JP2020071916A - Manufacturing method for organic light emitting element - Google Patents

Abstract

To provide a manufacturing method capable of suppressing a decrease in life of an organic light emitting element.SOLUTION: A manufacturing method for an organic light emitting element that includes a plurality of layers is characterized to include the steps of: vapor-depositing a first layer among the plurality of organic layers on a substrate in a first chamber; and vapor-depositing a second layer and a third layer in a second chamber without carrying out the substrate from the second chamber, the third layer being made of a material different from the martial of the second layer.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an organic light emitting device, a manufacturing method thereof, and a manufacturing apparatus thereof.

  In recent years, development of organic light-emitting devices capable of coating film formation and low-temperature processes has been advanced.

  The organic light emitting device generally forms a laminated body made of a plurality of different organic materials. As a method for manufacturing the laminated body, there are a method of sequentially depositing each layer in one vacuum chamber, a method of independently providing a plurality of chambers and forming each layer in each chamber.

  For example, in the case of the former method, the material for each layer is set in the chamber, and the shutter for controlling the film formation on the film formation target and the shutter for controlling the supply of the vapor deposition source are opened and closed to sequentially form each layer. To do. In this case, a plurality of vapor deposition sources are heated at the same time. Therefore, during formation of the predetermined film, even if the non-predetermined evaporation source shutter is closed, the non-predetermined material may be mixed. In particular, when an electron-transporting material is mixed in the hole-transporting layer or a hole-transporting material is mixed in the electron-transporting layer (referred to as contamination here), an excited charge transfer complex called an exciplex is formed to form an organic light emitting device. The characteristics of are markedly reduced.

  On the other hand, according to the latter method, since each layer can be independently formed in each chamber, it is possible to prevent contamination during the film forming process. For example, Patent Document 1 discloses a cluster-type film forming apparatus in which a transfer chamber (core chamber) including a transfer arm and a plurality of film formation chambers (process chambers) radially arranged around the transfer chamber are connected to each other. It is disclosed.

JP, 2007-212186, A

  The number of layers of the organic light emitting element may increase as the function of the display device using the organic light emitting element increases. In the manufacturing method of Patent Document 1, since the film-forming target moves back and forth between the process chamber and the core chamber to form each layer, it takes a long time to convey the film. Further, depending on the material of the layer, if the residence time at the interface after film formation becomes long, the characteristics deteriorate due to the substance contained in the process chamber or the core chamber.

  In order to solve the above problems, the present invention is to provide a manufacturing process in which deterioration of the characteristics of the organic light emitting device is easily suppressed.

  A method of manufacturing an organic light emitting device according to the present invention comprises a step of depositing a first layer of the plurality of organic layers on a substrate in a first chamber, and a step of depositing a first layer of the plurality of organic layers in a second chamber. Depositing two layers and a third layer of a material different from the second layer of the plurality of organic layers without unloading the substrate from the second chamber.

  In the apparatus for manufacturing an organic light emitting device according to the present invention, the number of crucibles in the first chamber is different from the number of crucibles in the second chamber.

  The organic light-emitting element according to the present invention, in plan view, has an outer edge of a first layer of the plurality of organic layers and an outer edge of a second layer of the plurality of organic layers made of a material different from the first layer. And the outer edge of the second layer and the outer edge of the third layer made of a material different from that of the second layer coincide with the outer edge of the second layer.

  By applying the present invention, deterioration of the characteristics of the organic light emitting device can be easily prevented.

The figure which shows the structure of the manufacturing apparatus which concerns on 1st embodiment of this invention. The cross-sectional schematic diagram and plane schematic diagram which show the structure of the process chamber of the manufacturing apparatus which concerns on 1st embodiment of this invention. 1 is a schematic sectional view of an organic light emitting device according to a first embodiment of the present invention. 1 is a schematic plan view of a first layer, a second layer, and a third layer of an organic light emitting device according to a first embodiment of the present invention. The graph which shows the correlation of the life of each layer. The cross-sectional schematic diagram of the organic light emitting element concerning 2nd embodiment of this invention. The cross-sectional schematic diagram of the organic light emitting element concerning 3rd embodiment of this invention. The cross-sectional schematic diagram of the organic light emitting element concerning the 4th embodiment of this invention. The cross-sectional schematic diagram of the organic light emitting element concerning the 5th embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The dimensions of each part in the drawing are different from the actual ones. Further, well-known or publicly-known techniques in the technical field are applied to portions not particularly illustrated or described in the present specification.

<First embodiment>
FIG. 1 is a diagram showing the overall configuration of a manufacturing apparatus 1000 according to the first embodiment of the present invention. FIG. 2A is a schematic cross-sectional view showing the configuration of each process chamber Px (x indicates a process chamber unit, where x = 1 to 3). 2B is a schematic plan view showing the structure of the process chamber Px. FIG. 3 is an organic light emitting device 100 including a plurality of organic layers according to the present embodiment. A method for manufacturing the organic light emitting device 100 will be described with reference to FIGS. 1, 2A, and 2B.

(Preparation)
Before the wafer W is loaded into the manufacturing apparatus 1000, the process chambers P1 to P3 are prepared for film formation. The process chambers P1 to P3 are evacuated by a cryopump (or turbo molecular pump) P and are maintained in a high vacuum of 1.0 × 10 ⁻³ Pa <vacuum degree <1.0 × 10 ⁻⁸ Pa.

  Next, preparation for forming a film of the material O11 in the process chamber Px will be described. First, the material O11 of a predetermined layer is placed in the crucible CR11 placed in the heating source SC11. The heating source SC11 is a heating source for heating the crucible CR11. Then, when the process chamber reaches a predetermined vacuum degree, the heating source SC11 is heated. As a result, the crucible CR11 arranged in the heating source SC11 is heated. The temperature of the heating source SC11 is monitored by a temperature sensor. After reaching the predetermined temperature, the vapor deposition source shutter SS11 is opened, and the vapor deposition rate of the material O11 is monitored by the crystal oscillator XT11. The heating source SC11 is controlled by the temperature control device so as to have a predetermined vapor deposition rate.

  In FIG. 2A, two crucibles and two heat sources are shown. Not limited to this, when a plurality of layers are not formed in the process chamber Px, one crucible and one heating source may be provided. Further, when vapor-depositing a plurality of layers, a number of crucibles, a heating source, etc., which are larger than the number of layers, may be provided.

  As shown in FIG. 2B, the process chamber Px has six vapor deposition sources such as a plurality of vapor deposition sources SCx1 to SCx6. The number of vapor deposition sources may be appropriately selected according to the layer structure and material to be formed. Alternatively, it can be used as a preliminary vapor deposition source. Each evaporation source is provided with evaporation source shutters SSx1 to SSx6.

  In this way, preparation of the process chamber is completed by stabilizing at a desired vapor deposition rate in a desired vapor deposition source, and a substrate (hereinafter referred to as “wafer W”) can be carried into the process chamber.

(Wafer film formation)
After the preparation of the process chamber described above is completed, the wafer W is loaded into the loading chamber LD and loaded into the process chamber P1 via the transport chamber T1. It should be noted that a plurality of process chambers may be arranged between the wafer loading chamber LD and the transfer chamber T1 for performing a wafer pretreatment process known in the art, such as heating the wafer W, plasma ashing process, and ultraviolet irradiation process. .. In the manufacturing apparatus, the wafer W is carried in, for example, gripped by an arm.

  When the wafer W is loaded into the process chamber P1, the wafer W is set on the wafer tray WT. A mask tray MT on which a metal mask MM is set is arranged between the wafer W and the vapor deposition source. The metal mask MM is provided with an opening for forming a desired layer at a predetermined position on the wafer W. Each process chamber Px is provided with an alignment device (not shown) for aligning the wafer W and the metal mask MM. The wafer tray WT and the mask tray MT are provided with a rotation mechanism, and the wafer W and the metal mask MM simultaneously rotate at a predetermined rotation speed during film formation (not shown). At this point, since the shutter MS arranged between the metal mask MM and the vapor deposition source is closed, no film is formed on the wafer.

  After the wafer W is loaded into the process chamber Px and the wafer W and the metal mask MM are aligned with each other, the wafer W and the metal mask MM simultaneously rotate at a desired rotation speed.

  As described above, the vapor deposition source shutter SS11 is opened before the wafer W is loaded into the process chamber Px, and the vapor deposition rate is controlled to a desired rate.

  After the wafer W is loaded into the process chamber Px and the wafer W is rotated to prepare for film formation, the shutter MS is opened to start film formation.

  First, the hole transport layer 15a is deposited in the process chamber P1. In the present embodiment, the hole transport layer 15a becomes the first layer. As the material O11, for example, a tertiary amine derivative or a carbazole derivative, which is a material of the hole transport layer 15a, is arranged in the crucible CR11. Then, in the process chamber P1, the hole transport layer 15a having a film thickness of 50 nm is formed at the vapor deposition rate (0.1 nm / sec). After the hole transport layer 15a is formed, the shutter MS is closed and the film formation of the hole transport layer 15a is completed. At this time, the vapor deposition source shutter SS11 does not have to be closed, but may be closed.

  Next, the wafer W on which the hole transport layer 15a is formed is transferred from the process chamber P1 to the process chamber P2 via the transfer chamber T1. At this time, the film formation interface of the hole transport layer 15a is exposed to the environment of the transfer chamber T1.

  Subsequently, in the process chamber P2, a light emitting layer 15b containing a light emitting material and an electron transport layer 15c are deposited. In the present embodiment, the light emitting layer 15b is the second layer and the electron transport layer 15c is the third layer.

  The light emitting layer 15b may include a host material and a light emitting dopant material (guest material). The host material is a compound having the largest weight ratio among the compounds constituting the light emitting layer. The guest material is a compound mainly responsible for light emission and has a smaller weight ratio than the host material.

  The light emitting layer 15b is roughly classified into an electron trap type and a hole trap type depending on the relationship between the molecular orbital energies of the host material and the guest material. The light emitting layer 15b is preferably an electron trap type light emitting layer. An electron trap type light emitting layer is a light emitting layer in which the lowest unoccupied molecular orbital (LUMO) of the guest material molecule is lower than the LUMO of the host material molecule. Further, the electron trap type light emitting layer may be configured such that the difference in LUMO between the guest material and the host material is larger than the difference in the highest occupied molecular orbital (HOMO) between the guest material and the host material. The LUMO difference between the guest material and the host material may be 0.15 eV or more.

  In this embodiment, after the light emitting layer 15b is formed in the same process chamber, another layer is formed without unloading the wafer W into the transfer chamber T1. Although the details will be described later, when the exposure time of the light emitting layer 15b is long, the life of the organic light emitting element tends to be particularly short. According to this embodiment, after the light emitting layer 15b is formed, the layer can be deposited while reducing the exposure time. Therefore, the life characteristics of the organic light emitting device can be improved.

  In the process chamber P2, the material O11 is a host material and the material O12 is an electron transport material. Further, a light emitting dopant material is arranged in a crucible (not shown). From the viewpoint of maintainability, the crucible in which the light emitting dopant material is arranged is preferably arranged in a position farther from the carry-in port of the process chamber P2 than the electron transport material described later.

  The light emitting layer 15b is, for example, a blue light emitting layer. As the host material, a material for recombining holes and electrons and having both charge transporting properties (bipolarity) is preferably used. As the host material, known host materials such as anthracene derivative, pyrene derivative and carbazole derivative can be used. The light emitting dopant material of the light emitting layer 15b is made of one kind of dopant material. A known fluorescent material or phosphorescent material can be used as the light emitting dopant material.

  For the electron transport layer 15c, a known material such as a metal complex having an electron transport property, a phenanthroline derivative, a heterocyclic derivative, or a hydrocarbon aromatic can be used.

  Similar to the process chamber P1, in the process chamber P2, the host material, the light emitting dopant material, and the electron transporting material are controlled to have desired vapor deposition rates until just before the wafer W is loaded. For example, the host material is controlled to 0.1 nm / sec, the light emitting dopant material is controlled to about 0.0001 to 0.001 nm / sec, and the light emitting dopant material is controlled to 0.1% to several% of the host material. Is set. The electron transporting material is controlled at 0.13 nm / sec.

  When the wafer W is transferred to the process chamber P2, the wafer W and the metal mask MM rotate.

  First, the light emitting layer 15b is formed. During the formation of the light emitting layer 15b, the evaporation source shutter SS11 of the host material and the evaporation source shutter of the light emitting dopant material (not shown) are opened, and the evaporation source shutter SS11 of the electron transporting material SS12 is closed. Since the host material and the light emitting dopant material have desired vapor deposition rates, the shutter MS can be opened to form the light emitting layer 15b. After the light emitting layer 15b reaches the desired film thickness, the shutter MS is closed to complete the formation of the light emitting layer 15b. The desired film thickness of the light emitting layer 15b is, for example, 30 nm.

  Then, the evaporation source shutter SS11 for the host material and the evaporation source shutter for the light emitting dopant material are closed, and the evaporation source shutter SS12 is opened. After confirming the vapor deposition rate of the electron transporting material, the shutter MS is opened, and a film is formed to a desired film thickness to deposit the electron transporting layer 15c. The desired film thickness of the electron transport layer 15c is, for example, 130 nm.

  The plurality of layers formed in the process chamber P2 are formed using the same mask. Therefore, as shown in FIG. 4, in plan view, the outer edges of the plurality of layers formed in the process chamber P2 coincide with each other. On the other hand, in plan view, the outer edge of the layer formed in the process chamber P1 and the outer edge of the layer formed in the process chamber P2 are deviated from each other. This is because the alignment accuracy of the metal mask MM is different in each process chamber. Specifically, the end portion of, for example, a rectangular organic film formed by the opening of the metal mask MM is formed with a deviation due to the alignment mechanism. Therefore, it is possible to read the alignment accuracy of the film forming process in each chamber from the end of the organic film of the organic light emitting element after the film formation. For example, when there is a portion with a large misalignment, it is possible to determine which process chamber the material is from by performing fluorescence characteristics by ultraviolet irradiation or film thickness measurement by optical reflectance measurement at that portion. Then, based on this determination result, it is also possible to correct the alignment of the metal mask MM of the corresponding process chamber.

  As described above, during the period from the formation of the light emitting layer 15b (second layer) to the formation of the electron transport layer 15c (third layer), the formed layer is not exposed to the environment of the transfer chamber T1. The layers are continuously formed in the process chamber P2. Further, as described above, the host material used for the light emitting layer 15b is a bipolar material. Therefore, even if the electron-transporting material is mixed, charge separation in the excited state does not occur, so that no exciplex is formed. Therefore, even if contamination occurs in the process chamber P2, its influence can be ignored. In addition, since the hole transport layer is formed in a different process chamber, the hole transport material is not mixed with the electron transport material, and the characteristics of the organic light emitting device can be prevented from being deteriorated.

  Next, the wafer W on which the light emitting layer 15b and the electron transport layer 15c are formed is transferred from the process chamber P2 to the process chamber P3 via the transfer chamber T1.

  Then, the electrode layer 16 is formed in the process chamber P3.

  The electrode layer 16 is a layer formed by performing co-evaporation of magnesium and silver using, for example, magnesium (Mg) and silver (Ag) as materials for the vapor deposition source. If necessary, lithium fluoride may be provided between the electron transport layer 15c and the electrode layer 16. For example, in the process chamber P3, three heating sources and three crucibles are prepared, and Mg, Ag, and LiF are set in each crucible. Then, for example, the deposition rate of LiF is 0.025 nm / sec, the deposition rates of Mg and Ag are 0.1 nm / sec, respectively, and LiF is 0.5 nm and Mg: Ag is 10 nm.

  Next, the wafer W on which the electrode layer 16 is formed is transferred from the process chamber P3 to the relay chamber RL. Then, the wafer W on which the electrode layer 16 is formed is transferred from the relay chamber RL to the process chamber P4 via the transfer chamber T2.

  Subsequently, the protective layer 17 is formed in the process chamber P4. The protective layer 17 includes, for example, at least one of silicon nitride and aluminum oxide. The protective layer 17 seals the layers formed in the process chamber P1 to the process chamber P3, so that adhesion of moisture or foreign matter can be prevented. The protective layer 17 may be composed of a multilayer film. As the multilayer film, a film in which aluminum oxide and silicon nitride are stacked, a film in which layers of the same material having different densities are stacked, or the like is used. The protective layer 17 only needs to have a film thickness capable of ensuring the sealing function, and preferably has a thickness within the range of 0.1 μm to 5 μm.

  Then, the wafer W on which the protective layer 17 is formed is transferred from the process chamber P4 to the wafer unloading chamber UD, and the wafer W is taken out.

  Then, the wafer W is diced to obtain a plurality of organic light emitting devices.

  As a reference diagram for explaining the effect of the present invention, FIG. 5 (A) shows the correlation between the residence time and the lifetime after each layer formation, and FIG. 5 (B) shows the correlation between the number of exposed interfaces and the lifetime of each layer. Indicates. As shown in FIG. 5A, the longer the residence time after forming each layer, the worse the life characteristics of the organic light emitting device. In particular, when the residence time after forming the light emitting layer is long, the life characteristics are likely to deteriorate. It is considered that this is because the light emitting layer is often formed of a small amount of the light emitting dopant, and even a small amount of impurities affects the energy transfer to the light emitting molecules and the carrier trapping property. Further, as shown in FIG. 5B, the life characteristics of the organic light emitting device deteriorate as the number of exposed interfaces increases.

  In the case of depositing one layer in one process chamber as described in Patent Document 1, for forming the hole transport layer 15a, the light emitting layer 15b, the electron transport layer 15c, the electrode layer 16, and the protective layer 17. In addition, 5 process chambers are required. Further, the number of interfaces exposed to the transport chamber T1 after the film formation is as follows: the interface after forming the hole transport layer 15a, the interface after forming the light emitting layer 15b, the interface after forming the electron transport layer 15c, and the electrode layer 16. There are four interfaces after the formation.

  On the other hand, according to the present embodiment, the organic light emitting device including the hole transport layer 15a, the light emitting layer 15b, the electron transport layer 15c, the electrode layer 16, and the protective layer 17 is formed in four process chambers. There is. That is, the number of process chambers can be reduced as compared with the conventional example. In addition, the number of interfaces exposed to the transport chamber T1 is three, that is, the interface after the hole transport layer 15a is formed, the interface after the electron transport layer 15c is formed, and the interface after the electrode layer 16 is formed. Can reduce the number of exposed interfaces. Therefore, the characteristics of the organic light emitting device can be improved as compared with the conventional example. In particular, as shown in FIG. 5A, when the residence time of the light emitting layer is long, the life of the organic light emitting element is significantly deteriorated. According to this embodiment, since the residence time can be shortened, the effect of improving the characteristics of the organic light emitting device becomes remarkable.

  In this embodiment, a plurality of layers are formed in the process chamber P2 after forming one layer in the process chamber P1. Not limited to this, one layer may be formed in the process chamber P1 after forming a plurality of layers in the process chamber P2.

<Second embodiment>
FIG. 6 shows a cross-sectional view of the organic light emitting device 110 according to this embodiment. This embodiment is different from the first embodiment in that a plurality of layers are formed also in the process chamber P1 and three layers are formed in the process chamber P2. The same components as those of the organic light emitting device 100 are designated by the same reference numerals, and the description thereof will be omitted.

  In this embodiment, the hole transport layer 15a, the electron blocking layer 15d, and the second light emitting layer 15e containing a light emitting material are formed in the process chamber P1. Then, in the process chamber P2, the light emitting layer 15b, the hole blocking layer 15f, and the electron transport layer 15c are formed.

  The process chamber P1 and the process chamber P2 in this embodiment will be described.

  At least five crucibles are used in the process chamber P1. The first crucible contains a hole transport material. The second crucible contains an electron blocking material. The third crucible contains the second host material of the second light emitting layer. The fourth crucible contains the second emissive dopant of the second emissive layer. The fifth crucible contains the third emissive dopant of the second emissive layer. Each crucible is set to each heating source.

  At least four crucibles are used in the process chamber P2. The first crucible contains the host material of the first light emitting layer. The second crucible contains the first emissive dopant. A hole blocking material is contained in the third crucible. The fourth crucible contains an electron transporting material. Each crucible is set to each heating source.

  In this embodiment, the number of crucibles included in the process chamber P1 is different from the number of crucibles included in the process chamber P2. Specifically, the number of crucibles included in the process chamber P1 is larger than the number of crucibles included in the process chamber P2.

  As the electron blocking material, a material having a shallower LUMO level than the host material of the second light emitting layer and having a function of preventing electron leakage from the host material can be used. For example, as a material for the electron blocking layer, a tertiary amine derivative or a carbazole derivative can be used.

  The second light emitting layer 15e is, for example, a layer that emits red and green light. The second light emitting layer 15e is preferably an electron trap type light emitting layer. As the second host material, known host materials such as anthracene derivative, pyrene derivative and carbazole derivative can be used.

  Known fluorescent materials and phosphorescent materials can be used as the second light emitting dopant and the third light emitting dopant, respectively.

  Since the configurations of the process chamber P3 and the process chamber P4 are the same as those in the first embodiment, the description thereof will be omitted.

  Next, a method for manufacturing the organic light emitting device 110 will be described. First, preparation is performed as in the first embodiment. Specifically, in the process chambers P1, P2, and P3, film formation is started on the wafer W after the materials of the layers are adjusted to have desired vapor deposition rates. The wafer W loaded from the wafer loading chamber LD is transferred to the process chamber P1 via the transfer chamber T1. After the alignment of the transferred wafer W with the metal mask MM is adjusted, the wafer W and the metal mask MM rotate and the film formation preparation is completed.

  In the process chamber P1, in order to form the hole transport layer 15a, the vapor deposition source shutter that controls the vapor deposition source of the hole transport layer 15a is opened, and the vapor deposition source shutter that controls the vapor deposition source of the hole transport layer 15a. All except the above are closed. As a result, only the hole transporting material can be formed into a film on the wafer W. After confirming the vapor deposition rate with the crystal unit XT11, the shutter MS is opened, and the hole transport layer 15a is formed on the wafer W. In this embodiment, when the hole transport layer 15a is formed to a film thickness of 15 nm at a vapor deposition rate of 0.1 nm / sec, the shutter MS is closed to complete the formation of the hole transport layer 15a.

  Next, the evaporation source shutter that controls the evaporation source of the electron block layer 15d is opened, and all the elements except the evaporation source shutter that controls the evaporation source of the electron block layer 15d are closed. Confirm the deposition rate of the electron blocking material with the crystal unit XT12. When the vapor deposition rate is stable, the shutter MS is opened, and when the vapor deposition rate becomes 0.1 nm / sec and reaches 10 nm, the shutter MS is closed to complete the formation of the electron block layer 15d.

  Next, the second light emitting layer 15e is deposited. The vapor deposition source shutter that controls the vapor deposition source of the second light emitting layer 15e is opened, and the other vapor deposition source shutters are closed. Since the second light emitting layer 15e is formed of a plurality of materials, the vapor deposition source shutter that controls the second host material, the second light emitting dopant, and the third light emitting dopant is opened. The deposition rates of the second host material, the second light emitting dopant, and the third light emitting dopant are confirmed by the crystal oscillators XT13, XT14, and XT15. When the deposition rate is stable, the shutter MS is opened, the deposition rate of the second host material is 0.1 nm / sec, the second emission dopant is 0.002 nm / sec, and the third emission dopant is 0.0005 nm / sec. To form a film. When the total film thickness of 20 nm is formed, the shutter MS is closed and the formation of the second light emitting layer 15e is completed.

  Then, the wafer W on which the second light emitting layer is formed is transferred to the process chamber P2.

  When the wafer W is loaded into the process chamber P2, the vapor deposition source shutter that controls the vapor deposition source of the light emitting layer 15b is opened, and the other vapor deposition source shutters are closed. The deposition rates of the host material and the light emitting dopant material are confirmed by the crystal units XT21 and XT22, and the shutter MS is opened. When the deposition rate of the host material is 0.1 nm / sec and the deposition rate of the light emitting dopant material is 0.005 nm / sec and 10 nm is formed, the shutter MS is closed to complete the formation of the light emitting layer 15b.

  Next, the vapor deposition source shutter that controls the vapor deposition source of the hole blocking layer 15f is opened, and all other vapor deposition source shutters are closed. After confirming the vapor deposition rate of the hole blocking material, the shutter MS is opened to form a film at a vapor deposition rate of 0.15 nm / sec. When the thickness reaches 100 nm, the shutter MS is closed and the formation of the hole blocking layer 15f is completed.

  The hole blocking material is a material having an effect of confining holes in the host material. The hole blocking material is preferably a material having a HOMO level equal to or deeper than the host material of the light emitting layer 15b, and particularly preferably a material having an electron mobility of 10 ^ -4 cm2 / Vs or more. In this specification, the deep LUMO and HOMO indicate that LUMO and HOMO are farther from the vacuum order. As the hole blocking material, for example, polycyclic aromatic hydrocarbons such as fluorene, anthracene, pyrene, chrysene, picene, and pentacene, and heterocyclic compounds such as pyridine, pyrimidine, bipyridine, and phenanthroline can be used. ..

  Next, the vapor deposition source shutter for controlling the vapor deposition source of the electron transport layer 15c is opened, and the other vapor deposition source shutters are all closed. The deposition rate of the electron transport material is confirmed by the crystal unit XT23, and the shutter MS is opened. A film is formed at a vapor deposition rate of 0.1 nm / sec, and when the film thickness becomes 30 nm, the shutter MS is closed to complete the formation of the electron transport layer 15c.

  When depositing one layer in one process chamber as in the conventional example, a hole transport layer, an electron block layer, a second light emitting layer, a light emitting layer, a hole block layer, an electron transport layer, an electrode layer, And 8 process chambers are required for the formation of the protective layer. The number of interfaces exposed to the transfer chamber T1 after the film formation is 7 interfaces.

  On the other hand, according to the present embodiment, since eight layers are formed by four process chambers, the number of process chambers can be reduced by four. Further, the number of interfaces exposed to the transfer chamber T1 can be three interfaces, that is, the interface after the second light emitting layer 15e is formed, the interface after the electron transport layer 15c is formed, and the interface of the electrode layer 16, and the number of exposed interfaces is Can be reduced.

  It is preferable that the time (tact time) from the loading and unloading of the wafer in the process chamber P1 is the same as the tact time in the process chamber P2. Thereby, even if the film formation is performed on the wafer in each process chamber at the same time, the waiting time until the wafer is loaded into the process chamber P2 can be reduced, and thus the organic light emitting device can be efficiently manufactured.

  As described above, the light emitting layer 15b and the second light emitting layer 15e contain the dopant material. The dopant material of the light emitting layer 15b is made of one kind of dopant material, and the dopant material of the second light emitting layer 15e is made of a plurality of kinds of dopant materials. Since the concentration of the dopant material is low, the light emitting layer 15b and the second light emitting layer 15e are likely to be adversely affected by the concentration shift. Therefore, in the present embodiment, in order to prevent the deviation of the concentration of the dopant material, the film formation rate of the dopant material is stabilized before the film formation of the light emitting layer 15b and the second light emitting layer 15e. .. That is, before vapor deposition of the light emitting layers 15b and 15e, it is necessary to stabilize the film formation rate. As described above, the takt time includes the time for film formation and the time for stabilizing the film formation rate. A large number of wafers can be processed by setting the takt time in each process chamber in consideration of the time for stabilizing the film formation rate.

  Thus, when the organic light emitting device includes a plurality of light emitting layers, it is preferable that each light emitting layer be deposited by different process chambers. As a result, the takt time in one process chamber can be shortened as compared with the case where a plurality of light emitting layers are vapor-deposited in the same process chamber, and the takt time in vapor-depositing each layer can be easily aligned.

  The total time for film formation in each process chamber is, for example, 450 sec in the process chamber P1, 900 sec in the process chamber P2, and 70 sec in the process chamber P3. Here, the total time for film formation refers to the total time from the opening of the shutter MS to the closing of the shutter MS in each layer. The total time for forming a film is half the total time for forming a film in the process chamber P2. However, in the present embodiment, since the second light emitting layer 15e contains a plurality of dopant materials, it takes time to stabilize the film formation rate. Therefore, the takt time in the process chamber P1 and the takt time in the process chamber P2 can be made substantially the same.

  The takt time in the process chamber P2 may be shorter than the takt time in the process chamber P1. Thus, the wafer can be loaded into the process chamber P2 immediately after the film formation in the process chamber P1 is completed, and thus the exposure time in the core chamber can be shortened.

  The second host material of the second light emitting layer 15e and the host material of the light emitting layer 15b are preferably bipolar materials. The second host material of the second light emitting layer 15e and the host material of the light emitting layer 15b may be different or the same.

  In the process chamber P1, each layer is formed using only the hole transporting material and the bipolar material of the second light emitting layer, and in the process chamber P2, the light emitting layer (bipolar material) and the electron transporting material. I'm only using Therefore, even if contamination occurs, the excited charge transfer complex does not form, and the influence on the characteristics of the organic light emitting device can be ignored.

<Third embodiment>
FIG. 7 shows a cross-sectional view of the organic light emitting device 120 according to this embodiment. This embodiment is the same as the second embodiment except that the hole transport layer 15a, the electron blocking layer 15d, the second light emitting layer 15e, and the intermediate layer 15g are vapor-deposited in the process chamber P1. The same components as those of the organic light emitting device 110 are designated by the same reference numerals, and the description thereof will be omitted.

  The intermediate layer 15g is configured to reduce the influence of interface exposure after forming the second light emitting layer 15e. Since the intermediate layer 15g is formed, the exposure time at the interface of the second light emitting layer 15g can be shortened, and thus the reduction in the life of the organic light emitting element can be suppressed.

  The intermediate layer 15g is a layer made of a material different from that of the second light emitting layer 15e. The intermediate layer 15g may be composed of the second host material of the second light emitting layer. Alternatively, the intermediate layer 15g may be composed of a hole transporting material, an electron blocking material, a second host material, a second light emitting dopant material, and a bipolar material different from the third light emitting dopant material. Good.

  A manufacturing method when the intermediate layer 15g is made of the second host material will be described. After forming the second light emitting layer 15e, the vapor deposition source shutter of the second light emitting dopant material and the vapor deposition source shutter of the third light emitting dopant material of the second light emitting layer 15e are closed to stop the supply of the light emitting dopant material. Thereby, the intermediate layer 15g, which is a layer formed of the second host material of the second light emitting layer and containing no light emitting dopant material, can be continuously vapor-deposited after forming the second light emitting layer.

<Fourth Embodiment>
FIG. 8 shows a cross-sectional view of the organic light emitting device 130 according to this embodiment. In this embodiment, the hole transport layer 15a and the electron blocking layer 15d are formed in the process chamber P1, and the second light emitting layer 15e, the light emitting layer 15b, and the hole blocking layer 15f are formed in the process chamber P2. It differs from the second embodiment. The same components as those of the organic light emitting device 110 are designated by the same reference numerals, and the description thereof will be omitted.

  According to the present embodiment, the interface of the second light emitting layer 15e and the interface of the second light emitting layer 15b are not exposed to the transport chamber T1, so that the deterioration of the life characteristics of the organic light emitting element can be suppressed.

<Fifth Embodiment>
FIG. 9 shows a cross-sectional view of the organic light emitting device 140 according to this embodiment. In this embodiment, a part of the light emitting layer 15b and the hole blocking layer 15f are formed in the process chamber P2, and another part of the hole blocking layer 15f and the electron transport layer 15c are deposited in the process chamber P5 (not shown). This is different from the first to fourth embodiments in that The same components as those of the organic light emitting devices 100 to 140 are designated by the same reference numerals, and the description thereof will be omitted.

  The hole blocking layer 15f may be thicker than other layers. When film formation of a large number of wafers is performed in parallel, if the film thicknesses of the respective layers are significantly different from each other, the wafers after film formation may stay in the process chamber where the vapor deposition time is short. In this case, it is possible to match the film forming time in each chamber by increasing the number of process chambers.

  Specifically, in the first embodiment, the process chamber P5 is provided in the transfer chamber T1. In the process chamber P5, the hole blocking material and the electron transporting material are respectively adjusted at the vapor deposition rate of 0.2 nm / sec.

  After forming the hole transport layer 15a (15 nm) and the electron blocking layer 15d (10 nm) in the process chamber P1 at a vapor deposition rate of 0.05 nm / sec, respectively, the light emitting layer 15b and the hole blocking layer 15f are formed in the process chamber P2. Partially deposit. For example, when the hole blocking layer 15f has a thickness of 100 nm and the electron transporting layer 15c has a thickness of 30 nm, the hole blocking layer 15c is partially deposited to 30 nm in the process chamber P2. Here, the film forming process in the process chamber P2 is completed. Next, it is conveyed to the process chamber P5, and the remaining thickness (70 nm) of the hole blocking layer 15f and the electron transport layer 15c (30 nm) are deposited. At this time, the vapor deposition process time of each organic film in the process chambers P1, P2, and P5 can be adjusted to 500 sec. By doing so, the deposition time can be made the same in a manufacturing process in which a large number of wafers W are continuously formed, and thus unnecessary retention in the chamber can be suppressed. Although the number of exposed interfaces in the transport chamber T1 can be increased, the interface of the light emitting layer 15b can be protected by the electron transport layer 15c, so that the life characteristics of the organic light emitting device can be improved.

  Although the wafer W used in each of the above-described embodiments is described as having a circular shape, the shape may be rectangular. Further, the wafer W may be a glass substrate or a Si substrate, or may be one on which a drive circuit for driving the organic light emitting element is formed.

  In each of the above-described embodiments, the hole transport layer may be formed in the process chamber P1 and the electron transport layer may be formed in the process chamber P2 or P3.

1000 film forming apparatus W wafer LD wafer loading chamber GV gate valve T1 transport chamber AR1 transport arm P1 process chamber WT1 process chamber wafer tray P2 process chamber P3 process chamber RL relay chamber T2 transport chamber P4 process chamber UD wafer unloading chamber 100 organic light emitting device 10 substrate 11 electrode (anode)
16 electrodes (cathode)
17 Protective layer

Claims (22)

A method for manufacturing an organic light emitting device including a plurality of organic layers, comprising:
Depositing a first layer of the plurality of organic layers on a substrate in a first chamber;
In the second chamber, a second layer of the plurality of organic layers, and a third layer made of a material different from the second layer of the plurality of organic layers, the substrate in the second chamber And a step of vapor deposition without carrying it out from the manufacturing method.   The manufacturing method according to claim 1, wherein a step of depositing the second layer and the third layer is performed after the step of depositing the first layer.   The manufacturing method according to claim 1, wherein the second layer is a light emitting layer containing a light emitting material.   The method according to claim 3, wherein the light emitting layer is an electron trap type light emitting layer. The first layer is a hole transport layer,
The said 3rd layer is an electron carrying layer, The manufacturing method of any one of Claim 1 thru | or 4 characterized by the above-mentioned.   The method according to claim 4, wherein a hole blocking layer is deposited in the second chamber after depositing the second layer and before depositing the third layer.   7. The manufacturing method according to claim 1, wherein the second layer and the third layer are deposited using the same mask.   The manufacturing method according to claim 1, wherein a plurality of layers including the first layer are deposited in the first chamber without unloading the substrate from the first chamber. .. The plurality of organic layers include a fourth layer including a second light emitting layer containing a light emitting dopant material and a host material, and an intermediate layer containing the host material,
In the first chamber, after forming the fourth layer, the supply of the light emitting dopant material is stopped and the intermediate layer is deposited without unloading the substrate from the first chamber. 8. The manufacturing method according to 8. The third layer is part of the hole blocking layer,
The method of claim 4, wherein another part of the hole blocking layer is deposited in the third chamber.   The manufacturing method according to claim 1, wherein in the second chamber, a second light emitting layer is deposited as the second layer, a light emitting layer is deposited as the third layer, and a hole blocking layer is deposited as a fourth layer. A method of manufacturing an organic light emitting device, comprising:
Depositing a hole transport layer, an electron blocking layer, and a second light emitting layer on the substrate in the first chamber without unloading the substrate from the first chamber;
Depositing the light emitting layer, the hole blocking layer, and the electron transport layer in the second chamber without unloading the substrate from the second chamber.   The method according to claim 12, wherein the light emitting layer is an electron trap type light emitting layer.   The method according to claim 13, wherein the second light emitting layer is an electron trap type light emitting layer. The dopant material of the light emitting layer comprises one kind of dopant material,
The method according to claim 14, wherein the dopant material of the second light emitting layer comprises a plurality of kinds of dopant materials.   The total time for depositing the light emitting layer, the hole blocking layer, and the electron transporting layer in the second chamber is equal to the total time of depositing the hole transporting layer, the electron blocking layer, and the second light emitting layer in the first chamber. The manufacturing method according to claim 15, wherein the total time for depositing the layer is equal to or longer than the total time.   The manufacturing method according to claim 16, wherein the deposition rate of the second light emitting layer is adjusted after the electron blocking layer is deposited and before the second light emitting layer is deposited. The length of time from when the substrate is loaded into the first chamber to when it is unloaded;
18. The manufacturing method according to claim 17, wherein the length of time from when the substrate is loaded into the second chamber to when it is unloaded is the same. A manufacturing apparatus of an organic light emitting device,
A manufacturing apparatus characterized in that the number of crucibles in the first chamber and the number of crucibles in the second chamber are different. An organic light emitting device in which a plurality of organic layers are laminated,
In a plan view, the outer edge of the first layer of the plurality of organic layers and the outer edge of the second layer made of a material different from the first layer of the plurality of organic layers are displaced from each other, and An organic light emitting device, wherein an outer edge of a layer and an outer edge of a third layer made of a material different from that of the second layer of the plurality of organic layers coincide with each other.   The organic light emitting device of claim 20, wherein the second layer is an electron trap type light emitting layer. The first layer is a hole transport layer,
22. The organic light emitting device according to claim 21, wherein the third layer is an electron transport layer.

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