Material deposition apparatus, method for depositing material on a substrate, and material deposition system - Patents.com

Abstract

A material deposition apparatus for depositing evaporated material on a substrate is provided, the material deposition apparatus including a process drum having a cooler configured to control a substrate temperature during processing of the substrate on the process drum, rollers for guiding the substrate towards the process drum, a first heater assembly arranged to heat the substrate in a free span area between the rollers and the process drum, a second heater assembly arranged to heat the substrate while supported on the process drum, at least one deposition source disposed along a substrate transport path downstream of the second heater assembly, a substrate velocity sensor providing a velocity signal correlating to a substrate transport speed, and a controller having an input for the velocity signal configured to control at least the first heater assembly.

Description

[Technical field]

[0001] The embodiments of the present disclosure relate in particular to substrate coating by thermal evaporation in a vacuum chamber. The embodiments of the present disclosure further relate to material deposition of evaporated material onto a substrate, in particular for the manufacture of batteries. The embodiments of the present disclosure relate to one or more heating assemblies for a material deposition apparatus for preheating a substrate, a method for depositing material onto a substrate, and a material deposition system. [Background technology]

[0002] Various techniques for deposition onto a substrate are known, such as chemical vapor deposition (CVD) and physical vapor deposition (PVD). For deposition at high deposition rates, thermal evaporation can be used as a PVD process. In thermal evaporation, a source material is heated to generate a vapor that can be deposited onto the substrate. Increasing the temperature of the heated source material can increase the vapor concentration and promote high deposition rates. The temperature to achieve high deposition rates depends on the physical properties of the source material, such as the vapor pressure as a function of temperature, and the physical limitations of the substrate, such as the melting point.

[0003] Deposition of metals, such as lithium, on flexible substrates, such as graphite foils or copper substrates, by evaporation can be used for the manufacture of batteries, such as Li batteries. For example, a lithium layer can be deposited on a thin flexible substrate to manufacture the anode of a battery. After assembly of the anode layer stack and the cathode layer stack, optionally with an electrolyte and / or separator between them, the manufactured layer configuration can be rolled or otherwise stacked to manufacture a Li battery.

[0004] Thermal expansion during substrate processing can cause wrinkles in the substrate, e.g., foil or web. Spreading of the foil, especially rapid spreading of the foil, can result in wrinkles on the foil. The wrinkles can cause a reduction in the quality of one or more deposited layers.

[0005] It would therefore be beneficial to provide an improved material deposition apparatus, an improved deposition method, and an improved processing system to at least partially overcome the above-mentioned problems. Summary of the Invention

[0006] In light of the above, a material deposition apparatus, a method for depositing a material on a substrate, and a material deposition system are provided as set forth in the independent claims. Further features, aspects, details and implementations are set forth in the detailed description, the drawings and the dependent claims.

[0007] According to one embodiment, a material deposition apparatus for depositing evaporated material on a substrate is provided, the material deposition apparatus comprising: a processing drum having a cooler configured to control a substrate temperature during processing of the substrate on the processing drum, rollers for guiding the substrate towards the processing drum, a first heater assembly arranged to heat the substrate in a free-span area between the rollers and the processing drum, a second heater assembly arranged to heat the substrate while supported on the processing drum, at least one deposition source disposed along a substrate transport path downstream of the second heater assembly, a substrate velocity sensor providing a velocity signal correlating to a substrate transport speed, and a controller having an input for the velocity signal configured to control at least the first heater assembly.

[0008] According to one embodiment, a method of depositing evaporated material on a substrate is provided, the method including guiding the substrate from a roller towards a processing drum, measuring a substrate velocity signal, and heating the substrate between the roller and the processing drum with a first heater assembly in response to the substrate velocity signal.

[0009] According to one embodiment, a material deposition system is provided that includes a processing drum for supporting a substrate during processing, a substrate guide roller upstream of the processing drum, a first heater assembly disposed between the roller and the processing drum, and a controller having a processor and a memory storing instructions that, when executed by the processor, cause the controller to perform a method according to an embodiment of the invention.

[0010] So that the above-recited features of the present disclosure can be understood in detail, a more particular description of the present disclosure briefly summarized above can be had by reference to the embodiments. The accompanying drawings relate to embodiments of the present disclosure and are described below. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic diagram of a material deposition apparatus according to embodiments described herein. [Diagram 2] FIG. 2 is a schematic diagram of a controller for a heater in a deposition system according to embodiments described herein. [Diagram 3] 1 is a flow diagram of a method according to an embodiment described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Reference will now be made in detail to various embodiments of the present disclosure, one or more examples of which are illustrated in the figures. In the following description of the drawings, like reference numerals refer to like components. Generally, only the differences with respect to individual embodiments will be described. Each example is given as an explanation of the disclosure, and not as a limitation of the disclosure. Furthermore, features illustrated or described as part of one embodiment can also be used in other embodiments or with other embodiments to yield further embodiments. It is intended that the description include such modifications and variations.

[0013] The embodiments provided herein relate to thin film coating by evaporation, particularly thin film coating in a vacuum chamber. For example, the material to be coated is heated to a material-specific temperature so that it is evaporated. Generally, higher temperatures can provide higher evaporation rates.

[0014] The embodiments of the present disclosure reduce the spreading of the substrate, i.e., flexible substrate, such as a foil or web, due to heat. Wrinkling can be reduced to enhance the quality of thin film deposition on the substrate. According to the embodiments of the present disclosure, one or more temperature control zones are provided. In particular, a first temperature control zone, such as a low power control zone, is provided. In the first temperature control zone, velocity-dependent heating of the substrate is provided. According to some embodiments, which can be combined with other embodiments described herein, velocity-dependent pre-heating of the substrate, e.g., graphite foil, can be provided before the substrate contacts the processing drum. The first temperature control zone can be provided in a free span area. The free span area can be a substrate guiding area between a roller adjacent to the processing drum and the processing drum.

[0015] According to one embodiment of the present disclosure, a material deposition apparatus for depositing evaporated material on a substrate is provided, the material deposition apparatus includes a processing drum having a cooler configured to control a substrate temperature during processing of the substrate on the processing drum, a roller for guiding the substrate towards the processing drum, a first heater assembly arranged to heat the substrate in a free span area between the roller and the processing drum, a second heater assembly arranged to heat the substrate while supported on the processing drum, at least one deposition source disposed along a substrate transport path downstream of the second heater assembly, a substrate velocity sensor providing a velocity signal correlating to a substrate transport velocity, and a controller having an input for the velocity signal configured to control at least the first heater assembly.

[0016] Furthermore, in evaporation systems and material deposition apparatuses including evaporators, the evaporated material condenses on the surfaces of system components that have a lower temperature than the evaporated material. In the case of thermal coating of a substrate, the substrate includes a lower temperature so that the evaporated material can be deposited or coated onto the substrate to form a thin layer on the substrate. However, if the difference between the temperature of the substrate and the temperature of the material to be coated is large, the resulting thin layer or film may be damaged, for example, cracked, or wrinkled on the surface of the substrate and / or material.

[0017] 1 exemplarily illustrates a material deposition apparatus according to an embodiment described herein, which may be combined with any other embodiment described herein. The material deposition apparatus 100 may include a vacuum chamber 105. A vacuum may be provided in the vacuum chamber. For example, the material deposition apparatus may include a vacuum pump for providing a vacuum in the vacuum chamber.

[0018] The term "vacuum" as used herein can be understood in the sense of a technical vacuum, for example having a vacuum pressure of less than 10 mbar. In general, the pressure in the vacuum chambers described herein is less than 10 -4 mbar and about 10 -8 Between mbar and, more commonly, 10 -4 mbar and 10 -7 Between mbar and, more commonly, about 10 -5 mbar and about 10 -6 In some embodiments, the total pressure in the vacuum chamber or chambers can be between about 10 -4 mbar to about 10 -7 The vacuum chamber may thus be a "vacuum deposition chamber", i.e. a vacuum chamber configured for vacuum deposition.

[0019] According to an embodiment that can be combined with any other embodiment described herein, the material deposition apparatus can include a deposition source assembly. For example, the deposition source assembly can be an evaporation source assembly that includes one or more evaporation sources. The embodiments of the present disclosure relate to deposition sources, particularly physical vapor deposition (PVD) sources, in which energy is transferred to the substrate by a deposition process. For high deposition rates, evaporation sources can be particularly useful. Therefore, the following description refers to evaporation sources. It should be understood that other deposition sources, particularly deposition sources that transfer energy to the substrate, can also be utilized for the embodiments of the present disclosure.

[0020] The term "evaporation source assembly" as used throughout this disclosure may be understood as an assembly, unit or device that includes one or more evaporation sources. Thus, features described herein with respect to an evaporation source assembly may also apply correspondingly to a single evaporation source. For example, only one evaporation source may be included in the evaporation source assembly. In such cases, the evaporation source assembly may be referred to as an evaporation source. According to some embodiments, which may be combined with other embodiments described herein, two or more evaporation sources may be provided in the evaporation source assembly.

[0021] The evaporation source assembly is configured to provide evaporated material towards the substrate 102. The evaporation source assembly can be provided in the vacuum chamber 105 or at least partially in the vacuum chamber 105. The evaporation source assembly can be disposed along a substrate transport direction (D) for providing material to the substrate.

[0022] An evaporation source assembly can include two or more evaporation sources. Two evaporation sources 110 are shown in Figure 1. For example, an evaporation source assembly can include a first evaporation source having a first deposition area for depositing material on a substrate and a second evaporation source having a second deposition area for depositing material on a substrate.

[0023] According to an embodiment, which may be combined with any other embodiment described herein, the material deposition apparatus may include a processing drum 120. The processing drum may be configured to transport the substrate 102. The substrate 102 may be configured around the processing drum 120. The processing drum 120 may be a coating drum, exemplarily shown in FIG. 1. The coating drum may include a curved drum surface. The processing drum may be configured to move the substrate 102 on the curved drum surface in a circumferential or substrate transport direction past the evaporation source 110.

[0024] According to an embodiment that can be combined with any other embodiment described herein, the evaporation source assembly can provide the material to be deposited on the substrate. The evaporation source assembly can include one or more crucibles in which the material to be deposited can be evaporated by providing the material with a suitable temperature to evaporate the material. For example, the material to be deposited can include, for example, metals, in particular lithium, metal alloys, and other vaporizable materials having a gas phase under given conditions. According to yet a further embodiment, in addition or alternatively, the material can include magnesium (Mg), ytterbium (Yb), and lithium fluoride (LiF).

[0025] Further, the evaporation source of the evaporation source assembly may include a distributor. The distributor may distribute the evaporated material. The material may be provided in the distributor, for example, by a crucible connected to the distributor through an inlet opening. The distributor may have one or more openings. The evaporated material to be deposited may exit the distributor through the openings. The source material may be deposited on the substrate 102 by multiple nozzles extending through the openings. In other words, the evaporation source may include one or more nozzles for providing the evaporated material to the substrate. The material to be deposited may be sprayed onto the substrate, for example, by multiple nozzles.

[0026] For example, the substrate may be a flexible web or foil and the material deposition apparatus may be a roll-to-roll deposition apparatus. The coating drum may be a cylinder extending in a length direction perpendicular to the plane of the paper in FIG. 1. The treatment drum may be movable, i.e., the coating drum may be rotated about a central axis. The treatment drum may be moved or rotated clockwise or counterclockwise. The treatment drum may change direction during deposition, e.g., when the treatment drum is rotated clockwise during deposition, the direction of rotation may be changed to counterclockwise and vice versa.

[0027] According to an embodiment that can be combined with any other embodiment described herein, the material deposition apparatus may include a substrate provision or unwind roll (not shown in FIG. 1) for providing an unprocessed substrate. The substrate provision or unwind roll may be moved, i.e., rotated, so that the substrate may be unwound from the substrate provision or unwind roll. In addition, the material deposition apparatus may include a substrate receiving roll for picking up the processed substrate after deposition of the material onto the substrate has been performed. The substrate receiving roll may be moved, i.e., the substrate receiving roll may be rotated to pick up the processed substrate. The substrate receiving roll and the substrate provision or unwind roll may be rotated in the same direction, i.e., both rolls may be rotated clockwise, or the substrate provision or unwind roll may be rotated in the opposite direction, i.e., one roll may be rotated clockwise and the other roll may be rotated counterclockwise, or vice versa. For example, the substrate may be "spanned" between the unwind roll and the receiving roll and guided above the evaporation source assembly to receive the evaporated material. For example, the substrate may be provided with a defined and / or controlled force. A board tensioner may be provided.

[0028] According to some embodiments, which can be combined with other embodiments described herein, the treatment drum can be a gas cushion treatment drum. The gas cushion coating drum provides a cooling gas between the surface of the drum and the substrate. For example, the drum and the cooling gas can be cooled to a temperature below room temperature. Heat can be removed from the substrate to allow for higher deposition rates without damaging the thin foil or web on which the material is deposited.

[0029] In the case of the gas cushion roller, a first subgroup of gas outlets, i.e. open gas outlets, can be provided in the web guiding area of ​​the processing drum. A second subgroup of gas outlets, i.e. closed gas outlets, is provided outside the web guiding area. Since gas is only released into the web guiding area where it is needed to form the hover cushion, no or very little gas is released directly into areas not covered by the web, gas waste can be reduced and / or a better vacuum can be maintained with less strain on the pump system.

[0030] According to some embodiments, which can be combined with other embodiments described herein, in addition to or as an alternative to a subgroup of gas outlets, the outer surface of the processing drum can be coated with a microporous surface. The microporous surface can allow a small amount of cooling gas to flow from the inside of the processing drum to the surface of the processing drum. The cooling gas can form a gas cushion between the processing drum and a web or foil that is guided over the processing drum for material deposition thereon.

[0031] According to embodiments that can be combined with any other embodiment described herein, the substrate can be a thin substrate, for example a foil or web. The substrate to be coated can have a thickness of 50 μm or less, in particular 20 μm or less, or even 10 μm or less. For example, a metal foil or a flexible metal-coated foil can be coated in a vapor deposition apparatus. In some implementations, the substrate 102 is a graphite foil or a copper foil or a thin aluminum foil with a thickness of less than 30 μm, for example 10 μm or less. According to some embodiments that can be combined with other embodiments described herein, the metal foil, such as a Cu foil or an Al foil, can have a thickness of 5 μm to 20 μm. The graphite foil can include a metal foil with a graphite coating, a graphite silicon coating, or an almost pure Si coating, for example as described above, on at least one side, in particular on both sides. The coating can be, for example, 20 μm to 50 μm.

[0032] When the thickness of the substrate is small, the substrate will experience rapid temperature changes in different zones with different thermal loads, i.e., the substrate heats up quickly, the substrate expands, and cools down quickly, the substrate contracts. Such rapid temperature changes create tensions, stresses and stretches in the substrate, which can cause damage and / or wrinkling.

[0033] FIG. 1 shows a material deposition apparatus 100 or a corresponding processing system. The material deposition apparatus 100 includes a vacuum chamber 105. In the vacuum chamber 105, a processing drum 120 is provided. A substrate 102, for example a flexible web or a foil, such as a graphite foil, is guided onto the processing drum 120 for processing the substrate 102. The substrate 102 is guided along a substrate transport direction D over rollers 125. The rollers guide the substrate towards the processing drum 120. The substrate is processed on the processing drum 120. For example, one or more evaporation sources 110 can be provided along the substrate guide path on the processing drum 120. FIG. 1 shows two evaporation sources 110. The evaporation sources can deposit a material on the substrate. According to an embodiment of the present disclosure, in particular a lithium-containing film can be deposited on the substrate, such as a graphite substrate.

[0034] Uncontrolled temperature changes in the substrate can result in wrinkles that degrade the thin film deposited on the substrate. According to an embodiment of the present disclosure, a heater is provided in a dedicated heating zone to control the substrate temperature to reduce the occurrence of wrinkles on the substrate.

[0035] A first heater assembly 140 is provided that includes one or more first heaters 142. The first heater assembly provides a first heating zone. The first heating zone or first heater assembly, respectively, is provided in a free span area of ​​the substrate 102 between the roller 125 and the processing drum 120. Each first heater of the first heater assembly is connected to the controller 130 by a control line 132.

[0036] A second heater assembly 160 is provided, including one or more second heaters 162. The second heater assembly provides a second heating zone, for example a transition heating zone between the first heating zone and the third heating zone. The third heating zone can be provided by a third heater assembly 170, including one or more third heaters 172. The third heating zone can be a high power heating zone. The high power heating zone is adjacent to one or more evaporation sources 110. Furthermore, according to some embodiments, which can be combined with other embodiments described herein, a roller heater 131 can be provided. The roller heater is configured to heat a surface of the roller. The substrate is heated by the roller heater while being guided by the roller 125.

[0037] The term "heater assembly" as used throughout this disclosure may be understood as an assembly, unit, or device that may include one or more heaters. For example, a heating assembly may include at least one heater, or may include two or even more heaters.

[0038] A "heater" as used throughout this disclosure may be a graphite heater. Graphite heaters are advantageous because they provide high operating temperatures, e.g., in the range of 500° C. to 1800° C. or higher, and high emissivity, e.g., in the range of 0.8 to 0.9 or higher, which allows for high power density on the substrate. The heating element may also include a radiation shield to focus the power in a direction toward the substrate. According to some embodiments, which may be combined with other embodiments described herein, the heater may include or be a light source. The wavelength of the light source may range from infrared (IR) to ultraviolet (UV), depending on the particular substrate to be heated. Some substrate materials may be UV sensitive. Other substrate materials may be IR sensitive.

[0039] According to an embodiment of the present disclosure, a plurality of temperature sensors 152 are provided. The temperature sensors 152 are distributed along the substrate transport path. In particular, the temperature sensors can be correlated with the start of a heating zone. Additionally or alternatively, the temperature sensors can be correlated with the end of a heating zone. The temperature sensors can be thermocouples or pyrometers, i.e., temperature sensors that measure the thermal radiation of the substrate. The temperature sensors 152 can be connected to the controller 130 by signal lines 134. The signal lines 134 provide a temperature signal to the controller 130. For example, one or more transition temperature sensors can be provided during a transition heating zone where temperature-dependent substrate heating is provided.

[0040] The embodiments of the present disclosure provide heating zones with specific temperature control characteristics. In particular, the first heating zone provided between rollers 125 in the processing drum 120 is a velocity dependent heating zone. A substrate velocity sensor, which may be provided on the processing drum 120 or on the rollers 125, provides a velocity signal via signal line 122. Signal line 122 is shown on the processing drum 120 in FIG. 1 . However, signal line 122 may also be provided on the rollers 125 or at another location in the material deposition apparatus 100. For example, the substrate velocity may be provided on the unwind spool of the material deposition system, on the wind spool of the material deposition, or at another location in the material deposition system.

[0041] The third heating zone or high power heating zone can be provided with constant heating, i.e. constant power mode, or with heating according to the evaporation rate. In particular, the temperature control in the third heating zone is independent of the substrate speed, and the substrate temperature can also be controlled in the stationary state of the substrate while it is being provided on the processing drum 120. According to some embodiments, which can be combined with other embodiments described herein, the third heating zone can be controlled according to the evaporation rate, i.e. the energy provided by the evaporation source towards the substrate. A third heater 172 is provided adjacent to the evaporation source 110, for example upstream of the evaporation source, between the evaporation sources and / or downstream of the evaporation source, to provide the same heating to the substrate compared to the evaporation source, thereby reducing or avoiding sudden temperature changes of the substrate during material deposition.

[0042] A second or transition heating zone is provided between the first and third heating zones. The second heating zone can be provided shortly before the substrate contacts the processing drum, e.g., a cooled gas cushion drum. The second heating zone is a temperature-dependent heating zone with temperature control depending on the substrate temperature after the first heating zone. Furthermore, the temperature control in the second heating zone can be made dependent on the temperature in the third heating zone. For example, FIG. 1 shows two temperature sensors between the first and second heating zones for improved temperature control after the rate-dependent first temperature zone.

[0043] According to some embodiments, which can be combined with other embodiments described herein, the temperature control of the substrate in the free span area between the roller 125 and the processing drum 120 can be provided by a first temperature zone with speed-dependent control and partly by a second temperature zone with temperature-dependent control. The speed-dependent control in the first heating zone allows a continuous increase of the substrate temperature between the roller 125 and the second heating zone. The second heating zone raises the temperature in the deposition area to the final temperature. In particular, the substrate temperature is raised to the final deposition temperature before the substrate contacts the processing drum. The second heating zone is temperature-dependent. The second heating zone, i.e. the transition heating zone, can be provided partly in the free span zone and partly on the drum. In particular, the second heating zone provides the appropriate energy for heating the substrate temperature after the first heating zone to the substrate temperature for material deposition. The third heating zone or the high power heating zone maintains the substrate temperature at the processing temperature while the substrate is in contact with the processing drum.

[0044] For example, the roller 125 may heat the substrate from room temperature to a first temperature of 30° C.-50° C., for example about 40° C. The roller may heat the substrate by means of a roller heater 131. One or more first heaters in the first heating zone heat the substrate from the first temperature to a second temperature of 60° C.-80° C., for example about 70° C. The heater control of the first heater in the first heating zone is velocity dependent, i.e. dependent on the substrate velocity. In the case of a substrate temperature during deposition, i.e. a third temperature of 70° C.-90° C., for example about 80° C., one or more second heaters in the second heating zone, i.e. a transition heating zone, heat the substrate to prepare for the temperature difference from the second temperature at the end of the first heating zone to the third temperature for substrate processing. In particular, the third temperature may be provided before the substrate contacts the processing drum. The substrate is maintained at the third temperature in the third heating zone, i.e. while the substrate is in contact with the processing drum.

[0045] The embodiments of the present disclosure provide one or more controllers and / or one or more control algorithms for temperature control of a substrate, e.g., a foil, on a processing drum, such as a gas cushion drum. After the substrate contacts the processing drum, the substrate temperature remains essentially constant, even at rest, and especially regardless of web speed. According to some embodiments, which can be combined with other embodiments described herein, the graphite foil can be coated with a thin film, e.g., a lithium-containing thin film. The temperature control in the zone according to the embodiments of the present disclosure controls the thermal expansion of the substrate, thus reducing the occurrence of wrinkles.

[0046] According to an embodiment of the present disclosure, a velocity-dependent pre-heating of the substrate is provided before the substrate contacts the processing drum. According to an embodiment, a material deposition apparatus for depositing evaporated material on a substrate is provided. The material deposition apparatus includes a processing drum having a cooler configured to control the substrate temperature during processing of the substrate on the processing drum, and a roller for guiding the substrate towards the processing drum. A first heater assembly is arranged for heating the substrate in a free span area between the roller and the processing drum. A second heater assembly is arranged for heating the substrate while supported on the processing drum. At least one deposition source is provided downstream of the second heater assembly and along the substrate transport path. The material deposition apparatus includes a substrate velocity sensor providing a velocity signal correlating with the substrate transport velocity, and a controller having an input for the velocity signal, configured to control at least the first heater assembly. According to some embodiments, a sensor can be provided for measuring the temperature of the processing drum 120, for example a cooled coating drum. According to some embodiments, which may be combined with other embodiments described herein, the controller may have inputs for the rate signal, the substrate temperature, and the deposition rate, and the controller may be configured to control at least a first heater assembly.

[0047] Thus, the embodiment reduces the thermal expansion of the substrate, e.g., foil, on the processing drum. Wrinkling can be reduced or avoided. The substrate temperature for deposition, e.g., coating with lithium, is reached before the substrate comes into contact with the processing drum, e.g., a cooled processing drum. The heaters in the free span area, in particular the heaters of the first heater assembly, have a temperature control scheme that depends on the substrate speed. In view of the small heat dissipation from the substrate, e.g., 400 W / m2 can be generated by the first heater assembly. 2 to 5kW / m 2 According to some embodiments, which may be combined with other embodiments described herein, the web speed may be greater than or equal to 1 m / min and / or less than or equal to 12 m / min.

[0048] To further improve the substrate temperature before the substrate contacts the processing drum, a transition heater assembly is provided. The transition heater assembly has a control scheme based on the temperature difference between the temperature after the first heater assembly and the deposition temperature. In particular, the temperature for deposition is reached before the substrate contacts the processing drum. According to some embodiments, which can be combined with other embodiments described herein, the temperature control of the substrate is independent of the substrate speed in the third heating zone. In particular, the processing drum is a cooled processing drum. Thus, in order to have a balance independent of the substrate speed, a ratio of the thermal energy supplied to the substrate and the thermal energy dissipated by the cooled processing drum can be provided. Thus, the heating power of the second heater assembly can be provided with a control scheme dependent on the deposition rate, i.e., a deposition rate signal provided to the controller.

[0049] 2 illustrates a control loop 200 according to an embodiment of the present disclosure. The control loop 200 is specifically utilized for a first heating zone having an input responsive to substrate speed. The control loop 200 may also be used for other heating zones, where the external input may not be temperature dependent as described by an embodiment of the present disclosure.

[0050] A switch 201 is provided to switch between an automatic controller 232 and a manual controller 234. The automatic controller or the manual controller provides a signal to a closed heater control 210. The closed heater control 210 includes a loop controller 212 that provides a signal to a heater 214. A temperature sensor 216, such as a pyrometer or thermocouple, provides feedback to the loop controller. Thus, a closed loop control for the heaters is provided. According to some embodiments, which can be combined with other embodiments described herein, a closed heater control 210 can be provided for each of the heaters. Alternatively, two or more heaters can have a common closed heater control.

[0051] A control output 202 is provided by the control loop 200. FIG. 2 shows a substrate 204 diagrammatically. The substrate 204 provides an external control characteristic for the control loop 200. An external parameter 220 is provided for the control loop 200. According to an embodiment of the present disclosure, the external parameter 220 is a substrate velocity for control of the first heater assembly. A substrate velocity sensor may be provided. The substrate velocity sensor provides a velocity signal that is provided at an input of the controller. The controller controls the first heater assembly based on the signal from the substrate velocity sensor. The external parameter is provided, for example, to an automatic controller 232.

[0052] According to some embodiments, which may be combined with other embodiments described herein, for the free span heater 142, the external parameters 220 may additionally or alternatively be disturbance functions influenced by the substrate type and the substrate speed, for example, look-up table based interpolation functions in the automatic controller 232 that act on such modified disturbances and change the set points in the closed loop controller 210.

[0053] According to some embodiments, which may be combined with other embodiments described herein, a control loop 200 with external parameters 220, being the deposition rate and / or the power provided to the evaporation source, may be provided for control of a second heater assembly arranged to heat the substrate while supported on the processing drum.

[0054] According to some embodiments, which may be combined with other embodiments described herein, the deposition rate may further be read from the evaporation device 110, and may be measured by various methods. This control may affect an automatic controller to cascade external parameters 220, adjust set points in the closed loop controller 210, and modify the control output 202 for the heater 172.

[0055] According to some embodiments, which may be combined with other embodiments described herein, a control loop 200 having an external parameter 220, which is a first temperature, and a second temperature (or temperature difference), may be provided for control of a transition heater assembly arranged to heat a substrate between a first heater assembly and a second heater assembly.

[0056] According to some embodiments, which may be combined with other embodiments described herein, a deposition apparatus and / or material deposition system, e.g., a vacuum deposition system, may include one or more controllers, as exemplarily shown in FIG. 1 and FIG. 2. The one or more controllers may be a general controller having an input for receiving signals as described herein, or may be multiple controllers connected to each other, with a single controller assigned to each heater. The controller may be connected to one or more heaters, a substrate velocity sensor, and one or more temperature sensors. The controller or each of the controllers includes a central processing unit (CPU), a memory, and, for example, support circuits. To facilitate temperature control and / or substrate processing control, the CPU may be one of any form of general-purpose computer processor that may be used in an industrial environment to control various chambers and sub-processors. The memory is coupled to the CPU. The memory, or computer readable medium, may be one or more readily available memory devices, such as random access memory, read-only memory, a hard disk, or any other form of digital storage, either local or remote. The support circuits may be coupled to the CPU to support the processor in a conventional manner. These circuits include cache, power supplies, clock circuits, input / output circuits and related subsystems, etc. Temperature control instructions and / or substrate processing instructions are generally stored in memory as software routines, commonly known as recipes. The software routines may also be stored and / or executed by a second CPU (not shown) remote from the hardware being controlled by the CPU. The software routines, when executed by the CPU, transform the general purpose computer into a special purpose computer (controller) that controls substrate temperature and / or substrate processing, e.g., heater power, deposition power, etc., based on one or more input characteristics according to embodiments of the present disclosure.Although the methods and / or processes of the present disclosure have been described as being implemented as software routines, some of the method steps disclosed therein may be implemented in hardware as well as by a software controller. Thus, the present invention may be implemented in software running on a computer system, and in hardware as an application specific integrated circuit or other type of hardware implementation, or as a combination of software and hardware. The controller may execute or perform the method of depositing evaporated material on a substrate and / or treating a substrate according to embodiments of the present disclosure.

[0057] There may be an associated human machine interface (HMI) or visualization and recipe functionality to implement these control methods. The visualization allows the operator to specify parameters for the substrate 202 and the desired temperature of the substrate. The visualization may also hold recipe parameters that may be selection bands for a simplified control scheme, where the recipe internally adjusts all parameters based on some selected parameters such as substrate type, deposition rate, drum speed, drum temperature, etc.

[0058] According to one embodiment, a method of depositing evaporated material on a substrate is provided. As shown in FIG. 3, the method includes guiding a substrate from a roller toward a processing drum, as indicated by operation 302. A substrate velocity signal is measured, as indicated by operation 304. The substrate is heated with a first heater assembly between the roller and the processing drum in response to the substrate velocity signal, as indicated by operation 306 in FIG.

[0059] According to some embodiments, which may be combined with other embodiments described herein, the substrate is heated on the processing drum using a second heater assembly in response to the deposition rate. Additionally or alternatively, the method further includes measuring a first substrate temperature signal after heating the substrate using the first heater assembly, and measuring a second substrate temperature signal before heating the substrate using the second heater assembly while the substrate is supported on the processing drum. The substrate can be heated using a transition heater assembly in response to a difference between the first substrate temperature signal and the second substrate temperature signal.

[0060] According to some embodiments, which may be combined with other embodiments described herein, a look-up table may be stored in the memory of the controller. Furthermore, the method of depositing evaporated material on a substrate may include generating a control signal for the heater based on the look-up table. The look-up table may be based on a power density as a function of the substrate speed. Additionally or alternatively, a heater temperature, for example, a heater temperature of a heater of a first heater assembly, may be provided as a function of the power density provided on the substrate. Thus, a heater temperature may be provided as a function of the substrate speed. According to yet further implementations, the look-up table may be provided for different substrate materials, for example, a graphite substrate or a copper substrate.

[0061] For example, the look-up table may provide values ​​for the substrate velocity or the velocity of the process drum, respectively, and values ​​for the power density. Alternatively, the power density may be replaced with the heater temperature. According to some embodiments, which may be combined with other embodiments described herein, a bilinear interpolation may be provided for the values ​​in the look-up table. For example, a linear interpolation may be provided for a first value of the substrate velocity and a second value of the second substrate velocity. Such an interpolated substrate velocity may be utilized for further linear interpolation for the power density value for the heater temperature, respectively.

[0062] According to yet further embodiments, which may be combined with other embodiments described herein, the control signals for controlling the various heaters of the heater assembly may be implemented or performed using a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. The general purpose processor may be a microprocessor, but alternatively the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be a graphics processing unit (GPU), such as those commonly used in computer graphics and image processing. The processor may also be implemented as a combination of computing devices, for example a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in combination with a DSP core, or any other such configuration.

[0063] If implemented in software, the functions may be stored or transmitted as one or more instructions or code on a computer-readable medium. Software shall be broadly construed to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media includes both computer storage media and communication media, such as any medium that facilitates transfer of a computer program from one place to another. A processor may be responsible for managing the bus and general processing, including the execution of software modules stored on a computer-readable storage medium.

[0064] A software module may include a single instruction or multiple instructions and may be distributed across several different code segments, among different programs, and across multiple storage media. A computer-readable medium may include several software modules. A software module includes instructions that, when executed by a device such as a processor, cause a processing system to perform various functions. A software module may include a transmitting module and a receiving module. A software module may be configured to be trained. A software module may receive training data based on a plurality of measured temperatures and may be trained to provide control data from the training data.

[0065] Software for providing temperature control according to embodiments of the present disclosure may include a machine learning model. To train a machine learning model, such as a CNN model, training data is provided to the machine learning model to generate an output. The machine learning model typically has a set of initialization parameters that affect how the machine learning model processes data. The training data typically has a ground truth (e.g., known value) classification. The output is typically evaluated against this ground truth. The results of this evaluation can be used to adjust or update the parameters of the machine learning model in subsequent runs so that the machine learning model produces more accurate outputs. Once fully trained, the machine learning model accepts inputs in the same form as the data used to train the machine learning model and generates outputs based on the inputs. The CNN model used to implement temperature control of the heaters of one or more heater assemblies is trained using training data consisting of labeled images. The training data can be substrate temperatures at different locations of the vacuum processing system resulting from various control signals for the heaters of one or more heater assemblies.

[0066] Embodiments of the present disclosure provide one or more of the following advantages: The substrate temperature can be set for various operating conditions, such as the substrate speed and / or deposition rate to be adjusted for the reduction of substrate wrinkling, particularly on the processing drum. The substrate temperature can be adjusted in the free span area based on the substrate speed, adjusted in the transition region for temperature difference, and adjusted on the processing drum depending on the deposition rate (or power of the deposition source) and the cooling power of the substrate support, e.g., a cooled processing drum.

[0067] While the above is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope of the disclosure, the scope of which is determined by the following claims.

Claims

1. 1. A material deposition apparatus for depositing evaporated material on a substrate, the material deposition apparatus comprising: a processing drum having a cooler configured to control a substrate temperature during processing of the substrate on the processing drum; a roller for guiding the substrate towards the processing drum; a first heater assembly positioned to heat the substrate in a free span area between the roller and the processing drum; a second heater assembly positioned to heat the substrate while supported on the processing drum; at least one deposition source disposed along a substrate transfer path downstream from the second heater assembly; a substrate speed sensor providing a speed signal correlating with the substrate transport speed; a controller having an input for the speed signal and configured to control at least the first heater assembly based on the speed signal; 1. A material deposition apparatus comprising:

2. a first temperature sensor disposed along the substrate transfer path downstream of the first heater assembly; The material deposition apparatus of claim 1 further comprising:

3. a second temperature sensor disposed along the substrate transfer path downstream of the second heater assembly; The material deposition apparatus of claim 1 or 2, further comprising:

4. a transition heater assembly disposed between the first heater assembly and the second heater assembly for heating the substrate; The material deposition apparatus of claim 1 or 2, further comprising:

5. a transition temperature sensor disposed along the substrate transfer path downstream of the transition heater assembly; The material deposition apparatus of claim 4 further comprising:

6. a transition heater controller having an input for a signal of the transition temperature sensor for controlling the transition heater assembly in response to the signal of the transition temperature sensor; The material deposition apparatus of claim 5 further comprising:

7. A second heater controller having an input for a deposition rate signal. The material deposition apparatus of claim 1 or 2, further comprising:

8. A second heater controller having an input for a deposition rate signal. The material deposition apparatus of claim 6 further comprising:

9. 3. The material deposition apparatus of claim 1 or 2, wherein the cooling is provided by a gas cushion directing a cooling gas between the processing drum and the substrate.

10. The material deposition apparatus of claim 6 , wherein the cooling is provided by a gas cushion that directs cooling gas between the process drum and the substrate.

11. 9. The material deposition apparatus of claim 8, wherein the cooling is provided by a gas cushion that directs cooling gas between the process drum and the substrate.

12. A method of depositing evaporated material onto a substrate using the material deposition apparatus of claim 1, the method comprising: guiding the substrate from the roller towards the processing drum; measuring the velocity signal with the substrate velocity sensor; heating the substrate from a first substrate temperature to a second substrate temperature with the first heater assembly based on the rate signal; heating the substrate on the processing drum with the second heater assembly in response to a deposition rate; A method comprising:

13. measuring a first substrate temperature signal after heating the substrate with the first heater assembly; measuring a second substrate temperature signal prior to heating the substrate with the second heater assembly while the substrate is supported on the process drum; The method of claim 12 further comprising:

14. The material deposition apparatus further comprising a transition heater assembly positioned to heat a substrate between the first heater assembly and the second heater assembly; The method further comprising: heating the substrate with the transition heater assembly in response to a difference between the first substrate temperature signal and the second substrate temperature signal. The method of claim 13 further comprising:

15. A material deposition system comprising: A material deposition apparatus according to claim 1, the controller comprises a processor and a memory storing instructions that, when executed by the processor, cause a plurality of operations to be performed for depositing the evaporated material on the substrate using the material deposition apparatus; The plurality of operations include: guiding the substrate from the roller towards the processing drum; receiving the velocity signal from the substrate velocity sensor; heating the substrate from a first substrate temperature to a second substrate temperature using the first heater assembly based on the velocity signal to provide velocity dependent heating of the substrate in the free span area before the substrate contacts the process drum; depositing the evaporated material onto the substrate using the at least one deposition source as the substrate moves along the substrate transport path of the processing drum; Including, Material Deposition System.

16. The method of claim 15, wherein the plurality of operations further comprises heating the substrate on the processing drum with the second heater assembly based on a deposition rate.

16. The material deposition system of claim 15.

17. 16. The material deposition system of claim 15, wherein a look-up table is stored in the memory to correlate substrate speed with power density of the first heater assembly.

18. 20. The material deposition system of claim 17, wherein the controller provides a bilinear interpolation of the data in the lookup table.

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