Organic EL device and method for manufacturing same

Abstract

This organic EL device (100D) is provided with: a substrate (1); a drive circuit layer (2) having a plurality of TFTs formed on the substrate; interlayer insulating layers (2Pa, 2Pb); an organic EL element layer (3); and a thin film sealing structure (10D) in which the interlayer insulating layer has contact holes (CH1, CH2) in which contact portions (C1, C2) connecting the driving circuit layer and the organic EL element layer are formed, the interlayer insulating layer has a first inorganic protective layer and an organic planarization layer, and the thin film sealing structure has a first inorganic barrier layer, an organic barrier layer, and a second inorganic barrier layer, the outer edge of the film sealing structure intersects with the plurality of lead-out wires and is arranged between the outer edge of the organic planarization layer and the outer edge of the first inorganic protection layer, and the outer edge of the film sealing structure intersects with the outer edge of the organic planarization layer and the outer edge of the first inorganic protection layer in the direct contact part of the first inorganic protection layer and the first inorganic barrier layer on the plurality of lead-out wires. The taper angle of the side surface of the first inorganic barrier layer in the cross-sectional shape parallel to the line width direction of the plurality of lead-out wirings is less than 90 DEG.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is a divisional application with application number 201880091660.1, application date September 23, 2020, and invention name “Organic EL device and manufacturing method thereof”. Technical Field

[0002] The present invention relates to an organic EL device (eg, an organic EL display device and an organic EL lighting device) and a method for manufacturing the same. Background Art

[0003] Organic EL (ElectroLuminescence) display devices have begun to be put into practical use. One feature of an organic EL display device is that a flexible display device can be obtained. An 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) for controlling the current supplied to each OLED. Hereinafter, the organic EL display device is referred to as an OLED display device. As described above, an OLED display device having a switching element such as a TFT for each OLED is called an active matrix OLED display device. In addition, a substrate forming a TFT and an OLED is called an element substrate.

[0004] OLED (especially the organic light-emitting layer and cathode electrode materials) are easily degraded by moisture and prone to uneven display. As a technology to protect OLED from moisture and provide a sealing structure without compromising flexibility, thin film encapsulation (TFE) technology has been developed. Thin film sealing technology is to obtain a film with sufficient water vapor barrier properties by alternately stacking inorganic barrier layers and organic barrier layers. From the perspective of moisture resistance reliability of OLED display devices, the WVTR (Water Vapor Transmission Rate) of the thin film sealing structure is usually required to be 1×10 -4 g / m 2 / day or less.

[0005] The thin film sealing structure used in the OLED display devices currently sold on the market has an organic barrier layer (polymer barrier layer) with a thickness of about 5 μm to about 20 μm. Such a relatively thick organic barrier layer also plays a role in flattening the surface of the element substrate. However, when the organic barrier layer is thick, there is a problem that the bendability of the OLED display device is limited.

[0006] In addition, there is also the problem of low mass productivity. The relatively thick organic barrier layer mentioned above is formed using printing techniques such as inkjet method and microjet method. On the other hand, the inorganic barrier layer is formed in a vacuum atmosphere (for example, below 1 Pa) using thin film forming technology. Since the formation of the organic barrier layer using printing technology is carried out in the air or nitrogen atmosphere, and the formation of the inorganic barrier layer is carried out in a vacuum, the component substrate is taken out of the vacuum chamber and placed in the process of forming the thin film packaging structure, so the mass productivity is low.

[0007] In view of this, as disclosed in Patent Document 1, for example, a film forming apparatus capable of continuously manufacturing an inorganic barrier layer and an organic barrier layer has been developed.

[0008] In addition, the following thin film sealing structure is disclosed in patent document 2: when the first inorganic material layer, the first resin material and the second inorganic material layer are formed in sequence from the element substrate side, the first resin material is unevenly distributed around the convex portion of the first inorganic material layer (the first inorganic material layer covering the convex portion). According to patent document 2, by making the first resin material unevenly distributed around the convex portion that may be fully covered by the first inorganic material layer, moisture and oxygen are inhibited from invading from this part. In addition, the first resin material functions as the base layer of the second inorganic material layer, so that the second inorganic material layer can be properly formed, and the side of the first inorganic material layer can be properly coated with the desired film thickness. The first resin material is formed as follows. The mist-like organic material after heating and vaporization is supplied to the element substrate maintained at a temperature below room temperature, and the organic material condenses and droplets on the substrate. The dropletized organic material moves on the substrate due to capillary phenomenon or surface tension, and is biased to the boundary between the side of the convex portion of the first inorganic material layer and the substrate surface. Afterwards, the first resin material is formed at the boundary by solidifying the organic material. Patent Document 3 also discloses an OLED display device having a similar thin film sealing structure. In addition, Patent Document 4 discloses a film forming device for manufacturing an OLED display device. Prior art literature Patent Literature

[0009] Patent Document 1: Japanese Patent Application Publication No. 2013-186971 Patent Document 2: International Publication No. 2014 / 196137 Patent Document 3: Japanese Patent Application Publication No. 2016-39120 Patent Document 4: Japanese Patent Application Publication No. 2013-64187 Summary of the invention Technical Problems to be Solved by the Invention

[0010] The thin film encapsulation structure described in Patent Document 2 or 3 does not have a thick organic barrier layer, so the bendability of the OLED display device is improved. In addition, since the inorganic barrier layer and the organic barrier layer can be continuously formed, mass productivity is also improved.

[0011] However, according to the research of the present inventors, when the organic barrier layer is formed by the method described in Patent Document 2 or 3, there may be a problem that sufficient moisture resistance reliability cannot be obtained.

[0012] When the organic barrier layer is formed by a printing method such as an inkjet method, the organic barrier layer can be formed only in the active area (or referred to as the "element formation area" or the "display area") on the element substrate, and not in areas other than the active area. Therefore, around the active area (outside), there is an area where the first inorganic material layer and the second inorganic material layer are in direct contact, and the organic barrier layer is completely surrounded by the first inorganic material layer and the second inorganic material layer and isolated from the surroundings.

[0013] In contrast, in the method for forming an organic barrier layer described in Patent Document 2 or 3, a resin (organic material) is supplied to the entire surface of the element substrate, and the surface tension of the liquid resin is used to bias the resin toward the boundary between the side of the convex portion on the surface of the element substrate and the surface of the substrate. Therefore, an organic barrier layer is also formed in an area outside the active area (also referred to as a "peripheral area"), that is, in a terminal area where a plurality of terminals are configured, and in a lead-out wiring area where lead-out wiring from the active area to the terminal area is formed. Specifically, for example, resin is unevenly present at the boundary between the side of the lead-out wiring and the terminal and the surface of the substrate. In this way, the end of the portion of the organic barrier layer formed along the lead-out wiring is not surrounded by the first inorganic barrier layer and the second inorganic barrier layer and is exposed to the atmosphere (peripheral atmosphere).

[0014] The organic barrier layer has a lower barrier property against water vapor than the inorganic barrier layer. Therefore, the organic barrier layer formed along the lead wiring serves as a path for introducing water vapor in the atmosphere into the active region.

[0015] Here, the problem of the thin film sealing structure of the organic EL display device is described here, but the thin film sealing structure is not limited to the organic EL display device, and is also used in other organic EL devices such as an organic EL lighting device.

[0016] In addition, the lower electrode or organic layer of the OLED (also called an organic EL layer, including at least an organic light-emitting layer) requires high flatness. When the flatness is low, for example, the luminous efficiency of the OLED decreases. For example, if the flatness of the lower electrode or organic layer of the OLED is low, even if a micro-resonator structure is used, there is a problem that its effect cannot be fully manifested.

[0017] The present invention is made to solve at least one of the above problems. One embodiment of the present invention aims to provide an organic EL device with a thin film encapsulation structure and a manufacturing method thereof, wherein the thin film encapsulation structure improves mass production and moisture resistance reliability and has a relatively thin organic barrier layer. Another embodiment of the present invention aims to provide an organic EL device capable of improving luminous efficiency and a manufacturing method thereof. Technical solutions for solving technical problems

[0018] An organic EL device according to an embodiment of the present invention includes: a substrate; a driving circuit layer, which has: a plurality of TFTs formed on the substrate, a plurality of gate bus lines and a plurality of source bus lines respectively connected to any one of the plurality of TFTs, a plurality of terminals, and a plurality of lead wirings connecting the plurality of terminals to any one of the plurality of gate bus lines or the plurality of source bus lines; an interlayer insulating layer, which is formed on the driving circuit layer; an organic EL element layer, which is formed on the interlayer insulating layer and has a plurality of organic EL elements respectively connected to any one of the plurality of TFTs; and a thin film sealing structure, which is formed in a manner covering the organic EL element layer, the interlayer insulating layer having a contact hole, a contact portion connecting the driving circuit layer and the organic EL element layer being formed in the contact hole, the interlayer insulating layer having: a first inorganic protective layer, which at least exposes the plurality of terminals; and an organic planarizing layer, which is formed on the first inorganic protective layer, the thin film sealing structure The film sealing structure comprises: a first inorganic barrier layer, an organic barrier layer in contact with an upper surface of the first inorganic barrier layer, and a second inorganic barrier layer in contact with an upper surface of the organic barrier layer, wherein the organic barrier layer is formed in a region surrounded by an inorganic barrier layer connecting portion in which the first inorganic barrier layer and the second inorganic barrier layer are in direct contact, wherein the organic planarizing layer is formed in a region in which the first inorganic protective layer is formed when viewed from a normal direction of the substrate, wherein the plurality of organic EL elements are arranged in a region in which the organic planarizing layer is formed, wherein an outer edge of the thin film sealing structure intersects with the plurality of lead wirings and exists between an outer edge of the organic planarizing layer and an outer edge of the first inorganic protective layer, and wherein a taper angle of a side surface of the first inorganic barrier layer in a cross-sectional shape parallel to a line width direction of the plurality of lead wirings in a portion in which the first inorganic protective layer and the first inorganic barrier layer are in direct contact on the plurality of lead wirings is less than 90°.

[0019] The organic EL device includes a plurality of pixels, each of the plurality of pixels includes one of the plurality of organic EL elements, and the contact portion is formed inside each of the plurality of pixels.

[0020] In one embodiment, the plurality of organic EL elements include a lower electrode, an organic layer, and an upper electrode facing the lower electrode with the organic layer interposed therebetween, and the contact portion is formed of a material different from that of the lower electrode.

[0021] In one embodiment, the arithmetic mean roughness Ra of the surface of the organic planarization layer is 50 nm or less.

[0022] In one embodiment, the interlayer insulating layer further includes: a second inorganic protective layer formed on the organic planarizing layer, and an arithmetic mean roughness Ra of a surface of the second inorganic protective layer is 50 nm or less.

[0023] In one embodiment, the taper angle of the side surface of the first inorganic barrier layer is less than 70°.

[0024] In one embodiment, the organic planarization layer is formed of polyimide.

[0025] A manufacturing method according to one embodiment of the present invention is a manufacturing method of the organic EL device of the above-mentioned embodiment, which includes: step A, which forms the driving circuit layer on the substrate; step B, which forms an interlayer insulating film with contact holes on the driving circuit layer; step C, which forms a contact film with conductivity covering the interlayer insulating film; and step D, which obtains the interlayer insulating layer and the contact portion by performing chemical mechanical polishing on the surface of the contact film and the surface of the interlayer insulating film.

[0026] In one embodiment, the step C includes: forming a titanium film by sputtering; and forming a copper film on the titanium film by plating.

[0027] In one embodiment, the process B includes: a process of forming a first inorganic protective film on the driving circuit layer; and a process of forming an organic planarization film on the first inorganic protective film, and the manufacturing method also includes: after the process D, a process E of heating the interlayer insulating layer to a temperature above 100°C; after the above process E, a process F of forming an organic layer included in the above organic EL element on the above interlayer insulating layer.

[0028] In one embodiment, the step D includes a step of performing chemical mechanical polishing on the surface of the organic planarization film.

[0029] In one embodiment, the process B includes: a process of forming a first inorganic protective film on the driving circuit layer; a process of forming an organic planarization film on the first inorganic protective film; a process of forming a second inorganic protective film on the organic planarization film; a process of forming a contact hole penetrating the first inorganic protective film, the organic planarization film and the second inorganic protective film; the process D includes a process of performing chemical mechanical polishing on the surface of the second inorganic protective film. Beneficial Effects

[0030] According to one embodiment of the present invention, an organic EL device having a thin film sealing structure with improved moisture resistance reliability and a method for manufacturing the same are provided, wherein the thin film sealing structure has a thin organic barrier layer. According to another embodiment of the present invention, an organic EL device capable of improving luminous efficiency and a method for manufacturing the same are provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 (a) is a schematic partial cross-sectional view of an active region of an OLED display device 100 according to an embodiment of the present invention, Figure 1 (b) is a partial cross-sectional view of the TFE structure 10 formed on the OLED 3 . Figure 2 is a top view schematically showing an OLED display device 100A according to an embodiment of the present invention. Figure 3 (a) and (b) are schematic cross-sectional views of the OLED display device 100A, and (a) is a cross-sectional view taken along Figure 2 The cross-sectional view along the line 3A-3A' in FIG. 1 and (b) along the line 3A-3A' in FIG. Figure 2 (c) is a cross-sectional view taken along line 3B-3B' of FIG. 1 , and (c) is a cross-sectional view showing a taper angle θ of the side surface of each layer. Figure 4 (a) to (d) are schematic cross-sectional views of the OLED display device 100A, and (a) is a cross-sectional view taken along Figure 2 The cross-sectional view along the line 4A-4A' in FIG. 4A-4A', (b) is a cross-sectional view along the line 4A-4A' in FIG. Figure 2 The cross-sectional view along the line 4B-4B' in (c) is Figure 2 The cross-sectional view along the 4C-4C' line in (d) is Figure 2 Cross-sectional view along line 44D-4D'. Figure 5 (a) and (b) are the OLED display devices 100B1 and 100B2 of the comparative example. Figure 4 (b) corresponds to a schematic cross-sectional view. Figure 6 is a schematic top view of an OLED display device 100C according to a comparative example. Figure 7(a) and (b) are schematic cross-sectional views of the OLED display device 100C, and (a) is a cross-sectional view taken along Figure 6 7A-7A' line cross-sectional view, (b) is along the Figure 6 Cross-sectional view along line 7B-7B'. Figure 8 (a) to (c) are schematic cross-sectional views of the OLED display device 100C, and (a) is a cross-sectional view taken along Figure 6 8A-8A' line in FIG. 8A-8A' line, (b) is a cross-sectional view along the line Figure 6 The cross-sectional view along the line 8B-8B' in FIG. 8B-8B', (c) is a cross-sectional view along the line 8B-8B' in FIG. Figure 6 Cross-sectional view along line 8C-8C'. Fig. 9 (a) and (b) are schematic cross-sectional views each showing an example of a TFT that can be included in the OLED display device of the embodiment. Fig.10 (a) to (c) are schematic cross-sectional views of another OLED display device according to an embodiment of the present invention, respectively. Figure 4 (b) to (d) correspond to. Fig.11 (a) and (b) are schematic cross-sectional views of still another OLED display device 100D according to the embodiment. Fig.12 (a) to (c) are schematic cross-sectional views for explaining a method for manufacturing the OLED display device 100D. Fig.13 (a) and (b) are schematic cross-sectional views of still another OLED display device 100E according to an embodiment. Fig.14 (a) to (c) are schematic cross-sectional views for explaining a method for manufacturing the OLED display device 100E. Fig.15 (a) and (b) are diagrams schematically showing the structure of the film-forming device 200, (a) shows the state of the film-forming device 200 in the process of condensing the photocurable resin on the first inorganic barrier layer, and (b) shows the state of the film-forming device 200 in the process of curing the photocurable resin. DETAILED DESCRIPTION

[0032] Hereinafter, an OLED display device and a manufacturing method thereof according to an embodiment of the present invention will be described with reference to the accompanying drawings. Hereinafter, an OLED display device having a flexible substrate is exemplified, but the embodiment of the present invention is not limited to an organic EL display device, and may also be other organic EL devices such as an organic EL lighting device, and is not limited to the embodiment exemplified below.

[0033] First, refer to Figure 1(a) and (b) illustrate a basic configuration of the OLED display device 100 according to an embodiment of the present invention. Figure 1 (a) is a schematic partial cross-sectional view of an active region of an OLED display device 100 according to an embodiment of the present invention, Figure 1 (b) is a partial cross-sectional view of the TFE structure 10 formed on the OLED 3.

[0034] The OLED display device 100 has a plurality of pixels, and each pixel has at least one organic EL element (OLED). Here, for simplicity, a structure corresponding to one OLED is described.

[0035] like Figure 1 As shown in (a) of FIG. 1 , the OLED display device 100 includes: a flexible substrate (hereinafter, sometimes simply referred to as a "substrate") 1, a circuit (also referred to as a "driving circuit" or a "backplane circuit") including TFTs formed on the substrate 1, an inorganic protective layer (first inorganic protective layer) 2Pa formed on the circuit 2, an organic planarization layer 2Pb formed on the inorganic protective layer 2Pa, an OLED 3 formed on the organic planarization layer 2Pb, and a TFE structure 10 formed on the OLED 3. Hereinafter, the substrate 1, the circuit 2 formed on the substrate 1, the inorganic protective layer 2Pa, the organic planarization layer 2Pb, and the OLED 3 will be referred to as an element substrate 20. That is, the substrate 1 and the structural elements arranged on the side of the substrate 1 closer to the substrate 1 than the TFE structure 10 are collectively referred to as an element substrate.

[0036] OLED 3 is, for example, a top emission type. The uppermost portion of OLED 3 is, for example, an upper electrode or a cap layer (refractive index adjustment layer). The layer in which a plurality of OLEDs 3 are arranged may be referred to as OLED layer 3. An optional polarizing plate 4 is disposed on the TFE structure 10. In addition, the circuit 2 and the OLED layer 3 may also share some components. In addition, for example, a layer responsible for the touch panel function may also be disposed between the TFE structure 10 and the polarizing plate 4. That is, the OLED display device 100 may be changed into a display device with an on-cell touch panel.

[0037] The substrate 1 is, for example, a polyimide film having a thickness of 15 μm. The circuit 2 including the TFT has a thickness of, for example, 4 μm. The inorganic protective layer 2Pa is, for example, SiN x Layer (500 nm) / SiO2 layer (100 nm) (upper layer / lower layer). In addition, the inorganic protective layer 2Pa may also be, for example, SiO2 layer / SiN x The inorganic protective layer 2Pa may be a SiN layer or a SiO2 layer. xThe organic planarization layer 2Pb is, for example, an acrylic resin layer, an epoxy resin layer, or a polyimide layer with a thickness of 4 μm. The organic planarization layer 2Pb can be formed using a photosensitive resin or a resin that is not photosensitive. The thickness of the OLED 3 is, for example, 1 μm. The thickness of the TFE structure 10 is, for example, less than 2.5 μm.

[0038] Figure 1 (b) is a partial cross-sectional view of the TFE structure 10 formed on the OLED 3. A first inorganic barrier layer (eg, SiN x An organic barrier layer (such as an acrylic resin layer) 14 is formed on the first inorganic barrier layer 12, and a second inorganic barrier layer (such as SiN x Layer)16.

[0039] For example, the first inorganic barrier layer 12 is SiN with a thickness of 1.5 μm. x The second inorganic barrier layer 16 is, for example, SiN with a thickness of 800 nm. x The organic barrier layer 14 is, for example, a propylene resin layer with a thickness of less than 100 nm. The thickness of the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are independently 200 nm to 1500 nm, and the thickness of the organic barrier layer 14 is 50 nm to less than 200 nm. The thickness of the TFE structure 10 is preferably 400 nm to less than 3 μm, more preferably 400 nm to 2.5 μm.

[0040] The TFE structure 10 is formed to protect the active region of the OLED display device 100 (refer to Figure 2 As described above, at least in the active region R1, there are a first inorganic barrier layer 12, an organic barrier layer 14, and a second inorganic barrier layer 16 in order from the side close to the OLED 3. In addition, the organic barrier layer 14 does not exist as a film covering the entire active region, but has an opening. The portion of the organic barrier layer 14 where the organic film actually exists except for the opening is called a "solid portion". For example, the organic barrier layer 14 can be formed by the method described in Patent Documents 1 or 2, or by using the film forming device 200 described later.

[0041] In addition, in the "opening" (also referred to as "non-solid part"), it is not necessary to be surrounded by a solid part, including a cutout, etc., and in the opening, the first inorganic barrier layer 12 is in direct contact with the second inorganic barrier layer 16. Hereinafter, the portion where the first inorganic barrier layer 12 is in direct contact with the second inorganic barrier layer 16 is referred to as an "inorganic barrier layer connecting portion".

[0042] Below, refer to Figures 2 to 3The structure of the OLED display device 100A and a method for manufacturing the same according to an embodiment of the present invention are described.

[0043] Figure 2 Schematically shows a top view of an OLED display device 100A according to an embodiment of the present invention. Figure 3 (a) to (c) and Figure 4 (a) to (d) illustrate the cross-sectional structure of the OLED display device 100A. Figure 3 (a) and (b) are schematic cross-sectional views of an OLED display device 100A, and Figure 3 (a) is along Figure 2 The cross-sectional view of line 3A-3A' in FIG. Figure 3 (b) is along Figure 2 Cross-sectional view along line 3B-3B'. Figure 3 (c) is a cross-sectional view showing the taper angle θ of the side surface of each layer. Figure 4 (a) to (d) are schematic cross-sectional views of an OLED display device 100A, and Figure 4 (a) is along Figure 2 The cross-sectional view of the line 4A-4A' in FIG. Figure 4 (b) is along Figure 2 The cross-sectional view of the line 4B-4B' in FIG. Figure 4 (c) is along Figure 2 The cross-sectional view of the 4C-4C' line in Figure 4 (d) is along Figure 2 Cross-sectional view along line 4D-4D'.

[0044] First, refer to Figure 2 The circuit 2 formed on the substrate 1 has a plurality of TFTs (not shown), and a plurality of gate buses (not shown) and a plurality of source buses (not shown) respectively connected to any one 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 one of the plurality of TFTs of the circuit 2. The OLED 3 may also be a known OLED.

[0045] The circuit 2 further comprises: a plurality of terminals 34, which are arranged in an active area ( Figure 2 The circuit 2 includes a plurality of TFTs, a plurality of gate buses, a plurality of source buses, a plurality of lead wirings 32, and a plurality of terminals 34, and the entire circuit 2 is referred to as a drive circuit layer 2. In addition, within the drive circuit layer 2, the portion formed within the active region R1 is marked as a drive circuit layer 2A.

[0046] In addition, Figure 2 In the figure, only the lead wiring 32 and / or the terminal 34 are shown as the components of the driving circuit layer 2, but the driving circuit layer 2 has not only a conductive layer including the lead wiring 32 and the terminal 34, but also one or more conductive layers, one or more insulating layers, and one or more semiconductor layers. The structure of the conductive layer, insulating layer, and semiconductor layer included in the driving circuit layer 2 can be described later, for example. Fig. 9 Alternatively, an insulating film (primer film) may be formed on the substrate 1 as a base film of the driving circuit layer 2 .

[0047] When viewed from the normal direction of the substrate 1, an organic planarization layer 2Pb is formed in the region where the inorganic protective layer 2Pa is formed, and an active region R1 (2A, 3) is arranged in the region where the organic planarization layer 2Pb is formed. The outer edge of the TFE structure 10 intersects with the plurality of lead wires 32 and exists between the outer edge of the organic planarization layer 2Pb and the outer edge of the inorganic protective layer 2Pa. Therefore, the organic planarization layer 2Pb and the OLED layer 3 are surrounded by the connection portion where the inorganic protective layer 2Pa and the first inorganic barrier layer 12 are in direct contact (see Figure 3 (b) and Figure 4 (b)). The inorganic protective layer 2Pa is formed, for example, by a plasma CVD method using a mask (e.g., a metal mask) in such a manner that at least a plurality of terminals 34 are exposed. Alternatively, an inorganic protective film may be first formed by a plasma CVD method in such a manner as to cover the terminals 34, and then patterned by a photolithography process (including a dry etching process) to form an opening that exposes the terminals 34, thereby obtaining the inorganic protective layer 2Pa. In addition, as described later, when a second inorganic protective layer 2Pa2 is formed on the organic planarization layer 2Pb (see Fig.13 (a)), it is preferred that the inorganic protective film 2Pa (first inorganic protective film 2Pa1), the organic planarization film 2Pb, and the second inorganic protective layer 2Pa2 are patterned together including the formation of contact holes (see Fig.14 (b)).

[0048] The inorganic protective layer 2Pa protects the driving circuit layer 2. The organic planarizing layer 2Pb planarizes the surface of the substrate on which the OLED layer 3 is formed. Like the organic barrier layer 14, the organic planarizing layer 2Pb has a lower water vapor barrier property than the inorganic protective layer 2Pa and the inorganic barrier layers 12 and 16. Figure 6 to Figure 8If a portion of the organic planarizing layer 2Pbc is exposed to the atmosphere (surrounding atmosphere), as in the organic planarizing layer 2Pbc of the OLED display device 100C of the comparative example shown in FIG. 1 , moisture is absorbed from the organic planarizing layer 2Pbc. As a result, the organic planarizing layer 2Pbc becomes a path for guiding water vapor in the atmosphere into the active region R1. As described above, in the OLED display device 100 of the embodiment, the organic planarizing layer 2Pb is surrounded by the connection portion where the inorganic protective layer 2Pa and the first inorganic barrier layer 12 are in direct contact, thereby preventing moisture from being introduced into the active region R1 from the organic planarizing layer 2Pb.

[0049] The organic planarization layer 2Pb is formed of, for example, a photosensitive resin. The organic planarization layer 2Pb is formed using various coating methods or printing methods. In addition, if it has photosensitivity, it is easy to form the organic planarization layer 2Pb only in a predetermined area in a photolithography process. For example, after applying a photosensitive resin to almost the entire surface of the element substrate, by exposing and developing the photosensitive resin, it is possible to form the organic planarization layer 2Pb only in a predetermined area (for example, see FIG. 1 ) except for the peripheral portion of the element substrate. Fig.11 (b)) to form an organic resin film. When a photosensitive resin is used, a contact hole can be formed by a photolithography process. The photosensitive resin can be either positive or negative. Acrylic resin, epoxy resin, and polyimide resin with photosensitivity can be appropriately used. Of course, if a photoresist is used in addition, a resin without photosensitivity can also be used to form the organic planarization layer 2Pb.

[0050] Organic resins easily contain moisture. On the other hand, as described above, OLEDs (especially organic light-emitting layers and cathode electrode materials) are easily degraded by moisture. Therefore, before forming the OLED layer 3 on the organic planarization layer 2Pb, in order to remove the moisture contained in the organic planarization layer 2Pb, it is preferably heated (dried). The heating temperature is preferably, for example, above 100°C (for example, for more than 1 hour), and more preferably above 250°C (for example, for more than 15 minutes). The atmosphere may be at atmospheric pressure. If heating is performed under a reduced pressure atmosphere, the heating time can be shortened. In order to prevent thermal degradation during the heating (baking) process, a resin material with high heat resistance is preferred, such as polyimide.

[0051] In addition, after the organic planarization layer 2Pb is formed, before the OLED layer 3 is formed, the element substrate is sometimes stored or transported. That is, after the element substrate on which the drive circuit layer 2, the inorganic protective layer 2Pa and the organic planarization layer 2Pb are formed is produced, until the OLED layer 3 is formed, sometimes there is a time vacancy (for example, storage for more than one day to several days), or it is moved to another factory. During this period, as a method to prevent the surface of the organic planarization layer 2Pb from being contaminated or to prevent dust from adhering during movement, for example, a positive photoresist film covering the organic planarization layer 2Pb can be formed. The photoresist film is preferably formed by pre-baking (volatilization removal of the solvent: for example, heating for about 5 minutes to about 30 minutes in a temperature range of about 90°C or more and about 110°C or less) after applying a photoresist solution. After storage or movement, before the OLED layer 3 is formed, a clean surface of the organic planarization layer 2Pb can be obtained by removing the photoresist film. The removal of the photoresist film is preferably performed by developing the entire surface of the photoresist film without performing a normal post-bake, or by stripping it with a stripping solution without performing a full-surface exposure after pre-bake. As a material for forming a positive photoresist film, for example, a positive photoresist named OFPR-800 manufactured by Tokyo Ohka Co., Ltd. can be appropriately used.

[0052] In addition, as referenced Fig.11 As described later in (a), a bank layer is formed during the process of forming the OLED layer 3. After the lower electrode is formed, the bank layer is formed before the organic layer (organic EL layer) is formed. The bank layer is formed of an organic resin (such as polyimide), and therefore easily contains moisture and is in contact with the organic layer. Therefore, it is preferred to heat in order to remove the moisture from the bank layer. Here, after the organic planarization layer 2Pb is formed, the lower electrode is formed, and the channel layer is formed, a positive photoresist film for protecting the surface of the element substrate may also be formed as described above. After necessary storage and / or transportation, the photoresist film is removed as described above, and immediately before the organic layer is formed, the moisture contained in the organic planarization layer 2Pb and the bank layer is removed by heating. In this way, both the heating process for removing the moisture contained in the organic planarization layer 2Pb and the heating process for removing the moisture contained in the bank layer can be used. Of course, as described above, after the organic planarizing layer 2Pb is protected by a positive photoresist film and the positive photoresist film is removed, a heating process is performed to remove the moisture contained in the organic planarizing layer 2Pb. Thereafter, after the lower electrode and the embankment layer are formed and before the organic layer is formed, a heating process may also be performed to remove the moisture contained in the embankment layer.

[0053] Next, refer to Figure 3 (a) to (c) and Figure 4(a) to (d) of FIG. 1 further illustrate the cross-sectional structure of the OLED display device 100A in detail.

[0054] like Figure 3 (a), (b) and Figure 4 As shown in (a) and (b), the TFE structure 10A comprises: a first inorganic barrier layer 12 formed on the OLED 3, an organic barrier layer 14, and a second inorganic barrier layer 16 connected to the organic barrier layer 14. The first inorganic barrier layer 12 and the second inorganic barrier layer 16 are, for example, SiN x A layer is formed and selectively formed only on a prescribed area to cover the active region R1 by a plasma CVD method using a mask.

[0055] For example, the organic barrier layer 14 can be formed by the method described in Patent Document 2 or 3. For example, in a chamber, a vapor or mist of an organic material (e.g., an acrylic monomer) is supplied to an element substrate maintained at a temperature below room temperature, and condensed on the element substrate, and unevenly distributed on the boundary between the side of the convex portion and the flat portion of the first inorganic barrier layer 12 by the capillary phenomenon or surface tension of the organic material that has become liquid. Thereafter, by irradiating the organic material with, for example, ultraviolet rays, a solid portion of the organic barrier layer (e.g., an acrylic resin layer) 14 is formed on the boundary around the convex portion. The organic barrier layer 14 formed by this method has substantially no solid portion on the flat portion. Regarding the method for forming the organic barrier layer, for reference, the disclosures of Patent Documents 2 and 3 are cited in this specification.

[0056] The organic barrier layer 14 may also be formed by adjusting the initial thickness (e.g., less than 100 nm) of the resin layer formed using the film forming apparatus 200 and / or ashing the temporarily formed resin layer. As described in detail later, for example, ashing may be performed by plasma ashing using at least one gas selected from N2O, O2, and O3.

[0057] Figure 3 (a) is along Figure 2 3A-3A' line in FIG. 3A-3A' line, and shows a portion including particles P. Particles P are fine waste generated in the manufacturing process of the OLED display device, such as fine glass fragments, metal particles, and organic particles. If a mask evaporation method is used, particles are particularly likely to be generated.

[0058] like Figure 3As shown in (a), the organic barrier layer (solid part) 14 can be formed only around the microparticles P. This is because the acrylic monomer applied after the first inorganic barrier layer 12 is formed is condensed and unevenly distributed around the surface (taper angle θ is 90° or more) of the first inorganic barrier layer 12a on the microparticles P. The flat part of the first inorganic barrier layer 12 becomes the opening (non-solid part) of the organic barrier layer 14.

[0059] If there are fine particles (for example, having a diameter of about 1 μm or more) P, cracks (defects) 12c are formed in the first inorganic barrier layer 12. This is considered to be due to the SiN grown from the surface of the fine particles P. x The layer 12a is formed by the SiN layer grown from the flat part of the surface of the OLED 3. x If such cracks 12c exist, the barrier properties of the TFE structure 10A will be reduced.

[0060] In the TFE structure 10A of the OLED display device 100A, as shown in FIG. Figure 3 As shown in (a), the organic barrier layer 14 is formed in a manner that fills the cracks 12c of the first inorganic barrier layer 12, and the surface of the organic barrier layer 14 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 of the OLED 3. Therefore, no defects are formed on the first inorganic barrier layer 12 on the particles P and the second inorganic barrier layer 16 formed on the organic barrier layer 14, and a dense film is formed. In this way, the barrier property of the TFE structure 10A can be maintained even if the particles P exist, through the organic barrier layer 14.

[0061] Next, refer to Figure 3 (b) and Figure 4 (a) to (d) illustrate the cross-sectional structure of the lead wiring 32 and the terminal 34.

[0062] like Figure 3As shown in (b), a lead wiring 32 and a terminal 34 are integrally formed on the substrate 1, and an inorganic protective layer 2Pa is formed on the lead wiring 32 to expose the terminal 34. An organic planarization layer 2Pb is formed on the inorganic protective layer 2Pa, and an OLED layer 3 is formed on the organic planarization layer 2Pb. The TFE structure 10A is formed in a manner to cover the OLED layer 3 and the organic planarization layer 2Pb, and the OLED layer 3 and the organic planarization layer 2Pb are surrounded by the connection portion where the inorganic protective layer 2Pa is in direct contact with the first inorganic barrier layer 12. In addition, the organic barrier layer (solid portion) 14 between the first inorganic barrier layer 12 and the second inorganic barrier layer 16 of the TFE structure 10A is only formed around the convex portion such as the particles, and is therefore not shown here. The organic barrier layer (solid portion) 14 is surrounded by the inorganic barrier layer connection portion where the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact.

[0063] like Figure 4 As shown in (a), in the area close to the active area R1 ( Figure 2 In the cross section along line 4A- 4A′ in FIG. 1 , an inorganic protective layer 2Pa, an organic planarizing layer 2Pb, and a TFE structure 10A are formed on the lead wiring 32.

[0064] like Figure 4 As shown in (b), along Figure 2 In the cross section of the line 4B-4B' in FIG. 4B, the inorganic protective layer 2Pa is in direct contact with the first inorganic barrier layer 12, and the organic planarization layer 2Pb is surrounded by the connection portion in direct contact with the first inorganic barrier layer 12 (refer to Figure 2 , Figure 3 (b)).

[0065] like Figure 4 As shown in (c) , in the region close to the terminal 34 , only the inorganic protective layer 2Pa is formed on the lead wiring 32 .

[0066] like Figure 4 As shown in (d), the terminal 34 is also exposed from the inorganic protective layer 2Pa and is used for electrical connection with an external circuit (for example, FPC (Flexible Printed Circuits)).

[0067] Due to the inclusion Figure 4 The area shown in (b) to (d) of FIG. 1 is not covered by the organic planarizing layer 2Pb, so that the organic barrier layer (solid portion) can be formed in the process of forming the organic barrier layer 14 of the TFE structure 10A. For example, if the side surface of the cross-sectional shape of the lead wiring 32 parallel to the line width direction has a taper angle θ of 90° or more, the organic barrier layer can be formed along the side surface of the lead wiring 32. However, if Figure 4As shown in (b) to (d) of the embodiment, in the OLED display device 100A, at least in these regions, the taper angle θ of the side of the cross-sectional shape of the lead wiring 32 and the terminal 34 is set to be less than 90°, and the photocurable resin does not exist unevenly. Therefore, the organic barrier layer (solid portion) is not formed along the side of the lead wiring 32 and the terminal 34.

[0068] Here, refer to Figure 3 (c) illustrates the taper angle θ of the side surface of each layer. Figure 3 (c) is a cross-sectional view showing the taper angle θ of the side surface of each layer, for example Figure 4 The cross-sectional view shown in (b) corresponds to the cross-sectional view shown in (b). Figure 3 As shown in (c), the taper angle θ of the side surface in the cross-sectional shape parallel to the width direction of the lead wiring 32 is represented by θ(32), and the taper angle θ of the side surface of other layers is similarly represented by θ (reference number of the component).

[0069] In this way, the taper angles θ of the inorganic protective layer 2Pa formed on the lead wiring 32, the side surface of the first inorganic barrier layer 12 of the TFE structure 10A formed on the inorganic protective layer 2Pa, and the side surface of the second inorganic barrier layer 16 satisfy the relationship of θ(32)≥θ(2Pa)≥θ(12)≥θ(16). Therefore, if the taper angle θ(32) of the side surface of the lead wiring 32 is less than 90°, the taper angle θ(2Pa) of the side surface of the inorganic protective layer 2Pa and the taper angle θ(12) of the side surface of the first inorganic barrier layer 12 are also less than 90°.

[0070] If the taper angle θ of the side surface is 90° or more, in the method for forming the organic barrier layer described in Patent Documents 2 or 3, vapor or mist of an organic material (e.g., an acrylic monomer) condenses along the boundary (forming an angle of 90° or less) between the side surface and the flat surface to form an organic barrier layer (solid portion). In this way, for example, the organic barrier layer (solid portion) formed along the lead wiring becomes a path for introducing water vapor in the atmosphere into the active region.

[0071] For example, Figure 5 The OLED display device 100B1 of the comparative example (a) is Figure 4As shown in the schematic cross-sectional view corresponding to (b), if the taper angle θ(32B1) of the side of the lead wiring 32B1 and the taper angle θ(12B1) of the side of the first inorganic barrier layer 12B1 are 90° or more, an organic barrier layer (solid portion) 14B1 is formed between the first inorganic barrier layer 12B1 and the second inorganic barrier layer 16B1 along the side of the first inorganic barrier layer 12B1 of the TFE structure 10B1. In addition, the OLED display device 100B1 may also omit the inorganic protective layer 2Pa in the OLED display device 100 of the embodiment, and change the taper angle θ(32) of the side of the lead wiring 32 and the taper angle θ(12) of the side of the first inorganic barrier layer 12 to 90° or more.

[0072] In addition, if Figure 5 The OLED display device 100B2 of the comparative example (b) is Figure 4 As shown in the schematic cross-sectional view corresponding to (b), if the taper angles θ(32B2), θ(2PaB2) and θ(12B2) of the side surfaces of the lead wiring 32B2, the inorganic protective layer 2PaB2 and the first inorganic barrier layer 12B2 are 90° or more, an organic barrier layer (solid portion) 14B2 is formed between the first inorganic barrier layer 12B2 and the second inorganic barrier layer 16B2 along the side surface of the first inorganic barrier layer 12B2 of the TFE structure 10B2. In addition, the OLED display device 100B2 can change the side taper angle θ(32) of the lead wiring 32 and the side taper angle θ(12) of the first inorganic barrier layer 12 in the OLED display device 100A of the embodiment to 90° or more.

[0073] The OLED display device 100B2 is different from the OLED display device 100B1. Since the OLED display device 100B2 has the inorganic protective layer 2PaB2, the side taper angle θ(12B2) of the first inorganic barrier layer 12B2 is easily smaller than the side taper angle θ(12B1) of the first inorganic barrier layer 12B1 of the OLED display device 100B1.

[0074] Figure 4 In the OLED display device 100A of the embodiment of the present invention shown in (b) to (d), the taper angles θ(32), θ(2Pa) and θ(12) of the side surfaces of the lead wiring 32, the inorganic protective layer 2Pa and the first inorganic barrier layer 12 are all less than 90°, and the organic barrier layer 14 is not formed along these sides. Therefore, moisture in the atmosphere does not reach the active region R1 through the organic barrier layer (solid portion) 14, thereby achieving excellent moisture resistance reliability. Although an example in which the taper angles θ(32), θ(2Pa) and θ(12) are all less than 90° is shown here, it is not limited to this. As long as the taper angle θ(12) of the side surface of at least the first inorganic barrier layer 12 constituting the surface directly below the organic barrier layer 14 is less than 90°, an organic barrier layer 14 is formed. Figure 4 The stacked structure shown in (b) (the portion where the inorganic protective layer 2Pa is in direct contact with the first inorganic barrier layer 12 (the organic planarization layer 2Pb is not present) and the portion where the first inorganic barrier layer 12 is in direct contact with the second inorganic barrier layer 16 (the organic barrier layer 14 is not present)) can suppress and prevent moisture in the atmosphere from entering through the organic planarization layer 2Pb or the organic barrier layer 14 in the active region R1. In addition, since the inorganic protective layer 2Pa is present, the taper angle θ(12) of the first inorganic barrier layer 12 can be reduced. Therefore, even if the taper angle θ(32) of the lead wiring 32 is relatively large (for example, 90°), the taper angle θ(12) of the first inorganic barrier layer 12 can be made smaller than 90°. That is, since the taper angle θ(32) of the lead wiring 32 can be made 90° or close to 90°, the advantage of reducing the L / S of the lead wiring 32 can be obtained.

[0075] In addition, when the taper angle θ of the side surface is within the range of 70° or more and less than 90°, an organic barrier layer (solid portion) 14 is sometimes formed along the side surface. Of course, if an ashing treatment is performed, the resin that is unevenly present along the inclined side surface can be removed, but the time required for the ashing treatment becomes longer. For example, even after the resin formed on the flat surface is removed, a long ashing treatment is required. Alternatively, the organic barrier layer (solid portion) formed around the particles P is excessively ashed (removed), and as a result, there is a problem that the effect of forming the organic barrier layer cannot be fully exerted. In order to suppress and prevent this problem, the taper angle θ(12) of the first inorganic barrier layer 12 is preferably set to less than 70°, and more preferably less than 60°.

[0076] Next, refer to Figures 6 to 8 , describing the structure of an OLED display device 100C of a comparative example. Figure 6 is a schematic top view of the OLED display device 100C. Figure 7 (a) and (b) are schematic cross-sectional views of an OLED display device 100C, and Figure 7 (a) is along Figure 6 The cross-sectional view of line 7A-7A' in FIG. Figure 7 (b) is along Figure 6 Cross-sectional view along line 7B-7B'. Figure 8 (a) to (c) are schematic cross-sectional views of an OLED display device 100C, and Figure 8 (a) is along Figure 6 The cross-sectional view of line 8A-8A' in FIG. Figure 8 (b) is along Figure 6 The cross-sectional view of line 8B-8B' in FIG. Figure 8 (c) is along Figure 6 Cross-sectional view along line 8C-8C'.

[0077] The OLED display device 100C is different from the OLED display device 100 of the embodiment in that it does not include the inorganic protective layer 2Pa and the organic planarization layer 2Pbc is extended to the area not covered by the TFE structure 10C. In addition, the same reference numerals are given to the components substantially the same as those of the OLED display device 100A, and the description thereof is omitted.

[0078] For example, by Figure 6 , Figure 7 (b) and Figure 8 As can be seen from (b), a portion of the organic planarization layer 2Pbc is exposed to the atmosphere (surrounding atmosphere). As a result, the organic planarization layer 2Pbc absorbs moisture from the portion exposed to the atmosphere and guides water vapor in the atmosphere into the active region R1. Figure 3 (b) and Figure 4 As shown in (b), in the OLED display device 100A of the embodiment, the organic planarization layer 2Pb and the OLED layer 3 are surrounded by the connection portion where the inorganic protective layer 2Pa and the first inorganic barrier layer 12 are in direct contact. Therefore, the above-mentioned problem of the OLED display device 100C of the comparative example can be solved.

[0079] Next, refer to Fig. 9 as well as Fig.10 , an example of a TFT used in the OLED display device 100A, and an example of a lead wiring and a terminal formed using a gate metal layer and a source metal layer when manufacturing the TFT are described. The structures of the TFT, lead wiring and terminals described below can be used in the OLED display device 100A of the above embodiment.

[0080] In high-definition small and medium-sized OLED display devices, it is preferred to use a low-temperature polysilicon (abbreviated as "LTPS") TFT with high mobility, or an oxide TFT (for example, a quaternary system (In-Ga-Zn-O system) oxide TFT including In (indium), Ga (gallium), Zn (zinc), and O (oxygen)). Since the structure and manufacturing method of LTPS-TFT and In-Ga-Zn-O system TFT are well known, only a brief description is given below.

[0081] Fig. 9 (a) is LTPS-TFT2 P Schematic cross-sectional view of TFT2 P T may be included in the circuit 2 of the OLED display device 100A. LTPS-TFT2 P T is a top-gate TFT.

[0082] TFT2 P T is formed on the primer film 2P p (for example, a polyimide film) 1. Although the above description is omitted, it is preferred that a primer film formed of an inorganic insulator is formed on the substrate 1.

[0083] TFT2 P T has: formed on the base coating film 2 P Polysilicon layer 2 on p P se, formed on the polysilicon layer 2 P Gate insulation layer 2 on se P gi, formed on the gate insulating layer 2 P Gate electrode 2 on gi P g. Formed on the gate electrode 2 P Interlayer insulation layer 2 on g P i. Formed on the interlayer insulating layer 2 P Source electrode 2 on i P ss and drain electrode 2 P sd. Source electrode 2 P ss and drain electrode 2 P sd is formed in the interlayer insulating layer 2 P i and gate insulating layer 2 P gi contact holes, connected to the polysilicon layer 2 P source and drain regions of se.

[0084] Gate electrode 2 P g is included in the same gate metal layer as the gate bus, the source electrode 2 P ss and drain electrode 2 P sd is included in the same source metal layer as the source bus. The gate metal layer and the source metal layer can be used to form the lead wiring and terminals (see Fig.10 to be described later).

[0085] TFT2 P T is produced, for example, in the following manner.

[0086] As the substrate 1 , for example, a polyimide film having a thickness of 15 μm is prepared.

[0087] The primer film 2 is formed by plasma CVD method. P p(SiO2 film: 250nm / SiN x Film: 50nm / SiO2 film: 500nm (upper layer / middle layer / lower layer)) and a-Si film (40nm) are formed.

[0088] The a-Si film is subjected to a dehydrogenation treatment (eg, annealing at 450° C. for 180 minutes).

[0089] The a-Si film is converted into polysilicon by an excimer laser annealing (ELA) method.

[0090] The a-Si film is patterned in a photolithography process to form an active layer (semiconductor island).

[0091] A gate insulating film (SiO2 film: 50 nm) was formed by plasma CVD method.

[0092] The channel region of the active layer is doped (B + ).

[0093] A gate metal (Mo: 250 nm) is formed into a film by sputtering, and patterned by a photolithography process (including a dry etching process) (forming a gate electrode 2 P g and gate bus, etc.).

[0094] Doping is performed in the source and drain regions of the active layer (P + ).

[0095] Activation annealing (for example, annealing at 450° C. for 45 minutes) is performed. P se.

[0096] The interlayer insulating film (e.g. SiO2 film: 300nm / SiN x Film: 300nm (upper layer / lower layer)) film formation.

[0097] Contact holes are formed on the gate insulating film and the interlayer insulating film by dry etching. P i and gate insulating layer 2 P gi.

[0098] The source metal (Ti film: 100 nm / Al film: 300 nm / Ti film: 30 nm) is formed by sputtering and patterned by photolithography (including dry etching) (forming source electrode 2 P ss, drain electrode 2 P sd and source bus, etc.).

[0099] Thereafter, the inorganic protective layer 2Pa described above is formed by, for example, a plasma CVD method (see Figure 2 and Figure 3 ).

[0100] Fig. 9 (b) is an In-Ga-Zn-O TFT2 O Schematic cross-sectional view of TFT2 O TFT2 may be included in the circuit 2 of the OLED display device 100A. O T is a bottom-gate TFT.

[0101] TFT2O T Primer film 2 formed on substrate (eg polyimide film) 1 O p. TFT2 O T has: formed on the base coating film 2 O Gate electrode 2 on p O g; formed on the gate electrode 2 O The gate insulating layer 2 on g O gi; formed on the gate insulating layer 2 O Oxide semiconductor layer 2 on gi O se; and are respectively connected to the oxide semiconductor layer 2 O Source electrode 2 on the source region and drain region of se O ss and drain electrode 2 O sd. Source electrode 2 O ss and drain electrode 2 O sd is interlayer insulating layer 2 O i Cover.

[0102] Gate electrode 2 O g is included in the same gate metal layer as the gate bus, the source electrode 2 O ss and drain electrode 2 O sd is included in the same source metal layer as the source bus. The gate metal layer and the source metal layer are used to form the lead wiring and terminals, and the reference Fig.10 The structure described below.

[0103] The TFT 20T is produced, for example, as follows.

[0104] As the substrate 1 , for example, a polyimide film having a thickness of 15 μm is prepared.

[0105] The primer film 2 is formed by plasma CVD method. O p(SiO2 film: 250nm / SiN x Film: 50nm / SiO2 film: 500nm (upper layer / middle layer / lower layer)) film formation.

[0106] A gate metal (Cu film: 300 nm / Ti film: 30 nm (upper layer / lower layer)) is formed by sputtering and patterned by a photolithography process (including a dry etching process) (forming a gate electrode 2 O g and gate bus, etc.).

[0107] The gate insulating film (e.g. SiO2 film: 30nm / SiN x Film: 300nm (upper layer / lower layer)) film formation.

[0108] An oxide semiconductor film (In—Ga—Zn—O-based semiconductor film: 100 nm) was deposited by sputtering and patterned by a photolithography process (including a wet etching process) to form an active layer (semiconductor island).

[0109] The source metal (Ti film: 100 nm / Al film: 300 nm / Ti film: 30 nm (upper layer / middle layer / lower layer)) is formed by sputtering and patterned by photolithography (including dry etching) (forming source electrode 2 O ss, drain electrode 2 O sd and source bus, etc.).

[0110] Activation annealing (for example, annealing at 300° C. for 120 minutes) is performed. O se.

[0111] Thereafter, an interlayer insulating film 2 is formed as a protective film by a plasma CVD method. O i (e.g. SiN x film: 300nm / SiO2 film: 300nm (upper layer / lower layer)). The interlayer insulating layer 2 O i can also serve as the above-mentioned inorganic protective layer 2Pa (refer to Figure 2 as well as Figure 3 Of course, an inorganic protective layer 2Pa may be further formed on the interlayer insulating layer 2oi.

[0112] Next, refer to Fig.10 (a) to (c) illustrate the structure of another OLED display device according to another embodiment of the present invention. The circuit (bottom panel) 2 of the OLED display device has Fig. 9 TFT2 shown in (a) P T or Fig. 9 TFT2 shown in (b) O T, use to make TFT2 P T or TFT2 O The gate metal layer and the source metal layer at T form the lead wiring 32A and the terminal 34A. Fig.10 (a)~(c) are respectively Figure 4 In accordance with (b) to (d) of the present invention, "A" is added to the reference numerals of the corresponding components. Fig.10 The base coating film 2p in corresponds to Fig. 9 (a) The base coating film 2 P p and Fig. 9 (b) Primer film 2 O p, Fig.10 The gate insulating layer 2gi in corresponds to Fig. 9 (a) The gate insulating layer 2 Pgi and Fig. 9 (b) The gate insulating layer 2 O gi, Fig.10 The interlayer insulating layer 2i in Fig. 9 (a) The interlayer insulating layer 2 P i and Fig. 9 (b) The interlayer insulating layer 2 O i correspond respectively.

[0113] like Fig.10 As shown in (a) to (c) of FIG. 1 , the gate metal layer 2g and the source metal layer 2s are formed on the undercoat layer 2p formed on the substrate 1. Figure 3 and Figure 4 Although omitted in the figure, it is preferred that a primer film 2p formed of an inorganic insulator is formed on the substrate 1.

[0114] like Fig.10 As shown in (a) to (c), the lead wiring 32A and the terminal 34A are formed as a stack of the gate metal layer 2g and the source metal layer 2s. The portion of the lead wiring 32A and the terminal 34A formed by the gate metal layer 2g has, for example, the same cross-sectional shape as the gate bus, and the portion of the lead wiring 32A and the terminal 34A formed by the source metal layer 2s has, for example, the same cross-sectional shape as the source bus. For example, in the case of a 5.7-inch display device with a 500ppi, the line width of the portion formed by the gate metal layer 2g is, for example, 10μm, and the adjacent spacing is 16μm (L / S=10 / 16), and the line width of the portion formed by the source metal layer 2s is, for example, 16μm, and the adjacent spacing is 10μm (L / S=16 / 10). The cone angle θ is less than 90°, preferably less than 70°, and more preferably less than 60°. In addition, the cone angle of the portion formed under the organic planarization layer Pb may also be greater than 90°.

[0115] Next, refer to Figure 11 to Figure 14 , another embodiment of the present invention is described. According to the following embodiment, an organic EL device capable of improving luminous efficiency and a method for manufacturing the same are provided. In addition, although the OLED display device exemplified in the following embodiment has the structure of the OLED display device of the above embodiment, mass production and moisture resistance reliability are improved, the luminous efficiency can be improved independently of the above embodiment.

[0116] The OLED display device of the embodiment described below has: a substrate; a plurality of TFTs formed on the substrate; a plurality of gate bus lines and a plurality of source bus lines, each connected to any one of the plurality of TFTs; a plurality of terminals; a driving circuit layer having a plurality of lead wirings connecting the plurality of terminals to any one of the plurality of gate bus lines or the plurality of source bus lines; an interlayer insulating layer formed on the driving circuit layer; an organic EL element layer formed on the interlayer insulating layer and having a plurality of organic EL elements connected to any one of the plurality of TFTs; and a thin film sealing structure formed in a manner covering the organic EL element layer. The interlayer insulating layer has a contact hole, and a contact portion connecting the driving circuit layer and the organic EL element layer is formed in the contact hole, and the surface of the interlayer insulating layer is flush with the surface of the contact portion, and the arithmetic mean roughness Ra is less than 50nm.

[0117] That is, the arithmetic mean roughness Ra of the surface on which the OLED layer is formed is less than 50 nm, and thus the luminous efficiency is improved. Furthermore, since the arithmetic mean roughness Ra of the surface of the contact portion is also less than 50 nm, the luminous efficiency will not be reduced even if the contact portion is arranged in the pixel. Therefore, it is not necessary to avoid the contact portion to form the pixel, thereby increasing the degree of freedom of design and being able to increase the area ratio of the pixel.

[0118] The contact film having conductivity that forms the contact portion, i.e., the contact film that fills the contact hole of the interlayer insulating film, is formed of, for example, a material different from that of the lower electrode. For example, it is a laminated film of a titanium film and a copper film. The titanium film is formed, for example, by sputtering, and the copper film is formed on the titanium film by electroplating. For example, it can be formed by electroplating using the titanium film as a power supply layer.

[0119] By subjecting the surface of the contact film and the surface of the interlayer insulating film to chemical mechanical polishing, a surface having an arithmetic mean roughness Ra of 50 nm or less can be obtained.

[0120] For example, the interlayer insulating layer is formed on the driving circuit layer and has: a first inorganic protective layer, which exposes at least a plurality of terminals; an organic planarizing layer, which is formed on the first inorganic protective layer, and the arithmetic average roughness Ra of the surface of the organic planarizing layer is less than 50nm (refer to Fig.11 ).

[0121] Alternatively, the interlayer insulating layer is formed on the driving circuit layer and comprises: a first inorganic protective layer, which exposes at least a plurality of terminals; an organic planarization layer, which is formed on the first inorganic protective layer; and a second inorganic protective layer, which is formed on the organic planarization layer, and the arithmetic average roughness Ra of the surface of the second inorganic protective layer is less than 50nm (refer to Fig.13 ).

[0122] Reference Figures 11 to 14A structure of an OLED display device and a method for manufacturing the same according to another embodiment of the present invention will be described. Fig.11 The OLED display device 100D and Fig.13 The OLED display device 100E shown has Fig. 9 (a) shows the LTPS-TFT2 P T. Of course, it can also replace LTPS-TFT2 P T and use Fig. 9 In-Ga-Zn-O TFT2 shown in (b) O T, other well-known TFTs may also be used. Fig.11 (a) and Fig.13 In (a), a common wiring 2 electrically connected to the upper electrode (common electrode) 46 of the OLED is also shown. P c and contact part 2 P cv.

[0123] First, refer to Fig.11 and Fig.12 . Fig.11 (a) and (b) are schematic cross-sectional views of an OLED display device 100D, Fig.12 (a) to (c) are schematic cross-sectional views of a method for manufacturing the OLED display device 100D.

[0124] Fig.11 The OLED display device 100D shown in (a) has: a driving circuit layer 2, which has a plurality of TFTs formed on a substrate 1; an interlayer insulating layer formed on the driving circuit layer 2; an organic EL element layer 3 formed on the interlayer insulating layer; and a thin film encapsulation structure 10D, which is formed in a manner covering the organic EL element layer 3. The interlayer insulating layer here has an inorganic protective layer 2Pa and an organic planarization layer 2Pb formed on the inorganic protective layer 2Pa. The interlayer insulating layer, i.e., the inorganic protective layer 2Pa and the organic planarization layer 2Pb, has contact holes CH1 and CH2, and contact portions C1 and C2 connecting the driving circuit layer 2 and the organic EL element layer 3 are formed in the contact holes CH1 and CH2. The surface 2Pb_Sb of the organic planarization layer 2Pb is flush with the surface C_Sb of the contact portions C1 and C2, and the arithmetic mean roughness Ra is less than 50nm.

[0125] The OLED layer 3 is formed on the organic planarization layer 2Pb. The lower electrode and the organic layer (also referred to as the organic EL layer, including at least the organic light-emitting layer) of the OLED 3 require high flatness. When the flatness is low, for example, the light-emitting efficiency of the OLED 3 is reduced. The organic planarization layer 2Pb is formed by a liquid organic resin material (which may contain a solvent) applied to the surface of an element substrate (referred to as an element substrate for the sake of convenience in the manufacturing process), so that it can absorb the unevenness (height difference) of the base of the organic planarization layer 2Pb to form a flat surface. However, the surface of the organic resin film formed by the liquid resin material has a roughness (which may appear as "waviness") with an arithmetic mean roughness Ra exceeding 100nm to about 300nm (refer to Fig.12 (a)). If OLED 3 is formed on the organic planarization layer 2Pb having such surface roughness, the luminous efficiency cannot be sufficiently improved. For example, even if a micro-resonator structure is used, there is a problem that its effect cannot be fully manifested.

[0126] Furthermore, if the lower electrode and the organic layer are formed on the contact hole CH1 of the organic planarization layer 2Pb, a depression (recess) is formed on the lower electrode and the organic layer directly above the contact hole CH1. If the contact hole CH1 is set outside the pixel Pix, this problem can be avoided, but the area ratio of the pixel decreases.

[0127] Here, in the OLED display device 100D, the surface 2Pb_Sb of the organic planarization layer 2Pb is flush with the surfaces C_Sb of the contact parts C1 and C2 , and the arithmetic mean roughness Ra is less than 50 nm.

[0128] Here, refer to Fig.12 (a)~(c).

[0129] Fig.12 (a) schematically shows the state after the inorganic protective film 2Pa that becomes the inorganic protective layer 2Pa is formed on the driving circuit layer 2, and the organic planarizing film 2Pb that becomes the organic planarizing layer 2Pb is just formed. The thickness of the inorganic protective film 2Pa is, for example, greater than 100nm and less than 1000nm. The thickness of the organic planarizing film 2Pb is, for example, greater than 1000nm and less than 5000nm. The inorganic protective film 2Pa is selectively formed on the desired area through a metal mask. In addition, the organic planarizing film 2Pb is selectively coated and formed on the desired area of ​​the element substrate 20, and the entire surface is formed first, and then the unnecessary parts are removed. The inorganic protective film 2Pa is different from the inorganic protective layer 2Pa in that it does not have openings such as contact holes CH1 and CH2, and for simplicity, it is represented by the same reference numerals. Similarly, the organic planarizing film 2Pb is different from the organic planarizing layer 2Pb in that it does not have openings such as contact holes CH1 and CH2, but for simplicity, it is represented by the same reference numerals.

[0130] The surface 2Pb_Sa of the organic planarization film 2Pb immediately after formation has an arithmetic mean roughness Ra of more than 100 nm to about 300 nm. Fig.12 As shown in (b), the inorganic protective film 2Pa and the organic planarization film 2Pb are patterned to form contact holes CH1 and CH2. This patterning can be performed, for example, by dry etching using a mixed gas of O2 and CF4. Fig.11 As shown in (b), in order to form a portion where the inorganic protective layer 2Pa is in direct contact with the first inorganic barrier layer (not shown) constituting the TFE structure 10D, only the remaining portion of the inorganic protective layer 2Pa can be formed by using a multi-tone mask, for example.

[0131] When a conductive contact film C is formed on the patterned organic planarization film 2Pb, the surface C_Sa of the contact film C has a surface roughness, which reflects the surface roughness of the surface 2Pb_Sa of the organic planarization film 2Pb. The contact film C, for example, includes a titanium (Ti) film Ca and a copper (Cu) film Cb formed on the titanium film Ca. The titanium film Ca is formed, for example, by a sputtering method, and the copper film Cb is formed, for example, by a plating method. From the perspective of mass productivity, it is preferred to form the copper film Cb by electroplating using the titanium film Ca as a power supply layer. The thickness of the titanium film Ca is, for example, greater than 5 nm and less than 150 nm, and more preferably greater than 10 nm and less than 100 nm. The thickness of the copper (Cu) film Cb is, for example, greater than 1000 nm and less than 3000 nm, and more preferably greater than 1500 nm and less than 2500 nm.

[0132] Then, if Fig.12 As shown in (c), by chemical mechanical polishing the surface 2Pb_Sa of the organic planarization film 2Pb and the surface C_Sa of the contact film C, an organic planarization layer 2Pb with a smooth surface and contact parts C1 and C2 are obtained. The contact parts C1 and C2 respectively have C11 and C21 formed by the titanium film Ca and C12 and C22 formed by the copper film Cb. The surface 2Pb_Sb of the organic planarization layer 2Pb and the surface C_Sb of the contact layer C are flush, and the arithmetic average roughness Ra is less than 50nm.

[0133] Through Fig.12By performing CMP on the surface 2Pb_Sa of the organic planarization film 2Pb and the surface C_Sa of the contact film C (both Ra>50nm) shown in (b), it is possible to obtain the surface 2Pb_Sb and the surface C_Sb with an arithmetic average roughness Ra≤50nm. The arithmetic average roughness Ra of the surface 2Pb_Sb and the surface C_Sb of the contact film C is preferably 30nm or less. The arithmetic average roughness Ra is preferably smaller, and the lower limit value is not limited, but considering the relationship between the cost, time and effect required for CMP, the arithmetic average roughness Ra can be greater than 10nm, or it can be greater than 20nm.

[0134] Specifically, CMP can be performed using a slurry containing an oxidant such as hydrogen peroxide, an organic acid such as citric acid, or an amino acid such as glycine, and an abrasive such as a fumed silica or colloidal silica. Even if such an acidic solution is used, the polyimide substrate will not be corroded. In addition, a slurry containing aluminum oxide (Al2O3) powder can also be used. The load of the polishing pad is preferably 50 g / cm 2 Above 150g / cm 2 The rotation speed is preferably 20 rpm or more and 40 rpm or less. The time required for grinding is about 30 seconds to about 90 seconds.

[0135] In the OLED display device according to the embodiment of the present invention, the smoothing level required to suppress the reduction in luminous efficiency is about one order of magnitude lower than the smoothing level required by the ultra-LSI lithography process (the value of the arithmetic mean roughness Ra is about 10 times larger), and therefore, known abrasives used in CMP of copper wiring in semiconductor processes can be widely used.

[0136] The surface roughness can be measured using, for example, a confocal laser microscope or an atomic force microscope (AFM). The measurement range preferably includes the vicinity of the center of the pixel, and the reference length is appropriately set according to the surface roughness.

[0137] In this specification, in order to distinguish between planarization by the organic planarization layer 2Pb and planarization by CMP, planarization by CMP is referred to as “smoothing”.

[0138] Since the arithmetic mean roughness Ra of the surface on which the OLED layer 3 is formed is less than 50 nm, the luminous efficiency is improved. Furthermore, since the arithmetic mean roughness Ra of the surface C_Sb of the contact portions C1 and C2 is also less than 50 nm, the luminous efficiency will not be reduced even if the contact portion C1 is arranged in the pixel Pix. Therefore, it is not necessary to avoid the contact portion C1 to form the pixel Pix, thereby increasing the degree of freedom of design and being able to increase the area ratio of the pixel Pix.

[0139] Refer again Fig.11 .

[0140] Next, the lower electrode 42 and the upper electrode contact portion 43 are formed on the surface 2Pb_Sb of the organic planarizing film 2Pb and the surface C_Sb of the contact film C. The lower electrode 42 is connected to the drain electrode 2 via the contact hole C1. P sd is electrically connected. The lower electrode 42 includes, for example, a silver (Ag) layer and an ITO layer formed on the silver (Ag) layer. Ag is easy to form an alloy with Cu (the main constituent element of the contact portion C1) and can make the contact resistance substantially zero, so it is preferred. In the conventional structure without forming the contact portion C1, the drain electrode 2 is formed in the contact hole CH1. P The metal of sd is in contact with the ITO layer, and the contact resistance can be reduced by adopting the structure of this embodiment. The thickness of the silver layer is, for example, 50 nm to 150 nm, and the thickness of the ITO layer is, for example, 5 nm to 15 nm.

[0141] Next, a bank layer 48 is formed to define each of the plurality of pixels Pix. The bank layer 48 has an opening corresponding to the pixel Pix, and the side of the opening includes an inclined surface having a positive tapered side portion. The inclined surface of the bank layer 48 surrounds each pixel. The bank layer 48 is preferably formed using a photosensitive resin (such as polyimide or acrylic resin), for example. The thickness of the bank layer 48 is, for example, not less than 1 μm and not more than 2 μm. The inclination angle of the inclined surface of the bank layer 48 is not more than 60°. When the inclination angle θb of the inclined surface of the bank layer 48 exceeds 60°, there is a case where defects occur in the layer located above the bank layer 48.

[0142] As described above, in order to remove the moisture contained in the bank layer 48 and the moisture contained in the organic planarization layer 2Pb, heating (drying) is preferred. The heating temperature is preferably, for example, above 100°C (for example, for more than 1 hour), and more preferably above 250°C (for example, for more than 15 minutes). The atmosphere can be at atmospheric pressure. If heating is performed under a reduced pressure atmosphere, the heating time can be shortened. In order to prevent thermal degradation during the heating (baking) process, the bank layer 48 and the organic planarization layer 2Pb are preferably formed of a resin material with high heat resistance, such as preferably formed of polyimide.

[0143] Thereafter, the manufacturing of the element substrate may be interrupted, and the element substrate may be stored or transported. In this case, as described above, a positive photoresist film covering the surface of the element substrate formed up to the bank layer 48 may be formed. After storage or transport, a clean surface can be obtained by removing the photoresist film just before the organic layer 44 is formed. In addition, moisture contained in the organic planarization layer 2Pb and the bank layer 48 is removed by heating just before the organic layer 44 is formed.

[0144] Next, an organic layer 44 is formed on the lower electrode 42. The organic layer 44 is formed by, for example, vapor deposition. An upper electrode 46 is formed on the organic layer 44. The upper electrode 46 is in contact with the upper electrode contact portion 43 via the contact portion 2 P cv and common wiring 2 P cElectrical connection.

[0145] The lower electrode 42 and the upper electrode 46 constitute, for example, an anode and a cathode, respectively. The upper electrode 46 is a common electrode formed in the entire pixel in the active region, and the lower electrode (pixel electrode) 42 is formed for each pixel. If there is a bank layer 48 between the lower electrode 42 and the organic layer 44, holes are not injected from the lower electrode 42 to the organic layer 44. Therefore, since the area where the bank layer 48 exists does not function as a pixel Pix, the bank layer 48 defines the outer edge of the pixel Pix. The bank layer 48 is also called PDL (Pixel Definition Layer).

[0146] After the OLED 3 is formed in this way, a TFE structure 10D is formed. The TFE structure 10D has the same structure as the TFE structure 10A. That is, the TFE structure 10D has a first inorganic barrier layer (e.g., SiN) from the side close to the OLED 3. x layer) 12, an organic barrier layer 14, and a second inorganic barrier layer (e.g. SiN x Layer) 16. Fig.11 As shown in (b), the first inorganic barrier layer 12 is in contact with the upper surface and the inclined side surface of the organic planarization layer 2Pb and the upper surface of the inorganic protective layer 2Pa. That is, the OLED display device 100D has a first inorganic barrier layer 12 at its end. Figure 3 The OLED display device 100A shown in (b) has the same structure and has excellent moisture resistance reliability.

[0147] Next, refer to Fig.13 and Fig.14 An OLED display device 100E and a method for manufacturing the same according to another embodiment of the present invention will be described. Fig.13 (a) and (b) are schematic cross-sectional views of an OLED substrate 100E. Fig.14 (a) to (c) are schematic cross-sectional views for explaining a method for manufacturing the OLED display device 100E.

[0148] The OLED display device 100E is different from the OLED display device 100D in that the interlayer insulating layer formed between the driving circuit layer 2 and the OLED layer 3 has a second inorganic protective layer 2Pa2 formed on the organic planarization layer 2Pb. The first inorganic protective layer 2Pa1 of the OLED display device 100E is the same as the inorganic protective layer 2Pa of the OLED display device 100D. Fig.13 and Fig.14 Components common to those of the OLED display device 100D are denoted by common reference numerals, and description thereof is omitted.

[0149] like Fig.13 As shown in (a), the organic planarization layer 2Pb of the OLED display device 100E has a surface 2Pb_Sb with a large surface roughness (Ra>50nm), and the second inorganic protective layer 2Pa2 has a smoothed surface 2Pa2_Sb. The surface 2Pa2_Sb of the second inorganic protective layer 2Pa2 is flush with the surface C_Sb of the contact parts C1 and C2, and the arithmetic mean roughness Ra is less than 50nm. Therefore, the OLED display device 100E is similar to the OLED display device 100D, and the luminous efficiency is improved. Furthermore, the design freedom of the configuration of the contact part is increased, and the area ratio of the pixel can be improved at the same time.

[0150] In addition, if Fig.13 As shown in (b), the first inorganic barrier layer 12 is in contact with the upper surface and the inclined side surface of the second inorganic protective layer 2Pa2, the inclined side surface of the organic planarization layer 2Pb, and the upper surface of the first inorganic protective layer 2Pa1. Figure 3 The OLED display device 100A shown in (b) has the same structure and has excellent moisture resistance reliability.

[0151] Reference Fig.14 In (a) to (c), a method for manufacturing the OLED display device 100E is described. Here, the differences from the OLED display device 100D are mainly described.

[0152] like Fig.14 As shown in (a), a second inorganic protective film 2Pa2 is formed on the organic planarization layer 2Pb. The second inorganic protective film 2Pa2 is also selectively formed in a desired area using a mask in the same manner as the first inorganic protective film 2Pa1. The second inorganic protective film 2Pa2 is formed on the surface 2Pb_Sa of the organic planarization film 2Pb, and thus has the same degree of surface roughness (Ra>50nm) as the surface 2Pb_Sa of the organic planarization film 2Pb. For example, in the case of using SiN x When the second inorganic protective film 2Pa2 is formed by a plasma CVD method, for example, a SiN film having a thickness of 150 nm or more is formed at a film forming rate of not more than 10 nm / s. x film, thereby obtaining a second inorganic protective film 2Pa2 reflecting the surface roughness of the substrate.

[0153] Then, if Fig.14As shown in (b), the first inorganic protective film 2Pa1, the organic planarization film 2Pb, and the second inorganic protective film 2Pa2 formed in the desired area of ​​the element substrate 20 are patterned together to form openings such as contact holes CH1 and CH2. This patterning can be performed, for example, by dry etching using a mixed gas of O2 and CF4. In addition, as shown in FIG. Fig.13 As shown in (b), in order to form a portion where the first inorganic protective layer 2Pa1 is in direct contact with the first inorganic barrier layer (not shown) constituting the TFE structure 10E, only the remaining portion of the first inorganic protective layer 2Pa1 may be formed by using a multi-tone mask, for example.

[0154] Then, if Fig.14 As shown in (c), by chemically mechanically polishing the surface 2Pa2_Sa of the second inorganic planarization film 2Pa2 and the surface C_Sa of the contact film C, a second inorganic protective layer 2Pa2 and contact portions C1 and C2 having smooth surfaces are obtained. The surface 2Pa2_Sb of the second inorganic protective layer 2Pa2 and the surface C_Sb of the contact layer C are flush, and the arithmetic mean roughness Ra thereof is less than 50 nm. Chemical mechanical polishing can be performed in the same manner as described above.

[0155] Next, refer to Fig.15 (a) and (b) illustrate a film forming apparatus 200 for forming an organic barrier layer and a film forming method using the film forming apparatus 200. Fig.15 (a) and (b) are diagrams schematically showing the structure of the film forming apparatus 200. Fig.15 (a) shows the state of the film forming apparatus 200 in the process of condensing the photocurable resin on the first inorganic barrier layer in a chamber containing the vapor or mist of the photocurable resin. Fig.15 (b) shows the state of the film forming apparatus 200 in the step of irradiating light for photosensitizing the photocurable resin to cure the photocurable resin.

[0156] The film forming device 200 has a chamber 210 and a partition wall 234 that divides the interior of the chamber 210 into two spaces. In one space separated by the partition wall 234 in the interior of the chamber 210, a mounting table 212 and a shower plate 220 are arranged. In the other space separated by the partition wall 234, an ultraviolet irradiation device 230 is arranged. The chamber 210 controls the space inside it to a specified pressure (vacuum degree) and temperature. The mounting table 212 has an upper surface for receiving an element substrate 20, and the upper surface can be cooled to, for example, -20°C, wherein the element substrate 20 has a plurality of OLEDs 3 formed with a first inorganic barrier layer.

[0157] The shower plate 220 is configured to form a gap 224 between the shower plate 220 and the partition wall 234, and has a plurality of through holes 222. The vertical dimension of the gap 224 can be, for example, not less than 100 mm and not more than 1000 mm. The acrylic monomer (steam or mist) supplied to the gap 224 is supplied from the plurality of through holes 222 of the shower plate 220 to the space on the side of the mounting table 212 in the chamber 210. The acrylic monomer is heated as needed. The acrylic monomer 26p in the form of vapor or mist of the acrylic monomer adheres to or contacts the first inorganic barrier layer of the element substrate 20. The acrylic monomer 26 is supplied from the container 202 to the chamber 210 at a predetermined flow rate. The acrylic monomer 26 is supplied to the container 202 via the pipe 206, and nitrogen is supplied to the container 202 from the pipe 204. The flow rate of the acrylic monomer to the container 202 is controlled by the mass flow controller 208. The shower plate 220 , the container 202 , the pipes 204 and 206 , the mass flow controller 208 and the like constitute a raw material supply device.

[0158] The ultraviolet irradiation device 230 has an ultraviolet light source and an optional optical element. The ultraviolet light source may be, for example, an ultraviolet lamp (such as a mercury lamp (including high pressure, ultra-high pressure), a mercury xenon lamp or a metal halide lamp). The optical element may be, for example, a reflector, a prism, a lens and a diffraction element.

[0159] When the ultraviolet irradiation device 230 is arranged at a predetermined position, it emits light having a predetermined wavelength and intensity toward the upper surface of the mounting table 212. The partition wall 234 and the shower plate 220 are preferably formed of a material having a high transmittance of ultraviolet rays, such as quartz.

[0160] The organic barrier layer 14 can be formed, for example, in the following manner using the film forming apparatus 200. Here, an example in which an acrylic monomer is used as the photocurable resin will be described.

[0161] The acrylic monomer 26p is supplied into the chamber 210. The element substrate 20 is cooled to, for example, -15°C on the mounting table 212. The acrylic monomer 26p is condensed on the first inorganic barrier layer 12 of the element substrate 20. By controlling the conditions at this time, the liquid acrylic monomer can be concentrated only around the convex portion of the first inorganic barrier layer 12. Alternatively, the conditions are controlled so that the acrylic monomer condensed on the first inorganic barrier layer 12 forms a liquid film.

[0162] By adjusting the viscosity and / or surface tension of the liquid photocurable resin, the thickness of the liquid film and the shape (concave shape) of the portion of the first inorganic barrier layer 12 in contact with the convex portion can be controlled. For example, since the viscosity and surface tension depend on temperature, they can be controlled by adjusting the temperature of the element substrate. For example, the size of the solid portion existing on the flat portion can be controlled by the shape (concave shape) of the portion of the liquid film in contact with the convex portion of the first inorganic barrier layer 12 and the conditions of the subsequent ashing process.

[0163] Next, the ultraviolet irradiation device 230 is used to irradiate the entire upper surface of the element substrate 20 with ultraviolet rays 232 to cure the acrylic monomer on the first inorganic barrier layer 12. As the ultraviolet light source, for example, a high-pressure mercury lamp having a main peak at 365 nm is used, and as the ultraviolet intensity, for example, 12 mW / cm 2 , irradiate for about 10 seconds.

[0164] In this way, the organic barrier layer 14 made of acrylic resin is formed. The production time of the step of forming the organic barrier layer 14 is, for example, less than about 30 seconds, and the mass productivity is very high.

[0165] After curing the photocurable resin in the form of a liquid film, the organic barrier layer 14 may be formed only around the convex portion by ashing. In addition, ashing may be performed when the organic barrier layer 14 is formed by curing the photocurable resin that is unevenly present. The ashing process can improve the adhesion between the organic barrier layer 14 and the second inorganic barrier layer 16. That is, the ashing process is used not only to remove the excess portion of the temporarily formed organic barrier layer, but also to modify (hydrophilize) the surface of the organic barrier layer 14.

[0166] Ashing can be performed using a known plasma ashing device, a light-excited ashing device, or a UV ozone ashing device. For example, ashing can be performed by using plasma ashing of at least one gas selected from N2O, O2, and O3, or by further combining these gases with ultraviolet irradiation. x When the films are formed as the first inorganic barrier layer 12 and the second inorganic barrier layer 16, N2O is used as the raw material gas. Therefore, when N2O is used for ashing, there is an advantage that the apparatus can be simplified.

[0167] When ashing is performed, the surface of the organic barrier layer 14 is oxidized and modified to be hydrophilic. In addition, the surface of the organic barrier layer 14 is roughly uniformly cut and extremely finely concavoconvex is formed, and the surface area is increased. The surface area increase effect when ashing is performed is greater for the surface of the organic barrier layer 14 than for the first inorganic barrier layer 12 which is an inorganic material. Therefore, when the surface of the organic barrier layer 14 is modified to be hydrophilic, the surface area is increased, and thus the adhesion with the second inorganic barrier layer 16 is improved.

[0168] Thereafter, the organic barrier layer 14 is transported to a CVD chamber for forming the second inorganic barrier layer 16, and the second inorganic barrier layer 16 is formed under the same conditions as the first inorganic barrier layer 12. The second inorganic barrier layer 16 is formed in the region where the first inorganic barrier layer 12 is formed, so an inorganic barrier layer connection portion where the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are in direct contact is formed in the non-solid portion of the organic barrier layer 14. Therefore, as described above, water vapor in the atmosphere is suppressed and prevented from reaching the active region via the organic barrier layer.

[0169] In addition, the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are formed, for example, in the following manner. By using a plasma CVD method using SiH4 and N2O gases, for example, an inorganic barrier layer having a thickness of 400 nm can be formed at a film forming rate of 400 nm / min while the temperature of the substrate (OLED 3) to be film-formed is controlled to be below 80°C. The inorganic barrier layer thus obtained has a refractive index of 1.84 and a transmittance of 400 nm visible light of 90% (thickness 400 nm). In addition, the absolute value of the film stress is 50 MPa.

[0170] In addition, as an inorganic barrier layer, in addition to SiN x In addition to the SiO2 layer, SiO x N y (x>y) layer, SiN x O y (x>y) layer, Al2O3 layer, etc. The photocurable resin contains, for example, monomers containing vinyl groups. Among them, acrylic monomers are preferably used. Acrylic monomers can be mixed with photopolymerization initiators as needed. Various well-known acrylate monomers can be used. Multiple acrylic monomers can also be mixed. For example, bifunctional monomers and trifunctional or higher multifunctional monomers can also be mixed. In addition, oligomers can also be mixed. The viscosity of the photocurable resin at room temperature (for example, 25°C) before curing is preferably not more than 10Pa·s, and particularly preferably 1 to 100mPa·s. When the viscosity is high, it is sometimes difficult to form a thin liquid film with a thickness of less than 500nm.

[0171] In the above, although an OLED display device having a flexible substrate and a method for manufacturing the same are described, the embodiments of the present invention are not limited to the exemplified embodiments and can be widely applied to organic EL devices (e.g., organic EL lighting devices) having: an organic EL element formed on a substrate that is not flexible (e.g., a glass substrate) and a thin film packaging structure formed on the organic EL element. Industrial Applicability

[0172] Embodiments of the present invention are applicable to organic EL devices and methods for manufacturing the same. Embodiments of the present invention are particularly applicable to flexible organic EL display devices and methods for manufacturing the same. Description of Reference Numerals

[0173] 1: Flexible substrate 2: Baseboard (circuit) 2Pa: Inorganic protective layer (first inorganic protective layer), inorganic protective film (first inorganic protective film) 2Pa1: first inorganic protective layer, first inorganic protective film 2Pa2: Second inorganic protective layer, second inorganic protective film Pb: organic planarization layer, organic planarization film 3: Organic EL components: 4: Polarizing plate; 10: Thin film sealing structure (TFE structure) 12: The first inorganic barrier layer (SiN x layer) 14: Organic barrier layer (acrylic resin layer) 16: Second inorganic barrier layer (SiN x layer) 20: Component substrate 100, 100A, 100D, 100E: Organic EL display device 200: Film forming device.

Claims

1. An organic EL device, characterized in that: It includes: substrate; A driving circuit layer, comprising: a plurality of TFTs formed on the substrate, a plurality of gate bus lines and a plurality of source bus lines respectively connected to any one of the plurality of TFTs, a plurality of terminals, and a plurality of lead wirings connecting the plurality of terminals to any one of the plurality of gate bus lines or the plurality of source bus lines; an interlayer insulating layer formed on the driving circuit layer; an organic EL element layer formed on the interlayer insulating layer and having a plurality of organic EL elements respectively connected to any one of the plurality of TFTs; as well as a thin film sealing structure formed so as to cover the organic EL element layer, The interlayer insulating layer has a contact hole, A contact portion connecting the driving circuit layer and the organic EL element layer is formed in the contact hole. The interlayer insulating layer includes: a first inorganic protective layer which at least exposes the plurality of terminals; and an organic planarization layer which is formed on the first inorganic protective layer. The thin film sealing structure has: a first inorganic barrier layer, an organic barrier layer in contact with an upper surface of the first inorganic barrier layer, and a second inorganic barrier layer in contact with an upper surface of the organic barrier layer, wherein the organic barrier layer is formed in a region surrounded by an inorganic barrier layer connecting portion where the first inorganic barrier layer and the second inorganic barrier layer are in direct contact with each other, When observed from the normal direction of the substrate, the organic planarization layer is formed in the region where the first inorganic protective layer is formed, the plurality of organic EL elements are arranged in the region where the organic planarization layer is formed, the outer edge of the thin film sealing structure intersects the plurality of lead wirings and exists between the outer edge of the organic planarization layer and the outer edge of the first inorganic protective layer, In portions of the lead wirings where the first inorganic protective layer and the first inorganic barrier layer are in direct contact, a taper angle of a side surface of the first inorganic barrier layer in a cross-sectional shape parallel to the line width direction of the lead wirings is less than 90°.

2. The organic EL device according to claim 1, characterized in that: The organic EL device has a plurality of pixels, each of which includes one of the plurality of organic EL elements. The contact portion is formed inside each of the plurality of pixels.

3. The organic EL device according to claim 2, characterized in that: The plurality of organic EL elements include a lower electrode, an organic layer, and an upper electrode facing the lower electrode via the organic layer. The contact portion is formed of a material different from that of the lower electrode.

4. The organic EL device according to any one of claims 1 to 3, characterized in that: The organic planarization layer has a surface with an arithmetic mean roughness Ra of 50 nm or less.

5. The organic EL device according to any one of claims 1 to 3, characterized in that: The interlayer insulating layer further includes a second inorganic protective layer formed on the organic planarizing layer, wherein the arithmetic mean roughness Ra of a surface of the second inorganic protective layer is 50 nm or less.

6. The organic EL device according to claim 1, wherein: The taper angle of the side surface of the first inorganic barrier layer is less than 70°.

7. The organic EL device according to claim 1 or 6, characterized in that: The organic planarization layer is formed of polyimide.

8. A manufacturing method, which is the manufacturing method of the organic EL device according to any one of claims 1 to 3, characterized in that: The manufacturing method comprises: Step A, forming the driving circuit layer on the substrate; Step B, forming an interlayer insulating film having a contact hole on the driving circuit layer; Step C of forming a contact film having conductivity and covering the interlayer insulating film; and Step D is to obtain the interlayer insulating layer and the contact portion by performing chemical mechanical polishing on the surface of the contact film and the surface of the interlayer insulating film.

9. The manufacturing method according to claim 8, characterized in that: The process C comprises: forming a titanium film by sputtering; and A step of forming a copper film on the titanium film by a plating method.

10. The manufacturing method according to claim 8 or 9, characterized in that: The process B comprises: forming a first inorganic protective film on the driving circuit layer; and forming an organic planarization film on the first inorganic protective film, The manufacturing method further comprises: After the step D, a step E of heating the interlayer insulating layer to a temperature of 100° C. or higher; After the step E, a step F of forming an organic layer included in the organic EL element on the interlayer insulating layer is performed.

11. The manufacturing method according to claim 10, characterized in that: The step D includes a step of performing chemical mechanical polishing on the surface of the organic planarization film.

12. The manufacturing method according to claim 8 or 9, characterized in that: The process B comprises: forming a first inorganic protective film on the driving circuit layer; forming an organic planarization film on the first inorganic protective film; forming a second inorganic protective film on the organic planarization film; a step of forming a contact hole penetrating the first inorganic protective film, the organic planarization film, and the second inorganic protective film at the same time; The step D includes a step of performing chemical mechanical polishing on the surface of the second inorganic protective film.

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