阅读说明：本技术 有机el设备及其制造方法 (Organic EL device and method for manufacturing the same ) 是由 岸本克彦 鸣泷阳三 于 2017-07-13 设计创作，主要内容包括：实施方式所涉及的有机EL设备(100)具备：元件基板(20),其具有基板(1)和被基板支撑的多个有机EL元件(3)；薄膜封装结构(10),所述薄膜封装结构(10)是形成于所述多个有机EL元件上的薄膜封装结构,其具有由第一无机阻挡层(12)、有机阻挡层(14)、第二无机阻挡层(16)构成的至少一个的复合层叠体(10S),所述有机阻挡层(14)具有与所述第一无机阻挡层的上表面接触且分散分布的多个实心部,所述第二无机阻挡层(16)与所述第一无机阻挡层的上表面及所述有机阻挡层的多个实心部的上表面接触；有机平坦化层(42),其设置在所述薄膜封装结构之上由光敏树脂形成；触摸传感层(50),其被配置在有机平坦化层之上。(An organic EL device (100) according to an embodiment includes: an element substrate (20) having a substrate (1) and a plurality of organic EL elements (3) supported by the substrate; a thin film encapsulation structure (10), wherein the thin film encapsulation structure (10) is formed on the plurality of organic EL elements, and has a composite laminate (10S) including at least one of a first inorganic barrier layer (12), an organic barrier layer (14), and a second inorganic barrier layer (16), the organic barrier layer (14) has a plurality of solid portions in contact with and distributed over an upper surface of the first inorganic barrier layer, and the second inorganic barrier layer (16) is in contact with an upper surface of the first inorganic barrier layer and upper surfaces of the plurality of solid portions of the organic barrier layer; an organic planarization layer (42) formed of a photosensitive resin disposed over the thin film encapsulation structure; a touch sensing layer (50) disposed over the organic planarization layer.)

1. An organic EL device, characterized by comprising:

an element substrate having a substrate and a plurality of organic EL elements supported by the substrate;

a thin film encapsulation structure formed on the plurality of organic EL elements, the thin film encapsulation structure including at least one composite laminate composed of a first inorganic barrier layer, an organic barrier layer, and a second inorganic barrier layer, the organic barrier layer including a plurality of solid portions in contact with and distributed over an upper surface of the first inorganic barrier layer, the second inorganic barrier layer being in contact with the upper surface of the first inorganic barrier layer and upper surfaces of the plurality of solid portions of the organic barrier layer;

an organic planarization layer, which is disposed on the thin film encapsulation structure, and is composed of photosensitive resin;

a touch sensing layer disposed on the organic planarization layer.

2. The organic EL device according to claim 1, wherein the photosensitive resin is negative.

3. The organic EL device according to claim 1 or 2, wherein the thickness of the organic planarizing layer is not more than 15 μm.

4. The organic EL device according to any one of claims 1 to 3, wherein the photosensitive resin comprises a silicone resin.

5. The organic EL device according to any one of claims 1 to 4, wherein the organic planarizing layer has a transmittance of more than 80% for light of 350 nm.

6. The organic EL device according to any one of claims 1 to 4, wherein the photosensitive resin has an elastic modulus at 0 ℃ of not more than 400 MPa.

7. The organic EL device according to any one of claims 1 to 5, further comprising an inorganic insulating layer covering the organic planarization layer, wherein the touch sensing layer is formed on the inorganic insulating layer.

8. The organic EL device according to any one of claims 1 to 7, wherein the organic planarization layer covers at least an entire active region where the plurality of organic EL elements are arranged, and is formed in a larger range than the touch sensing layer.

9. The organic EL device according to any one of claims 1 to 8, wherein the organic planarization layer covers the entire element substrate.

10. The organic EL device according to any one of claims 1 to 9, wherein the plurality of solid portions include a plurality of solid portions having concave surfaces.

11. The organic EL device according to any one of claims 1 to 10, further comprising a drive circuit supported by the substrate, a plurality of terminals arranged in a peripheral region, and a plurality of lead lines connected to the drive circuit and the plurality of terminals,

the thin film encapsulation structure is disposed over the drive circuit side portion of the plurality of lead-out wirings, and the organic barrier layer is not present on each of the plurality of lead-out wirings, but has an inorganic barrier layer junction where the first inorganic barrier layer and the second inorganic barrier layer are in direct contact.

12. A method for manufacturing an organic EL device according to any one of claims 1 to 11,

the step of forming the organic planarization layer includes:

a step a of preparing the element substrate on which the thin film encapsulation structure is formed;

a step B of applying a liquid containing a negative photosensitive resin onto the element substrate so as to cover at least the thin film encapsulation structure;

and a step C of irradiating the entire photosensitive resin on the element substrate with light.

13. The manufacturing method according to claim 12, wherein the step B is performed by applying the liquid only to a predetermined region on the element substrate.

14. A method for manufacturing an organic EL device according to any one of claims 1 to 11,

the step of forming the organic planarization layer includes:

a step a of preparing the element substrate on which the thin film encapsulation structure is formed;

a step B of applying a liquid containing a photosensitive resin onto the element substrate so as to cover at least the thin film encapsulation structure;

a step C of selectively irradiating the photosensitive resin present in a predetermined region or a region other than the predetermined region on the element substrate with light;

and a step D of bringing the photosensitive resin into contact with a developer after the step C.

15. The method according to any one of claims 12 to 14, wherein the step of forming the at least one composite laminate comprises

Preparing the element substrate on which the first inorganic barrier layer is formed into a container,

A step of supplying a vapor or mist of a photocurable resin into the container,

A step of forming a liquid film by condensing the photocurable resin on the first inorganic barrier layer,

A step of forming a photocurable resin layer by irradiating the liquid film of the photocurable resin with light,

And forming the organic barrier layer by partially ashing the photocurable resin layer.

Technical Field

The present invention relates to an organic EL device (e.g., an organic EL display device and an organic EL lighting device) and a method of manufacturing the same.

Background

Organic el (electro luminescence) display devices have been put to practical use. One of the characteristics of the organic EL display device is that a flexible display device can be obtained. The Organic EL display device has at least one Organic EL element (OLED) for each pixel and at least one tft (thin Film transistor) that controls current supplied to each OLED. Hereinafter, the organic EL display device is referred to as an OLED display device. Such an OLED display device having switching elements such as TFTs per OLED is called an active matrix type OLED display device. The substrate on which the TFT and the OLED are formed is referred to as an element substrate.

OLEDs (particularly, organic light-emitting layers and cathode electrode materials) are susceptible to deterioration by moisture and are also prone to display unevenness. As a technique for protecting OLEDs from moisture and providing an Encapsulation structure that does not deteriorate flexibility, a Thin Film Encapsulation Technique (TFE) has been developed. The thin film encapsulation technique is a technique in which an inorganic barrier layer and an organic barrier layer are laminated on each other to obtain a sufficient vapor barrier property through a thin film. From the viewpoint of moisture resistance of the OLED display device, the organic light emitting diodeWVTR (Water Vapor Transmission Rate: WVTR) of thin film packaging structure is generally required to be less than 1X 10^-4g/m²/day。

The thin film encapsulation structure currently sold in the market for use in the OLED display device has an organic barrier layer (polymer barrier layer) having a thickness of about 5 to 20 μm. Such a thick organic barrier layer plays a role of planarizing the surface of the element substrate. However, there is a problem in that when the organic barrier layer is thick, the bending of the OLED display device may be limited.

In addition, there is a problem that mass productivity is low. The thick organic barrier layer is formed using a printing technique such as an inkjet method or a micro-jet method. On the other hand, the inorganic barrier layer is formed using a thin film forming technique under an atmosphere of vacuum (for example, less than 1 Pa). Since the formation of the organic barrier layer using the printing technique is performed in the air or nitrogen atmosphere and the formation of the inorganic barrier layer is performed in a vacuum, the mass productivity is low by taking the element substrate out of the vacuum vessel in the process of forming the thin film encapsulation structure.

Here, for example, as disclosed in patent document 1, a film forming apparatus capable of continuously producing an inorganic barrier layer and an organic barrier layer has been developed.

Patent document 2 discloses a thin film encapsulation structure in which, when a first inorganic barrier layer, a first resin material, and a second inorganic material layer are formed in this order from the element substrate side, the first resin material is made uneven around a convex portion of the first inorganic material layer (the first inorganic material layer covering the convex portion). According to patent document 2, the first resin material is unevenly distributed around a certain convex portion that may not be sufficiently covered with the first inorganic material layer, thereby suppressing intrusion of moisture or oxygen from that portion. In addition, by using the first resin material as the base layer of the second inorganic material layer, the second inorganic material layer is appropriately formed, and the side surface of the first inorganic material layer can be appropriately covered with a desired film thickness. The first resin material is formed as follows. The vaporized organic material in the form of mist is supplied to an element substrate maintained at a temperature of room temperature or lower, and the organic material is condensed and dropped on the substrate. The organic material in a droplet state moves on the substrate by capillary phenomenon or surface tension, and is unevenly distributed at the boundary between the side surface of the convex portion of the first inorganic material layer and the surface of the substrate. Thereafter, the organic material is cured to form a first resin material at the boundary portion. Patent document 3 also discloses an OLED display device having the same thin film encapsulation structure. In addition, patent document 4 discloses a film formation apparatus used for manufacturing an OLED display device.

It is considered that the thin film encapsulation structure having an organic barrier layer made of a resin unevenly distributed as described in patent document 2 or 3 does not have a thick organic barrier layer, and thus the flexibility of the OLED display device is improved. In addition, since the inorganic barrier layer and the organic barrier layer can be formed continuously, mass productivity is also improved.

However, according to the studies of the present inventors, there is a problem that sufficient moisture resistance reliability cannot be obtained when the organic barrier layer is formed by the method described in patent document 2 or 3. It has been found that this problem is caused by water vapor in the atmosphere reaching an active region (also referred to as an "element formation region" or a "display region") on the element substrate via the organic barrier layer.

When the organic barrier layer is formed using a printing method such as an inkjet method, the organic barrier layer can be formed only in an active region (also referred to as an "element formation region" or a "display region") on the element substrate, and not in a region other than the active region. Therefore, a region where the first inorganic material layer and the second inorganic material layer are in direct contact exists at the periphery (outside) of the active region, and the organic barrier layer is completely surrounded by the first inorganic material layer and the second inorganic material layer, being insulated from the surroundings.

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 element substrate, and the resin is unevenly distributed at the boundary between the side surface of the convex portion of the surface of the element substrate and the substrate surface by the surface tension of the liquid resin. Therefore, the organic barrier layer is formed in a region other than the active region (also referred to as a "peripheral region"), that is, a terminal region in which a plurality of terminals are arranged and a lead-out wiring region in which lead-out wirings are formed from the active region to the terminal region. Specifically, for example, the resin is unevenly distributed at the boundary between the side surface of the lead-out wiring and the terminal and the surface of the substrate. In this way, the end portion of the organic barrier layer formed along the lead line is exposed to the air (ambient atmosphere) without being surrounded by the first inorganic barrier layer and the second inorganic barrier layer.

Since the organic barrier layer has lower water vapor barrier properties than the inorganic barrier layer, the organic barrier layer formed along the lead line serves as a path for guiding water vapor in the air into the active region.

Further, the film package structure having an organic barrier layer formed of a conventional uneven resin also has the following problems.

For example, in an OLED display device having a touch panel function used in a smartphone or a tablet terminal, as described in patent document 5, an organic barrier layer of a thin film encapsulation structure is thick and functions as a planarization layer, and a touch sensing layer (also referred to as a "touch panel layer") is provided on a flat surface of the thin film encapsulation structure via a connection layer. In the structure in which the touch sensor layer is provided on the thin film encapsulation structure, as described in patent document 2 or 3, when particles (foreign substances) are present in the thin film encapsulation structure, if the thin film encapsulation structure having a thin organic barrier layer is used, the upper surface of the thin film encapsulation structure becomes uneven, and therefore, strain is generated in the touch sensor layer, and as a result, there is a possibility that a problem of lowering the function of the touch panel may occur. For example, in a resistive film type touch sensor having a fine gap between a pair of electrodes and a projected capacitance type touch sensor that detects a change in capacitance between the electrodes, there is a possibility that a place where a particle exists is erroneously recognized as a touched position.

Here, the problem of the thin film encapsulation structure applied to the flexible OLED display device is described, but the thin film encapsulation structure is not limited to the OLED display device, and may be used in other organic EL devices such as an organic EL lighting device.

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made to solve the above problems, and an object of the present invention is to provide an organic EL device having a thin film encapsulation structure with a thin organic barrier layer, which has improved mass productivity and moisture-proof reliability, and in which a decrease in touch panel function is suppressed, and a method for manufacturing the same.

Means for solving the problems

In an organic EL device according to an embodiment of the present invention, the organic EL device includes: an element substrate having a substrate and a plurality of organic EL elements supported by the substrate; a thin film encapsulation structure formed on the plurality of organic EL elements, the thin film encapsulation structure including a composite laminate of at least one of a first inorganic barrier layer, an organic barrier layer, and a second inorganic barrier layer, the organic barrier layer having a plurality of solid portions in contact with and distributed over an upper surface of the first inorganic barrier layer, the second inorganic barrier layer being in contact with the upper surface of the first inorganic barrier layer and upper surfaces of the plurality of solid portions of the organic barrier layer; an organic planarization layer, which is disposed on the thin film encapsulation structure, and is composed of photosensitive resin; a touch sensing layer disposed on the organic planarization layer. The "solid portion" refers to a portion where an organic film (for example, a photocurable resin film) is actually present in the organic barrier layer. On the contrary, a portion where the organic film is not present is referred to as a non-solid portion. The non-solid portion surrounding the solid portion may be referred to as an opening portion.

In one embodiment, the plurality of solid portions having the organic barrier layer include a plurality of solid portions having concave surfaces.

In one embodiment, the organic barrier layer is formed of a photocurable resin (a material that cures a photocurable resin). The photocurable resin is preferably an ultraviolet curable resin, and is suitable for use in, for example, an acrylic resin (acrylic monomer (including oligomer).

In one embodiment, the first and second inorganic barrier layers are each independently SiN having a thickness of greater than 200nm and less than 1000nm_xAnd (3) a layer.

In one embodiment, the photosensitive resin is negative.

In a certain embodiment, the organic planarization layer has a thickness of no more than 15 μm. The organic planarization layer has a thickness of, for example, greater than 3 μm.

In a certain embodiment, the photosensitive resin comprises silicone. The photosensitive resin may also be an acrylic resin.

In a certain embodiment, the organic planarization layer has a transmittance of greater than 80% for 350nm light.

In a certain embodiment, the photosensitive resin has an elastic modulus at 0 ℃ of not more than 400 MPa.

In one embodiment, the touch sensor further includes an inorganic insulating layer covering the organic planarization layer, and the touch sensing layer is formed on the inorganic insulating layer. The passive insulating layer is, for example, SiN_xAnd (3) a layer. The SiN_xThe thickness of the layer is for example greater than 200nm and less than 1000 nm.

In one embodiment, the organic planarization layer covers at least the entire active region where the plurality of organic EL elements are arranged, and is formed in a larger range than the touch sensing layer.

In one embodiment, the organic planarization layer covers the entire element substrate.

In one embodiment, the thin film encapsulation structure further includes a drive circuit supported by the substrate, a plurality of terminals arranged in a peripheral region, and a plurality of lead lines connected to the drive circuit and the plurality of terminals, wherein the thin film encapsulation structure is provided on a portion of the plurality of lead lines on the drive circuit side, and the organic barrier layer is not present on each portion of the plurality of lead lines, and the thin film encapsulation structure has an inorganic barrier layer junction where the first inorganic barrier layer and the second inorganic barrier layer are in direct contact with each other. A taper angle of a side surface of a shape of a cross section parallel to a width direction of the plurality of lead-out wirings is preferably less than 90 °, and the taper angle of the side surface of the first inorganic barrier layer is preferably less than 70 °. The length of the junction of the inorganic barrier layer is preferably at least 0.01 nm.

A method for manufacturing an organic EL device according to an embodiment of the present invention is a method for manufacturing any one of the organic EL devices, and the step of forming the organic planarizing layer includes: a step a of preparing the element substrate on which the thin film encapsulation structure is formed; a step B of applying a liquid containing a negative photosensitive resin onto the element substrate so as to cover at least the thin film encapsulation structure; and a step C of irradiating the entire photosensitive resin on the element substrate with light.

In one embodiment, the step B is performed by applying the liquid to only a predetermined region on the element substrate. The step B can be performed by a known printing method (for example, an ink jet method and a screen printing method).

A method for manufacturing an organic EL device according to another embodiment of the present invention is a method for manufacturing any one of the organic EL devices, and the step of forming the organic planarizing layer includes: a step a of preparing the element substrate on which the thin film encapsulation structure is formed; a step B of applying a liquid containing a negative photosensitive resin onto the element substrate so as to cover at least the thin film encapsulation structure; a step C of selectively irradiating the photosensitive resin present in a predetermined region or a region other than the predetermined region on the element substrate with light; and a step D of bringing the photosensitive resin into contact with a developer after the step C. The step B may be a step of applying a liquid containing the photosensitive resin to the entire element substrate. In this case, a step of connecting an external substrate to the plurality of terminals of the element substrate may be included before the step B.

In one embodiment of the present invention, the step of forming the at least one composite laminate includes a step of preparing the element substrate on which the first inorganic barrier layer is formed into a container, a step of supplying a vapor or mist of the photocurable resin into the container, a step of forming a liquid film by condensing the photocurable resin on the first inorganic barrier layer, a step of forming a photocurable resin layer by irradiating light to the liquid film of the photocurable resin, and a step of forming the organic barrier layer by partially ashing the photocurable resin layer. The thickness of the liquid film and/or the ashing conditions can be adjusted to adjust the region and thickness of the photocurable resin remaining therein.

In one embodiment, the ashing device is formed by using N₂O、O₂And O₃The plasma ashing method of at least one gas of (1).

In one embodiment, the step of forming the at least one composite laminate may include a step of forming the organic barrier layer by a method described in patent document 2 or 3. According to this method, the photocurable resin can be made uneven at the boundary between the side surface (taper angle greater than 90 °) of the convex portion of the first inorganic barrier layer and the flat portion. A taper angle of a side surface of a shape of a cross section parallel to a width direction of the plurality of lead-out wirings is preferably less than 90 °, and the taper angle of the side surface of the first inorganic barrier layer is preferably less than 70 °.

Advantageous effects

According to an embodiment of the present invention, there is provided a method for manufacturing an organic EL device having a thin film encapsulation structure with a thin organic barrier layer, which has improved mass productivity and moisture resistance reliability, and in which a decrease in touch panel function is suppressed.

Drawings

Fig. 1 (a) is a schematic partial sectional view of an active region of an OLED display device 100 according to an embodiment of the present invention, and (b) is a partial sectional view of a TFE structure 10 formed on an OLED 3.

Fig. 2 is a plan view schematically showing the structure (under the TFE structure 10) of the OLED display device 100 according to the embodiment of the present invention.

Fig. 3 (a) and (B) are plan views schematically showing the structures (on the TFE structure 10) of the OLED display devices 100A and 100B according to the embodiment of the present invention.

Fig. 4 (a) to (C) are schematic sectional views of the OLED display device 100A shown in fig. 3 (a), (a) is a sectional view taken along line 4A-4A 'in fig. 3, (B) is a sectional view taken along line 4B-4B' in fig. 3, (C) is a sectional view taken along line 4C-4C 'in fig. 3, and (d) is a sectional view of the OLED display device 100C of the comparative example, corresponding to a sectional view taken along line 4B-4B' in fig. 3.

Fig. 5 (a) and (b) are diagrams schematically showing the structure of a touch sensing layer 50A that can be provided with an OLED display device according to an embodiment of the present invention.

Fig. 6 (a) and (B) are diagrams schematically showing the structure of another touch sensing layer 50B that may be provided with the OLED display device 1 according to the embodiment of the present invention.

Fig. 7(a) and (b) are schematic cross-sectional views each showing an example of a TFT which can be provided with the OLED display device according to the embodiment of the present invention.

Fig. 8 (a) and (b) are schematic cross-sections of another OLED display device according to the embodiment, and correspond to fig. 4 (a) and (c), respectively.

Fig. 9 (a) and (b) are views schematically showing the structure of the film formation apparatus 200.

Detailed Description

Hereinafter, an OLED display device and a method for manufacturing the same according to embodiments of the present invention will be described with reference to the accompanying drawings. Furthermore, the embodiments of the present invention are not limited to the following exemplary embodiments.

The basic configuration of the OLED display device 100 according to the embodiment of the present invention will be described with reference to (a) and (b) of fig. 1. Fig. 1 (a) is a schematic partial sectional view of an active region of an OLED display device 100 according to an embodiment of the present invention, and fig. 1 (b) is a partial sectional view of a TFE structure 10 formed on an OLED 3.

The OLED display device 100 has a plurality of pixels each having at least one organic EL element (OLED). Here, for the sake of simplicity, a description will be given of a structure corresponding to one OELD.

As shown in fig. 1 (a), the OLED display device 100 has: a flexible substrate (hereinafter, sometimes simply referred to as "substrate") 1, a circuit (backplane) 2 including TFTs formed on the substrate 1, an OLED3 formed on the circuit 2, and a TFE structure 10 formed on the OLED 3. The OLED3 is, for example, top-emitting. The uppermost portion of the OLED3 is, for example, an upper electrode or cap layer (refractive index adjustment layer). The OLED display device 100 further has an organic planarization layer 42 formed of a photosensitive resin disposed on the thin film encapsulation structure 10, an inorganic insulating layer 44 covering the organic planarization layer 42, and a touch sensing layer 50 disposed on the inorganic insulating layer 44. The inorganic insulating layer 44 may also be omitted. An optional polarizer 4 is disposed on the touch sensing layer 50. The polarizing plate 4 may be disposed between the TFE structure 10 and the touch sensing layer 50 (e.g., between the organic planarization layer 42 and the touch sensing layer 50). The polarizing plate 4 is a circular polarizing plate (a laminate of a linear polarizing plate and a λ/4 plate), and as is well known, has an effect of preventing reflection. From the viewpoint of preventing reflection, as shown in the drawing, it is preferable that the polarizing plate 4 is disposed on the touch sensor layer 50.

For example, the substrate 1 is a polyimide film having a thickness of 15 μm. For example, the thickness of the circuit 2 containing the TFTs is 4 μm, the thickness of the OLED3 is 1 μm, and the thickness of the TFE structure 10 is less than 1.5 μm. For example, the organic planarization layer 42 has a thickness of more than 3 μm and less than 15 μm. For example, the passive insulating layer 44 is SiN_xAnd (3) a layer. For example, SiN_xThe thickness of the layer is greater than 200nm and less than 1000 nm.

Fig. 1 (b) is a partial cross-sectional view of a TFE structure 10 formed on an OLED 3. A first inorganic barrier layer (e.g., SiN) is formed directly over OLED3_xLayer) 12, an organic barrier layer (e.g., an acrylic resin layer) 14 formed on the first inorganic barrier layer 12, and a second inorganic barrier layer (e.g., SiN) formed on the organic barrier layer 14_xLayer) 16.

The organic barrier layer 14 has a plurality of solid portions in contact with the upper surface of the first inorganic barrier layer 12 and distributed dispersedly. The "solid portion" refers to a portion where an organic film (for example, a photocurable resin film) is actually present in the organic barrier layer 14. On the contrary, a portion where the organic film is not present is referred to as a non-solid portion. The non-solid portion surrounding the solid portion may be referred to as an opening. The second inorganic barrier layer 16 is in contact with the upper surface of the first inorganic barrier layer and the upper portions of the plurality of solid portions of the organic barrier layer 14. That is, the second inorganic barrier layer 16 directly contacts the first inorganic barrier layer 12 in a non-solid portion of the organic barrier layer 14.

The TFE structure 10 is formed in such a manner as to protect an active region (refer to an active region R1 in fig. 2) of the OLED display device 100. The non-solid portion of the organic barrier layer 14 includes at least a portion continuous so as to surround the active region R1, and the active region R1 is completely surrounded by a portion in direct contact with the first inorganic barrier layer 12 and the second inorganic barrier layer 16 (hereinafter referred to as an "inorganic barrier layer junction"). Therefore, the solid portion of the organic barrier layer 14 does not become a path for moisture.

The laminated structure including the first inorganic barrier layer 12 and the second inorganic barrier layer 16 included in the TFE structure 10 is referred to as a composite laminate (10S), and the second inorganic barrier layer 16 is in contact with the upper surface of the first inorganic barrier layer 12 and the upper surfaces of the plurality of solid portions of the organic barrier layer 14. Although the TFE structure 10 is formed of one composite laminate 10S, the TFE structure may have two or more composite laminates 10S, or may further have an organic insulating layer and/or an inorganic insulating layer. When the composite laminate 10S is provided as the TFE structure in the uppermost layer, a highly reliable package can be realized.

For example, the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are, for example, 400nm thick SiN_xThe organic barrier layer 14 is, for example, an acrylic resin layer having a thickness of less than 100 nm.

The thicknesses of the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are preferably independent of each other, for example, greater than 200nm and less than 1500nm, and preferably less than 1000 nm. For example, the organic barrier layer 14 has a thickness of greater than 10nm and less than 500nm, preferably greater than 50nm and less than 300 nm. When the thickness is less than 50nm, the effect of the organic barrier layer 14 is not sufficiently exhibited, whereas when the thickness is more than 500nm, the effect of the organic barrier layer 14 is saturated, which increases the manufacturing cost. The thickness of the composite laminate 10S is preferably greater than 500nm and less than 2000 nm.

Here, the thickness of the organic barrier layer 14 is referred to as the thickness of the flat portion. The liquid film of the photocurable resin for forming the organic barrier layer 14 has a flat (horizontal) surface, and when the substrate has a concave portion, the thickness of the liquid film in this portion becomes large. Further, since the liquid film is curved by surface tension (including capillary phenomenon), the thickness of the liquid film around the convex portion is increased. Such a locally increased thickness portion may exceed 500 nm.

The thickness of the composite laminate 10S is preferably greater than 400nm and less than 2 μm, more preferably greater than 400nm and less than 1.5 μm.

The TFE structure 10 may also form an inorganic insulating layer and/or an organic insulating layer below the composite laminate 10S, or above the composite laminate 10S, or between two composite laminates 10S. In this case, the thickness of the inorganic insulating layer is preferably larger than 400nm and smaller than 1500nm, for example. When the thickness of the inorganic insulating layer is less than 400nm, for example, small particles having a diameter of less than about 0.5 μm are present, and thus the barrier property may be lowered. When the thickness of the inorganic insulating layer is more than 1500nm, the barrier property is saturated, and the film stress increases, as a result, the substrate is warped.

The thickness of the organic insulating layer is preferably greater than 5 μm and less than 20 μm, for example, when it is formed by a general inkjet method. In the ink-jet method, it is difficult to form a uniform organic insulating layer having a thickness of less than 5 μm. On the other hand, when the thickness of the organic insulating layer exceeds 20 μm, the manufacturing cost becomes high because the consumption amount of the expensive material increases. Alternatively, a structure (dam) for blocking an organic material provided by an ink-jet method at a predetermined position needs to be made high, so that the manufacturing process also becomes complicated.

Next, the structure of the OLED display device according to the embodiment of the present invention will be described in further detail with reference to fig. 2 to 4. Hereinafter, the TFE structure 10 is described as being formed by one composite laminate 10S.

First, refer to fig. 2. Fig. 2 is a plan view schematically showing the structure (under the TFE structure 10) of the OLED display device 100 according to the embodiment of the present invention.

The circuit 2 formed on the substrate 1 includes a plurality of TFTs (not shown), a plurality of gate bus lines (not shown) and a plurality of source bus lines (not shown) each connected to any one of the plurality of TFTs (not shown). The circuit 2 may also be a well known circuit for driving a plurality of OLEDs 3. The plurality of OLEDs 3 are connected to any one of the plurality of TFTs included in the circuit 2. The OLED3 may also be a well-known OLED.

The circuit 2 further includes a plurality of terminals 34 and a plurality of lead-out wirings 32, the plurality of terminals 34 are disposed in a peripheral region R2 outside an active region (a region surrounded by a dotted line in fig. 2) R1 in which the plurality of OLEDs 3 are disposed, and the plurality of lead-out wirings 32 are connected to the plurality of terminals 34 and any one of the plurality of gate buses or the plurality of source buses. The circuit 2 including the plurality of TFTs, the plurality of gate bus lines, the plurality of source bus lines, the plurality of lead lines 32, and the plurality of terminals 34 is collectively referred to as a driving circuit layer 2. In the driver circuit layer 2, a portion formed in the active region R1 is referred to as a driver circuit layer 2A.

In fig. 2, although only the lead lines 32 and/or the terminals 34 are illustrated as the components of the drive circuit layer 2, the drive circuit layer 2 includes not only the conductive layer including the lead lines 32 and the terminals 34 but also one or more conductive layers, one or more insulating layers, and one or more semiconductor layers. The configuration of the conductive layer, the insulating layer, and the semiconductor layer included in the driver circuit layer 2 can be changed, for example, by the TFT structure illustrated in fig. 7(a) and (b) described later. Further, an insulating film (base film) may be formed as a base film of the driver circuit layer 2 on the substrate 1.

The TFE structure 10 (composite laminate 10S) is formed so as to protect the active region R1. For example, the first inorganic barrier layer 12 and the second inorganic barrier layer 16 are SiN_xA layer is selectively formed in a predetermined region so as to cover the active region R1 by a plasma CVD method using a mask. Herein, the firstThe inorganic barrier layer 12 and the second inorganic barrier layer 16 are selectively formed on the active region R1 and on the active region R1 side portions of the plurality of lead lines 32, independently of each other. From the viewpoint of reliability, the second inorganic barrier layer 16 is the same as (has the same outer edge as) the first inorganic barrier layer 12, and is preferably formed so as to cover the entire first inorganic barrier layer 12. The periphery of the active region R1 is surrounded by an inorganic barrier junction in direct contact with the first inorganic barrier 12 and the second inorganic barrier 16.

The organic barrier layer 14 can be formed by the method described in patent document 2 or 3, for example. For example, in the container, a vapor or mist of an organic material (for example, acrylic monomer) is supplied to the element substrate maintained at a temperature equal to or lower than room temperature, and condensed on the element substrate, and the organic material in a liquid state is not uniform at a boundary portion between the side surface of the convex portion and the flat portion of the first inorganic barrier layer 12 due to capillary phenomenon or surface tension. Then, for example, the organic material is irradiated with ultraviolet rays, whereby a solid portion of the organic barrier layer (for example, an acrylic resin layer) 14 is formed at the boundary portion around the convex portion. The organic barrier layer 14 formed by this method does not actually have a solid portion at the flat portion. As for the method of forming the organic barrier layer, the disclosures of patent documents 2 and 3 are incorporated into the present specification by reference.

The organic barrier layer 14 can also be formed by adjusting the initial thickness of the resin layer formed using the film formation apparatus 200 (for example, to less than 100nm) and/or by subjecting the temporarily formed resin layer to ashing treatment, as will be described later. For example, the ashing apparatus is formed by using N₂O、O₂And O₃Plasma ashing of at least one gas of (a).

Next, fig. 3 (a) and 3 (b) are referred to. Fig. 3 (a) is a plan view schematically showing the structure of the OLED display device 100A according to the embodiment of the present invention (above the TFE structure 10). Fig. 3 (B) is a plan view schematically showing the structure of the OLED display device 100B according to the embodiment of the present invention (above the TFE structure 10).

The OLED display device 100A shown in fig. 3 (a) has an organic planarization layer 42A and a touch sensing layer 50 on the TFE structure 10, the organic planarization layer 42A is formed of a photosensitive resin, and the touch sensing layer 50 is disposed on the organic planarization layer 42A. Further, an inorganic insulating layer (the inorganic insulating layer 44 of fig. 1) may also be provided between the organic planarization layer 42A and the touch sensing layer 50. The organic planarizing layer 42A is formed only in a predetermined region on the element substrate, and is formed so that the terminal 34 and the lead line 32 in the vicinity of the terminal 34 are exposed. The organic planarization layer 42A may be formed to cover at least the TFE structure 10. The organic planarization layer 42A preferably covers at least the entire active region R1 and is formed in a wider range than the touch sensing layer 50.

For example, the organic planarization layer 42A may be formed as follows.

A liquid containing a negative photosensitive resin is applied only to a predetermined region on an element substrate on which the TFE structure 10 is formed, and then the entire photosensitive resin on the element substrate is irradiated with light. The solvent is removed by heating (prebaking) before the light irradiation as necessary. After the light irradiation, the photosensitive resin may be further cured by heating. The step of applying the liquid containing the photosensitive resin can be performed by a known printing method (for example, an ink jet method and a screen printing method). This method does not require a photomask and also does not require development of the photosensitive resin after exposure.

Alternatively, a liquid containing a negative photosensitive resin is applied to the entire surface of the element substrate on which the TFE structure 10 is formed, and the photosensitive resin present in a predetermined region on the element substrate is selectively irradiated with light. In addition, a liquid containing a positive photosensitive resin is applied to the entire surface on the element substrate forming the TFE structure 10, and light is selectively irradiated to the photosensitive resin present in a region other than the prescribed region on the element substrate. After that, the photosensitive resin is brought into contact with a developer, and the organic planarizing layer 42A can be formed only in a predetermined region by development.

The OLED display device 100B of fig. 3 (B) has an organic planarization layer 42B and a touch sensing layer 50 on the TFE structure 10, the organic planarization layer 42B is formed of a photosensitive resin, and the touch sensing layer 50 is disposed on the organic planarization layer 42B. The OLED display device 100B is different from the OLED display device 100A in that the organic planarization layer 42B covers the entire element substrate. Further, an inorganic insulating layer (the inorganic insulating layer 44 of fig. 1) may also be provided between the organic planarization layer 42B and the touch sensing layer 50.

For example, the organic planarization layer 42B may be formed as follows.

A liquid containing a negative or positive photosensitive resin is applied to the entire surface on the element substrate forming the TFE structure 10, exposed using a photomask, and developed to obtain an organic planarizing layer 42B having an opening 42a exposing the terminal 34. Further, if the external board first connects the terminals 34, the opening 42a does not need to be formed, and therefore, a photomask does not need to be used.

The thickness of the organic planarizing layers 42A, 42B is preferably not more than 15 μm. When it exceeds 15 μm, the flexibility may be lowered. The thickness of the organic planarizing layers 42A and 42B is preferably, for example, greater than 3 μm from the viewpoint of the function of planarizing in the presence of particles.

The photosensitive resin is preferably, for example, a silicone resin (here, a silicone rubber or a silicone elastomer is widely used). When the organic planarizing layer is formed using a silicone resin, the transmittance for light of 350nm can be made greater than 80%. Acrylic resins may also be used instead of silicone resins. The acrylic resin can also obtain an organic planarization layer having high transmittance of visible light. However, in order to have a transmittance of more than 80% for light of 350nm, it is preferable to use a silicone resin. For example, KER-2500, manufactured by shin-Etsu chemical Co., Ltd., can be used as the silicone resin.

From the viewpoint of flexibility (bendability) of the OLED display device, it is preferable that the elastic modulus of the photosensitive resin at 0 ℃ is not more than 400 MPa. For example, in the evaluation using a U-shaped bending tester for a planar body manufactured by soup-and-shallow system machines corporation, the bending test was able to withstand 1 ten thousand times of bending operations. Specifically, the bent portion was bent in a U-shape at 25 ℃ so that the radius of the bent portion became 5mm, and the operation was performed at 1HzThe frequency was not observed to cause cracks even after ten thousand bending operations were performed, and 10 was obtained even in the WVTR evaluation using Ca (calcium)^-5g/m²The value of day table. In addition, it also has an effect of moderating external force applied to the OLED layer of the OLED display device.

As described above, since TFE10 has excellent barrier properties, exposure and development processes can be performed using a photosensitive resin for an element substrate on which TFE10 is formed. Since the OLED layer is easily deteriorated in contact with chemicals, when the barrier property of TFE10 is lowered, the OLED layer is deteriorated in the developing process.

Next, fig. 4 (a) to (b) are referred to. Fig. 4 (a) to (C) are schematic cross-sectional views of the OLED display device 100A shown in fig. 3, fig. 4 (a) is a cross-sectional view taken along line 4A-4A ' in fig. 3, (B) in fig. 4 is a cross-sectional view taken along line 4B-4B ' in fig. 3, and (C) in fig. 4 is a cross-sectional view taken along line 4C-4C ' in fig. 3. Fig. 4 (d) is a cross-sectional view of the OLED display device 100C of the comparative example, corresponding to a cross-sectional view taken along line 4B-4B' in fig. 3.

Fig. 4 (a) is a cross-sectional view taken along line 4A-4A' in fig. 3, showing a portion including the particle P. The particles P are fine dust generated in the manufacturing process of the OLED display device, and are, for example, fine fragments of glass, metal particles, or organic particles. When the mask evaporation method is used, particles are particularly easily generated.

As shown in fig. 4 (a), the organic barrier layer (solid portion) 14 may be formed only around the particles P. This is because the acrylic monomer added after the formation of the first inorganic barrier layer 12 is condensed and unevenly distributed around the surface (taper angle θ is larger than 90 °) of the first inorganic barrier layer 12a on the particles P. The opening (non-solid portion) of the organic barrier layer 14 is formed on the flat portion of the first inorganic barrier layer 12.

When particles (e.g., greater than about 1 μm in diameter) P are present, cracks (defects) 12c may form on the first inorganic barrier layer 12. This is conceivably because SiN grows from the surface of the particle P_xLayer 12a with SiN grown from a flat portion of the surface of OLED3_xLayer 12b conflicts. When storingIn such a slit 12c, the barrier property of the TFE structure 10 is reduced.

In the TFE structure 10 of the OLED display device 100, as shown in fig. 4 (a), the organic barrier layer 14 is formed so as to fill the slits 12c of the first inorganic barrier layer 12, and the surface (concave shape) of the organic barrier layer 14 is continuously and smoothly connected to 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. As described later, the organic barrier layer 14 is formed by curing a liquid photocurable resin, and therefore, a concave surface is formed by surface tension. In this case, the photocurable resin exhibits good wettability with respect to the first inorganic barrier layer 12. If the first inorganic barrier layer 12 of the photocurable resin exhibits poor wettability, it becomes convex on the contrary.

The organic barrier layer (solid portion) 14 having a concave surface does not form defects on the first inorganic barrier layer 12a on the particles P and the second inorganic barrier layer 16 formed on the organic barrier layer 14, and thus a fine film is formed. In this manner, the organic barrier layer 14 can maintain the barrier property of the TFE structure 10 (composite laminated body 10S) even if the particles P are present.

The composite laminate 10S has the relatively flexible organic barrier layer (solid portion) 14 around the particles P, and the continuous second inorganic barrier layer 16 on the particles P, so that cracks are suppressed from occurring from the particles P even when the composite laminate is bent, and therefore, the barrier property is suppressed from being lowered by bending, and the composite laminate has excellent bending resistance.

As shown in fig. 4B, in a region close to the active region R1 (a cross section taken along line 4B-B' in fig. 3 a), the TFE structure 10 and the organic planarization layer 42A are formed on the lead line 32.

As shown in fig. 4 (c), the terminals 34 are exposed and used for electrical connection with an external circuit (FPC).

The region including the portion shown in fig. 4 (b) may form an organic barrier layer (solid portion) in the process of forming the organic barrier layer 14 of the TFE structure 10. For example, as shown in fig. 4 (d), the OLED display device 100C of the comparative example has the TFE structure 10C, when the side surface of the sectional shape parallel to the line width direction of the lead-out wiring 32 has the taper angle θ larger than 90 °, the organic barrier layer 14C may be formed along the side surface of the lead-out wiring 32. In contrast, in the OLED display device 100A according to the embodiment, the taper angle θ of the side surface of the cross-sectional shape of the lead line 32 and the terminal 34 is set to be less than 90 °, and the photocurable resin is not uneven. Therefore, the organic barrier layer (solid portion) is not formed along the side surfaces of the lead line 32 and the terminal 34.

When the taper angle θ of the side surface is larger than 90 °, in the method for forming an organic barrier layer described in patent document 2 or 3, the vapor or mist of the organic material (for example, acrylic monomer) condenses along the boundary between the side surface and the flat surface (which becomes an angle smaller than 90 °), and the organic barrier layer (solid portion) is formed. In this way, for example, the organic barrier layer (solid portion) formed along the lead line becomes a path for guiding water vapor in the air into the active region.

As shown in fig. 4 (b), in the OLED display device 100A according to the embodiment of the present invention, the taper angle of the side surfaces of the lead line 32 and the first inorganic barrier layer 12 is smaller than 90 °, and the organic barrier layer 14 is not formed along these side surfaces. Therefore, moisture in the air does not reach the active region R1 through the organic barrier layer (solid portion) 14, and excellent moisture resistance reliability can be obtained. Here, although the case where the taper angle of the lead-out wiring is less than 90 ° is exemplified, the taper angle of at least the side surface of the first inorganic barrier layer 12 constituting the surface immediately below the organic barrier layer 14 may be less than 90 °.

In addition, the taper angle of the side surface is in a range of more than 70 ° and less than 90 °, and the organic barrier layer (solid portion) 14 may be formed along the side surface. Of course, if the ashing treatment is performed, the uneven resin can be removed along the inclined side surface, but the time required for the ashing treatment is long. For example, a long time of ashing treatment is also required after removing the resin formed on the flat surface. Alternatively, the organic barrier layer (solid portion) formed around the particles P is excessively ashed (removed), which results in a problem that the effect of forming the organic barrier layer cannot be sufficiently exhibited. In order to suppress or prevent this, the taper angle θ of the first inorganic barrier layer 12 is preferably set to less than 70 °, and more preferably to less than 60 °.

The touch sensing layer 50 having the OLED display device 100 according to the embodiment of the present invention may be a known touch sensing layer. For example, the touch sensor layer may be a resistive film type or a projected capacitive touch sensor layer. Referring to fig. 5 and 6, the structure of the touch sensing layer 50A and the touch sensing layer 50B applied to the OLED display device 100 will be described.

Fig. 5 (a) is a schematic plan view of the touch sensor layer 50A, and fig. 5 (b) is a plan view of the touch sensor layer 50A. The touch sensing layer 50A is formed on the inorganic insulating layer 44 formed on the organic planarization layer 42.

The touch sensing layer 50A has a plurality of X electrodes 52A and a plurality of Y electrodes 54A, the plurality of X electrodes 52A extending along the X direction, and the plurality of Y electrodes 54A extending along the Y direction perpendicular to the X direction. Any one of the X electrode 52A and the Y electrode 54A is formed of a metal mesh. The minimum unit of the metal mesh is, for example, a square of 35 μm × 35 μm, and a plurality of these are collected to form, for example, a unit electrode of a square of 3mm × 3mm, and the unit electrodes are connected to the X direction or the Y direction by wirings, respectively. The portion where the wiring crosses is, for example, an inorganic insulating layer (SiN)_xLayers) are insulated from each other (not shown). The metal mesh has, for example, a laminated structure of a Ti layer and an AI layer, or a laminated structure of a Ti layer/AI layer/Ti layer.

Fig. 6 (a) is a schematic plan view of the touch sensor layer 50B, and fig. 6 (B) is a plan view of the touch sensor layer 50B. The touch sensing layer 50B is formed on the inorganic insulating layer 44 formed on the organic planarization layer 42. Any one of the X electrode 52B and the Y electrode 54B having the touch sensing layer 50B is formed of a transparent conductive layer (e.g., ITO layer) and an inorganic insulating layer (e.g., SiN layer)_xLayers) are insulated from each other. The touch sensing layer 50A is more advantageous from the viewpoint of transmittance of light.

In addition, in the flexible OLED display device, for example, a polyimide film is formed on a support substrate (e.g., a glass substrate), and the polyimide film on the support substrate is formed as the substrate 1. Here, an OLED display device having the touch sensing layer 50A or 50B is exemplified, and after the touch sensing layer 50A or 50B is formed, a polyimide film can be detached from a supporting substrate to obtain.

Next, an example of a TFT to be used in an OLED display device and an example of forming a lead line and a terminal using a gate metal layer and a source metal layer in manufacturing the TFT will be described with reference to fig. 7 and 8.

High-definition small-to-medium-sized OLED display devices are suitable for TFTs or oxide TFTs (for example, 4-membered (In-Ga-Zn-O) oxides including In (indium), Ga (gallium), Zn (zinc), and O (oxygen)) using high-mobility, low-temperature polycrystalline silicon (abbreviated as "TPS"). The LTPS-TFT and In-Ga-Zn-O TFT structures and manufacturing methods are well known, and therefore, the following description is made briefly.

FIG. 7(a) shows LTPS-TFT2_PSchematic cross-sectional view of T, TFT2_PT may comprise circuit 2 of OLED display device 100. LTPS-TFT2_PT is a TFT of a top gate type.

TFT2_PT is a base film 2 on a substrate (e.g., polyimide film) 1_PP is formed on the substrate. Although the above description is omitted, it is preferable to form a base film formed of an inorganic insulator on the substrate 1.

TFT2_PT is formed on the base film 2_P polysilicon layer 2 on p_Pse formed on the polysilicon layer 2_P Gate insulating layer 2 on se_Pgi. Formed on the gate insulating layer 2_P gi gate electrode 2_Pg. Formed on the gate electrode 2_Pg interlayer insulating layer 2_Pi. A source electrode 2 formed on the interlayer insulating layer 2Pi_Pss and drain electrode 2_PAnd sd. Source electrode 2_Pss and drain electrode 2_Psd is formed in the interlayer insulating layer 2_Pi and a gate insulating layer 2_PIn contact holes of gi, respectively with the polysilicon layer 2_PThe source and drain regions of se are in contact.

Gate electrode 2_Pg the same as the gate bus line, including a gate metal layer, a source electrode 2_Pss and drain electrode 2_Psd comprises a source metal layer in common with the source bus. Use ofThe gate metal layer and the source metal layer are formed with lead lines and terminals (see fig. 8 and described later).

TFT2_PT is made, for example, in the following manner.

For example, a polyimide film having a thickness of 15 μm is prepared as the substrate 1.

Base film 2 by plasma CVD method_Pp(SiO₂Film formation: 250nm/SiN_xFilm formation:

50nm/SiO₂film formation: 500nm (upper layer/middle layer/lower layer)) and an a-Si film (40 nm).

Dehydrogenation treatment of the a-Si film (e.g., annealing at 450 ℃ for 180 minutes) is performed.

The a-Si film is polycide using an Excimer Laser Annealing (ELA) method.

The active layer (semiconductor island) is formed by patterning the a-Si film in the wavelength conversion process.

Forming a gate insulating film (SiO) by plasma CVD₂Film formation: 50nm) was formed.

Doping (B +) is performed in the channel region of the active layer.

A gate metal (Mo: 250nm) was formed by sputtering, and patterned (gate electrode 2 was formed) in a wavelength conversion step (including a dry etching step)_Pg, gate bus lines, etc.).

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

Activation annealing (e.g., annealing at 450 ℃ for 45 minutes) is performed. Thus obtaining a polysilicon layer 2_Pse。

Interlayer insulating film (e.g. SiO) by plasma CVD₂Film formation: 300nm/SiN_xFilm formation: 300nm (upper layer/lower side)).

Contact holes are formed in the gate insulating film and the interlayer insulating film by a dry etching method. Thus, an interlayer insulating layer 2 was obtained_Pi and a gate insulating layer 2_Pgi。

A source metal (Ti film: 100nm/Al film: 300nm/Ti film: 30nm) was formed by sputtering, and patterned (source electrode 2 was formed) in a wavelength conversion step (including a dry etching step)_Pss, drain electrode 2_Psd and gate bus, etc.).

FIG. 7 (b) is an In-Ga-Zn-O system TFT2_OSchematic cross-sectional view of T, TFT2_OT may comprise circuit 2 of OLED display device 100. TFT2_OT is a TFT of a top gate type.

TFT2_OT is a base film 2 on a substrate (e.g., polyimide film) 1_Op is formed on the substrate. TFT2_OT is formed on the base film 2_O Gate electrode 2 on p_Og. Formed on the gate electrode 2_Og upper gate insulating layer 2_Ogi. Formed on the gate insulating layer 2_Ogi oxide semiconductor layer 2_Ose in the oxide semiconductor layer 2_OA source electrode 2 connected to the source region and the drain region of se_Oss and drain electrode 2_OAnd sd. Source electrode 2_Oss and drain electrode 2_Osd is covered with an interlayer insulating layer 2 Oi.

Gate electrode 2_Og is the same as the gate bus and comprises a gate metal layer, a source electrode 2_Oss and drain electrode 2_Osd is the same as the source bus and includes a source metal layer. Lead wirings and terminals are formed using the gate metal layer and the source metal layer, and may have a structure described later with reference to fig. 8.

TFT2_OT is made, for example, in the following manner.

For example, a polyimide film having a thickness of 15 μm is prepared as the substrate 1.

The base film 2Op (SiO) was formed by a plasma CVD method₂Film formation: 250nm/SiN_xFilm formation: 50nm/SiO₂Film formation: 500nm (upper layer/middle layer/lower layer)).

A gate metal (Cu film: 300nm/Ti film: 30nm (upper layer/lower layer)) was formed by sputtering, and patterned in a wavelength conversion step (including a dry etching step) (gate electrode 2Og, gate bus line, and the like were formed).

Forming a gate insulating film (SiO) by plasma CVD₂Film formation: 300nm/SiN_xFilm formation: 300nm (upper layer/lower layer)).

An oxide semiconductor film (In-Ga-Zn-O semiconductor film: 100nm) was formed by a sputtering method, and an active layer (semiconductor island) was formed by patterning In a wavelength conversion step (including a wet etching method).

A source metal (Ti film: 100nm/Al film: 300nm/Ti film: 30nm (upper layer/middle layer/lower layer)) was formed by sputtering, and patterned (source electrode 2 was formed) in a wavelength conversion step (including a dry etching step)_Oss, drain electrode 2_Osd and gate bus, etc.).

Activation annealing (e.g., annealing at 300 ℃ for 120 minutes) is performed. Thus, an oxide semiconductor layer 2 was obtained_Ose。

Thereafter, the interlayer insulating film 2Oi (e.g., SiO) is formed by plasma CVD₂Film formation: 300nm/SiN_xFilm formation: 300nm (upper layer/lower layer)) was formed as a protective film.

Next, the structure of another OLED display device according to the embodiment of the present invention will be described with reference to (a) and (b) of fig. 8. The circuit (back plate) 2 of the OLED display device has a TFT2 shown in fig. 7(a)_PT or TFT2 shown in FIG. 7 (b)_OT, fabrication TFT2_PT or TFT2_OThe lead line 32A and the terminal 34A are formed by the gate metal layer and the source metal layer at time T. Fig. 8 (a) and (b) correspond to fig. 4 (b) and (c), respectively, and reference numerals assigned to corresponding components are denoted by "a". The TFE structure 10A in fig. 8 (a) is covered with an organic planarizing layer (not shown). Note that the base film 2p in fig. 8, the base film 2Pp in fig. 7(a), and the base film 2 in fig. 7 (b)_Op corresponds to the gate insulating layer 2gi in fig. 8 and the gate insulating layer 2 in (a) of fig. 7_Pgi and the gate insulating layer 2 in fig. 7 (b)_Ogi corresponds to the interlayer insulating layer 2i in fig. 8 and the interlayer insulating layer 2Pi in fig. 7(a) and the interlayer insulating layer 2 in fig. 7 (b), respectively_Oi corresponds to.

As shown in fig. 8 (a) and (b), the gate metal layer 2g and the source metal layer 2s are formed on a base film 2p formed on the substrate 1. Although omitted in fig. 4, it is preferable to form a base film 2p formed of an inorganic insulator on the substrate 1.

As shown in fig. 8 (a) and (b), the lead line 32A and the terminal 34A are formed as a laminate between the gate metal layer 2g and the source metal layer 2 s. The portions of the lead line 32 and the terminal 34A formed in the gate metal layer 2g have, for example, the same cross-sectional shape as the gate bus line, and the portions of the lead line 32 and the terminal 34A formed in the source metal layer 2s have, for example, the same cross-sectional shape as the source bus line. For example, in the case of a 5.7 type display device of 500pii, the line width of the portion formed on the gate metal layer 2g is, for example, 10 μm, the adjacent pitch is 16 μm (L/S — 10/16), the line width of the portion formed on the source metal layer 2S is, for example, 16 μm, and the adjacent pitch is 10 μm (L/S — 16/10). Any of the taper angles θ is less than 90 °, preferably less than 70 °, and more preferably less than 60 °.

Next, a film formation apparatus 200 for forming an organic barrier layer and a film formation method thereof will be described with reference to (a) and (b) of fig. 9. Fig. 9 (a) and (b) are schematic diagrams showing the configuration of the film formation apparatus 200, fig. 9 (a) shows a state of the film formation apparatus 200 in a step of condensing a photocurable resin on a first inorganic barrier layer in a container containing the photocurable resin in a vapor or mist form, and fig. 9 (b) shows a state of the film formation apparatus 200 in a step of curing the photocurable resin by light having photosensitivity at the time of irradiation.

The film forming apparatus 200 includes a container 210 and a partition wall 234, and the partition wall 234 divides the interior of the container 210 into two spaces.

In one space partitioned by a partition wall in the container 210, a mounting table 212 and a shower plate 220 are disposed. Ultraviolet irradiation device 230 is disposed in the other space partitioned by partition wall 234. The container 210 controls the internal space to a predetermined pressure (vacuum) and temperature. The mounting table 212 includes an upper surface for accommodating the element substrate 20 including the plurality of OLEDs 3 on which the first inorganic barrier layer is formed, and is capable of cooling the upper surface to-20 ℃.

The shower plate 220 is disposed so as to form a gap 224 with the partition wall, and has a plurality of through holes 222. The vertical dimension of the gap portion 224 may be, for example, greater than 100nm and less than 100 nm. The acrylic monomer (vapor or mist) supplied to the gap portion 224 is supplied from the plurality of through holes 222 of the shower plate 220 to the space on the mounting table 212 side in the container 210. The acrylic monomer is heated as necessary. The vapor or mist of the acrylic monomer 26p adheres to or contacts the first inorganic barrier layer of the element substrate 20. Acrylic monomer 26 is supplied from container 202 into container 210 at a prescribed flow rate. The container 202 is supplied with the acrylic monomer 26 through the pipe 206, and is supplied with nitrogen gas from the pipe 204. The flow of acrylic monomer to vessel 202 is controlled by 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.

The ultraviolet irradiation device 230 has an ultraviolet light source and optional optical elements. The ultraviolet light source may be, for example, an ultraviolet lamp (for example, a mercury lamp or the like (including high pressure and ultrahigh pressure), a mercury-xenon lamp, or a metal halide lamp), or an ultraviolet light-emitting semiconductor element such as an ultraviolet LED or an ultraviolet semiconductor sensor. Examples of the optical element include a mirror, a prism, an optical fiber, a diffraction element, a spatial light modulation element, and a hologram element. A plurality of ultraviolet light sources may be used depending on the type and size of the ultraviolet light source.

When the ultraviolet irradiation device 230 is disposed at a predetermined position, light having a predetermined wavelength and intensity is emitted toward the upper surface of the stage 212. The partition wall 234 and the shower plate 220 are preferably made of a material having a high ultraviolet transmission path, for example, quartz.

The organic barrier layer 14 can be formed as follows using the film formation apparatus 200. Here, an example of using an acrylic monomer as the photocurable resin will be described.

Acrylic acid 26p is provided into container 210. The element substrate 20 is cooled to, for example, -15 ℃ on the container 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 made uneven around the convex portion having the first inorganic barrier layer 12. Alternatively, the conditions are controlled so that the acrylic acid condensed on the first inorganic barrier layer 12 forms a liquid film.

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 connected to the convex portion of the first inorganic barrier layer 12 can be controlled. For example, since the viscosity and the surface tension depend on the temperature, the viscosity and the surface tension 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 in contact with the convex portion of the first inorganic barrier layer 12D of the liquid film and the conditions for performing the ashing treatment thereafter.

Next, the acrylic monomer on the first inorganic barrier layer 12 is cured by irradiating ultraviolet rays 232, typically, on the entire upper surface of the element substrate 20 using an ultraviolet irradiation apparatus 230. As the ultraviolet light source, for example, a high pressure mercury lamp having a main peak of 365nm was used, and the irradiation was performed at an ultraviolet intensity of, for example, 12mW/cm2 for about 10 seconds.

The organic barrier layer 14 composed of an acrylic resin is formed as follows. The takt time of the step of forming the organic barrier layer 14 is, for example, about less than 30 seconds, and productivity is very high.

The organic barrier layer 14 may be formed around the convex portion by curing the liquid film-like photocurable resin and then subjecting the cured resin to ashing treatment. In addition, when the organic barrier layer 14 is formed by curing the uneven photo-valley chemical resin, ashing treatment may be performed. The ashing treatment can improve the connectivity between the organic barrier layer 14 and the second inorganic barrier layer 16. That is, the ashing treatment is not only for removing an unnecessary portion of the organic barrier layer once formed, but also for surface modification (hydrophilization) of the organic barrier layer 14.

The ashing treatment can be performed using a known plasma ashing apparatus, a photoexcitation ashing apparatus, and a UV ozone ashing apparatus. For example, N may be used₂O、O₂And O₃Plasma ashing or a combination of the above with further ultraviolet irradiation. SiN as the first inorganic barrier layer 12 and the second inorganic barrier layer 16 was formed by a CVD method_xWhen a film is formed, N is used₂O is used as the raw material gas, so that N is used₂The ashing may be performed by using a single ashing apparatus.

When ashing is performed, the surface of the organic barrier layer 14 is oxidized and modified to be hydrophilic. The surface of the organic barrier layer 14 is cut to be substantially uniform, and at the same time, extremely fine irregularities are formed, thereby increasing the surface area. The surface area increasing effect when ashing is performed is greater with respect to the surface of the organic barrier layer 14 as compared to the inorganic material, i.e., the first inorganic barrier layer 12. Therefore, hydrophilicity from the surface of the organic barrier layer 14 is modified and the surface area is increased, so that close contact with the second inorganic barrier layer 16 is improved.

Thereafter, the substrate is transported to a CVD container for forming the second inorganic barrier layer 16, for example, the second inorganic barrier layer 16 is formed under the same conditions as the first inorganic barrier layer 12. Since the second inorganic barrier layer 16 is formed in the region where the first inorganic barrier layer 12 is formed, the non-solid portion of the organic barrier layer 14 is formed with an inorganic barrier layer junction that is in direct contact with the first inorganic barrier layer 12 and the second inorganic barrier layer 16. Therefore, as described above, the organic barrier layer can control and prevent the water vapor in the air from reaching the active region.

The first inorganic barrier layer 12 and the second inorganic barrier layer 16 are formed, for example, as follows. In the use of SiH₄And N₂In the O gas plasma CVD method, for example, an inorganic barrier layer having a thickness of 400nm can be formed at a film formation rate of 400nm/min while controlling the temperature of the substrate (OLED3) to be formed to 80 ℃ or lower. The inorganic barrier layer thus obtained had a curvature of 1.84 and a visible light transmittance of 90% at 400nm (thickness of 400 nm). In addition, the absolute value of the film stress was 20 MPa.

In addition, other than SiN_xIn addition to the layer, SiO can also be used₂、SiO_xN_y(x>y) layer, SiN_xO_y(x>y) layer, Al₂O₃Layers, etc. as inorganic barrier layers. The photocurable resin includes, for example, a vinyl group-containing monomer. Among them, it is suitably used for acrylic monomers. The acrylic monomer may be mixed with a photopolymerization initiator as required. Various known acrylic monomers can also be used. It is also possible to mix a plurality of acrylic monomers. For example, it is also possible to mix difunctional monomers withA polyfunctional monomer having more than a trifunctional monomer. Further, oligomers may be mixed. An ultraviolet-curable silicone resin may also be used as the photocurable resin. Silicone resins (including silicone gels) are excellent in visible light transmittance and weather resistance, and are characterized by not yellowing even after long-term use. A photocurable resin that is cured by irradiation with visible light may also be used. The viscosity of the photocurable resin before curing at room temperature (for example, 20 ℃) is preferably not more than 10PA · S, and more preferably 1 to 100mPa · S. When the viscosity becomes high, it may be difficult to form a thin liquid film having a thickness of less than 50 nm.

In the above, the embodiments of the OLED display device having a flexible substrate and the method of manufacturing the same have been described, but the embodiments of the present invention are merely exemplary and not restrictive, and can be widely applied to an organic EL apparatus (for example, an organic EL lighting device) having an organic EL element formed with a substrate (for example, a glass substrate) having no flexibility and a thin film encapsulation structure formed on the organic EL element.

Industrial applicability

Embodiments of the present invention are used for an organic EL device and a method of manufacturing the same. Embodiments of the present invention are particularly applicable to a flexible organic EL display device and a method of manufacturing the same.

Description of the reference numerals

1 substrate (Flexible substrate)

2 Circuit (Driving circuit or backboard circuit)

3 organic EL element

4 polarizing plate

10 film packaging structure (TFE structure)

12 first inorganic Barrier (SiN)_xLayer)

14 organic Barrier layer (acrylic resin layer)

16 second inorganic Barrier (SiN)_xLayer)

20 element substrate

26 acrylic acid monomer

Vapor of 26P acrylic monomer or atomized acrylic monomer

100. 100A organic EL display device.