Heating apparatus, evaporation source apparatus, film forming apparatus, film forming method, and method for manufacturing electronic device

Abstract

The invention relates to a heating apparatus, an evaporation source apparatus, a film forming apparatus, a film forming method, and a method for manufacturing an electronic device. A heating device for heating a container having an opening for discharging a vapor deposition material, a first region, and a second region separated from the opening from the first region, the heating device having a first heater for heating the first region, a second heater for heating the second region, and a control unit for independently controlling each of the heaters, the second heater includes a first portion and a second portion, the distance between the second portion and the first heater is smaller than the distance between the first portion and the first heater, the control unit integrally controls the first portion and the second portion when controlling the second heater, and the heating device further includes an inner heat reflecting member disposed between the second portion and the container. By blocking heat emitted from the second portion to the container, the amount of heat incident on a region facing the first portion in the container is greater than the amount of heat incident on a region facing the second portion.

Description

[0001] This application is a divisional application of the invention patent application entitled "Heating device, evaporation source device, film forming device, film forming method and manufacturing method of electronic device", with an application date of December 17, 2019 and application number 201911297341.9. Technical Field

[0002] The present invention relates to a heating device, an evaporation source device, a film forming device, a film forming method and a method for manufacturing an electronic device. Background Art

[0003] In recent years, organic EL devices, which utilize organic materials to generate electroluminescent light, have attracted significant attention as a type of display. The manufacturing of organic electronic devices, such as these organic EL displays, involves forming films by depositing organic materials, metal electrode materials, and other materials onto a substrate using an evaporation source.

[0004] The evaporation source device used in the vapor deposition process has two functions: serving as a container for the vapor deposition material; and heating the vapor deposition material to increase its temperature, causing it to evaporate and adhere to the substrate surface. To enhance this heating function and achieve superior film formation, evaporation source devices that can uniformly heat the vapor deposition material have been proposed.

[0005] Patent Document 1 (Japanese Patent Application Laid-Open No. 2019-031705) discloses a so-called dual-heater type evaporation source device heating device that divides a container (crucible) containing evaporation material into two different regions (upper and lower regions) in the height direction, independently controlling the heating of the upper and lower regions. In Patent Document 1, heating of the upper heater corresponding to the upper region and the lower heater corresponding to the lower region is controlled based on the amount of evaporation material in the container and the progress of evaporation, thereby preventing sudden boiling and adhesion of material to the container opening.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Publication No. 2019-031705

[0009] Problems to be solved by the invention

[0010] However, in the heating control of the evaporation source device, it is required to further suppress problems such as sudden boiling, adhesion of the material to the container opening, and degradation of the vapor deposition material due to excessive heating, so as to perform high-quality film formation. Summary of the Invention

[0011] The present invention has been made in view of the above problems, and an object of the present invention is to provide a technique for properly heating a vapor deposition material to form a suitable film.

[0012] Solutions to Problems

[0013] In order to achieve the above-mentioned object, the present invention adopts the following structure.

[0014] A heating device for heating a container containing a vapor deposition material, characterized in that:

[0015] The container includes an opening for releasing the heated vapor deposition material, a first region, and a second region that is a region farther from the opening than the first region.

[0016] The heating device comprises:

[0017] a first heater, the first heater heating the first area;

[0018] a second heater that heats the second region; and

[0019] a control unit that independently controls the first heater and the second heater,

[0020] The second heater includes a first portion and a second portion, the second portion being closer to the first heater than the first portion.

[0021] The control unit controls the first portion and the second portion integrally when controlling the second heater.

[0022] The heating device further includes an inner heat reflecting member, which is disposed between the second portion and the container and faces the second portion, and blocks heat emitted from the second portion to the container.

[0023] The heating device further includes a second inner heat reflecting member disposed between the first and second portions and the container and facing the first and second portions to block heat released from the first and second portions to the container.

[0024] The present invention also adopts the following structure. That is,

[0025] A heating device for heating a container containing a vapor deposition material, characterized in that:

[0026] The container includes an opening for releasing the heated vapor deposition material, a first region, and a second region that is a region farther from the opening than the first region.

[0027] The heating device comprises:

[0028] a first heater, the first heater heating the first area;

[0029] a second heater that heats the second region; and

[0030] a control unit that independently controls the first heater and the second heater,

[0031] The second heater includes a first portion and a second portion, the second portion being closer to the first heater than the first portion.

[0032] The control unit controls the first portion and the second portion integrally when controlling the second heater.

[0033] The heating device further includes an inner heat reflecting component, which is arranged between the second part and the container. By blocking the heat released from the second part to the container, the amount of heat incident on the area of ​​the container facing the first part is greater than the amount of heat incident on the area of ​​the container facing the second part.

[0034] The present invention also adopts the following structure. That is,

[0035] A heating device for heating a container containing a vapor deposition material, characterized in that:

[0036] The container includes an opening for releasing the heated vapor deposition material, a first region, and a second region that is a region farther from the opening than the first region.

[0037] The heating device comprises:

[0038] a first heater, the first heater heating the first area;

[0039] a second heater that heats the second region; and

[0040] a control unit that independently controls the first heater and the second heater,

[0041] The second heater includes a first portion and a second portion, the second portion being closer to the first heater than the first portion.

[0042] The control unit controls the first portion and the second portion integrally when controlling the second heater.

[0043] The heating device further includes an outer heat reflecting component, which is arranged on the side opposite to the container across the first part. By reflecting heat released from the first part to the outside of the heating device, the amount of heat incident on the area of ​​the container facing the first part is greater than the amount of heat incident on the area of ​​the container facing the second part.

[0044] The present invention also adopts the following structure. That is,

[0045] A film forming method for forming a film on a substrate as a vapor-deposited object using a vapor deposition material, characterized in that:

[0046] The method comprises the steps of heating the deposition material contained in the container using a heating device to evaporate the deposition material.

[0047] The container includes an opening for releasing the heated vapor deposition material, a first region, and a second region that is a region farther from the opening than the first region.

[0048] The heating device comprises:

[0049] a first heater, the first heater heating the first area;

[0050] a second heater that heats the second region; and

[0051] a control unit that independently controls the first heater and the second heater,

[0052] The second heater includes a first portion and a second portion, the second portion being closer to the first heater than the first portion.

[0053] The control unit controls the first portion and the second portion integrally when controlling the second heater.

[0054] The heating device further includes an inner heat reflecting component, which is arranged between the second part and the container. By blocking the heat released from the second part to the container, the amount of heat incident on the area of ​​the container facing the first part is greater than the amount of heat incident on the area of ​​the container facing the second part.

[0055] The present invention also adopts the following structure. That is,

[0056] A film forming method for forming a film on a substrate as a vapor-deposited object using a vapor deposition material, characterized in that:

[0057] The method comprises the steps of heating the deposition material contained in the container using a heating device to evaporate the deposition material.

[0058] The container includes an opening for releasing the heated vapor deposition material, a first region, and a second region that is a region farther from the opening than the first region.

[0059] The heating device comprises:

[0060] a first heater, the first heater heating the first area;

[0061] a second heater that heats the second region; and

[0062] a control unit that independently controls the first heater and the second heater,

[0063] The second heater includes a first portion and a second portion, the second portion being closer to the first heater than the first portion.

[0064] The control unit controls the first portion and the second portion integrally when controlling the second heater.

[0065] The heating device further includes an outer heat reflecting component, which is arranged on the side opposite to the container across the first part. By reflecting heat released from the first part to the outside of the heating device, the amount of heat incident on the area of ​​the container facing the first part is greater than the amount of heat incident on the area of ​​the container facing the second part.

[0066] Effects of the Invention

[0067] According to the present invention, a technique for satisfactorily heating a vapor deposition material and performing appropriate film formation can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0068] Figure 1 It is a schematic cross-sectional view showing the structure of a film forming apparatus.

[0069] Figure 2 (a) to (d) are diagrams for studying the arrangement of heaters and the heating of the container.

[0070] Figure 3 (a) and (b) are diagrams for explaining the structures of a container and a heater of an evaporation source device.

[0071] 4( a ) and ( b ) are diagrams showing a configuration common to each embodiment of the present invention.

[0072] Figure 5 (a) to (c) are diagrams for explaining the configuration of the first embodiment.

[0073] Figure 6 (a) to (c) are diagrams for explaining the structure of the second embodiment.

[0074] Figure 7 This is a diagram for explaining the structure of embodiment 3.

[0075] Figure 8 (a) and (b) are diagrams for explaining a method for manufacturing an organic electronic device.

[0076] Description of Reference Numerals

[0077] 242: Evaporation material, 244: Container, 245: Heating device, 246: Heater, 246a: Upper heater, 246b: Lower heater, 246b1: First portion, 246b2: Second portion, 248: Reflector, 270: Control unit DETAILED DESCRIPTION

[0078] The following describes preferred embodiments and examples of the present invention with reference to the accompanying drawings. However, the following embodiments and examples merely illustrate preferred configurations of the present invention and do not limit the scope of the present invention to these configurations. Furthermore, unless otherwise specified, the following description of the hardware and software configurations, processing flow, manufacturing conditions, dimensions, materials, and shapes of the device are not intended to limit the scope of the present invention to these configurations.

[0079] The present invention relates to a heating device, an evaporation source device, a film-forming device, a film-forming method, and a method for manufacturing an electronic device, for forming a thin film on a substrate by evaporation. The present invention can also be realized as a heating control method, a film-forming control method, a method for controlling an evaporation source device, a program for causing a computer to execute these control methods, and a storage medium storing the program. The storage medium can be a non-transitory computer-readable storage medium.

[0080] The present invention can be preferably applied to, for example, a device for forming a thin film (material layer) of a desired pattern on the surface of a substrate as a vapor-deposited body by vacuum evaporation. As the material of the substrate, any material such as glass, resin, metal, etc. can be selected. It should be noted that the vapor-deposited body of the evaporation source device is not limited to a flat substrate. For example, a mechanical part with concave-convex and open openings can also be used as the vapor-deposited body. In addition, as the vapor deposition material, any material such as an organic material, an inorganic material (metal, metal oxide, etc.) can be selected. In addition, not only an organic film can be formed, but also a metal film can be formed. Specifically, the technology of the present invention can be applied to manufacturing devices for electronic devices, optical components, etc., and in particular, it is suitable for the manufacture of organic electronic devices (for example, organic EL display devices, thin-film solar cells, organic CMOS image sensors).

[0081] <Structure of Evaporation Source Device>

[0082] Figure 1 It is a cross-sectional view schematically showing the structure of a vapor deposition device (film forming device). The film forming device has a vacuum chamber 200. The interior of the vacuum chamber 200 is maintained as a vacuum environment or an inert gas environment such as nitrogen. It should be noted that the vacuum mentioned here refers to a state filled with a gas with a pressure lower than the normal atmospheric pressure (typically 1023hPa). Inside the vacuum chamber 200, there are roughly arranged a substrate 10 as a vapor-deposited body held by a substrate holding unit (not shown), a mask 220, an evaporation source device 240 and a vapor deposition detector 285.

[0083] After being transported into the vacuum chamber 200 by a transport robot (not shown), the substrate 10 is held by a substrate holding unit and fixed parallel to the horizontal plane (XY plane) during film formation. It should be noted that the term "parallel" does not only mean strictly mathematical parallelism, but also includes situations where the angle between the horizontal plane and the substrate 10 is small, such as between 0° and 5°. The substrate holding unit holds the substrate 10 using supporting members such as receiving claws for placing the substrate 10 and pressing members such as clamps for pressing and holding the substrate.

[0084] The mask 220 is a mask, such as a metal mask, having an opening pattern corresponding to a predetermined thin film pattern to be formed on the substrate 10. Before film formation begins, the substrate 10 and the mask 220 are aligned and their positional relationship is fixed.

[0085] It should be noted that, in the present embodiment, the substrate 10 is fixed parallel to the horizontal plane during film formation, but this is not limited to this. The substrate 10 can be fixed crosswise to the horizontal plane during film formation, or it can be fixed perpendicularly to the horizontal plane. In addition, in the present embodiment, a structure of upward deposition is adopted in which the film is formed with the film forming surface of the substrate 10 facing downward in the direction of gravity, but this is not limited to this. A structure of downward deposition can also be adopted in which the film is formed with the film forming surface of the substrate 10 facing upward in the direction of gravity. Alternatively, a structure of film formation can also be adopted in which the substrate 10 is vertically upright, that is, in which the film forming surface of the substrate 10 is parallel to the direction of gravity.

[0086] A cooling plate may be provided within the vacuum chamber to suppress temperature increases of the substrate 10. Furthermore, the vacuum chamber 200 may include a mechanism for aligning the substrate 10, such as an actuator for moving one of the substrate 10 and the mask 220 relative to the other in the X or Y direction, a driving member such as an actuator for a clamping mechanism for holding the substrate, and a camera for imaging the substrate 10. To ensure uniform film formation, an evaporation source drive mechanism 250 may be provided within the vacuum chamber to move the evaporation source device 240.

[0087] The evaporation source device 240 generally comprises a container 244 capable of containing a deposition material 242, and a heating device 245 for heating the material. The heating device 245, disposed on the periphery of the container 244, comprises at least a heater 246 and may also include a fixing member for securing the heater 246. A sheathed heater using a heating wire is used as the heater 246. This figure shows a cross-section of the sheathed heater's heating wire wound around the container 244.

[0088] It should be noted that the heater 246 and the control unit 270 can also be considered together as a heating device 245. In addition, the control unit 270, the container 244 and the heater 246 can also be considered together as an evaporation source device. The structure and control of the heater 246 will be discussed in detail later. The evaporation source device 240 can also include a reflector as a reflective component for improving heating efficiency. The evaporation source device 240 can also include a frame, a baffle, etc. that can accommodate the entire structural element. It should be noted that, Figure 1 The shapes, positional relationships, and dimensional ratios of the components are merely examples.

[0089] As materials for the container 244, ceramics, metals, carbon materials, etc. are known, but not limited to them. A material that is preferred in terms of the relationship between the physical properties of the evaporation material 242 and the heating temperature of the heater 246 is used. In addition, any material can be used as long as it can be used as a container (crucible) for the evaporation material. As the heater 246, a resistance heating type heater such as a sheath heater and a metal wire is known, but not limited to them, as long as it has heating performance that evaporates the evaporation material 242. As described later, there is no limitation on the type as long as it can heat while controlling the temperature of multiple parts of the container 244 separately. In addition, regarding the shape of the heater, in addition to Figure 1 In addition to the linear shape, any other shapes may be adopted, such as plate shape, grid shape, etc. The reflector is a heat-insulating material (heat-insulating material) that improves thermal efficiency, and can be made of metal, for example, but is not limited thereto.

[0090] The vapor deposition detector 285 is used by the control unit 270 to measure the vapor deposition rate of the vapor deposition material 242 and perform heating control. As the vapor deposition detector 285, a quartz film thickness meter or the like can be used.

[0091] The control unit 270 controls the evaporation source device 240, such as controlling the timing of starting and ending heating, and controlling the temperature. When a baffle is provided, the control unit 270 also controls the timing of opening and closing the baffle. When an evaporation source drive mechanism is provided, the control unit 270 also controls the drive of the evaporation source drive mechanism (controlling the movement of the evaporation source). It should be noted that the control unit 270 can be composed of a plurality of control components. The plurality of control components include, for example, a heating control component, a baffle control component, an evaporation source drive control component, and the like. In addition, when control can be performed for each portion of the heater 246, a heating control component can be provided for each portion. The control unit 270 can also serve as a control component for mechanisms other than the evaporation source device 240, such as conveying the substrate 10 and aligning the substrate 10 with the mask 220.

[0092] The control unit 270 is composed of, for example, a computer having a processor, memory, storage, I / O, UI, etc. In this case, the functions of the control unit 270 are realized by the processor executing a program stored in the memory or storage. As the computer, a general-purpose computer can be used, or an embedded computer or PLC (programmable logic controller) can be used. Alternatively, part or all of the functions of the control unit 270 can be composed of a circuit such as an ASIC or FPGA. In the case where the film forming system has multiple film forming devices, the control unit 270 can be provided for each film forming device, or a single control unit 270 can control multiple film forming devices.

[0093] When the evaporation material 242 is stored in the container, the heater 246 is activated under the control of the control unit 270, heating the evaporation material 242. After the temperature has sufficiently increased, the mask 220 and substrate 10 are introduced into the vacuum chamber 200, and alignment between the substrate 10 and the mask 220 is performed. Subsequently, when the shutter of the evaporation source device 240 is opened from the closed position, the evaporation material 242 is released. The evaporation material 242 adheres to the surface of the substrate 10, forming a thin film. Co-evaporation can be performed by pre-storing different types of evaporation materials in multiple containers. The thickness of the formed film is measured and controlled by the evaporation detector 285, allowing a film of the desired thickness to be formed on the substrate. To achieve uniform film formation, evaporation can be performed while rotating the substrate 10 or moving the evaporation source device using an evaporation source drive mechanism. Furthermore, multiple evaporation sources can be heated simultaneously, depending on the size of the substrate. The shape of the container 244 is arbitrary. For example, a nozzle that improves the directivity of the released deposition material may be provided at the opening. In addition, the evaporation source may be any of a point evaporation source, a linear evaporation source, and a planar evaporation source.

[0094] As described later, a multilayer structure can be formed by depositing a different type of evaporation material on a substrate already deposited with a certain evaporation material. In this case, the evaporation material in the container can be replaced, or the container itself can be replaced with a container storing a different type of evaporation material. Furthermore, multiple evaporation source devices can be installed in the vacuum chamber and used interchangeably, or the substrate 10 can be removed from the current film-forming device and transferred to another film-forming device equipped with an evaporation source device storing a different type of evaporation material.

[0095] <Research related to heating control>

[0096] Reference Figure 2 , the inventors' research results on the relationship between the structures of the upper heater 246a and the lower heater 246b, the temperature change of the container 244, and the evaporation of the deposition material are described. Figure 2 (a) is a first study example, showing a situation where the upper heater 246a and the lower heater 246b are arranged continuously and at the same density. In this example, a predetermined power is always input to the upper heater 246a, and the power input to the lower heater 246b is changed as the vapor deposition progresses.

[0097] It should be noted that the term "heater density" is used herein to refer to the number of heaters per unit cross-sectional area or the cross-sectional area of ​​heaters per unit cross-sectional area, as measured in a cross-section taken along a plane perpendicular to the heater lines. For example, a rectangle enclosing the heater lines and minimizing its area could be drawn in the cross-section, and the value obtained by dividing the number of enclosed heater lines or the total cross-sectional area of ​​the heater lines by the area of ​​the rectangle could be used as the heater density. The following description also applies when considering heater density as the number of heaters per unit distance in the height direction.

[0098] Figure 2 (b) means Figure 2 In the configuration (a), this graph shows the temperature distribution of the deposition material 242 within the container 244 when a predetermined amount of power is input to the upper heater 246a and the power input to the lower heater 246b is varied. The horizontal axis represents temperature, with temperature t1 being the evaporation temperature at which the deposition material 242 evaporates, and temperature t2 being the degradation starting temperature at which the deposition material 242 begins to degrade. The vertical axis corresponds to the height position within the container. This graph shows the gradual progress of heating as the temperature of the lower heater 246b increases from state 1-1 to state 1-3.

[0099] exist Figure 2 In (b), in state 1-1, where the temperature of the lower heater 246b is relatively low, the degradation starting temperature t2 is not exceeded at the uppermost portion of the container 244. However, as the amount of the vapor deposition material 242 decreases, the controller 270 increases the temperature of the lower heater 246. As the temperature passes from state 1-2 to state 1-3, the temperature at the uppermost portion of the container 244 exceeds the degradation starting temperature t2 (indicated by reference symbol A). As a result, there is a possibility of material degradation.

[0100] in addition, Figure 2 (c) In view of Figure 2 (b) The second case study was conducted based on the phenomenon. Figure 2 In the structure of (c), the upper heater 246a and the lower heater 246b are arranged with a gap in between. This structure is intended to prevent excessive heating of the upper portion of the container even when the temperature of the lower heater 246b rises. Figure 2 As shown in (d), even if the lower heater 246b is heated and the temperature rises, the non-heated portion exists in the middle portion, so the temperature rise is suppressed as shown in state 2-2.

[0101] in the case of Figure 2(c) Structure, even at the top of the container, the temperature rises relatively slowly, which can suppress the degradation of the evaporation material 242. However, since no heater is configured in the portion corresponding to the middle portion, the heat supply to the middle portion is insufficient, resulting in an inversion phenomenon in which the temperature of the lower region in the container is higher than that of the middle portion (indicated by the reference symbol B). In this way, during evaporation, in the temperature distribution of the portion where the temperature decreases from the bottom of the container 244 toward the opening, even when the temperature of the evaporation material 242 near the bottom exceeds the evaporation point t1, the evaporation material 242 in the middle portion may still be in a solid state. Therefore, the evaporated evaporation material 242 becomes covered by the solid, which may cause sudden boiling.

[0102] <Structure of container and heating device>

[0103] use Figure 3 The schematic cross-sectional view further illustrates the structure of the container 244 and the heater 246. Figure 3 (a) is a diagram for explaining the terms indicating the various parts of the container 244. In this figure, parts not related to the explanation are omitted.

[0104] exist Figure 3 In (a), when the container 244 is divided in the height direction, the area close to the upper surface 244m of the container 244 is referred to as the "upper area 244a". The upper area 244a is close to the opening through which the evaporated deposition material 242 is released. In addition, when the container 244 is divided in the height direction, the area close to the bottom surface 244n of the container 244 is referred to as the "lower area 244b". The proportions of the upper area and the lower area in the height of the container are not limited to the example shown in the figure. It should be noted that, in the case where the container 244 has a nozzle protruding from the upper surface, or the container 244 is provided with a reduced diameter, there are sometimes multiple side surfaces in the height direction. In this case, the upper area 244a is set to the uppermost area when the container 244 is divided in the height direction.

[0105] In addition, the area of ​​the lower region 244b that is farther away from the upper region 244a is sometimes referred to as the "first area 244b1 of the lower region." In addition, the area of ​​the lower region 244b that is farther away from the upper region 244a is sometimes referred to as the "second area 244b2 of the lower region." The proportions of the first area 244b1 and the second area 244b2 in the height direction of the container within the lower region 244b are not limited to the example shown in the figure. It should be noted that the second area 244b2 of the lower region is located between the upper region 244a and the first area 244b1 of the lower region. Therefore, the second area 244b2 of the lower region may also be referred to as the middle area.

[0106] Figure 3 (b) is a diagram for further explaining the structure of the heating device 245. Here, for simplicity, only the cross section of the heater 246 in the heating device 245 is shown.

[0107] Upper heater 246a (first heater) is positioned opposite upper region 244a. Therefore, when power is supplied to upper heater 246a, upper region 244a receives the most heat. Furthermore, lower heater 246b (second heater) is positioned opposite lower region 244b. Therefore, when power is supplied to lower heater 246b, lower region 244b receives the most heat. It should be noted that the lower region is positioned below the upper region in the direction of gravity.

[0108] The portion of the lower heater 246b that faces the first region 244b1 of the lower area is sometimes referred to as the "first portion 246b1 of the lower heater." Similarly, the portion of the lower heater 246b that faces the second region 244b2 of the lower area is sometimes referred to as the "second portion 246b2 of the lower heater." The second portion 244b2 is located above the first portion 244b1 in the direction of gravity.

[0109] It should be noted that when considering the correspondence between each zone and each heater, the term "opposing position" does not need to be strictly understood. Even if there is a slight positional offset in the height direction between the zone and the heater, it is sufficient as long as it affects the temperature of the heating target position.

[0110] The control unit 270 can independently control the upper heater 246a and the lower heater 246b. The control contents include the start / end of heating, temperature change, etc. For example, when a sheath heater is used, the power applied (supplied) to the heating wire is changed. It should be noted that the control unit 270 performs a single control on the first part 246b1 and the second part 246b2 of the lower heater. That is, the start / end timing of heating and the current flowing between the upper heater 246a and the lower heater 246b are sometimes different, but the control contents are the same between the first part 246b1 and the second part 246b2 of the lower heater. The above-mentioned control can typically be achieved by constituting the first part 246b1 and the second part 246b2 of the lower heater with a single heating wire.

[0111] Furthermore, the control unit 270 controls the power input to only one of the upper heater 246a and the lower heater 246b to vary, while inputting a constant power to the other. Thus, in the present invention, in a dual-heater configuration, the power input to only one heater is varied, while a predetermined fixed power is input to the other, thereby simplifying the control mechanism and control method.

[0112] The control unit 270 controls the upper heater 246a and the lower heater 246b respectively in a method corresponding to the type of heating component. For example, when using a resistive heating heater, the power supply to the heating wire is controlled. More specifically, the temperature is increased or decreased by increasing or decreasing the current density of the resistive heating heater. The control unit 270 determines the control conditions based on the input values ​​input by the user through the computer UI, etc., and conditions related to the device structure and the evaporation material (for example, the performance of the heater, the shape and material of the container, the configuration and characteristics of the reflector, the characteristics of other film-forming devices, the type of evaporation material, the amount of evaporation material contained in the container). It is also preferred to use the detection values ​​of the evaporation detector 285 and the temperature sensor (not shown) for control. In addition, it is also preferred to store the preferred control conditions corresponding to the evaporation material and device structure in the form of a table or mathematical formula in the memory in advance and make the control unit 270 refer to them. The heater such as the lower heater can be a structure having a heating wire arranged in a spiral wound around the container.

[0113] <Features of the Invention>

[0114] Therefore, the inventors conducted further research and came up with a heating device structure that can appropriately control the temperature within the container to reduce the degradation of the vapor deposition material and the occurrence of sudden boiling. First, the common structure and principle of the present invention are explained using Figure 4, and then the description of each specific embodiment is turned.

[0115] In FIG4(a), for ease of explanation, the heating device 245 is divided into a portion corresponding to the upper region 244a (reference numeral 245a), a portion corresponding to the first region 244b1 of the lower region (reference numeral 245b1), and a portion corresponding to the second region 244b2 of the lower region (reference numeral 245b2). The control unit 270 heats the portion 245a facing the upper region 244a with constant power input, and varies the power input to the portion 245b facing the lower region 244b (245b1 and 245b2) as vapor deposition proceeds.

[0116] At this time, Figure 4(a) shows the amount of heat incident from the heating device 245 relative to each area of ​​the container 244. The thickness of the hollow arrow is the amount of heat incident from the heating device 245 per unit area. It should be noted that the issue here is the difference in heat inside the part corresponding to the lower heater, so the part corresponding to the upper heater (reference numeral 245a) is omitted. As can be seen from the figure, the amount of heat incident on the first area 244b1 of the lower area is greater than the amount of heat incident on the second area 244b2 of the lower area. The various embodiments of the present invention are characterized in that the power control input to each part in such a lower area is not changed, but temperature control that is different for each part in the lower area is achieved through a physical structure. It should be noted that when comparing the amount of heat incident on each area, for example, it is sufficient to compare the amount of heat incident per unit area of ​​the container surface or the amount of heat incident per unit volume of the container.

[0117] Figure 4(b) is used to Figure 2 (a) and Figure 2 (c) is a graph illustrating the effect of the structure of FIG4(a). In the structure of FIG4(a), the heat incident on the second area 244b2 of the lower area is greater than Figure 2 (a) is less likely to occur. Therefore, even if heating is performed, the temperature of the uppermost portion of the container does not rise excessively, thereby suppressing overheating. Figure 2 (c) is different in that a heater is also provided in the portion corresponding to the second region 244b2 of the lower region. Therefore, the portion where the temperature drops from the bottom of the container 244 toward the opening during vapor deposition disappears. As a result, no Figure 2 Since there is no temperature reversal phenomenon as in state 2-2 of (d), sudden boiling is unlikely to occur.

[0118] Thus, in the present invention, even if the power input to the lower heater 246b is constant, the amount of heat per unit area incident on the second region 244b2 of the lower region is less than the amount of heat per unit area incident on the first region 244b1 of the lower region. Therefore, a relatively simple structure can be used to suppress overheating and sudden boiling, thereby achieving appropriate film formation. It should be noted that, here, the power to the upper heater 246a is set constant, and the power to the lower heater 246b is set variable. However, conversely, the power to the lower heater 246b can also be set constant, and the power to the upper heater 246a can be set variable. The control unit 270 integrally controls the first portion 246b1 and the second portion 246b2 of the lower heater 246b.

[0119] [Implementation Method 1]

[0120] use Figure 5The structure of this embodiment will be described. It should be noted that, for simplicity, the diagram omits the components other than the container 244, heater 246, and reflector 248. In this diagram, the power to the upper heater 246a is fixed, while the power to the lower heater 246b is variable.

[0121] In this embodiment, the density, number of turns, resistivity, and wire thickness (wire diameter) of lower heater 246 are constant, with no difference between first section 246b1 and second section 246b2. Therefore, the amount of heat generated per unit cross-sectional area remains constant at all locations along the height of lower heater 246b. Therefore, in this embodiment, reflectors 248 are provided to vary the amount of heat reaching container 244 from the heating wires for each region of lower heater 246b.

[0122] The reflector included in the heating device 245 of the present embodiment is an inner reflector 248 a (inner heat reflecting member) that is arranged inside the heating line and outside the container 244 .

[0123] Figure 5 (a) is the first installation example of this embodiment. The inner reflector 248a is positioned between the second portion 246b2 of the lower heater and the second region 244b2 of the lower area of ​​the container 244. Because heat is reflected by the inner reflector 248a, the radiation heat transfer rate between the second portion 246b2 of the lower heater and the second region 244b2 can be made lower than the radiation heat transfer rate between the first portion 246b1 of the lower heater and the first region 244b1. This creates a structure where the second portion 246b2 of the lower heater is shielded from heat entering the container. It should be noted that the "radiation heat transfer rate" referred to here refers to the amount of radiation heat transferred per unit area in a cross-section of a region cut along a plane perpendicular to the direction of heat transfer when radiant heat is transferred through the region. If the amount of radiant heat from the heat source is the same, a lower "radiation heat transfer rate" means that the heat is shielded and attenuated in that region.

[0124] Figure 5 (b) is the second installation example of this embodiment. Figure 5(a) In addition to the identical inner reflector (first inner reflector 248a1: first inner heat reflecting component), a second inner reflector 248a2 (second inner heat reflecting component) is also provided. The second inner reflector 248a2 is positioned between the entire lower heater 246b and the entire lower region 244b. As a result, when comparing the first region 244b1 and the second region 244b2, the amount of heat incident per unit area on the first region 244b1 increases. It should be noted that the material, structure, and processing methods of the first inner reflector 248a1 and the second inner reflector 248a2 may be the same or different. In the figure, the first inner reflector 248a1 is positioned inward of the second inner reflector 248a2, but the opposite may also be true.

[0125] Figure 5 (c) is a third installation example of this embodiment. The inner reflector 248a in this figure includes a first reflective portion 248a3 facing the first area 244b1 and a second reflective portion 248a4 facing the second area 244b2. The second reflective portion 248a4 has a higher thermal reflectivity per unit area than the first reflective portion 248a3. In other words, the second reflective portion 248a4 has a lower radiative heat transfer rate than the first reflective portion 248a3. Such differences in reflectivity or radiative heat transfer rate can be achieved by known methods, such as changing the material, surface finishing method, color, presence of holes, thickness, etc., of each reflective portion.

[0126] It should be noted that in Figure 5 In the structure of (b), if the first inner reflector 248a1 and the second inner reflector 248a2 are considered together as the "inner reflector", then Figure 5 Similarly, in case (c), it can be considered that Figure 5 The structure (b) is a structure in which the reflectivity or the radiation heat transfer rate is different between the upper and lower parts of the inner reflector.

[0127] According to this embodiment, the amount of heat incident on the second region 244b2 of the lower region 244b, which is closer to the upper region 244a, is smaller than the amount of heat incident on the first region 244b1. As a result, in a device with a dual-heater structure, excessive heating of the uppermost portion of the container 244 and sudden boiling of the evaporation material 242 can be suppressed with a simple structure, thereby achieving good film formation.

[0128] It should be noted that the height-wise orientation of the reflector and various portions of the heater, or the orientation of the reflector and various regions of the container, is not necessarily strict. Even when the reflector protrudes or does not entirely cover various portions or regions, the effect of controlling the amount of heat released can still be achieved.

[0129] [Implementation Method 2]

[0130] use Figure 6 The structure of this embodiment is described. The structure other than the reflector is the same as that of Embodiment 1. The reflector included in the heating device 245 of this embodiment is an outer reflector 248b (outer heat reflecting member) disposed outside the heating line, that is, on the side opposite to the container across the heating line.

[0131] Figure 6 (a) is the first installation example of this embodiment. The outer reflector 248b is positioned outside the first portion 246b1 of the lower heater, that is, on the side opposite the container 244 across the first portion 246b1. As a result, heat dissipated outward from the first portion 246b1 is reflected by the outer reflector 248b, increasing the amount of heat incident on the first region 244b1 of the lower heater. It should be noted that, strictly speaking, a portion of the heat dissipated outward from the first portion 246b1 is absorbed by the outer reflector 248b and radiated toward the first region 244b1 of the lower heater, but reflection can also be understood to include this aspect. This embodiment is characterized by the placement of the outer reflector, which increases the radiation heat transfer rate between the first portion 246b1 of the lower heater and the first region 244b1 compared to the radiation heat transfer rate between the second portion 246b2 of the lower heater and the second region 244b2.

[0132] Figure 6 (b) is the second installation example of this embodiment. Figure 6 (a) In addition to the identical outer reflector (first outer reflector 248b1: first outer heat reflecting component), a second outer reflector 248b2 (second outer heat reflecting component) is also provided. The second outer reflector 248b2 is arranged to correspond to the entire lower heater 246b. As a result, when comparing the first region 244b1 with the second region 244b2, the amount of heat incident per unit area on the first region 244b1 is greater. It should be noted that the materials, structures, and processing methods of the first and second outer reflectors 248b1, 248b2 may be the same or different.

[0133] Figure 6(c) is a third installation example of this embodiment. The outer reflector 248b in this figure includes a first reflective portion 248b3 corresponding to the first portion 246b1 of the lower heater and a second reflective portion 248b4 facing the second portion 246b2. The first reflective portion 248a3 has a higher thermal reflectivity per unit area than the second reflective portion 248a4. This difference in reflectivity can be achieved by varying the material, surface finishing method, color, presence of holes, thickness, and other characteristics of each reflective portion.

[0134] According to this embodiment, the amount of heat incident on the second region 244b2 of the lower region 244b, which is closer to the upper region 244a, is smaller than the amount of heat incident on the first region 244b1. As a result, in a device with a dual-heater structure, excessive heating of the uppermost portion of the container 244 and sudden boiling of the evaporation material 242 can be suppressed with a simple structure, thereby achieving good film formation.

[0135] It should be noted that the relative orientation of the reflector and the heater components in the height direction is not necessarily strict. Even if the reflector protrudes or does not cover the entire portion, the effect of heat control on the released heat can be achieved.

[0136] [Implementation Method 3]

[0137] use Figure 7 The structure of this embodiment is described. It should be noted that, in the figure, the structure other than the container 244 and the heater 246 is omitted for simplicity. In this figure, the power of the upper heater 246a is fixed, and the power of the lower heater 246b is variable. In addition, in this figure, the lower heater 246b is used as Figure 5 Although the structure of (a) is not used, any structure described in Embodiments 1 and 2 may be used.

[0138] In this embodiment, the amount of heat radiated not only by lower heater 246b but also by upper heater 246a is varied in the height direction. In this figure, the side of upper heater 246a closer to the opening is defined as third portion 246a1, and the side closer to lower heater 246b is defined as fourth portion 246a2. An upper inner reflector 248c is positioned between fourth portion 246a2 and container 244. As a result, as indicated by the dotted arrow, the heat generated by third portion 246a1 is greater than the heat generated by fourth portion 246a2, which is shielded by the reflector.

[0139] According to this embodiment, the temperature at a position closer to the opening in the upper region 244a is increased, so that near the opening (near the nozzle if there is a nozzle), the effect of preventing the deposition material from adhering can be obtained. It should be noted that, here, a reflector is provided between the fourth portion 246a2 and the container 244, but various reflector configurations can be performed in the same manner as in embodiments 1 and 2. In addition, the density, number of turns, thickness (wire diameter), resistivity, etc. of the heating wires can also be changed in the upper heater 246a. That is, the heating wires of the fourth portion 246a2 can be made sparse, thicker, or the resistance can be reduced. Alternatively, the number of turns of the heating wires of the third portion 246a1 can also be increased.

[0140] The above-described embodiments can be combined with each other to the extent possible. For example, in Embodiments 1 and 2, various methods for installing the reflector are described. However, these methods are not exclusive and can be combined. Furthermore, as long as the objectives of the present invention can be achieved, any combination of the various reflector structures described in Embodiments 1 and 2 and the various structures of the upper heater 246a described in Embodiment 3 can be used. By combining multiple structures, a more efficient temperature relationship between the first and second regions can be established.

[0141] <Implementation Method 4>

[0142] <Specific Example of the Method for Manufacturing an Organic Electronic Device>

[0143] In this embodiment, an example of a method for manufacturing an organic electronic device using a vapor deposition apparatus (film-forming apparatus) equipped with an evaporation source device is described. The structure and manufacturing method of an organic EL display device are described below as an example of an organic electronic device. First, the manufactured organic EL display device is described. Figure 8 (a) is an overall view of the organic EL display device 60, Figure 8 (b) shows a cross-sectional structure of one pixel. As the evaporation source device 240 included in the film forming apparatus, the device described in any one of the above-mentioned embodiments is used.

[0144] like Figure 8As shown in (a), in the display area 61 of the organic EL display device 60, a plurality of pixels 62 each having a plurality of light-emitting elements are arranged in a matrix. Each light-emitting element has a structure having an organic layer sandwiched by a pair of electrodes. It should be noted that the pixel referred to here refers to the smallest unit that can display the desired color in the display area 61. In the case of the organic EL display device of this figure, the pixel 62 is formed by a combination of a first light-emitting element 62R, a second light-emitting element 62G, and a third light-emitting element 62B that emit light different from each other. The pixel 62 is mostly composed of a combination of a red light-emitting element, a green light-emitting element, and a blue light-emitting element, but can also be a combination of a yellow light-emitting element, a cyan light-emitting element, and a white light-emitting element, as long as it is at least one color, and is not particularly limited.

[0145] Figure 8 (b) Yes Figure 8 (a) is a partial cross-sectional view taken along line AB. Pixel 62 includes an organic EL element comprising a first electrode (anode) 64, a hole transport layer 65, one of light-emitting layers 66R, 66G, and 66B, an electron transport layer 67, and a second electrode (cathode) 68 on a substrate 63 as a vapor-deposited body. The hole transport layer 65, the light-emitting layers 66R, 66G, and 66B, and the electron transport layer 67 correspond to organic layers. In this embodiment, the light-emitting layer 66R is an organic EL layer that emits red light, the light-emitting layer 66G is an organic EL layer that emits green light, and the light-emitting layer 66B is an organic EL layer that emits blue light.

[0146] The light-emitting layers 66R, 66G, and 66B are formed into patterns corresponding to light-emitting elements (sometimes referred to as organic EL elements) that emit red light, green light, and blue light, respectively. In addition, the first electrode 64 is formed separately for each light-emitting element. The hole transport layer 65, the electron transport layer 67, and the second electrode 68 can be formed in common with the plurality of light-emitting elements 62R, 62G, and 62B, or can be formed for each light-emitting element. It should be noted that in order to prevent the first electrode 64 and the second electrode 68 from short-circuiting due to foreign matter, an insulating layer 69 is provided between the first electrode 64. In addition, since the organic EL layer will deteriorate due to moisture and oxygen, a protective layer 70 is provided to protect the organic EL element from moisture and oxygen corrosion.

[0147] Next, an example of a method for manufacturing an organic EL display device as an electronic device will be described in detail: First, a substrate 63 having a circuit (not shown) for driving the organic EL display device and a first electrode 64 formed thereon is prepared.

[0148] Next, an acrylic resin is formed by spin coating on the substrate 63 having the first electrode 64 formed thereon, and the acrylic resin is patterned by photolithography to form an opening in the portion where the first electrode 64 is formed, thereby forming an insulating layer 69. This opening corresponds to the light emitting region where the light emitting element actually emits light.

[0149] Next, the substrate 63 patterned with the insulating layer 69 is fed into the first film forming device, the substrate is held by the substrate holding unit, and the hole transport layer 65 is formed as a common layer on the first electrode 64 in the display area. The hole transport layer 65 is formed by vacuum evaporation. In fact, the hole transport layer 65 is formed to a size larger than the display area 61, so a high-precision mask is not required. Here, the film forming device used in the film forming in this step and the film forming of the following layers has a heating device (evaporation source device, film forming device) described in any one of the above embodiments. Therefore, sudden boiling, overheating, adhesion of the evaporation material, etc. during film formation are suppressed.

[0150] Next, the substrate 63, on which the hole transport layer 65 has been formed, is transported to the second film-forming apparatus and held by a substrate holding unit. Alignment between the substrate and the mask is performed, and the substrate is placed on the mask. A red-emitting layer 66R is formed on the portion of the substrate 63 where the red-emitting element is located. This example allows for good alignment between the mask and substrate, enabling high-precision film formation.

[0151] Similar to the film formation of the light-emitting layer 66R, the third film-forming apparatus forms the light-emitting layer 66G, which emits green light, and the fourth film-forming apparatus forms the light-emitting layer 66B, which emits blue light. After the film formation of the light-emitting layers 66R, 66G, and 66B is completed, the fifth film-forming apparatus forms the electron transport layer 67 over the entire display area 61. The electron transport layer 65 is formed as a common layer for the three color light-emitting layers 66R, 66G, and 66B.

[0152] The substrate formed up to the electron transport layer 65 is moved to a sputtering device to form a second electrode 68 , and then moved to a plasma CVD device to form a protective layer 70 , thereby completing the organic EL display device 60 .

[0153] From the time the substrate 63, patterned with the insulating layer 69, is transported into the film-forming apparatus until the formation of the protective layer 70 is completed, exposure to an environment containing moisture and oxygen may cause degradation of the light-emitting layer made of the organic EL material. Therefore, in this example, the substrates are transported in and out of the film-forming apparatus in a vacuum environment or an inert gas atmosphere.

[0154] The organic EL display device obtained as described above forms a light-emitting layer with high precision for each light-emitting element. Therefore, using the above-described manufacturing method can suppress the occurrence of defects in the organic EL display device caused by positional deviation of the light-emitting layer. According to the film-forming method or electronic device manufacturing method of this embodiment, the heating of the vapor deposition material is appropriately controlled, thereby achieving good vapor deposition.

Claims

1. A heating device for heating a container containing a vapor deposition material, characterized in that: The container includes an opening for releasing the heated vapor deposition material, a first region, and a second region that is a region farther from the opening than the first region. The heating device comprises: a first heater, the first heater heating the first area; a second heater that heats the second region; and a control unit that independently controls the first heater and the second heater, The second heater includes a first portion and a second portion, the second portion being closer to the first heater than the first portion. The control unit controls the first portion and the second portion integrally when controlling the second heater. The heating device further includes an inner heat reflecting member, which is disposed between the second portion and the container and faces the second portion, and blocks heat emitted from the second portion to the container. The heating device further includes a second inner heat reflecting member disposed between the first and second portions and the container and facing the first and second portions to block heat released from the first and second portions to the container.

2. The heating device according to claim 1, wherein The heating device further includes a second outer heat reflecting member disposed on the opposite side of the container across the first portion and the second portion.

3. The heating device according to claim 1, wherein The first heater includes a third portion and a fourth portion, wherein the third portion is disposed closer to the opening than the fourth portion. The amount of heat incident on the region of the container facing the first portion is greater than the amount of heat incident on the region of the container facing the second portion. The amount of heat incident on the region of the container facing the third portion is greater than the amount of heat incident on the region of the container facing the fourth portion.

4. The heating device according to claim 1, wherein The control unit controls so that the amount of heat generated by the second heater increases as the amount of the vapor deposition material contained in the container decreases due to evaporation.

5. The heating device according to claim 4, characterized in that The control unit performs control so that the amount of heat generated by the first heater is constant.

6. The heating device according to any one of claims 1 to 5, characterized in that The control unit controls the first heater and the second heater so that there is no portion where the temperature drops from the bottom portion toward the opening of the container.

7. An evaporation source device comprising a heating device and a container for accommodating an evaporation material, characterized in that: The heating device is the heating device according to any one of claims 1 to 6.

8. A film forming apparatus comprising: a chamber for accommodating a substrate as a vapor-deposited object; and an evaporation source device for releasing a vapor deposition material onto the substrate through a mask to form a film, characterized in that: The evaporation source device is the evaporation source device according to claim 7.

9. A film forming method for forming a film on a substrate as a vapor-deposited object using a vapor deposition material, characterized in that: The film forming method includes the step of heating and evaporating a vapor deposition material contained in a container using the heating device according to any one of claims 1 to 6.

10. A method for manufacturing an electronic device, characterized in that: An electronic device is manufactured using the film forming method according to claim 9.

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