Apparatus and method for thin film deposition

Abstract

A thin film deposition system includes a modular reactor head, a substrate stage, and a modular reactor head positioning system. The modular reactor head positioning system positions the modular reactor head relative to the substrate to deliver precursor gas to the substrate positioned on the substrate stage. The modular reactor head includes a set of modular components that perform different functions and can be placed in different configurations.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to U.S. Provisional Application No. 62 / 949,798, filed on December 18, 2019, which is hereby incorporated by reference. Technical Field

[0003] The present disclosure relates generally to thin film deposition, and more particularly to apparatus and methods for thin film deposition. Background Art

[0004] Techniques such as sputtering, evaporation, and chemical vapor deposition are used to deposit films for many applications such as modern electronics, optical components, display technology, food packaging, etc. For these applications, there is a need for improved control over film thickness. Atomic layer deposition (ALD) is the best technology for producing films with nanometer-scale thickness control because it deposits the film one atomic layer at a time. With the continuous reduction in feature sizes in applications such as integrated circuits and memory devices, ALD is becoming the preferred (and only in some cases) choice for depositing some film components. Weaknesses associated with traditional ALD include its speed (it is a relatively slow batch process) and its need for a vacuum chamber, which hinders its scalability.

[0005] Conventional time ALD operates by inserting two or more chemical precursor gases sequentially into a vacuum chamber, with evacuation and purge steps between exposures. If the right experimental conditions are used, a single atomic layer of material is formed after each sequence, and the sequence is repeated multiple times to build a film. Therefore, conventional time ALD separates the two precursor gases in time. In contrast, spatial atomic layer deposition (SALD) technology has been developed that separates the two precursors in space rather than time. The substrate moves between the two precursor gases to replicate the sequential exposure. This eliminates or reduces the evacuation and purge steps that slow down time ALD.

[0006] Atmospheric pressure SALD (AP-SALD) can produce thin film layers of materials (such as metal oxides) that are dense, conformal, and pinhole-free, and can deposit thin films at about room temperature. This is one to two orders of magnitude faster than conventional ALD and is scalable. Notably, AP-SALD is also compatible with roll-to-roll manufacturing and has been demonstrated for glass, glass coated with transparent conductive oxides, semiconductor wafers, foils, fabrics, and plastic surfaces. These advantages make AP-SALD very attractive for high-throughput manufacturing of large-area, low-cost electronics (such as photovoltaics, batteries, and microelectronics) as well as functional coatings (such as barrier films and antimicrobial coatings).

[0007] Therefore, a novel thin film deposition apparatus and method are provided. Summary of the invention

[0008] The present disclosure includes a novel film or thin layer deposition method, which generally includes at least one reactor head, which is modular and configurable for functional flexibility and scalability to produce thin films. Thin layer deposition can include spatial atomic layer deposition and / or chemical vapor deposition. The reactor head can include different types of components, such as but not limited to precursor gas slits, plasma sources, exhaust slits, heating channels and / or cooling channels for different types of deposition. The spacing height and width of each component can be adjusted to promote and control the flow of gas. A positioning system with a mounting element for the reactor head is configured to adjustably maintain the orientation and position of the reactor head relative to the substrate. The positioning system can be configured with at least one displacement measuring device and at least one actuator. A heating stage with suction can be used to heat the substrate and maintain substrates of different sizes, geometries and thicknesses. The heating stage can be configured with regional controlled heating to provide different temperatures at different locations. A linear motor positioning system can be used to oscillate the substrate relative to the modular reactor head. The system can deposit a thin film by spatial atomic layer deposition or chemical vapor deposition, and produce a film with uniform thickness and / or composition or different thickness and / or composition.

[0009] In one aspect of the present disclosure, a modular reactor head for use with a thin film deposition system is provided, the modular reactor head comprising a group of modular components, wherein the group of modular components are adjacent to each other in a first direction within the reactor head; wherein the group of modular components are capable of being positioned relative to each other in a second direction, the second direction being substantially perpendicular to the first direction; wherein the group of modular components comprises at least one precursor gas modular component for depositing at least two precursor gases onto a substrate.

[0010] On the other hand, the set of modular components includes at least two precursor gas modular components. In another aspect, the at least two precursors include a reactor channel; and a reactor channel opening. In another aspect, the reactor channel opening delivers a gas or liquid material at a higher outlet velocity at one end of the reactor channel opening than at the opposite end of the reactor channel opening. On the one hand, the set of modular components includes at least one of the following: a precursor fluid component, an exhaust modular component, an inert gas modular component, a temperature control modular component, a chemical modular component, a cleaning modular component, and a plasma source modular component. In another aspect, the temperature control modular component includes a metal plate for controlling the temperature of a modular component adjacent to the temperature control modular component. In yet another aspect, the temperature control modular component includes a reactor channel for receiving a cooling liquid to cool the metal plate or receiving a heating liquid to heat the metal plate. In yet another aspect, the set of modular components is mounted at a predetermined height relative to each other. On the other hand, the precursor fluid modular component includes an actuator for controlling the deposition of a precursor fluid.

[0011] In another aspect of the present disclosure, a thin film deposition system is provided, which includes a substrate stage for supporting a substrate; a modular reactor head for depositing a thin film onto the substrate, the modular reactor head including a group of modular components, the group of modular components being adjacent to each other in a first direction within the reactor head; wherein the group of modular components are positionable relative to each other in a second direction, the second direction being substantially perpendicular to the first direction; wherein the group of modular components includes at least one precursor gas modular component for depositing at least two precursor gases onto a substrate; and a modular reactor head positioning system, the modular reactor head positioning system being used to position the modular reactor head relative to the substrate on the substrate stage.

[0012] In a further aspect, the modular reactor head positioning system comprises a linear displacement system. In yet another aspect, the linear displacement system comprises a set of displacement measurement devices; and a set of linear actuators. In yet another aspect, the modular reactor head positioning system comprises a leveling system for gap control between the modular reactor head and the substrate stage. In one aspect, the substrate stage comprises a vacuum system for holding the substrate against the substrate stage. In another aspect, the substrate stage comprises an upper plate for supporting the substrate; and a heating assembly for heating the upper plate. In yet another aspect, the substrate stage comprises a linear motor system. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] For a clear understanding of the present disclosure, some embodiments of the present disclosure are described only as examples and are not limited to the figures of the accompanying drawings, in which:

[0014] Figure 1 An embodiment of a thin layer deposition system is presented;

[0015] Figure 2 is an isometric view of an embodiment of a modular reactor head comprising a plurality of modular components;

[0016] Figure 3A yes Figure 2 A bottom view of a modular reactor head;

[0017] Figure 3B yes Figure 2 A bottom perspective view of a modular reactor head;

[0018] Figure 3C is a bottom view of a modular assembly having a plurality of slits;

[0019] Figure 4 yes Figure 2 A side view of a modular reactor head;

[0020] Figure 5A is a side view of an embodiment of a modular reactor head having a plurality of modular assemblies with adjustable spacing heights;

[0021] Figure 5B yes Figure 5A A front view of a modular reactor head;

[0022] Figure 5C yes Figure 5A An isometric view of the modular reactor head;

[0023] Figure 6 is a perspective view of an embodiment of a cooling modular assembly;

[0024] Figure 7 is a perspective view of an embodiment of a modular reactor head;

[0025] Fig. 8A is a front view of an embodiment of a thin film deposition system including a reactor head positioning system;

[0026] Figure 8B yes Fig. 8A A perspective view of a thin film deposition system;

[0027] Fig. 9A is a perspective view of an embodiment of a substrate stage;

[0028] Fig. 9B yes Fig. 9A A cross-sectional view of a substrate stage;

[0029] Fig.10 is to keep Fig. 9A A perspective view of four (4) substrates on a substrate stage;

[0030] Fig.11 is a bottom perspective view of an embodiment of an upper plate;

[0031] Figures 12A to 12B Different configurations of the heating table are shown;

[0032] Fig.13A is a schematic diagram of a reactor head having three reactor channels configured to deliver uniform flow distribution;

[0033] Fig. 13B is a schematic diagram of a reactor head having a reactor channel configured to deliver a non-uniform flow distribution;

[0034] Fig.14A is a schematic diagram of the geometry of a reactor channel with non-uniform flow distribution for an embodiment of a modular assembly;

[0035] Fig. 14B is a diagram showing computational fluid dynamics simulation results, the computational fluid dynamics simulation results showing the Fig.14A The reactor channel geometry and the flow velocity of the precursor gas along the slit outlet;

[0036] Fig. 14C is a schematic diagram of a design of an embodiment of a reactor head having a non-uniform flow distribution;

[0037] Fig.14D yes Fig. 14C Photo of the 3D printed reactor head;

[0038] Fig.15 is used Fig. 14C Photo of the zinc oxide (ZnO) film produced on the reactor head;

[0039] Fig.16A It shows that for Fig.15 Figure 1 shows a structure for measuring the thickness of a ZnO film across a substrate using a thickness gradient film;

[0040] Fig. 16B Shown from Fig.16A A graph of film thickness on a surface of a substrate;

[0041] Fig.17A is a perspective view of an embodiment of a modular assembly comprising two symmetrical halves;

[0042] Fig. 17B yes Fig.17A An exploded perspective view of the modular components of the

[0043] Fig.18 is a perspective view of an embodiment of a substrate stage mounted on a linear motor system;

[0044] Fig.19 A flow chart showing a method for depositing thin films having a modular reactor head; and

[0045] Fig. 20 A flow chart of a roll-to-roll method for depositing thin films with a modular reactor head is shown. DETAILED DESCRIPTION

[0046] The terms used herein are only used to describe specific embodiments and are not intended to limit the system or the present disclosure. As used herein, the term "and / or" includes any combination and all combinations of one or more items in the associated enumerated items. As used herein, unless the context clearly indicates otherwise, the singular forms "a / an" and "the" are intended to also include plural forms. It should be further understood that when used in this specification, the term "comprise(s) and / or comprising" specifies the presence of stated features, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or groups thereof.

[0047] Figure 1 An embodiment of a film or thin layer deposition system 100 is shown, which includes a modular reactor head 102, a reactor head positioning system 104, and a substrate stage 108 for supporting a substrate 106. In one embodiment, the reactor head positioning system 104 controls the orientation of the reactor head 102 relative to the substrate 106, such as in a linear direction, rotation along an axis, and / or the distance between the reactor head and the substrate 106. The substrate stage 108 controls the position of the substrate 106 relative to the modular reactor head 102. In operation, the modular reactor head 102 deposits a thin film of a precursor gas or material onto a substrate, which will be discussed in more detail below.

[0048] As used herein, the phrase "thin layer" or "thin film" refers to a material layer deposited by spatial atomic layer deposition (SALD) and / or spatial chemical vapor deposition (SCVD). It has been shown that by controlling the processing conditions so that the precursor gases can mix in the gas phase (not isolated from each other), chemical vapor deposition rather than atomic layer deposition can be performed. This produces a higher film deposition rate, which is advantageous for some applications, while still being able to produce conformal, pinhole-free films in which the film thickness can be precisely controlled at the nanometer level. Therefore, the phrase "thin layer deposition" refers to spatial atomic layer deposition and / or spatial chemical vapor deposition.

[0049] In the current embodiment, the modular reactor head 102, the reactor head positioning system 104 and the substrate stage 108 are positioned in the lower cabinet 110. The equipment for delivering the precursor gas to the modular reactor head is placed in the upper cabinet 112. This equipment will be well known to those skilled in the art. In one embodiment, the equipment may include equipment for generating precursor chemical gas 180, such as but not limited to bubblers and bubbler heaters, equipment for controlling gas flow rate 182, such as but not limited to mass flow controllers and equipment 184 for distributing gas, such as but not limited to valves, pipes and manifolds. In one embodiment, the precursor gas can be directly input into the upper cabinet from an external source, or it can be generated from a liquid or solid chemical by bubbling or atomizing a liquid chemical material or heating a solid chemical material. In another embodiment, instead of or with the precursor gas, the liquid can be transferred from the upper cabinet to the modular reactor head.

[0050] Figure 2 1 is an isometric view of an embodiment of a modular reactor head 102. The modular reactor head 102 includes a plurality or a group of modular components 114. In one embodiment, the modular reactor head 102 may include a group of modular components 114, whereby each modular component performs a single function to achieve thin layer deposition. In some embodiments, multiple modular components may perform the same function as other modular components, while in other embodiments.

[0051] In one embodiment, the reactor head 102 can be oriented parallel to the substrate stage 108, wherein a set of modular components 114 are adjacent to each other in a plane oriented along a first direction 128. The length of each modular component in the set of modular components 114 can be considered to extend in a second direction 126 that is substantially perpendicular to the first direction 128. The reactor head 102 can be positioned at a distance from the substrate 106, wherein the distance can be measured along a direction 130 that is substantially orthogonal to the first direction and the second direction. In some embodiments, the distance can be measured from the reactor head at an angle. Each modular component in the set of modular components 114 can perform a different function, as discussed in more detail below.

[0052] In one embodiment, Figure 2 As shown by the dashed lines in FIG. 1 , the modular assembly 114 includes a reactor channel 132 for receiving a gas or liquid and a reactor channel opening 134 (which can be considered a slit) for allowing the gas or liquid to enter or leave the reactor channel 132. The reactor channel opening generally has a length that is oriented parallel to the second direction 126, however, in alternative embodiments, the reactor channel opening can be oriented at an angle relative to the second direction 126. In some embodiments, the modular assembly 114 may not include a reactor channel opening (e.g., with respect to FIG. 1 ). Figure 6 The disclosed) may or may not include a reactor channel or a reactor channel opening, wherein the modular component may be a heating or cooling element powered by a power source. Non-exclusive examples of modular components include, but are not limited to, precursor gas components, exhaust components, inert gas components, heating components, cooling components, plasma sources, and other components according to various embodiments of the present disclosure.

[0053] If modular assembly 114 is supplied with a precursor gas that passes through modular assembly 114 from a precursor gas source to reach the substrate, modular assembly 114 can be considered as a precursor gas component and the reactor channel opening is referred to as a precursor gas. Since thin layer deposition generally requires at least two different precursor gases, at least two of the modular assemblies in the reactor head will provide the function of a precursor gas modular assembly. Alternatively, if modular assembly 114 is supplied with an inert gas, the modular assembly can be considered as an inert gas modular assembly and the reactor channel opening is referred to as an inert gas opening. If modular assembly 114 is supplied with a precursor fluid, for example, a liquid and an actuator, the modular assembly can be considered as a precursor fluid modular assembly and is used to introduce different ways of nanofabrication technology, such as but not limited to selective area deposition, slot die coating, inkjet printing or spray deposition. If modular assembly 114 is coupled to a vacuum source to draw gas into its reactor channel 132 through the reactor channel opening, modular assembly 114 can be considered as an exhaust modular assembly and the reactor channel opening is referred to as an exhaust opening. Modular assembly 114 can be considered as a thermal control modular assembly, whereby hot fluid can pass through the reactor channel. In the thermal control modular assembly, the reactor channel 132 does not include a reactor channel opening. If the thermal control modular assembly provides heat, the modular assembly can be referred to as a modular heating assembly. If the thermal control modular assembly provides cooling, the thermal assembly can be referred to as a modular cooling assembly. If plasma is introduced into the reactor channel, the modular assembly can be considered as a plasma source or a plasma modular assembly. Alternatively, if modular assembly 114 is supplied with chemicals, such as but not limited to detergents or supplied with compressed air, the modular assembly can be considered as a cleaning modular assembly if necessary and can be used to clean the reactor channel for maintenance purposes or for possible cleaning of the substrate. In an alternative embodiment, the chemical can be a reducing agent, whereby the material (such as metal) on the substrate can catalyze other materials (such as metal ion salts) due to the reducing agent. In another embodiment, the chemical can be used to carry out surface modification or etching to the substrate.

[0054] Figure 3A and 3B1 is a bottom view of a modular reactor head 102 having a reactor channel opening 134. In the current embodiment, the set of modular components 114 includes a first precursor gas component 116, a second precursor gas component 118, three inert gas components 120, six exhaust components 122, and two cooling components 124, however, it should be understood that this is only one arrangement of how the modular components may be arranged. In some embodiments, the set of modular components includes at least two precursor gas components, however, in other embodiments, one modular component may be used to deliver more than one precursor gas such that the set of modular components includes only one modular component for delivering a precursor gas.

[0055] In an embodiment of the present invention, the set of head modular assemblies 114 are arranged to effectively separate precursor gases for atomic layer deposition (ALD) by positioning at least one of the inert gas assemblies 120 and at least one of the exhaust assemblies 122 between the first precursor gas assembly 116 and the second precursor gas assembly 118. The arrangement of the modular assemblies 114 is flexible, so that in alternative embodiments, the arrangement of the modular assemblies 114 can be configured to mix precursor gases for chemical vapor deposition (CVD) (e.g., the first precursor gas assembly 116 and the second precursor gas assembly 118 can be placed directly adjacent to each other without the exhaust assembly 122 or the inert gas assembly 120 in between).

[0056] Each modular reactor assembly 114 can be positioned such that the long axis of the modular reactor assembly 114 is parallel to the second direction 126. The set of modular assemblies 114 can be arranged to position each modular assembly 114 adjacent to at least one other modular assembly 114, wherein the plurality of modular assemblies 114 extend in the first direction 128. In other words, the individual modular assemblies 114 of the modular reactor head 102 are stacked horizontally for ease of assembly. The order of the modular assemblies 114 depends on the configuration of the reactor head 102, wherein the order can be changed by changing the position (i.e., changing the order) of one or more modular assemblies 114.

[0057] The modular reactor head of the present disclosure can allow the thin film deposition system to be easily scaled by increasing the number of separate modular assemblies or by increasing the length of the reactor channel opening. By increasing the number of precursor gas modular assemblies, or by increasing the number of reactor channel openings in a modular assembly, the number of ALD cycles that occur each time a substrate passes under the modular reactor head increases. Figure 3C1 is a bottom view of a modular assembly having three slots or reactor channel openings 134, although in alternative embodiments the modular assembly may have two, four, or more slots 134. Each slot 134 may have a corresponding reactor channel 132, or the slots 134 may be connected to a single reactor channel. Longer slots may enable multiple substrates or larger substrates to be coated with thin films.

[0058] The modular reactor head 102 can allow for functional flexibility, where individual modular components of different types can be easily added, such as cooling channels, heating channels, plasma sources, and precursor gas modular components having reactor channel openings with unique features (e.g., non-uniform gas delivery to create film gradients, as discussed below). Each modular component can be customized, installed, or replaced for different functions and purposes.

[0059] Figure 4 1 is a side view of the modular reactor head 102. Each modular assembly 114 includes a plurality of slots 136. Each slot 136 is configured to receive a mounting rod (not shown) to support the modular assembly 114 within the modular reactor head 102. In the current embodiment, each slot 136 is larger than the corresponding mounting rod in a direction parallel to the plane 130 to allow the position of each modular assembly 114 to be varied relative to the position of the mounting rod, and thereby allow the position of each modular assembly 114 to be varied along the plane 130. In other words, each modular assembly 114 can be slidably mounted in the modular reactor head 102 to allow the position of each modular assembly 102 along the plane 130 to be adjusted.

[0060] Figure 5A , 5B5C show side views, front views, and isometric views of an embodiment of a modular reactor head 500 having a plurality of modular components 114 with adjustable spacing heights and at different heights. The modular reactor head 500 can be substantially similar to the modular reactor head 102 and can be formed using the same plurality of modular components 114 used to form the modular reactor head 102. In one embodiment, the reactor head 500 can include a first precursor gas component 116, a second precursor gas component 118, an inert gas component 120, an exhaust component 122, and a cooling component 124, however, it should be understood that the modular components can vary, wherein at least two of the modular components are precursor gas components. The height of an individual modular component 114 relative to the substrate and other modular components (and thus the height of the corresponding reactor channel opening) can be precisely mechanically adjusted relative to adjacent modular components 114 to achieve the spacing height between them. For example, the height of each modular component 114 can be adjusted by sliding the modular component 114 relative to the adjacent modular component 114 (perpendicular to the rod axis). Adjustment of the spacing height can provide more flexibility and control over gas flow. exist Figure 5A , 5B 5C, the exhaust assembly 120 is slightly moved upward along plane 130 to create an area into which the precursor gas will naturally flow to improve exhaust efficiency and prevent or reduce the possibility of gas mixing.

[0061] Figure 61 is a perspective view of an embodiment of a modular assembly that can be used as a modular cooling (or heating) assembly 124. In some embodiments of a modular reactor head, a thermal assembly (including a heating and cooling assembly) can be positioned adjacent to a precursor gas assembly. The thermal assembly allows the temperature of at least a portion of the modular reactor head to be controlled. For example, the temperature of the precursor gas assembly adjacent to the thermal assembly can be controlled relative to the temperature of the heated substrate stage to obtain the desired film deposition conditions. In one embodiment, the reactor channel 132 of the modular cooling assembly 124 includes a cooling plate 138 for removing heat from an adjacent precursor gas modular assembly. In one embodiment, the cooling plate is made of a metal such as, but not limited to, copper. In one embodiment, cooling water can be circulated inside the reactor channel 132 of the modular cooling assembly to provide a temperature difference between the modular cooling assembly and the adjacent precursor gas modular assembly. In an alternative embodiment, the cooling water can be replaced with hot water or a heating element to heat the precursor gas opening of the precursor gas modular assembly. More specifically, for the modular cooling assembly, the cooling plate is cooled when the cooling liquid passes through its reactor channel to extract heat from the adjacent modular assembly, thereby ensuring that the chemical reaction occurs on the substrate rather than in the adjacent modular assembly. Alternatively, for modular heating elements, modular assembly cooling plates or heating elements are heated to heat reactor channels adjacent to modular assemblies (such as adjacent to precursor gas modular assemblies) for precursor gases that tend to produce undesirable condensation on cold surfaces.

[0062] Figure 7 is a perspective view of an embodiment of a modular reactor head 700. The modular reactor head 700 can be substantially similar to the modular reactor head 102 and the modular reactor head 500. The modular reactor head 700 can be scaled within a thin film deposition system to increase the thin film deposition area and / or throughput. For example, the scale of the modular reactor head 700 can be increased in direction 126 by using modular components with reactor channel openings having an increased length in direction 126. Increasing the scale of the modular reactor head 700 in direction 126 can increase the size of the film deposited on the substrate in direction 126, and thereby increase the area of ​​the film or the number of substrates deposited. The scale of the modular reactor head 700 can be increased in direction 128 by increasing the number of modular components that form the reactor head 700, for example by adding additional modular components, such as, but not limited to, precursor gas components. Increasing the scale of the modular reactor head 700 in direction 128 can increase the thickness of the film deposited in one pass of the modular reactor head 700, and thereby increase the throughput of the modular reactor head 700.

[0063] Fig. 8A and 8BA front view and a perspective view of an embodiment of a thin film deposition system are shown. The thin film deposition system 800 includes a reactor head positioning system 804. The thin film deposition system 800 can be substantially similar to the thin film deposition system 100. The reactor head positioning system 804 includes a mounting element (not shown) for receiving the reactor head 801, such as the modular reactor head 102, and is configured to adjustably maintain the orientation and position of the reactor head 801 relative to the substrate 806, on which the thin film is deposited. Specifically, the reactor head positioning system 804 is configured to control the distance between the modular reactor head 800 and the substrate 806. In an embodiment of the present invention, the reactor head positioning system 804 includes a linear displacement system, which includes one or more laser displacement sensors 808 used as displacement measuring devices and one or more linear actuators 810 used as displacement control devices. In alternative embodiments, other displacement measuring devices and actuators can be used. In combination with the displacement measuring device and the actuator, software, such as in the form of a module or instruction stored on a computer readable medium, is used to dynamically monitor and adjust the spacing between the reactor head 801 and the substrate 806. In one embodiment, a resolution of 1 micron is used. The ability to accurately control the reactor-substrate spacing (i.e., in plane 130) can provide control over whether the precursor gases are kept isolated (ALD occurs) or mixed in the gas phase (CVD occurs). An example of a conventional positioning system is a floating wafer system, but a floating wafer system is limited to substrates that can float. In other words, the positioning system of an embodiment of the present invention can provide greater flexibility in terms of the size, quantity, or type of substrates that can be used for thin film deposition. In an embodiment of the present invention, the reactor head positioning system 804 is configured to move the reactor head 801 along plane 130 to control the reactor-substrate spacing between the substrate 806 and the reactor head 801, but in an alternative embodiment, the substrate 806 can move along plane 130 while the reactor head 801 remains stationary.

[0064] The deposition system can be equipped with a loading and unloading mechanism for the substrate, such as a robotic arm, to fully automate the manufacturing process. The deposition system can also be compatible with roll-to-roll technology, such as thin film deposition on plastics, fabrics, or foils. For roll-to-roll systems, the substrate can be configured to be compatible with a continuous web of plastic, fabric, or foil, for example, the substrate stage can include rollers to keep a portion of the web near the reactor head at at least an approximately constant distance from the reactor head, and the system can control the position of the web and the number of depositions to achieve a desired thickness on the web by rolling / unrolling the web.

[0065] Fig. 9A is a perspective view of an embodiment of a substrate stage 900 . The substrate stage 900 may be substantially similar to the substrate stage 108 . Fig. 9B900. A cross-sectional view of an embodiment of a substrate stage 900 is shown. In an embodiment of the present invention, the substrate stage 900 includes an upper plate 902 having a plurality of holes 904, a heating assembly 905 (shown in phantom), such as a heating element embedded within the upper plate 902, and a vacuum reservoir 908 fluidly coupled to the plurality of holes 904 to provide suction to the plurality of holes 904. The upper plate 902 may be an upper metal plate.

[0066] The upper plate 902 is separated from the vacuum reservoir 908 by a thermal insulation layer 906, which may be an air gap, to thermally insulate the vacuum reservoir 908 from the upper plate 902, which is heated by the heating element 905. A substrate (not shown) may be placed on the upper plate 902, and when suction is provided, the plurality of holes 904 in the upper plate 902 may securely hold the substrate in place on top of the upper plate 902. In other words, the vacuum reservoir 908 coupled to the plurality of holes 904 in the upper plate 902 forms a mechanism for holding a substrate to the substrate stage 900.

[0067] Fig.10 900. is a perspective view of four (4) substrates 912 held on a substrate stage 900. Substrates of varying sizes, geometries, thicknesses, and materials (e.g., glass, silicon wafers) can be placed on or heated by the upper plate 902 (heated by a heating element) and held by the vacuum holding mechanism 908, provided that the substrates are approximately within the dimensions of the substrate stage and are flat. The plurality of holes 904 can be configured to accommodate substrates 912 of varying sizes and geometries. Caps (not shown) can be added to the plurality of holes 904 as needed to prevent or reduce the likelihood of suction occurring at specific locations on the substrate stage 900.

[0068] In one embodiment, the upper plate 902 is offset from the vacuum reservoir 908 (which provides suction to hold the substrate 912 down) by a predetermined distance, such as about 10 mm or more, to provide an air gap 9 for insulation. As discussed above, insulating material can be added to isolate the vacuum reservoir 908 and the underlying system components from the heat generated by the heating element 905.

[0069] Fig.11 902. is a bottom perspective view of an embodiment of an upper plate 902. In the current embodiment, the upper plate 902 includes a heating assembly, such as a heater 905 embedded within. In alternative embodiments, more than one heating element 905 may be embedded within the upper plate 902, as discussed below. Thermal grease may be used to increase thermal conductivity between the heating element 905 and the upper plate 902. The heating provided by the heating assembly may alternatively be implemented by an infrared heating element or a laser heating element, whereby these heating elements may perform other functions in addition to heating.

[0070] Fig. 12AA top view of an embodiment of a heating element 1200 having a single heating cell 1202 is shown. Fig. 12B A top view of an embodiment of a heating element 1204 is shown, the heating element having three heating units 1202 positioned in three heating zones 1206, 1208 and 1210, whereby the heating element 1204 can be considered to be configured for zone controlled heating. In alternative embodiments, the heating element 1204 can have two, four or more heating units, and thus two, four or more corresponding heating zones can be controlled individually. Depending on the selection and placement of the heating element, the heating element can be configured for uniform or non-uniform heating. This modular heating element design helps to improve energy usage for different substrate geometries, achieve uniform heating and non-uniform zone heating of substrates, and achieve rapid prototyping by allowing deposition on multiple substrates at different temperatures. In addition, non-uniform / regional heating can be used to determine the operating temperature range of the ALD mode and the CVD mode of different chemicals. In alternative embodiments, gradient heating can be used. The heating element 1200 and the heating element 1204 can be substantially similar to the heating element 905.

[0071] Fig.13A is a schematic diagram of a reactor head 1300 having a modular assembly 1301, wherein a reactor channel 1302 is configured to deliver a uniform flow distribution, as indicated by the arrows below the reactor channel. Conventional ALD techniques typically deposit thin films having uniform thickness and composition, which can be achieved by delivering a precursor gas having a uniform flow distribution. The thin layer deposition system of the present disclosure is capable of depositing uniform films as well as films having non-uniform thickness and composition. The geometry of the reactor channels in the precursor gas modular assembly in the modular reactor head can be modified to control the flow distribution of the gas through the precursor gas or reactor channel openings so that different amounts of precursor gas can be delivered to different locations on the substrate.

[0072] Fig. 13B 1304 is a schematic diagram of a reactor head 1304 having modular assemblies, wherein at least one of the modular assemblies has a reactor channel 1306, wherein the reactor channel is configured to deliver a non-uniform flow distribution, as shown by the arrows below the reactor channel 1306, wherein the fluid flows faster at one end where the arrows are closer than at the other end where the arrows are farther apart. The non-uniform flow distribution enables more material to be deposited at locations where more precursor gas is delivered. Depending on the flow distribution of the fluid, gas or liquid, linear, non-linear or complex thickness or composition changes can be generated across the membrane. In one embodiment, a specific flow distribution of a precursor gas modular assembly can be obtained by designing the geometry of the reactor channel or precursor gas, slit or opening using computational fluid dynamics (CFD) simulations. Fig.13A and13B We show how to tailor the precursor gas reactor channel openings to produce uniform precursor gas flow and thus films of uniform thickness and composition. Fig.13A ) or non-uniform precursor gas flow and thus films with thickness and / or composition gradients ( Fig. 13B ).

[0073] Fig.14A A schematic geometry or portion of a reactor channel 1400 for delivering a non-uniform flow distribution when used in a modular assembly such as modular assembly 114 is shown. In the current embodiment, the reactor channel 1400 includes a fluid inlet portion 1410, which includes an inlet region 1412 for receiving a fluid. When the fluid passes through the inlet region 1412, it leaves the inlet region (through an exit point 1413) and flows downward toward the reactor channel opening 1414. When the fluid leaves the inlet region 1412, the velocity of the fluid flowing out of or moving out of the reactor channel opening 1414 closer to the exit point 1413 (see region 1414a) is higher than the velocity of the fluid flowing out of or moving out of the reactor channel opening 1414 farther from the exit point (see region 1414b).

[0074] Fig. 14B Shown by having Fig.14A Computational fluid dynamics (CFD) simulation of the flow of the reactor channel opening of the modular assembly of the reactor channel geometry shown in . In the current embodiment, one end of the reactor channel opening delivers more precursor gas at a higher outlet velocity than the opposite end of the reactor channel opening. When the reactor channel 1400 is used for a modular reactor head of CVD, this may cause the precursor gas to mix more at one end of the precursor gas slit or opening, thereby producing a non-uniform deposition rate along the length of the precursor gas slit. Alternatively, if the reactor channel 1400 is used for a modular reactor head of AP-SALD, at one end of the reactor channel opening, during each ALD cycle, the substrate may be completely saturated with the precursor, while at the other end of the reactor channel opening, the substrate may not be completely saturated, which again produces a non-uniform deposition rate along the length of the reactor channel opening. The geometry of the reactor channel opening can be varied for one or more reactor channel openings, producing a non-uniform deposition rate of one or more components of the film. If all film components have the same non-uniform deposition rate, a film with non-uniform thickness in the first direction will be produced. In other words, the thickness of the film can be different. If film components having uniform and non-uniform deposition rates (or different non-uniform deposition rates) are deposited simultaneously, the resulting film will have a non-uniform composition.

[0075] Fig. 14C is a schematic diagram of a reactor head 1402 with a non-uniform flow distribution. Fig.14DIt is a photo of the 3D printing of reactor head 1402. In an embodiment of the present invention, all precursor gas reactor channel openings, inert gas reactor channel openings and exhaust reactor channel openings (or precursor gas modular components, inert gas modular components and exhaust modular components) are incorporated into a single reactor head assembly for small-scale testing. In an alternative embodiment, the reactor head can include multiple modular components with non-uniform flow distribution. For the current embodiment, reactor head 1402 is used to deliver diethyl zinc with non-uniform flow distribution and water with uniform flow distribution to the surface of the substrate, and on the surface of the substrate, diethyl zinc and water react to form zinc oxide (ZnO). Use chemical vapor deposition (CVD) conditions so that more diethyl zinc is delivered to one side of the substrate to produce a higher deposition rate and non-uniform film thickness. Fig.15 is a photograph of an example of a zinc oxide film with a thickness gradient produced using reactor head 1402 and deposited using different precursor gas flow rates. The film thickness gradient can be clearly seen from the bands 1404 that form the interference pattern. Fig.16A Shown for Fig.15 Measurement results of film thickness of thickness gradient films across substrates. Fig. 16B A graph of film thickness on the surface of the same substrate is shown. Reactor head 1402 can be used to simultaneously deliver another film component with a uniform flow profile, thereby producing a film with a composition gradient in a first direction. A non-exclusive example of another film component is trimethylaluminum, which can react with water to form aluminum oxide, in which case the amount of zinc in the resulting aluminum-zinc-oxide alloy film will vary across the film or substrate.

[0076] Fig.17A is a schematic diagram of an embodiment of a modular assembly 1700 comprising two symmetrical halves 1702 and 1704 . Fig. 17BShown is a perspective exploded view of a modular assembly 1700. Each half 1702 and 1704 has a release portion 1706 with uniform depth, wherein each release portion 1706 of each half 1702 and 1704 is positioned to form a reactor channel when two half 1702 and 1704 are combined. Two symmetrical half pieces 1702 and 1704 can be used to simplify the design for manufacturing modular assemblies by using additive manufacturing or machining, and can manufacture modular assemblies with non-uniform flow distribution at low cost. Two symmetrical half pieces 1702 and 1704 can be combined to form a modular assembly 1700, and the modular assembly has a reactor channel with uniform width to deliver uniform flow distribution. Alternatively, the depth of each release portion 1706 can be modified by additive manufacturing or machining to provide non-uniform depth (or other profiles) for each release portion 1706, so that when two half parts 1702 and 1704 are combined, a reactor channel with non-uniform flow is formed. With this fabrication technique, combined with modular reactor head technology, each individual reactor head component can be easily customized, installed or replaced for different functions and purposes - for example, being able to deposit films with thickness or composition gradients for rapid prototyping or different functionalities.

[0077] Although not required in every embodiment, the film or thin layer deposition system of the present disclosure may include a substrate positioning system that controls the position of a substrate held by a substrate stage relative to a modular reactor head. For example, the substrate positioning system may be a linear motor positioning system that oscillates a substrate held by a substrate stage and thereby enables high throughput and high precision deposition. A linear motor-based substrate positioning system can maintain the top surface of the substrate at a uniform height during movement, which, when combined with a reactor positioning system, enables precise control of the space between the modular reactor head and the substrate.

[0078] Fig.18 1 is a perspective view of an embodiment of a substrate stage 1800 mounted on a linear motor system 1801, which is positioned on top of a weight such as a granite plate 1802 to vibrate the substrate stage 1800 and the substrate under the modular reactor head. The substrate stage 1800 and substrate can be substantially similar to the substrate stage 108 and substrate 106. In a specific embodiment, the substrate stage 1800, including an upper plate 1808 and a vacuum reservoir 1810, is connected to the linear motor system 1801, which is mounted on a polished granite plate to absorb vibrations caused by the movement of the moving stage. In an alternative embodiment, the linear motor system 1801 can be mounted on a surface with a large mass and a high degree of flatness.

[0079] The linear motor positioning system 1801 can also achieve non-uniform film deposition by oscillating the substrate stage 1800 and the substrate with varying travel distances. The oscillation method allows this technique to vary the substrate oscillation direction ( Figure 2 In other words, by changing the travel distance during oscillation, at least one of the thickness and composition of the film can be changed in this direction.

[0080] In general, the thin film deposition system of the present disclosure can deposit films in which composition or thickness gradients can be generated across the width of the film using precursor gas reactor channel openings with customized geometry. By changing the travel pattern of the heated substrate stage, different thickness or composition gradients can be generated across the width of the film.

[0081] Fig.19 A flow chart of a method 1900 for depositing thin films with a modular reactor head is shown.

[0082] At 1902, a substrate is loaded onto a substrate stage. The substrate stage may be part of a thin film deposition system. The substrate stage may include a vacuum reservoir and a plurality of holes. At 1904, the substrate is secured to the substrate stage by suction from the vacuum reservoir. Suction may be provided to the substrate through the plurality of holes.

[0083] At 1906, a gap between the modular reactor head and the substrate is adjusted using a reactor head positioning system. The reactor head positioning system can be part of a thin film deposition system. Adjusting the gap includes controlling a distance between the modular reactor head and the substrate.

[0084] At 1908, a plurality of precursors including precursor gases are simultaneously and continuously delivered to the modular reactor head. The plurality of precursor gases pass through the modular reactor head by passing through respective reactor channels and exiting respective reactor channel openings toward the substrate. The location at which each precursor gas contacts the substrate is determined by the location of each respective precursor gas modular assembly within the modular reactor head.

[0085] At 1910, the substrate is oscillated under the modular reactor head and material is deposited onto the substrate by the modular components and thereby forms a film. The substrate may be oscillated with a substrate positioning system. The substrate positioning system may be part of a thin film deposition system.

[0086] At 1912, if the thickness of the deposited film is not sufficient, the method returns to 1910. If the thickness of the film is sufficient, then at 1914 the substrate is removed from the substrate stage.

[0087] Fig. 20 A flow chart of a roll-to-roll method 2000 for depositing thin films with a modular reactor head is shown.

[0088] At 2002, a continuous substrate web wrapped around a first roller is loaded onto the first roller and coupled to a second roller mounted on the second roller.

[0089] At 2004, the tension of the substrate between the first roller and the second roller is automatically adjusted. At 2006, the temperature of the substrate is adjusted. The temperature adjustment may include heating the substrate.

[0090] At 2008, a gap between the modular reactor head and the substrate is adjusted using a reactor head positioning system. The reactor head positioning system can be part of a thin film deposition system. Adjusting the gap includes controlling a distance between the modular reactor head and the substrate.

[0091] At 2010, a plurality of precursors including precursor gases are simultaneously and continuously delivered to the modular reactor head. The plurality of precursor gases pass through the modular reactor head by passing through respective reactor channels and exiting respective reactor channel openings toward the substrate. The location at which each precursor gas contacts the substrate is determined by the location of each respective precursor gas modular assembly within the modular reactor head.

[0092] At 2012, the substrate is wound under the modular reactor head and material (such as precursor gas) is deposited on the substrate and thereby forms a film. If the substrate is wound around a first roll, the substrate may be wound under the modular reactor head by winding the substrate from the first roll to a second roll. If the substrate is wound around a second roll, the substrate may be wound under the modular reactor head by winding the substrate from the second roll to the first roll.

[0093] At 2014, if the thickness of the deposited film is not sufficient, the method returns to 2012. If the thickness of the film is sufficient, then at 2016 the web of substrate is unloaded.

[0094] In some embodiments, the present disclosure may be directed to a modular reactor head that can be equipped with different components (heating channels, cooling channels, plasma sources, etc.) and whose components can be arranged and positioned in a variety of configurations, such as but not limited to a reactor head with modular components and adjustable position and height of each component that provides the ability to control gas flow and switch between ALD and CVD system configurations; cooling / heating channels for controlling the temperature of adjacent precursor gas slits to obtain desired thin film deposition conditions; a plasma source; and / or an expandable reactor slit that can increase the throughput of deposition.

[0095] In another embodiment, the present disclosure may be directed to a system for positioning a reactor head relative to a substrate. The reactor head may be modular or non-modular. The system may further control the spacing between the reactor head and the substrate, and thus allow switching between ALD and CVD modes.

[0096] In another embodiment, the present disclosure may be directed to a heated substrate stage with suction and / or local temperature control. In one embodiment, the heated substrate stage may include a vacuum holding mechanism capable of holding any substrate geometry and thickness. In another embodiment, the heated substrate stage may include thermal isolation of the heated substrate stage from other system components.

[0097] In another embodiment, the present disclosure may be directed to a customizable precursor gas slit design that can produce uniform or non-uniform flow distribution from the slit, enabling deposition of films with non-uniform thickness and / or composition perpendicular to the substrate motion.

[0098] In further embodiments, the present disclosure may be directed to a linear motor positioning system that oscillates a substrate relative to a modular reactor head, a) dampens vibrations and maintains the substrate at a uniform height during substrate oscillation to allow precise control of the spacing between the substrate and the modular reactor head; and / or b) enables deposition of films having non-uniform thickness and / or composition in the direction of substrate motion. This may be combined with a customizable precursor gas slit design to produce films having different thickness and composition gradients in orthogonal directions.

[0099] In yet further embodiments, the present disclosure may be directed to a plurality of deposition systems that may be equipped with roll-to-roll technology and / or substrate loading and unloading mechanisms for high throughput production.

[0100] In another embodiment, the present disclosure can be directed to depositing thin layers of material on fabrics with modular reactor heads, such as ALD deposition of copper oxide onto nonwoven fabrics for N95 masks. Conventional spraying or wet coating of copper oxide onto fabrics typically fills the pores of the fabric, which can affect the performance of the mask, whereas CVD and / or ALD of copper oxide can provide an antiviral coating for the mask with a reduced impact on mask performance compared to conventional coating techniques.

[0101] Although the disclosure has been illustrated and described herein with reference to preferred embodiments and specific examples thereof, it will be apparent to those skilled in the art that other embodiments and examples may perform similar functions and / or achieve similar results. All such equivalent embodiments and examples are within the spirit and scope of the disclosure.

[0102] In the foregoing description, for the purpose of explanation, many details are set forth in order to provide a thorough understanding of the embodiments. However, it should be apparent to those skilled in the art that these specific details may not be required. In other cases, well-known structures may be shown in block diagram form to avoid confusion. For example, no specific details are provided regarding whether the elements of the embodiments described herein are implemented as software routines, hardware circuits, firmware, or a combination thereof.

Claims

1. A modular reactor head for use with a thin film deposition system, the modular reactor head comprising: a set of modular assemblies adjacent to each other in a first direction within the reactor head; wherein the set of modular components comprises at least two precursor gas modular components for depositing at least two precursor gases onto a substrate, the at least two precursor gas modular components being separated by at least one other modular component, the at least one other modular component comprising at least one of: a precursor fluid modular component, an exhaust modular component, an inert gas modular component, a temperature control modular component, a cleaning modular component, and a plasma source modular component, The temperature control modular component includes: a metal plate, which is used to control the temperature of modular components adjacent to the temperature control modular component; and a reactor channel for receiving cooling liquid to cool the metal plate or receiving heating liquid to heat the metal plate.

2. The modular reactor head of claim 1, wherein at least one modular component of the set of modular components comprises: Reactor channel; as well as Reactor channel opening.

3. A modular reactor head according to claim 2, wherein the reactor channel opening delivers gas or liquid material at a higher exit velocity at one end of the reactor channel opening than at an opposite end of the reactor channel opening.

4. A modular reactor head according to claim 1, wherein the set of modular components are mounted at a predetermined height relative to each other.

5. The modular reactor head of claim 1, wherein the precursor fluid modular assembly comprises an actuator for controlling the deposition of the precursor fluid.

6. A thin film deposition system, comprising: A substrate stage, the substrate stage is used to support a substrate; a modular reactor head for depositing a thin film onto the substrate, the modular reactor head comprising a set of modular components adjacent to each other in a first direction within the reactor head; wherein the set of modular components comprises at least two precursor gas modular components for depositing at least two precursor gases onto a substrate, the at least two precursor gas modular components being separated by at least one other modular component, the at least one other modular component comprising at least one of: a precursor fluid component, an exhaust modular component, an inert gas modular component, a temperature control modular component, a cleaning modular component, and a plasma source modular component; as well as a modular reactor head position system for positioning the modular reactor head relative to the substrate on the substrate stage, The temperature control modular component includes: a metal plate, which is used to control the temperature of modular components adjacent to the temperature control modular component; and a reactor channel for receiving cooling liquid to cool the metal plate or receiving heating liquid to heat the metal plate.

7. The thin film deposition system of claim 6, wherein the modular reactor head position system comprises a linear displacement system.

8. The thin film deposition system according to claim 7, wherein the linear displacement system comprises: A set of displacement measuring devices; as well as A set of linear actuators.

9. The thin film deposition system of claim 6, wherein the modular reactor head position system comprises: A leveling system for gap control between the modular reactor head and the substrate table.

10. The thin film deposition system according to claim 6, wherein the substrate stage comprises: A vacuum system is provided for holding the substrate against the substrate stage.

11. The thin film deposition system according to claim 6, wherein the substrate stage comprises: an upper plate for supporting the substrate; as well as A heating assembly is used to heat the upper plate.

12. The thin film deposition system of claim 6, wherein the substrate stage comprises a linear motor system.

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