Lithium metal surface modification using carbonate passivation

Abstract

An exemplary processing method may include transferring a lithium film under a first showerhead. The method may include introducing an oxidizer gas onto the lithium film through the first showerhead. The method may include forming an oxide monolayer on the lithium film. The oxide monolayer may be or may include an oxidizer gas adsorbed on the lithium film. The method may include transferring the lithium film under a second showerhead after the oxide monolayer is formed. The method may include introducing a carbon source gas onto the lithium film through the second showerhead. The method may also include converting the oxide monolayer to a carbonate passivation layer by reaction of the oxide monolayer with the carbon source gas.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS]

[0001] This application claims the benefit of and priority to U.S. Provisional Application No. 63 / 121,013, filed December 3, 2020, which is incorporated herein by reference in its entirety for all purposes.

[0002]

[0002] The present technology relates to thin film deposition processes and chamber components. More particularly, the present technology relates to modified components and deposition methods. [Background technology]

[0003]

[0003] Thin-layer batteries can be manufactured by processes that deposit thin layers of material on the surface of a substrate. Depositing thin layers of material on a substrate requires methods for controlled deposition on large-area substrates. As device sizes continue to shrink, multilayer batteries incorporate increasingly thin metal layers that are prone to oxidation during battery fabrication and susceptible to degradation during operation, such as through dendrite formation. To protect against such degradation, a passivation layer can be deposited on the thin material layer as part of the deposition process. During the deposition of the passivation layer, precursor gases can contaminate the processing chamber, which can affect device quality.

[0004]

[0004] Thus, there is a need for improved systems and methods that can be used to manufacture high quality devices and structures. These and other needs are addressed by the present technology. Summary of the Invention

[0005] An exemplary processing method may include transferring a lithium film under a first showerhead. The method may include introducing an oxidizer gas onto the lithium film through the first showerhead. The method may include forming an oxide monolayer on the lithium film. The oxide monolayer may be or may include the oxidizer gas adsorbed on the lithium film. The method may include transferring the lithium film under a second showerhead after the oxide monolayer is formed. The method may include introducing a carbon source gas onto the lithium film through the second showerhead. The method may also include converting the oxide monolayer to a carbonate passivation layer by reaction of the oxide monolayer with the carbon source gas.

[0006] In some embodiments, the lithium film can be supported on a conductive substrate held in tension between two tension elements of a film deposition system. The processing method can further include depositing lithium on the conductive substrate and planarizing the deposited lithium. The first showerhead can include a first plurality of showerhead units oriented along a first axis. The second showerhead can include a second plurality of showerhead units oriented parallel to the first axis and offset a first distance from the first showerhead. The processing method can further include transporting the lithium film below the first showerhead by movement perpendicular to the first axis. The first showerhead and the second showerhead can each include a plurality of inlets and a plurality of outlets in an arrangement. The plurality of outlets can be positioned to remove excess gas from a region between the plurality of outlets and the lithium film. The orientation of the plurality of outlets can define a flow pattern that restricts excess gas flow parallel to the lithium film outside the region. The processing method can further include forming a pattern on the surface of the lithium film. The pattern can define a plurality of recesses in the surface of the lithium film. The processing method can further include forming a pattern in the carbonate passivation layer, the pattern defining a plurality of recesses in the carbonate passivation layer, the plurality of recesses exposing the surface of the lithium film.

[0007] Some embodiments of the present technology may include a processing method. The method may include forming an oxide monolayer on a metal film, the oxide monolayer including an oxidizer gas adsorbed on the lithium film. The method may include converting the oxide monolayer to a carbonate passivation layer by reacting the oxide monolayer with a carbon source gas. The method may also include patterning the metal film with a pattern that defines a plurality of recesses.

[0008] In some embodiments, patterning the metal film may include depositing a substrate layer on a current collector, forming a pattern in the substrate layer, and depositing the metal film on the substrate layer. Forming the pattern in the substrate layer may include ablating the substrate layer with a laser. The pattern may be formed on the metal film after converting an oxide monolayer into a carbonate passivation layer. A plurality of recesses may be defined in the carbonate passivation layer. The pattern may define a plurality of recesses in the carbonate passivation layer. The plurality of recesses may expose a surface of the metal film. Patterning the metal film may include emitting a light beam from a coherent light source. Patterning the metal film may include receiving the light beam with a diffractive optical element. The diffractive optical element may be configured to reshape the light beam and redirect the light beam onto the metal film. Patterning the metal film may also include illuminating the metal film at a plurality of locations corresponding to the pattern. Patterning the metal film can include advancing the metal film between two or more rollers. A first roller of the two or more rollers can be or include a microneedle array. The microneedle array can be configured to transfer the pattern to the metal film. A second roller of the two or more rollers can support the metal film against the first roller.

[0009] Some embodiments of the present technology may include a passivation system. The system may include a plurality of rollers. The rollers may be configured to hold a conductive substrate in tension while the conductive substrate advances across a span between two of the plurality of rollers. The system may include a first showerhead positioned within the span, the first showerhead configured to deliver a first gas to the conductive substrate. The system may also include a second showerhead positioned within the span, the second showerhead configured to deliver a second gas to the conductive substrate. The first showerhead and the second showerhead may be aligned in a plane parallel to a plane between the two rollers. Each showerhead may define a flow pattern that substantially maintains a gas delivered within a region between the showerhead and the conductive substrate.

[0010] In some embodiments, the first showerhead and the second showerhead can each include a plurality of inlets and a plurality of outlets in an arrangement, where the plurality of outlets are positioned to remove excess gas from a region between the plurality of outlets and the lithium film, and the orientation of the plurality of outlets defines a flow pattern. The plurality of inlets and the plurality of outlets may be equal in number. The first showerhead and the second showerhead can each include a gas inlet configured to receive gas from a gas supply system. The first showerhead and the second showerhead can each include a top plate. The top plate can include a plurality of conduits communicating with the gas inlets. The first showerhead and the second showerhead can each include a bottom plate. The bottom plate can include a plurality of inlets and a plurality of outlets. The plurality of inlets can communicate with the plurality of conduits. The first showerhead and the second showerhead can also each include a gas outlet communicating with the plurality of outlets and configured to send excess gas to a gas exhaust system. The first showerhead and the second showerhead can each include a heated baffle. The first showerhead can include a first plurality of showerhead units oriented along a first axis, and the second showerhead can include a second plurality of showerhead units oriented parallel to the first axis and offset a first distance from the first showerhead.

[0011] Such techniques can provide many advantages over conventional systems and techniques. For example, the system can provide passivated thin films for incorporation into multilayer batteries. In this manner, operation of embodiments of the present technology can produce improved thin film coatings that can be incorporated into battery devices with improved battery performance and increased battery life. These and other embodiments, along with many of their advantages and features, are described in more detail below in conjunction with the description and accompanying drawings.

[0012] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and drawings. [Brief explanation of the drawings]

[0013] [Figure 1] 1 shows a schematic cross-sectional view of an exemplary processing chamber in accordance with some embodiments of the present technique; [Figure 2] 1 illustrates exemplary operations in a deposition method according to some embodiments of the present technique. [Figure 3A-3C] 1 shows a schematic diagram of an exemplary deposition system in operation in a deposition method according to some embodiments of the present technique; [Figures 4A-4C] FIG. 1 shows a schematic diagram of an exemplary deposition system in accordance with some embodiments of the present technique. [Figures 5A-5C] 1 shows a schematic diagram of an exemplary patterning system in operation during a deposition method according to some embodiments of the present technique;

[0014]

[0018] Some of the drawings are included as schematic diagrams. It should be understood that the figures are for illustrative purposes only and should not be considered to scale unless specifically stated to be to scale. Furthermore, as schematic diagrams, the figures are provided merely to aid understanding and may not include all aspects or information compared to realistic representations, and may be exaggerated for illustrative purposes.

[0015]

[0019] In the accompanying drawings, similar components and / or features may be marked with the same reference numeral. Further, various components of the same type may be distinguished by following the reference label with a letter that distinguishes the similar components. When only the first reference numeral is used in this specification, the specification applies to any similar components having the same first reference numeral, regardless of the letter. DETAILED DESCRIPTION OF THE INVENTION

[0016]

[0020] In roll-to-roll manufacturing processes for metal or other multilayer materials, surface passivation can involve introducing one or more precursor gases into the region between the showerhead or gas distributor and the substrate support. As the precursors interact, the deposited material can form a passivation layer on the substrate. When precursor gases are formed by surface-mediated reactions, a passivation layer can develop on any surface exposed to the gas. Thus, it is important to control contamination of roll-to-roll deposition systems by precursor gases. Furthermore, passivation layers can limit the effectiveness of the multilayer material as a conductor, which can result in the multilayer material incorporating patterns formed by processes such as pressing, stamping, or rolling.

[0017]

[0021] Previous techniques have addressed these limitations by separating the passivation process from the roll-to-roll deposition unit, but moving the roll from one unit to another can involve multiple, complex transport operations. Furthermore, mechanical patterning approaches increase the risk of contaminating or damaging the multilayer film, especially as film thicknesses decrease as roll-to-roll manufacturing technology advances. The present technique overcomes these limitations by integrating passivation into the roll-to-roll deposition system using a gas delivery system that defines a flow pattern in which a substantially negligible volume of precursor gas leaves the region between the substrate and the gas delivery system. Furthermore, the present technique overcomes the limitations of the passivation system by incorporating a patterning process into the roll-to-roll deposition system. In this manner, the substrate and / or passivation layer are patterned. For example, a first precursor gas may be adsorbed onto the surface of the metal film as a monolayer, achieved by a showerhead configured to recapture substantially all of the first precursor gas. Following the provision of the first precursor gas, a second precursor gas can be provided by a second showerhead similarly configured to recapture all of the first precursor gas. This allows the second precursor gas to react with the adsorbed monolayer of the first precursor gas to form a passivation layer while maintaining a substantially negligible presence of either the first or second precursor gas in the roll-to-roll deposition system. Before or after the formation of the passivation layer, the substrate can be patterned by one or more methods (including, but not limited to, laser patterning or impressing with a laser-machined roller) to define an array of recesses in the surface of the substrate and / or passivation layer. After describing the general aspects of a chamber capable of deposition and patterning according to embodiments of the present technology, specific methodologies and component configurations can be discussed. It should be understood that the present technology is not intended to be limited to the specific films and processes discussed.The techniques described herein can be used to improve numerous film formation processes and are applicable to a variety of processing chambers and operations.

[0018]

[0022] FIG. 1 shows a cross-sectional view of an exemplary processing chamber 100 according to some embodiments of the present technique. Further exemplary embodiments will be discussed with reference to the diagram of FIG. 1. This drawing illustratively depicts various possible embodiments of a flexible substrate coating apparatus 100. The terms "coating" and "depositing" are used interchangeably herein. While not limited to this embodiment, a flexible substrate coating apparatus may generally be configured to accommodate a substrate storage spool 110, as shown in the embodiment of FIG. 1. According to some embodiments (which may be combined with other embodiments described herein), a flexible substrate 140 to be processed may be provided on the storage spool 110. The storage spool may be disposed in a separate spool chamber 70. An interleaf 706 may also be provided between adjacent layers of the flexible substrate 140 to reduce direct contact between one layer of the flexible substrate 140 and an adjacent layer of the flexible substrate 140 on the storage spool 110.

[0019]

[0023] In operation, flexible substrate 140 may be unwound from storage spool 110, as indicated by the direction of substrate movement indicated by arrow 108. As flexible substrate 140 is unwound from storage spool 110, interleaf 706, if present, may be wound onto interleaf roll 766. Flexible substrate 140 may be guided via one or more guide rollers 104. Flexible substrate 140 may also be guided by one or more substrate guide control units 10, which control the travel of flexible substrate 140, for example, by fine-tuning the orientation of flexible substrate 140.

[0020]

[0024] A coating drum 114 may be provided within the vacuum processing chamber 60. After the flexible substrate 140 is unwound from the storage spool 110 and travels over the guide rollers 104 and the flexible substrate 140 guide control unit 10, the flexible substrate 140 may be provided on the coating drum 114 and transported through a processing region 730 corresponding to the location of the deposition unit 680. In operation, the coating drum 114 rotates such that the flexible substrate 140 is transported in the direction of arrow 108.

[0021]

[0025] Following deposition by the deposition unit 680, the flexible substrate 140 is cleaned by the cleaning unit 150. Accordingly, (not limited to any embodiment), the cleaning unit 150 is typically positioned within the vacuum processing chamber 60. In particular, (not limited to this embodiment), the cleaning unit may be positioned to act on the flexible substrate 140 while it is still positioned on the drum. Thus, cleaning may be a process step performed in the process section of the coating drum. This advantageously allows a defined contact pressure of the cleaning unit to be applied to the flexible substrate 140. Alternatively, the cleaning unit may be positioned within the free span of the flexible substrate 140 between the coating drum and the next guide roller. In this manner, two cleaning units may be provided, one on each side of the flexible substrate 140.

[0022]

[0026] In the diagram of FIG. 1 , the flexible substrate 140 can be cleaned by the cleaning unit 150 immediately after the final deposition process while still on the coating drum. Additionally, the flexible substrate 140 can be cleaned before contacting the deflection roller 14. In other words, the design of the flexible substrate coating apparatus can include a cleaning unit as the first element in the flexible substrate coating apparatus that touches the coating side of the flexible substrate 140 downstream of the deposition process. In this way, substrate damage, as described above, can be substantially reduced when the substrate contacts the deflection roller. If particulate contaminants are present on the substrate, contact with the deflection roller 14 can press the contaminants into the substrate. This can imprint particle footprints on the substrate, leading to pinholes, etc.

[0023]

[0027] The vacuum processing chamber 60 may be maintained at a high vacuum to optimize deposition quality and reduce contamination by foreign particles in the deposited layer. In particular, deposition equipment (e.g., those with CVD, PECVD, and / or PVD sources) may use different residuals from the gas mixture. Contamination by unknown or unwanted vapors from the cleaning unit may impair the long-term stability of the deposition process. After being cleaned by the cleaning unit 150, the flexible substrate 140 may run over one or more deflection rollers 14. The one or more deflection rollers 14 downstream of the coating and cleaning units may also function as tensioning units, allowing the substrate 140 to have a different tension during deposition than during winding.

[0024]

[0028] Additionally, the flexible substrate 140 may run over one or more flexible substrate 140 guide control units 10 and additional rolls (e.g., guide rollers 104 shown in FIG. 1). As the flexible substrate 140 coating in the embodiment of FIG. 1 is accomplished in situ, the flexible substrate 140 is wound onto a spool 764. To reduce damage to the web, additional interleaves 706 may be provided between layers of the flexible substrate 140 from an interleaf roll 767.

[0025]

[0029] The flexible substrate 140 can be coated with one or more thin films. For example, one or more layers can be deposited on the flexible substrate 140 by a deposition unit 680. The deposition occurs while the substrate is guided over the coating drum 114. Three, four, five, or more deposition units can be provided that can be positioned around the coating drum 114. Each deposition unit 680 can be connected to a corresponding control and / or power supply unit 690.

[0026]

[0030] The embodiments described herein refer, inter alia, to a plasma deposition system for depositing a thin film on a moving substrate from a plasma phase. The flexible substrate 140 may move in a substrate transport direction within a vacuum processing chamber, in which a plasma deposition unit is disposed for delivering a deposition gas to the plasma phase and for depositing a thin film on the moving substrate from the plasma phase. In this way, cleaning can also be performed on the moving flexible substrate 140.

[0027]

[0031] 1, one or more plasma deposition units, such as deposition unit 680, may be implemented as a PECVD (plasma enhanced chemical vapor deposition) source having a multi-region electrode device including two, three, or even more RF (radio frequency) electrodes positioned opposite the moving flexible substrate 140. According to embodiments, the multi-region plasma deposition unit may also be implemented for MF (medium frequency) deposition.

[0028]

[0032] Generally, the one or more deposition units described herein can be selected from the group consisting of CVD sources, PECVD sources, and PVD sources. The one or more deposition units can be sputtering sources, such as magnetron sputtering sources, DC sputtering sources, AC sputtering sources, pulsed sputtering sources, radio frequency (RF) sputtering, or medium frequency (MF) sputtering. For example, MF sputtering can be performed at a frequency in the range of 5 kHz to 100 kHz, e.g., 30 kHz to 50 kHz. According to a typical implementation, the flexible substrate coating apparatus can be used in the manufacture of flexible TFT displays, particularly barrier layer stacks for flexible TFT displays.

[0029]

[0033] In the illustrated embodiment, traveling over the coating drum 114, the flexible substrate 140 may pass through two or more processing regions 730, each positioned opposite a deposition unit 680 (e.g., a sputtering or evaporation source), as shown in FIG. 1 . A flexible substrate coating apparatus may include more than one coating unit, for example, more than one coating drum 114. The flexible substrate 140 may be coated with one or more thin films, whereby one or more layers may be deposited on the flexible substrate 140 by the deposition unit 680. Deposition may occur while the flexible substrate 140 is guided over the coating drum 114. A flexible substrate 140 guide control unit may be provided on one or both sides of the coating drum. The flexible substrate 140 guide control unit may be configured to measure and adjust web tension. In this manner, transport of the flexible substrate 140 may be better controlled, the pressure of the substrate on the coating drum may be controlled, and / or damage to the substrate may be reduced.

[0030]

[0034] As shown in FIG. 1 , the flexible substrate coating apparatus can include one or more seals, such as seal 290. The seals can be static seals. The seals can provide pressure isolation between the vacuum process chamber 60, including the coating drum 114, and the spool chambers 70 and 80 (where the flexible substrate 140 can be guided, wound, and / or unwound). Such a setup reduces the complexity of replacing the spool 764 after it has been fully coated. This, among other things, allows the vacuum process chamber 60 to be maintained at a medium / high vacuum while having ambient pressure or a low vacuum in the flexible substrate 140 handling chamber. Notably, the one or more seals can also generally be dynamic seals, such as seals that are operable during web movement.

[0031]

[0035] The flexible substrate coating apparatus 100 may include guide rollers 104 within the vacuum process chamber 60 or the spool chambers 70 and 80, where the guide rollers define one or more spans 160. The spans 160 may provide space for the introduction of additional coating and processing units (described below with reference to FIGS. 2-6). For example, the spans 160 within the vacuum process chamber 60 or the spool chambers 70 and 80 may enable the integration of a deposition unit capable of transporting the flexible substrate 140 beneath one or more gas showerheads (described below with reference to FIGS. 2-4). In another example, the spans 160 may enable the integration of a patterning unit, where a pattern may be introduced into the surface of the flexible substrate 140, for example, by optical patterning or mechanical patterning. In some embodiments, the flexible substrate 140 may be conductive.

[0032]

[0036] 2 illustrates exemplary operations in a deposition method 200 in accordance with some embodiments of the present technique. The method may be performed in a variety of processing chambers, including the processing chamber 100 described above. Additional aspects of the processing chamber 100 are described further below. The method 200 may include several optional operations, which may or may not be specifically associated with some embodiments of the method in accordance with the present technique. For example, many operations are described to provide a broader scope (not critical to the technique) for structure formation, or may be performed by alternative methodologies that will be readily understood.

[0033]

[0037] Method 200 may include additional operations prior to the commencement of the recited operations. For example, the additional processing operations may include forming structures on a flexible and / or conductive substrate, which may include both the formation and removal of materials. Prior processing operations may occur within the chamber in which method 200 may be performed, or processing may occur in one or more other processing chambers before delivering the substrate to the substrate processing chamber in which method 200 may be performed. In either case, method 200 may optionally include delivering the substrate to a processing volume of a vacuum processing chamber (e.g., processing chamber 100 described above) or other chamber that may include the components described above. Method 200 describes the operations shown generally in FIGS. 3A-C, and these illustrations will be described in connection with method 200. It should also be understood that FIG. 3 shows only a partial schematic diagram, and that a processing system may include the subsystems shown, as well as alternative subsystems of any size or configuration that can still benefit from aspects of the present technology.

[0034]

[0038] 3A-3C show schematic diagrams of an exemplary processing system operating in a processing method according to some embodiments of the present technology. FIGS. 3A-3C may show additional details regarding components within chamber 100. System 300 may be understood to include any feature or aspect of chamber 100 discussed above in some embodiments. System 300 may be used to perform roll-to-roll coating of substrate films. System 300 may show a partial view of the discussed chamber components that can be incorporated into a flexible substrate coating system, or may show a view of a flexible substrate between two rollers, or may otherwise be of any size. Any aspect of system 300 may be incorporated into other processing chambers or systems, as would be readily understood by one skilled in the art.

[0035]

[0039] In operation 205, as illustrated in FIG. 3A , the deposition procedure may optionally include depositing a material film 305 on a conductive substrate 310, which may be an example of flexible substrate 140 in FIG. 1 . Material film 305 may be or include a metal suitable for applications in thin-film structures (including, but not limited to, multilayer batteries, transparent electrodes, optically active films, or other functional thin-film materials). In the illustrated example, material film 305 may be or include lithium metal, which may be deposited by a method compatible with chamber 100 (described in more detail above with reference to FIG. 1 ). For example, lithium metal may be deposited on conductive substrate 310 by thermal evaporation. In some embodiments, for example, material film 305, as deposited, includes surface features that exceed a uniformity threshold for application in subsequent operations of method 200. In this manner, operation 205 may further include planarizing material film 305. Planarization may include, but is not limited to, any method compatible with chamber 100 and integrable into a roll-to-roll manufacturing system. For example, a laser planarization approach may be applied to reduce the characteristic dimensions of surface features of material film 305. Laser planarization may include directing a laser beam 315 toward the surface of material film 305. Laser beam 315 may be or include a high-frequency pulsed infrared laser beam, for example, with a pulse period on the order of picoseconds or femtoseconds. Laser beam 315 may be or include a visible laser beam with a frequency on the order of MHz. In some embodiments, laser beam 315 may be focused onto the surface of material film 305 through a transparent plate 320 and scanned across the surface of material film 305. Transparent plate 320 may contain a laser-induced plasma between the surface of material film 305 and transparent plate 320, whereby the plasma includes vapor of material film 305 that can be redeposited on the surface of material film 305 as laser light 315 scans.In this manner, the laser beam 315 may gradually planarize the material film 305 over multiple scans, for example, as the conductive substrate 310 may be translated beneath the position of the laser beam 315 .

[0036]

[0040] In some embodiments, method 200 may include, in operation 210, transporting material film 305 below a first showerhead 325. The first showerhead 325 may be integrated into a processing chamber, e.g., chamber 100, so as to be positioned within the span of conductive substrate 310 travel, e.g., between two guide rollers 104 of FIG. 1 . The conductive substrate 310 may travel past the first showerhead, carrying the material film 305 therewith. In this manner, material film 305 may be transported below the first showerhead at a rate equivalent to the travel speed of conductive substrate 310, over a distance between the surface of material film 305 and a proximal surface of first showerhead 325. Furthermore, distance 330 may define a region between first showerhead 325 and the surface of material film 305. 4A-4C, the first showerhead 325 can include internal structures that define a flow pattern that substantially maintains the delivered gas within the region between the showerhead and the conductive substrate. In some embodiments, the span in which the first showerhead is positioned can be oriented substantially vertical, substantially horizontal, or at any angle therebetween, with the term "downward" indicating facing the proximal surface of the first showerhead 325, rather than any particular orientation of the showerhead.

[0037]

[0041] In some embodiments, the method 200 may include, in operation 215, introducing a first gas through the first showerhead 325. The first gas may be or include an oxidizer gas (including, but not limited to, diatomic oxygen, water vapor, or another gas selected for its surface binding energy that results in a monolayer adsorbed on the surface of the material film 305 and reacts with the carbon source to form a carbonate). As described above, the first showerhead 325 may include internal structure that enables the first showerhead 325 to introduce the first gas according to a flow pattern that restricts excess gas flow parallel to the lithium film outside the region between the material film 305 and the proximal surface of the first showerhead 325. In some embodiments, the first gas may be or include an inert gas, similar to the oxidizer gas. For example, the first gas can be or can include a mixture of an inert carrier gas and an oxidizer, where the oxidizer is present in the inert carrier gas at a concentration of greater than or equal to 0.5 ppm, greater than or equal to 1.0 ppm, greater than or equal to 1.5 ppm, greater than or equal to 1.5 ppm, greater than or equal to 2.0 ppm, greater than or equal to 2.5 ppm, greater than or equal to 3.0 ppm, greater than or equal to 3.5 ppm, greater than or equal to 4.0 ppm, greater than or equal to 4.5 ppm, greater than or equal to 5.0 ppm, greater than or equal to 5.5 ppm, greater than or equal to 6.0 ppm, greater than or equal to 6.5 ppm, greater than or equal to 7.0 ppm, or greater. The flow rate of the inert carrier gas may be selected to provide the oxidizer at a flow rate below 0.1 sccm.The inert carrier gas can be or can include argon and can be provided to the first showerhead at a flow rate of greater than or equal to about 1 slm, greater than or equal to about 10 slm, greater than or equal to about 20 slm, greater than or equal to about 30 slm, greater than or equal to about 40 slm, greater than or equal to about 50 slm, greater than or equal to about 60 slm, greater than or equal to about 70 slm, greater than or equal to about 80 slm, greater than or equal to about 90 slm, greater than or equal to about 100 slm, greater than or equal to about 110 slm, greater than or equal to about 110 slm, greater than or equal to about 120 slm, or more.

[0038]

[0042] Exemplary embodiments of the first showerhead 325 are provided in FIGS. 4A-C. In some embodiments, the showerhead 400 can include internal structures that enable the showerhead to deliver a first gas to the material film 305 according to a flow pattern. As shown in FIG. 4A, the showerhead 400 can include a gas inlet 405, which can be connected to a gas supply. The gas supply can include one or more gas manifold elements that enable the showerhead 400 to deliver the first gas with a controlled oxygen composition. For example, the gas supply can include an inert gas supply, an oxygen gas supply, and a water vapor supply, such as a water bubbler that can deoxygenate by scrubbing a water reservoir with an inert gas. The showerhead 400 can include an inlet plenum 410 configured to deliver the first gas to a top plate 415. As shown in FIG. 4B, the top plate 415 can include an array of conduits 420 extending between the top plate 415 and a bottom plate 425. The base plate 425 can include an array of inlets 430 and an array of outlets 435. The conduits 420 can extend through the inlets 430 to a distance beyond the surface of the base plate 425. The surface of the base plate 425, together with the conduits 420, can define a proximal surface of the showerhead 400, as defined in relation to a conductive substrate, for example, when the showerhead 400 is integrated into a roll-to-roll processing system, such as the chamber 100 of FIG.

[0039]

[0043] As shown, the array of outlets 435 can be in communication with an exhaust plenum 440 within the showerhead 400. The exhaust plenum 440 can be configured to operate at a reduced pressure relative to a region behind the proximal face of the showerhead 400, provided by outlets 445 in communication with an exhaust system. In this manner, during operation 215, a first gas can be provided through the conduits 420 and recaptured by the exhaust plenum 440 via outlets 435 in the base plate 425. In some embodiments, the base plate 425 can include an equal number of inlets 430 and outlets 435. The relative number of inlets 430 and outlets 435 can vary based on, for example, the operating parameters that result in the flow pattern defined by the showerhead 400. In general, an arrangement of the inlets and outlets can be specified to define a flow pattern of gas delivered through the conduits that substantially maintains the delivered gas within the region between the showerhead 400 and the conductive substrate 310. For example, the delivered gases can be restricted to flow parallel to the conductive substrate 310 outside the region between the showerhead 400 and the conductive substrate 310 .

[0040]

[0044] In some embodiments, the showerhead 400 can include a heated baffle 450. The heated baffle can be configured to increase the temperature of the gas provided through the conduit 420. For example, the adsorption dynamics of the gas can be temperature dependent. In this manner, the heated baffle 450 can enable the showerhead to provide the gas to the surface of the material film 305 at a controlled temperature. The controlled temperature can be defined to promote the formation of a monolayer 335, as opposed to other forms of adsorption (e.g., multilayer adsorption or unsaturated surface adsorption).

[0041]

[0045] Following the introduction of the first gas through the first showerhead 325, the method 200 may include, in operation 220, transferring the material film 305 below the second showerhead 340. As described in connection with operation 210, the second showerhead 340 may be positioned within the span in which the conductive substrate 310 travels between two rollers of a roll-to-roll processing system. The second showerhead 340 may be positioned a distance 350 from the first showerhead 325 in the direction of travel of the conductive substrate 310. The distance 350 between the first showerhead 325 and the second showerhead 340 may correspond to the time it takes for the monolayer 335 to reach equilibrium with respect to the rate of travel of the conductive substrate 310. Transferring the material film 305 below the second showerhead 340 may also result in a residence time below the second showerhead 340, which may be coupled with gas flow parameters of the second showerhead. In this manner, the operation of the second showerhead can be controlled to effect a chemical reaction between the second gas and the monolayer 335 .

[0042]

[0046] As shown in FIG. 3C , the first showerhead 325 can include multiple first showerhead units 355. Each of the first showerhead units 355 can include the internal structure described in connection with FIGS. 4A-4C and can be oriented along an axis perpendicular to the direction of travel of the conductive substrate 310. In this manner, the first showerhead 325 can be modularized and scalable to process different widths of the conductive substrate 310. Similarly, the second showerhead 340 can include multiple second showerhead units 360. The second showerhead units 360 can be oriented parallel to the axis and offset from the first showerhead by a distance 350. In this manner, transferring the material film 305 may include advancing the conductive substrate 310 carrying the material film 305 beneath the first showerhead unit 355 and then beneath the second showerhead unit 360 in a direction perpendicular to the alignment axis of the first showerhead unit 355 and the second showerhead unit 360.

[0043]

[0047] In some embodiments, method 200 may include, in operation 225, introducing a second gas through the second showerhead 340. Operation 225 may be performed simultaneously with operation 220, such that the second gas is provided to the material film 305 while the material film 305 is transported beneath the second showerhead 340. As described in more detail in connection with operation 215, the second gas may be provided through the second showerhead 340 at a controlled temperature and according to a flow pattern defined by the second showerhead 340 resulting from an arrangement of inlets and outlets within the second showerhead 340. The second gas may be or include a carbon source gas selected to react with the monolayer 335 to form the passivation layer 345. For example, the second gas may be or include carbon dioxide. The second gas may include carbon dioxide and an inert carrier gas. The second gas can comprise carbon dioxide at or above 1% by volume, at or above 5% by volume, at or above 10% by volume, at or above 20% by volume, at or above 30% by volume, at or above 40% by volume, at or above 50% by volume, at or above 60% by volume, at or above 70% by volume, at or above 80% by volume, at or above 90% by volume, at or above 95% by volume, or more. The inert carrier gas can be or can include argon or nitrogen.

[0044]

[0048] Following or simultaneously with introducing the second gas through the second showerhead 340, the method 200 may include passivating the material film 305 in operation 230. As described above, passivating the material film 305 may describe a process in which the monolayer 335, including the oxygen species, reacts with the second gas to form the passivation layer 345. The passivation layer may be or may include a carbonate formed from the material film 305. For example, if the material film is or includes lithium metal, the passivation layer 345 may be or may include lithium carbonate. The passivation of operation 230 may include a heterogeneous reaction at the surface of the material film 305 that converts the monolayer 335 into the passivation layer 345.

[0045]

[0049] At one or more points during method 200, an operation may include patterning material film 305 and / or passivation layer 345 in operation 235. To that end, while method 200, as illustrated in FIG. 2, describes operations in a particular order, operation 235 may be performed in a different order or timing, as illustrated in FIGS. 5A-5C. In some embodiments, patterning may include patterning material film 305. As illustrated in FIG. 5A, substrate 505 may be deposited on conductive substrate 310. The substrate may be or include a material compatible with deposition processes in a roll-to-roll manufacturing system, as described in connection with FIG. 1. For example, substrate 505 may be or include a Group IV or Group IV suboxide. Substrate 505 may be or include silicon or silicon oxide. Subsequently, substrate 505 may be irradiated with light beam 510. The light beam 510 can be or can include a coherent light beam (e.g., a laser) selected to ablate the surface of the material film 305. For example, the light beam 510 can be generated by a pulsed laser light source to ablate the surface of the substrate 505 and define a plurality of recesses 520 in the film surface of the substrate 505. The light beam 510 can be directed toward an optical system 515, which can be or can include a diffractive optical element. The optical system 515 can reshape the light beam 510 to remove material from the substrate 505, and can define prismatic recesses in the substrate 505 as the conductive substrate 310 advances past the optical system 515. In this manner, the recesses 520 can function as a patterned surface that will transfer the pattern to the material film 305 and the passivation layer 345.

[0046]

[0050] In some embodiments, method 200 may include operation 235 following operation 230. As shown in FIGS. 5B-5C, method 200 may include patterning passivation layer 345. As shown in FIG. 5B, light beam 510 and optics 515 may be positioned such that conductive substrate 310 travels past the position of optics 515 following the formation of passivation layer 345, and such that light beam 510 can remove material from passivation layer 345 to define recess 520. Light beam 510 may be or may include a pulsed laser beam configured to be absorbed by passivation layer 345, thereby ablating passivation layer 345 relative to material film 305. In this manner, passivation layer 345 may be patterned to expose material film 305 below passivation layer 345.

[0047]

[0051] Similarly, as shown in FIG. 5C , operation 235 can include patterning the passivation layer 345 using one or more rollers integrated into the roll-to-roll system described in connection with FIG. 1 . The first roller 525 can be machined with a negative pattern. For example, the first roller 525 can include a microneedle array configured to transfer the pattern to the surface of the passivation layer 345 or the material film 305. For example, application of pressure to the first roller 525 can transfer the pattern of the recesses 520 to the underlying passivation layer 345 and the underlying material film 305. In some embodiments, pressure can be applied by a second roller 530 located substantially opposite the first roller 525, supporting the conductive substrate 310 against the first roller 525. In this way, the force applied to the material film 305 or passivation layer 345 can be controlled by the force that the first roller 525 applies to the second roller 530 or by the tension applied to the conductive substrate 310 by the first roller 525.

[0048]

[0052] Utilizing methods and components according to embodiments of the present technology can improve the deposition or formation of materials. By delivering precursor gases to substrates in flexible substrate coating apparatuses through showerheads configured to limit contamination from excess gases, the overall performance and quality of deposited films can be improved. These improvements can include reduced precursor gas waste (if the gases are recyclable) and reduced contamination of sensitive films (e.g., oxidation-sensitive metal films) in the early stages of deposition. Furthermore, substrate patterning can improve device performance, for example, by placing surface active sites for dendrite formation within recesses in the passivation layer, thereby limiting the impact of dendrites on battery life and operational performance. Furthermore, incorporating the technology described herein into flexible substrate coating systems can provide significant improvements for process integration, resulting in improved throughput, for example, allowing for the production of in-situ passivated metal films on conductive substrates.

[0049]

[0053] In the foregoing specification, for purposes of explanation, numerous details are set forth in order to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that particular embodiments may be practiced without some of these details or with additional details.

[0050]

[0054] Having disclosed several embodiments, those skilled in the art will recognize that various modifications, alternative configurations, and equivalents may be used without departing from the spirit of the present embodiments. Moreover, to avoid unnecessarily obscuring the present technology, many well-known processes and elements have not been described. Thus, the above description should not be construed as limiting the scope of the technology. Furthermore, while a method or process may be described as sequential or in steps, it should be understood that the operations can be performed simultaneously or in a different order than listed.

[0051]

[0055] Where a range of values ​​is disclosed, unless the context clearly dictates otherwise, it is understood that each intervening value between the upper and lower limits of that range, to the smallest fraction of the unit of the lower limit, is specifically disclosed. Narrower ranges between any stated or unstated intervening value in a stated range and any other stated or intervening value in that stated range are encompassed. The upper and lower limits of these smaller ranges may independently be included or excluded, and each range where either or both limits are included in the smaller range is also encompassed within the technology (except as specifically excluded within a stated range). When a stated range includes one or both of the endpoints, ranges excluding either or both of those included endpoints are also included.

[0052]

[0056] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise. Thus, for example, reference to "a precursor" includes a plurality of such precursors, reference to "the layer" includes reference to one or more layers and equivalents thereof known to those skilled in the art, and so forth.

[0053]

[0057] Additionally, the terms "comprise," "comprising," "contain," "containing," "include," and "including," when used in this specification and the claims that follow, are intended to specify the presence of stated features, integers, components, or operations, but do not exclude the presence or addition of one or more other features, integers, components, operations, acts, or groups.

Claims

1. 1. A method for treating a lithium membrane, comprising: transporting the lithium film under the first showerhead; introducing an oxidizer gas onto the lithium film through the first showerhead, the oxidizer gas being mixed with an inert carrier gas such that the oxidizer gas is provided at a flow rate of less than 0.1 sccm; forming an oxide monolayer on the lithium film, the oxide monolayer including the oxidizer gas adsorbed on the lithium film; transferring the lithium film under a second showerhead after forming the oxide monolayer; introducing a carbon source gas onto the lithium film through the second showerhead; and converting the oxide monolayer into a carbonate passivation layer by reacting the oxide monolayer with the carbon source gas; A method comprising:

2. 10. The method of claim 1, wherein the lithium film is supported on a conductive substrate held in tension between two tension elements of a film deposition system.

3. depositing lithium onto the conductive substrate; and planarizing the deposited lithium; The method of claim 2 further comprising:

4. the first showerhead includes a first plurality of showerhead units oriented along a first axis; the second showerhead includes a second plurality of showerhead units oriented parallel to the first axis and offset a first distance from the first showerhead; 10. The method of claim 1, wherein transporting the lithium film under the first showerhead comprises movement orthogonal to the first axis.

5. 2. The method of claim 1, wherein the first showerhead and the second showerhead each comprise a plurality of inlets and a plurality of outlets in an arrangement positioned to remove excess gas from a region between the plurality of outlets and the lithium film, and an orientation of the plurality of outlets defines a flow pattern that restricts excess gas flow parallel to the lithium film outside the region.

6. forming a pattern on the surface of the lithium film that defines a plurality of recesses on the surface of the lithium film; The method of claim 1 further comprising:

7. forming a pattern in the carbonate passivation layer that defines a plurality of recesses in the carbonate passivation layer; 2. The method of claim 1, further comprising: wherein the plurality of recesses expose a surface of the lithium film.

8. 1. A method for treating a metal film, comprising: forming an oxide monolayer on a metal film comprising an oxidizer gas adsorbed on the metal film, the oxidizer gas being mixed with an inert carrier gas such that the oxidizer gas is provided at a flow rate of less than 0.1 sccm; converting the oxide monolayer into a carbonate passivation layer by reacting the oxide monolayer with a carbon source gas; and patterning the metal film with a pattern that defines a plurality of recesses. A method comprising:

9. patterning the metal film, depositing a substrate layer onto a current collector; forming the pattern on the substrate layer; and depositing said metal film on said substrate layer; The method of claim 8, comprising:

10. The method of claim 9 , wherein forming the pattern in the substrate layer comprises ablating the substrate layer with a laser.

11. 9. The method of claim 8, wherein after converting the oxide monolayer into the carbonate passivation layer, the pattern is formed on the metal film, and the plurality of recesses are defined in the carbonate passivation layer.

12. 12. The method of claim 11, wherein the pattern defines the plurality of recesses in the carbonate passivation layer, the plurality of recesses exposing a surface of the metal film.

13. patterning the metal film, emitting a beam of light from a coherent light source; directing the light beam towards a diffractive optical element configured to reshape the light beam and redirect the light beam towards the metal film; and irradiating the metal film at a plurality of locations corresponding to the pattern; The method of claim 11 , comprising:

14. patterning the metal film, advancing the metal film between two or more rollers; 9. The method of claim 8, wherein a first roller of the two or more rollers includes a microneedle array configured to transfer the pattern to the metal film, and a second roller of the two or more rollers abuts the first roller to support the metal film.

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