JP2005011573A - Organic el device, its manufacturing method, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL device composed by adhering the side of a negative electrode formed of an inorganic material to the side of a luminescent layer formed of an organic material, thereby preventing the deterioration of the luminescent layer due to oxygen or moisture to improve durability; to provide its manufacturing method and an electronic apparatus equipped with it. <P>SOLUTION: This organic EL device is composed by arranging, on a substrate, a first electrode 23, a function layer formed of an organic material and having at least a luminescent layer 60, and a second electrode 50 in that order. The luminescent layer 60 is formed in pixel regions surrounded by barrier ribs 221 formed of an organic material. A closely-attached layer 65 formed of an organic silicon compound or an organic titanium compound is formed on the surface(s) of barrier ribs 221 and/or the function layer. The second electrode 50 formed of an inorganic material is formed on the surface of the adhered layer 65. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an organic EL device, a manufacturing method thereof, and an electronic apparatus.
[0002]
[Prior art]
Conventionally, an electro-optical device such as an organic electroluminescence (hereinafter abbreviated as organic EL) display device includes an anode, a hole injection layer, a light emitting layer made of an organic electro-optical material having EL characteristics, and an electron injection layer on a substrate. An element structure in which a cathode including the like is laminated is known. In the organic EL element that constitutes such an organic EL device, there is a problem that the life of the light emitting element is shortened due to the deterioration of the material forming the light emitting layer and the electron injection layer due to the intrusion of oxygen and moisture in the atmosphere.
[0003]
Therefore, in order to prevent the penetration of oxygen and moisture from the external environment, a sealing structure is usually used in which the cathode is covered with a glass plate or a metal plate so as to cover the cathode and bonded with a sealing material such as a resin. Since the material also has a large amount of oxygen and moisture permeation, it is necessary to install a getter material that absorbs moisture at a high speed so as not to reach the element. In addition, organic materials such as a light emitting material and a partition material that separates pixels have a large volume expansion in a high temperature environment due to heat generation during external environment or energization, and the generated stress is an interface with an inorganic material such as a second electrode. As a result, moisture or the like enters, and as a result, the durability of the light-emitting element decreases.
[0004]
As a result of examining the lifetime reduction of the light-emitting element due to such oxygen and moisture, the present inventor has improved the adhesion between the light-emitting layer and partition walls, which are organic materials, and the cathode, which is an inorganic material, to increase the temperature. Knowledge to improve the durability of light-emitting elements by preventing moisture and oxygen from entering the light-emitting layer and electron-injecting layer by preventing peeling that occurs in the environment and further preventing damage to the gas barrier layer due to the stress caused by peeling Got.
[0005]
In the organic EL device, as a technique for particularly improving the adhesion between the cathode and the light emitting layer, for example, a cathode electrode (cathode) is provided by laminating an electron injection layer having a high electron injection property and a metal adhesion layer, What comprised this metal contact | adherence layer so that it might join to an organic electroluminescent layer (light emitting layer) is known (for example, refer patent document 1).
In addition, organic protection consisting of hexamethyldisilazane, hexamethyldisiloxane, etc. covering the hole transport layer, the electron transport layer, and the cathode electrode is only for preventing the permeation of oxygen and moisture. The thing which provided the layer and the metal thin film is known (for example, refer patent document 2).
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-162653
[Patent Document 2]
JP 9-270296 A
[0007]
[Problems to be solved by the invention]
However, in the technique provided with the metal adhesion layer, since the adhesion layer is basically a metal and an inorganic material, the adhesion with the light-emitting layer, which is an organic material, is not sufficiently good. There was a problem that sufficient adhesion between the light emitting layer was not obtained.
In addition, as described above, it is known that the durability is improved by simply preventing the permeation of oxygen and moisture, but the organic protective film is not provided between an inorganic material and an organic material. Absent. Therefore, in an organic EL device, a technology for improving the adhesion between an inorganic material and an organic material having different properties has not yet been provided.
[0008]
The present invention has been made in view of the above circumstances, and the object of the present invention is to satisfactorily adhere between the cathode side made of an inorganic material and the light emitting element side made of an organic material, so that even in a high temperature environment. To provide an organic EL device, a manufacturing method thereof, and an electronic apparatus including the same, which have improved durability by preventing entry of oxygen and moisture from the outside environment without causing separation of the interface. .
[0009]
[Means for Solving the Problems]
In order to achieve the above object, an organic EL device according to the present invention includes a first electrode, a functional layer made of an organic material having at least a light emitting layer, and a second electrode arranged in this order on a substrate. The light emitting layer is provided in a pixel region surrounded by a partition made of an organic material, and an adhesion layer made of an organosilicon compound or an organic titanium compound is provided on a surface of the partition and / or the functional layer, and the adhesion layer The second electrode made of an inorganic material is provided on the surface of the substrate.
According to this organic EL device, an adhesion layer made of an organic silicon compound or an organic titanium compound is provided between the partition wall and / or the functional layer made of an organic material and the second electrode made of an inorganic material. Therefore, the organosilicon compound or the organotitanium compound constituting the adhesion layer includes an inorganic group having a silicon (Si) atom or a titanium (Ti) atom and an organic group having a carbon (C) atom. As a result, the partition and / or the functional layer and the second electrode are interposed between the adhesion layers so that the separation does not occur even in a high temperature environment in which volume expansion occurs.
Therefore, the second electrode and the gas barrier layer are not damaged by the stress generated by the peeling of these interfaces, and the penetration of oxygen and moisture is prevented. The improvement of property is obtained.
[0010]
In the organic EL device, the adhesion layer is preferably provided so as to be covered in a wider range so that the partition walls and the functional layer are not exposed. In addition, it is preferable that a gas barrier layer is provided in a wider range so that the second electrode is not exposed.
In this way, by covering the adhesion layer and the second electrode also on the surface and the side surface with the gas barrier layer, the functional layer and the second electrode, which are easily altered by oxygen and moisture, can be applied not only from the surface but also from the side surface. Since it can protect, the deterioration of the light emitting element due to the intrusion of oxygen or moisture can be prevented more reliably.
[0011]
In this organic EL device, the gas barrier layer is preferably an insulating layer made of any one of an inorganic oxide, an inorganic nitride, and an inorganic oxynitride.
In this way, in particular, the second electrode is made of an inorganic material, so that the gas barrier layer also made of an inorganic material adheres well to the second electrode and becomes a dense layer without defects, and therefore This gas barrier layer has better barrier properties against oxygen and moisture.
[0012]
The gas barrier layer may be a silicon compound.
Thus, if the gas barrier layer is formed of a silicon compound that is an inorganic material such as silicon nitride, silicon oxynitride, or silicon oxide, the gas barrier layer is also excellent with respect to the second electrode made of the inorganic material. By being in close contact and becoming a dense layer without defects, the gas barrier layer has better barrier properties against oxygen and moisture. Moreover, since these silicon compounds have transparency, if a transparent second electrode is selected, a top emission structure in which light emission is extracted from the sealing surface can be obtained.
[0013]
The gas barrier layer may be a multilayer film formed by laminating a titanium compound and a silicon compound.
By using a titanium compound that has ultraviolet absorptivity and photocatalytic activity, such as titanium oxide, titanium oxynitride, and strontium titanate, the titanium compound layer functions as an ultraviolet absorbing layer. This improves the light resistance when used outdoors. Further, when the silicon compound layer is formed on the titanium compound layer, the surface of the titanium compound layer is activated by light such as ultraviolet rays generated by the formation, and the photocatalytic activity is exhibited. Then, for example, even if impurities such as organic substances adhere to the surface of the titanium compound layer, the impurities are decomposed and removed by the action of the photocatalyst, whereby the silicon compound is satisfactorily stacked on the titanium compound layer.
[0014]
In the organic EL device, a protective layer is preferably provided on the gas barrier layer.
In this way, the second electrode and functional layer covered with the gas barrier layer can be more reliably protected with the protective layer.
[0015]
In this organic EL device, it is preferable that the protective layer has a buffer function against mechanical shock or has a surface protective function.
If it has a buffer function, the second electrode, the functional layer, and the gas barrier layer can be protected against mechanical impacts from the outside. In addition, as a surface protection function, for example, if it has functions such as pressure resistance, wear resistance, gas barrier property, and ultraviolet blocking property, the functional layer (for example, light emitting layer) and the second electrode are protected by this protective layer. Therefore, the durability of the light emitting element is improved. Furthermore, if the second electrode, the gas barrier layer, and the protective layer are transparent, the protective layer has a light reflection preventing function, so that the light emission characteristics are improved.
[0016]
In the organic EL device, it is preferable that the organosilicon compound serving as the adhesion layer is aminosilane or silazane having a nitrogen atom.
When aminosilane or silazane is used in this manner, functional groups containing nitrogen atoms such as highly reactive amino groups and silazane groups are extremely easy to adhere to the surface of the organic material. The interface between the functional layer and the second electrode made of an inorganic material adheres well even in a high temperature environment.
[0017]
In the organic EL device, the functional layer may include at least one organic carrier injection / transport layer having a carrier injection or transport effect, and the second electrode is an electron on the adhesion layer side. An inorganic electron injection layer having an injection effect may be provided.
In this way, the carrier injection property to the light emitting layer is improved, and the light emission characteristics are improved. In addition, since the electron injection layer is inorganic, the adhesion with the adhesion layer is improved as in the case of the second electrode not provided with the electron injection property.
[0018]
The organic EL device manufacturing method of the present invention is a method for manufacturing an organic EL device in which a first electrode, a functional layer made of an organic material and having at least an organic light emitting layer, and a second electrode are formed in this order on a substrate. A step of providing the light emitting layer in a pixel region surrounded by a partition made of an organic material, and a step of providing an adhesion layer made of an organosilicon compound or an organic titanium compound on the surface of the partition and / or the functional layer. And a step of providing the second electrode made of an inorganic material on the surface of the adhesion layer.
According to this method of manufacturing an organic EL device, an adhesion layer made of an organic silicon compound or an organic titanium compound is provided between the partition wall and / or the functional layer made of an organic material and the second electrode made of an inorganic material. Since the organic silicon compound or the organic titanium compound constituting the adhesion layer includes an inorganic group and an organic group, the partition wall and / or the functional layer and the second layer are provided. Adhesion with the electrode is satisfactorily satisfactorily achieved through the adhesion layer.
Therefore, by preventing the permeation of oxygen and moisture between them, it is possible to prevent the deterioration of the light emitting layer, particularly in the functional layer, and therefore the durability of the obtained organic EL device can be improved.
[0019]
The method for manufacturing the organic EL device preferably includes a step of providing a gas barrier layer on the second electrode.
In this way, even if the second electrode contains a material having a high electron injection property and easily changes in moisture absorption, a decrease in durability can be prevented.
[0020]
Moreover, it is preferable that the adhesion layer, the second electrode, and the gas barrier layer are continuously formed by a vapor deposition method.
In this way, productivity can be improved, for example, by forming each layer by the same vapor deposition method.
[0021]
An electronic apparatus according to the present invention includes the organic EL device or the organic EL device obtained by the manufacturing method.
According to this electronic apparatus, as described above, the organic EL device is provided with the organic EL device in which the deterioration of the light emitting layer in the functional layer is prevented and thereby the durability is improved. As a result, the display portion is particularly excellent in durability.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to embodiments thereof.
First, the wiring structure of the organic EL device as one embodiment of the present invention will be described with reference to FIG.
An organic EL device 1 shown in FIG. 1 is an active matrix organic EL device using a thin film transistor (hereinafter abbreviated as TFT) as a switching element.
[0023]
The organic EL device 1 includes a plurality of scanning lines 101, a plurality of signal lines 102 extending in a direction perpendicular to the scanning lines 101, and a plurality of power supply lines 103 extending in parallel to the signal lines 102. Are arranged, and pixel regions X are provided in the vicinity of the intersections of the scanning lines 101 and the signal lines 102.
A data line driving circuit 100 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102. Further, a scanning line driving circuit 80 including a shift register and a level shifter is connected to the scanning line 101.
[0024]
Further, in each pixel region X, a switching TFT 112 to which a scanning signal is supplied to the gate electrode via the scanning line 101, and a storage capacitor for holding a pixel signal supplied from the signal line 102 via the switching TFT 112. 113, a driving TFT 123 to which a pixel signal held by the holding capacitor 113 is supplied to a gate electrode, and a driving current from the power supply line 103 when electrically connected to the power supply line 103 via the driving TFT 123 And a functional layer 110 sandwiched between the pixel electrode 23 and the cathode (second electrode) 50 are provided. The pixel electrode 23, the cathode 50 and the functional layer 110 constitute a light emitting element (organic EL element).
[0025]
According to the organic EL device 1, when the scanning line 101 is driven and the switching TFT 112 is turned on, the potential of the signal line 102 at that time is held in the holding capacitor 113, and according to the state of the holding capacitor 113. The on / off state of the driving TFT 123 is determined. Then, current flows from the power supply line 103 to the pixel electrode 23 through the channel of the driving TFT 123, and further current flows to the cathode 50 through the functional layer 110. The functional layer 110 emits light according to the amount of current flowing through it.
[0026]
Next, a specific configuration of the organic EL device 1 of the present embodiment will be described with reference to FIGS. 3 is a cross-sectional view taken along the line AB in FIG. 2, FIG. 4 is a cross-sectional view taken along the line CD in FIG. 2, and FIG. 5 is an enlarged detailed view of the region 4 in FIG.
As shown in FIG. 2, the organic EL device 1 according to the present embodiment includes a substrate 20 having electrical insulation and pixel electrodes connected to a switching TFT (not shown) arranged in a matrix on the substrate 20. A pixel electrode area (not shown), a power supply line (not shown) arranged around the pixel electrode area and connected to each pixel electrode, and at least a rectangular shape in plan view located on the pixel electrode area The pixel portion 3 (within the dashed-dotted line frame in FIG. 2) is an active matrix type. However, a passive matrix type in which the cathode 50 is patterned in a stripe shape can be applied to the present embodiment. In the present invention, the substrate 20 and the switching TFT and various circuits formed on the substrate 20 as will be described later, and an interlayer insulating film are referred to as a base. (Indicated by reference numeral 200 in FIGS. 3 and 4)
[0027]
The pixel unit 3 includes a real display area 4 in the center (inside the two-dot chain line in FIG. 2) and a dummy area 5 (area between the one-dot chain line and the two-dot chain line) arranged around the real display area 4. It is divided into.
In the actual display area 4, display areas R, G, and B each having a pixel electrode are arranged in a matrix so as to be separated from each other in the AB direction and the CD direction.
Further, scanning line driving circuits 80 and 80 are arranged on both sides of the actual display area 4 in FIG. These scanning line drive circuits 80, 80 are arranged on the lower layer side of the dummy region 5.
[0028]
Further, an inspection circuit 90 is disposed above the actual display area 4 in FIG. This inspection circuit 90 is a circuit for inspecting the operating state of the organic EL device 1 and includes, for example, inspection information output means (not shown) for outputting the inspection result to the outside, and is displayed during manufacture or at the time of shipment. Equipment quality and defects can be inspected. The inspection circuit 90 is also disposed below the dummy area 5.
[0029]
The scanning line driving circuit 80 and the inspection circuit 90 are applied with a driving voltage from a predetermined power supply unit via the driving voltage conducting unit 310 (see FIG. 3) and the driving voltage conducting unit 340 (see FIG. 4). It is configured. The drive control signals and drive voltages to the scanning line drive circuit 80 and the inspection circuit 90 are supplied from a predetermined main driver that controls the operation of the organic EL device 1 and the drive control signal conduction unit 320 (see FIG. 3) and Transmission and application are performed via the drive voltage conduction unit 350 (see FIG. 4). The drive control signal in this case is a command signal from a main driver or the like related to control when the scanning line drive circuit 80 and the inspection circuit 90 output signals.
[0030]
Further, as shown in FIGS. 3 and 4, the organic EL device 1 includes a functional layer having a first electrode (pixel electrode 23) and a light emitting layer 60 and a second electrode (cathode 50) on a substrate 200. In particular, an adhesion layer 65 is provided between the light emitting layer 60 of the functional layer and the cathode 50. In the organic EL device 1, a gas barrier layer 30 is formed so as to cover the light emitting element.
[0031]
In the case of a so-called top emission type organic EL device, the substrate 20 constituting the base body 200 is configured to extract emitted light from the gas barrier layer 30 side that is the opposite side of the substrate 20, so that either a transparent substrate or an opaque substrate is used. Can also be used. Examples of opaque substrates include ceramics such as alumina, metal sheets such as stainless steel that have been subjected to insulation treatment such as surface oxidation, thermosetting resins and thermoplastic resins, and films thereof (plastic films). It is done.
[0032]
In the case of a so-called bottom emission type organic EL device, since the emitted light is extracted from the substrate 20 side, a transparent or semi-transparent substrate 20 is employed. For example, glass, quartz, resin (plastic, plastic film) and the like can be mentioned, and a glass substrate is particularly preferably used. In the present embodiment, a top emission type in which emitted light is extracted from the gas barrier layer 30 side, and thus the substrate 20 is made of an opaque material such as an opaque plastic film.
[0033]
A circuit unit 11 including a driving TFT 123 for driving the pixel electrode 23 and the like is formed on the substrate 20, and a large number of light emitting elements (organic EL elements) are provided thereon. As shown in FIG. 5, the light emitting element includes a pixel electrode (first electrode) 23 that functions as an anode, a hole transport layer 70 that injects / transports holes from the pixel electrode 23, and an electro-optic material. A light emitting layer 60 including one organic EL material, the adhesion layer 65, and a cathode (second electrode) 50 are formed in this order. Further, the cathode 50 is provided with an electron injection layer 67 made of an inorganic material having an electron injection effect on the inner surface side thereof, that is, on the adhesion layer 65 side.
Under such a configuration, the light emitting element has a structure in which holes injected from the hole transport layer 70 and electrons injected from the cathode 50 through the electron injection layer 67 are combined in the light emitting layer 60. Causes light emission.
[0034]
In this embodiment, the functional layer is composed of a hole transport layer 70 made of an organic material and a light emitting layer 60 also made of an organic material, as will be described later. However, the functional layer of the present invention is not limited to this. For example, a carrier injection layer or a carrier transport layer such as a hole injection layer, an electron injection layer, or an electron transport layer may be further provided. A layer (hole blocking layer) or an electron blocking layer (electron blocking layer) may be provided.
[0035]
Since the pixel electrode 23 is a top emission type in the present embodiment, it does not need to be transparent, and is therefore formed of an appropriate conductive material. For example, an ITO electrode can be used, and a structure in which aluminum or titanium is laminated as a reflective layer on the back surface (the surface opposite to the light emitting layer 60) can be used. In the case of the bottom emission type, of course, it is necessary to be transparent. In that case, a transparent conductive material such as ITO is preferably used.
[0036]
As a material for forming the hole transport layer 70, for example, a polythiophene derivative, a polypyrrole derivative, or a doped body thereof is used. Specifically, 3,4-polyethylenediosithiophene / polystyrene sulfonic acid (PEDOT / PSS) dispersion or the like is used.
[0037]
As a material for forming the light emitting layer 60, a known light emitting material capable of emitting fluorescence or phosphorescence can be used. Specifically, (poly) fluorene derivative (PF), (poly) paraphenylene vinylene derivative (PPV), polyphenylene derivative (PP), polyparaphenylene derivative (PPP), polyvinyl carbazole (PVK), polythiophene derivative, polymethyl Polysilanes such as phenylsilane (PMPS) are preferably used.
In addition, these polymer materials include polymer materials such as perylene dyes, coumarin dyes, rhodamine dyes, rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, and quinacridone. It can also be used by doping a low molecular weight material such as.
In addition, it replaces with the said polymeric material, and a conventionally well-known low molecular material can also be used.
[0038]
Further, in the present embodiment, the hole transport layer 70 and the light emitting layer 60 include the lyophilic control layer 25 formed in a lattice shape on the substrate 200 as shown in FIGS. The hole transport layer 70 and the light-emitting layer 60 surrounded by the organic bank layer 221 to be an element layer constituting a single light-emitting element (organic EL element). In addition, in the lyophilic control layer 25 and the organic bank layer 221 formed in a lattice shape, the outermost portion of the light emitting layer 60 in the state of covering the outermost portion, that is, the outermost portion of the light emitting layer 60 is covered. A surrounding portion is a surrounding member 201.
[0039]
Here, with respect to the surrounding member 201, in particular, in the organic bank layer 221 that forms the upper part, the angle θ of the surface 201 a that forms the outer portion with respect to the surface of the base body 200 is 110 degrees or more. The reason for this angle is that the step coverage of the adhesion layer 65, the electron injection layer 67, the cathode 50, and the gas barrier layer 30 formed thereon is improved, the adhesion layer 65 on the outer side, and the electron injection. This is to ensure the continuity of the layer 67, the cathode, and the gas barrier layer 30.
[0040]
The adhesion layer 65 is formed on these surfaces so as to cover the light emitting layer 60 and the organic bank layer 221, and is made of an organic silicon compound or an organic titanium compound. Specifically, methyltrimethoxysilane, tetraethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-mercaptopropyltrimethoxysilane, 3isocyanatopropyltrimethoxy as the organosilicon compound Alkoxysilane compounds having Si—O—R (R: alkyl) groups such as silane, silazane (Si—N) groups such as hexamethyldisilazane, hexamethylcyclotrisilazane, octamethylcyclotetrasilazane, tetramethyldisilazane, etc. A titanium alkoxide compound having a Ti—O—R group such as tetraisopropoxy titanium or methyltriethoxy titanium is preferably used as the organotitanium compound. In particular, among organosilicon compounds, aminosilanes and silazanes having nitrogen atoms such as amino groups having nitrogen atoms (such as —NH and —NH 2) and silazane groups are preferred.
The adhesion layer 65 made of such a material has a thickness of about 0.1 to 10 nm, and the thinner one is particularly preferable because electrons from the cathode 50 side can be easily passed. That is, the adhesion layer 65 only needs to be provided with at least a monomolecular layer on the surface of the light emitting layer 60 and the organic bank layer 221, and in this case, the adhesion layer 65 is not completely continuous, For example, there may be a microscopic missing part such as a mesh.
[0041]
Thus, even if not completely continuous, each molecule has an organic group and an inorganic group. Therefore, the adhesion group 65 has the organic group as the light emitting layer 60 and the organic bank layer 221. The inorganic group adheres well to the electron injection layer 67. Therefore, the adhesion layer 65 makes the electron injection layer 67 adhere well on the surfaces of the light emitting layer 60 and the organic bank layer 221. It is also conceivable that the adhesion layer 65 made of the material is partially decomposed by heat treatment at the time of film formation described later and has a molecular form different from the molecular form of the material. However, even in that case, the adhesion layer 65 is formed in a state where an inorganic group having silicon (Si) atoms and titanium (Ti) atoms and an organic group having carbon (C) atoms are mixed. The adhesion layer 65 has a function of favorably adhering the light emitting layer 60 and the organic bank layer 221 made of an organic material layer and the electron injection layer 67 made of an inorganic material.
Further, as shown in FIGS. 3 to 5, the adhesion layer 65 has an area larger than the total area of the actual display region 4 and the dummy region 5 in the present embodiment, and is formed so as to cover each. The light emitting layer 60, the organic bank layer 221, the upper surface of the enclosing member 201, and the surface 201 a that forms the outer side of the enclosing member 201 are all covered on the substrate 200.
[0042]
The electron injection layer 67 is formed on the adhesion layer 65 and is formed so as to cover at least the light emitting layer 60 on the lower side. As described above, the electron injection layer 67 is made of an inorganic material. Specifically, the electron injection layer 67 is made of a low work function metal such as lithium, calcium, sodium, magnesium, barium, or other group 1 and group 2 metal atoms. And metal fluorides and metal oxides such as lithium fluoride (LiF) and sodium oxide. The electron injection layer 67 made of such a material has a thickness of about 0.1 to 50 nm.
[0043]
In the present embodiment, the cathode 50 is formed so as to cover a wider range so that the adhesion layer 65 and the electron injection layer 67 are not exposed. However, the present invention is not limited to this, and it may be formed so as to cover a narrower range so that the end portions of the adhesion layer 65 and the electron injection layer 67 are exposed. The cathode 50 is made of an inorganic material, and is made of a metal such as aluminum, silver, or copper, or an alloy thereof, a metal oxide such as zinc oxide, tin oxide, titanium oxide, or tungsten oxide, or a metal nitride such as titanium nitride or It is formed of a metal oxynitride or a composite oxide such as ITO (indium tin oxide) or indium cerium oxide. Further, these materials may be formed by forming a film in multiple layers instead of a single layer. The cathode 50 made of such a material has a thickness of about 5 to 300 nm.
[0044]
In addition, since the organic EL device 1 of the present embodiment is a top emission type, the cathode 50 needs to have light transmissivity, and therefore transparent conductive ITO or the like is preferably used as a material. . Moreover, when using other materials, such as Ca and Al, it forms with the thickness which becomes fully transparent.
In this embodiment, since the active matrix type organic EL device uses a thin film transistor as a switching element, the cathode 50 and the electron injection layer 67 are different from the pixel electrode 23 and simply cover the area region. It is a film.
[0045]
In addition, the cathode 50 is connected to a cathode wiring 202 formed on the outer peripheral portion of the base body 200 outside the surface 201a of the surrounding member 201 as shown in FIG. A flexible substrate 203 is connected to the cathode wiring 202, whereby the cathode 50 is connected to a driving IC (driving circuit) (not shown) on the flexible substrate 203 via the cathode wiring 202. Yes.
[0046]
On the cathode 50, the adhesion layer 65 and the cathode 50 covering a wide range so that the light emitting layer 60, the organic bank layer 221, and the surrounding member 201 are not exposed are not exposed on the substrate 200. Further, a gas barrier layer 30 is provided so as to cover a wider range. The gas barrier layer 30 is for preventing oxygen and moisture from entering inside thereof, thereby preventing the entry of oxygen and moisture into the cathode 50 and the light emitting layer 60. This is intended to suppress alteration of the light emitting layer 60 and the like.
[0047]
The gas barrier layer 30 is made of, for example, an inorganic compound, and is preferably formed of a silicon compound, that is, silicon nitride, silicon oxynitride, silicon oxide, or the like. However, other than silicon compounds, for example, alumina or tantalum oxide may be used. Thus, if the gas barrier layer 30 is formed of an inorganic compound, the cathode 50 is made of ITO, so that the adhesion between the gas barrier layer 30 and the cathode 50 is improved, and therefore the gas barrier layer 30 is defective. As a result, the barrier property against oxygen and moisture becomes better.
[0048]
The gas barrier layer 30 may have a structure in which, for example, different layers within the range of the silicon compound are stacked. Specifically, the gas barrier layer 30 is formed in the order of silicon nitride and silicon oxynitride from the cathode 50 side, or The gas barrier layer 30 is preferably formed by forming silicon oxynitride and silicon oxide in this order from the cathode 50 side. In addition to such a combination, when two or more silicon oxynitrides having different composition ratios are stacked, the oxygen concentration of the layer on the cathode 50 side is lower than the oxygen concentration of the outer layer. It is preferable to do this.
In this way, since the oxygen concentration on the cathode 50 side is lower than that on the opposite side, the oxygen in the gas barrier layer 30 passes through the cathode 50 and reaches the light emitting layer 60 on the inner side, causing the light emitting layer 60 to deteriorate. It is possible to prevent the light emitting layer 60 from extending its life.
[0049]
Further, the gas barrier layer 30 may be configured so that its composition is non-uniform and its oxygen concentration changes continuously or discontinuously, without having a laminated structure. It is preferable for the reason described above that the oxygen concentration on the cathode 50 side be lower than the oxygen concentration on the outside.
The thickness of the gas barrier layer 30 is preferably 30 nm or more and 500 nm or less. If it is less than 30 nm, through holes may be partially formed due to film defects or film thickness variations, and the gas barrier property may be impaired. If it exceeds 500 nm, cracking due to stress occurs. This is because it may occur.
[0050]
The gas barrier layer 30 may be a multilayer film in which a titanium compound layer is formed as a base layer and a layer made of the silicon compound is laminated thereon.
As the titanium compound, those having ultraviolet absorptivity and photocatalytic activity such as titanium oxide, titanium oxynitride, and strontium titanate are particularly preferably used. Such a layer made of a titanium compound functions as an ultraviolet absorbing layer, thereby improving the light resistance when the organic EL device 1 is used outdoors. Further, as described above, when the silicon compound layer is formed on the titanium compound layer, the surface of the titanium compound layer is activated by light such as ultraviolet rays generated by the formation, and exhibits its photocatalytic activity. Then, even if impurities such as organic substances adhere to the surface of the titanium compound layer, for example, the impurities are decomposed and removed by the action of the photocatalyst, so that the silicon compound is favorably stacked on the titanium compound layer. .
In this embodiment, since it is a top emission type, the gas barrier layer 30 needs to have a light-transmitting property. Therefore, by appropriately adjusting the material and film thickness, the light beam in the visible light region can be adjusted in this embodiment. The transmittance is set to 80% or more, for example.
[0051]
A protection unit 204 is provided outside the gas barrier layer 30 so as to cover the gas barrier layer 30. In the present embodiment, the protective portion 204 includes two protective layers having different hardnesses, that is, a buffer layer 205 provided on the gas barrier layer 30 side, and a surface protective layer 206 provided thereon. Both of these two protective layers constitute the protective layer in the present invention.
The buffer layer 205 is in close contact with the gas barrier layer 30 and has a buffer function against mechanical shock from the outside. For example, urethane-based, acrylic-based, epoxy-based, polyolefin-based, silicone-based, fluororesin-based, etc. These are formed of an adhesive made of a resin material that is soft and has a low glass transition point. The buffer layer 205 is formed with a lower hardness than the surface protective layer 206.
[0052]
Such a buffer layer 205 may be formed into a porous body having fine pores by using, for example, a foam material in order to reduce the hardness thereof. If formed into a porous body in this way, the cushioning property is enhanced and the buffering function is further enhanced, and the light extraction efficiency that passes through the buffer layer 205, that is, the light transmittance is also increased, so that the top emission type is achieved. This is advantageous.
In addition, it is preferable to add about 1% of the organosilicon compound to the adhesive for forming the buffer layer 205, and in this way, the adhesion between the buffer layer 205 to be formed and the gas barrier layer 30. And therefore the buffer function against mechanical shock is increased. Further, particularly when the gas barrier layer 30 is formed of a silicon compound, the defects of the gas barrier layer 30 can be repaired by the organosilicon compound, and thus the gas barrier property of the gas barrier layer 30 can be improved.
[0053]
The surface protective layer 206 is provided on the buffer layer 205 to constitute the surface side of the protective portion 204, and has pressure resistance, wear resistance, external light antireflection, gas barrier property, ultraviolet blocking property, lens, and the like. It is a layer having at least one of functions such as sex. Specifically, it is formed of glass, a polymer layer (plastic film), a DLC (diamond like carbon) layer, an inorganic oxide layer such as silicon oxide, etc., and has a higher hardness than the buffer layer 205 as described above. By being formed of a material or having a higher hardness, the hardness is higher than that of the buffer layer 205. The hardness here means indentation hardness, Rockwell hardness generally applied to plastic materials, rebound hardness, Shore hardness applied to plastic materials and rubber materials, and scratches. The hardness is defined by hardness according to various test methods such as Mohs hardness applied to minerals. In the present invention, it is particularly preferable that the hardness is defined by indentation hardness or rebound hardness.
In the organic EL device of this example, when the top emission type is used, both the surface protective layer 206 and the buffer layer 205 need to be translucent, but when the bottom emission type is used, There is no need.
[0054]
A circuit unit 11 is provided below the light emitting element as shown in FIG. The circuit unit 11 is formed on the substrate 20 and constitutes the base body 200. That is, a base protective layer 281 mainly composed of SiO2 is formed on the surface of the substrate 20 as a base, and a silicon layer 241 is formed thereon. On the surface of the silicon layer 241, a gate insulating layer 282 mainly composed of SiO2 and / or SiN is formed.
[0055]
In the silicon layer 241, a region overlapping with the gate electrode 242 with the gate insulating layer 282 interposed therebetween is a channel region 241a. The gate electrode 242 is a part of the scanning line 101 (not shown). On the other hand, a first interlayer insulating layer 283 mainly composed of SiO 2 is formed on the surface of the gate insulating layer 282 that covers the silicon layer 241 and on which the gate electrode 242 is formed.
[0056]
Further, in the silicon layer 241, a low concentration source region 241b and a high concentration source region 241S are provided on the source side of the channel region 241a, while a low concentration drain region 241c and a high concentration drain are provided on the drain side of the channel region 241a. The region 241D is provided to form a so-called LDD (Light Doped Drain) structure. Among these, the high-concentration source region 241S is connected to the source electrode 243 through a contact hole 243a that opens over the gate insulating layer 282 and the first interlayer insulating layer 283. The source electrode 243 is configured as a part of the above-described power supply line 103 (see FIG. 1, extending in the direction perpendicular to the paper surface at the position of the source electrode 243 in FIG. 5). On the other hand, the high-concentration drain region 241D is connected to the drain electrode 244 made of the same layer as the source electrode 243 through a contact hole 244a that opens through the gate insulating layer 282 and the first interlayer insulating layer 283.
[0057]
The upper layer of the first interlayer insulating layer 283 on which the source electrode 243 and the drain electrode 244 are formed is covered with a second interlayer insulating layer 284 mainly composed of, for example, an acrylic resin component. The second interlayer insulating layer 284 is made of a material other than an acrylic insulating film, for example, SiN, SiO. ₂ Etc. can also be used. A pixel electrode 23 made of ITO is formed on the surface of the second interlayer insulating layer 284 and is connected to the drain electrode 244 through a contact hole 23a provided in the second interlayer insulating layer 284. Yes. That is, the pixel electrode 23 is connected to the high concentration drain region 241D of the silicon layer 241 through the drain electrode 244.
[0058]
Note that TFTs (driving circuit TFTs) included in the scanning line driving circuit 80 and the inspection circuit 90, that is, N-channel type or P-channel type TFTs constituting an inverter included in the shift register among these driving circuits, for example. The structure is the same as that of the driving TFT 123 except that it is not connected to the pixel electrode 23.
[0059]
On the surface of the second interlayer insulating layer 284 on which the pixel electrode 23 is formed, the pixel electrode 23, the lyophilic control layer 25 and the organic bank layer 221 are provided. The lyophilic control layer 25 is made of, for example, SiO. ₂ The organic bank layer 221 is made of acrylic resin, polyimide, COC (cyclic olefin copolymer resin), or the like. On the pixel electrode 23, the hole transport layer 70, the light emitting layer 60, and the opening 25 a provided in the lyophilic control layer 25 and the opening 221 a surrounded by the organic bank 221 are provided. Are stacked in this order. In addition, “lyophilic” of the lyophilic control layer 25 in this embodiment means that the lyophilic property is higher than at least materials such as acrylic and polyimide constituting the organic bank layer 221. .
The layers up to the second interlayer insulating layer 284 on the substrate 20 described above constitute the circuit unit 11.
[0060]
Here, in the organic EL device 1 of the present embodiment, each light emitting layer 60 is formed so that the light emission wavelength bands correspond to the three primary colors of light in order to perform color display. For example, as the light emitting layer 60, a red light emitting layer 60R whose light emission wavelength band corresponds to red, a green light emitting layer 60G corresponding to green, and a blue organic EL layer 60B corresponding to blue, respectively, are displayed. , G, and B constitute one pixel that performs color display with these display regions R, G, and B. In addition, a BM (black matrix) (not shown) in which metallic chromium is formed by sputtering or the like is formed between the organic bank layer 221 and the lyophilic control layer 25 at the boundary of each color display region. Yes.
[0061]
Next, an example of a method for manufacturing the organic EL device 1 of the present embodiment will be described with reference to FIGS. In the present embodiment, the case where the organic EL device 1 is a top emission type will be described. Moreover, each sectional view shown in FIGS. 6 to 10 corresponds to the sectional view taken along the line AB in FIG.
First, as shown in FIG. 6A, a base protective layer 281 is formed on the surface of the substrate 20. Next, after an amorphous silicon layer 501 is formed on the base protective layer 281 using an ICVD method, a plasma CVD method, or the like, crystal grains are grown by a laser annealing method or a rapid heating method to form a polysilicon layer.
[0062]
Next, as shown in FIG. 6B, the polysilicon layer is patterned by a photolithography method to form island-like silicon layers 241, 251 and 261. Among these, the silicon layer 241 is formed in the display region and constitutes a driving TFT 123 connected to the pixel electrode 23, and the silicon layers 251 and 261 are P-channel type included in the scanning line driving circuit 80. And N-channel type TFTs (driving circuit TFTs).
[0063]
Next, a gate insulating layer 282 made of a silicon oxide film having a thickness of about 30 nm to 200 nm is formed on the entire surface of the silicon layers 241, 251 and 261, and the base protective layer 281 by plasma CVD, thermal oxidation, or the like. Here, when the gate insulating layer 282 is formed using a thermal oxidation method, the silicon layers 241, 251 and 261 are also crystallized, and these silicon layers can be made into polysilicon layers.
[0064]
In addition, when channel doping is performed on the silicon layers 241, 251 and 261, for example, about 1 × 10 10 at this timing. ¹² / Cm ² Boron ions are implanted at a dose of. As a result, the silicon layers 241, 251 and 261 have an impurity concentration (calculated by the impurities after activation annealing) of about 1 × 10. ¹⁷ / Cm ³ This is a low concentration P-type silicon layer.
[0065]
Next, an ion implantation selection mask 502 is formed in a part of the channel layer of the P-channel TFT and the N-channel TFT, and in this state, phosphorus ions are about 1 × 10 6. ¹⁵ / Cm ² Ion implantation is performed with a dose amount of. As a result, as shown in FIG. 6C, high-concentration source regions 241S and 261S and high-concentration drain regions 241D and 261D are formed in the silicon layers 241 and 261.
[0066]
Next, a gate electrode forming conductive layer made of a metal film such as doped silicon, a silicide film, or an aluminum film, a chromium film, or a tantalum film is formed on the entire surface of the gate insulating layer 282. The thickness of this conductive layer is about 500 nm. Thereafter, as shown in FIG. 6D, a gate electrode 252 for forming a P-channel type driving circuit TFT, a gate electrode 242 for forming a pixel TFT, and an N-channel type driving circuit TFT are formed by photolithography. A gate electrode 262 to be formed is formed. Further, the drive control signal conducting portion 320 (350) and the first layer 121 of the cathode power supply wiring are also formed at the same time. In this case, the drive control signal conducting portion 320 (350) is disposed in the dummy region 5.
[0067]
Subsequently, using the gate electrodes 242, 252, and 262 as a mask, about 4 × 10 6 of phosphorus ions are applied to the silicon layers 241, 251, and 261. ¹³ / Cm ² Ion implantation is performed with a dose amount of. As a result, low-concentration impurities are introduced in a self-aligned manner with respect to the gate electrodes 242, 252 and 262, and as shown in FIG. 6 (d), the low-concentration source regions 241b and 261b in the silicon layers 241 and 261, and Low concentration drain regions 241c and 261c are formed. In addition, low concentration impurity regions 251S and 251D are formed in the silicon layer 251.
[0068]
Next, as shown in FIG. 7E, an ion implantation selection mask 503 is formed to cover portions other than the P-channel type driver circuit TFT. Using this ion implantation selection mask 503, boron ions are implanted into the silicon layer 251 by about 1.5 × 10 5. ¹⁵ / Cm ² Ion implantation is performed with a dose amount of. As a result, the gate electrode 252 constituting the TFT for the P-channel driver circuit also functions as a mask, so that the silicon layer 251 is doped with a high concentration impurity in a self-aligning manner. Therefore, the low-concentration impurity regions 251S and 251D are counter-doped and become source and drain regions of a P-type channel type driver circuit TFT.
[0069]
Next, as shown in FIG. 7F, a first interlayer insulating layer 283 is formed over the entire surface of the substrate 20, and the first interlayer insulating layer 283 and the gate insulating layer 282 are patterned using a photolithography method. Thus, a contact hole C is formed at a position corresponding to the source electrode and the drain electrode of each TFT.
[0070]
Next, as shown in FIG. 7G, a conductive layer 504 made of a metal such as aluminum, chromium, or tantalum is formed so as to cover the first interlayer insulating layer 283. The thickness of the conductive layer 504 is approximately 200 nm to 800 nm. Thereafter, in the conductive layer 504, a region 240a where the source electrode and the drain electrode of each TFT are to be formed, a region 310a where the driving voltage conducting portion 310 (340) is to be formed, and a second layer of the cathode power supply wiring are formed. A patterning mask 505 is formed so as to cover the region 122a to be formed, and the conductive layer 504 is etched so that the source electrodes 243, 253, 263, and the drain electrodes 244, 254, 264 shown in FIG. Form.
[0071]
Next, as shown in FIG. 8I, a second interlayer insulating layer 284 that covers the first interlayer insulating layer 283 on which these are formed is formed of a polymer material such as an acrylic resin. The second interlayer insulating layer 284 is preferably formed to a thickness of about 1 to 2 μm. SiN, SiO ₂ It is also possible to form a second interlayer insulating film by using a SiN film thickness of 200 nm, SiO 2 ₂ The film thickness is desirably 800 nm.
[0072]
Next, as shown in FIG. 8J, a portion of the second interlayer insulating layer 284 corresponding to the drain electrode 244 of the driving TFT is removed by etching to form a contact hole 23a.
Thereafter, a conductive film to be the pixel electrode 23 is formed so as to cover the entire surface of the substrate 20. Then, by patterning this conductive film, as shown in FIG. 9 (k), the pixel electrode 23 that is electrically connected to the drain electrode 244 through the contact hole 23a of the second interlayer insulating layer 284 is formed, and at the same time, the dummy region The dummy electrode 26 is also formed. In FIGS. 3 and 4, the pixel electrode 23 and the dummy pattern 26 are collectively referred to as the pixel electrode 23.
[0073]
The dummy pattern 26 is configured not to be connected to the lower metal wiring via the second interlayer insulating layer 284. That is, the dummy pattern 26 is arranged in an island shape and has the same shape as the pixel electrode 23 formed in the actual display region. Of course, the structure may be different from the shape of the pixel electrode 23 formed in the display region. In this case, the dummy pattern 26 includes at least the one located above the drive voltage conducting portion 310 (340).
[0074]
Next, as shown in FIG. 9L, a lyophilic control layer 25 as an insulating layer is formed on the pixel electrode 23, the dummy pattern 26, and the second interlayer insulating film. In the pixel electrode 23, the lyophilic control layer 25 is formed so as to partially open, and holes can be transferred from the pixel electrode 23 in the opening 25a (see also FIG. 3). On the contrary, in the dummy pattern 26 in which the opening 25a is not provided, the insulating layer (lyophilic control layer) 25 serves as a hole movement shielding layer and does not cause hole movement. Subsequently, in the lyophilic control layer 25, a BM (not shown) is formed in a concave portion formed between two different pixel electrodes 23. Specifically, a film is formed on the concave portion of the lyophilic control layer 25 by sputtering using metallic chromium.
[0075]
Next, as shown in FIG. 9 (m), an organic bank layer 221 is formed so as to cover a predetermined position of the lyophilic control layer 25, specifically, the BM. As a specific method for forming the organic bank layer, for example, an organic layer is formed by applying a resist in which a resist such as an acrylic resin or a polyimide resin is dissolved in a solvent by various coating methods such as a spin coating method or a dip coating method. . The constituent material of the organic layer may be any material as long as it does not dissolve in the ink solvent described later and is easily patterned by etching or the like.
[0076]
Subsequently, the organic layer is patterned using a photolithography technique and an etching technique, and a bank opening 221a is formed in the organic layer, thereby forming an organic bank layer 221 having a wall surface in the opening 221a. Here, in the organic bank layer 221, the angle θ with respect to the surface of the base body 200 is 110 degrees or more with respect to the portion forming the outermost periphery, that is, the surface 201 a that forms the outer side of the surrounding member 201 in the present invention described above. It is preferable to form such that By forming at such an angle, the step coverage of the cathode 50 and further the gas barrier layer 30 formed thereon can be improved.
In this case, the organic bank layer 221 includes at least a layer positioned above the drive control signal conducting unit 320.
[0077]
Next, a region showing lyophilicity and a region showing liquid repellency are formed on the surface of the organic bank layer 221. In the present embodiment, each region is formed by plasma processing. Specifically, in the plasma treatment, the upper surface of the organic bank layer 221, the wall surface of the opening 221a, the electrode surface 23c of the pixel electrode 23, and the upper surface of the lyophilic control layer 25 are made lyophilic. A lyophilic step, a lyophobic step for making the upper surface of the organic bank layer 221 and the wall surface of the opening lyophobic, and a cooling step.
[0078]
That is, the base material (substrate 20 including a bank or the like) is heated to a predetermined temperature, for example, about 70 to 80 ° C., and then plasma treatment using oxygen as a reactive gas in an atmospheric atmosphere as a lyophilic process (O ₂ Plasma treatment) is performed. Next, as a lyophobic process, plasma treatment (CF ₄ Plasma treatment) is performed, and then the substrate heated for the plasma treatment is cooled to room temperature, whereby lyophilicity and liquid repellency are imparted to predetermined locations.
[0079]
This CF ₄ In the plasma processing, the electrode surface 23c of the pixel electrode 23 and the lyophilic control layer 25 are also somewhat affected, but ITO that is a material of the pixel electrode 23 and SiO that is a constituent material of the lyophilic control layer 25. ₂ TiO ₂ And the like have poor affinity for fluorine, so that the hydroxyl group imparted in the lyophilic step is not substituted with the fluorine group, and the lyophilic property is maintained.
[0080]
Next, the hole transport layer 70 is formed by a hole transport layer forming step. In this hole transport layer forming step, for example, a hole transport layer material is applied onto the electrode surface 23c by a droplet discharge method such as an ink jet method or a spin coating method, and then a drying process and a heat treatment are performed. A hole transport layer 70 is formed on 23. When the hole transport layer material is selectively applied by, for example, the ink jet method, first, the hole transport layer material is filled in the ink jet head (not shown), and the discharge nozzle of the ink jet head is placed in the lyophilic control layer 25. A liquid droplet whose droplet amount is controlled from a discharge nozzle is controlled while moving the inkjet head and the base material (substrate 20) relative to the electrode surface 23c located in the formed opening 25a. It discharges to the electrode surface 23c. Next, the discharged droplets are dried and the hole transport layer 70 is formed by evaporating the dispersion medium and the solvent contained in the hole transport layer material.
[0081]
Here, the droplets ejected from the ejection nozzle spread on the electrode surface 23c that has been subjected to the lyophilic treatment, and are filled in the opening 25a of the lyophilic control layer 25. On the other hand, droplets are repelled and do not adhere on the upper surface of the organic bank layer 221 that has been subjected to the liquid repellent treatment. Therefore, even if the droplet is deviated from the predetermined discharge position and discharged onto the upper surface of the organic bank layer 221, the upper surface is not wetted by the droplet, and the repelled droplet is opened in the lyophilic control layer 25. Roll into part 25a.
In addition, after this hole transport layer formation process, in order to prevent the oxidation of the hole transport layer 70 and the light emitting layer 60, it is preferable to carry out in inert gas atmospheres, such as nitrogen atmosphere and argon atmosphere.
[0082]
Next, the light emitting layer 60 is formed by the light emitting layer forming step. In this light emitting layer forming step, the light emitting layer forming material is ejected onto the hole transport layer 70 by, for example, the above-described ink jet method, and then subjected to a drying process and a heat treatment to thereby form openings formed in the organic bank layer 221. The light emitting layer 60 is formed in 221a. In this light emitting layer forming step, a nonpolar solvent that is insoluble in the hole transporting layer 70 is used as a solvent used for the light emitting layer forming material in order to prevent re-dissolution of the hole transporting layer 70.
In this light emitting layer forming step, for example, a blue (B) light emitting layer forming material is selectively applied to a blue display region by the above-described ink jet method, dried, and then similarly treated with green (G), red (R) is also selectively applied to the display area and dried.
[0083]
Next, as shown in FIG. 10 (n), the adhesion layer 65 is formed by the adhesion layer forming step. In this adhesion layer forming step, for example, a physical vapor deposition method such as a vapor deposition method or a chemical vapor deposition method (CVD method) is suitably employed. In particular, the treatment atmosphere is a dry inert gas atmosphere and It is preferably under atmospheric pressure or reduced pressure. That is, the adhesion layer 65 is formed by vapor-depositing or vapor-depositing the above-mentioned adhesion layer forming material such as aminosilane or silazane in a dry inert gas atmosphere and at atmospheric pressure or reduced pressure. Thus, by setting it as dry inert gas atmosphere, the fall of the reaction in connection with the adhesion | attachment of the light emitting layer 60 by oxygen and a water | moisture content during manufacture can be prevented. As a vapor deposition method, vapor deposition at room temperature, vapor deposition by a resistance heating method, vapor deposition by a lamp heating method, or the like is employed.
[0084]
Here, vapor deposition at room temperature is a method in which the vapor of the adhesion layer forming material is generated without heating and is brought into contact with the formation position of the adhesion layer. For example, when hexamethyldisilazane which is a kind of silazane is used as a forming material, the boiling point thereof is about 126 ° C., and therefore this hexamethyldisilazane has a relatively large vapor pressure of about 1.3 kPa even at room temperature. . Therefore, a predetermined thin film (adhesion layer 65) can be formed only by bringing this vapor into contact with the formation site. Further, for example, the adhesive layer 65 can be formed by bubbling an inert gas such as nitrogen to the hexamethyldisilazane and applying the inert gas containing the hexamethyldisilazane vapor to the formation site. Furthermore, the adhesion layer 65 can also be formed by spraying hexamethyldisilazane in a mist form by a spray method. As described above, vapor deposition may be performed by heating the forming material to, for example, 100 ° C. or less by resistance heating or lamp heating.
[0085]
As the chemical vapor deposition method, a thermal CVD method or a plasma CVD method is preferably employed. In particular, when the plasma CVD method is adopted, there is a high possibility that the forming material is decomposed by the action of the plasma. In this case, however, inorganic silicon atoms or titanium atoms and organic carbon atoms coexist as essential atoms. Thus, the adhesion layer 65 is formed. Therefore, the obtained adhesion layer 65 exhibits the function of improving the adhesion well without impairing the function as the adhesion layer 65 in the present invention.
The adhesion layer 65 covers not only the light emitting layer 60, the organic bank layer 221 and the upper surface of the enclosing member 201, but also the surface 201a that forms the outer portion of the enclosing member 201. It forms so that it may become.
[0086]
Next, the electron injection layer 67 is formed by the electron injection layer formation step. In this electron injection layer forming step, for example, a physical vapor deposition method such as an evaporation method is employed, and the electron injection layer 67 is formed by depositing, for example, LiF. Here, physical vapor deposition methods include, for example, vapor deposition methods such as resistance heating vapor deposition and electron beam heat vapor deposition, ion plating methods, and sputtering such as microwave sputtering such as high-frequency sputtering and ECR (electron cyclotron resonance). A method or the like is preferably employed. The electron injection layer 67 is formed on the adhesion layer 65 so as to cover at least the upper surface side of the light emitting layer 60. However, similar to the adhesion layer 65, the upper surface of the light emitting layer 60 and the organic bank layer 221, the upper surface of the surrounding member 201, and the outer portion forming surface 201a may be covered so as to be formed. In the present embodiment, it is formed in the same manner as the adhesion layer 65.
[0087]
Next, the cathode 50 is formed by a cathode layer forming step. In this cathode layer forming step, for example, a physical vapor deposition method such as a vapor deposition method or a chemical vapor deposition method (CVD method) is employed, and the cathode 50 is formed by depositing, for example, ITO. Here, as the physical vapor deposition method, for example, a vapor deposition method such as resistance heating vapor deposition or electron beam thermal vapor deposition, an ion plating method, and a sputtering method such as microwave sputtering such as high-frequency sputtering or ECR method are preferable. As the chemical vapor deposition method, high-density plasma CVD such as helicon wave plasma, ICP (inductively coupled plasma), ECR plasma, surface wave plasma, or the like is preferably used. The cathode 50 may be formed on the adhesion layer 65 so as to cover at least the upper surface side of the light emitting layer 60 as in the case of the electron injection layer 67. In the present embodiment, Again, it is formed in the same manner as the adhesion layer 65. In this way, by forming the electron injection layer 67 and the cathode 50 so as to cover the outer surface forming surface 201a of the surrounding member 201 in the same manner as the adhesion layer 65, the electron injection layer 67 and the cathode 50 can reliably form the light emitting layer 60. Therefore, the light emitting layer 60 can be more reliably prevented from being deteriorated due to oxygen or moisture.
[0088]
Thereafter, as shown in FIG. 10 (o), the gas barrier layer 30 is formed in a state of covering the cathode 50, that is, covering a wider area so that the cathode 50 is not exposed on the substrate 200. As a method for forming the gas barrier layer 30, for example, a physical vapor deposition method such as an evaporation method or a chemical vapor deposition method is appropriately employed depending on the forming material. As the physical vapor deposition method, for example, a vapor deposition method such as electron beam heating vapor deposition, an ion plating method, a sputtering method such as microwave sputtering such as high-frequency sputtering or ECR method, and the like are preferably employed. As the chemical vapor deposition method, a high-density plasma CVD method such as helicon wave plasma, ICP (inductively coupled plasma), ECR plasma, or surface wave plasma is preferably employed.
[0089]
Here, the gas barrier layer 30 may be formed as a single layer using the same material as described above, or may be formed by stacking a plurality of layers using different materials. Although it is formed of layers, the composition may be formed so as to change continuously or discontinuously in the film thickness direction.
When a plurality of layers are laminated with different materials, for example, the inner layer (the cathode 50 side layer) is silicon nitride or silicon oxynitride, and the outer layer is silicon oxynitride or silicon oxide. And so on.
[0090]
In the present invention, in particular, the layer made of an inorganic material formed on the light emitting layer 60, that is, the electron injection layer 67, the cathode 50, and the gas barrier layer 30 are continuously formed by the vapor phase growth method. Is preferred. In this way, for example, by forming each layer by the same vapor phase growth method, the processing atmosphere can be made common or the processing atmosphere can be easily adjusted, so that productivity can be improved. it can. In addition, the substrate 200 on which the light emitting layer 60 is formed can be continuously formed without being exposed to the atmosphere, whereby deterioration of the light emitting layer 60 due to oxygen or moisture can be prevented.
[0091]
When the gas barrier layer 30 is formed on the substrate 20 in this way, a surface protective layer 206 made of non-alkali glass (OA10, 0.5 mm thickness) is prepared separately. Then, for example, a two-component curable epoxy adhesive as a material for forming the buffer layer 205 is applied to the surface protective layer 206 in a pattern on an adhesive surface by a silk screen printing method or the like.
Thereafter, the buffer layer forming material side of the surface protective layer 206 is pressure-bonded to the gas barrier layer 30 side of the above-described one in which the gas barrier layer 30 is separately formed, and the material is cured by heating as necessary, The buffer layer 205 is used. As a result, the organic EL device 1 having the protection unit 204 shown in FIGS. 3 and 4 is obtained.
When a plurality of organic EL devices 1 are formed on a plurality of substrates, a substrate (surface protective layer 206) to be a plurality of protection portions 204 is prepared correspondingly, and these are pressure-bonded. Thereafter, scribing is performed to obtain individual organic EL devices 1.
[0092]
In the organic EL device 1 thus obtained, the adhesion layer 65 is provided between the light emitting layer 60 and the organic bank layer 221 (partition walls) made of an organic material and the electron injection layer 67 made of an inorganic material. Therefore, when the organic silicon compound or the organic titanium compound constituting the adhesion layer 30 includes an inorganic group and an organic group, the light emitting layer 60, the organic bank layer 221 and the electron injection layer are provided. Adhesion with 67 is sufficiently satisfactorily achieved through the adhesion layer 65. Therefore, by preventing the permeation (penetration) of oxygen and moisture between them, deterioration of the light emitting layer 60 is particularly prevented, thereby improving durability.
[0093]
Further, since the gas barrier layer 30 is provided on the cathode 50 so as to cover the adhesion layer 65, the gas barrier layer 30 prevents the penetration of oxygen and moisture, and the light emitting layer 60, the organic bank layer 221 and the electrons. Since the space between the injection layer 67 can be further satisfactorily sealed, deterioration of the light emitting layer due to permeation of oxygen and moisture can be prevented more reliably, and the life of the light emitting element can be extended.
[0094]
Further, for example, when a mechanical impact is applied to the protective portion 204 side, the surface protective layer 206, which is a protective layer having a particularly high hardness against the applied impact, exhibits a stress that is resistant to this, such as pressure resistance and wear resistance. In addition, the buffer layer 205, which is a low-level protective layer, exhibits a function of absorbing and mitigating mechanical shock, and thus the protective unit 204 sufficiently exhibits a protective function against mechanical shock. Therefore, in the organic EL device 1, it is possible to reliably prevent the element performance from being impaired.
In particular, since the surface protective layer 206 has functions such as pressure resistance, abrasion resistance, light reflection prevention, gas barrier properties, and ultraviolet blocking properties, the light emitting layer 60, the cathode 50, and the gas barrier layer also have this function. It can be protected by the surface protective layer 206, and thus the lifetime of the light emitting element can be extended.
[0095]
In the organic EL device 1, the electron injection layer 67 made of an inorganic material is provided on the inner surface side of the cathode 50, that is, the adhesion layer 65 side. However, the present invention is not limited to this, and the electron injection layer 67 is not limited to this. The cathode 50 may be provided directly on the surface of the adhesion layer 65 without being provided. Also in this case, the cathode 50 is made of an inorganic material, so that the cathode 50 adheres well to the adhesion layer 65, and therefore, the light emitting layer 60 and the organic bank layer 221 (partition walls) made of an organic material and the inorganic material. A close contact with the cathode 50 is ensured by the adhesive layer 65.
[0096]
Moreover, about an electron injection layer, you may provide what consists of an organic material instead of what consists of said inorganic material. In that case, as shown in FIG. 11, an electron injection layer 67 made of this organic material can be formed on the light emitting layer 60 as a component of the functional layer of the present invention. As a material for forming the electron injection layer 67, a metal complex such as an aluminum quinolinol complex, an acetylacetone complex or a crown ether complex, an organic metal compound such as sodium benzoate, or a conductive organic material such as polyacetylene or polyphenyl is used. Such a forming material has a thickness of, for example, about 1 to 50 nm by a physical vapor deposition method such as room temperature vapor deposition, resistance heating vapor deposition, or lamp heating vapor deposition, or a chemical vapor deposition method such as thermal CVD or plasma CVD. The electron injection layer 67 is formed. Since the electron injection layer 67 is formed by the vapor phase growth method as described above, the electron injection layer 67 covers not only the light emitting layer 60 but also the organic bank layer 221 as shown in FIG. Will be formed.
[0097]
When the electron injection layer 67 made of an organic material is formed on the light emitting layer 60 in this way, the adhesion layer 65 is formed on the surface of the electron injection layer 67, and further, the cathode is formed on the adhesion layer 65. 50 is formed. Even in such a configuration, the adhesion layer 65 is provided between the electron injection layer 67 made of an organic material and the cathode 50 made of an inorganic material, thereby providing a sufficiently good adhesion therebetween, whereby oxygen and moisture can be obtained. It is possible to prevent the light emitting layer 60 from being deteriorated due to the above and to extend the life of the light emitting element.
[0098]
Further, the organic EL device 1 has been described by taking the top emission type as an example. However, the present invention is not limited to this, and the organic EL device 1 may be a bottom emission type or a type that emits emitted light on both sides. Applicable. In particular, in the case of the bottom emission type, it is not necessary to use a transparent electrode for the cathode 50, but also in this case, it is preferable to form at least the surface side of the cathode 50 in contact with the gas barrier layer 30 with an inorganic oxide.
In this way, since the surface side of the cathode 50 in contact with the gas barrier layer 30 is made of an inorganic oxide, the adhesion with the gas barrier layer 30 made of an inorganic compound or a silicon compound is improved, and therefore the gas barrier layer 30 is defective. It becomes a dense layer with no oxygen and moisture barrier properties.
[0099]
Further, in the case of a bottom emission type or a type that emits emitted light on both sides, the switching TFT 112 and the driving TFT 123 formed on the base 200 are not directly under the light emitting element, but the lyophilic control layer 25 and It is preferable to increase the aperture ratio by forming the organic bank layer 221 directly below.
Further, in the organic EL device 1, the protective unit 204 is configured by two layers of the surface protective layer 206 and the buffer layer 205, but the present invention is not limited to this, and the protective unit 204 is configured by three or more layers. You may make it do.
[0100]
Next, the electronic apparatus of the present invention will be described. The electronic apparatus of the present invention has the organic EL device as a display unit, and specifically, the one shown in FIG.
FIG. 12 is a perspective view showing an example of a mobile phone. In FIG. 12, reference numeral 1000 denotes a mobile phone main body, and reference numeral 1001 denotes a display unit using the organic EL device.
Since this electronic apparatus includes the organic EL device in which the life of the light emitting element is extended as a display unit, the electronic apparatus itself is also excellent in display reliability.
Note that the electronic device of the present invention is not limited to the above-described mobile phone, and can be applied to, for example, a portable information processing device, a wristwatch type electronic device, and the like.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a wiring structure of an organic EL device of the present invention.
FIG. 2 is a plan view schematically showing the configuration of the organic EL device of the present invention.
FIG. 3 is a cross-sectional view taken along line AB in FIG.
4 is a cross-sectional view taken along line CD in FIG.
5 is an enlarged cross-sectional view of a main part of FIG. 3;
FIG. 6 is a cross-sectional view illustrating a method for manufacturing an organic EL device in the order of steps.
7 is a cross-sectional view for explaining a process following the process in FIG. 6; FIG.
FIG. 8 is a cross-sectional view for explaining a step following the step of FIG. 7;
FIG. 9 is a cross-sectional view for explaining a step following the step of FIG. 8;
FIG. 10 is a cross-sectional view for explaining a process following the process in FIG. 9;
FIG. 11 is an enlarged cross-sectional view of a main part of another organic EL device of the present invention.
FIG. 12 is a perspective view showing an electronic apparatus of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Organic EL apparatus (electro-optical apparatus), 23 ... Pixel electrode (1st electrode),
30 ... Gas barrier layer, 50 ... Cathode (second electrode), 60 ... Light emitting layer (functional layer),
65 ... Adhesion layer, 67 ... Electron injection layer, 200 ... Substrate, 201 ... Enclosing member,
204 ... Protective part, 205 ... Buffer layer (protective layer),
206 ... surface protective layer (protective layer), 221 ... organic bank layer (partition)

Claims (16)

In an organic EL device in which a first electrode, a functional layer made of an organic material and having at least a light emitting layer, and a second electrode are arranged in this order on a substrate,
The light emitting layer is provided in a pixel region surrounded by a partition made of an organic material,
An adhesion layer made of an organosilicon compound or an organotitanium compound is provided on the surface of the partition wall and / or the functional layer,
2. The organic EL device according to claim 1, wherein the second electrode made of an inorganic material is provided on the surface of the adhesion layer. 2. The organic EL device according to claim 1, wherein the adhesion layer covers a wider range than the partition and the functional layer so as not to be exposed. The gas barrier layer is provided on the second electrode so as to cover a wider area than the adhesion layer and the second electrode so that the adhesion layer and the second electrode are not exposed. Organic EL device. The organic EL device according to claim 3, wherein the gas barrier layer is an insulating layer made of any one of an inorganic oxide, an inorganic nitride, and an inorganic oxynitride. The organic EL device according to claim 3, wherein the gas barrier layer is a silicon compound. The organic EL device according to claim 3, wherein the gas barrier layer is a multilayer film formed by laminating a titanium compound and a silicon compound. The organic EL device according to claim 1, wherein a protective layer is provided on the gas barrier layer. The electro-optical device according to claim 7, wherein the protective layer has a buffer function against mechanical shock. The electro-optical device according to claim 7, wherein the protective layer has a surface protection function. The organic EL device according to claim 1, wherein the organosilicon compound is aminosilane or silazane having a nitrogen atom. The organic EL device according to claim 1, wherein the functional layer includes at least one organic carrier injection / transport layer having a carrier injection or carrier transport effect. The organic EL device according to claim 1, wherein the second electrode includes an inorganic electron injection layer having an electron injection effect on the adhesion layer side. In a method for manufacturing an organic EL device, a first electrode, a functional layer made of an organic material and having at least an organic light emitting layer, and a second electrode are formed on a substrate in this order.
Providing the light emitting layer in a pixel region surrounded by a partition made of an organic material;
Providing an adhesion layer made of an organosilicon compound or an organotitanium compound on the surface of the partition wall and / or the functional layer;
And a step of providing the second electrode made of an inorganic material on the surface of the adhesive layer. The method of manufacturing an organic EL device according to claim 13, further comprising a step of providing a gas barrier layer on the second electrode. 15. The method of manufacturing an organic EL device according to claim 14, wherein the adhesion layer, the second electrode, and the gas barrier layer are continuously formed by a vapor deposition method. An electronic apparatus comprising the organic EL device according to any one of claims 1 to 12 or the organic EL device obtained by the production method according to any one of claims 13 to 15.

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