Evaporation crucible and evaporation device

Abstract

The present invention provides a evaporation crucible and a evaporation device capable of suppressing adhesion of evaporation materials. A evaporation crucible is characterized in that it comprises: a first crucible; and a second crucible disposed inside the first crucible and accommodating the evaporation material, wherein the thermal conductivity of the material of the second crucible is greater than that of the material of the first crucible. A evaporation crucible is characterized in that it comprises: a first crucible; and a second crucible disposed inside the first crucible and accommodating the evaporation material, wherein the material of the second crucible is any one of molybdenum, tantalum, and tungsten.

Description

Technical Field

[0001] The present invention relates to a crucible for vapor deposition and a vapor deposition device. Background Art

[0002] One method for manufacturing organic EL light-emitting elements used in organic EL displays and other devices involves vapor deposition, which involves sublimating a deposition material and depositing it onto a substrate to form a thin film, such as a light-emitting layer or a metal layer. A vapor deposition apparatus for forming a film on a substrate using the vapor deposition method comprises a substrate holder that holds the substrate, a crucible that holds the deposition material, and a heater that heats the crucible. The crucible has an opening at the top. The deposition material within the crucible, which is located below the substrate holder and heated by the heater, sublimates, forming a thin film on the surface of the substrate facing the crucible opening.

[0003] Patent Document 1 discloses a double-layer crucible composed of two different materials. The crucible includes an outer crucible made of a material with high thermal conductivity and an inner crucible, located inside the outer crucible and made of a material with high infrared emissivity. A heating element provided in the outer crucible heats a deposition material contained in the inner crucible, causing the deposition material to sublime.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2018-104804 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] After the substrate is subjected to film-forming treatment by evaporation, the evaporation material remaining in the crucible is removed from the crucible, and a new evaporation material is put into the crucible, thereby preparing for the next film-forming treatment. However, the evaporation material sometimes remains in a manner such as adhering to the inner wall surface of the crucible. It is speculated that this is because a portion of the evaporation material heated during the film-forming treatment melts, solidifies during the cooling process, and adheres to the inner wall surface of the crucible. Since the adhered evaporation material cannot be easily removed from the crucible, it is necessary to heat the crucible again to sublime it and remove it from the crucible. Therefore, there is a problem that the replacement of the evaporation material after the film-forming treatment and the cleaning of the crucible take time and effort.

[0009] An object of the present invention is to provide a vapor deposition crucible and a vapor deposition apparatus capable of suppressing adhesion of a vapor deposition material.

[0010] Solutions to Problems

[0011] The present invention relates to a crucible for evaporation, characterized in that:

[0012] The evaporation crucible has:

[0013] a first crucible; and

[0014] The second crucible is arranged inside the first crucible and contains the evaporation material.

[0015] The thermal conductivity of the material of the second crucible is greater than the thermal conductivity of the material of the first crucible.

[0016] The present invention relates to a crucible for evaporation, characterized in that:

[0017] The evaporation crucible has:

[0018] a first crucible; and

[0019] The second crucible is arranged inside the first crucible and contains the evaporation material.

[0020] The material of the second crucible is any one of molybdenum, tantalum and tungsten.

[0021] Effects of the Invention

[0022] According to the present invention, a vapor deposition crucible and a vapor deposition apparatus capable of suppressing adhesion of a vapor deposition material can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic cross-sectional view showing a vapor deposition apparatus including the vapor deposition crucible of Example 1.

[0024] Figure 2 These are a perspective view and a cross-sectional view of the vapor deposition crucible of Example 1.

[0025] Figure 3 This is a diagram schematically showing how the controller in Example 1 controls the heater.

[0026] Figure 4 This is a schematic cross-sectional view showing a vapor deposition apparatus including the vapor deposition crucible of Example 2.

[0027] Figure 5 This is a schematic cross-sectional view showing a vapor deposition apparatus including the vapor deposition crucible of Example 3.

[0028] Figure 6 This is a schematic cross-sectional view showing a vapor deposition apparatus including the vapor deposition crucible of Example 4.

[0029] Figure 7 This is a diagram showing the structure of an organic EL display device of Example 5.

[0030] Description of Reference Signs

[0031] 1: Evaporation device; 20: Crucible; 21: First crucible; 22: Second crucible; 50: Heater; 70: Evaporation material. DETAILED DESCRIPTION

[0032] Hereinafter, with reference to the accompanying drawings, the method for implementing the present invention will be exemplified. However, the size, material, shape, relative arrangement, etc. of the constituent parts shall not be limited thereto unless otherwise specified. In the following description, unless otherwise specified, the terms "up" and "down" respectively indicate that the vertical direction is upward and downward, and the device is used in a state where it is set on a horizontal plane. In the vapor deposition device, the film forming surface of the substrate held by the substrate holder is parallel to the horizontal plane in an ideal state without considering the deflection of the substrate. In addition, terms indicating geometric shapes or relationships such as parallel, vertical, circular, and straight lines are not limited to mathematically strict shapes or relationships caused by manufacturing tolerances, etc., but also include deviations therefrom.

[0033] (Example 1)

[0034] Figure 1 1 is a schematic cross-sectional view showing a vapor deposition apparatus including a vapor deposition crucible (hereinafter referred to as simply a crucible) according to Example 1 of the present invention. Figure 2 These are a perspective view and a cross-sectional view of the crucible of Example 1.

[0035] The vapor deposition apparatus 1 of Example 1 is an apparatus for forming a functional film for an organic EL element used in a display device, lighting device, or the like on a film formation target surface 41 of a substrate 40 by vapor deposition. The vapor deposition apparatus 1 includes a vacuum chamber 10, a substrate holder 30 disposed within the vacuum chamber 10 and holding the substrate 40, a crucible 20 for storing a vapor deposition material 70, a heater 50 for heating the crucible 20, and a controller 60 for controlling the operation of the heater 50.

[0036] The evaporation apparatus 1 may also include a mechanism for moving the crucible 20 and substrate holder 30 to perform film formation while relatively moving the crucible 20 and substrate 40, a transport mechanism for loading and unloading the substrate 40 before and after film formation from outside the vacuum chamber 10, and a replacement mechanism for removing the evaporation material 70 remaining in the crucible 20 after film formation and replacing it with fresh evaporation material 70. However, these are not essential to the description of the present invention and are therefore omitted in detail. Furthermore, film formation in the evaporation apparatus 1 is performed with a mask having openings corresponding to the film formation pattern attached to the film formation target surface 41 of the substrate 40. An organic EL device manufacturing apparatus using the evaporation apparatus 1 performs mask alignment and mask attachment in an apparatus separate from the evaporation apparatus 1, and then loads the substrate 40 with the mask attached into the evaporation apparatus 1 for film formation. Furthermore, the crucible and evaporation apparatus of the present invention are applicable to any manufacturing apparatus that forms films on substrates using evaporation.

[0037] The crucible 20 includes a first crucible 21 and a second crucible 22 disposed inside the first crucible 21. The first crucible 21 and the second crucible 22 are cylindrical containers with bottoms and are open upward. The inner diameter of the first crucible 21 is slightly larger than the outer diameter of the second crucible 22, and the gap between the inner wall surface of the first crucible 21 and the outer wall surface of the second crucible 22 is 0.1 to 0.3 mm. In other words, the difference between the inner diameter of the first crucible 21 and the outer diameter of the second crucible 22 is greater than 0.1 mm and less than 0.6 mm. Thus, the second crucible 22 can be loaded and unloaded relative to the first crucible 21. The thickness of the side wall of the second crucible 22 is greater than 0.1 mm and less than 0.5 mm. Since the thickness of the side wall is less than 0.5 mm, it is thin enough. Therefore, even with the double-layer structure of the first crucible 21 and the second crucible 22, the filling amount of the evaporation material 70 is less affected, and a sufficient filling amount can be ensured. Furthermore, since the thickness of the side wall portion is 0.1 mm or more, the second crucible 22 can maintain its shape with sufficient strength, and good operability when attaching and detaching the second crucible 22 to the first crucible 21 can be ensured.

[0038] The first crucible 21 and the second crucible 22 contact at their bottoms. The height H2 of the outer wall of the second crucible 22 is lower than the height H1 of the inner wall of the first crucible 21. In Example 1, H2 is less than two-thirds of H1. The height H1 of the inner wall of the first crucible 21 is, for example, the distance from the bottom of the first crucible 21 to the upper surface defining the interior space of the crucible 20. In this embodiment, the upper surface is formed by the cover 25, described below. In this case, a portion of the inner wall of the first crucible 21 may also be formed by a member separate from the first crucible 21, namely the cover 25. For convenience, the portion formed by a member separate from the first crucible 21 may also be considered as a portion of the inner wall of the first crucible 21. Alternatively, the height H1 of the inner wall of the first crucible 21 may be the distance from the bottom of the first crucible 21 to the boundary between the first crucible 21 and the member forming the upper surface. The height H2 of the outer wall of the second crucible 22 is, for example, the distance from the bottom to the upper end of the outer surface of the second crucible 22. The second crucible 22 is made of a material having a higher thermal conductivity than the material of the first crucible 21. In Example 1, the material of the first crucible 21 is titanium (Ti), and the material of the second crucible 22 is molybdenum (Mo).

[0039] The crucible 20 includes a lid 25 and a plate 23 disposed below the lid 25. A nozzle 26 for discharging a vapor deposition material is disposed near the center of the lid 25. The lid 25 includes a first wall 251 that forms the nozzle 26, an upper surface 252, and a second wall 253 having a larger outer diameter than the first wall 251 and forming a connection with the first crucible 21. The thickness of the first wall 251 and the thickness of the upper surface 252 are both greater than the thickness of the second wall 253. The lid 25 also includes a cover member 254 that covers the periphery of the first wall 251 and the upper portion of the upper surface 252. A plurality of openings 24 for passage of the vapor deposition material are disposed near the periphery of the plate 23. The plate 23 is disposed on the inner wall surface of the first crucible 21, away from the upper end of the second crucible 22. The plate 23 is supported by the first crucible 21 at a position away from the upper end of the second crucible 22. Plate 23 suppresses sudden boiling of deposition material 70. An annular sealing member 255 is disposed at the junction of lid 25 and first crucible 21. Sealing member 255 is made of metal, preferably the same material as first crucible 21 (titanium in this embodiment).

[0040] The vapor deposition material 70 is accommodated in the second crucible 22. The vapor deposition material 70 is a metal material for forming a metal film on the film formation target surface 41 of the substrate 40, and examples thereof include silver (Ag), magnesium (Mg), ytterbium (Yb), and lithium fluoride (LiF).

[0041] The heater 50 is provided around the first crucible 21. The heater 50 includes an upper heater 51 disposed above the upper end of the second crucible 22 and a lower heater 52 disposed below the upper end of the second crucible 22. The upper heater 51 and the lower heater 52 can be independently controlled by the controller 60.

[0042] Heat applied to the first crucible 21 by the heater 50 is transferred through the first crucible 21 to the second crucible 22, and further from the second crucible 22 to the evaporation material 70. The evaporation material 70 is heated and vaporized by the heat transferred from the second crucible 22, and then released upward from the crucible 20 through the opening 24 of the plate 23 and the nozzle 26 of the lid 25. The vapor of the evaporation material 70 released from the crucible 20 adheres to the film formation surface 41 of the substrate 40 facing the nozzle 26 of the lid 25. As a result, a thin film is formed on the substrate 40.

[0043] Figure 3 Schematically shows how the controller 60 controls the heater 50 . Figure 3 (A) shows the change in temperature with time. Curve A shows the change in temperature of the plate portion 23 (upper heater 51 ), and curve B shows the change in temperature of the vapor deposition material 70 (lower heater 52 ). Figure 3(B) shows the temporal change of the control value output by the controller 60 to the heater 50 , curve C shows the control value for the upper heater 51 , and curve D shows the control value for the lower heater 52 . Figure 3 (C) shows the evaporation rate of the evaporation material 70 from the crucible 20 .

[0044] When the film forming process of the evaporation device 1 starts, as shown in FIG. Figure 3 As shown in (B), the controller 60 starts heating by the upper heater 51 at time t1 and starts heating by the lower heater 52 at time t2 later than time t1. In this way, by delaying the start time of heating by the lower heater 52 relative to the start time of heating by the upper heater 51, as shown in FIG. Figure 3 As shown in (A), the temperature of the plate portion 23 located near the upper heater 51 is first increased, and then the temperature of the evaporation material 70 located near the lower heater 52 is increased. Then, at time t3 when the evaporation material 70 begins to sublime, the temperature of the plate portion 23 reaches the target temperature. The target temperature of the plate portion 23 is higher than the freezing point of the evaporation material 70. This prevents the sublimated evaporation material 70 from solidifying on the plate portion 23.

[0045] Because the first crucible 21 is made of titanium, a material with low thermal conductivity, heat generated by the upper heater 51 is difficult to transfer to the lower portion of the first crucible 21, where the second crucible 22 is located. Furthermore, because the height of the second crucible 22 is less than two-thirds of the height of the first crucible 21, the second crucible 22, with its high thermal conductivity, is located away from the upper heater 51 and the plate 23. This prevents the deposition material 70 from starting to sublime earlier than expected due to radiant heat from the upper heater 51 and the plate 23, which begin heating earlier than the lower heater 52. If the deposition material 70 starts to sublime earlier than expected, the sublimated deposition material 70 may solidify on the plate 23, where the temperature has not yet risen sufficiently. However, the deposition apparatus 1 of Example 1 prevents the deposition material 70 from adhering to the plate 23.

[0046] Because the second crucible 22 is made of molybdenum, a material with high thermal conductivity, the heat generated by the lower heater 52 is evenly transferred to the deposition material 70 in both time and space, enabling the deposition material 70 to sublime effectively. This prevents the deposition material 70, heated during film formation, from partially melting and solidifying during cooling, thereby adhering to the inner wall of the second crucible 22. Furthermore, it prevents the deposition material 70 from remaining adhering to the inner wall of the second crucible 22 after film formation. This makes it easy to remove the deposition material 70 from the second crucible 22 after film formation, reducing the time and effort required to replace the deposition material 70 and clean the crucible 20.

[0047] Since the sidewall of the second crucible 22 is sufficiently thin, being 0.5 mm or less, the heat from the lower heater 52 conducted to the second crucible 22 via the first crucible 21 is efficiently conducted as radiant heat to the evaporation material 70. Consequently, even when a heater is provided outside the double-layered crucible, sufficient temperature controllability can be achieved.

[0048] After the film formation process on the substrate 40 is completed, the lid 25 and plate 23 of the crucible 20 are removed, and the second crucible 22 is removed from the first crucible 21. Even if the evaporation material 70 remains in the removed second crucible 22, it can be easily removed because the evaporation material 70 does not adhere to the inner wall surface of the second crucible 22. Therefore, the process of removing the remaining evaporation material 70 from the second crucible 22 and adding new evaporation material 70 can be efficiently performed in preparation for the next film formation process.

[0049] As described above, according to the crucible 20 and the evaporation device 1 of Example 1, the adhesion of the evaporation material 70 can be suppressed. In addition, it is preferable that the difference in thermal conductivity between the materials of the first crucible 21 and the second crucible 22 is large. The thermal conductivity of titanium as the material of the first crucible 21 is 17W / mK, and the thermal conductivity of molybdenum as the material of the second crucible 22 is 147W / mK, which is a sufficiently large difference. In addition, as the material of the second crucible 22, tantalum (Ta, thermal conductivity 57.5W / mK) or tungsten (W, thermal conductivity 198W / mK) can also be used. In addition, when the material of the second crucible 22 is molybdenum, tantalum or tungsten, the material of the first crucible 21 is not limited to titanium. In addition, the materials of the first crucible 21 and the second crucible 22 are not limited to the example of Example 1, as long as the thermal conductivity of the material of the second crucible 22 is greater than the thermal conductivity of the material of the first crucible 21.

[0050] (Example 2)

[0051] A second embodiment of the present invention will be described. Components common to those in the first embodiment are given the same names and reference numerals as in the first embodiment, and detailed descriptions thereof will be omitted. Figure 4This is a schematic cross-sectional view of a vapor deposition apparatus including a crucible according to Example 2. The heater 500 included in the crucible 200 of Example 2 heats the entire upper portion of the first crucible 21, where the second crucible 22 is not located, and the lower portion where the second crucible 22 is located. In the heater 500, the heating power of the upper heating section 510, which heats the portion of the first crucible 21 located above the upper end of the second crucible 22, is greater than the heating power of the lower heating section 520, which heats the portion of the first crucible 21 located below the upper end of the second crucible 22. When the heater 500 utilizes resistance heating, the heating power can be varied by making the resistance value of the upper heating section 510 greater than that of the lower heating section 520. When the heater 500 utilizes induction heating, the heating power can be varied by making the number of coil turns in the upper heating section 510 greater than that in the lower heating section 520. Furthermore, the configuration for varying the heating power is not limited to this example.

[0052] The controller 60 controls the operation of the heater 500. When the controller 60 starts heating with the heater 500, the upper heating unit 510 and the lower heating unit 520 start to heat up at the same time. However, since the heating power of the upper heating unit 510 is large, the temperature of the upper portion of the first crucible 21 rises faster than that of the lower portion. Therefore, the temperature of the upper portion of the first crucible 21 rises faster than that of the lower portion. Figure 3 Similarly, when the evaporation material 70 begins to sublime, the temperature of the plate portion 23 is sufficiently high. Therefore, the sublimated evaporation material 70 is prevented from solidifying on the plate portion 23. Furthermore, although the heating power of the lower heating unit 520 is low, the high thermal conductivity of the material of the second crucible 22 allows for uniform heating of the evaporation material 70, preventing partial melting and adhesion to the inner wall of the second crucible 22.

[0053] As described above, according to the crucible 200 and the vapor deposition apparatus 1 of the second embodiment, adhesion of the vapor deposition material 70 can be suppressed.

[0054] (Example 3)

[0055] A third embodiment of the present invention will be described. Components common to those in the first embodiment are given the same names and reference numerals as in the first embodiment, and detailed descriptions thereof will be omitted. Figure 5 This is a schematic cross-sectional view of a vapor deposition apparatus including a crucible according to Example 3. The crucible 210 according to Example 3 does not include the plate portion 23 of Examples 1 and 2. The heater 511 included in the crucible 210 according to Example 3 heats the entirety of the upper portion of the first crucible 21, where the second crucible 22 is not located, and the lower portion where the second crucible 22 is located. The heater 511 is configured to heat the lid 25 above the first crucible 21.

[0056] The controller 60 controls the operation of the heater 511. When the controller 60 starts heating by the heater 511, the temperature of the lid 25 starts to rise first. Since the height of the second crucible 22 is less than 2 / 3 of the height of the first crucible 21, the second crucible 22 is away from the lid 25 and is not easily affected by the radiant heat from the lid 25. In addition, since the thermal conductivity of the material of the first crucible 21 is low, the heat from the lid 25 is difficult to transfer to the second crucible 22. Therefore, the second crucible 22 is not as hot as the first crucible 21. Figure 3 Similarly, the temperature of the lid 25 is sufficiently high when the evaporation material 70 begins to sublime. Therefore, the sublimated evaporation material 70 is prevented from solidifying on the lid 25. Furthermore, since the material of the second crucible 22 has high thermal conductivity, the evaporation material 70 can be heated uniformly, preventing it from partially melting and adhering to the inner wall surface of the second crucible 22.

[0057] As described above, according to the crucible 210 and the vapor deposition apparatus 1 of the third embodiment, adhesion of the vapor deposition material 70 can be suppressed.

[0058] (Example 4)

[0059] A fourth embodiment of the present invention will be described. Components common to those in the first embodiment are given the same names and reference numerals as in the first embodiment, and detailed descriptions thereof will be omitted. Figure 6 This is a schematic cross-sectional view of a vapor deposition apparatus including a crucible according to Example 4. The crucible 211 of Example 4 does not include the plate portion 23 of Examples 1 and 2. Furthermore, the height of the second crucible 220 is the same as that of the first crucible 21. As in Example 3, the heater 511 is configured to heat the entire first crucible 21 and also heat the lid 25 above it.

[0060] The controller 60 controls the operation of the heater 511. When the controller 60 starts heating with the heater 511, the temperature of the lid 25 begins to rise. Furthermore, the heat from the heater 511 is transferred to the second crucible 22 via the first crucible 21, which has low thermal conductivity. Radiation heat from the second crucible 22 is then transferred to the evaporation material 70. Because the material of the second crucible 22 has high thermal conductivity, the evaporation material 70 is heated uniformly, preventing partial melting and adhesion to the inner wall of the second crucible 22.

[0061] As described above, according to the crucible 211 and the vapor deposition apparatus 1 of the fourth embodiment, adhesion of the vapor deposition material 70 can be suppressed.

[0062] (other)

[0063] As long as the thermal conductivity of the second crucible material is greater than that of the first crucible material, or the second crucible material is any one of molybdenum, tantalum, and tungsten, a structure formed by appropriately combining the various characteristic elements described in each embodiment is included in the present invention. For example, in Example 1, a structure in which the second crucible can be attached and detached relative to the first crucible is illustrated, but a structure in which the second crucible is fixed to the first crucible is also possible. In addition, in Examples 1 to 3, a structure in which the height of the second crucible is less than 2 / 3 of the height of the first crucible is illustrated, but the height of the second crucible is appropriately designed based on the shape, performance, and material of the plate, lid, first crucible, second crucible, heater, etc., to meet the condition that the evaporation material does not begin to sublime before the plate or lid is heated to above the freezing point of the evaporation material due to radiant heat from the plate or lid. In addition, in a structure with multiple independently controllable heaters as in Example 1, the start time of heating of each heater can also be adjusted. In addition, a structure in which the thickness of the side wall of the second crucible is greater than 0.1 mm and less than 0.5 mm is illustrated, but the thickness of the side wall of the second crucible can be appropriately designed according to various conditions such as the shapes of the first crucible and the second crucible, the size of the substrate of the film formation object, the physical properties of the vapor deposition material, and whether the second crucible can be loaded and unloaded.

[0064] (Example 5)

[0065] A method for manufacturing an electronic device by forming an organic film on a substrate using a film forming device of the evaporation device of the above embodiment is described. Here, a method for manufacturing an organic EL element for an organic EL display as an electronic device is described as an example. In addition, the electronic device is not limited to this. For example, the present invention can also be applied to the manufacture of thin-film solar cells and organic CMOS image sensors. In the manufacturing method of the electronic device of Example 5, there is a process of forming an organic film on the substrate 5 using the film forming device of the above embodiment. In addition, there is a process of forming a metal film or a metal oxide film after forming the organic film on the substrate 5. The structure of the organic EL display device 600 using the organic EL element manufactured by such a process is described below.

[0066] Figure 7 (A) is an overall view of an organic EL display device 600. Figure 7 (B) shows the cross-sectional structure of one pixel of the organic EL display device 600. Figure 7As shown in (A), in the display area 61 of the organic EL display device 600, a plurality of pixels 62 having a plurality of light-emitting elements are arranged in a matrix. Each light-emitting element has a structure including an organic layer sandwiched between a pair of electrodes. In addition, the pixel referred to here refers to the minimum unit that can display the desired color in the display area 61. In the organic EL display device 600, the pixel 62 is composed of 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 of different colors. The first light-emitting element 62R, the second light-emitting element 62G and the third light-emitting element 62B are red light-emitting elements, green light-emitting elements and blue light-emitting elements, respectively. In addition, the number of light-emitting elements and the combination of light-emitting colors of each pixel are not limited to this example. For example, it can be a combination of a yellow light-emitting element, a cyan light-emitting element and a white light-emitting element, or at least one color or more. In addition, each light-emitting element can also be composed of a plurality of light-emitting layers stacked on top of each other.

[0067] A pixel 62 may be formed by a plurality of light-emitting elements that emit the same color, and a color filter having different color conversion elements arranged in a manner corresponding to each light-emitting element may be used to enable one pixel 62 to display a desired color. For example, a pixel 62 may be formed by three white light-emitting elements, and a color filter having red, green, and blue color conversion elements arranged in a manner corresponding to each light-emitting element may be used. Alternatively, a pixel 62 may be formed by three blue light-emitting elements, and a color filter having red, green, and colorless color conversion elements arranged in a manner corresponding to each light-emitting element may be used. The number of light-emitting elements per pixel and the combination of light-emitting colors are not limited to these examples. In the latter case, by using a quantum dot color filter (QD-CF) using a quantum dot (QD: Quantum Dot) material as a material constituting the color filter, the display color gamut can be widened compared to an organic EL display device that does not use a quantum dot color filter.

[0068] Figure 7 (B) Yes Figure 7 (A) Schematic diagram of a partial cross section of line AB. The pixel 62 has an organic EL element having a first electrode (anode) 64, a hole transport layer 65, a light-emitting layer 66R, 66G or 66B, an electron transport layer 67, and a second electrode (cathode) 68 formed on a substrate 5. The hole transport layer 65, the light-emitting layers 66R, 66G, 66B and the electron transport layer 67 are organic layers. The light-emitting layer 66R is an organic EL layer that emits red, the light-emitting layer 66G is an organic EL layer that emits green, and the light-emitting layer 66B is an organic EL layer that emits blue. In addition, when a color filter or a quantum dot color filter is used, on the light emitting side of each light-emitting layer, that is, Figure 7 A color filter or a quantum dot filter is arranged on the upper or lower part of (B).

[0069] The light-emitting layers 66R, 66G, and 66B are light-emitting elements that emit red, green, and blue, respectively, or organic EL elements. The light-emitting layers 66R, 66G, and 66B are formed according to the arrangement pattern of the light-emitting elements 62R, 62G, and 62B. The first electrode 64 is formed for each light-emitting element and is separated from each other. The hole transport layer 65, the electron transport layer 67, and the second electrode 68 can be formed in a manner that is shared by multiple light-emitting elements 62R, 62G, and 62B, or they can be formed separately for each light-emitting element. 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. Because the organic EL layer degrades due to moisture or oxygen, a protective layer P is provided to protect the organic EL element from the effects of moisture and oxygen.

[0070] A method for manufacturing an organic EL display device as an electronic device will be described.

[0071] First, a circuit (not shown) for driving the organic EL display device and the substrate 5 on which the first electrode 64 is formed are prepared.

[0072] Next, a resin layer such as acrylic resin or polyimide is formed by spin coating on the substrate 5 having the first electrode 64 formed thereon. The resin layer is then 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.

[0073] Next, the substrate 5, with the insulating layer 69 patterned thereon, is loaded into the first film-forming apparatus. The substrate is held by a substrate holding unit, and a hole transport layer 65 is formed as a common layer above the first electrode 64 in the display area. The hole transport layer 65 is formed by vacuum evaporation. In practice, since the hole transport layer 65 is formed larger than the display area 61, a high-precision mask is not required. The film-forming apparatus used for film formation in this step and for the subsequent layers is a film-forming apparatus using the evaporation apparatus described in any of the above-described embodiments.

[0074] Next, the substrate 5, having been formed with the hole transport layer 65, is loaded into the second film-forming apparatus and held by the substrate holding unit. The substrate 5 and the mask 6 are aligned, the substrate 5 is placed on the mask 6, and the red light-emitting layer 66R is formed on the portion of the substrate 5 where the red-emitting elements are located. By using the film-forming apparatus of Embodiment 2, the mask 6 and substrate 5 can be aligned with high precision, and the mask 6 and substrate 5 can be brought into close contact, enabling high-precision film formation.

[0075] Similar to the film formation of the light-emitting layer 66R, the green light-emitting layer 66G is formed using the third film-forming apparatus, and the blue light-emitting layer 66B is further formed using the fourth film-forming apparatus. After the film formation of the light-emitting layers 66R, 66G, and 66B is completed, the electron transport layer 67 is formed over the entire display area 61 using the fifth film-forming apparatus. The light-emitting layers 66R, 66G, and 66B can each be a single layer or a layer composed of multiple different layers. The electron transport layer 67 is formed as a layer common to the three color light-emitting layers 66R, 66G, and 66B. In Embodiment 2, the electron transport layer 67 and the light-emitting layers 66R, 66G, and 66B are formed by vacuum evaporation.

[0076] Next, a second electrode 68 is formed on the electron transport layer 67. The second electrode can be formed by vacuum deposition or sputtering. The substrate 5 with the second electrode 68 formed thereon is then moved to a sealing device, where a sealing step is performed to form a protective layer P using plasma CVD, completing the organic EL display device 600. While the protective layer P is formed using CVD, this is not limiting and can also be formed using ALD or inkjet.

[0077] From the time the substrate 5 with the patterned insulating layer 69 is loaded into the film forming apparatus until the formation of the protective layer P is completed, the substrate 5 is exposed to an atmosphere containing moisture or oxygen, which may degrade the light-emitting layer. In the second embodiment, the substrate 5 is loaded and unloaded between film forming apparatuses in a vacuum atmosphere or an inert gas atmosphere.

Claims

1. A crucible for evaporation, The evaporation crucible has: a first crucible; and The second crucible is arranged inside the first crucible and contains the evaporation material. The thermal conductivity of the material of the second crucible is greater than the thermal conductivity of the material of the first crucible, It is characterized by: The evaporation crucible includes a cover portion that covers the upper portion of the first crucible and has a nozzle for discharging the evaporation material. The cover portion includes: a first wall portion that constitutes the nozzle; an upper surface portion; and a second wall portion that has an outer circumference larger than that of the first wall portion and constitutes a connection portion connected to the first crucible. The thickness of the first wall portion and the thickness of the upper surface portion are respectively greater than the thickness of the second wall portion. The vapor deposition crucible further includes a plate portion, which is provided below the lid portion and has an opening for the vapor deposition material to pass through. The first crucible and the second crucible are in contact at the bottom, The height of the outer wall of the second crucible is lower than the height of the inner wall of the first crucible.

2. The evaporation crucible according to claim 1, wherein The material of the second crucible is any one of molybdenum, tantalum and tungsten.

3. The evaporation crucible according to claim 1 or 2, characterized in that: The material of the first crucible is titanium.

4. The evaporation crucible according to claim 1, wherein The height of the outer wall surface of the second crucible is less than or equal to 2 / 3 of the height of the inner wall surface of the first crucible.

5. The evaporation crucible according to any one of claims 1, 2, and 4, characterized in that: The thickness of the side wall of the second crucible is greater than or equal to 0.1 mm and less than or equal to 0.5 mm.

6. The evaporation crucible according to claim 1 or 2, characterized in that: The plate portion is provided on the inner wall surface of the first crucible at a position away from the upper end of the second crucible.

7. The evaporation crucible according to claim 1 or 2, characterized in that: The plate portion is supported by the first crucible at a position away from an upper end of the second crucible.

8. The evaporation crucible according to claim 1 or 2, characterized in that: The vapor deposition crucible further includes a cover member that covers the periphery of the first wall portion and the upper portion of the upper surface portion.

9. The evaporation crucible according to any one of claims 1, 2, and 4, characterized in that: The vapor deposition crucible further includes a heater provided around the first crucible.

10. The evaporation crucible according to claim 9, characterized in that The heater includes an upper heater disposed above the upper end of the second crucible and a lower heater disposed below the upper end of the second crucible. The upper heater and the lower heater are independently controlled.

11. The evaporation crucible according to claim 9, wherein The heater has a greater heating power for heating a portion of the first crucible above the upper end of the second crucible than for heating a portion of the first crucible below the upper end of the second crucible.

12. The evaporation crucible according to any one of claims 1, 2, 4, 10, and 11, wherein: A difference between an inner diameter of the first crucible and an outer diameter of the second crucible is 0.1 mm or more and 0.6 mm or less.

13. The crucible for vapor deposition according to any one of claims 1, 2, 4, 10, and 11, characterized in that: The second crucible is attachable to and detachable from the first crucible.

14. The evaporation crucible according to any one of claims 1, 2, 4, 10, and 11, wherein: The evaporation material is any one of silver, magnesium, ytterbium and lithium fluoride.

15. A vapor deposition device, characterized in that: The vapor deposition device comprises the vapor deposition crucible according to any one of claims 1 to 14, The vapor deposition apparatus vaporizes the vapor deposition material contained in the vapor deposition crucible to form a film on a substrate.

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