WO2021059459A1 - Organic el display device - Google Patents

Organic el display device Download PDF

Info

Publication number
WO2021059459A1
WO2021059459A1 PCT/JP2019/038017 JP2019038017W WO2021059459A1 WO 2021059459 A1 WO2021059459 A1 WO 2021059459A1 JP 2019038017 W JP2019038017 W JP 2019038017W WO 2021059459 A1 WO2021059459 A1 WO 2021059459A1
Authority
WO
WIPO (PCT)
Prior art keywords
barrier layer
organic
display device
layer
fine
Prior art date
Application number
PCT/JP2019/038017
Other languages
French (fr)
Japanese (ja)
Inventor
克彦 岸本
Original Assignee
堺ディスプレイプロダクト株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 堺ディスプレイプロダクト株式会社 filed Critical 堺ディスプレイプロダクト株式会社
Priority to PCT/JP2019/038017 priority Critical patent/WO2021059459A1/en
Publication of WO2021059459A1 publication Critical patent/WO2021059459A1/en

Links

Images

Classifications

    • HELECTRICITY
    • H10SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10KORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H10K59/80Constructional details
    • H10K59/87Passivation; Containers; Encapsulations
    • H10K59/873Encapsulations
    • H10K59/8731Encapsulations multilayered coatings having a repetitive structure, e.g. having multiple organic-inorganic bilayers
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09FDISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
    • G09F9/00Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
    • G09F9/30Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00Electroluminescent light sources
    • H05B33/02Details
    • H05B33/04Sealing arrangements, e.g. against humidity
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00Electroluminescent light sources
    • H05B33/12Light sources with substantially two-dimensional radiating surfaces
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05BELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B33/00Electroluminescent light sources
    • H05B33/12Light sources with substantially two-dimensional radiating surfaces
    • H05B33/22Light sources with substantially two-dimensional radiating surfaces characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers

Definitions

  • the present invention relates to an organic EL display device.
  • Organic EL (Electro Luminescence) display devices have begun to be put into practical use.
  • One of the features of the organic EL display device is that a flexible display device can be obtained.
  • the organic EL display device has at least one organic EL element (Organic Light Emitting Diode: OLED) for each pixel, and at least one TFT (Thin Film Transistor) that controls the current supplied to each OLED.
  • OLED Organic Light Emitting Diode
  • TFT Thin Film Transistor
  • the organic EL display device will be referred to as an OLED display device.
  • Such an OLED display device having a switching element such as a TFT for each OLED is called an active matrix type OLED display device.
  • the substrate on which the TFT and the OLED are formed is referred to as an element substrate.
  • OLEDs are liable to deteriorate under the influence of moisture and are liable to cause display unevenness.
  • Thin Film Encapsulation (TFE) technology has been developed as a technology for protecting the OLED from moisture and providing a sealing structure that does not impair flexibility.
  • the thin film sealing technique attempts to obtain sufficient water vapor barrier properties in a thin film by alternately laminating inorganic barrier layers and organic barrier layers. From the viewpoint of moisture resistance and reliability of the OLED display device, the WVTR (Water Vapor Transmission Rate) of the thin film sealing structure is typically required to be 1 ⁇ 10 -4 g / m 2 / day or less.
  • the TFE structure used in the OLED display devices currently on the market has an organic barrier layer (polymer barrier layer) having a thickness of about 5 ⁇ m to about 20 ⁇ m.
  • organic barrier layer polymer barrier layer
  • Such a relatively thick organic barrier layer also plays a role of flattening the surface of the device substrate.
  • a relatively thick organic barrier layer is formed, for example, by using an inkjet method.
  • the relatively thin organic barrier layer is discretely formed only around the convex portion (first inorganic barrier layer covering the convex portion) of the lower inorganic barrier layer (first inorganic barrier layer) of the organic resin film (organic barrier layer). It is sometimes called "solid part").
  • Patent Documents 1 and 2 describe the following methods.
  • a mist-like organic material for example, an acrylic monomer
  • the organic material condenses and drops on the substrate.
  • the droplet-like organic material moves on the substrate due to capillary action or surface tension, and is unevenly distributed at the boundary between the side surface of the convex portion of the first inorganic barrier layer and the surface of the substrate.
  • an organic resin film is formed at the boundary portion.
  • Patent Document 3 discloses a method of forming an organic resin film on a flat portion of an element substrate and then ashing to form an organic barrier layer having a plurality of discretely distributed solid portions. Has been done. For reference, all the disclosure contents of Patent Documents 1 to 3 are incorporated herein by reference.
  • the light utilization efficiency of the organic EL display device is lowered when the TFE structure is provided.
  • One of the causes is that a part of the light emitted from the OLED (light emitting layer) is reflected at the interface in the TFE structure.
  • Patent Documents 4 and 5 Various technologies have been developed to improve the light utilization efficiency of organic EL display devices. For example, in Patent Documents 4 and 5, a method of forming a concavo-convex structure on the surface of a substrate on which an OLED is formed and using this concavo-convex structure to form regular irregularities on the surface of an anode (reflecting electrode) of the OLED. Is disclosed. According to Patent Documents 4 and 5, the light utilization efficiency of the OLED can be improved by utilizing the surface plasmon resonance at the anode having regular irregularities.
  • Patent Document 4 describes that the height of the convex portion of the concave-convex structure is 10 nm or more and 500 nm or less, the width is 50 nm or more and 800 nm or less, and the interval (pitch) between adjacent convex portions is 100 nm or more and 1200 nm or less.
  • the height of the convex portion of the concave-convex structure is 100 nm or more and 800 nm or less
  • the width is 100 nm or more and 250 nm or less
  • the interval (pitch) between adjacent convex portions is 520 nm or more and 720 nm or less depending on the color of the pixel. It is described as (red), 435 nm or more and 635 nm or less (green), and 370 nm or more and 570 nm or less (blue).
  • Patent Documents 4 and 5 do not even mention the decrease in light utilization efficiency due to the TFE structure.
  • the present invention has been made to solve the above problems, and an object of the present invention is to provide an OLED display device that suppresses light reflection in a TFE structure.
  • An organic EL display device having a plurality of pixels. It has a substrate, an element substrate having a plurality of organic EL elements supported by the substrate, and a thin film sealing structure covering the plurality of organic EL elements.
  • the thin film sealing structure has a first inorganic barrier layer, an organic barrier layer formed on the first inorganic barrier layer, and a second inorganic barrier layer formed on the organic barrier layer.
  • the first inorganic barrier layer has a first sub-barrier layer and a second sub-barrier layer formed on the first sub-barrier layer and in contact with the organic barrier layer.
  • the surface of the first inorganic barrier layer in contact with the organic barrier layer has a plurality of fine convex portions, and the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and the plurality of fine convex portions.
  • An organic EL display device having a width of 20 nm or more and 80 nm or less.
  • the second sub-barrier layer has a plurality of discretely distributed island-shaped portions, and the plurality of island-shaped portions form the plurality of fine convex portions, according to any one of items 1 to 3.
  • Organic EL display device [Item 5] The organic EL display device according to any one of items 1 to 4, wherein the second sub-barrier layer is made of SiN or SiON.
  • the organic EL display device according to any one of items 1 to 6, wherein the first sub-barrier layer is an Al 2 O 3 layer having a thickness of 10 nm or more and 30 nm or less.
  • the first sub-barrier layer is a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
  • the second inorganic barrier layer includes a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
  • the element substrate further has a bank layer that defines each of the plurality of pixels.
  • the organic EL display device according to any one of items 1 to 9, wherein the organic barrier layer covers the bank layer and has a flat surface.
  • the organic EL display device according to item 10 wherein the thickness of the organic barrier layer is 3 ⁇ m or more and 10 ⁇ m or less.
  • the element substrate further has a bank layer that defines each of the plurality of pixels.
  • the bank layer has a slope that surrounds each of the plurality of pixels.
  • the organic barrier layer has a plurality of discretely distributed solid parts.
  • the first surface of the organic barrier layer in contact with the second inorganic barrier layer has a plurality of fine first convex portions, and the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the organic EL display device according to any one of items 1 to 13, wherein the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the organic EL display device according to item 14, wherein the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the second surface of the second inorganic barrier layer which is opposite to the surface in contact with the first surface, has a plurality of fine second convex portions, and the height of the plurality of fine second convex portions.
  • the organic EL display device according to item 13, wherein the width and the interval are independently 20 nm or more and 80 nm or less.
  • an OLED display device that suppresses light reflection in a TFE structure is provided.
  • FIG. 5 is a partial cross-sectional view of a TFE structure 10A included in the OLED display device according to the first embodiment of the present invention. It is a partial cross-sectional view of the TFE structure 10B included in the OLED display device according to Embodiment 2 of this invention. It is a top view which shows typically the structure of the OLED display device 100 by embodiment of this invention. It is a schematic cross-sectional view of the OLED display device 100A1 of Embodiment 1 provided with a TFE structure 10A1, and is the cross-sectional view including the pixel Pix along the line 4A-4A'in FIG.
  • FIG. 5 is a schematic cross-sectional view of the OLED display device 100A2 of the first embodiment including the TFE structure 10A2, and is a cross-sectional view including a pixel Pix along the 4A-4A'line in FIG.
  • FIG. 5 is a schematic cross-sectional view showing an interface between the organic barrier layers 14A and 14B and the second inorganic barrier layer 16 and the surface 16S of the second inorganic barrier layer 16 in the TFE structure 10B (10B1, 10B2).
  • the OLED display device according to the embodiment of the present invention and the manufacturing method thereof will be described with reference to the drawings.
  • the embodiments of the present invention are not limited to the embodiments exemplified below.
  • the organic EL display device according to the embodiment of the present invention may have, for example, a glass substrate instead of the flexible substrate.
  • FIG. 1 is a schematic partial cross-sectional view of an active region of the OLED display device 100 according to the embodiment of the present invention
  • FIGS. 2A and 2B are partial cross-sectional views of a TFE structure 10 formed on the OLED 3.
  • FIG. 2A is a partial cross-sectional view of the TFE structure 10A included in the OLED display device according to the first embodiment
  • FIG. 2B is a partial cross-sectional view of the TFE structure 10B included in the OLED display device according to the second embodiment.
  • the OLED display device 100 has a plurality of pixels, and each pixel has at least one organic EL element (OLED).
  • OLED organic EL element
  • the OLED display device 100 includes a flexible substrate (hereinafter, may be simply referred to as a “board”) 1, a circuit (backplane) 2 including a TFT formed on the substrate 1, and a circuit. It has an OLED 3 formed on the OLED 3 and a TFE structure 10 formed on the OLED 3.
  • OLED3 is, for example, a top emission type.
  • the uppermost portion of the OLED 3 is, for example, an upper electrode or a cap layer (refractive index adjusting layer).
  • An optional polarizing plate 4 is arranged on the TFE structure 10.
  • the substrate 1 is, for example, a polyimide film having a thickness of 15 ⁇ m.
  • the thickness of the circuit 2 including the TFT is, for example, 4 ⁇ m
  • the thickness of the OLED 3 is, for example, 1 ⁇ m
  • the thickness of the TFE structure 10 is, for example, 1.5 ⁇ m or less.
  • FIG. 2A is a partial cross-sectional view of the TFE structure 10A included in the OLED display device according to the first embodiment.
  • the TFE structure 10A was formed on the first inorganic barrier layer (for example, SiN layer) 12, the organic barrier layer (for example, acrylic resin layer) 14 formed on the first inorganic barrier layer 12, and the organic barrier layer 14. It has a second inorganic barrier layer (for example, SiN layer) 16.
  • the first inorganic barrier layer 12 is formed directly above the OLED 3.
  • the organic barrier layer 14 may be relatively thick and also serve as a flattening layer (see FIG. 4A), or may have a plurality of relatively thin and discretely distributed solid parts (see FIG. 5A). ..
  • the organic barrier layer 14 is preferably formed of a colorless and transparent photocurable resin (for example, acrylic resin or epoxy resin), and for example, when the thickness is 1 ⁇ m, the transmittance of visible light is 95% or more. Is preferable.
  • the refractive index of the photocurable resin is, for example, about 1.48 to about 1.61.
  • the light that has passed through the TFE structure 10A is emitted from the OLED display device 100 and used for display.
  • a part of the light incident on the TFE structure 10A is reflected at the interface between the first inorganic barrier layer 12 and the organic barrier layer 14.
  • the refractive index of the SiN layer is 1.85
  • the refractive index of the acrylic resin layer is 1.54
  • the refractive index difference ( ⁇ n) is as large as 0.31 or more. Therefore, the light emitted from the OLED 3 is reflected at the interface between the first inorganic barrier layer 12 and the organic barrier layer 14, resulting in loss.
  • the first inorganic barrier layer 12 of the TFE structure 10A included in the OLED display device according to the first embodiment of the present invention is formed on the first sub-barrier layer 12sa and the first sub-barrier layer 12sa, and is in contact with the organic barrier layer 14.
  • the surface 12S having the layer 12sb and in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine protrusions, and the height of the plurality of fine protrusions is 20 nm or more and 80 nm or less.
  • the width of the plurality of fine convex portions is 20 nm or more and 80 nm or less (see FIG. 7A).
  • the OLED display device can realize higher light utilization efficiency than before.
  • a structure (convex portion) finer than the wavelength of visible light is formed on the surface of an object and air is filled between the fine structures, a region in which a fine structure containing air is formed.
  • the average refractive index (effective refractive index) of (layer) is smaller than the refractive index of the substance itself constituting the fine structure.
  • the horizontal cross-sectional area of the microstructure is gradually increased with respect to the height direction of the microstructure so that the average refractive index is gradually changed from the air to the bottom of the microstructure, air and an object can be obtained. It is known that the sudden change in the refractive index at the interface with the light can be eliminated and the reflection of light can be reduced.
  • the above-mentioned object corresponds to the first sub-barrier layer 12sa, and the surface roughness of the first sub-barrier layer 12sa is less than 5 nm.
  • convex portions (second sub-barrier layer 12sb) having a height of 20 nm or more and 80 nm or less and a width of 20 nm or more and 80 nm or less are formed discretely as a microstructure.
  • the lower limit of the height of the second sub-barrier layer 12sb is more preferably 40 nm or more.
  • the upper limit of the height of the second sub-barrier layer 12sb is higher than the lower limit wavelength of visible light. It is preferably 80 nm or less, which is sufficiently small.
  • the substance constituting the second sub-barrier layer 12sb is preferably SiN or SiON, and these refractive indexes are about 1.7 to 2.1, although it depends on the film forming method.
  • the refractive index when the SiN layer is formed by the PECVD (Plasma Enhanced Chemical Vapor Deposition) method at a substrate temperature of 100 ° C. or lower is about 1.85.
  • the material constituting the first sub-barrier layer 12sa may be the same as or different from that of the second sub-barrier layer 12sb.
  • the thickness of the first sub-barrier layer 12sa is preferably at least 200 nm or more when a SiN film or a SiON film is used in order to ensure moisture resistance reliability for the organic EL element.
  • the thickness may be 10 nm or more and 30 nm or less.
  • air is not filled between the plurality of fine protrusions, but a resin material (typically having a refractive index of about 1.5) constituting the organic barrier layer is filled. Is preferable. Refraction between the air and the materials that make up the protrusions when air is filled between the plurality of fine protrusions, or at least when air is present between the organic barrier layer and the plurality of fine protrusions. Since the rate difference is too large, even if the height of the convex portion is set to 20 nm or more and 80 nm or less, reflection may not be sufficiently suppressed.
  • a resin material typically having a refractive index of about 1.5
  • each convex portion of the second sub-barrier layer 12sb (the cross-sectional shape on the surface including the height direction (that is, the surface perpendicular to the substrate)) is a parabolic shape
  • the surface that is, the surface orthogonal to the height direction of the convex portion. That is, the cross-sectional area (the cross-sectional shape is almost circular) of the convex portion on the surface parallel to the substrate surface changes linearly along the height direction, and as a result, the average refractive index is the highest along the height direction. It can be changed slowly. Therefore, when forming a convex portion having a specific height, the reflectance can be most effectively reduced by making the cross-sectional shape (the surface including the height direction) a parabolic shape.
  • the plurality of fine protrusions do not necessarily have to have a periodic structure. However, if there is a portion having a width equal to or more than the wavelength of light even in at least a part of the plurality of fine convex portions, light reflection (scattering) occurs in that portion. It is not preferable because it is visually recognized as uneven display on the OLED display device. Therefore, the plurality of fine convex portions may have different heights and widths, but it is preferable that all of them are included in the range of 20 nm or more and 80 nm or less.
  • the present inventor has not only the height and width of the plurality of fine protrusions, but also the distance between the plurality of fine protrusions (adjacent fine protrusions). It was found that it is effective to make the interval between them sufficiently small with respect to the wavelength of visible light (400 nm or more and 700 nm or less). That is, it is preferable that the distance between the plurality of fine protrusions is also 20 nm or more and 80 nm or less.
  • the spacing between the plurality of fine protrusions (second sub-barrier layer 12sb), in other words, the width of the flat portion where the surface of the first sub-barrier layer 12sa is exposed is one-fifth of the lower limit of the wavelength of visible light of 400 nm. If it exceeds 80 nm, non-negligible reflection may occur in the flat portion.
  • the height and width of each of the plurality of fine protrusions and the distance between the adjacent fine protrusions are independently in the range of 20 nm or more and 80 nm or less. Is preferable.
  • reflection on the surface of the first inorganic barrier layer (the top and side surfaces of the second sub-barrier layer 12sb, and the flat surface where the surface of the first sub-barrier layer 12sa is exposed) can be effectively suppressed. it can.
  • a method using a dielectric multilayer structure in which dielectric layers having a high refractive index and dielectric layers having a low refractive index are alternately laminated is also known.
  • this dielectric multilayer structure utilizes interference, it effectively reduces the reflection of light (typically vertically incident light) that is incident on the interface at a particular angle (determined by design).
  • the effect of reducing the reflection of light incident at other angles is limited.
  • the reflection of light of a specific wavelength (determined by design) can be effectively reduced, but the effect of reducing the reflection of light of other wavelengths is limited.
  • a high antireflection effect can be obtained for light having a wide incident angle and for light having a wide wavelength range.
  • the width of the plurality of fine convex portions is smaller than 20 nm, an elongated convex portion having a large aspect ratio (height / width) will be formed, which increases manufacturing difficulty. In particular, it is difficult to form such an elongated convex portion by the PECVD method. Therefore, the width of the plurality of fine protrusions is preferably 20 nm or more.
  • a method for forming a porous low refractive index film by a sol-gel method or a molding method using a mold is used for minute particles.
  • a method of forming a row of protrusions a method of forming a fine structure by patterning by irradiation with a laser beam, and the like.
  • the PECVD method is preferable from the viewpoint of mass productivity because the first sub-barrier layer 12sa and the second sub-barrier layer 12sb can be continuously formed as described later.
  • a part of the light incident on the TFE structure 10A is also reflected at the interface between the organic barrier layer 14 and the second inorganic barrier layer 16.
  • an optical film such as a polarizing plate or a touch panel layer may be arranged via an adhesive layer (including an adhesive layer). Since the adhesive layer is made of a polymer material having a refractive index of about 1.5, even at the interface between the second inorganic barrier layer 16 and the adhesive layer, due to the difference in refractive index between these layers, OLED3 Part of the light emitted from is reflected.
  • the protective glass or the like is arranged so as to cover the second inorganic barrier layer 16 with the air layer interposed therebetween, the light emitted from the OLED 3 on the surface of the second inorganic barrier layer (the interface with the air layer). Part of is reflected.
  • the first surface 14S in contact with the second inorganic barrier layer 16 of the organic barrier layer 14 has a plurality of fine first convex portions.
  • the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less, and the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less (see FIG. 9).
  • the interval between the plurality of fine first convex portions is also preferably 20 nm or more and 80 nm or less.
  • the OLED display device according to the second embodiment of the present invention can realize a higher light utilization efficiency than the OLED display device according to the first embodiment.
  • the second surface of the second inorganic barrier layer 16 is affected by a plurality of fine first convex portions (surface roughness) of the first surface 14S of the organic barrier layer 14, and has a plurality of fine second convex portions. Can be done. However, when the height of the plurality of fine first convex portions of the first surface 14S of the organic barrier layer 14 is small, the height of the plurality of fine second convex portions of the second surface 16S of the second inorganic barrier layer 16 is small. The height can be less than 20 nm.
  • a sub-barrier layer forming a convex portion may be formed on the second surface of the second inorganic barrier layer 16.
  • the second surface 16S of the second inorganic barrier layer 16 has a plurality of fine second convex portions, and the plurality of fine second convex portions.
  • the height of the second convex portion may be 20 nm or more and 80 nm or less, and the width of the plurality of fine second convex portions may be 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions can be 20 nm or more and 80 nm or less. Since the second surface 16S of the second inorganic barrier layer 16 has such a plurality of fine second convex portions, reflection on the second surface 16S of the second inorganic barrier layer 16 is also reduced.
  • the adhesive layer is formed. It is preferable that the gap between the plurality of fine second convex portions is filled. With such a configuration, the change in the average refractive index between the second inorganic barrier layer 16 and the adhesive layer can be made slower than when air is filled, so that the second surface can be made gentler. The reflection at 16S can be reduced more effectively.
  • the second inorganic barrier layer 16 of the organic barrier layer 14 does not have to be provided with a plurality of fine protrusions of the surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 in the OLED display device according to the first embodiment. If the first surface 14S in contact with the surface has the above-mentioned fine protrusions, at least the reflection at the interface between the organic barrier layer 14 and the second inorganic barrier layer 16 is reduced, so that the light utilization efficiency is higher than before. It can be realized.
  • FIG. 3 shows a schematic plan view of the OLED display device 100 according to the embodiment of the present invention. Both the OLED display devices of the first embodiment and the second embodiment may have the same planar structure as the OLED display device 100.
  • the OLED display device 100 comprises a flexible substrate 1, a circuit (backplane) 2 formed on the flexible substrate 1, a plurality of OLEDs 3 formed on the circuit 2, and a TFE structure 10 formed on the OLED 3. Have.
  • the layer in which a plurality of OLEDs 3 are arranged may be referred to as an OLED layer 3.
  • the circuit 2 and the OLED layer 3 may share some components.
  • An optional polarizing plate (see reference numeral 4 in FIG. 1) may be further arranged on the TFE structure 10. Further, for example, a layer having a touch panel function may be arranged between the TFE structure 10 and the polarizing plate. That is, the OLED display device 100 can be modified into an on-cell type display device with a touch panel.
  • the circuit 2 has a plurality of TFTs (not shown), and a plurality of gate bus lines (not shown) and a plurality of source bus lines (not shown), each of which is connected to any of the plurality of TFTs (not shown).
  • the circuit 2 may be a known circuit for driving a plurality of OLEDs 3.
  • the plurality of OLEDs 3 are connected to any of the plurality of TFTs included in the circuit 2.
  • the OLED 3 may also be a known OLED.
  • the OLED display device 100 further includes a plurality of terminals 38 arranged in a peripheral region R2 outside the active region (area surrounded by a broken line in FIG. 3) R1 in which the plurality of OLEDs 3 are arranged, and a plurality of terminals.
  • the TFE structure 10 has a plurality of leader wires 30 connecting the 38 with any of the plurality of gate bus lines or the plurality of source bus lines, and the TFE structure 10 is on the plurality of OLEDs 3 and the active region R1 of the plurality of leader wires 30. It is formed on the side part.
  • the TFE structure 10 covers the entire active region R1 and is selectively formed on the portion of the plurality of drawer wirings 30 on the active region R1 side, and the terminal 38 side and the terminal 38 of the drawer wiring 30 are formed. , Not covered by TFE structure 10.
  • drawer wiring 30 and the terminal 38 are integrally formed by using the same conductive layer, but they may be formed by using different conductive layers (including a laminated structure).
  • FIGS. 4A, 4B, and 4C the structure of the OLED display device 100A1 according to the first embodiment, which includes the TFE structure 10A1 having a relatively thick organic barrier layer 14A, will be described.
  • 4A is a cross-sectional view including the pixel Pix along the 4A-4A'line in FIG. 3
  • FIG. 4B is a cross-sectional view including the particles P along the 4A-4A' line in FIG. 3C. Is a cross-sectional view taken along the line 4C-4C'in FIG.
  • the thin film sealing structure 10A1 has a first inorganic barrier layer 12, an organic barrier layer 14A formed on the first inorganic barrier layer 12, and a second formed on the organic barrier layer 14A. It has an inorganic barrier layer 16.
  • the organic barrier layer 14A has a relatively thick and flat surface.
  • the element substrate 20 of the OLED display device 100A1 further has a bank layer 48 that defines each of the plurality of pixels Pix.
  • the bank layer 48 is formed of an insulating material, and is formed between the lower electrode 42 of the OLED 3 and the organic layer (organic EL layer) 44.
  • the OLED 3 includes a lower electrode 42, an organic layer 44 formed on the lower electrode 42, and an upper electrode 46 formed on the organic layer 44, and the lower electrode 42 and the upper electrode 46 are, for example, anodes, respectively. And constitutes the cathode.
  • the upper electrode 46 is a common electrode formed over the entire pixel in the active region, and the lower electrode (pixel electrode) 42 is formed for each pixel.
  • the bank layer 48 If the bank layer 48 is present between the lower electrode 42 and the organic layer 44, holes are not injected from the lower electrode 42 into the organic layer 44. Therefore, since the region where the bank layer 48 exists does not function as the pixel Pix, the bank layer 48 defines the outer edge of the pixel Pix.
  • the bank layer 48 is sometimes called a PDL (Pixel Defining Layer).
  • the bank layer 48 has an opening corresponding to the pixel Pix, and the side surface of the opening has a slope having a forward taper side surface portion TSF.
  • the slope of the bank layer 48 surrounds each pixel.
  • the bank layer 48 is formed using, for example, a photosensitive resin (for example, polyimide or acrylic resin).
  • the thickness of the bank layer 48 is, for example, 1 ⁇ m or more and 2 ⁇ m or less.
  • the inclination angle ⁇ b of the slope of the bank layer 48 is 60 ° or less. If the inclination angle ⁇ b of the slope of the bank layer 48 is more than 60 °, defects may occur in the layer located above the bank layer 48.
  • the organic barrier layer 14A covers the bank layer 48 and has a flat surface.
  • the thickness of the organic barrier layer 14A is larger than the thickness of the bank layer 48, for example, 3 ⁇ m or more and 20 ⁇ m or less.
  • the second inorganic barrier layer 16 is formed on the flat surface of the organic barrier layer 14A.
  • the thickness of the organic barrier layer 14A may be 3 ⁇ m or more and 10 ⁇ m or less.
  • a resin material having a relatively high viscosity is required. The highly viscous resin material may not fill the gaps between the plurality of fine protrusions of the first inorganic barrier layer 12.
  • the thickness of the organic barrier layer 14A is 3 ⁇ m or more and 10 ⁇ m or less, it can be formed of a resin material having a relatively low viscosity. Can be filled in.
  • the organic barrier layer 14A having such a thickness can be formed by, for example, an inkjet method or a slit coating method.
  • the first inorganic barrier layer 12 has a first sub-barrier layer 12sa and a second sub-barrier layer 12sb formed on the first sub-barrier layer 12sa and in contact with the organic barrier layer 14.
  • the surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine convex portions, and the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and a plurality of fine protrusions are formed.
  • the width of the fine convex portion is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine protrusions is 20 nm or more and 80 nm or less.
  • the second sub-barrier layer 12sb has a plurality of discretely distributed island-shaped portions, and even if the plurality of island-shaped portions form the plurality of fine convex portions. Good.
  • the second sub-barrier layer 12sb is made of, for example, SiN or SiON.
  • the refractive index of SiN or SiON is preferably 1.70 or more and 2.10 or less.
  • the surface roughness of the first sub-barrier layer 12sa (for example, arithmetic mean roughness Ra (according to JIS)) is, for example, less than 5 nm.
  • the first sub-barrier layer 12sa is, for example, an Al 2 O 3 layer having a thickness of 10 nm or more and 30 nm or less.
  • the first sub-barrier layer 12sa may be, for example, a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
  • the second inorganic barrier layer 16 is, for example, a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
  • the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are selectively formed only in a predetermined region so as to cover the active region R1 by, for example, a PECVD method using a mask.
  • the organic barrier layer 14A is formed only in the region surrounded by the inorganic barrier layer joint where the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact with each other. Therefore, the organic barrier layer 14A serves as an intrusion route for moisture, and the moisture does not reach the active region R1 of the OLED display device.
  • the organic barrier layer 14A is formed of a colorless and transparent photocurable resin (for example, an acrylic resin or an epoxy resin) in a predetermined region by using, for example, an inkjet method.
  • the refractive index of the acrylic resin is, for example, 1.48 or more and 1.55 or less.
  • the refractive index of the epoxy resin is, for example, 1.55 or more and 1.61 or less.
  • the presence of particles (typically 0.5 ⁇ m or more and 5 ⁇ m or less) P in the active region R1 before or during the formation of the first inorganic barrier layer 12 is schematically shown in FIG. 4B.
  • cracks (defects) 12c may be formed in the first inorganic barrier layer 12. It is considered that this is caused by the collision (impingement) between the first inorganic barrier layer 12a growing from the surface of the particles P and the first inorganic barrier layer 12b growing from the flat portion of the surface of the OLED 3.
  • the presence of such cracks 12c reduces the barrier property of the TFE structure.
  • the TFE structure 10A1 can suppress a decrease in barrier property.
  • FIG. 4C is a cross-sectional view taken along the line 4C-4C'in FIG. 3, and is a cross-sectional view of a portion 32 of the drawer wiring 30 on the active region R1 side.
  • the organic barrier layer 14A is formed only in the active region (region surrounded by the broken line in FIG. 2) R1 in the TFE structure 10 in FIG. 3, and is not formed outside the active region R1. Therefore, outside the active region R1, the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact with each other. That is, as described above, the organic barrier layer 14A is surrounded by the inorganic barrier layer joint portion in which the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact with each other. Therefore, as shown in FIG. 4C, the portion 32 of the drawer wiring 30 on the active region R1 side is covered with the first inorganic barrier layer 12 and the second inorganic barrier layer 16.
  • FIGS. 5A, 5B and 5C which comprises a TFE structure 10A2 having a relatively thin organic barrier layer 14B.
  • 5A is a cross-sectional view including the pixel Pix along the 4A-4A'line in FIG. 3
  • FIG. 5B is a cross-sectional view including the particles P along the 4A-4A' line in FIG. 3C. Is a cross-sectional view taken along the line 4C-4C'in FIG.
  • the organic barrier layer 14B of the TFE structure 10A2 shown in FIG. 5A has a plurality of discretely distributed solid parts.
  • the plurality of solid portions have a pixel peripheral solid portion 14Ba extending from the slope of the first inorganic barrier layer 12 on the side surface of the opening of the bank layer 48 to the periphery within the pixel Pix.
  • the thickness of the organic barrier layer 14B (here, the thickness of the solid portion 14Ba around the pixel) is preferably 50 nm or more and less than 200 nm. When the thickness of the solid portion 14Ba around the pixel increases, the discretely dispersed solid portion becomes a continuous film.
  • the OLED display device 100A2 having a solid portion in which the organic barrier layer 14B is discretely dispersed has an advantage that it is superior in flexibility to the OLED display device 100A having a relatively thick organic barrier layer 14A.
  • the solid portion 14Bb is formed so as to fill the cracks 12c of the first inorganic barrier layer 12, and the surface of the solid portion 14Bb is on the particles P.
  • the surface of the first inorganic barrier layer 12a and the surface of the first inorganic barrier layer 12b on the flat portion of the OLED 3 are continuously and smoothly connected. Since the organic barrier layer 14B is formed by curing a liquid photocurable resin, a concave surface is formed by surface tension. At this time, the photocurable resin exhibits good wettability with respect to the first inorganic barrier layer 12. If the photocurable resin has poor wettability with respect to the first inorganic barrier layer 12, it may become convex on the contrary.
  • the organic barrier layer 14 may also be thinly formed on the surface of the first inorganic barrier layer 12a on the particles P.
  • the solid portion 14Bb having a concave surface continuously and smoothly connects the surface of the first inorganic barrier layer 12a on the particles P and the surface of the first inorganic barrier layer 12b on the flat portion.
  • the second inorganic barrier layer 16 can be formed with a dense film without defects.
  • the organic barrier layer 14B can maintain the barrier property of the TFE structure 10A2 even in the presence of the particles P.
  • FIG. 5C is a cross-sectional view taken along the line 4C-4C'in FIG. 3, and is a cross-sectional view of a portion 32 of the leader wiring 30 on the active region R1 side.
  • the organic barrier layer 14B includes a solid portion 14Bc formed around a convex portion on the surface of the first inorganic barrier layer 12 that reflects the cross-sectional shape of the portion 32 of the lead-out wiring 30. Due to the presence of the solid portion 14Bc, the second inorganic barrier layer 16 can be formed on the step of the first inorganic barrier layer 12 with a dense film having no defects.
  • the organic barrier layer 14B can be formed, for example, by the method described in Patent Document 1 or 2 above.
  • a vapor or atomized organic material eg, acrylic monomer
  • an element substrate maintained at a temperature below room temperature and condensed on the element substrate to form a liquid capillary tube of the organic material. Due to the phenomenon or surface tension, the first inorganic barrier layer 12 is unevenly distributed at the boundary between the side surface of the convex portion and the flat portion.
  • a solid portion of the organic barrier layer (for example, an acrylic resin layer) 14B is formed at the boundary portion around the convex portion.
  • the organic barrier layer 14B formed by this method has substantially no solid portion in the flat portion.
  • the viscosity of the photocurable resin, the wettability with respect to the slope, and the like are controlled so that the liquid film is also formed on the slope of the bank layer 48.
  • the surface of the slope may be modified.
  • the thickness of the resin layer to be first formed is adjusted (for example, less than 100 nm), and / or the ashing conditions (including time) are adjusted. It is also possible to form the organic barrier layer 14B.
  • an inorganic barrier layer joint portion in which the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact is formed in a part of the TFE structure 10A2 formed on the drawer wiring 30.
  • the taper angle of the lead wire 30 is set to 70 ° or less, or the photocurable resin is vaporized by irradiating infrared rays or the like until the photocurable resin is cured. You can let them do it.
  • the organic barrier layer 14B may be formed by using, for example, a spray method, a spin coating method, a slit coating method, screen printing or an inkjet method. An ashing step may be further included.
  • the organic barrier layer may be formed by using a photosensitive resin and mask exposure may be performed. By mask exposure, a solid portion 14Ba around the pixel may be formed, and an inorganic barrier layer joint portion in which the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact may be formed.
  • FIG. 6A shows a schematic cross-sectional view of the TFE structure 10A1 in the OLED display device 100A1
  • FIG. 6B shows a schematic cross-sectional view of the TFE structure 10A2 in the OLED display device 100A2.
  • the relatively thick organic barrier layer 14A of the TFE structure 10A1 shown in FIG. 6A covers the bank layer 48 and has a flat surface.
  • the surface 12S of the first inorganic barrier layer 12 in contact with the organic barrier layer 14A has a plurality of fine protrusions.
  • the relatively thin organic barrier layer 14B of the TFE structure 10A2 shown in FIG. 6B has a plurality of discretely distributed solid portions from the slope of the first inorganic barrier layer 12 on the side surface of the opening of the bank layer 48. It has a pixel peripheral solid portion 14Ba that extends to the periphery within the pixel Pix.
  • the surface 12S in contact with the organic barrier layer 14B of the first inorganic barrier layer 12 has a plurality of fine protrusions.
  • the first inorganic barrier layer 12 has a first sub-barrier layer 12sa and a second sub-barrier layer 12sb formed on the first sub-barrier layer 12sa and in contact with the organic barrier layer 14.
  • the surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine convex portions, the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and the plurality of fine convex portions.
  • the width of is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine protrusions is 20 nm or more and 80 nm or less.
  • the second sub-barrier layer 12sb may have a plurality of discretely distributed island-shaped portions, and the plurality of island-shaped portions may form the plurality of fine convex portions.
  • the surface 12S of the first inorganic barrier layer 12 includes the surface of a plurality of discretely distributed island-shaped portions of the second sub-barrier layer 12sb and the second sub-barrier layer 12sb among the surfaces of the first sub-barrier layer 12sa. It will be composed of a plurality of constituent island-shaped portions that are not formed.
  • the first sub-barrier layer 12sa is, for example, an Al 2 O 3 layer (alumina layer) having a thickness of 10 nm or more and 30 nm or less.
  • a dense film-like Al 2 O 3 layer having excellent barrier properties can be obtained by forming it by the ALD (Atomic Layer Deposition) method.
  • the first sub-barrier layer 12sa may be a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
  • the SiN layer or the SiON layer can be formed by the PECVD method. When formed in this way, the refractive index of SiN or SiON is 1.70 or more and 2.10 or less.
  • the second sub-barrier layer 12sb is formed of, for example, SiN or SiON.
  • the second sub-barrier layer 12sb can also be formed by the PECVD method.
  • the first sub-barrier layer 12sa is formed of the SiN layer or the SiON layer
  • the first sub-barrier layer 12sa and the second sub-barrier layer 12sb can be continuously formed by the PECVD method, so that the throughput is increased and the manufacturing cost is increased. Can be reduced.
  • the first sub-barrier layer 12sa is formed and then distributed discretely by increasing the film forming speed and / or adjusting the film forming temperature (element substrate temperature).
  • a second sub-barrier layer 12sb having a plurality of island-shaped portions can be obtained.
  • the temperature may be raised or lowered so as to deviate from the appropriate element substrate temperature, but in consideration of the thermal effect on the organic EL device, the temperature is lowered. It is preferable to adjust with.
  • the oxygen concentration to be supplied may be increased.
  • the first sub-barrier layer 12sa which is dense and has a high barrier property
  • the second sub-barrier layer 12sb which has a plurality of discretely distributed island-shaped portions, can be formed with desired thicknesses. Compared with the case where the density of the light is continuously changed, it is possible to secure the reliability of moisture resistance and suppress the reflection of light more reliably.
  • the surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine convex portions, the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and the plurality of fine convex portions.
  • the width of is 20 nm or more and 80 nm or less.
  • the distance between the plurality of fine protrusions is 20 nm or more and 80 nm or less.
  • the plurality of fine convex portions having such a configuration and the flat portions between them are sufficiently small even with respect to the lower limit region of visible light (about 400 nm) and do not reflect light. Further, since the organic barrier layer having a refractive index smaller than that is filled between the plurality of fine convex portions, the average refractive index can be gradually lowered. Therefore, the reflection caused by the refractive index can be reduced or eliminated.
  • the OLED display device 100A1 and the OLED display device 100A2 according to the first embodiment have a region in which the second inorganic barrier layer 16 is directly formed on the first inorganic barrier layer 12. If the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are made of the same material, light will not be reflected at the interface between the first inorganic barrier layer 12 and the second inorganic barrier layer 16. Even when the first sub-barrier layer 12sa is formed of the Al 2 O 3 layer and the second sub-barrier layer 12 sb is formed of the SiN layer or the SiON layer, the refractive index of Al 2 O 3 is about 1.80.
  • the refractive index of SiN is about 1.85 as described above, there is almost no difference in the refractive index and the reflection at the interface is very small. Therefore, since the plurality of fine convex portions act on the organic barrier layer having a smaller refractive index to gradually lower the average refractive index, the reflection caused by the refractive index can be reduced or eliminated.
  • the thickness of the second inorganic barrier layer 16 can be increased. 200 nm or more, more preferably 300 nm or more larger than the height of the fine convex portion on the surface of the first inorganic barrier layer 12 (for example, when the height of the convex portion is 80 nm, the thickness of the second inorganic barrier layer 16 is increased.
  • the diameter By setting the diameter to 380 nm or more), a TFE structure having a good barrier property can be obtained without lowering the barrier property of the second inorganic barrier layer 16 against water and oxygen.
  • FIG. 8A shows a schematic cross-sectional view of the TFE structure 10B1 in the OLED display device 100B1
  • FIG. 8B shows a schematic cross-sectional view of the TFE structure 10B2 in the OLED display device 100B2.
  • the relatively thick organic barrier layer 14A of the TFE structure 10B1 shown in FIG. 8A covers the bank layer 48 and has a flat surface.
  • the surface 12S of the first inorganic barrier layer 12 in contact with the organic barrier layer 14A has a plurality of fine protrusions.
  • the first surface 14AS in contact with the second inorganic barrier layer 16 of the organic barrier layer 14A has a plurality of fine first convex portions, and the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the second surface 16S of the second inorganic barrier layer 16 has a plurality of fine second convex portions, and the height of the plurality of fine second convex portions is 20 nm or more and 80 nm or less, and the plurality of fine parts are present.
  • the width of the second convex portion is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions is 20 nm or more and 80 nm or less.
  • the voids between the plurality of fine second convex portions are filled with an adhesive layer having a higher refractive index than air and a lower refractive index than the plurality of fine second convex portions, for example.
  • the relatively thin organic barrier layer 14B of the TFE structure 10B2 shown in FIG. 8B has a plurality of discretely distributed solid portions from the slope of the first inorganic barrier layer 12 on the side surface of the opening of the bank layer 48. It has a pixel peripheral solid portion 14Ba that extends to the periphery within the pixel Pix.
  • the surface 12S in contact with the organic barrier layer 14B of the first inorganic barrier layer 12 has a plurality of fine protrusions.
  • the first surface 14BS in contact with the second inorganic barrier layer 16 of the organic barrier layer 14B has a plurality of fine first convex portions, and the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the second surface 16S of the second inorganic barrier layer 16 has a plurality of fine second convex portions, and the height of the plurality of fine second convex portions is 20 nm or more and 80 nm or less, and the plurality of fine parts are present.
  • the width of the second convex portion is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions is 20 nm or more and 80 nm or less.
  • FIG. 9 is a schematic view showing the interface between the organic barrier layer 14A and the second inorganic barrier layer 16 (surface 14AS of the organic barrier layer 14A) and the surface 16S of the second inorganic barrier layer 16 in the TFE structure 10B (10B1, 10B2). It is a cross-sectional view.
  • the first surfaces 14AS and 14BS in contact with the second inorganic barrier layers 16 of the organic barrier layers 14A and 14B have a plurality of fine first convex portions and a plurality of fine first protrusions.
  • the height of the one convex portion is 20 nm or more and 80 nm or less
  • the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  • the second surface 16S of the second inorganic barrier layer 16 is affected by a plurality of fine first convex portions (surface roughness) of the first surfaces 14AS and 14BS of the organic barrier layers 14A and 14B, and a plurality of them. It has a fine second convex portion.
  • the height of the plurality of fine second convex portions is 20 nm or more and 80 nm or less, and the width of the plurality of fine second convex portions is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions is 20 nm or more and 80 nm or less.
  • the OLED display device of the second embodiment can further reduce the reflection in the TFE structure as compared with the OLED display device of the first embodiment.
  • O 2 , O 3 or N 2 O gas is turned into plasma to generate oxygen radicals in a high energy state, and the oxygen radicals are converted into the organic resin layer. Irradiate to.
  • the irradiated oxygen radicals combine with the carbon that constitutes the organic resin layer to generate CO 2 , and decompose and vaporize the organic resin layer (sometimes called ashing).
  • a concavo-convex structure having a height, a width, and an interval of 20 nm or more and 80 nm or less is independently formed on the surface of the organic barrier layer.
  • the organic resin film is formed on the flat portion of the element substrate when the solid portion 14Ba around the pixel is formed and then ashed, the third surface of the first inorganic barrier layer 12 existing on the flat portion is formed. It is not necessary to remove all the organic resin filling the fine concave portions (between the fine convex portions) of 12S, and the organic resin filling the fine concave portions may be left.
  • each barrier layer is flat, and the height and width of the convex portions formed on the surface are typically less than 20 nm. Is believed to have been less than 5 nm.
  • the embodiment of the present invention is suitably used for an OLED display device having a TFE structure, particularly a flexible OLED display device and a method for manufacturing the same.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Electroluminescent Light Sources (AREA)

Abstract

An organic EL display device (100) comprises: an element substrate (20) that includes a substrate (1) and a plurality of organic EL elements (3) supported by the substrate; and a thin film sealing structure (10) that covers the plurality of organic EL elements. The thin film sealing structure includes: a first inorganic barrier layer (12); an organic barrier layer (14) formed on the first inorganic barrier layer; and a second inorganic barrier layer (16) formed on the organic barrier layer. The first inorganic barrier layer includes: a first sub-barrier layer (12sa); and a second sub-barrier layer (12sb) that is formed on the first sub-barrier layer and that is in contact with the organic barrier layer. A surface (12S) of the first inorganic barrier layer contacting the organic barrier layer has a plurality of fine protrusions, each having a height of 20-80 nm and a width of 20-80 nm.

Description

有機EL表示装置Organic EL display device
 本発明は、有機EL表示装置に関する。 The present invention relates to an organic EL display device.
 有機EL(Electro Luminescence)表示装置が実用化され始めた。有機EL表示装置の特徴の1つにフレキシブルな表示装置が得られる点が挙げられる。有機EL表示装置は、画素ごとに少なくとも1つの有機EL素子(Organic Light Emitting Diode:OLED)と、各OLEDに供給される電流を制御する少なくとも1つのTFT(Thin Film Transistor)とを有する。以下、有機EL表示装置をOLED表示装置と呼ぶことにする。このようにOLEDごとにTFTなどのスイッチング素子を有するOLED表示装置は、アクティブマトリクス型OLED表示装置と呼ばれる。また、TFTおよびOLEDが形成された基板を素子基板ということにする。 Organic EL (Electro Luminescence) display devices have begun to be put into practical use. One of the features of the organic EL display device is that a flexible display device can be obtained. The organic EL display device has at least one organic EL element (Organic Light Emitting Diode: OLED) for each pixel, and at least one TFT (Thin Film Transistor) that controls the current supplied to each OLED. Hereinafter, the organic EL display device will be referred to as an OLED display device. Such an OLED display device having a switching element such as a TFT for each OLED is called an active matrix type OLED display device. Further, the substrate on which the TFT and the OLED are formed is referred to as an element substrate.
 OLED(特に有機発光層および陰極電極材料)は、水分の影響を受けて劣化しやすく、表示むらを生じやすい。OLEDを水分から保護するとともに、柔軟性を損なわない封止構造を提供する技術として、薄膜封止(Thin Film Encapsulation:TFE)技術が開発されている。薄膜封止技術は、無機バリア層と有機バリア層とを交互に積層することによって、薄膜で十分な水蒸気バリア性を得ようとするものである。OLED表示装置の耐湿信頼性の観点から、薄膜封止構造のWVTR(Water Vapor Transmission Rate)としては、典型的には1×10-4g/m2/day以下が求められている。 OLEDs (particularly organic light emitting layers and cathode electrode materials) are liable to deteriorate under the influence of moisture and are liable to cause display unevenness. Thin Film Encapsulation (TFE) technology has been developed as a technology for protecting the OLED from moisture and providing a sealing structure that does not impair flexibility. The thin film sealing technique attempts to obtain sufficient water vapor barrier properties in a thin film by alternately laminating inorganic barrier layers and organic barrier layers. From the viewpoint of moisture resistance and reliability of the OLED display device, the WVTR (Water Vapor Transmission Rate) of the thin film sealing structure is typically required to be 1 × 10 -4 g / m 2 / day or less.
 現在市販されているOLED表示装置に使われているTFE構造は、厚さが約5μm~約20μmの有機バリア層(高分子バリア層)を有している。このように比較的厚い有機バリア層は、素子基板の表面を平坦化する役割も担っている。比較的厚い有機バリア層は例えばインクジェット法を用いて形成される。 The TFE structure used in the OLED display devices currently on the market has an organic barrier layer (polymer barrier layer) having a thickness of about 5 μm to about 20 μm. Such a relatively thick organic barrier layer also plays a role of flattening the surface of the device substrate. A relatively thick organic barrier layer is formed, for example, by using an inkjet method.
 一方、最近、比較的薄い有機バリア層を有するTFE構造が検討されている。比較的薄い有機バリア層は、下層の無機バリア層(第1無機バリア層)の凸部(凸部を被覆した第1無機バリア層)の周囲にのみ離散的に有機樹脂膜(有機バリア層の「中実部」ということがある。)を有している。 On the other hand, recently, a TFE structure having a relatively thin organic barrier layer has been studied. The relatively thin organic barrier layer is discretely formed only around the convex portion (first inorganic barrier layer covering the convex portion) of the lower inorganic barrier layer (first inorganic barrier layer) of the organic resin film (organic barrier layer). It is sometimes called "solid part").
 例えば、特許文献1、2には以下の方法が記載されている。加熱気化させたミスト状の有機材料(例えばアクリルモノマー)を、室温以下の温度に維持された素子基板上に供給し、基板上で有機材料が凝縮し、滴状化する。滴状化した有機材料が、毛細管現象または表面張力によって、基板上を移動し、第1無機バリア層の凸部の側面と基板表面との境界部に偏在する。その後、有機材料を硬化させることによって、境界部に有機樹脂膜が形成される。また、特許文献3には、素子基板の平坦部上にも有機樹脂膜を形成した後、アッシングすることによって、離散的に分布した複数の中実部を有する有機バリア層を形成する方法が開示されている。参考のために、特許文献1~3の開示内容のすべてを本明細書に援用する。 For example, Patent Documents 1 and 2 describe the following methods. A mist-like organic material (for example, an acrylic monomer) that has been heated and vaporized is supplied onto an element substrate maintained at a temperature of room temperature or lower, and the organic material condenses and drops on the substrate. The droplet-like organic material moves on the substrate due to capillary action or surface tension, and is unevenly distributed at the boundary between the side surface of the convex portion of the first inorganic barrier layer and the surface of the substrate. Then, by curing the organic material, an organic resin film is formed at the boundary portion. Further, Patent Document 3 discloses a method of forming an organic resin film on a flat portion of an element substrate and then ashing to form an organic barrier layer having a plurality of discretely distributed solid portions. Has been done. For reference, all the disclosure contents of Patent Documents 1 to 3 are incorporated herein by reference.
国際公開第2014/196137号International Publication No. 2014/196137 特開2016-39120号公報Japanese Unexamined Patent Publication No. 2016-39120 国際公開第2018/003129号International Publication No. 2018/003129 特開2018-181807号公報Japanese Unexamined Patent Publication No. 2018-181807 特開2018-181808号公報Japanese Unexamined Patent Publication No. 2018-181808
 本発明者の検討によると、TFE構造を設けると、有機EL表示装置の光利用効率が低下するという問題がある。この原因の1つは、OLED(発光層)から出射された光の一部がTFE構造内の界面で反射されることにある。 According to the study of the present inventor, there is a problem that the light utilization efficiency of the organic EL display device is lowered when the TFE structure is provided. One of the causes is that a part of the light emitted from the OLED (light emitting layer) is reflected at the interface in the TFE structure.
 有機EL表示装置の光利用効率を向上させるために種々の技術が開発されている。例えば、特許文献4および5には、OLEDを形成する基板の表面に凹凸構造を形成し、この凹凸構造を利用して、OLEDの陽極(反射電極)の表面に規則的な凹凸を形成する方法が開示されている。特許文献4および5によると、規則的な凹凸を有する陽極での表面プラズモン共鳴を利用することによって、OLEDの光利用効率を向上させることができる。特許文献4には、凹凸構造が有する凸部の高さは10nm以上500nm以下、幅は50nm以上800nm以下、隣接する凸部間の間隔(ピッチ)は100nm以上1200nm以下と記載されており、特許文献5には、凹凸構造が有する凸部の高さは100nm以上800nm以下、幅は100nm以上250nm以下で、隣接する凸部間の間隔(ピッチ)は画素の色に応じて、520nm以上720nm以下(赤)、435nm以上635nm以下(緑)、370nm以上570nm以下(青)と記載されている。 Various technologies have been developed to improve the light utilization efficiency of organic EL display devices. For example, in Patent Documents 4 and 5, a method of forming a concavo-convex structure on the surface of a substrate on which an OLED is formed and using this concavo-convex structure to form regular irregularities on the surface of an anode (reflecting electrode) of the OLED. Is disclosed. According to Patent Documents 4 and 5, the light utilization efficiency of the OLED can be improved by utilizing the surface plasmon resonance at the anode having regular irregularities. Patent Document 4 describes that the height of the convex portion of the concave-convex structure is 10 nm or more and 500 nm or less, the width is 50 nm or more and 800 nm or less, and the interval (pitch) between adjacent convex portions is 100 nm or more and 1200 nm or less. According to Document 5, the height of the convex portion of the concave-convex structure is 100 nm or more and 800 nm or less, the width is 100 nm or more and 250 nm or less, and the interval (pitch) between adjacent convex portions is 520 nm or more and 720 nm or less depending on the color of the pixel. It is described as (red), 435 nm or more and 635 nm or less (green), and 370 nm or more and 570 nm or less (blue).
 しかしながら、特許文献4および5は、TFE構造による光利用効率の低下については言及すらされていない。 However, Patent Documents 4 and 5 do not even mention the decrease in light utilization efficiency due to the TFE structure.
 本発明は、上記の問題を解決するためになされたものであり、TFE構造における光の反射を抑制したOLED表示装置を提供することを目的とする。 The present invention has been made to solve the above problems, and an object of the present invention is to provide an OLED display device that suppresses light reflection in a TFE structure.
 本発明の実施形態によると、以下の項目に記載の解決手段が提供される。
[項目1]
 複数の画素を有する有機EL表示装置であって、
 基板および前記基板に支持された複数の有機EL素子を有する素子基板と、前記複数の有機EL素子を覆う薄膜封止構造とを有し、
 前記薄膜封止構造は、第1無機バリア層と、前記第1無機バリア層上に形成された有機バリア層と、前記有機バリア層上に形成された第2無機バリア層とを有し、
 前記第1無機バリア層は、第1サブバリア層と、前記第1サブバリア層上に形成され、前記有機バリア層に接する第2サブバリア層とを有し、
 前記第1無機バリア層の前記有機バリア層に接する表面は、複数の微細な凸部を有し、前記複数の微細な凸部の高さは20nm以上80nm以下であり、前記複数の微細な凸部の幅は20nm以上80nm以下である、有機EL表示装置。
[項目2]
 前記複数の微細な凸部の間隔は、20nm以上80nm以下である、項目1に記載の有機EL表示装置。
[項目3]
 前記有機バリア層を構成する樹脂材料は前記複数の微細な凸部の隙間に充填されている、項目1または2に記載の有機EL表示装置。
[項目4]
 前記第2サブバリア層は、離散的に分布した複数の島状部を有し、前記複数の島状部が前記複数の微細な凸部を形成している、項目1から3のいずれかに記載の有機EL表示装置。
[項目5]
 前記第2サブバリア層は、SiNまたはSiONで形成されている、項目1から4のいずれかに記載の有機EL表示装置。
[項目6]
 前記第1サブバリア層の表面粗さは、5nm未満である、項目1から5のいずれかに記載の有機EL表示装置。
[項目7]
 前記第1サブバリア層は、厚さが10nm以上30nm以下のAl23層である、項目1から6のいずれかに記載の有機EL表示装置。
[項目8]
 前記第1サブバリア層は、厚さが200nm以上400nm以下のSiN層またはSiON層である、項目1から6のいずれかに記載の有機EL表示装置。
[項目9]
 前記第2無機バリア層は、厚さが200nm以上400nm以下のSiN層またはSiON層を含む、項目1から8のいずれかに記載の有機EL表示装置。
[項目10]
 前記素子基板は、前記複数の画素のそれぞれを規定するバンク層をさらに有し、
 前記有機バリア層は、前記バンク層を覆い、平坦な表面を有している、項目1から9のいずれかに記載の有機EL表示装置。
[項目11]
 前記有機バリア層の厚さは3μm以上10μm以下である、項目10に記載の有機EL表示装置。
[項目12]
 前記素子基板は、前記複数の画素のそれぞれを規定するバンク層をさらに有し、
 前記バンク層は、前記複数の画素のそれぞれの周囲を包囲する斜面を有し、
 前記有機バリア層は、離散的に分布する複数の中実部を有し、
 前記複数の中実部は、前記第1無機バリア層の、前記斜面上の部分から前記画素内の周辺に至る画素周辺中実部を有する、項目1から9のいずれかに記載の有機EL表示装置。
[項目13]
 前記有機バリア層の厚さは50nm以上200nm未満である、項目12に記載の有機EL表示装置。
[項目14]
 前記有機バリア層の前記第2無機バリア層に接する第1表面は、複数の微細な第1凸部を有し、前記複数の微細な第1凸部の高さは20nm以上80nm以下であり、前記複数の微細な第1凸部の幅は20nm以上80nm以下である、項目1から13のいずれかに記載の有機EL表示装置。
[項目15]
 前記複数の微細な第1凸部の間隔は、20nm以上80nm以下である、項目14に記載の有機EL表示装置。
[項目16]
 前記第2無機バリア層が有する、前記第1表面と接する表面とは逆の第2表面は、複数の微細な第2凸部を有し、前記複数の微細な第2凸部の高さ、幅および間隔は、それぞれ独立に20nm以上80nm以下である、項目13に記載の有機EL表示装置。
According to embodiments of the present invention, the solutions described in the following items are provided.
[Item 1]
An organic EL display device having a plurality of pixels.
It has a substrate, an element substrate having a plurality of organic EL elements supported by the substrate, and a thin film sealing structure covering the plurality of organic EL elements.
The thin film sealing structure has a first inorganic barrier layer, an organic barrier layer formed on the first inorganic barrier layer, and a second inorganic barrier layer formed on the organic barrier layer.
The first inorganic barrier layer has a first sub-barrier layer and a second sub-barrier layer formed on the first sub-barrier layer and in contact with the organic barrier layer.
The surface of the first inorganic barrier layer in contact with the organic barrier layer has a plurality of fine convex portions, and the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and the plurality of fine convex portions. An organic EL display device having a width of 20 nm or more and 80 nm or less.
[Item 2]
The organic EL display device according to item 1, wherein the distance between the plurality of fine convex portions is 20 nm or more and 80 nm or less.
[Item 3]
The organic EL display device according to item 1 or 2, wherein the resin material constituting the organic barrier layer is filled in the gaps between the plurality of fine convex portions.
[Item 4]
The second sub-barrier layer has a plurality of discretely distributed island-shaped portions, and the plurality of island-shaped portions form the plurality of fine convex portions, according to any one of items 1 to 3. Organic EL display device.
[Item 5]
The organic EL display device according to any one of items 1 to 4, wherein the second sub-barrier layer is made of SiN or SiON.
[Item 6]
The organic EL display device according to any one of items 1 to 5, wherein the surface roughness of the first sub-barrier layer is less than 5 nm.
[Item 7]
The organic EL display device according to any one of items 1 to 6, wherein the first sub-barrier layer is an Al 2 O 3 layer having a thickness of 10 nm or more and 30 nm or less.
[Item 8]
The organic EL display device according to any one of items 1 to 6, wherein the first sub-barrier layer is a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
[Item 9]
The organic EL display device according to any one of items 1 to 8, wherein the second inorganic barrier layer includes a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
[Item 10]
The element substrate further has a bank layer that defines each of the plurality of pixels.
The organic EL display device according to any one of items 1 to 9, wherein the organic barrier layer covers the bank layer and has a flat surface.
[Item 11]
The organic EL display device according to item 10, wherein the thickness of the organic barrier layer is 3 μm or more and 10 μm or less.
[Item 12]
The element substrate further has a bank layer that defines each of the plurality of pixels.
The bank layer has a slope that surrounds each of the plurality of pixels.
The organic barrier layer has a plurality of discretely distributed solid parts.
The organic EL display according to any one of items 1 to 9, wherein the plurality of solid portions have a pixel peripheral solid portion extending from a portion on the slope to the periphery of the pixel of the first inorganic barrier layer. apparatus.
[Item 13]
The organic EL display device according to item 12, wherein the thickness of the organic barrier layer is 50 nm or more and less than 200 nm.
[Item 14]
The first surface of the organic barrier layer in contact with the second inorganic barrier layer has a plurality of fine first convex portions, and the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. The organic EL display device according to any one of items 1 to 13, wherein the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
[Item 15]
The organic EL display device according to item 14, wherein the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
[Item 16]
The second surface of the second inorganic barrier layer, which is opposite to the surface in contact with the first surface, has a plurality of fine second convex portions, and the height of the plurality of fine second convex portions. The organic EL display device according to item 13, wherein the width and the interval are independently 20 nm or more and 80 nm or less.
 本発明のある実施形態によると、TFE構造における光の反射を抑制したOLED表示装置が提供される。 According to an embodiment of the present invention, an OLED display device that suppresses light reflection in a TFE structure is provided.
本発明の実施形態によるOLED表示装置100のアクティブ領域の模式的な部分断面図である。It is a schematic partial sectional view of the active area of the OLED display device 100 by embodiment of this invention. 本発明の実施形態1によるOLED表示装置が有するTFE構造10Aの部分断面図である。FIG. 5 is a partial cross-sectional view of a TFE structure 10A included in the OLED display device according to the first embodiment of the present invention. 本発明の実施形態2によるOLED表示装置が有するTFE構造10Bの部分断面図である。It is a partial cross-sectional view of the TFE structure 10B included in the OLED display device according to Embodiment 2 of this invention. 本発明の実施形態によるOLED表示装置100の構造を模式的に示す平面図である。It is a top view which shows typically the structure of the OLED display device 100 by embodiment of this invention. TFE構造10A1を備える実施形態1のOLED表示装置100A1の模式的な断面図であり、図3中の4A-4A’線に沿った画素Pixを含む断面図である。It is a schematic cross-sectional view of the OLED display device 100A1 of Embodiment 1 provided with a TFE structure 10A1, and is the cross-sectional view including the pixel Pix along the line 4A-4A'in FIG. TFE構造10A1を備える実施形態1のOLED表示装置100A1の模式的な断面図であり、図3中の4A-4A’線に沿ったパーティクルPを含む断面図である。It is a schematic cross-sectional view of the OLED display device 100A1 of Embodiment 1 which comprises a TFE structure 10A1, and is the cross-sectional view which includes the particle P along the line 4A-4A'in FIG. TFE構造10A1を備える実施形態1のOLED表示装置100A1の模式的な断面図であり、図3中の4C-4C’線に沿った断面図である。It is a schematic cross-sectional view of the OLED display device 100A1 of Embodiment 1 provided with a TFE structure 10A1, and is the cross-sectional view along the line 4C-4C'in FIG. TFE構造10A2を備える実施形態1のOLED表示装置100A2の模式的な断面図であり、図3中の4A-4A’線に沿った画素Pixを含む断面図である。FIG. 5 is a schematic cross-sectional view of the OLED display device 100A2 of the first embodiment including the TFE structure 10A2, and is a cross-sectional view including a pixel Pix along the 4A-4A'line in FIG. TFE構造10Bを備える実施形態1のOLED表示装置100A2の模式的な断面図であり、図3中の4A-4A’線に沿ったパーティクルPを含む断面図である。It is a schematic cross-sectional view of the OLED display device 100A2 of Embodiment 1 provided with a TFE structure 10B, and is the cross-sectional view including the particle P along the line 4A-4A'in FIG. TFE構造10Bを備える実施形態1のOLED表示装置100A2の模式的な断面図であり、図3中の4C-4C’線に沿った断面図である。It is a schematic cross-sectional view of the OLED display device 100A2 of Embodiment 1 provided with a TFE structure 10B, and is the cross-sectional view along the line 4C-4C'in FIG. OLED表示装置100A1におけるTFE構造10A1の模式的な断面図である。It is a schematic cross-sectional view of the TFE structure 10A1 in the OLED display device 100A1. OLED表示装置100A2におけるTFE構造10A2の模式的な断面図である。It is a schematic cross-sectional view of the TFE structure 10A2 in the OLED display device 100A2. TFE構造10A(10A1、10A2)における第1無機バリア層12と有機バリア層14A、14Bとの界面の状態を示す模式的な断面図である。It is a schematic cross-sectional view which shows the state of the interface between the 1st inorganic barrier layer 12 and organic barrier layers 14A, 14B in a TFE structure 10A (10A1, 10A2). TFE構造10A(10A1、10A2)における第1無機バリア層12と第2無機バリア層16との界面(第1無機バリア層12の表面12S)および第2無機バリア層16の表面16Sの状態を示す模式的な断面図である。The state of the interface between the first inorganic barrier layer 12 and the second inorganic barrier layer 16 (surface 12S of the first inorganic barrier layer 12) and the surface 16S of the second inorganic barrier layer 16 in the TFE structure 10A (10A1, 10A2) is shown. It is a schematic cross-sectional view. OLED表示装置100B1におけるTFE構造10B1の模式的な断面図である。It is a schematic cross-sectional view of the TFE structure 10B1 in the OLED display device 100B1. OLED表示装置100B2におけるTFE構造10B2の模式的な断面図である。It is a schematic cross-sectional view of the TFE structure 10B2 in the OLED display device 100B2. TFE構造10B(10B1、10B2)における有機バリア層14A、14Bと第2無機バリア層16との界面および第2無機バリア層16の表面16Sを示す模式的な断面図である。FIG. 5 is a schematic cross-sectional view showing an interface between the organic barrier layers 14A and 14B and the second inorganic barrier layer 16 and the surface 16S of the second inorganic barrier layer 16 in the TFE structure 10B (10B1, 10B2).
 以下、図面を参照して、本発明の実施形態によるOLED表示装置およびその製造方法を説明する。なお、本発明の実施形態は、以下に例示する実施形態に限定されない。例えば、本発明の実施形態による有機EL表示装置は、フレキシブル基板に代えて、例えばガラス基板を有してもよい。 Hereinafter, the OLED display device according to the embodiment of the present invention and the manufacturing method thereof will be described with reference to the drawings. The embodiments of the present invention are not limited to the embodiments exemplified below. For example, the organic EL display device according to the embodiment of the present invention may have, for example, a glass substrate instead of the flexible substrate.
 まず、図1、図2Aおよび図2Bを参照して、本発明の実施形態によるOLED表示装置100の基本的な構成を説明する。図1は、本発明の実施形態によるOLED表示装置100のアクティブ領域の模式的な部分断面図であり、図2Aおよび図2Bは、OLED3上に形成されたTFE構造10の部分断面図である。図2Aは、実施形態1によるOLED表示装置が有するTFE構造10Aの部分断面図であり、図2Bは、実施形態2によるOLED表示装置が有するTFE構造10Bの部分断面図である。 First, the basic configuration of the OLED display device 100 according to the embodiment of the present invention will be described with reference to FIGS. 1, 2A and 2B. FIG. 1 is a schematic partial cross-sectional view of an active region of the OLED display device 100 according to the embodiment of the present invention, and FIGS. 2A and 2B are partial cross-sectional views of a TFE structure 10 formed on the OLED 3. FIG. 2A is a partial cross-sectional view of the TFE structure 10A included in the OLED display device according to the first embodiment, and FIG. 2B is a partial cross-sectional view of the TFE structure 10B included in the OLED display device according to the second embodiment.
 OLED表示装置100は、複数の画素を有し、画素ごとに少なくとも1つの有機EL素子(OLED)を有している。ここでは、簡単のために、1つのOLEDに対応する構造について説明する。 The OLED display device 100 has a plurality of pixels, and each pixel has at least one organic EL element (OLED). Here, for the sake of simplicity, a structure corresponding to one OLED will be described.
 図1に示すように、OLED表示装置100は、フレキシブル基板(以下、単に「基板」ということがある。)1と、基板1上に形成されたTFTを含む回路(バックプレーン)2と、回路2上に形成されたOLED3と、OLED3上に形成されたTFE構造10とを有している。OLED3は例えばトップエミッションタイプである。OLED3の最上部は、例えば、上部電極またはキャップ層(屈折率調整層)である。TFE構造10の上にはオプショナルな偏光板4が配置されている。 As shown in FIG. 1, the OLED display device 100 includes a flexible substrate (hereinafter, may be simply referred to as a “board”) 1, a circuit (backplane) 2 including a TFT formed on the substrate 1, and a circuit. It has an OLED 3 formed on the OLED 3 and a TFE structure 10 formed on the OLED 3. OLED3 is, for example, a top emission type. The uppermost portion of the OLED 3 is, for example, an upper electrode or a cap layer (refractive index adjusting layer). An optional polarizing plate 4 is arranged on the TFE structure 10.
 基板1は、例えば厚さが15μmのポリイミドフィルムである。TFTを含む回路2の厚さは例えば4μmであり、OLED3の厚さは例えば1μmであり、TFE構造10の厚さは例えば1.5μm以下である。 The substrate 1 is, for example, a polyimide film having a thickness of 15 μm. The thickness of the circuit 2 including the TFT is, for example, 4 μm, the thickness of the OLED 3 is, for example, 1 μm, and the thickness of the TFE structure 10 is, for example, 1.5 μm or less.
 図2Aは、実施形態1によるOLED表示装置が有するTFE構造10Aの部分断面図である。TFE構造10Aは、第1無機バリア層(例えばSiN層)12と、第1無機バリア層12上に形成された有機バリア層(例えばアクリル樹脂層)14と、有機バリア層14上に形成された第2無機バリア層(例えばSiN層)16とを有する。第1無機バリア層12は、OLED3の直上に形成されている。有機バリア層14は、比較的厚く、平坦化層を兼ねてもよいし(図4A参照)、比較的薄く、離散的に分布する複数の中実部を有してもよい(図5A参照)。有機バリア層14は、無色透明の光硬化性樹脂(例えば、アクリル樹脂またはエポキシ樹脂)で形成されることが好ましく、例えば、厚さが1μmのときの可視光の透過率は95%以上であることが好ましい。光硬化性樹脂の屈折率は、例えば、約1.48~約1.61である。 FIG. 2A is a partial cross-sectional view of the TFE structure 10A included in the OLED display device according to the first embodiment. The TFE structure 10A was formed on the first inorganic barrier layer (for example, SiN layer) 12, the organic barrier layer (for example, acrylic resin layer) 14 formed on the first inorganic barrier layer 12, and the organic barrier layer 14. It has a second inorganic barrier layer (for example, SiN layer) 16. The first inorganic barrier layer 12 is formed directly above the OLED 3. The organic barrier layer 14 may be relatively thick and also serve as a flattening layer (see FIG. 4A), or may have a plurality of relatively thin and discretely distributed solid parts (see FIG. 5A). .. The organic barrier layer 14 is preferably formed of a colorless and transparent photocurable resin (for example, acrylic resin or epoxy resin), and for example, when the thickness is 1 μm, the transmittance of visible light is 95% or more. Is preferable. The refractive index of the photocurable resin is, for example, about 1.48 to about 1.61.
 OLED3から出射された光の内でTFE構造10Aを通過した光(の一部)が、OLED表示装置100から出射され、表示に用いられる。しかしながら、TFE構造10A内に入射した光の一部は、第1無機バリア層12と有機バリア層14との界面で反射される。例えば、SiN層の屈折率は、1.85であり、アクリル樹脂層の屈折率は、1.54であり、屈折率差(Δn)が0.31以上と大きい。したがって、第1無機バリア層12と有機バリア層14との界面において、OLED3から出射された光が反射され、ロスとなる。 Of the light emitted from the OLED 3, (a part of) the light that has passed through the TFE structure 10A is emitted from the OLED display device 100 and used for display. However, a part of the light incident on the TFE structure 10A is reflected at the interface between the first inorganic barrier layer 12 and the organic barrier layer 14. For example, the refractive index of the SiN layer is 1.85, the refractive index of the acrylic resin layer is 1.54, and the refractive index difference (Δn) is as large as 0.31 or more. Therefore, the light emitted from the OLED 3 is reflected at the interface between the first inorganic barrier layer 12 and the organic barrier layer 14, resulting in loss.
 本発明の実施形態1によるOLED表示装置が有するTFE構造10Aの第1無機バリア層12は、第1サブバリア層12saと、第1サブバリア層12sa上に形成され、有機バリア層14に接する第2サブバリア層12sbとを有しており、第1無機バリア層12の有機バリア層14に接する表面12Sは、複数の微細な凸部を有し、複数の微細な凸部の高さは20nm以上80nm以下であり、複数の微細な凸部の幅は20nm以上80nm以下である(図7A参照)。第1無機バリア層12の有機バリア層14に接する表面12Sが、この様な微細な凸部を有すると、以下で説明するように、屈折率に起因する反射が低減・解消される。その結果、本発明の実施形態によるOLED表示装置は、従来よりも高い光の利用効率を実現することができる。 The first inorganic barrier layer 12 of the TFE structure 10A included in the OLED display device according to the first embodiment of the present invention is formed on the first sub-barrier layer 12sa and the first sub-barrier layer 12sa, and is in contact with the organic barrier layer 14. The surface 12S having the layer 12sb and in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine protrusions, and the height of the plurality of fine protrusions is 20 nm or more and 80 nm or less. The width of the plurality of fine convex portions is 20 nm or more and 80 nm or less (see FIG. 7A). When the surface 12S of the first inorganic barrier layer 12 in contact with the organic barrier layer 14 has such a fine convex portion, reflection due to the refractive index is reduced or eliminated as described below. As a result, the OLED display device according to the embodiment of the present invention can realize higher light utilization efficiency than before.
 一般に、可視光の波長よりも微細な構造体(凸部)を物体の表面に形成し、その微細構造体の間に空気が充填されていれば、空気を含む微細構造が形成されている領域(レイヤー)の平均屈折率(実効的な屈折率)は微細構造を構成する物質自体の屈折率よりも小さくなる。さらに、微細構造の水平方向の断面積を微細構造の高さ方向に対して徐々に大きくしていくことで、平均屈折率を空気から微細構造の底部にかけて緩やかに変化させれば、空気と物体との界面における急激な屈折率変化が無くなり、光の反射を低減できることが知られている。 Generally, if a structure (convex portion) finer than the wavelength of visible light is formed on the surface of an object and air is filled between the fine structures, a region in which a fine structure containing air is formed. The average refractive index (effective refractive index) of (layer) is smaller than the refractive index of the substance itself constituting the fine structure. Furthermore, if the horizontal cross-sectional area of the microstructure is gradually increased with respect to the height direction of the microstructure so that the average refractive index is gradually changed from the air to the bottom of the microstructure, air and an object can be obtained. It is known that the sudden change in the refractive index at the interface with the light can be eliminated and the reflection of light can be reduced.
 本発明の実施形態1においては、上述した物体が第1サブバリア層12saに該当し、第1サブバリア層12saの表面粗さは5nm未満である。この第1サブバリア層12saの直上に、微細構造体として、高さが20nm以上80nm以下、幅が20nm以上80nm以下で離散的に存在する凸部(第2サブバリア層12sb)が形成されている。なお、平均屈折率の変化をできるだけ緩やかにするためには、第2サブバリア層12sbの高さの下限は、40nm以上がさらに好ましい。高さが高いほど、屈折率変化を緩やかにすることができるためである。ただし、高さが可視光の下限である400nmに近付くと、第2サブバリア層12sbの側面での反射が無視できなくなるので、第2サブバリア層12sbの高さの上限は可視光の下限波長よりも十分に小さい80nm以下が好ましい。第2サブバリア層12sbを構成する物質はSiNやSiONが好ましく、成膜方法にも依存するがこれらの屈折率は1.7~2.1程度である。例えば100℃以下の基板温度でPECVD(Plasma Enhanced Chemical Vapor Deposition)法を用いてSiN層を形成した時の屈折率はおよそ1.85である。第1サブバリア層12saを構成する材料は、第2サブバリア層12sbと同じでもよく、異なっていてもよい。第1サブバリア層12saの厚さは有機EL素子に対する耐湿信頼性を確保するために、SiN膜やSiON膜を用いた場合は少なくとも200nm以上であることが好ましい。ただし、第1サブバリア層12saとしてAl23膜を、緻密な薄膜形成が可能なALD(Atomic Layer Deposition)法を用いて形成する場合は、厚さは10nm以上30nm以下であってもよい。 In the first embodiment of the present invention, the above-mentioned object corresponds to the first sub-barrier layer 12sa, and the surface roughness of the first sub-barrier layer 12sa is less than 5 nm. Immediately above the first sub-barrier layer 12sa, convex portions (second sub-barrier layer 12sb) having a height of 20 nm or more and 80 nm or less and a width of 20 nm or more and 80 nm or less are formed discretely as a microstructure. In order to make the change in the average refractive index as gentle as possible, the lower limit of the height of the second sub-barrier layer 12sb is more preferably 40 nm or more. This is because the higher the height, the slower the change in the refractive index. However, when the height approaches 400 nm, which is the lower limit of visible light, reflection on the side surface of the second sub-barrier layer 12sb cannot be ignored. Therefore, the upper limit of the height of the second sub-barrier layer 12sb is higher than the lower limit wavelength of visible light. It is preferably 80 nm or less, which is sufficiently small. The substance constituting the second sub-barrier layer 12sb is preferably SiN or SiON, and these refractive indexes are about 1.7 to 2.1, although it depends on the film forming method. For example, the refractive index when the SiN layer is formed by the PECVD (Plasma Enhanced Chemical Vapor Deposition) method at a substrate temperature of 100 ° C. or lower is about 1.85. The material constituting the first sub-barrier layer 12sa may be the same as or different from that of the second sub-barrier layer 12sb. The thickness of the first sub-barrier layer 12sa is preferably at least 200 nm or more when a SiN film or a SiON film is used in order to ensure moisture resistance reliability for the organic EL element. However, when the Al 2 O 3 film is formed as the first sub-barrier layer 12sa by using the ALD (Atomic Layer Deposition) method capable of forming a dense thin film, the thickness may be 10 nm or more and 30 nm or less.
 本実施形態においては、複数の微細な凸部の間に空気が充填されているのではなく、有機バリア層を構成する樹脂材料(典型的な屈折率は1.5程度)が充填されていることが好ましい。複数の微細な凸部の間に空気が充填されていたり、少なくとも、有機バリア層と複数の微細な凸部との間に空気が存在すると、空気と凸部を構成する材料との間の屈折率差が大きすぎるために、凸部の高さを20nm以上80nm以下としても、反射を十分に抑制できないことがある。 In the present embodiment, air is not filled between the plurality of fine protrusions, but a resin material (typically having a refractive index of about 1.5) constituting the organic barrier layer is filled. Is preferable. Refraction between the air and the materials that make up the protrusions when air is filled between the plurality of fine protrusions, or at least when air is present between the organic barrier layer and the plurality of fine protrusions. Since the rate difference is too large, even if the height of the convex portion is set to 20 nm or more and 80 nm or less, reflection may not be sufficiently suppressed.
 なお、第2サブバリア層12sbの各凸部の断面形状(高さ方向を含む面(すなわち基板に垂直な面)における断面形状)を放物線形状とすると、凸部の高さ方向に直交する面(すなわち基板面に平行な面)における凸部の断面積(断面形状はほぼ円形)が高さ方向に沿って直線的に変化するので、結果的に、平均屈折率を高さ方向に沿って最も緩やかに変化させることができる。したがって、ある特定の高さの凸部を形成する際、その断面形状(高さ方向を含む面)を放物線形状とすることによって、反射率を最も効果的に低減できる。 If the cross-sectional shape of each convex portion of the second sub-barrier layer 12sb (the cross-sectional shape on the surface including the height direction (that is, the surface perpendicular to the substrate)) is a parabolic shape, the surface (that is, the surface orthogonal to the height direction of the convex portion). That is, the cross-sectional area (the cross-sectional shape is almost circular) of the convex portion on the surface parallel to the substrate surface changes linearly along the height direction, and as a result, the average refractive index is the highest along the height direction. It can be changed slowly. Therefore, when forming a convex portion having a specific height, the reflectance can be most effectively reduced by making the cross-sectional shape (the surface including the height direction) a parabolic shape.
 平均屈折率が緩やかに変化していれば、複数の微細な凸部が周期的に規則正しく形成されていなくても、反射率を低減させることができる。したがって、複数の微細な凸部は必ずしも周期構造でなくてもよい。しかし、複数の微細な凸部のうちの少なくとも一部であっても、光の波長と同程度以上の幅を有している部分が存在すると、その部分で光の反射(散乱)が起こり、OLED表示装置において表示むらとして視認されてしまうので、好ましくない。そのため、複数の微細な凸部はそれぞれが異なる高さ、幅を有していてもよいが、それらの全てが20nm以上80nm以下の範囲に含まれていることが好ましい。 If the average refractive index changes gently, the reflectance can be reduced even if a plurality of fine protrusions are not periodically and regularly formed. Therefore, the plurality of fine protrusions do not necessarily have to have a periodic structure. However, if there is a portion having a width equal to or more than the wavelength of light even in at least a part of the plurality of fine convex portions, light reflection (scattering) occurs in that portion. It is not preferable because it is visually recognized as uneven display on the OLED display device. Therefore, the plurality of fine convex portions may have different heights and widths, but it is preferable that all of them are included in the range of 20 nm or more and 80 nm or less.
 なお、本発明者は、さらに効果的に反射を抑制するためには、複数の微細な凸部の高さ、幅だけでなく、複数の微細な凸部間の間隔(隣接する微細な凸部間の間隔)も、可視光(400nm以上700nm以下)の波長に対して十分に小さくすることが有効であることを見出した。すわなち、複数の微細な凸部間の間隔も20nm以上80nm以下とすることが好ましい。複数の微細な凸部(第2サブバリア層12sb)間の間隔、言い換えると、第1サブバリア層12saの表面が露出している平坦な部分の幅が可視光の波長の下限400nmの5分の1の80nmを超えると、その平坦部で無視できない反射が起きてしまうことがある。 In order to suppress reflection more effectively, the present inventor has not only the height and width of the plurality of fine protrusions, but also the distance between the plurality of fine protrusions (adjacent fine protrusions). It was found that it is effective to make the interval between them sufficiently small with respect to the wavelength of visible light (400 nm or more and 700 nm or less). That is, it is preferable that the distance between the plurality of fine protrusions is also 20 nm or more and 80 nm or less. The spacing between the plurality of fine protrusions (second sub-barrier layer 12sb), in other words, the width of the flat portion where the surface of the first sub-barrier layer 12sa is exposed is one-fifth of the lower limit of the wavelength of visible light of 400 nm. If it exceeds 80 nm, non-negligible reflection may occur in the flat portion.
 したがって、本発明の実施形態1においては、複数の微細な凸部のそれぞれの高さ、幅、および隣接する微細な凸部間の間隔は、それぞれ独立に、20nm以上80nm以下の範囲にあることが好ましい。このことによって、第1無機バリア層の表面(第2サブバリア層12sbの頂部および側面、さらには第1サブバリア層12saの表面が露出している平坦面)での反射を効果的に抑制することができる。 Therefore, in the first embodiment of the present invention, the height and width of each of the plurality of fine protrusions and the distance between the adjacent fine protrusions are independently in the range of 20 nm or more and 80 nm or less. Is preferable. As a result, reflection on the surface of the first inorganic barrier layer (the top and side surfaces of the second sub-barrier layer 12sb, and the flat surface where the surface of the first sub-barrier layer 12sa is exposed) can be effectively suppressed. it can.
 なお、屈折率が異なる層の界面における反射を防止する他の方法として、高屈折率の誘電体層と低屈折率の誘電体層とを交互に積層した誘電体多層構造体を用いる方法も知られている。しかし、この誘電体多層構造は、干渉を利用するので、界面に対してある特定の角度(設計で決められる)で入射する光(典型的には垂直入射光)の反射を効果的に低減することができるが、それ以外の角度で入射する光の反射を低減する効果は限定的である。また、同様の理由から、特定の波長(設計で決められる)の光の反射を効果的に低減することができるが、それ以外の波長の光の反射を低減する効果は限定的である。これに対して、本実施形態1によれば、幅広い入射角の光に対して、および、広い波長範囲の光に対して、高い反射防止効果を得ることができる。 As another method for preventing reflection at the interface between layers having different refractive indexes, a method using a dielectric multilayer structure in which dielectric layers having a high refractive index and dielectric layers having a low refractive index are alternately laminated is also known. Has been done. However, since this dielectric multilayer structure utilizes interference, it effectively reduces the reflection of light (typically vertically incident light) that is incident on the interface at a particular angle (determined by design). However, the effect of reducing the reflection of light incident at other angles is limited. Further, for the same reason, the reflection of light of a specific wavelength (determined by design) can be effectively reduced, but the effect of reducing the reflection of light of other wavelengths is limited. On the other hand, according to the first embodiment, a high antireflection effect can be obtained for light having a wide incident angle and for light having a wide wavelength range.
 なお、複数の微細な凸部の幅が20nmよりも小さいと、アスペクト比(高さ/幅)が大きい、細長い形状の凸部を形成することになるので、製造上の困難性が増す。特に、このような細長い形状の凸部をPECVD法で形成するのは困難である。したがって、複数の微細な凸部の幅は20nm以上が好ましい。 If the width of the plurality of fine convex portions is smaller than 20 nm, an elongated convex portion having a large aspect ratio (height / width) will be formed, which increases manufacturing difficulty. In particular, it is difficult to form such an elongated convex portion by the PECVD method. Therefore, the width of the plurality of fine protrusions is preferably 20 nm or more.
 複数の微細な凸部(第2サブバリア層12sb)を形成するPECVD法以外の方法としては、ゾルゲル法によって多孔質を有する低屈折率膜を形成する方法や、金型を用いた成形法によって微小突起列を形成する方法、レーザ光照射等によって微細構造をパターニングにより形成する方法などがある。この中でも、PECVD法は、後述するように、第1サブバリア層12saと第2サブバリア層12sbとを連続して形成することができるので、量産性の観点から好ましい。 As a method other than the PECVD method for forming a plurality of fine convex portions (second sub-barrier layer 12sb), a method for forming a porous low refractive index film by a sol-gel method or a molding method using a mold is used for minute particles. There are a method of forming a row of protrusions, a method of forming a fine structure by patterning by irradiation with a laser beam, and the like. Among these, the PECVD method is preferable from the viewpoint of mass productivity because the first sub-barrier layer 12sa and the second sub-barrier layer 12sb can be continuously formed as described later.
 TFE構造10A内に入射した光の一部は、有機バリア層14と第2無機バリア層16との界面でも反射される。また、第2無機バリア層16の上には、例えば、接着層(粘着層を含む)を介して、偏光板などの光学フィルム、あるいは、タッチパネル層が配置されることがある。接着層は、屈折率が1.5程度の高分子材料で形成されているので、第2無機バリア層16と接着層との界面においても、これらの層の屈折率差に起因して、OLED3から出射された光の一部が反射される。また、第2無機バリア層16を、空気層を間に介して覆うように保護ガラス等を配置する場合でも、第2無機バリア層の表面(空気層との界面)においてOLED3から出射された光の一部が反射される。 A part of the light incident on the TFE structure 10A is also reflected at the interface between the organic barrier layer 14 and the second inorganic barrier layer 16. Further, on the second inorganic barrier layer 16, for example, an optical film such as a polarizing plate or a touch panel layer may be arranged via an adhesive layer (including an adhesive layer). Since the adhesive layer is made of a polymer material having a refractive index of about 1.5, even at the interface between the second inorganic barrier layer 16 and the adhesive layer, due to the difference in refractive index between these layers, OLED3 Part of the light emitted from is reflected. Further, even when the protective glass or the like is arranged so as to cover the second inorganic barrier layer 16 with the air layer interposed therebetween, the light emitted from the OLED 3 on the surface of the second inorganic barrier layer (the interface with the air layer). Part of is reflected.
 図2Bに示す本発明の実施形態2によるOLED表示装置が有するTFE構造10Bは、有機バリア層14の第2無機バリア層16に接する第1表面14Sが複数の微細な第1凸部を有し、複数の微細な第1凸部の高さは20nm以上80nm以下であり、複数の微細な第1凸部の幅は20nm以上80nm以下である(図9参照)。また、複数の微細な第1凸部間の間隔も20nm以上80nm以下であることが好ましい。有機バリア層14の第2無機バリア層16に接する第1表面14Sがこの様な微細な凸部を有すると、屈折率に起因する反射が低減・解消される。その結果、本発明の実施形態2によるOLED表示装置は、実施形態1のOLED表示装置よりもさらに高い光の利用効率を実現することができる。 In the TFE structure 10B included in the OLED display device according to the second embodiment of the present invention shown in FIG. 2B, the first surface 14S in contact with the second inorganic barrier layer 16 of the organic barrier layer 14 has a plurality of fine first convex portions. The height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less, and the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less (see FIG. 9). Further, the interval between the plurality of fine first convex portions is also preferably 20 nm or more and 80 nm or less. When the first surface 14S in contact with the second inorganic barrier layer 16 of the organic barrier layer 14 has such a fine convex portion, reflection due to the refractive index is reduced or eliminated. As a result, the OLED display device according to the second embodiment of the present invention can realize a higher light utilization efficiency than the OLED display device according to the first embodiment.
 第2無機バリア層16の第2表面は、有機バリア層14の第1表面14Sの複数の微細な第1凸部(表面粗さ)の影響を受け、複数の微細な第2凸部を有し得る。ただし、有機バリア層14の第1表面14Sの複数の微細な第1凸部の高さが小さい場合には、第2無機バリア層16の第2表面16Sの複数の微細な第2凸部の高さは20nm未満になることがある。 The second surface of the second inorganic barrier layer 16 is affected by a plurality of fine first convex portions (surface roughness) of the first surface 14S of the organic barrier layer 14, and has a plurality of fine second convex portions. Can be done. However, when the height of the plurality of fine first convex portions of the first surface 14S of the organic barrier layer 14 is small, the height of the plurality of fine second convex portions of the second surface 16S of the second inorganic barrier layer 16 is small. The height can be less than 20 nm.
 なお、実施形態1で説明した第1無機バリア層と同様に、第2無機バリア層16の第2表面に対して、凸部を構成するサブバリア層を形成してもよい。 Similar to the first inorganic barrier layer described in the first embodiment, a sub-barrier layer forming a convex portion may be formed on the second surface of the second inorganic barrier layer 16.
 図7Bを参照して後述するように、実施形態2においては、第2無機バリア層16が有する第2表面16Sが複数の微細な第2凸部を有し、複数の微細な第2凸部の高さは20nm以上80nm以下であり、複数の微細な第2凸部の幅は20nm以上80nm以下であり得る。さらに、複数の微細な第2凸部間の間隔は20nm以上80nm以下であり得る。第2無機バリア層16の第2表面16Sがこのような複数の微細な第2凸部を有することによって、第2無機バリア層16の第2表面16Sにおける反射も低減される。 As will be described later with reference to FIG. 7B, in the second embodiment, the second surface 16S of the second inorganic barrier layer 16 has a plurality of fine second convex portions, and the plurality of fine second convex portions. The height of the second convex portion may be 20 nm or more and 80 nm or less, and the width of the plurality of fine second convex portions may be 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions can be 20 nm or more and 80 nm or less. Since the second surface 16S of the second inorganic barrier layer 16 has such a plurality of fine second convex portions, reflection on the second surface 16S of the second inorganic barrier layer 16 is also reduced.
 なお、第2無機バリア層16が有する第2表面16Sが複数の微細な第2凸部を有し、その上に接着層を介してタッチパネル層やカバーフィルムが形成されている場合、接着層は複数の微細な第2凸部間の空隙に充填されていることが好ましい。このような構成とすることにより、第2無機バリア層16と接着層との間での平均屈折率の変化を、空気が充填されている場合よりも緩やかにすることができるので、第2表面16Sでの反射をより効果的に低減することができる。 When the second surface 16S of the second inorganic barrier layer 16 has a plurality of fine second convex portions and a touch panel layer or a cover film is formed on the second surface 16S via an adhesive layer, the adhesive layer is formed. It is preferable that the gap between the plurality of fine second convex portions is filled. With such a configuration, the change in the average refractive index between the second inorganic barrier layer 16 and the adhesive layer can be made slower than when air is filled, so that the second surface can be made gentler. The reflection at 16S can be reduced more effectively.
 なお、実施形態1によるOLED表示装置における第1無機バリア層12の有機バリア層14に接する表面12Sが有する複数の微細な凸部を設けなくても、有機バリア層14の第2無機バリア層16に接する第1表面14Sが上述の微細な凸部を有せば、少なくとも有機バリア層14と第2無機バリア層16との界面における反射が低減されるので、従来よりも高い光の利用効率を実現することができる。 The second inorganic barrier layer 16 of the organic barrier layer 14 does not have to be provided with a plurality of fine protrusions of the surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 in the OLED display device according to the first embodiment. If the first surface 14S in contact with the surface has the above-mentioned fine protrusions, at least the reflection at the interface between the organic barrier layer 14 and the second inorganic barrier layer 16 is reduced, so that the light utilization efficiency is higher than before. It can be realized.
 図3に本発明の実施形態によるOLED表示装置100の模式的な平面図を示す。実施形態1および実施形態2のOLED表示装置は、いずれもOLED表示装置100と同じ平面構造を有し得る。 FIG. 3 shows a schematic plan view of the OLED display device 100 according to the embodiment of the present invention. Both the OLED display devices of the first embodiment and the second embodiment may have the same planar structure as the OLED display device 100.
 OLED表示装置100は、フレキシブル基板1と、フレキシブル基板1上に形成された回路(バックプレーン)2と、回路2上に形成された複数のOLED3と、OLED3上に形成されたTFE構造10とを有している。複数のOLED3が配列されている層をOLED層3ということがある。なお、回路2とOLED層3とが一部の構成要素を共有してもよい。TFE構造10の上にはオプショナルな偏光板(図1中の参照符号4を参照)がさらに配置されてもよい。また、例えば、TFE構造10と偏光板との間にタッチパネル機能を担う層が配置されてもよい。すなわち、OLED表示装置100は、オンセル型のタッチパネル付き表示装置に改変され得る。 The OLED display device 100 comprises a flexible substrate 1, a circuit (backplane) 2 formed on the flexible substrate 1, a plurality of OLEDs 3 formed on the circuit 2, and a TFE structure 10 formed on the OLED 3. Have. The layer in which a plurality of OLEDs 3 are arranged may be referred to as an OLED layer 3. The circuit 2 and the OLED layer 3 may share some components. An optional polarizing plate (see reference numeral 4 in FIG. 1) may be further arranged on the TFE structure 10. Further, for example, a layer having a touch panel function may be arranged between the TFE structure 10 and the polarizing plate. That is, the OLED display device 100 can be modified into an on-cell type display device with a touch panel.
 回路2は、複数のTFT(不図示)と、それぞれが複数のTFT(不図示)のいずれかに接続された複数のゲートバスライン(不図示)および複数のソースバスライン(不図示)とを有している。回路2は、複数のOLED3を駆動するための公知の回路であってよい。複数のOLED3は、回路2が有する複数のTFTのいずれかに接続されている。OLED3も公知のOLEDであってよい。 The circuit 2 has a plurality of TFTs (not shown), and a plurality of gate bus lines (not shown) and a plurality of source bus lines (not shown), each of which is connected to any of the plurality of TFTs (not shown). Have. The circuit 2 may be a known circuit for driving a plurality of OLEDs 3. The plurality of OLEDs 3 are connected to any of the plurality of TFTs included in the circuit 2. The OLED 3 may also be a known OLED.
 OLED表示装置100は、さらに、複数のOLED3が配置されているアクティブ領域(図3中の破線で囲まれた領域)R1の外側の周辺領域R2に配置された複数の端子38と、複数の端子38と複数のゲートバスラインまたは複数のソースバスラインのいずれかとを接続する複数の引出し配線30を有しており、TFE構造10は、複数のOLED3の上および複数の引出し配線30のアクティブ領域R1側の部分の上に形成されている。すなわち、TFE構造10はアクティブ領域R1の全体を覆い、かつ、複数の引出し配線30のアクティブ領域R1側の部分の上に選択的に形成されており、引出し配線30の端子38側および端子38は、TFE構造10では覆われていない。 The OLED display device 100 further includes a plurality of terminals 38 arranged in a peripheral region R2 outside the active region (area surrounded by a broken line in FIG. 3) R1 in which the plurality of OLEDs 3 are arranged, and a plurality of terminals. The TFE structure 10 has a plurality of leader wires 30 connecting the 38 with any of the plurality of gate bus lines or the plurality of source bus lines, and the TFE structure 10 is on the plurality of OLEDs 3 and the active region R1 of the plurality of leader wires 30. It is formed on the side part. That is, the TFE structure 10 covers the entire active region R1 and is selectively formed on the portion of the plurality of drawer wirings 30 on the active region R1 side, and the terminal 38 side and the terminal 38 of the drawer wiring 30 are formed. , Not covered by TFE structure 10.
 以下では、引出し配線30と端子38とが同じ導電層を用いて一体に形成された例を説明するが、互いに異なる導電層(積層構造を含む)を用いて形成されてもよい。 In the following, an example in which the drawer wiring 30 and the terminal 38 are integrally formed by using the same conductive layer will be described, but they may be formed by using different conductive layers (including a laminated structure).
 次に、図4A、図4Bおよび図4Cを参照して、比較的厚い有機バリア層14Aを有するTFE構造10A1を備える、実施形態1によるOLED表示装置100A1の構造を説明する。図4Aは図3中の4A-4A’線に沿った画素Pixを含む断面図であり、図4Bは図3中の4A-4A’線に沿ったパーティクルPを含む断面図であり、図4Cは図3中の4C-4C’線に沿った断面図である。 Next, with reference to FIGS. 4A, 4B, and 4C, the structure of the OLED display device 100A1 according to the first embodiment, which includes the TFE structure 10A1 having a relatively thick organic barrier layer 14A, will be described. 4A is a cross-sectional view including the pixel Pix along the 4A-4A'line in FIG. 3, and FIG. 4B is a cross-sectional view including the particles P along the 4A-4A' line in FIG. 3C. Is a cross-sectional view taken along the line 4C-4C'in FIG.
 図4Aに示す様に、薄膜封止構造10A1は、第1無機バリア層12と、第1無機バリア層12上に形成された有機バリア層14Aと、有機バリア層14A上に形成された第2無機バリア層16とを有している。有機バリア層14Aは、比較的厚く、平坦な表面を有している。 As shown in FIG. 4A, the thin film sealing structure 10A1 has a first inorganic barrier layer 12, an organic barrier layer 14A formed on the first inorganic barrier layer 12, and a second formed on the organic barrier layer 14A. It has an inorganic barrier layer 16. The organic barrier layer 14A has a relatively thick and flat surface.
 OLED表示装置100A1の素子基板20は、複数の画素Pixのそれぞれを規定するバンク層48をさらに有している。バンク層48は、絶縁材料から形成されており、OLED3の下部電極42と有機層(有機EL層)44との間に形成されている。OLED3は、下部電極42と、下部電極42上に形成された有機層44と、有機層44上に形成された上部電極46とを含み、下部電極42および上部電極46は、例えば、それぞれ、陽極および陰極を構成する。上部電極46は、アクティブ領域の画素全体にわたって形成されている共通の電極であり、下部電極(画素電極)42は画素ごとに形成されている。下部電極42と有機層44との間にバンク層48が存在すると、下部電極42から有機層44に正孔が注入されない。従って、バンク層48が存在する領域は画素Pixとして機能しないので、バンク層48が画素Pixの外縁を規定する。バンク層48は、PDL(Pixel Defining Layer)と呼ばれることもある。 The element substrate 20 of the OLED display device 100A1 further has a bank layer 48 that defines each of the plurality of pixels Pix. The bank layer 48 is formed of an insulating material, and is formed between the lower electrode 42 of the OLED 3 and the organic layer (organic EL layer) 44. The OLED 3 includes a lower electrode 42, an organic layer 44 formed on the lower electrode 42, and an upper electrode 46 formed on the organic layer 44, and the lower electrode 42 and the upper electrode 46 are, for example, anodes, respectively. And constitutes the cathode. The upper electrode 46 is a common electrode formed over the entire pixel in the active region, and the lower electrode (pixel electrode) 42 is formed for each pixel. If the bank layer 48 is present between the lower electrode 42 and the organic layer 44, holes are not injected from the lower electrode 42 into the organic layer 44. Therefore, since the region where the bank layer 48 exists does not function as the pixel Pix, the bank layer 48 defines the outer edge of the pixel Pix. The bank layer 48 is sometimes called a PDL (Pixel Defining Layer).
 バンク層48は、画素Pixに対応する開口部を有し、開口部の側面は、順テーパー側面部分TSFを有する斜面を有する。バンク層48の斜面は、各画素の周囲を包囲している。バンク層48は、例えば感光性樹脂(例えばポリイミドまたはアクリル樹脂)を用いて形成される。バンク層48の厚さは、例えば1μm以上2μm以下である。バンク層48の斜面の傾斜角θbは、60°以下である。バンク層48の斜面の傾斜角θbが60°超であると、バンク層48の上に位置する層に欠陥が生じることがある。 The bank layer 48 has an opening corresponding to the pixel Pix, and the side surface of the opening has a slope having a forward taper side surface portion TSF. The slope of the bank layer 48 surrounds each pixel. The bank layer 48 is formed using, for example, a photosensitive resin (for example, polyimide or acrylic resin). The thickness of the bank layer 48 is, for example, 1 μm or more and 2 μm or less. The inclination angle θb of the slope of the bank layer 48 is 60 ° or less. If the inclination angle θb of the slope of the bank layer 48 is more than 60 °, defects may occur in the layer located above the bank layer 48.
 有機バリア層14Aは、バンク層48を覆い、平坦な表面を有している。有機バリア層14Aの厚さは、バンク層48の厚さよりも大きく、例えば、3μm以上20μm以下である。第2無機バリア層16は、有機バリア層14Aの平坦な表面に形成されている。有機バリア層14Aの厚さは、3μm以上10μm以下であってもよい。厚さが10μmを超える有機バリア層14Aを形成するためには、比較的粘度の高い樹脂材料が必要になる。粘度の高い樹脂材料は、第1無機バリア層12の複数の微細な凸部の隙間に充填されないことがある。樹脂材料が複数の微細な凸部の隙間に充填されないと、十分な反射防止効果が得られないことがある。有機バリア層14Aの厚さが3μm以上10μm以下であると、比較的粘度の低い樹脂材料で形成され得るので、第1無機バリア層12の複数の微細な凸部の間に樹脂材料を十部に充填することができる。このような厚さの有機バリア層14Aは、例えば、インクジェット法、スリットコート法で形成することができる。 The organic barrier layer 14A covers the bank layer 48 and has a flat surface. The thickness of the organic barrier layer 14A is larger than the thickness of the bank layer 48, for example, 3 μm or more and 20 μm or less. The second inorganic barrier layer 16 is formed on the flat surface of the organic barrier layer 14A. The thickness of the organic barrier layer 14A may be 3 μm or more and 10 μm or less. In order to form the organic barrier layer 14A having a thickness of more than 10 μm, a resin material having a relatively high viscosity is required. The highly viscous resin material may not fill the gaps between the plurality of fine protrusions of the first inorganic barrier layer 12. If the resin material is not filled in the gaps between the plurality of fine protrusions, a sufficient antireflection effect may not be obtained. When the thickness of the organic barrier layer 14A is 3 μm or more and 10 μm or less, it can be formed of a resin material having a relatively low viscosity. Can be filled in. The organic barrier layer 14A having such a thickness can be formed by, for example, an inkjet method or a slit coating method.
 第1無機バリア層12は、図2Aを参照して説明した様に、第1サブバリア層12saと、第1サブバリア層12sa上に形成され、有機バリア層14に接する第2サブバリア層12sbとを有しており、第1無機バリア層12の有機バリア層14に接する表面12Sは、複数の微細な凸部を有し、複数の微細な凸部の高さは20nm以上80nm以下であり、複数の微細な凸部の幅は20nm以上80nm以下である。さらに、複数の微細な凸部間の間隔は20nm以上80nm以下である。図7Aを参照して後述するように、第2サブバリア層12sbは、離散的に分布した複数の島状部を有し、複数の島状部が上記複数の微細な凸部を形成してもよい。第2サブバリア層12sbは、例えば、SiNまたはSiONで形成されている。このとき、SiNまたはSiONの屈折率は1.70以上2.10以下であることが好ましい。 As described with reference to FIG. 2A, the first inorganic barrier layer 12 has a first sub-barrier layer 12sa and a second sub-barrier layer 12sb formed on the first sub-barrier layer 12sa and in contact with the organic barrier layer 14. The surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine convex portions, and the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and a plurality of fine protrusions are formed. The width of the fine convex portion is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine protrusions is 20 nm or more and 80 nm or less. As will be described later with reference to FIG. 7A, the second sub-barrier layer 12sb has a plurality of discretely distributed island-shaped portions, and even if the plurality of island-shaped portions form the plurality of fine convex portions. Good. The second sub-barrier layer 12sb is made of, for example, SiN or SiON. At this time, the refractive index of SiN or SiON is preferably 1.70 or more and 2.10 or less.
 第1サブバリア層12saの表面粗さ(例えば、算術平均粗さRa(JISによる))は、例えば5nm未満である。第1サブバリア層12saは、例えば、厚さが10nm以上30nm以下のAl23層である。第1サブバリア層12saは、例えば、厚さが200nm以上400nm以下のSiN層またはSiON層であってもよい。第2無機バリア層16は、例えば、厚さが200nm以上400nm以下のSiN層またはSiON層である。 The surface roughness of the first sub-barrier layer 12sa (for example, arithmetic mean roughness Ra (according to JIS)) is, for example, less than 5 nm. The first sub-barrier layer 12sa is, for example, an Al 2 O 3 layer having a thickness of 10 nm or more and 30 nm or less. The first sub-barrier layer 12sa may be, for example, a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less. The second inorganic barrier layer 16 is, for example, a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
 第1無機バリア層12および第2無機バリア層16は、例えば、マスクを用いたPECVD法で、アクティブ領域R1を覆うように所定の領域だけに選択的に形成される。有機バリア層14Aは、第1無機バリア層12と第2無機バリア層16とが直接接触する無機バリア層接合部によって包囲される領域内にのみ形成されている。したがって、有機バリア層14Aが水分の侵入経路となって、OLED表示装置のアクティブ領域R1に水分が到達することがない。有機バリア層14Aは、例えば、インクジェット法を用いて所定の領域に、無色透明の光硬化性樹脂(例えば、アクリル樹脂またはエポキシ樹脂)で形成される。アクリル樹脂の屈折率は、例えば、1.48以上1.55以下である。エポキシ樹脂の屈折率は、例えば、1.55以上1.61以下である。 The first inorganic barrier layer 12 and the second inorganic barrier layer 16 are selectively formed only in a predetermined region so as to cover the active region R1 by, for example, a PECVD method using a mask. The organic barrier layer 14A is formed only in the region surrounded by the inorganic barrier layer joint where the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact with each other. Therefore, the organic barrier layer 14A serves as an intrusion route for moisture, and the moisture does not reach the active region R1 of the OLED display device. The organic barrier layer 14A is formed of a colorless and transparent photocurable resin (for example, an acrylic resin or an epoxy resin) in a predetermined region by using, for example, an inkjet method. The refractive index of the acrylic resin is, for example, 1.48 or more and 1.55 or less. The refractive index of the epoxy resin is, for example, 1.55 or more and 1.61 or less.
 第1無機バリア層12を形成する前または形成している間に、アクティブ領域R1内にパーティクル(典型的には高さが0.5μm以上5μm以下)Pが存在すると、図4Bに模式的に示す様に、第1無機バリア層12にクラック(欠陥)12cが形成されることがある。これは、パーティクルPの表面から成長する第1無機バリア層12aと、OLED3の表面の平坦部分から成長する第1無機バリア層12bとが衝突(インピンジ)するために生じたと考えられる。このようなクラック12cが存在すると、TFE構造のバリア性が低下する。十分な厚さを有する有機バリア層14Aで第1無機バリア層12を覆うことによって、TFE構造10A1は、バリア性の低下を抑制することができる。 The presence of particles (typically 0.5 μm or more and 5 μm or less) P in the active region R1 before or during the formation of the first inorganic barrier layer 12 is schematically shown in FIG. 4B. As shown, cracks (defects) 12c may be formed in the first inorganic barrier layer 12. It is considered that this is caused by the collision (impingement) between the first inorganic barrier layer 12a growing from the surface of the particles P and the first inorganic barrier layer 12b growing from the flat portion of the surface of the OLED 3. The presence of such cracks 12c reduces the barrier property of the TFE structure. By covering the first inorganic barrier layer 12 with an organic barrier layer 14A having a sufficient thickness, the TFE structure 10A1 can suppress a decrease in barrier property.
 次に、図4Cを参照して、引出し配線30上のTFE構造10A1の構造を説明する。図4Cは、図3中の4C-4C'線に沿った断面図であり、引出し配線30のアクティブ領域R1側の部分32の断面図である。 Next, the structure of the TFE structure 10A1 on the lead-out wiring 30 will be described with reference to FIG. 4C. FIG. 4C is a cross-sectional view taken along the line 4C-4C'in FIG. 3, and is a cross-sectional view of a portion 32 of the drawer wiring 30 on the active region R1 side.
 有機バリア層14Aは、図3におけるTFE構造10の内のアクティブ領域(図2中の破線で囲まれた領域)R1内にのみ形成されており、アクティブ領域R1の外側に形成されていない。したがって、アクティブ領域R1の外側では、第1無機バリア層12と第2無機バリア層16とが直接接触している。すなわち、有機バリア層14Aは、上述したように、第1無機バリア層12と第2無機バリア層16とが直接接触する無機バリア層接合部によって包囲される。したがって、図4Cに示すように、引出し配線30のアクティブ領域R1側の部分32は、第1無機バリア層12と第2無機バリア層16とによって覆われている。 The organic barrier layer 14A is formed only in the active region (region surrounded by the broken line in FIG. 2) R1 in the TFE structure 10 in FIG. 3, and is not formed outside the active region R1. Therefore, outside the active region R1, the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact with each other. That is, as described above, the organic barrier layer 14A is surrounded by the inorganic barrier layer joint portion in which the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact with each other. Therefore, as shown in FIG. 4C, the portion 32 of the drawer wiring 30 on the active region R1 side is covered with the first inorganic barrier layer 12 and the second inorganic barrier layer 16.
 次に、図5A、図5Bおよび図5Cを参照して、比較的薄い有機バリア層14Bを有するTFE構造10A2を備える、実施形態1によるOLED表示装置100A2の構造を説明する。図5Aは図3中の4A-4A'線に沿った画素Pixを含む断面図であり、図5Bは図3中の4A-4A'線に沿ったパーティクルPを含む断面図であり、図5Cは図3中の4C-4C'線に沿った断面図である。 Next, the structure of the OLED display device 100A2 according to the first embodiment will be described with reference to FIGS. 5A, 5B and 5C, which comprises a TFE structure 10A2 having a relatively thin organic barrier layer 14B. 5A is a cross-sectional view including the pixel Pix along the 4A-4A'line in FIG. 3, and FIG. 5B is a cross-sectional view including the particles P along the 4A-4A' line in FIG. 3C. Is a cross-sectional view taken along the line 4C-4C'in FIG.
 図5Aに示すTFE構造10A2の有機バリア層14Bは、離散的に分布する複数の中実部を有する。複数の中実部は、バンク層48の開口部の側面上の第1無機バリア層12の斜面から画素Pix内の周辺に至る画素周辺中実部14Baを有する。 The organic barrier layer 14B of the TFE structure 10A2 shown in FIG. 5A has a plurality of discretely distributed solid parts. The plurality of solid portions have a pixel peripheral solid portion 14Ba extending from the slope of the first inorganic barrier layer 12 on the side surface of the opening of the bank layer 48 to the periphery within the pixel Pix.
 有機バリア層14Bの厚さ(ここでは画素周辺中実部14Baの厚さ)は、50nm以上200nm未満であることが好ましい。画素周辺中実部14Baの厚さが大きくなると、離散的に分散した中実部が、連続した膜となってしまう。有機バリア層14Bが離散的に分散した中実部を有するOLED表示装置100A2は、比較的厚い有機バリア層14Aを有するOLED表示装置100Aよりも、フレキシビリティに優れるという利点を有する。 The thickness of the organic barrier layer 14B (here, the thickness of the solid portion 14Ba around the pixel) is preferably 50 nm or more and less than 200 nm. When the thickness of the solid portion 14Ba around the pixel increases, the discretely dispersed solid portion becomes a continuous film. The OLED display device 100A2 having a solid portion in which the organic barrier layer 14B is discretely dispersed has an advantage that it is superior in flexibility to the OLED display device 100A having a relatively thick organic barrier layer 14A.
 また、図5Bに示す様に、パーティクルPが存在すると、第1無機バリア層12のクラック12cを充填するように中実部14Bbが形成され、かつ、中実部14Bbの表面は、パーティクルP上の第1無機バリア層12aの表面と、OLED3の平坦部上の第1無機バリア層12bとの表面を連続的に滑らかに連結する。有機バリア層14Bは、液状の光硬化性樹脂を硬化することによって形成されるので、表面張力によって凹状の表面を形成する。このとき、光硬化性樹脂は、第1無機バリア層12に対して良好な濡れ性を示している。光硬化性樹脂の第1無機バリア層12に対する濡れ性が悪いと、逆に凸状になることがある。なお、有機バリア層14がパーティクルP上の第1無機バリア層12aの表面にも薄く形成されることがある。 Further, as shown in FIG. 5B, when the particles P are present, the solid portion 14Bb is formed so as to fill the cracks 12c of the first inorganic barrier layer 12, and the surface of the solid portion 14Bb is on the particles P. The surface of the first inorganic barrier layer 12a and the surface of the first inorganic barrier layer 12b on the flat portion of the OLED 3 are continuously and smoothly connected. Since the organic barrier layer 14B is formed by curing a liquid photocurable resin, a concave surface is formed by surface tension. At this time, the photocurable resin exhibits good wettability with respect to the first inorganic barrier layer 12. If the photocurable resin has poor wettability with respect to the first inorganic barrier layer 12, it may become convex on the contrary. The organic barrier layer 14 may also be thinly formed on the surface of the first inorganic barrier layer 12a on the particles P.
 凹状の表面を有する中実部14Bbによって、パーティクルP上の第1無機バリア層12aの表面と、平坦部上の第1無機バリア層12bの表面とが連続的に滑らかに連結されるので、この上に、欠陥の無い、緻密な膜で第2無機バリア層16を形成することができる。このように、有機バリア層14Bによって、パーティクルPが存在しても、TFE構造10A2のバリア性を維持することができる。 The solid portion 14Bb having a concave surface continuously and smoothly connects the surface of the first inorganic barrier layer 12a on the particles P and the surface of the first inorganic barrier layer 12b on the flat portion. On top of this, the second inorganic barrier layer 16 can be formed with a dense film without defects. As described above, the organic barrier layer 14B can maintain the barrier property of the TFE structure 10A2 even in the presence of the particles P.
 次に、図5Cを参照して、引出し配線30上のTFE構造10A2の構造を説明する。図5Cは、図3中の4C-4C'線に沿った断面図であり、引出し配線30のアクティブ領域R1側の部分32の断面図である。 Next, the structure of the TFE structure 10A2 on the lead-out wiring 30 will be described with reference to FIG. 5C. FIG. 5C is a cross-sectional view taken along the line 4C-4C'in FIG. 3, and is a cross-sectional view of a portion 32 of the leader wiring 30 on the active region R1 side.
 図5Cに示すように、有機バリア層14Bは、引出し配線30の部分32の断面形状を反映した第1無機バリア層12の表面の凸部の周辺に形成された中実部14Bcを含む。中実部14Bcが存在することによって、第1無機バリア層12の段差上に、欠陥の無い、緻密な膜で第2無機バリア層16を形成することができる。 As shown in FIG. 5C, the organic barrier layer 14B includes a solid portion 14Bc formed around a convex portion on the surface of the first inorganic barrier layer 12 that reflects the cross-sectional shape of the portion 32 of the lead-out wiring 30. Due to the presence of the solid portion 14Bc, the second inorganic barrier layer 16 can be formed on the step of the first inorganic barrier layer 12 with a dense film having no defects.
 有機バリア層14Bは、例えば、上記特許文献1または2に記載の方法で形成され得る。例えば、チャンバー内で、蒸気または霧状の有機材料(例えばアクリルモノマー)を、室温以下の温度に維持された素子基板上に供給し、素子基板上で凝縮させ、液状になった有機材料の毛細管現象または表面張力によって、第1無機バリア層12の凸部の側面と平坦部との境界部に偏在させる。その後、有機材料に例えば紫外線を照射することによって、凸部の周辺の境界部に有機バリア層(例えばアクリル樹脂層)14Bの中実部を形成する。この方法によって形成される有機バリア層14Bは、平坦部には中実部が実質的に存在しない。このとき、バンク層48の斜面上にも液膜が形成されるように、光硬化性樹脂の粘度、斜面に対する濡れ性等が制御される。斜面の表面を改質してもよい。また、特許文献3に記載されているように、最初に成膜する樹脂層の厚さを調整する(例えば、100nm未満とする)、および/または、アッシング条件(時間を含む)を調整することによって、有機バリア層14Bを形成することもできる。 The organic barrier layer 14B can be formed, for example, by the method described in Patent Document 1 or 2 above. For example, in a chamber, a vapor or atomized organic material (eg, acrylic monomer) is supplied onto an element substrate maintained at a temperature below room temperature and condensed on the element substrate to form a liquid capillary tube of the organic material. Due to the phenomenon or surface tension, the first inorganic barrier layer 12 is unevenly distributed at the boundary between the side surface of the convex portion and the flat portion. Then, by irradiating the organic material with, for example, ultraviolet rays, a solid portion of the organic barrier layer (for example, an acrylic resin layer) 14B is formed at the boundary portion around the convex portion. The organic barrier layer 14B formed by this method has substantially no solid portion in the flat portion. At this time, the viscosity of the photocurable resin, the wettability with respect to the slope, and the like are controlled so that the liquid film is also formed on the slope of the bank layer 48. The surface of the slope may be modified. Further, as described in Patent Document 3, the thickness of the resin layer to be first formed is adjusted (for example, less than 100 nm), and / or the ashing conditions (including time) are adjusted. It is also possible to form the organic barrier layer 14B.
 なお、例えば、端子38から引出し配線30に沿って中実部14Bcが形成されると、中実部14Bcが水分の侵入経路となって、OLED表示装置100A2のアクティブ領域R1に水分が到達することがある。これを防止するために、引出し配線30上に形成されるTFE構造10A2の一部に、第1無機バリア層12と第2無機バリア層16とが直接接触する無機バリア層接合部を形成する。このような無機バリア層接合部は、例えば、引出し配線30のテーパー角を例えば70°以下にする、あるいは、光硬化性樹脂を硬化させるまでに赤外線等を照射して、光硬化性樹脂を気化させる、などすればよい。 For example, when the solid portion 14Bc is formed from the terminal 38 along the lead-out wiring 30, the solid portion 14Bc serves as an intrusion route for moisture, and the moisture reaches the active region R1 of the OLED display device 100A2. There is. In order to prevent this, an inorganic barrier layer joint portion in which the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact is formed in a part of the TFE structure 10A2 formed on the drawer wiring 30. In such an inorganic barrier layer joint, for example, the taper angle of the lead wire 30 is set to 70 ° or less, or the photocurable resin is vaporized by irradiating infrared rays or the like until the photocurable resin is cured. You can let them do it.
 有機バリア層14Bは、例えば、スプレイ法、スピンコート法、スリットコート法、スクリーン印刷またはインクジェット法を用いて形成してもよい。アッシング工程をさらに含んでもよい。有機バリア層を、感光性樹脂を用いて形成し、マスク露光を行ってもよい。マスク露光によって、画素周辺中実部14Baを形成するとともに、第1無機バリア層12と第2無機バリア層16とが直接接触する無機バリア層接合部を形成してもよい。 The organic barrier layer 14B may be formed by using, for example, a spray method, a spin coating method, a slit coating method, screen printing or an inkjet method. An ashing step may be further included. The organic barrier layer may be formed by using a photosensitive resin and mask exposure may be performed. By mask exposure, a solid portion 14Ba around the pixel may be formed, and an inorganic barrier layer joint portion in which the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact may be formed.
 図6Aに、OLED表示装置100A1におけるTFE構造10A1の模式的な断面図を示し、図6Bに、OLED表示装置100A2におけるTFE構造10A2の模式的な断面図を示す。 FIG. 6A shows a schematic cross-sectional view of the TFE structure 10A1 in the OLED display device 100A1, and FIG. 6B shows a schematic cross-sectional view of the TFE structure 10A2 in the OLED display device 100A2.
 図6Aに示すTFE構造10A1の比較的厚い有機バリア層14Aは、バンク層48を覆い、平坦な表面を有している。第1無機バリア層12の有機バリア層14Aに接する表面12Sは、複数の微細な凸部を有している。図6Bに示すTFE構造10A2の比較的薄い有機バリア層14Bは、離散的に分布する複数の中実部を有し、バンク層48の開口部の側面上の第1無機バリア層12の斜面から画素Pix内の周辺に至る画素周辺中実部14Baを有している。第1無機バリア層12の有機バリア層14Bに接する表面12Sは、複数の微細な凸部を有している。 The relatively thick organic barrier layer 14A of the TFE structure 10A1 shown in FIG. 6A covers the bank layer 48 and has a flat surface. The surface 12S of the first inorganic barrier layer 12 in contact with the organic barrier layer 14A has a plurality of fine protrusions. The relatively thin organic barrier layer 14B of the TFE structure 10A2 shown in FIG. 6B has a plurality of discretely distributed solid portions from the slope of the first inorganic barrier layer 12 on the side surface of the opening of the bank layer 48. It has a pixel peripheral solid portion 14Ba that extends to the periphery within the pixel Pix. The surface 12S in contact with the organic barrier layer 14B of the first inorganic barrier layer 12 has a plurality of fine protrusions.
 次に、図7Aを参照して、実施形態1によるOLED表示装置100A1のTFE構造10A1およびOLED表示装置100A2のTFE構造10A2における第1無機バリア層12の構造および形成方法と、第1無機バリア層12と有機バリア層14Bとの界面における反射が抑制されることを説明する。 Next, with reference to FIG. 7A, the structure and formation method of the first inorganic barrier layer 12 in the TFE structure 10A1 of the OLED display device 100A1 and the TFE structure 10A2 of the OLED display device 100A2 according to the first embodiment, and the first inorganic barrier layer. It will be explained that the reflection at the interface between 12 and the organic barrier layer 14B is suppressed.
 図7Aに示す様に、第1無機バリア層12は、第1サブバリア層12saと、第1サブバリア層12sa上に形成され、有機バリア層14に接する第2サブバリア層12sbとを有している。第1無機バリア層12の有機バリア層14に接する表面12Sは、複数の微細な凸部を有し、複数の微細な凸部の高さは20nm以上80nm以下であり、複数の微細な凸部の幅は20nm以上80nm以下である。さらに、複数の微細な凸部間の間隔は20nm以上80nm以下である。ここで例示するように、第2サブバリア層12sbは、離散的に分布した複数の島状部を有し、複数の島状部が上記複数の微細な凸部を形成してもよい。このとき、第1無機バリア層12の表面12Sは、第2サブバリア層12sbの離散的に分布した複数の島状部の表面と、第1サブバリア層12saの表面の内、第2サブバリア層12sbを構成する複数の島状部が形成されていない部分とで構成されることになる。 As shown in FIG. 7A, the first inorganic barrier layer 12 has a first sub-barrier layer 12sa and a second sub-barrier layer 12sb formed on the first sub-barrier layer 12sa and in contact with the organic barrier layer 14. The surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine convex portions, the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and the plurality of fine convex portions. The width of is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine protrusions is 20 nm or more and 80 nm or less. As illustrated here, the second sub-barrier layer 12sb may have a plurality of discretely distributed island-shaped portions, and the plurality of island-shaped portions may form the plurality of fine convex portions. At this time, the surface 12S of the first inorganic barrier layer 12 includes the surface of a plurality of discretely distributed island-shaped portions of the second sub-barrier layer 12sb and the second sub-barrier layer 12sb among the surfaces of the first sub-barrier layer 12sa. It will be composed of a plurality of constituent island-shaped portions that are not formed.
 第1サブバリア層12saは、例えば、厚さが10nm以上30nm以下のAl23層(アルミナ層)である。バリア性に優れた緻密な膜質のAl23層は、ALD(Atomic Layer Deposition)法で形成することによって得られる。第1サブバリア層12saは、厚さが200nm以上400nm以下のSiN層またはSiON層であってもよい。SiN層またはSiON層は、PECVD法で形成され得る。このように形成したとき、SiNまたはSiONの屈折率は1.70以上2.10以下である。 The first sub-barrier layer 12sa is, for example, an Al 2 O 3 layer (alumina layer) having a thickness of 10 nm or more and 30 nm or less. A dense film-like Al 2 O 3 layer having excellent barrier properties can be obtained by forming it by the ALD (Atomic Layer Deposition) method. The first sub-barrier layer 12sa may be a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less. The SiN layer or the SiON layer can be formed by the PECVD method. When formed in this way, the refractive index of SiN or SiON is 1.70 or more and 2.10 or less.
 第2サブバリア層12sbは、例えばSiNまたはSiONで形成される。第2サブバリア層12sbもPECVD法で形成され得る。第1サブバリア層12saをSiN層またはSiON層で形成するとき、PECVD法で連続して、第1サブバリア層12saと第2サブバリア層12sbとを形成することができるため、スループットを高め、製造コストを低減することができる。PECVD法で連続して形成する場合、第1サブバリア層12saを形成した後、成膜スピードを上げることによって、および/または成膜温度(素子基板の温度)を調節することによって、離散的に分布した複数の島状部を有する第2サブバリア層12sbを得ることができる。成膜温度については、適正な素子基板温度から外れるように温度を上昇させても、あるいは、温度を下降させてもよいが、有機EL素子への熱的な影響を考慮すると、温度を下げる方向で調節することが好ましい。また、第2サブバリア層12sbをSiON層で形成する場合には、供給する酸素濃度を上げてもよい。このようにして、緻密でバリア性の高い第1サブバリア層12saと、離散的に分布した複数の島状部を有する第2サブバリア層12sbとをそれぞれ所望の厚さで形成することができ、膜の粗密を連続的に変化させる場合に比べ、耐湿信頼性の確保と、光の反射の抑制とをより確実に達成することができる。 The second sub-barrier layer 12sb is formed of, for example, SiN or SiON. The second sub-barrier layer 12sb can also be formed by the PECVD method. When the first sub-barrier layer 12sa is formed of the SiN layer or the SiON layer, the first sub-barrier layer 12sa and the second sub-barrier layer 12sb can be continuously formed by the PECVD method, so that the throughput is increased and the manufacturing cost is increased. Can be reduced. When continuously formed by the PECVD method, the first sub-barrier layer 12sa is formed and then distributed discretely by increasing the film forming speed and / or adjusting the film forming temperature (element substrate temperature). A second sub-barrier layer 12sb having a plurality of island-shaped portions can be obtained. Regarding the film formation temperature, the temperature may be raised or lowered so as to deviate from the appropriate element substrate temperature, but in consideration of the thermal effect on the organic EL device, the temperature is lowered. It is preferable to adjust with. Further, when the second sub-barrier layer 12sb is formed of the SiON layer, the oxygen concentration to be supplied may be increased. In this way, the first sub-barrier layer 12sa, which is dense and has a high barrier property, and the second sub-barrier layer 12sb, which has a plurality of discretely distributed island-shaped portions, can be formed with desired thicknesses. Compared with the case where the density of the light is continuously changed, it is possible to secure the reliability of moisture resistance and suppress the reflection of light more reliably.
 第1無機バリア層12の有機バリア層14に接する表面12Sは、複数の微細な凸部を有し、複数の微細な凸部の高さは20nm以上80nm以下であり、複数の微細な凸部の幅は20nm以上80nm以下である。さらに、複数の微細な凸部間の間隔は20nm以上80nm以下である。このような構成を有する複数の微細な凸部およびその間の平坦部は、可視光の下限域(400nm程度)に対しても十分に小さく、光を反射させることが無い。また、複数の微細な凸部の間にはそれよりも屈折率が小さい有機バリア層が充填されるため、平均屈折率を緩やかに低下させることができる。したがって、屈折率に起因する反射を低減・解消することができる。 The surface 12S in contact with the organic barrier layer 14 of the first inorganic barrier layer 12 has a plurality of fine convex portions, the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and the plurality of fine convex portions. The width of is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine protrusions is 20 nm or more and 80 nm or less. The plurality of fine convex portions having such a configuration and the flat portions between them are sufficiently small even with respect to the lower limit region of visible light (about 400 nm) and do not reflect light. Further, since the organic barrier layer having a refractive index smaller than that is filled between the plurality of fine convex portions, the average refractive index can be gradually lowered. Therefore, the reflection caused by the refractive index can be reduced or eliminated.
 実施形態1によるOLED表示装置100A1およびOLED表示装置100A2は、図7Bに示す様に、第1無機バリア層12上に第2無機バリア層16が直接形成される領域を有する。第1無機バリア層12と第2無機バリア層16とを同じ材料で形成すれば、第1無機バリア層12と第2無機バリア層16との界面で光が反射することはない。なお、第1サブバリア層12saをAl23層で形成し、第2サブバリア層12sbをSiN層またはSiON層で形成した場合であっても、Al23の屈折率はおよそ1.80であり、SiNの屈折率は前述したようにおよそ1.85であるので、屈折率差はほとんどなく界面での反射は非常に少ない。したがって、複数の微細な凸部は、それよりも屈折率が小さい有機バリア層と作用して平均屈折率を緩やかに低下させるので、屈折率に起因する反射を低減・解消することができる。 As shown in FIG. 7B, the OLED display device 100A1 and the OLED display device 100A2 according to the first embodiment have a region in which the second inorganic barrier layer 16 is directly formed on the first inorganic barrier layer 12. If the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are made of the same material, light will not be reflected at the interface between the first inorganic barrier layer 12 and the second inorganic barrier layer 16. Even when the first sub-barrier layer 12sa is formed of the Al 2 O 3 layer and the second sub-barrier layer 12 sb is formed of the SiN layer or the SiON layer, the refractive index of Al 2 O 3 is about 1.80. Since the refractive index of SiN is about 1.85 as described above, there is almost no difference in the refractive index and the reflection at the interface is very small. Therefore, since the plurality of fine convex portions act on the organic barrier layer having a smaller refractive index to gradually lower the average refractive index, the reflection caused by the refractive index can be reduced or eliminated.
 第1無機バリア層12の表面の微細な凸部の高さは80nm以下であるので、その上に直接、第2無機バリア層16を形成しても、第2無機バリア層16の膜厚を200nm以上、より好ましくは、第1無機バリア層12の表面の微細な凸部の高さよりも300nm以上大きくする(例えば凸部の高さが80nmのとき、第2無機バリア層16の膜厚を380nm以上とする)ことによって、第2無機バリア層16の水分・酸素に対するバリア性が低下することなく、良好なバリア性を有するTFE構造を得ることができる。 Since the height of the fine convex portion on the surface of the first inorganic barrier layer 12 is 80 nm or less, even if the second inorganic barrier layer 16 is formed directly on the height, the thickness of the second inorganic barrier layer 16 can be increased. 200 nm or more, more preferably 300 nm or more larger than the height of the fine convex portion on the surface of the first inorganic barrier layer 12 (for example, when the height of the convex portion is 80 nm, the thickness of the second inorganic barrier layer 16 is increased. By setting the diameter to 380 nm or more), a TFE structure having a good barrier property can be obtained without lowering the barrier property of the second inorganic barrier layer 16 against water and oxygen.
 次に、図8Aおよび図8Bを参照して、実施形態2によるOLED表示装置100B1およびOLED表示装置100B2を説明する。図8Aに、OLED表示装置100B1におけるTFE構造10B1の模式的な断面図を示し、図8Bに、OLED表示装置100B2におけるTFE構造10B2の模式的な断面図を示す。 Next, the OLED display device 100B1 and the OLED display device 100B2 according to the second embodiment will be described with reference to FIGS. 8A and 8B. FIG. 8A shows a schematic cross-sectional view of the TFE structure 10B1 in the OLED display device 100B1, and FIG. 8B shows a schematic cross-sectional view of the TFE structure 10B2 in the OLED display device 100B2.
 図8Aに示すTFE構造10B1の比較的厚い有機バリア層14Aは、バンク層48を覆い、平坦な表面を有している。第1無機バリア層12の有機バリア層14Aに接する表面12Sは、複数の微細な凸部を有している。さらに、有機バリア層14Aの第2無機バリア層16に接する第1表面14ASは、複数の微細な第1凸部を有し、複数の微細な第1凸部の高さは20nm以上80nm以下であり、複数の微細な第1凸部の幅は20nm以上80nm以下である。さらに、複数の微細な第1凸部間の間隔は20nm以上80nm以下である。また、第2無機バリア層16が有する第2表面16Sは、複数の微細な第2凸部を有し、複数の微細な第2凸部の高さは20nm以上80nm以下であり、複数の微細な第2凸部の幅は20nm以上80nm以下である。さらに、複数の微細な第2凸部間の間隔は20nm以上80nm以下である。複数の微細な第2凸部間の空隙には空気よりも屈折率が高く、複数の微細な第2凸部よりも屈折率が低い、例えば接着層が充填されていることが好ましい。このように可視光の波長よりも十分に小さい範囲で複数の微細な第1凸部および複数の微細な第2凸部を形成することによって、それぞれの凸部の頂部および側面、さらに互いに隣接する凸部と凸部との間の平坦部における反射を効果的に抑制することができる。 The relatively thick organic barrier layer 14A of the TFE structure 10B1 shown in FIG. 8A covers the bank layer 48 and has a flat surface. The surface 12S of the first inorganic barrier layer 12 in contact with the organic barrier layer 14A has a plurality of fine protrusions. Further, the first surface 14AS in contact with the second inorganic barrier layer 16 of the organic barrier layer 14A has a plurality of fine first convex portions, and the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. The width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less. Further, the second surface 16S of the second inorganic barrier layer 16 has a plurality of fine second convex portions, and the height of the plurality of fine second convex portions is 20 nm or more and 80 nm or less, and the plurality of fine parts are present. The width of the second convex portion is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions is 20 nm or more and 80 nm or less. It is preferable that the voids between the plurality of fine second convex portions are filled with an adhesive layer having a higher refractive index than air and a lower refractive index than the plurality of fine second convex portions, for example. By forming a plurality of fine first convex portions and a plurality of fine second convex portions in a range sufficiently smaller than the wavelength of visible light in this way, the tops and side surfaces of the respective convex portions, and further adjacent to each other. It is possible to effectively suppress the reflection in the flat portion between the convex portion and the convex portion.
 図8Bに示すTFE構造10B2の比較的薄い有機バリア層14Bは、離散的に分布する複数の中実部を有し、バンク層48の開口部の側面上の第1無機バリア層12の斜面から画素Pix内の周辺に至る画素周辺中実部14Baを有している。第1無機バリア層12の有機バリア層14Bに接する表面12Sは、複数の微細な凸部を有している。さらに、有機バリア層14Bの第2無機バリア層16に接する第1表面14BSは、複数の微細な第1凸部を有し、複数の微細な第1凸部の高さは20nm以上80nm以下であり、複数の微細な第1凸部の幅は20nm以上80nm以下である。さらに、複数の微細な第1凸部間の間隔は20nm以上80nm以下である。また、第2無機バリア層16が有する第2表面16Sは、複数の微細な第2凸部を有し、複数の微細な第2凸部の高さは20nm以上80nm以下であり、複数の微細な第2凸部の幅は20nm以上80nm以下である。さらに、複数の微細な第2凸部間の間隔は20nm以上80nm以下である。 The relatively thin organic barrier layer 14B of the TFE structure 10B2 shown in FIG. 8B has a plurality of discretely distributed solid portions from the slope of the first inorganic barrier layer 12 on the side surface of the opening of the bank layer 48. It has a pixel peripheral solid portion 14Ba that extends to the periphery within the pixel Pix. The surface 12S in contact with the organic barrier layer 14B of the first inorganic barrier layer 12 has a plurality of fine protrusions. Further, the first surface 14BS in contact with the second inorganic barrier layer 16 of the organic barrier layer 14B has a plurality of fine first convex portions, and the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. The width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less. Further, the second surface 16S of the second inorganic barrier layer 16 has a plurality of fine second convex portions, and the height of the plurality of fine second convex portions is 20 nm or more and 80 nm or less, and the plurality of fine parts are present. The width of the second convex portion is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions is 20 nm or more and 80 nm or less.
 図9は、TFE構造10B(10B1、10B2)における有機バリア層14Aと第2無機バリア層16との界面(有機バリア層14Aの表面14AS)および第2無機バリア層16の表面16Sを示す模式的な断面図である。 FIG. 9 is a schematic view showing the interface between the organic barrier layer 14A and the second inorganic barrier layer 16 (surface 14AS of the organic barrier layer 14A) and the surface 16S of the second inorganic barrier layer 16 in the TFE structure 10B (10B1, 10B2). It is a cross-sectional view.
 図9に模式的に示す様に、有機バリア層14A、14Bの第2無機バリア層16に接する第1表面14AS、14BSは、複数の微細な第1凸部を有し、複数の微細な第1凸部の高さは20nm以上80nm以下であり、複数の微細な第1凸部の幅は20nm以上80nm以下である。さらに、複数の微細な第1凸部間の間隔は20nm以上80nm以下である。また、第2無機バリア層16が有する第2表面16Sは、有機バリア層14A、14Bの第1表面14AS、14BSの複数の微細な第1凸部(表面粗さ)の影響を受け、複数の微細な第2凸部を有している。複数の微細な第2凸部の高さは20nm以上80nm以下であり、複数の微細な第2凸部の幅は20nm以上80nm以下である。さらに、複数の微細な第2凸部間の間隔は20nm以上80nm以下である。複数の微細な第1凸部および第2凸部は、それぞれ有機バリア層との間、接着層との間で緩やかに変化する平均屈折率の層を形成するので、屈折率に起因する反射を低減・解消することができる。したがって、有機バリア層14Aと第2無機バリア層16との界面における反射および第2無機バリア層16の第2表面16Sにおける反射も低減される。実施形態2のOLED表示装置は、実施形態1のOLED表示装置よりもさらにTFE構造における反射を低減することができる。 As schematically shown in FIG. 9, the first surfaces 14AS and 14BS in contact with the second inorganic barrier layers 16 of the organic barrier layers 14A and 14B have a plurality of fine first convex portions and a plurality of fine first protrusions. The height of the one convex portion is 20 nm or more and 80 nm or less, and the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less. Further, the second surface 16S of the second inorganic barrier layer 16 is affected by a plurality of fine first convex portions (surface roughness) of the first surfaces 14AS and 14BS of the organic barrier layers 14A and 14B, and a plurality of them. It has a fine second convex portion. The height of the plurality of fine second convex portions is 20 nm or more and 80 nm or less, and the width of the plurality of fine second convex portions is 20 nm or more and 80 nm or less. Further, the distance between the plurality of fine second convex portions is 20 nm or more and 80 nm or less. Since the plurality of fine first convex portions and second convex portions each form a layer having an average refractive index that gradually changes between the organic barrier layer and the adhesive layer, reflection due to the refractive index is caused. It can be reduced or eliminated. Therefore, the reflection at the interface between the organic barrier layer 14A and the second inorganic barrier layer 16 and the reflection at the second surface 16S of the second inorganic barrier layer 16 are also reduced. The OLED display device of the second embodiment can further reduce the reflection in the TFE structure as compared with the OLED display device of the first embodiment.
 有機バリア層14A、14Bの表面に微細な第1凸部を形成する方法として、例えば、以下の方法を例示することができる。 As a method for forming a fine first convex portion on the surfaces of the organic barrier layers 14A and 14B, for example, the following method can be exemplified.
 公知の方法で有機バリア層14A、14Bとなる有機樹脂層を形成した後、O2、O3またはN2Oガスをプラズマ化し、高エネルギー状態の酸素ラジカルを生成し、酸素ラジカルを有機樹脂層に照射する。照射された酸素ラジカルは、有機樹脂層を構成する炭素と結合し、CO2を生成し、有機樹脂層を分解・気化させる(アッシングということがある)。このときのプラズマエネルギー、酸素ラジカルの照射条件を調整することにより、有機バリア層表面に、高さ、幅、およびそれらの間隔がそれぞれ独立に20nm以上80nm以下の凹凸構造を形成する。 After forming the organic resin layers to be the organic barrier layers 14A and 14B by a known method, O 2 , O 3 or N 2 O gas is turned into plasma to generate oxygen radicals in a high energy state, and the oxygen radicals are converted into the organic resin layer. Irradiate to. The irradiated oxygen radicals combine with the carbon that constitutes the organic resin layer to generate CO 2 , and decompose and vaporize the organic resin layer (sometimes called ashing). By adjusting the plasma energy and oxygen radical irradiation conditions at this time, a concavo-convex structure having a height, a width, and an interval of 20 nm or more and 80 nm or less is independently formed on the surface of the organic barrier layer.
 なお、画素周辺中実部14Baを形成する際に、素子基板の平坦部上にも有機樹脂膜を形成した後、アッシングする場合、平坦部上に存在する第1無機バリア層12の第3表面12Sの微細な凹部(微細な凸部の間)を埋めている有機樹脂をすべて除去する必要はなく、微細な凹部を埋めている有機樹脂を残してもよい。 When the organic resin film is formed on the flat portion of the element substrate when the solid portion 14Ba around the pixel is formed and then ashed, the third surface of the first inorganic barrier layer 12 existing on the flat portion is formed. It is not necessary to remove all the organic resin filling the fine concave portions (between the fine convex portions) of 12S, and the organic resin filling the fine concave portions may be left.
 なお、特許文献1~3等に記載の従来のTFE構造においては、各バリア層の表面は平坦で、表面に形成される凸部の高さおよび幅は、いずれも20nm未満で、典型的には5nm未満であったと考えられる。 In the conventional TFE structure described in Patent Documents 1 to 3, etc., the surface of each barrier layer is flat, and the height and width of the convex portions formed on the surface are typically less than 20 nm. Is believed to have been less than 5 nm.
 本発明の実施形態は、TFE構造を有するOLED表示装置、特にフレキシブルなOLED表示装置およびその製造方法に好適に用いられる。 The embodiment of the present invention is suitably used for an OLED display device having a TFE structure, particularly a flexible OLED display device and a method for manufacturing the same.
 1    :基板(フレキシブル基板)
 2    :回路
 3    :OLED層
 4    :偏光板
 10、10A、10A1、10A2、10B、10B1、10B2   :TFE構造
 12   :第1無機バリア層
 12S  :第1無機バリア層の表面
 12sa :第1サブバリア層
 12sb :第2サブバリア層
 14、14A、14B   :有機バリア層
 14S、14AS、14BS  :有機バリア層の表面
 14Ba  :画素周辺中実部
 16   :第2無機バリア層
 16S  :第2無機バリア層の表面
 30   :引出し配線
 38   :端子
 42   :下部電極
 44   :有機層(有機EL層)
 46   :上部電極
 48   :バンク層
 100、100A1、100A2、100B1、100B2  :OLED表示装置
 P    :パーティクル
1: Substrate (flexible substrate)
2: Circuit 3: OLED layer 4: Polarizing plate 10, 10A, 10A1, 10A2, 10B, 10B1, 10B2: TFE structure 12: First inorganic barrier layer 12S: Surface of first inorganic barrier layer 12sa: First sub-barrier layer 12sb : Second sub-barrier layer 14, 14A, 14B: Organic barrier layer 14S, 14AS, 14BS: Surface of organic barrier layer 14Ba: Solid part around pixel 16: Second inorganic barrier layer 16S: Surface of second inorganic barrier layer 30: Drawer wiring 38: Terminal 42: Lower electrode 44: Organic layer (organic EL layer)
46: Upper electrode 48: Bank layer 100, 100A1, 100A2, 100B1, 100B2: OLED display device P: Particles

Claims (16)

  1.  複数の画素を有する有機EL表示装置であって、
     基板および前記基板に支持された複数の有機EL素子を有する素子基板と、前記複数の有機EL素子を覆う薄膜封止構造とを有し、
     前記薄膜封止構造は、第1無機バリア層と、前記第1無機バリア層上に形成された有機バリア層と、前記有機バリア層上に形成された第2無機バリア層とを有し、
     前記第1無機バリア層は、第1サブバリア層と、前記第1サブバリア層上に形成され、前記有機バリア層に接する第2サブバリア層とを有し、
     前記第1無機バリア層の前記有機バリア層に接する表面は、複数の微細な凸部を有し、前記複数の微細な凸部の高さは20nm以上80nm以下であり、前記複数の微細な凸部の幅は20nm以上80nm以下である、有機EL表示装置。
    An organic EL display device having a plurality of pixels.
    It has a substrate, an element substrate having a plurality of organic EL elements supported by the substrate, and a thin film sealing structure covering the plurality of organic EL elements.
    The thin film sealing structure has a first inorganic barrier layer, an organic barrier layer formed on the first inorganic barrier layer, and a second inorganic barrier layer formed on the organic barrier layer.
    The first inorganic barrier layer has a first sub-barrier layer and a second sub-barrier layer formed on the first sub-barrier layer and in contact with the organic barrier layer.
    The surface of the first inorganic barrier layer in contact with the organic barrier layer has a plurality of fine convex portions, and the height of the plurality of fine convex portions is 20 nm or more and 80 nm or less, and the plurality of fine convex portions. An organic EL display device having a width of 20 nm or more and 80 nm or less.
  2.  前記複数の微細な凸部の間隔は、20nm以上80nm以下である、請求項1に記載の有機EL表示装置。 The organic EL display device according to claim 1, wherein the distance between the plurality of fine convex portions is 20 nm or more and 80 nm or less.
  3.  前記有機バリア層を構成する樹脂材料は前記複数の微細な凸部の隙間に充填されている、請求項1または2に記載の有機EL表示装置。 The organic EL display device according to claim 1 or 2, wherein the resin material constituting the organic barrier layer is filled in the gaps between the plurality of fine convex portions.
  4.  前記第2サブバリア層は、離散的に分布した複数の島状部を有し、前記複数の島状部が前記複数の微細な凸部を形成している、請求項1から3のいずれかに記載の有機EL表示装置。 The second sub-barrier layer has a plurality of discretely distributed island-shaped portions, and the plurality of island-shaped portions form the plurality of fine convex portions, according to any one of claims 1 to 3. The organic EL display device described.
  5.  前記第2サブバリア層は、SiNまたはSiONで形成されている、請求項1から4のいずれかに記載の有機EL表示装置。 The organic EL display device according to any one of claims 1 to 4, wherein the second sub-barrier layer is made of SiN or SiON.
  6.  前記第1サブバリア層の表面粗さは、5nm未満である、請求項1から5のいずれかに記載の有機EL表示装置。 The organic EL display device according to any one of claims 1 to 5, wherein the surface roughness of the first sub-barrier layer is less than 5 nm.
  7.  前記第1サブバリア層は、厚さが10nm以上30nm以下のAl23層である、請求項1から6のいずれかに記載の有機EL表示装置。 The organic EL display device according to any one of claims 1 to 6, wherein the first sub-barrier layer is an Al 2 O 3 layer having a thickness of 10 nm or more and 30 nm or less.
  8.  前記第1サブバリア層は、厚さが200nm以上400nm以下のSiN層またはSiON層である、請求項1から6のいずれかに記載の有機EL表示装置。 The organic EL display device according to any one of claims 1 to 6, wherein the first sub-barrier layer is a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
  9.  前記第2無機バリア層は、厚さが200nm以上400nm以下のSiN層またはSiON層を含む、請求項1から8のいずれかに記載の有機EL表示装置。 The organic EL display device according to any one of claims 1 to 8, wherein the second inorganic barrier layer includes a SiN layer or a SiON layer having a thickness of 200 nm or more and 400 nm or less.
  10.  前記素子基板は、前記複数の画素のそれぞれを規定するバンク層をさらに有し、
     前記有機バリア層は、前記バンク層を覆い、平坦な表面を有している、請求項1から9のいずれかに記載の有機EL表示装置。
    The element substrate further has a bank layer that defines each of the plurality of pixels.
    The organic EL display device according to any one of claims 1 to 9, wherein the organic barrier layer covers the bank layer and has a flat surface.
  11.  前記有機バリア層の厚さは3μm以上10μm以下である、請求項10に記載の有機EL表示装置。 The organic EL display device according to claim 10, wherein the thickness of the organic barrier layer is 3 μm or more and 10 μm or less.
  12.  前記素子基板は、前記複数の画素のそれぞれを規定するバンク層をさらに有し、
     前記バンク層は、前記複数の画素のそれぞれの周囲を包囲する斜面を有し、
     前記有機バリア層は、離散的に分布する複数の中実部を有し、
     前記複数の中実部は、前記第1無機バリア層の、前記斜面上の部分から前記画素内の周辺に至る画素周辺中実部を有する、請求項1から9のいずれかに記載の有機EL表示装置。
    The element substrate further has a bank layer that defines each of the plurality of pixels.
    The bank layer has a slope that surrounds each of the plurality of pixels.
    The organic barrier layer has a plurality of discretely distributed solid parts.
    The organic EL according to any one of claims 1 to 9, wherein the plurality of solid portions have a pixel peripheral solid portion extending from a portion on the slope to the periphery of the pixel of the first inorganic barrier layer. Display device.
  13.  前記有機バリア層の厚さは50nm以上200nm未満である、請求項12に記載の有機EL表示装置。 The organic EL display device according to claim 12, wherein the thickness of the organic barrier layer is 50 nm or more and less than 200 nm.
  14.  前記有機バリア層の前記第2無機バリア層に接する第1表面は、複数の微細な第1凸部を有し、前記複数の微細な第1凸部の高さは20nm以上80nm以下であり、前記複数の微細な第1凸部の幅は20nm以上80nm以下である、請求項1から13のいずれかに記載の有機EL表示装置。 The first surface of the organic barrier layer in contact with the second inorganic barrier layer has a plurality of fine first convex portions, and the height of the plurality of fine first convex portions is 20 nm or more and 80 nm or less. The organic EL display device according to any one of claims 1 to 13, wherein the width of the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  15.  前記複数の微細な第1凸部の間隔は、20nm以上80nm以下である、請求項14に記載の有機EL表示装置。 The organic EL display device according to claim 14, wherein the distance between the plurality of fine first convex portions is 20 nm or more and 80 nm or less.
  16.  前記第2無機バリア層が有する、前記第1表面と接する表面とは逆の第2表面は、複数の微細な第2凸部を有し、前記複数の微細な第2凸部の高さ、幅および間隔は、それぞれ独立に20nm以上80nm以下である、請求項13に記載の有機EL表示装置。 The second surface of the second inorganic barrier layer, which is opposite to the surface in contact with the first surface, has a plurality of fine second convex portions, and the height of the plurality of fine second convex portions. The organic EL display device according to claim 13, wherein the width and the interval are independently 20 nm or more and 80 nm or less.
PCT/JP2019/038017 2019-09-26 2019-09-26 Organic el display device WO2021059459A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP2019/038017 WO2021059459A1 (en) 2019-09-26 2019-09-26 Organic el display device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2019/038017 WO2021059459A1 (en) 2019-09-26 2019-09-26 Organic el display device

Publications (1)

Publication Number Publication Date
WO2021059459A1 true WO2021059459A1 (en) 2021-04-01

Family

ID=75165985

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2019/038017 WO2021059459A1 (en) 2019-09-26 2019-09-26 Organic el display device

Country Status (1)

Country Link
WO (1) WO2021059459A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022011527A1 (en) 2020-07-14 2022-01-20 Intel Corporation Srs configuration and transmission in multi-dci multi-trp and carrier aggregation

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004079291A (en) * 2002-08-13 2004-03-11 Matsushita Electric Works Ltd Organic electroluminescent element
JP2005096108A (en) * 2003-09-22 2005-04-14 Dainippon Printing Co Ltd Antireflection gas barrier substrate
WO2016140130A1 (en) * 2015-03-03 2016-09-09 シャープ株式会社 Electroluminescent device and manufacturing method
JP2018014176A (en) * 2016-07-19 2018-01-25 株式会社ジャパンディスプレイ Display device
JP6385628B1 (en) * 2017-12-25 2018-09-05 堺ディスプレイプロダクト株式会社 Organic EL display device and manufacturing method thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004079291A (en) * 2002-08-13 2004-03-11 Matsushita Electric Works Ltd Organic electroluminescent element
JP2005096108A (en) * 2003-09-22 2005-04-14 Dainippon Printing Co Ltd Antireflection gas barrier substrate
WO2016140130A1 (en) * 2015-03-03 2016-09-09 シャープ株式会社 Electroluminescent device and manufacturing method
JP2018014176A (en) * 2016-07-19 2018-01-25 株式会社ジャパンディスプレイ Display device
JP6385628B1 (en) * 2017-12-25 2018-09-05 堺ディスプレイプロダクト株式会社 Organic EL display device and manufacturing method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2022011527A1 (en) 2020-07-14 2022-01-20 Intel Corporation Srs configuration and transmission in multi-dci multi-trp and carrier aggregation

Similar Documents

Publication Publication Date Title
US20200227674A1 (en) Organic electroluminescent display device and method for producing same
JP6378854B1 (en) Organic EL device and manufacturing method thereof
US11937449B2 (en) Sealing structure and light emitting device
JPWO2018179233A1 (en) Organic EL device and method of manufacturing the same
JP6892931B2 (en) Organic EL display device and its manufacturing method
WO2021059459A1 (en) Organic el display device
JPWO2019202738A1 (en) Organic EL device and its manufacturing method
JP6883668B2 (en) Organic EL display device and its manufacturing method
JP6759287B2 (en) Organic EL device and its manufacturing method
WO2015005638A1 (en) Light extraction substrate for organic light emitting device, fabrication method therefor and organic light emitting device including same
JP6993482B2 (en) Organic EL device and its manufacturing method
JP2020098792A (en) Organic EL device and manufacturing method thereof
JP2006172818A (en) Organic el element, organic el element array, and method of filling and sealing the organic el element
JP6942208B2 (en) Organic EL device and its manufacturing method
WO2017134820A1 (en) Light emitting device and method for manufacturing light emitting device
JP2019114527A (en) Organic el display device and method for manufacturing the same

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19947207

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19947207

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP