The camera 136 shown has high light transmittance for imaging. As described above, the pneumatic supply channel 308 and port 305, partition 303, and trench bank 307 are integrated into the cover plate, as shown in Figures 3 and 4. These structures can cause problems for UV curing. In particular, the UV transmittance in the area below the channel 308 and trench bank 307 may be significantly reduced compared to areas without such features, resulting in insufficient or uneven curing of the formable material. This phenomenon is sometimes referred to as the "shadowing effect." The shadowing effect may be particularly pronounced at the edges of the trench bank 307. Additionally, when the cover plate 100 is clamped to the trench bank 307, a thin air gap will exist because the two surfaces are not optically in contact with each other. This type of thin gap may sometimes completely block UV light. This phenomenon is called the "thin film effect" between the trench bank and the cover plate.

[0051] One solution to the aforementioned “shadowing effect” involves moving the stack of the cover plate and substrate on the wafer stage according to x, y, and / or θ coordinates after the cover plate is unhooked (i.e., released) from the cover plate chuck. By moving the wafer stage in this manner during UV exposure, areas of the cover plate and substrate that should remain below the channels, ports, and trench banks can be periodically moved to areas below the cover plate chuck where no chuck features exist. The required relative motion can be estimated using the following formula (1):

[0052]

[0053] Among them, I mIt is the expected average intensity within the range of motion, I h It is the high intensity (i.e., the maximum or "maximum") on the featureless area of ​​the chuck, I l It is the intensity at the object's feature (i.e., the lowest value or "low" intensity), w h Is to reach I m The estimated range of motion, w l This refers to the width of the object's features (e.g., the width of a trench, port, or channel). For example, assuming the UV transmittance in a featureless region is 100%, and assuming the desired I... m It is 90% of that value, and further assumes w i =1mm, then according to formula (1), the expected relative motion range w h = 8.0 mm. Alternatively, the UV source can be moved relative to the cover plate chuck to change the angle of the UV light incident on the cover plate chuck, which can also reduce shading effects near object features. The “thin film effect” can be avoided by relative movement along the z-axis (e.g., by unclamping the cover plate and moving the wafer stage away from the cover plate chuck in the z-direction) to create sufficient clearance between the cover plate and the cover plate chuck. The various solutions described above can be applied individually or in combination to improve the overall UV dose uniformity in certain areas and minimize shading and thin film effects. In various embodiments, the applied UV beam can be smaller, the same size, or larger than the substrate or cover plate. In one embodiment, the applied UV beam can be a certain size larger than the substrate to accommodate the aforementioned relative movement while continuously exposing the entire substrate to UV light. h .

[0054] Separate the coating from the cured and flattened film layer

[0055] Once the formable material has cured and formed a flat film layer, the cladding must be removed or released from the formed layer. However, when the cladding and substrate have the same or similar area dimensions, it is difficult to initiate and propagate separation cracks between the cladding and the formed layer, which is necessary for complete separation of the cladding from the formed layer. This problem can be solved by the structure and method shown in Figures 6-8. Figure 6A and 6B As shown, the substrate chuck 604 includes a retractable pin 606 located at the periphery of the chuck, which can be aligned with a notch 608 on the substrate 102. Such notches (e.g., wafer notches) are common for semiconductor wafers and are intended to orient the wafer during processing and handling. In operation, the retractable pin 606 is positioned to align with the notch 608 on the substrate 102. To initiate separation, the pin 606 moves upward through the notch 608 and contacts a portion 610 at the edge of the cover plate 108, as... Figure 6AAs shown in the diagram. The force applied by pin 606 is sufficient to induce a separation crack 601 between the cured layer 146 on the cover plate 108 and the substrate 102. Once the crack 601 is generated, the edge of the cover plate 108 is deflected toward the cover plate chuck 118 by applying vacuum pressure through port 305 of the cover plate chuck 118. This deflection is facilitated by the fact that the groove bank 307b of the cover plate chuck 118 is shorter than the adjacent groove bank 307a, which provides space for the edge of the cover plate 108 to deflect away from the substrate 102 and toward the cover plate chuck 118. The force applied to generate the crack 601 can depend on the geometry and physical conditions of the cover plate, the planarization film layer, and the substrate. Alternatively, the crack 601 can be generated by introducing a positive pressure between the substrate 102 and the cover plate 108, as shown in the diagram. Figure 6C As shown. Here, the base plate chuck 614 includes a nozzle 616 connected to a positive fluid pressure source (not shown). Once the nozzle 616 is activated, the positive fluid pressure P... I The fluid is delivered through nozzle 616 to the edge of the cover plate 118 at portion 610 to induce a separation crack 601 with sufficient force. The positive fluid pressure may include a stream of clean, dry air, a stream of helium, or a stream of nitrogen. While the crack 601 is being created, the cover plate 102 is held in the cover plate chuck 118, and the substrate 102 is held by the substrate chuck 104.

[0056] Figures 7-8 show the progress of the separation. Figure 7A A top view is shown of a cover plate 118 that is in complete contact with a layer formed on a substrate (as shown in the shaded area). Figure 7B As described above, a separation crack 601 has been induced. Once crack 601 is induced, a high flow or vacuum under negative pressure is applied to the outer annular partition 303b of the cover plate chuck 118 to engage the edge of the cover plate 108 and extend the separation crack 601 around the outer annular partition 303b. This extension proceeds circumferentially in two directions from the notch 608, as indicated by arrow C. To aid in the extension of crack 601 around the outer annular partition 303b, additional lateral airflow (not shown) can be supplied between the substrate 102 and the cover plate 108 as the crack extends. Figure 7C The crack 601 is shown to be fully extended around the outer ring partition 303b.

[0057] Once the separation crack has fully expanded around the outer ring partition, an upward movement can be applied along the Z-axis direction of the cover plate 108 to complete the separation of the cover plate 108 from the cured layer on the substrate. Figure 8A cover plate 108 completely separated from the substrate 102 is shown. Upon completion of separation, the significant upward movement of the cover plate 108 relative to the substrate 102 can induce shear stress in the remaining contact area between the cover plate 108 and the substrate 102. Alternatively, movement in the Z direction can be stopped at an earlier desired location, and separation can be advanced and terminated by continuously applying vacuum pressure to the inner ring partition and / or the central ring partition. This shear stress can be minimized by applying a vacuum to one or more inner ring partitions 303a and / or the central partition 301 during continuous separation.

[0058] Figure 9 As shown in Figure 7 and Figure 8 The flowchart of the separation process described and shown is as follows. In step S901, a separation crack is initiated between the cover plate 108 and the cured layer. Then, in step S902, the separation crack is extended around the periphery of the cover plate 108. In step S903, the remaining portion of the cover plate is separated from the cured layer. In the embodiments discussed above, the separation of the cover plate 108 and the substrate 102 includes: the step of generating a crack by mechanical force such as pushing or pneumatic pressure; the step of applying vacuum pressure to the outer partition to extend the crack, firmly holding the cover plate 108, moving the cover plate 108 upward and away from the substrate 102 in the Z direction with a force sufficiently safe to avoid unlocking the cover plate upward; and the step of applying a vacuum to the center of the cover plate 108 during the upward movement in the Z direction to complete the separation. Alternatively, or in combination with the above Z-direction movement scheme, the extension of the separation can also be influenced by continuously applying an in-plane (or lateral) directional flow with high pressure from one or more sides of the substrate (not shown).

[0059] In the embodiment shown in Figure 6, the mechanical pin 606 ( Figure 6A ) or fluid nozzle 616 ( Figure 6B Cracks are initiated by applying an upward force through the notch 608 in the wafer. Figure 10 Another embodiment of a substrate chuck configured to induce a separation crack is shown. Here, the substrate chuck 624 includes a separate retractable pin 626 that can induce a separation crack when the cover plate 108 and the substrate are arranged non-concentrically. This non-concentric arrangement causes a portion 628 of the cover plate 108 to overhang over the substrate 102. A crack 602 can be generated by applying a force to the overhanging portion 628 via movement of the pin 626. Alternatively, the overhanging portion 608 can also be obtained by using a cover plate slightly larger than the substrate. In this way, the cover plate 108 can still be arranged concentrically with the substrate 102. In either case, for example in Figure 6A In embodiments 6B or others, the substrate chuck 624 may also include mechanical pins or nozzles spaced apart from the pins 626 to form multiple portions around the periphery of the cover plate for initiating separation cracks.

[0060] Covered chuck

[0061] As described above, the cover plate 108 is preferably held or supported by a cover plate chuck 118, which applies pressure or vacuum (negative pressure) to the volume between the cover plate and the chuck surface within an annular partition 303, defined by groove banks 307 extending from the clamp surface. Except for the outermost groove bank 307a, the inner groove banks 307b preferably have the same height, such that the depth of the gap between adjacent inner groove banks 307b remains constant. For reasons such as minimizing gas filling or evacuation response time, groove bank stiffness characteristics, and limiting thermal effects (e.g., expansion or contraction), the groove bank height (i.e., the depth of the gap) is typically kept very small, for example, on the order of tens to thousands of micrometers. In operation, when a vacuum is applied to the annular partition to hold the cover plate against the groove banks of that partition, a vacuum seal is formed at the cover plate-groove bank interface. However, when sufficient force or pressure is applied to the cover plate in the direction opposite to the clamp vacuum, the substrate can be lifted away from the groove banks of the chuck. At some gap between the cover plate and the groove bank, a failure of the vacuum seal or other leakage can cause the vacuum pressure within that section to drop or even reach zero. The cover plate may then unexpectedly disengage from the chuck. Furthermore, even if the cover plate is not disengaged, for example, as shown in Figure 4 and... Figure 5 Vacuum leaks can also disrupt the required control level when vacuum pressure is released sequentially from adjacent ring sections during the process. (See Figure 4 and...) Figure 5 During this process, such leakage at the outer bank of the trench may also negatively affect the controlled maintenance of the desired outer edge curvature of the cladding. Similarly, in Figures 7 to... Figure 9 During the process, leakage on the outer bank of the trench may disrupt the initiation and propagation of separation cracks.

[0062] To address such unintended leakage, a cover plate chuck 1118 comprising a grooved structure 1109 is provided, such as Figure 11A and 11B As shown in the diagram. Similar to the covered chuck 1118, the covered chuck 1118 also includes a plurality of groove banks 307, which may be defined as a series of inner groove banks 307a and peripheral groove banks 307b protruding from the surface 1119 of the covered chuck 1118. Figure 11B and Figure 12As shown, surface 1119 is a holding or retaining surface for holding or securing the cover plate 108. A series of inner sections 303a are defined by groove banks 307a. A groove 1109 recessed from the surface of the chuck 1118 is formed in at least one annular section 303. The grooves may be concentric and located between corresponding groove banks of the annular sections. The groove 1109a formed in the inner annular section 303a is located at a position away from the center of the chuck 1118 relative to the width of the associated inner annular section. In contrast, the groove 1109b formed in the peripheral annular section 303b is located in a region closer to the center of the cover plate chuck 1118 relative to the width of the outer annular section. That is, the groove 1109a formed in the inner annular section 303a is formed at the outer diameter of the corresponding inner annular section 303a, while the groove 1109b formed in the peripheral annular section 303b is formed at the inner diameter of the peripheral section 303b.

[0063] In operation, trench 1109 acts as a buffer to provide a uniform high vacuum pressure source that continues to act on the cladding even when gaps exist between the cladding plates at the trench banks far from the trench. In this way, the sequential outward radial release of vacuum and the application of positive pressure to the central and adjacent annular sections can be carried out in a controlled manner. That is, even if the magnitude of the positive pressure applied to the adjacent inner sections could deflect the cladding plates sufficiently to create gaps at the distal trench banks, the vacuum pressure applied in a given annular section can be maintained. In other words, providing trench 1109 allows for tolerance of a certain degree of leakage without interrupting the intended process. Similarly, trench 1109b located in the peripheral annular sections with a smaller outer trench bank height operates to maintain sufficient vacuum pressure in the outer annular sections even when small gaps exist at the outer trench banks. This allows the outer periphery of the cladding to maintain the desired curvature for the final diffusion and coalescence of the deposited formable material droplets, even in the presence of a certain degree of leakage (see...). Figure 4D ) and the initiation and propagation of the separation crack (see, for example, Figure 6).

[0064] Figure 12 This is an enlarged cross-sectional view of the exemplary trench structure 1109b. The specific trench dimensions and associated locations within the annular partition required to achieve the desired vacuum buffering performance depend on the height of the cover plate clamp trench bank and the width of the annular partition. Figure 12In the example shown, the groove 1109b is located within the ring partition 303b and is recessed from the chuck surface. In this example, the height h1 of the outer groove bank 307b is less than the height h2 of the inner groove bank 307a. In typical use, the difference in groove bank height can be in the range of about 5 microns to about 50 microns. The ring partition 303b has a width d. The groove 1109bd is positioned such that the distance of the first edge from the groove bank 307b is d1 and the distance of the second edge from the groove bank 307a is d2. The groove 1109b has a depth h3 and a width d3. In this embodiment, the relationships between these parameters satisfy the following conditions:

[0065] h1 < h2

[0066] h3 > 10h2

[0067] d3 < 0.5d

[0068] d1 > d2 + d3.

[0069] A port 305 that connects the groove 1109b to a pressure source (not shown) intersects or otherwise lies within the groove. If the port does not intersect the groove, the necessary high pressure cannot be maintained and the groove will fail. In the above embodiment, the outer groove bank h1 is where leakage is expected to occur. For the inner ring groove 1109b, the groove bank heights can be the same, i.e., h1 = h2. In this case, the distance d1 is measured from the designated groove bank where leakage is expected (i.e., h1 or h2). For example, in Figure 11A and 11B embodiments, the inner ring partition 303a includes a groove 1109a positioned closer to the outer groove bank of its corresponding ring partition (measured radially from the chuck center) to mitigate leakage at the inner groove bank during sequential vacuum release and subsequent pressurization of the ring partitions, as described in the process associated with FIGS. 4 - 5.

[0070] According to this specification, further variations and alternative embodiments of the various aspects will be apparent to those skilled in the art. Therefore, this specification is to be construed as illustrative only. It should be understood that the forms shown and described herein are to be regarded as examples of embodiments. Elements and materials can be substituted for those shown and described herein, components and processes can be reversed, and certain features can be used independently, all of which will be apparent to those skilled in the art after benefiting from this specification.

Claims

1. A method, the method comprising: While maintaining the stack by applying negative pressure to the cover plates using a cover plate chuck, cracks are generated at the edges of the stack by the cured layer sandwiched between the substrate and the cover plates. The crack extends from the portion on the edge of the stack along the outer periphery of the surfaces where the cover plate and the cured layer contact each other; as well as The cover plate is moved relative to the substrate to complete the separation of the cover plate from the substrate. When the stack is viewed from the side, the cover plate has a portion that hangs over the substrate; and The crack is formed between the cured layer and the cover plate, and is generated during the formation process by applying force to the portion of the cover plate.

2. The method according to claim 1, wherein, During the generation process, the crack is generated by introducing a positive fluid pressure at the location on the edge between the substrate and the cover plate to generate the crack.

3. The method according to claim 1, wherein, The method further includes: The cover plate is held in the cover plate chuck by negative fluid pressure; and During the expansion process, a high flow of negative fluid pressure is applied to the peripheral sections of the cover plate to expand the crack along the edge of the stack.

4. The method according to claim 1, wherein, During the movement, the cover plate is moved away from the substrate using a cover plate chuck.

5. The method according to claim 1, wherein, During the movement, a negative fluid pressure is applied to the central section of the cover plate by the cover plate chuck to complete the separation of the cover plate from the substrate.

6. The method according to claim 1, wherein, During the generation process, force is applied by introducing positive fluid pressure or mechanical contact.

7. A leveling system, the leveling system comprising: A cover plate chuck configured to hold a stack of covers plates by applying negative pressure, the stack having a cured layer sandwiched between a substrate and a cover plate; A substrate chuck configured to hold a substrate; as well as A force source, configured to apply force to portions of the stack at the edges of the stack while maintaining the stack by applying negative pressure to the cover plates via the cover plate chuck, thereby creating cracks at the portions of the edges between the cured layer and the cover plates to initiate separation between the cured layer and the cover plates. When the stack is viewed from the side, the cover plate has a portion that hangs over the substrate; and The force source generates the crack by applying force to the portion of the cover plate.

8. The leveling system of claim 7, wherein the cover plate chuck includes a pattern of groove banks, and one of the groove banks located near the edge of the cover plate chuck is recessed below other groove banks located at intervals within the cover plate chuck to allow the cover plate to deflect toward the cover plate chuck while creating the crack.

9. The leveling system according to claim 7, wherein, The leveling system also includes a substrate chuck configured to hold the substrate with negative fluid pressure.

10. The flattening system of claim 9, wherein the substrate chuck includes a pattern of groove banks, and one of the groove banks located at the edge of the substrate chuck is recessed below other groove banks located at the interior of the substrate chuck to allow the substrate to deflect toward the substrate chuck while creating the crack.

11. The leveling system of claim 7, wherein the force source comprises a mechanism for generating lateral mechanical thrust or a positive fluid pressure source toward the edge of the cover plate.

12. The flattening system of claim 7, wherein the substrate includes a notch disposed at its edge, and the force source includes a negative fluid pressure source applied to the cover plate via the notch.

13. The leveling system according to claim 7, wherein, The leveling system also includes a negative fluid pressure source for applying negative fluid pressure to the cover plate via the cover plate chuck.

14. A method of manufacturing an article, the method comprising: A curing layer is formed between the substrate and the cover plate; While maintaining the stack by applying negative pressure to the cover plates using the cover plate chuck, cracks are generated at the edges of the stack by the cured layer sandwiched between the substrate and the cover plates. The crack extends from the portion on the edge of the stack along the outer periphery of the surfaces where the cover plate and the cured layer contact each other; as well as Separate the cover plate from the cured layer. When the stack is viewed from the side, the cover plate has a portion that hangs over the substrate; and The crack is formed between the cured layer and the cover plate, and is generated during the formation process by applying force to the portion of the cover plate.

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