Improved heat transfer coefficient (HTC) between the web and the "rotor-stator type" drum in a roll-to-roll (R2R) PVD coating system.

Abstract

A gas cushion drum for improved heat extraction is provided. In one embodiment, the gas cushion drum may include a curved cooling drum having a cooling drum surface extending between two opposing circular bases; a pair of rotating disks coupled to the circular bases of the curved cooling drum; a pair of nozzle outlets positioned along the cooling drum surface and configured to release gas across the cooling drum surface; and a substrate coupled to the circumferential surfaces of each of the pair of rotating disks and positioned above the pair of nozzles, wherein a substantially uniform gas cushion is formed between the inner surface of the substrate and the cooling drum surface from the gas released from the pair of nozzle outlets.

Description

Technical Field

[0001] The implementations described herein generally relate to metal electrodes, more specifically lithium-containing anodes, high-performance electrochemical devices such as primary electrochemical devices and secondary electrochemical devices (including the aforementioned lithium-containing electrodes), and methods of manufacturing the same.

Background Art

[0002] Lithium (Li) ion batteries have played a critical role in the development of current-generation mobile devices, microelectronics, and electric vehicles. A typical lithium-ion battery consists of a positive electrode (cathode), a negative electrode (anode), an ion-conductive electrolyte, a porous separation membrane (electrical insulator) positioned between the two electrodes to physically separate the electrodes, and a package.

[0003] Processes for depositing lithium on substrates (e.g., large flexible substrates) can be temperature-sensitive and may lead to the formation of wrinkles and other defects. The substrate may be guided and supported by coating equipment having a surface. While the substrate moves over the curved drum surface of a rotating drum such that it passes one or more evaporation sources, vapor may be deposited onto the substrate. A drum may be used to maintain and control the temperature of the substrate, which may be achieved by cooling and pressurizing the back side of the substrate to maintain a gas cushion between the substrate and the curved drum surface, and optimizing heat transfer for cooling. The gas cushion can be calibrated to mitigate the effects of latent heat that cause film stress, or the effects of misalignment that cause machine-direction wrinkles.

[0004] Accordingly, there is a need for apparatus and methods for maintaining a gas cushion to enhance substrate cooling and improve throughput.

Summary of the Invention

[0005]

[0005] In some embodiments, a gas cushion drum for improved heat extraction is provided. The gas cushion drum includes a curved cooling drum having a cooling drum surface extending between two opposing circular bases, and a pair of rotating disks coupled to the circular bases of the curved cooling drum. The pair of rotating disks are coaxial with the longitudinal axis of the curved cooling drum, which extends substantially parallel to the cooling drum surface and through the centers of each of the circular bases. The gas cushion drum also includes a pair of nozzle outlets substantially arranged along the cooling drum surface and configured to release gas across the cooling drum surface, and a substrate coupled to the circumferential surface of each of the pair of rotating disks and positioned above the pair of nozzles. The inner surface of the substrate and the cooling drum surface form a substantially uniform gas cushion with the gas released from the pair of nozzle outlets.

[0006] In another embodiment, a gas cushion drum for improved heat extraction is provided. The gas cushion drum includes a curved drum body having a pair of circular bases and a cooling drum surface extending between them. The gas cushion drum also includes a center rod extending through the centers of each of the pair of circular bases and a pair of rotating disks coupled to both ends of the center rod. The centers of each of the pair of rotating disks are coaxial with the center rod and the cooling drum surface. The gas cushion drum further includes a pair of nozzle outlets arranged along the cooling drum surface and configured to release gas across the cooling drum surface, a substrate coupled to the circumferential surface of each of the pair of rotating disks and positioned above the pair of nozzles, and a gap between the substrate and the cooling drum surface. When gas is released from the pair of nozzle outlets, a substantially uniform gas cushion is formed.

[0007] In some embodiments, a method is provided for forming a gas cushion above a gas cushion drum for improved heat extraction. This method includes coupling a pair of rotating disks to both ends of a center rod extending through the center of a circular base of a curved drum body, discharging gas across the cooling drum surface through a pair of nozzle outlets positioned along the cooling drum surface, and forming a substantially uniform gas cushion in the gap between the inner surface of a substrate and the cooling drum surface. The pair of rotating disks and the cooling drum surface extending between the circular bases are coaxial with the center rod. The substrate is coupled to both circumferential surfaces of the pair of rotating disks and positioned above a pair of nozzles.

[0008] To enable a detailed understanding of the features of this disclosure described above, a more detailed description of this disclosure, briefly summarized earlier, can be obtained by referring to embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate exemplary embodiments and should not be considered to limit the scope of this disclosure, as other equally valid embodiments are also acceptable. [Brief explanation of the drawing]

[0009] [Figure 1] An exemplary coaxial cross-section of a gas cushion cooling drum according to several embodiments described herein is shown. [Figure 2] A shows an exemplary overhead view of a gas cushion cooling drum according to some embodiments described herein. B shows an exemplary overhead view of a gas cushion cooling drum according to some embodiments described herein. [Figure 3] A and B show exemplary cross-sections of a gas cushion cooling drum according to some embodiments described herein. [Figure 4] An exemplary coaxial cross-section of a gas cushion cooling drum according to several embodiments described herein is shown. [Figure 5]An illustrative overhead view is shown of a set of gas cushion cooling drum nozzles according to some embodiments described herein. [Figure 6] A shows an exemplary overhead view of a set of gas cushion cooling drum nozzles according to some embodiments described herein. B shows an exemplary bottom view of a set of gas cushion cooling drum nozzles. [Figure 7] A shows an exemplary overhead view of a set of gas cushion cooling drum nozzles according to some embodiments described herein. B shows an exemplary bottom view of a set of gas cushion cooling drum nozzles according to some embodiments described herein. [Figure 8] An illustrative overview of a configuration for a set of gas cushion cooling drum nozzle outlets according to several embodiments described herein is shown. [Figure 9] An illustrative overview of a configuration for a set of gas cushion cooling drum nozzle outlets according to several embodiments described herein is shown. [Figure 10] An illustrative overview of a configuration for a set of gas cushion cooling drum nozzle outlets according to several embodiments described herein is shown. [Figure 11] An illustrative overview of a configuration for a set of gas cushion cooling drum nozzle outlets according to several embodiments described herein is shown. [Figure 12] An illustrative overview of a configuration for a set of gas cushion cooling drum nozzle outlets according to several embodiments described herein is shown. [Figure 13] This is a flowchart illustrating a method for coating a substrate according to some embodiments described herein.

[0010] To facilitate understanding, the same reference numerals were used whenever possible to indicate identical elements common to the drawings. It was considered that elements and features of one embodiment can be usefully incorporated into other embodiments without further mention. [Modes for carrying out the invention]

[0011] A vapor deposition system for coating a web substrate guided on a rotatable coating drum is referred to herein as a roll-to-roll (R2R) deposition system. As described herein, flexible substrates can be considered to include, among other things, films, foils, webs, strips of plastic material, metals, paper, or other materials. Typically, terms such as “web,” “foil,” “strip,” and “substrate” are used synonymously.

[0012] Energy storage devices, such as lithium-ion batteries, typically include a positive electrode (e.g., cathode) and a negative electrode (e.g., anode), which are separated by a polymer separator containing a liquid electrolyte. Solid-state batteries also typically include a positive electrode and a negative electrode, but both the polymer separator and the liquid electrolyte are replaced with ion-conducting materials. Lithium can be deposited on a substrate by evaporating molten lithium or lithium vapor onto the substrate (e.g., graphite-coated copper foil, copper foil, or other suitable material).

[0013] In an R2R system, lithium is deposited on the substrate as it moves between a roll unwinding system and a roll winding system. As the substrate moves between the two systems, it passes through a deposition evaporator while remaining coupled to a gas cushion drum. The deposition evaporator deposits lithium on the substrate, and the gas cushion drum cools the deposited lithium. In some cases, the substrate passes through the deposition evaporator just before passing through the gas cushion drum. While lithium is being deposited, it condenses on the substrate, releasing latent heat, which can make the substrate susceptible to damage from thermal loads. To mitigate the effects of heat, the substrate temperature is kept below a certain temperature. In one example, the gas cushion drum can mitigate the effects of latent heat. As lithium is deposited on the outer surface of the substrate, the inner surface of the substrate is positioned above the gas cushion, which holds the substrate above the gas cushion drum. The gas cushion also cools the underside of the substrate by exhausting a gas with a high heat transfer coefficient between the gas cushion drum and the substrate. The lithium deposition rate on the substrate is limited by the substrate cooling rate. In many cases, the gas cushion contains a cooling gas that does not react with lithium. In some embodiments, the cooling gas includes argon, helium, or a combination thereof. In some embodiments, the target substrate cooling temperature is between 50°C and 90°C (e.g., 80°C), but other values ​​are also considered.

[0014]

[0025] In some implementations, the R2R system maintains a uniform gap distance between the substrate and the drum surface. Conventional solutions to mitigate damage to the substrate include mechanical solutions, such as placing retaining rollers around the cooling drum to physically bond the substrate to the drum in order to prevent expansion or melting of the substrate. These solutions can lead to edge damage and delamination. The embodiments described herein provide a constant gas cushion that maintains a uniform gap between the substrate and the drum surface, thereby reducing damage to the substrate as it moves across the gas cushion drum.

[0015] In addition, the effects of latent heat can be mitigated by optimizing gas conduction. Heat conduction (conductance) between the substrate and the drum can be a combination of contact, radiation, and gas conductance. Of these three modes, gas conductance is the most dominant. Embodiments provided herein ensure that a constant gap is maintained between the substrate and the drum, which is achieved in part by providing nozzle openings strategically placed to ensure uniform gas pressure, and by having a cooling drum with rotor and stator segments.

[0016] FIG. 1 shows a schematic cross-sectional view of one implementation of a cooling drum apparatus 100 incorporating a gas cushion 110. The gas cushion 110 is formed in accordance with the implementations described herein. The apparatus 100 includes a drum body core 102 disposed around a center rod 116, the drum body core 102 extending radially outward from the rod 116. A cooling internal circuit 104 extends radially outward from the surface 118 of the drum body core 102, and a stainless steel (SST) / copper shell 106 extends radially outward from the surface 120 of the cooling internal circuit 104. A set of gas supply nozzles 108 is disposed on the surface 118 of the drum body core 102 and extends in a planetary configuration relative to the surface 122 of the SST / copper shell 106. The inlets 124 of the gas supply nozzles 108 are substantially disposed on the surface 118 of the drum body core 102. The outlets 126 of the gas supply nozzles 108 are substantially disposed on the surface 122 of the SST / copper shell 106. The gas supply nozzles 108 may supply argon gas, helium gas, or other suitable gases. Gas from the gas supply nozzles 108 travels from the drum body core 102 through the inlets 124 and the outlets 126 to the surface 122 of the SST / copper shell 106, generating the gas cushion 110. The gas cushion 110 extends radially outward from the surface 122 of the SST / copper shell 106 and is truncated at the inner surface 128 of the substrate 112. The gas cushion 110 may be composed of argon gas, helium gas, or any other suitable gas. The substrate 112 moves in the machine direction over the apparatus 100 while maintaining a constant gas cushion 110 in response to dynamic web tension 114. The substrate 112 is not in contact with the surface 122 of the SST / copper shell 106.

[0017] In one embodiment, the apparatus 100 is effective for reducing the thermal resistance between the substrate 112 and the gas cushion drum surface (e.g., the surface 122 of the SST / copper shell 106). The constant gas cushion 110 between the substrate 112 and the surface 122 provides dominant gas conduction and low thermal resistance, facilitating effective cooling of the substrate 112.

[0018] FIGS. 2A and 2B show exemplary overhead views of a gas cushion cooling drum apparatus 200 incorporating the gas cushion 110 of FIG. 1 in accordance with certain embodiments. The apparatus 200 includes at least one pair of rotating disks 202 arranged coaxially on each circular end 210 of a cylindrical static drum body 208. The cooling line 204 extends from the first rotating disk 202a of the pair of rotating disks 202 to the second rotating disk 202b of the pair of rotating disks 202. The portions of the cooling line 204 extending between the pair of rotating disks 202 are substantially parallel to each other. The portions of the cooling line 204 extending along the respective inner surfaces 212 of the pair of rotating disks 202 are coupled to a set of cooling line joints 214 and extend from the set of cooling line joints 214. In some embodiments, the joints 214 supply a coolant (not shown) to the cooling line 204. The coolant may be any material suitable for cooling. In some embodiments, the cooling line 204 is disposed inside the static drum body 208. In some embodiments, the cooling line 204 is disposed outside the static drum body 208. In some embodiments, the cooling line 204 is disposed within the apparatus 200 to optimize the heat transfer coefficient.

[0019]

[0030] The substrate 206 is disposed on the respective peripheral surface 216 of the rotating disks 202, and stretches between the rotating disks 202 without contacting the surface 218 of the static drum body 208. The pair of rotating disks 202 rotate about an axis 220 to move the substrate 206 across the apparatus 200. The static drum body 208 and the cooling line 204 remain stationary as the rotating disks 202 rotate. In some embodiments, the substrate 206 moves via frictional contact along the machine direction 222. The apparatus 200 can also simplify the mounting of a sensor array for monitoring, such as monitoring of gas cushion pressure, gas cushion flow rate, and gas cushion drum surface temperature.

[0020] In some embodiments, the apparatus 200 has a stator drum body 208 and a rotating disk 202, where the stator drum body 208 can be cooled by a cooling line 204. The surface 218 of the stator drum body 208 is useful for heat exchange with the inner surface (not shown) of the substrate 206 via gas conduction. If the cooling line 204 running parallel to the apparatus 200 is positioned close to the surface 218, the surface 218 can be cooled uniformly.

[0021] Figure 3A shows an example of a lateral cross-section of a gas cushion cooling drum device 300 according to a particular embodiment. Figure 3B shows a partially enlarged view of the device 300 in Figure 3A. The device 300 in Figures 3A and 3B can be understood by referring to the device 200 in Figure 2. The device 300 includes at least a rotating disk 202, a stator drum body 208, a substrate 206, and a gas cushion 302. The gas cushion 302 is formed in a gap 306 surrounded by the rotating disk 202, the stator drum body 208, and the substrate 206. The gas cushion 302 is demarcated by the coaxial surface 212 of the rotating disk 202, the surface 304 of the stator drum body 208, and the inner surface 308 of the substrate 206. In some embodiments, the gas cushion 302 may be defined according to the gap 306. The gap 302 may be a radial measurement from the surface 304 of the stator drum body 208 to the inner surface 308 of the substrate 206. This gap 306 can be defined by the difference in radius between the rotating disk 202 and the stator drum body 208. In some embodiments, the gap 302 can be between about 40 micrometers and about 210 micrometers (e.g., 50 micrometers to 200 micrometers), but other values ​​are also considered. The device 300 also allows for the easy attachment of sensors for monitoring, such as gas cushion pressure, gas cushion flow rate, and gas cushion drum surface temperature.

[0022] In some cases, the gap 306 may extend between the stator drum body 208 and the inner surface 308, the length of which is approximately 0.1 mm to approximately 1.5 mm (e.g., 0.5 mm to 1 mm), although other values ​​may also be considered. This length allows for clearance between the rotating disk 202 and the stator drum body 208. In some cases, a gas cushion (not shown) within the gap 302 may leak into the vacuum system due to the coaxial gap 302.

[0023] Figure 4 shows an example of a coaxial cross-section of the gas cushion cooling drum apparatus 400, which can be understood by referring to apparatuses 200 and 300. Apparatus 400 includes at least a rotating disk 202, a stator drum body 208, a cooling line 204, and a cooling line junction 214. With the implementation of apparatus 400, gas cushion coverage is limited to the deposition zone, lower temperatures are achieved while reducing the coolant usage rate. Apparatus 400 also facilitates the mounting of sensors for monitoring, such as monitoring of gas cushion pressure, gas cushion flow rate, and gas cushion drum surface temperature.

[0024]

[0035] Figures 5, 6A, and 6B show an exemplary gas cushion cooling drum nozzle device 500, which can be understood by referring to devices 200, 300, and 400. Device 500 includes at least a nozzle plenum 502 having a pair of nozzle inlets 602, a pair of nozzle outlets 604, and a gas cushion drum surface 304. The nozzle plenum 502 may be substantially located within the stator drum body 208. The nozzle inlets 602 are located on the upper surface 606 of the nozzle plenum 502. In some embodiments, the nozzle inlets 602 supply gas to the nozzle plenum 502 for distribution to the gas cushion 302, as described above. In some embodiments, the gas may be argon, helium, or any other suitable gas. The nozzle outlets 604 are located on the lower surface 608 of the nozzle plenum 502. In some embodiments, nozzle outlets 604 are located along both lateral ends 610 of the nozzle plenum 502 and extend from the nozzle plenum 502 to the gas cushion drum surface 304 (see Figure 7A). In some embodiments, there may be approximately 15 to 25 nozzle outlets 604 (e.g., 19 nozzle outlets 604) along each of the lateral ends 610 of the nozzle plenum 502, but other values ​​are also considered. The gas cushion drum surface 304 is substantially coupled to the nozzle outlets 604. In some embodiments, gas is discharged from the nozzle outlets 604 through corresponding openings in the gas cushion drum surface 304 to maintain a constant gas cushion 310 as described above.

[0025] Figures 7A and 7B show an exemplary arrangement of the apparatus 500 within the stator drum body 208. In some embodiments, the gas cushion drum surface 304 includes an array of nozzle outlets, for example, an array of nozzle outlets 604. The array of nozzle outlets 604 supplies gas to the gap 306 between the substrate 206 and the gas cushion drum, generating a gas cushion 302. The gas cushion 302 is formed between the substrate and the drum as the substrate 206 moves in the mechanical direction 702. In some embodiments, the apparatus 500 provides a separate gas supply (not shown) to each combination of nozzle outlets 604. Since the curvature of the substrate is a function of tension and gap pressure, the separate gas supply assigned to each nozzle outlet 604 can promote a uniform gas pressure profile in the gap 306 between the substrate 206 and the gas cushion drum surface 304.

[0026] Figures 8 to 12 show exemplary overhead views of various embodiments 800, 900, 1000, 1100, and 1200 of a set of gas cushion drum nozzle outlets (for example, on drums 200 / 300 / 400) along the gas cushion drum surface 304 (which facilitates precise and uniform pressure control). In the exemplary nozzle outlet array 800 in Figure 8, a set of active nozzles 802 are arranged across eight horizontal rows 804. Of the eight horizontal rows 804, the first four horizontal rows 806 are equidistant from each other and extend laterally across the gas cushion drum surface 304. Of the eight horizontal rows 804, the second four horizontal rows 808 are symmetrical with respect to the first four horizontal rows 806 with respect to the horizontal axis 810. The nozzle outlets 802 in each row are equidistant from each other. In some embodiments, the outlet is about 0.2 mm to about 6 mm (e.g., 0.5 mm to 5 mm), but other values ​​are also considered. In some cases, embodiments 800, 900, 1000, 1100, and 1200 can be arranged on the surface 304.

[0027] In the exemplary nozzle outlet array 900 shown in Figure 9, a pair of active nozzle rows 912 and a pair of inactive nozzle rows 902 are arranged across eight horizontal rows 904. The first four horizontal rows 906 of the eight horizontal rows 904 are equidistant from each other and extend laterally across the gas cushion drum surface 304. The second four horizontal rows 908 of the eight horizontal rows 904 are symmetrical with respect to the first four horizontal rows 906 with respect to the horizontal axis 910. The pair of active nozzles 912 includes the two symmetrical rows closest to the horizontal axis. The pair of inactive nozzles 902 includes nozzles not included in the pair of active nozzles 912. The nozzle outlets 902 / 912 of each row 904 are equidistant from each other. In some embodiments, the outlet 902 / 912 is approximately 0.2 mm to approximately 6 mm (e.g., 0.5 mm to 5 mm), but other values ​​are also considered.

[0028] In the exemplary nozzle outlet array 1000 shown in Figure 10, a pair of active nozzle rows 1012 and a pair of inactive nozzle rows 1002 are arranged across eight horizontal rows 1004. The first four horizontal rows 1006 of the eight horizontal rows 1004 are equidistant from each other and extend laterally across the gas cushion drum surface 304. The second four horizontal rows 1008 of the eight horizontal rows 1004 are symmetrical with respect to the first four horizontal rows 1006 with respect to the horizontal axis 1010. The pair of active nozzles 1012 includes two symmetrical rows that are second closest to the horizontal axis. The pair of inactive nozzles 1002 includes nozzles not included in the pair of active nozzles 1012. The nozzle outlets 1002 / 1012 in each row 1004 are equidistant from each other. In some embodiments, the outlet 1002 / 1012 is approximately 0.2 mm to approximately 6 mm (e.g., 0.5 mm to 5 mm), but other values ​​are also considered.

[0029]

[0040] In the exemplary nozzle outlet array 1100 shown in Figure 11, a pair of active nozzle rows 1112 and a pair of inactive nozzle rows 1102 are arranged across eight horizontal rows 1104. The first four horizontal rows 1106 of the eight horizontal rows 1104 are equidistant from each other and extend laterally across the gas cushion drum surface 304. The second four horizontal rows 1108 of the eight horizontal rows 1104 are symmetrical with respect to the first four horizontal rows 1106 with respect to the horizontal axis 1110. The pair of active nozzles 1112 includes two symmetrical rows second furthest from the horizontal axis 1110. The pair of inactive nozzles 1102 includes nozzles not included in the pair of active nozzles 1112. The nozzle outlets 1102 / 1112 in each row 1104 are equidistant from each other. In some embodiments, the outlet 1102 / 1112 is approximately 0.2 mm to approximately 6 mm (e.g., 0.5 mm to 5 mm), but other values ​​are also considered.

[0030] The exemplary nozzle outlet array 1200 in Figure 12 is configured with a pair of active nozzle rows 1212 and a pair of inactive nozzle rows 1202 arranged across eight horizontal rows 1204. Of the eight horizontal rows 1204, the first four horizontal rows 1206 are equidistant from each other and extend laterally across the gas cushion drum surface 304. Of the eight horizontal rows 1204, the second four horizontal rows 1208 are symmetrical with respect to the first four horizontal rows 1206 with respect to the horizontal axis 1210. The pair of active nozzles 1212 includes the two symmetrical rows furthest from the horizontal axis 1210. The pair of inactive nozzles 1202 includes nozzles not included in the pair of active nozzles 1212. The nozzle outlets 1202 / 1212 in each row 1204 are equidistant from each other. In some embodiments, the outlet 1202 / 1212 is approximately 0.2 mm to approximately 6 mm (e.g., 0.5 mm to 5 mm), but other values ​​are also considered.

[0031] Figure 13 is a flowchart illustrating a method 1300 for passivating a material placed on a substrate, according to an embodiment described herein.

[0032] In operation 1302, a pair of rotating disks are coupled to both ends of a center rod extending through the curved drum body of the gas cushion drum. The pair of rotating disks are coaxial with the center rod. The curved drum body includes a cooling drum surface extending between the opposing circular bases of the curved drum body. In some embodiments, the pair of rotating disks have a first radius greater than a second radius of the curved drum body. In some embodiments, the difference between the first radius and the second radius is between 0.5 millimeters and 5 millimeters.

[0033] In operation 1304, the gas cushion drum releases gas across the cooling drum surface through a pair of nozzle outlets positioned along the cooling drum surface. In some embodiments, the pair of nozzle outlets is coupled to a nozzle plenum in a curved drum body, which is coupled to a pair of gas inlets. In some embodiments, the pair of nozzle outlets includes a pair of active nozzles. In some embodiments, the pair of active nozzles can control a substantially uniform gas cushion. In some embodiments, the pair of nozzle outlets comprises a pair of active nozzles and a pair of inactive nozzles. In some embodiments, the pair of active nozzles and the pair of inactive nozzles can control a substantially uniform gas cushion. In some embodiments, the gas includes argon, helium, or some other gaseous substance.

[0034]

[0045] In operation 1306, the cooling drum forms a substantially uniform gas cushion between the inner surface of the substrate and the surface of the cooling drum. The substrate is coupled to the circumferential surface or end of each of a pair of rotating disks. The substrate is positioned above a pair of nozzles and does not come into contact with the curved drum body.

[0035] By implementing any embodiment described herein, the heat transfer coefficient (HTC) from the surface of the stator drum body to the substrate can be significantly improved, and the lithium deposition rate can be optimized. In particular, the HTC from the surface of the stator drum body to the substrate is approximately 500 watts / square meter (W / m²) per Kelvin. 2 From above / K, approximately 1200W / m 2 / K or less (for example, approximately 800W / m) 2 It can be between / K), but other values ​​are also considered.

[0036] While this specification includes many specific implementation details, these should not be considered limitations on the scope of claims, but rather should be interpreted as descriptions of features that may be specific to a particular implementation. In the context of separate implementations, certain features described herein can be implemented in combination or in a single implementation. Conversely, various features described in the context of a single implementation can be implemented in multiple implementations, separately or in any suitable subcombination. Furthermore, the aforementioned features may be described as acting in a particular combination, and may even be claimed as such from the outset, but in some cases one or more features from a claimed combination may be excluded from the combination, and the claimed combination may be directed to a subcombination or a variation of a subcombination.

[0037] A specific implementation of the subject is described. It will be apparent to those skilled in the art that other implementations, modifications, and substitutions of the described implementation are within the scope of subsequent claims. Although operations are depicted in a specific order in the drawings or claims, this should not be understood as meaning that such operations must be performed in a specific order or sequence, or that all illustrated operations must be performed to achieve the desired result (some operations may be optional). In certain circumstances, multitasking or parallel processing (or a combination of multitasking and parallel processing) may be advantageous and may be performed as needed.

[0038] Furthermore, the separation or integration of various system modules and components in the aforementioned implementations should not be understood as requiring such separation or integration in all implementations. It should be understood that the described program components and systems are generally integrable into one software product or packaged into multiple software products.

[0039]

[0050] Therefore, the exemplary implementations described above do not define or limit this disclosure. Other modifications, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure.

[0040] While various steps in the embodiment of the method or process are presented and described sequentially, those skilled in the art will appreciate that some or all of the steps can be performed in different orders, combined, or omitted, and that some or all of the steps can be performed in parallel. The steps can be performed actively or passively. The method or process can be repeated or extended to support multiple components or multiple users in a field environment. Therefore, the claims should not be considered to be limited to a specific arrangement of steps shown in the flowchart or diagram.

[0041] Unless otherwise specified, all technical and scientific terms used shall have the same meaning as those generally understood by those skilled in the art to which these systems, apparatus, methods, processes, and compositions belong.

[0042] In this disclosure, terms such as top, bottom, side, above, below, up, down, upward, downward, horizontal, and vertical do not refer to absolute directions. Rather, these terms refer to directions relative to an unspecified reference plane, which may be vertical, horizontal, or other angular directions.

[0043] "A," "an," and "the" include plural references unless the context explicitly indicates otherwise. In the claims, a singular reference to an element is intended to mean "one or more" rather than "one and just one" unless otherwise stated. Unless otherwise stated, the term "several" refers to one or more terms.

[0044]

[0055] Embodiments of this disclosure may appropriately “comprise,” “consist,” or “consist essentially of” the disclosed limit features, and may be performed even if the limit features are not disclosed. The words “comprise,” “has,” and “include,” as used herein and in the appended claims, and their grammatical variations, are all intended to have an open and non-restrictive meaning, respectively, that does not exclude additional elements or steps.

[0045] "Optional" and "optionally" may mean whether the following material, event, or situation exists or occurs, or does not exist or occur. The specification includes examples in which the material, event, or situation occurs, or in which none of these occur.

[0046] As used here, the term “determining” encompasses a variety of actions. “Determining” may include, for example, calculation, computation, processing, derivation, investigation, retrieval (e.g., searching tables, databases, or other data structures), and confirmation. “Determining” may also include, for example, receiving information, and for example, accessing data in memory. “Determining” may also include resolving, choosing, selecting, and establishing.

[0047] When the words "approximately" or "about" are used, the term may mean that the value may vary by up to ±10%, up to 5%, up to 2%, up to 1%, up to 0.5%, up to 0.1%, or up to 0.01%.

[0048] A range can be expressed as the range from one specific value to another (including the endpoints).

[0049]

[0060] As used, terms such as “First” and “Second” are arbitrarily assigned and used solely to distinguish two or more components of a system, device, or composition. It should be understood that the terms “First” and “Second” serve no other purpose, are not part of a name or description of a component, and do not necessarily specify the relative location or position of a component. Furthermore, the mere use of the terms “First” and “Second” does not require the existence of a “Third” component, although its possibility should be considered within the scope of the various embodiments described.

[0050] While the embodiments described in detail are limited to a few, those skilled in the art will immediately recognize that many variations are possible in the exemplary embodiments without substantially departing from the scope disclosed above. Therefore, all such variations are intended to be included within the scope of this disclosure, as set forth in the following claims. In the claims, the means-plus-function claims are intended to cover structures that perform the function mentioned, covering not only structural equivalents but also equivalent structures. For example, nails and screws may not be structurally equivalent when nails are used on a cylindrical surface to fasten wooden members together, whereas nails and screws may be equivalent structures when screws are used on a helical surface in an environment for fastening wooden members. It is the express intention of the applicant that no limitation is invoked on the claims under 35 U.S.C. § 112(f), except when the claims explicitly use the words “means for” with the function in question.

[0051] The following claims are intended to encompass the entire scope consistent with the language of the claims, rather than being limited to the embodiments provided.

Claims

1. A gas cushion drum for improved heat extraction, wherein the gas cushion drum comprises at least: A curved cooling drum having a cooling drum surface extending between opposing circular bases, A pair of rotating disks coupled to the circular base of the curved cooling drum, and coaxial with the longitudinal axis of the curved cooling drum, wherein the longitudinal axis of the curved cooling drum extends substantially parallel to the surface of the cooling drum and through the center of the circular base, A set of nozzle outlets arranged substantially along the surface of the cooling drum and configured to discharge gas across the surface of the cooling drum, A substrate is coupled to the circumferential surface of each of the pair of rotating disks and positioned above the set of nozzles. A gas cushion drum comprising a substantially uniform gas cushion formed between the inner surface of the substrate and the cooling drum surface by the gas discharged from the pair of nozzle outlets.

2. The gas cushion drum according to claim 1, wherein the pair of rotating disks have a first radius that is larger than the second radius of the curved cooling drum.

3. The gas cushion drum according to claim 2, wherein the difference between the first radius and the second radius is between 0.5 millimeters and 5 millimeters.

4. The gas cushion drum according to claim 1, wherein the pair of nozzle outlets is connected to a nozzle plenum in the curved cooling drum, and the nozzle plenum is connected to a pair of gas inlets.

5. The gas cushion drum according to claim 4, wherein the set of nozzle outlets comprises a set of active nozzles capable of controlling a substantially uniform gas cushion.

6. The gas cushion drum according to claim 4, wherein the set of nozzle outlets comprises a set of active nozzles and a set of inactive nozzles, and both sets of nozzles are capable of controlling a substantially uniform gas cushion.

7. The gas cushion drum according to claim 1, wherein the gas comprises argon, helium, or some other gaseous substance.

8. The heat transfer coefficient between the cooling drum surface and the substrate is 750 W / m ２ / K and 850W / m ２ A gas cushion drum according to claim 1, located between / K.

9. A gas cushion drum for improved heat extraction, wherein the gas cushion drum is A curved drum body comprising a pair of circular bases and a cooling drum surface extending between the pair of circular bases, A center rod extending through the center of each of the pair of circular bases, A pair of rotating disks coupled to both ends of the center rod, wherein the center of each of the pair of rotating disks is coaxial with the center rod and the surface of the cooling drum, A set of nozzle outlets arranged along the surface of the cooling drum and configured to discharge gas across the surface of the cooling drum, A substrate is coupled to the circumferential surface of each of the pair of rotating disks and positioned above the set of nozzles, and The gap between the substrate and the cooling drum surface, A gas cushion drum comprising a gas outlet, wherein a substantially uniform gas cushion is formed when the gas exits from the pair of nozzle outlets.

10. The gas cushion drum according to claim 9, wherein the pair of rotating disks have a first radius that is larger than the second radius of the curved cooling drum body.

11. A method for forming a gas cushion above a gas cushion drum for improved heat extraction, the method comprising at least A pair of rotating discs are attached to both ends of a center rod that extends through the curved drum body of the gas cushion drum, wherein the curved drum body has a cooling drum surface extending between opposing circular bases, and the pair of rotating discs and the cooling drum surface are coaxial with the center rod. To discharge gas across the surface of the cooling drum through a set of nozzle outlets arranged along the surface of the cooling drum, and A substantially uniform gas cushion is formed in the gap between the inner surface of the substrate and the surface of the cooling drum, wherein the substrate is bonded to the circumferential surfaces of the pair of rotating disks and is positioned above the pair of nozzles. Methods that include...

12. The method according to claim 11, wherein the pair of rotating disks have a first radius that is greater than the second radius of the curved cooling drum.

13. The method according to claim 12, wherein the difference between the first radius and the second radius is between 0.5 millimeters and 5 millimeters.

14. The method according to claim 11, wherein the pair of nozzle outlets is connected to a nozzle plenum in the curved cooling drum, and the nozzle plenum is connected to a pair of gas inlets.

15. The method according to claim 14, wherein the set of nozzle outlets comprises a set of active nozzles capable of controlling a substantially uniform gas cushion.

16. The method according to claim 14, wherein the set of nozzle outlets comprises a set of active nozzles and a set of inactive nozzles, and the set of active nozzles and the set of inactive nozzles are capable of controlling a substantially uniform gas cushion.

17. The method according to claim 11, further comprising coupling the substrate to the respective circumferential surfaces of the pair of rotating disks before the pair of nozzle outlets discharge the gas across the cooling drum surface.

18. The method according to claim 11, further comprising rotating the pair of rotating disks to transport the substrate across the substantially uniform gas cushion without contacting the cooling drum surface.

19. The method according to claim 11, wherein the gas comprises argon, helium, or some other gaseous substance.

20. The heat transfer coefficient between the cooling drum surface and the substrate is 750 W / m ２ / K and 850W / m ２ The method according to claim 11, relating to / K.

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