JP2012060174A - Display apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display apparatus including red organic light-emitting devices capable of being formed by a simplified process with the thermal transfer method.SOLUTION: A display apparatus comprises: a red organic light-emitting element having, on a substrate, a first electrode, a red organic layer including a mixed layer containing a red light-emitting material, green light-emitting material, and at least one of a positive hole transporting material, an electron transporting material, and a positive/negative charge transporting material; and a second electrode in the order given; and a green organic light-emitting element having, on the substrate, the first electrode, a green organic layer including a green monochrome layer containing a green light-emitting material, and at least one of a positive hole transporting material, an electron transporting material, and a positive/negative transporting material, and the second electrode in the order given. The green light-emitting material included in the green monochrome layer and the green light-emitting material included in the mixed layer are the same.

Description

  The present invention relates to a red organic light-emitting element and a display device formed by a thermal transfer method, a donor substrate and a transfer method used for manufacturing the display device, a display device manufacturing method, and a display device manufacturing system.

  As one method for manufacturing an organic light-emitting element, a pattern manufacturing method using thermal transfer is disclosed (for example, see Patent Document 1 and Patent Document 2). In the conventional thermal transfer method, in order to form organic light emitting elements of three colors of red, green, and blue, generally three times of transfer are required as with the number of emitted colors. The same applies to the case where a common layer is employed as a part of the organic layer (see, for example, Patent Document 3).

JP 9-167684 A JP 2002-216957 A JP 2005-235742 A

  However, the transfer method requires a number of complicated processes such as alignment, separation, and laser irradiation of the donor substrate and the substrate to be transferred, leading to complicated and expensive equipment, and shortening the tact time. It was. Further, since a donor substrate for each color is required, there is a problem that the running cost is high.

  The present invention has been made in view of such a problem, and an object thereof is to provide a red organic light-emitting element that can be formed by a simple process using a thermal transfer method, a display device including the red organic light-emitting element, and a donor used in the manufacture thereof. It is an object to provide a substrate, a transfer method, a display device manufacturing method, and a display device manufacturing system.

  The red organic light-emitting device according to the present invention includes, on a substrate, a first electrode, a red organic layer having a mixed layer containing a red light-emitting material and a green light-emitting material, and a second electrode in order.

  A display device according to the present invention includes the red organic light-emitting element according to the present invention.

  In the red organic light-emitting device according to the present invention or the display device according to the present invention, the red organic layer has a mixed layer containing a red light-emitting material and a green light-emitting material, so that energy transfer occurs in red having a low energy level. , Red emission becomes dominant.

  In the first donor substrate according to the present invention, a transfer layer is selectively formed on a part of the front surface side of the substrate, and the transfer layer is transferred to another substrate by irradiating radiation from the back surface side of the substrate. As seen from the surface side of the substrate, a reflective layer is provided in a transfer layer formation scheduled region, and an absorption layer is provided in a region other than the transfer layer formation planned region.

  A first transfer method according to the present invention is a method in which a transfer layer is transferred from a donor substrate having a transfer layer selectively formed on a part of the substrate to another substrate, and the donor substrate is viewed from the surface side of the substrate. A step of forming a transfer layer on the entire surface side of the substrate using a reflection layer provided in a region where the transfer layer is to be formed and an absorption layer provided in a region other than the region where the transfer layer is to be formed; A step of selectively removing the transfer layer in the region where the absorption layer is formed as seen from the surface side of the substrate by irradiating radiation from the surface side of the substrate, and a substrate in which the donor substrate and another substrate are arranged to face each other And transferring the transfer layer on the reflective layer to another substrate by irradiating radiation from the back side of the substrate.

  The first transfer method according to the present invention uses the first donor substrate of the present invention, and after the transfer layer is formed on the entire surface side of the substrate, radiation is irradiated from the surface side of the substrate. As a result, the transfer layer in the region where the absorption layer is formed as viewed from the surface side of the substrate is selectively removed, and the transfer layer remains only on the reflective layer. After that, the donor substrate and the other substrate are arranged to face each other, and the transfer layer on the reflective layer is transferred by irradiating radiation from the back side of the substrate.

  The second donor substrate according to the present invention is for forming a transfer layer on the surface side of the base and selectively transferring a part of the transfer layer to another substrate by irradiating radiation from the back side of the base. As viewed from the back side of the substrate, a reflection layer is provided in a non-transfer area where the transfer layer is not transferred to another substrate, and an absorption layer is provided in an area other than the non-transfer area. .

  In the second transfer method according to the present invention, a part of the transfer layer is selectively transferred from the donor substrate having the transfer layer formed on the substrate to another substrate, and the donor substrate is viewed from the back side of the substrate. The transfer layer is formed on the entire surface side of the substrate using a reflection layer provided in a non-transfer area where the transfer layer is not transferred to another substrate and an absorption layer provided in an area other than the non-transfer area. And a step of selectively transferring a portion of the transfer layer other than the non-transfer region to the other substrate by arranging the donor substrate and the other substrate facing each other and irradiating radiation from the back side of the substrate. It is a waste.

  The second transfer method according to the present invention uses the second donor substrate of the present invention, and after the transfer layer is formed on the entire surface side of the substrate, the donor substrate and another substrate are arranged to face each other. By irradiating with radiation from the back surface side, a portion of the transfer layer other than the non-transfer region is selectively transferred to another substrate, and the portion of the non-transfer region remains on the substrate without being transferred.

  A manufacturing method of a display device according to the present invention is a method for manufacturing a display device having a red organic light emitting element, a green organic light emitting element, and a blue organic light emitting element on a substrate. The red transfer layer formation planned region corresponding to the light emitting element formation planned region has a reflective layer, and the region other than the red transfer layer formation planned region has an absorption layer, while the green transfer layer non-transfer region is viewed from the back side of the substrate. In this case, a donor substrate having an absorbing layer is used for the region other than the reflective layer and the green transfer layer non-transfer region, a red transfer layer containing a red light emitting material is formed on the entire surface side of the substrate, and radiation is emitted from the surface side of the substrate. Is used to selectively remove the red transfer layer in the region where the absorption layer is formed when viewed from the surface side of the substrate, and then form a green transfer layer containing a green light emitting material on the entire surface side of the substrate. Layered By transferring the process and the donor substrate and the substrate facing each other and irradiating radiation from the back side of the substrate, the red transfer layer and the green transfer layer other than the green transfer layer non-transfer region are collectively transferred to the substrate. And a batch transfer process.

  A display device manufacturing system according to the present invention manufactures a display device having a red organic light-emitting element, a green organic light-emitting element, and a blue organic light-emitting element on a substrate. The red transfer layer formation planned region corresponding to the light emitting element formation planned region has a reflective layer, and the region other than the red transfer layer formation planned region has an absorption layer, while the green transfer layer non-transfer region is viewed from the back side of the substrate. A donor layer having an absorbing layer in a region other than the reflective layer and the green transfer layer non-transfer region, a red transfer layer forming portion for forming a red transfer layer containing a red light emitting material on the entire surface side of the substrate, A transfer layer selective removal portion that selectively removes the red transfer layer in the region where the absorption layer is formed as viewed from the surface side of the substrate by irradiating radiation from the surface side, and the entire surface side of the substrate Green A red transfer layer and a green color are formed by irradiating radiation from the back side of the substrate by arranging a transfer layer forming unit including a green transfer layer forming unit that forms a green transfer layer containing a luminescent material, and a donor substrate and a substrate facing each other. The transfer layer includes a batch transfer portion that batch-transfers a portion other than the green transfer layer non-transfer region to the substrate.

  According to the red organic light-emitting element of the present invention or the display device of the present invention, the red organic layer has a mixed layer containing a red light-emitting material and a green light-emitting material. The mixed layer can be formed by a simple process of batch transferring the red transfer layer containing the material and the green transfer layer containing the green light emitting material.

  According to the first transfer method of the present invention, since the first donor substrate of the present invention is used, the transfer layer is formed on the entire surface side of the substrate, and then transferred by irradiation with radiation from the surface side of the substrate. The layer can be selectively removed, leaving the transfer layer only on the reflective layer.

  According to the second transfer method of the present invention, since the second donor substrate of the present invention is used, after forming the transfer layer on the entire surface side of the substrate, the donor substrate and the substrate are arranged to face each other and the back surface side of the substrate. The portion of the transfer layer other than the non-transfer region can be selectively transferred to the substrate by irradiating with radiation from the substrate, and the portion of the non-transfer region can be left on the substrate without being transferred.

  According to the display device manufacturing method of the present invention or the display device manufacturing system of the present invention, the donor substrate of the present invention is used, and a red transfer layer and a green transfer layer are formed on the donor substrate and collectively transferred to the substrate. Since it did in this way, the transfer for forming a red organic light emitting element and a green organic light emitting element can be performed at once, and it can manufacture by a simple process.

It is sectional drawing showing the structure of the display apparatus which concerns on one embodiment of this invention. It is a flowchart showing the flow of the manufacturing method of the display apparatus shown in FIG. It is sectional drawing showing the manufacturing method shown in FIG. 2 in order of a process. It is sectional drawing showing the structure of the donor substrate used in the manufacturing method shown in FIG. FIG. 5 is a cross-sectional view illustrating a modified example of the donor substrate illustrated in FIG. 4. FIG. 4 is a cross-sectional view illustrating a process following FIG. 3. FIG. 7 is a cross-sectional view illustrating a process following FIG. 6. FIG. 8 is a cross-sectional diagram illustrating a process following the process in FIG. 7. FIG. 9 is a cross-sectional diagram illustrating a process following the process in FIG. 8. It is sectional drawing showing the process of preparation and reproduction | regeneration of a donor substrate in order of a process. FIG. 10 is a cross-sectional diagram illustrating a process following the process in FIG. 9. It is a figure which represents roughly an example of the manufacturing system of the display apparatus by the manufacturing method of the display apparatus shown in FIG. It is sectional drawing showing the structure of the donor substrate which concerns on the modification of this invention. FIG. 14 is a cross-sectional view illustrating a modified example of the donor substrate illustrated in FIG. 13. FIG. 14 is a cross-sectional view illustrating another modification of the donor substrate illustrated in FIG. 13.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a cross-sectional structure of a display device using a red organic light emitting element according to an embodiment of the present invention. This display device is used as an ultra-thin organic light emitting color display device. For example, on a substrate 11 made of glass or the like, a red organic light emitting element 10R that generates red light and green light are emitted. The generated green organic light emitting element 10G and the blue organic light emitting element 10B generating blue light are sequentially formed in a matrix as a whole. The red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B have a rectangular planar shape, and are a combination of the adjacent red organic light emitting element 10R, green organic light emitting element 10G, and blue organic light emitting element 10B. Constitutes one pixel. The pixel pitch is, for example, 300 μm.

  In the red organic light emitting element 10R, a first electrode 12 as an anode, an insulating film 13, a red organic layer 14R including a mixed layer 14RC described later, and a second electrode 15 as a cathode are stacked in this order from the substrate 11 side. It has a configuration. The green organic light emitting element 10G has a configuration in which a first electrode 12, an insulating film 13, a green organic layer 14G including a green monochrome layer 14GC described later, and a second electrode 15 are stacked in this order from the substrate 11 side. ing. The blue organic light emitting element 10B has a configuration in which a first electrode 12, an insulating film 13, a blue organic layer 14B including a blue monochrome layer 14D described later, and a second electrode 15 are stacked in this order from the substrate 11 side. ing.

  The red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B are covered with a protective film 16, and are further sealed with an adhesive layer 20 on the protective film 16 and made of glass or the like. The substrate 30 is sealed by being bonded over the entire surface.

  The first electrode 12 is made of, for example, ITO (indium / tin composite oxide). The first electrode 12 is provided on a TFT (thin film transistor) formed on the substrate 11 and a planarization insulating film (none of which is shown) covering the TFT 11 to enable active matrix driving. Also good. In that case, the first electrode 12 is electrically connected to the TFT through a contact hole provided in the planarization insulating film.

  The insulating film 13 is used to ensure insulation between the first electrode 12 and the second electrode 15 and to accurately form the light emitting region in a desired shape. For example, the insulating film 13 is made of a photosensitive resin such as polyimide. . The insulating film 13 has an opening corresponding to the light emitting region.

  The red organic layer 14R has, for example, a configuration in which a hole injection layer 14A1, a hole transport layer 14A2, a mixed layer 14RC, a blue monochromatic layer 14D, and an electron transport layer 14E are stacked in this order from the first electrode 12 side. For example, the green organic layer 14G has a configuration in which a hole injection layer 14A1, a hole transport layer 14A2, a green monochrome layer 14GC, a blue monochrome layer 14D, and an electron transport layer 14E are stacked in this order from the first electrode 12 side. For example, the blue organic layer 14B has a configuration in which a hole injection layer 14A1, a hole transport layer 14A2, a blue monochromatic layer 14D, and an electron transport layer 14E are stacked in this order from the first electrode 12 side. Among these, the hole injection layer 14A1, the hole transport layer 14A2, the blue monochromatic layer 14D, and the electron transport layer 14E are common layers of the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B. The hole injection layer 14A1 is a buffer layer for improving hole injection efficiency and preventing leakage. The hole transport layer 14A2 is for increasing the hole transport efficiency to the mixed layer 14RC, the green monochromatic layer 14GC, and the blue monochromatic layer 14D, which are light emitting layers. The mixed layer 14RC, the green monochromatic layer 14GC, and the blue monochromatic layer 14D generate light by recombination of electrons and holes when an electric field is applied. The electron transport layer 14E is for increasing the efficiency of electron transport to the mixed layer 14RC, the green monochrome layer 14GC, and the blue monochrome layer 14D. Note that the hole injection layer 14A1, the hole transport layer 14A2, and the electron transport layer 14E may be provided as necessary, and may have different configurations depending on the emission color. An electron injection layer (not shown) made of LiF, Li2O, or the like may be provided between the electron transport layer 14D and the second electrode 15.

  The hole injection layer 14A1 has, for example, a thickness of 5 nm to 300 nm, for example 25 nm, and 4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine (m-MTDATA) or 4,4 It is composed of ', 4 "-tris (2-naphthylphenylamino) triphenylamine (2-TNATA). The hole transport layer 14A2 has, for example, a thickness of 5 nm to 300 nm, for example, 30 nm, and is composed of 4,4′-bis (N-1-naphthyl-N-phenylamino) biphenyl (α-NPD). .

  The mixed layer 14RC includes a red light emitting material and at least one of a hole transporting material, an electron transporting material, and both charge transporting materials. The red light emitting material may be fluorescent or phosphorescent. The mixed layer 14RC has, for example, a thickness of 10 nm to 100 nm, for example, 15 nm, and 2,6-bis [(4′-methoxydiphenylamino) styryl] as a red light emitting material in ADN (di (2-naphthyl) anthracene). It is composed of 30% by weight of -1,5-dicyanonaphthalene (BSN).

  The green monochromatic layer 14GC includes a green light emitting material and at least one of a hole transporting material, an electron transporting material, and a charge transporting material. The green light emitting material may be fluorescent or phosphorescent. The green monochromatic layer 14GC has, for example, a thickness of 10 nm to 100 nm, for example, 15 nm, and is composed of ADN mixed with 5 wt% of coumarin 6 as a green light emitting material.

  The blue monochromatic layer 14D includes a blue light emitting material and at least one of a hole transporting material, an electron transporting material, and a charge transporting material. The blue light emitting material may be fluorescent or phosphorescent. The blue monochromatic layer 14D has, for example, a thickness of 10 nm to 100 nm, for example, 15 nm, and 4,4′-bis [2- {4- (N, N-diphenylamino) phenyl} vinyl] as a blue light emitting material for ADN. It is composed of a mixture of 2.5% by weight of biphenyl (DPAVBi).

  The electron transport layer 14E has, for example, a thickness of 5 nm to 300 nm, for example, 20 nm, and is made of 8-hydroxyquinoline aluminum (Alq3).

  The second electrode 15 is composed of a transparent electrode or a semi-transmissive electrode, and light generated in the mixed layer 14RC, the green monochrome layer 14GC, and the blue monochrome layer 14C is extracted from the second electrode 15 side. . For example, the second electrode 15 has a thickness of 5 nm or more and 50 nm or less, and is made of a simple substance or an alloy of a metal element such as aluminum (Al), magnesium (Mg), calcium (Ca), or sodium (Na). Among these, an alloy of magnesium and silver (MgAg alloy) is preferable.

  The protective film 16 is for preventing moisture and the like from entering the red organic layer 14R, the green organic layer 14G, and the blue organic layer 14B. It has a thickness. Further, the protective film 16 is made of a material having high transmittance with respect to light generated in the mixed layer 14RC, the green monochrome layer 14GC, and the blue monochrome layer 14C, and having a transmittance of 80% or more, for example. Such a protective film 16 has, for example, a thickness of about 2 μm to 3 μm and is made of an inorganic amorphous insulating material. Specifically, amorphous silicon (α-Si), amorphous silicon carbide (α-SiC), amorphous silicon nitride (α-Si1-xNx), and amorphous carbon (α-C) are preferable. Since these inorganic amorphous insulating materials do not constitute grains, the water permeability is low and a good protective film 16 is obtained. Further, the protective film 16 may be made of a transparent conductive material such as ITO.

  The adhesive layer 20 is made of, for example, a thermosetting resin or an ultraviolet curable resin.

  The sealing substrate 30 is located on the second electrode 15 side of the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B, and together with the adhesive layer 20, the red organic light emitting element 10R and the green organic light emitting element. The element 10G and the blue organic light emitting element 10B are sealed. Further, the sealing substrate 30 takes out the light generated in the mixed layer 14RC, the green monochromatic layer 14GC, and the blue monochromatic layer 14C from the second electrode 15 side. Therefore, the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic It is made of a material such as glass that is transparent to the light generated by the light emitting element 10B.

  This display device can be manufactured, for example, as follows.

  FIG. 2 is a flowchart showing the flow of the manufacturing method of the display device, and FIGS. 3 to 11 show the manufacturing method shown in FIG. 2 in the order of steps.

  First, as shown in FIG. 3A, the first electrode 12 made of the above-described material is formed on the substrate 11 made of the above-described material by, for example, sputtering, and is formed into a predetermined shape by, for example, dry etching. Molding is performed (step S101). Note that an alignment mark used for alignment with the donor substrate in a batch transfer process described later is formed at a predetermined position of the substrate 11.

  Next, similarly as shown in FIG. 3A, a photosensitive resin is applied over the entire surface of the substrate 11, formed by, for example, photolithography, an opening is provided in a portion corresponding to the first electrode 12, and firing is performed. Then, the insulating film 13 is formed (step S102).

  Subsequently, as shown in FIG. 3B, the hole injection layer 14A1 and the hole transport layer 14A2 made of the above-described thickness and material are sequentially formed by, eg, vapor deposition (step S103).

  After that, the mixed layer 14RC is formed on the formation region 10R1 of the red organic light emitting element 10R on the hole transport layer 14A2 by a thermal transfer method using a donor substrate, and the formation region 10G1 of the green organic light emitting element 10G is formed. The green monochrome layer 14GC is formed on the substrate. This step includes a transfer layer forming step and a batch transfer step.

(Configuration of donor substrate)
FIG. 4 shows the configuration of the donor substrate used in this step in an unused state where no transfer layer is formed. The donor substrate 100 has a reflective layer 120 and an absorption layer 130 on the surface side of the base 110, that is, on the side facing the substrate 11. The base 110 is made of a material that can be aligned with the substrate 11 and has high transparency to the laser light, for example, a resin such as glass or acrylic. The reflective layer 120 is made of a metal material having a high reflectance such as silver (Ag) or an alloy containing silver (Ag). In addition, as long as it is limited to the long wavelength region, the constituent material of the reflective layer 120 may be gold (Au), copper (Cu), or an alloy containing these. The absorption layer 130 is made of a metal material having a high absorption rate such as chromium (Cr), molybdenum (Mo), titanium (Ti), or an alloy containing these. The absorption layer 130 may be made of carbon (C) or a black pigment.

  The donor substrate 100 includes a reflective layer 120 in the red transfer layer formation scheduled region 100R1 corresponding to the planned formation region of the red organic light emitting element 10R on the substrate 11 and an absorption layer in the other regions when viewed from the surface side of the substrate 110. 130. Thereby, in this donor substrate 100, the red transfer layer can be selectively formed only on the reflective layer 120.

  In addition, the donor substrate 100 has a green transfer layer non-transfer region (hereinafter simply referred to as “non-transfer region”) 100NP as viewed from the back side of the base 110, and a reflective layer 120 in the other regions, and an absorption layer 130 in other regions. Have. Thereby, in this donor substrate 100, the green transfer layer in the non-transfer region 100NP can be left on the substrate 110 without being transferred to the substrate 11. The non-transfer area 100NP corresponds to the formation planned area 10B1 of the blue organic light emitting element 10B on the substrate 11.

  In the red transfer layer formation planned region 100R1, an absorption layer 130 and a reflection layer 120 are formed in this order from the base 110 side. Thus, by providing the absorption layer 130 between the reflective layer 120 and the base 110, the red transfer layer can be transferred to the substrate 11 by irradiating the laser beam from the back side of the base 110.

  Note that the laminated structure of the reflective layer 120 and the absorbing layer 130 on the substrate 110 is not limited to the one shown in FIG. 4 as long as the above-described conditions are satisfied, and may be another laminated structure. For example, FIG. 4 shows a configuration in which the absorption layer 130 and the reflective layer 120 are partially provided on the entire surface side of the base 110, but as shown in FIG. The reflective layer 130 and the absorbing layer 130 may be partially provided.

(Transfer layer formation process)
For this donor substrate 100, first, as shown in FIG. 6A, a red transfer layer 200R containing the above-described red light emitting material is formed on the entire surface of the base 110 by, for example, vacuum deposition (step). S201).

Next, as shown in FIG. 6B, in a vacuum, the transparent substrate 300 for collecting the removed substance is brought close to or in close contact with the donor substrate 100, and the laser is emitted from the surface side of the base 110 through the transparent substrate 300. Irradiate light LB1. Since the laser beam LB1 is photothermally converted by the absorption layer 130, the red transfer layer 200R in the region where the absorption layer 130 is formed as viewed from the surface side of the substrate 110 is selectively removed (step S202). As a result, the red transfer layer 200R is formed only in the red transfer layer formation planned region 100R1. At this time, since the reflective layer 120 is provided in the red transfer layer forming region 100R1, a complicated process of shaping the spot shape of the laser beam and selectively irradiating only the predetermined region as in the prior art becomes unnecessary, and the laser beam LB1. Can be left without removing only the red transfer layer 200R on the reflective layer 120. The use of a semiconductor laser beam having a wavelength of 800nm, for example, as a laser beam LB1, as the irradiation conditions for example 0.3mW / μm ^2, it is possible to scan speed 50 mm / s.

  Subsequently, as shown in FIG. 7, the green transfer layer 200G containing the above-described green light emitting material is formed on the entire surface of the base 110 by, for example, vacuum deposition (step S203). As described above, the donor substrate 100 in which the red transfer layer 200R is formed on a part of the surface side of the substrate 110 and the green transfer layer 200G is formed on the entire surface side is formed.

(Batch transfer process)
After that, as shown in FIG. 8, the donor substrate 100 and the substrate 11 are arranged to face each other, and the laser beam LB2 is irradiated from the back surface side of the base 110, whereby the red transfer layer 200R and the green transfer layer 200G. A portion other than the non-transfer area 100NP is collectively transferred to the substrate 11 (step S300). As a result, as shown in FIG. 9, the mixed layer 14RC is formed in the planned formation region 10R1 of the red organic light emitting element 10R, and at the same time, the green monochromatic layer 14GC is formed in the planned formation region 10G1 of the green organic light emitting element 10G. It is formed. At this time, since the reflection layer 120 is provided in the non-transfer area 100NP, the complicated process of forming the spot shape of the laser light and selectively irradiating the predetermined area as in the prior art becomes unnecessary, and the laser light LB2 is formed. Without being transferred, only the green transfer layer 200G in the non-transfer area 100NP can be left without being transferred. The use of a semiconductor laser beam having a wavelength of 800nm, for example, as a laser light LB2, as the irradiation conditions for example 0.3mW / μm ^2, it is possible to scan speed 50 mm / s.

  After performing the batch transfer process, the donor substrate 100 is subjected to the transfer layer forming process (steps S201, S202, S203) described above again in order to re-form the red transfer layer 200R and the green transfer layer 200G. A batch transfer process is performed on the substrate 11. FIG. 10 shows a process of producing and regenerating such a donor substrate 100. On the unused donor substrate 100 shown in FIG. 10A, a red transfer layer 200R is formed on the entire surface side of the substrate 110 as shown in FIG. 10B (step S201). After selectively removing the red transfer layer 200R by irradiation with the laser beam LB1 as shown in FIG. 10C (step S202), the green transfer is performed on the entire surface side of the substrate 110 as shown in FIG. The layer 200G is formed (step S203). Next, a batch transfer process is performed as shown in FIG. 10E (step S300). At this time, the green transfer layer 200G remains in the non-transfer region 100NP of the donor substrate 100. Subsequently, as shown in FIG. 10F, a red transfer layer 200R is formed on the surface side of the substrate 110 while the green transfer layer 200G remains in the non-transfer region 100NP (step S201), and FIG. When the laser beam LB1 is irradiated as shown in C), the red transfer layer 200R can be selectively removed, and at the same time, the green transfer layer 200G remaining in the non-transfer region 100NP can be removed (step S202). After that, as shown in FIG. 10D, a green transfer layer 200G is formed on the entire surface side of the substrate 110 (step S203). In this manner, a closed loop of the steps shown in FIGS. 10C to 10F can be configured, and a process or apparatus for cleaning and reusing the donor substrate 100 after batch transfer is unnecessary. In addition, the donor substrate can be used repeatedly without being discarded after being used once.

(Blue monochromatic layer formation process)
On the other hand, as shown in FIG. 11, the blue monochromatic layer 14D containing the above-described blue light-emitting material is formed on the entire surface of the substrate 11 after the batch transfer process as shown in FIG. 11 (step S401). As a result, it is not necessary to perform the transfer three times as in the conventional case, and the number of transfers can be reduced to one.

  Further, following the blue monochrome layer 14D, the electron transport layer 14E and the second electrode 15 are also formed on the entire surface by, for example, vapor deposition (step S402). In this manner, the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B are formed.

  After forming the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B, the protective film 16 made of the above-described material is formed thereon (step S403). As a method for forming the protective film 16, a film forming method in which the energy of the film forming particles is small to such an extent that the protective film 16 is not affected, for example, a vapor deposition method or a CVD method is preferable. Further, it is desirable that the protective film 16 be performed continuously with the formation of the second electrode 15 without exposing the second electrode 15 to the atmosphere. This is because the red organic layer 14R, the green organic layer 14G, and the blue organic layer 14B can be prevented from being deteriorated by moisture and oxygen in the atmosphere. Further, in order to prevent a decrease in luminance due to deterioration of the red organic layer 14R, the green organic layer 14G, and the blue organic layer 14B, the film forming temperature of the protective film 16 is set to room temperature, and the protective film 16 is prevented from peeling off. Further, it is desirable to form the film under conditions that minimize the film stress.

  After that, the adhesive layer 20 is formed on the protective film 16, and the sealing substrate 30 is bonded with the adhesive layer 20 in between (step S404). Thus, the display device shown in FIG. 1 is completed.

  FIG. 12 schematically shows an example of a display device manufacturing system according to the manufacturing method shown in FIG. The manufacturing system 400 includes, for example, a hole injection layer / hole transport layer forming unit 410 that forms the hole injection layer 14A1 and the hole transport layer 14A2 on the substrate 11 on which the first electrode 12 and the insulating film 13 are formed, A batch transfer portion 420 that performs a batch transfer step, a blue monochrome layer / electron transport layer / second electrode forming portion 430 that forms the blue monochrome layer 14D, the electron transport layer 14E, and the second electrode 15, and a protective film 16 are formed. The protective film forming part 440 is arranged in a line. A transfer layer forming unit 450 that performs the transfer layer forming process described above is connected to the batch transfer unit 420. The transfer layer forming unit 450 selectively irradiates the red transfer layer 200R by irradiating the laser beam LB1 from the surface side of the base 110 and the red transfer layer forming unit 451 that forms the red transfer layer 200R on the entire surface side of the base 110. The transfer layer selective removing portion 452 to be removed and the green transfer layer forming portion 453 for forming the green transfer layer 200G on the entire surface side of the substrate 110 are arranged in a line. The arrangement of each part is not necessarily limited to a line shape, but may be another arrangement such as a radial shape.

In this display device, when a predetermined voltage is applied between the first electrode 12 and the second electrode 15, current is injected into the mixed layer 14RC, the green monochrome layer 14GC, and the blue monochrome layer 14D, and holes and Light emission occurs due to recombination with electrons. This light passes through the second electrode 15, the protective film 16 and the sealing substrate 30 and is extracted. At this time, in the red organic light emitting element 10R, the red organic layer 14R includes the mixed layer 14CR including the red light emitting material and the green light emitting material and the blue monochromatic layer 14D including the blue light emitting material, but has the lowest energy level. Energy transfer occurs in red, and red emission becomes dominant. In the green organic light emitting element 10G, the green organic layer 14G has a green monochromatic layer 14GC containing a green light emitting material and a blue monochromatic layer 14D containing a blue light emitting material, but energy transfer occurs in green having a lower energy level. The green light emission becomes dominant. In the blue light emitting element 10B, since the blue organic layer 14B has only the blue monochromatic layer 14D containing the blue light emitting material, blue light emission occurs.

  Thus, in this embodiment, since the red organic layer 14R has the mixed layer 14RC including the red light emitting material and the green light emitting material, the red transfer layer 200R and the green transfer layer are formed from the donor substrate 100 by the thermal transfer method. The mixed layer 14RC can be formed by a simple process of batch-transferring 200G.

  In addition, since the reflective layer 120 is provided on the donor substrate 100 in the region 100R1 where the red transfer layer is to be formed as viewed from the surface of the substrate 110, the donor substrate 100 is formed with the red transfer layer 200R on the entire surface of the substrate 100, and then the donor substrate 100 is formed. The red transfer layer 200R is selectively removed by arranging the substrate 100 and the substrate 11 so as to face each other and irradiating the laser beam LB1 from the surface side of the base 110, and the red transfer layer 200R remains only on the reflective layer 120. it can.

  Further, since the donor substrate 100 is provided with the reflective layer 120 in the non-transfer region 100NP as viewed from the back surface side of the base 110, the green transfer layer 200G is formed on the entire surface side of the base 110, and then the donor substrate 100 is formed. And the substrate 11 are opposed to each other, and the portion of the green transfer layer 200G other than the non-transfer region 100NP is selectively transferred to the substrate 11 by irradiating the laser beam LB2 from the back side of the base 110, and the non-transfer region 100NP. The portion can be left on the substrate 110 without being transferred.

  In addition, according to the manufacturing method or the manufacturing system of the display device of the present embodiment, the red transfer layer 200R and the green transfer layer 200G are formed on the donor substrate 100 and transferred onto the substrate 11 at once. The transfer for forming the red organic light emitting element 10R and the green organic light emitting element 10G can be performed at a time, and can be manufactured by a simple process.

  Furthermore, complicated steps such as the alignment, separation, and laser irradiation of the donor substrate 100 and the substrate 11 are reduced, the device configuration can be simplified, the device cost can be reduced, the tact time can be shortened, and the productivity can be reduced. Can be improved. Furthermore, since the number of times of transfer can be reduced, defects due to transfer can be reduced, and the donor substrate 100 for each color is not required, so that running costs can be reduced.

  In addition, the red transfer layer 200R and the green transfer layer 200G are re-formed by performing the transfer layer forming process again on the donor substrate 100 after the collective transfer process, and the collective transfer to another substrate 11 is performed. If the process is performed, a process and an apparatus for cleaning and reusing the donor substrate 100 after collective transfer become unnecessary, and the donor substrate 100 is used repeatedly without being discarded only once. be able to. Therefore, the apparatus configuration can be simplified, and the apparatus cost and the cost of the donor substrate can be further reduced.

  Furthermore, if the blue monochromatic layer 14D common to the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B is formed by a vapor deposition method after performing the collective transfer process, a conventional method is possible. Thus, it is not necessary to transfer three times as in the case of the number of emitted colors, and the number of times of transfer can be reduced to one.

(Modification)
FIG. 13 shows the configuration of the donor substrate according to the modification of the present invention in an unused state. In the donor substrate 100, the non-transfer region 100NP corresponds to a boundary region between the red organic light emitting element 10R and the green organic light emitting element 10G in the substrate 11. Thereby, in this donor substrate 100, the boundary between the mixed layer 14RC and the green monochromatic layer 14GC can be clearly formed in the collective transfer step, and the color mixture can be reliably suppressed. 13, in the donor substrate 100 in which the absorption layer 130 is formed on the entire surface side of the substrate 110 as shown in FIG. 4 and the reflection layer 120 is partially provided, the absorption layer 130 corresponding to the boundary region. In this example, a reflective layer 120 is additionally formed between the substrate 11 and the substrate 11.

  Note that the laminated structure of the reflective layer 120 and the absorbing layer 130 for providing the non-transfer region NP in the boundary region is as long as the reflective layer 120 is formed corresponding to the boundary region when viewed from the back side of the substrate 110. The laminated structure is not limited to those shown in FIG. For example, as shown in FIG. 14, a part of the absorption layer 130 may be removed corresponding to the boundary region 10 </ b> M and the region may be covered with the reflective layer 120. Further, in the donor substrate 100 in which the reflection layer 130 is formed on the entire surface side of the base 110 as shown in FIG. 5 and the absorption layer 130 is partially provided, the reflection layer 120 and the base are provided as shown in FIG. A part of the absorption layer 130 between 110 may be removed corresponding to the boundary region.

  While the present invention has been described with reference to the embodiment, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the above embodiment, the case of irradiating laser light in the transfer layer forming step and the batch transfer step has been described. However, for example, other radiation such as a lamp may be irradiated.

  In the above embodiment, the case where the reflective layer 120 and the absorption layer 130 are formed on the side of the base 110 facing the substrate 11 has been described. However, the reflection layer 120 and the absorption layer 130 satisfy the above-described conditions for the stacked configuration. As long as it is satisfied, the base 110 may be provided on the opposite side of the substrate 11. However, it is desirable to provide the base 110 on the side facing the substrate 11 because the accuracy of the formation position and transfer position of the red transfer layer 200R and the green transfer layer 200G is likely to increase.

  Further, for example, the material and thickness of each layer described in the above embodiment, or the film forming method, the film forming conditions, and the irradiation conditions of the laser beams LB1 and LB2 are not limited, and other materials and thicknesses may be used. Alternatively, other film forming methods, film forming conditions, and irradiation conditions may be used. For example, the first electrode 12 may be made of IZO (indium / zinc composite oxide) in addition to ITO. Moreover, you may comprise the 1st electrode 12 with a reflective electrode. In that case, the first electrode 12 has a thickness of, for example, 100 nm or more and 1000 nm or less, and it is desirable that the first electrode 12 has a reflectance as high as possible in order to increase the light emission efficiency. For example, the material constituting the first electrode 12 is a metal such as chromium (Cr), gold (Au), platinum (Pt), nickel (Ni), copper (Cu), tungsten (W), or silver (Ag). An elemental element or an alloy is mentioned. Further, for example, the first electrode 12 may have a dielectric multilayer film.

  In addition, for example, in the above embodiment, the first electrode 12, the organic layer 14, and the second electrode 15 are stacked on the substrate 11 in order from the substrate 11 side, and light is emitted from the sealing substrate 30 side. However, the second electrode 15, the organic layer 14, and the first electrode 12 are sequentially stacked on the substrate 11 from the substrate 11 side. It is also possible to extract light from the side.

  Furthermore, for example, in the above embodiment, the case where the first electrode 12 is an anode and the second electrode 15 is a cathode has been described. However, the anode and the cathode are reversed, and the first electrode 12 is the cathode and the second electrode. 15 may be an anode. Further, the first electrode 12 is a cathode, the second electrode 15 is an anode, and the second electrode 15, the organic layer 14, and the first electrode 12 are sequentially stacked on the substrate 11 from the substrate 11 side. It is also possible to extract light from the side.

  In addition, in the above-described embodiment, the configurations of the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B are specifically described. However, it is not necessary to include all the layers, Another layer may be further provided. For example, the first electrode 12 and the organic layer 14 are made of chromium oxide (III) (Cr2O3), ITO (Indium-Tin Oxide: indium (In) and tin (Sn) oxide mixed film), or the like. A thin film layer for hole injection may be provided.

  Furthermore, in the above embodiment, the second electrode 15 is constituted by a semi-transmissive electrode, and the light generated in the mixed layer 14RC, the green monochrome layer 14GC, and the blue monochrome layer 14D is extracted from the second electrode 15 side. As described above, the generated light may be extracted from the first electrode 12 side. In this case, it is desirable to increase the luminous efficiency so that the second electrode 15 has a reflectance as high as possible.

  DESCRIPTION OF SYMBOLS 10R ... Red organic light emitting element, 10G ... Green organic light emitting element, 10B ... Blue organic light emitting element, 11 ... Substrate, 12 ... 1st electrode, 13 ... Insulating film, 14R ... Red organic layer, 14G ... Green organic layer, 14B ... Blue organic layer, 14A1 ... hole injection layer, 14A2 ... hole transport layer, 14RC ... mixed layer, 14GC ... green monochromatic layer, 14D ... blue monochromatic layer, 14E ... electron transport layer, 15 ... second electrode, 16 ... protection Membrane, 20 ... Adhesive layer, 30 ... Substrate for sealing, 100 ... Donor substrate, 100R1 ... Red transfer layer formation planned area, 100NP ... Green transfer layer non-transfer area (non-transfer area), 110 ... Base, 120 ... Reflective layer 130 ... Absorbing layer, 200R ... Red transfer layer, 200G ... Green transfer layer, 300 ... Transparent substrate, 400 ... Manufacturing system

The present invention relates to a display equipment which includes a red organic light emitting element formed by thermal transfer method.

The present invention has been made in view of the above problems, its object is to provide a display equipment which includes a red organic light emitting element which can be formed by a simple process using a thermal transfer method.

In the display device according to the present invention , a mixed layer including a first electrode, a red light emitting material, a green light emitting material, a hole transporting material, an electron transporting material, and a charge transporting material is provided on a substrate. A red organic light emitting device having a red organic layer having a second electrode in order, a substrate, a first electrode, a green light emitting material, a hole transporting material, an electron transporting material, and a charge transporting material at least A green organic light emitting element including a green organic layer having a green monochromatic layer including one kind and a second electrode in order, a green light emitting material included in the green monochromatic layer, and a green light emitting material included in the mixed layer Are the same material .

In the display device according to the present invention, since the red organic layer has a mixed layer containing a red light emitting material and a green light emitting material, energy transfer occurs in red having a low energy level, and red light emission becomes dominant.

According to the display device of the present invention, since the red organic layer has the mixed layer containing the red light emitting material and the green light emitting material, the red transfer layer containing the red light emitting material and the green light emission from the donor substrate by the thermal transfer method. The mixed layer can be formed by a simple process of batch transferring the green transfer layer containing the material.

The red organic layer 14R has, for example, a configuration in which a hole injection layer 14A1, a hole transport layer 14A2, a mixed layer 14RC, a blue monochromatic layer 14D, and an electron transport layer 14E are stacked in this order from the first electrode 12 side. For example, the green organic layer 14G has a configuration in which a hole injection layer 14A1, a hole transport layer 14A2, a green monochrome layer 14GC, a blue monochrome layer 14D, and an electron transport layer 14E are stacked in this order from the first electrode 12 side. For example, the blue organic layer 14B has a configuration in which a hole injection layer 14A1, a hole transport layer 14A2, a blue monochromatic layer 14D, and an electron transport layer 14E are stacked in this order from the first electrode 12 side. Among these, the hole injection layer 14A1, the hole transport layer 14A2, the blue monochromatic layer 14D, and the electron transport layer 14E are common layers of the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B. The hole injection layer 14A1 is a buffer layer for improving hole injection efficiency and preventing leakage. The hole transport layer 14A2 is for increasing the hole transport efficiency to the mixed layer 14RC, the green monochromatic layer 14GC, and the blue monochromatic layer 14D, which are light emitting layers. The mixed layer 14RC, the green monochromatic layer 14GC, and the blue monochromatic layer 14D generate light by recombination of electrons and holes when an electric field is applied. The electron transport layer 14E is for increasing the efficiency of electron transport to the mixed layer 14RC, the green monochrome layer 14GC, and the blue monochrome layer 14D. Note that the hole injection layer 14A1, the hole transport layer 14A2, and the electron transport layer 14E may be provided as necessary, and may have different configurations depending on the emission color. An electron injection layer (not shown) made of LiF, Li2O, or the like may be provided between the electron transport layer 14E and the second electrode 15.

The second electrode 15 is composed of a transparent electrode or a semitransparent electrode, a mixed layer 14RC, the light generated by the green monochromatic layer 14GC, and the blue monochromatic layer 14 D so as to taken out from the second electrode 15 side Yes. For example, the second electrode 15 has a thickness of 5 nm or more and 50 nm or less, and is made of a simple substance or an alloy of a metal element such as aluminum (Al), magnesium (Mg), calcium (Ca), or sodium (Na). Among these, an alloy of magnesium and silver (MgAg alloy) is preferable.

The sealing substrate 30 is located on the second electrode 15 side of the red organic light emitting element 10R, the green organic light emitting element 10G, and the blue organic light emitting element 10B, and together with the adhesive layer 20, the red organic light emitting element 10R and the green organic light emitting element. The element 10G and the blue organic light emitting element 10B are sealed. Further, the sealing substrate 30, the mixed layer 14RC, for taking out the light generated in the green monochromatic layer 14GC, and the blue monochromatic layer 14 D from the second electrode 15 side, the red organic light emitting element 10R, the green organic light emitting element 10G, and a blue It is made of a material such as glass that is transparent to the light generated in the organic light emitting device 10B.

Note that the laminated structure of the reflective layer 120 and the absorbing layer 130 on the substrate 110 is not limited to the one shown in FIG. 4 as long as the above-described conditions are satisfied, and may be another laminated structure. For example, FIG. 4 shows a configuration in which the absorption layer 130 and the reflective layer 120 are partially provided on the entire surface side of the base 110, but as shown in FIG. The reflection layer 120 may be partially provided with the absorption layer 130.

After performing the batch transfer process, the donor substrate 100 is subjected to the transfer layer forming process (steps S201, S202, S203) described above again in order to re-form the red transfer layer 200R and the green transfer layer 200G. A batch transfer process is performed on the substrate 11. FIG. 10 shows a process of producing and regenerating such a donor substrate 100. On the unused donor substrate 100 shown in FIG. 10A, a red transfer layer 200R is formed on the entire surface side of the substrate 110 as shown in FIG. 10B (step S201). After selectively removing the red transfer layer 200R by irradiation with the laser beam LB1 as shown in FIG. 10C (step S202), the green transfer is performed on the entire surface side of the substrate 110 as shown in FIG. The layer 200G is formed (step S203). Next, a batch transfer process is performed as shown in FIG. 10E (step S300). At this time, the green transfer layer 200G remains in the non-transfer region 100NP of the donor substrate 100. Subsequently, as shown in FIG. 10F, a red transfer layer 200R is formed on the surface side of the substrate 110 while the green transfer layer 200G remains in the non-transfer region 100NP (step S201), and FIG. When the laser beam LB1 is irradiated as shown in C), the red transfer layer 200R can be selectively removed, and at the same time, the green transfer layer 200G remaining in the non-transfer region 100NP can be removed (step S202). After that, as shown in FIG. 10 (D), to form the green transfer layer 200G on the whole front surface of the substrate 110 (step S203). In this manner, a closed loop of the steps shown in FIGS. 10C to 10F can be configured, and a process or apparatus for cleaning and reusing the donor substrate 100 after batch transfer is unnecessary. In addition, the donor substrate can be used repeatedly without being discarded after being used once.

(Modification)
FIG. 13 shows the configuration of the donor substrate according to the modification of the present invention in an unused state. In the donor substrate 100, the non-transfer region 100NP corresponds to a boundary region between the red organic light emitting element 10R and the green organic light emitting element 10G in the substrate 11. Thereby, in this donor substrate 100, the boundary between the mixed layer 14RC and the green monochromatic layer 14GC can be clearly formed in the collective transfer step, and the color mixture can be reliably suppressed. 13, in the donor substrate 100 in which the absorption layer 130 is formed on the entire surface side of the substrate 110 as shown in FIG. 4 and the reflection layer 120 is partially provided, the absorption layer 130 corresponding to the boundary region. In this example, a reflective layer 120 is additionally formed between the substrate 110 and the substrate 110 .

Claims (6)

A red organic layer having a mixed layer including a first electrode, a red light emitting material and a green light emitting material, a hole transporting material, an electron transporting material, and a charge transporting material; A red organic light emitting device having two electrodes in order;
A green organic layer having a green monochromatic layer including at least one of the first electrode, a green light emitting material, a hole transporting material, an electron transporting material, and a charge transporting material; A green organic light emitting device having two electrodes in order,
The green light-emitting material contained in the green monochromatic layer and the green light-emitting material contained in the mixed layer are the same material. The display device according to claim 1, wherein the green light emitting material included in the green monochromatic layer and the green light emitting material included in the mixed layer have the same amount. The display device according to claim 1, wherein the red light emitting material is 2,6-bis [(4′-methoxydiphenylamino) styryl] -1,5-dicyanonaphthalene (BSN). The red light emitting material is 2,6-bis [(4′-methoxydiphenylamino) styryl] -1,5-dicyanonaphthalene (BSN),
The green light emitting material is Coumarin 6;
The at least 1 sort (s) among the said hole transport material, the said electron transport material, and both charge transport material is ADN (di (2-naphthyl) anthracene). Display device. A blue organic layer having a blue monochromatic layer including the first electrode, a blue light emitting material, a hole transporting material, an electron transporting material and at least one of both charge transporting materials on the substrate; A blue organic light emitting device having two electrodes in order,
The red organic layer has the blue monochromatic layer on the second electrode side of the mixed layer,
The display device according to claim 1, wherein the green organic layer has the blue monochrome layer on the second electrode side of the green monochrome layer. The display device according to claim 5, wherein the blue light emitting material is 4,4′-bis [2- {4- (N, N-diphenylamino) phenyl} vinyl] biphenyl (DPAVBi).

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