JP2010060930A - Optical interference filter, display, and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical interference filter which can improve the color purity, the color reproducibility, and the light extracting efficiency in a configuration emitting light from the cathode side, and also to provide a display and an electronic device which can display high-definition images over a long time. <P>SOLUTION: The optical interference filters 102 has a number of semi-transmissive layers 13 separated from one another with spacing and having a function of passing light partly and reflecting the remainder. It is built to repeat light reflection between adjoining two semi-transmissive layers 13 to generate interference and to emit the light of a wavelength matching the distance L between the two semi-transmissive layers 13. The semi-transmissive layer 13 is mainly made of a metallic material obtained by adding a metal different from Ag in atomic radius to Ag. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical interference filter, a display device, and an electronic apparatus.

An organic electroluminescence element (so-called organic EL element) is a light emitting element having a structure in which at least one light emitting organic layer (light emitting layer) is interposed between an anode and a cathode. In such a light emitting device, by applying an electric field between the cathode and the anode, electrons are injected into the light emitting layer from the cathode side and holes are injected from the anode side, and electrons and holes are injected into the light emitting layer. Recombination generates excitons, and when the excitons return to the ground state, the energy is emitted as light (see, for example, Patent Document 1 and Non-Patent Document 1).
In the so-called top emission type light emitting element, as disclosed in Patent Document 1, generally, the cathode has a semi-transmission property, and light is emitted from the cathode side.

  In the light emitting device according to Patent Document 1, the cathode is made of a thin film of MgAg (Mg: Ag = 9: 1) so that the cathode has electron injecting property and semi-transmitting property. In such a light emitting element, the anode is reflective, and the light generated in the light emitting layer is resonated between the cathode and the anode. Thereby, the brightness | luminance (as a result, current efficiency) of the light radiate | emitted from a light emitting element can be improved.

However, in the light emitting element according to Patent Document 1, since the cathode is made of MgAg as described above, the reflectance of the cathode with respect to the light generated in the light emitting layer is low. Therefore, the luminance of light emitted from the light emitting element cannot be sufficiently increased.
Ag is generally known as a highly reflective metal. However, when a thin film that is semi-transparent is formed using Ag, fine irregularities due to nuclei in which Ag atoms are aggregated by surface diffusion or surface migration are formed. The thin film which has is formed. Such a thin film has a problem that it exhibits optical characteristics different from that of bulk Ag due to plasmon absorption, and a high reflectance cannot be obtained.

Japanese Patent Laid-Open No. 2003-77681 Hitoshi Kuma. Et. Al ,. SID DIGEST, P1504 (2007)

  An object of the present invention is to provide an optical interference filter that can improve the color purity and color reproducibility of light and further improve the light extraction efficiency, and display high-quality images over a long period of time. An object of the present invention is to provide a display device and an electronic device that can be used.

Such an object is achieved by the present invention described below.
The optical interference filter of the present invention includes a plurality of semi-transmissive layers having light transparency,
Each of the semi-transmissive layers has a different refractive index, and has a plurality of light transmissive layers having light transmittance,
A plurality of the semi-transmissive layers and the light-transmissive layers are alternately stacked,
It is configured to repeat light reflection between the interfaces of the semi-transmissive layer and the light transmissive layer, to cause interference, and to emit light having a wavelength according to the distance between the interfaces. ,
Each of the semi-transmissive layers is characterized in that a main material is a metal material obtained by adding an additive metal having an atomic radius different from that of Ag to Ag.

  Thereby, when forming a thin film-like semi-transmissive layer, generation of fine irregularities due to nuclei in which Ag atoms are aggregated by surface diffusion or surface migration is prevented, and a thin film-like semi-transparent layer having excellent surface properties (flatness) is prevented. A transmission layer can be formed. Therefore, the semi-transmissive layer can be made semi-transmissive and have excellent reflectivity. As a result, the color purity and color reproducibility emitted from the cathode side of the light emitting element can be improved, and the light extraction efficiency can be increased, thereby providing an excellent light emitting element.

In the optical interference filter of the present invention, the difference between the atomic radius of Ag and the atomic radius of the additive metal is preferably 10% or more of the atomic radius of Ag.
Thereby, when forming a thin film-like semi-transmissive layer, generation | occurrence | production of the fine unevenness | corrugation by the nucleus which Ag atoms aggregated by surface diffusion or surface migration can be prevented more reliably.

In the optical interference filter of the present invention, it is preferable that the additive metal is any one of Mg, Cu, Zn, and Al, or a combination of two or more of these.
Thereby, the reflectance and stability of a semi-transmissive layer can be made excellent. Further, such an Ag alloy layer can be easily formed by various vapor deposition methods.
In the optical interference filter of the present invention, the metal material preferably has an Ag content of 80 to 99.9 atomic% and an additive metal content of 0.1 to 20 atomic%.
Thereby, the reflectance of a semi-transmissive layer can be made excellent.

In the optical interference filter according to the aspect of the invention, it is preferable that the semi-transmissive layer is formed using a vapor phase film forming method.
Thereby, a thin film-like semi-transmissive layer having excellent surface properties (flatness) can be formed relatively easily.
In the optical interference filter according to the aspect of the invention, it is preferable that the semi-transmissive layer is formed by co-evaporating Ag and the additive metal.
This makes it possible to relatively easily form a thin-film semi-transmissive layer having excellent surface properties (flatness) while increasing the range of selection of the additive metal to be used.

In the optical interference filter of the present invention, the thickness of the semi-transmissive layer is preferably 1 to 50 nm.
Thereby, the semi-transmissive layer can be made semi-transmissive (function of transmitting a part of light from the light-emitting element (light-emitting layer) and reflecting the remaining part).
In the optical interference filter according to the aspect of the invention, it is preferable that a reflectance of the semi-transmissive layer with respect to the light is 20 to 80%.
Thereby, the brightness | luminance of the light radiate | emitted from an optical interference filter can be raised effectively.

In the optical interference filter of the present invention, the light transmissive layer is mainly composed of a metal material obtained by adding an additive metal having an atomic radius different from that of Ag so that the refractive index is different from that of the semi-transmissive layer. It is preferable to be configured.
Thereby, a thin film-like light transmission layer having excellent surface properties (flatness) can be formed. As a result, each interface between the semi-transmissive layer and the light transmissive layer also has excellent surface properties, and light loss can be reduced.

In the optical interference filter of the present invention, it is preferable that the light transmission layer is composed of SiO ₂ or SiON as a main material.
Thereby, the difference in refractive index between the semi-transmissive layer and the light transmissive layer can be increased, and the reflection characteristics at each interface between the semi-transmissive layer and the light transmissive layer can be improved.
In the optical interference filter of the present invention, it is preferable that the light transmission layer has a thickness of 50 to 300 nm.
By forming the light transmission layer with such a film thickness, interference with visible light can be effectively generated.

The display device of the present invention includes the optical interference filter of the present invention,
A light emitting device having a cathode, an anode, and at least one light emitting layer provided between the cathode and the anode;
The light from the light emitting element is configured to be emitted through the optical interference filter.
Thereby, it is possible to provide a display device capable of displaying a high-quality image over a long period of time.

In the display device according to the aspect of the invention, it is preferable that the light emitting element has a top emission structure that emits light emitted from the at least one light emitting layer from the cathode side.
By using such a top emission type light emitting element, it is possible to provide a display device having a relatively simple configuration, high luminance, excellent color purity, color reproducibility, and extraction efficiency.
In the display device according to the aspect of the invention, it is preferable that the at least one light emitting layer includes a plurality of light emitting layers having different emission spectra, and the light emitting layer as a whole emits white light. .
Accordingly, various colors can be separated from one light emitting element and used.

In the display device of the present invention, the at least one light emitting layer includes a red light emitting layer that emits red light, a green light emitting layer that emits green light, and a blue light emitting layer that emits blue light. Is preferred.
Thereby, it is possible to emit white light over the plurality of light emitting layers relatively easily and reliably.
An electronic apparatus according to the present invention includes the display device according to the present invention.
Accordingly, an electronic device that can display a high-quality image over a long period of time can be provided.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a light emitting device manufacturing method, a display device, and an electronic apparatus according to the present invention are described below with reference to the accompanying drawings.
FIG. 1 is a schematic sectional view showing an example (display device) of a display device of the present invention, and FIG. 2 is a diagram schematically showing a longitudinal section of a light emitting element provided in the light emitting device shown in FIG. . In the following description, for convenience of explanation, the upper side in FIG. 1 and FIG. 2 will be described as “upper” and the lower side as “lower”.

(Display device)
Display device shown in FIG. 1 100, a plurality of light-emitting elements _{1 R,} 1 G, _{1 B} and the light emitting device 101 provided with an optical interference semitransparent provided corresponding to each light-emitting element _{1 R,} 1 G, _{1 B} And the optical interference filter 102 including the sections 19 _R , 19 _G , and 19 _B.
In such a display device 100, the plurality of light emitting elements 1 _R , 1 _G , 1 _B and the plurality of optical interference semi-transmissive portions 19 _R , 19 _G , 19 _B correspond to the sub pixels 100 _R , 100 _G , 100 _B. The display panel has a top emission structure.
In the present embodiment, an example in which an active matrix method is employed as a display device driving method will be described. However, a passive matrix method may be employed.

The light emitting device 101 includes a substrate 21, a plurality of light emitting elements 1 _R , 1 _G , 1 _B, and a plurality of switching elements 24.
The substrate 21 supports the plurality of light emitting elements 1 _R , 1 _G , 1 _B and the plurality of switching elements 24. Each light emitting element 1 _R , 1 _G , 1 _B of the present embodiment has a configuration for extracting light from the side opposite to the substrate 21 (top emission type). Accordingly, the substrate 21 can be either a transparent substrate or an opaque substrate. In the case where the light-emitting elements 1 _R, 1 _G, 1 _B is a structure in which light is extracted from the substrate 21 side (bottom emission type), the substrate 21 is substantially transparent (colorless and transparent, colored transparent or semi-transparent ).

  Examples of the constituent material of the substrate 21 include resin materials such as polyethylene terephthalate, polyethylene naphthalate, polypropylene, cycloolefin polymer, polyamide, polyethersulfone, polymethyl methacrylate, polycarbonate, and polyarylate, quartz glass, and soda glass. Such glass materials can be used, and one or more of these can be used in combination.

Examples of the opaque substrate include a substrate made of a ceramic material such as alumina, an oxide film (insulating film) formed on the surface of a metal substrate such as stainless steel, and a substrate made of a resin material. It is done.
Although the average thickness of such a board | substrate 21 is not specifically limited, It is preferable that it is about 0.1-30 mm, and it is more preferable that it is about 0.1-10 mm.

On such a substrate 21, a plurality of switching elements 24 are arranged in a matrix.
Each switching element 24 is provided corresponding to the respective light emitting elements _{1 R, 1 G, 1 B} , a driving transistor for driving the light emitting elements _{1 R, 1 G, 1 B} .
Each switching element 24 includes a semiconductor layer 241 made of silicon, a gate insulating layer 242 formed on the semiconductor layer 241, a gate electrode 243 formed on the gate insulating layer 242, a source electrode 244, And a drain electrode 245.

A planarizing layer 22 made of an insulating material is formed so as to cover the plurality of switching elements 24.
On the planarization layer 22, light emitting elements 1 _R , 1 _G , 1 _B are provided corresponding to the switching elements 24.
The light emitting element 1 _R is configured by laminating a reflective film 32, a corrosion preventing film 33, an anode 3, a laminate (organic EL light emitting unit) 15, a cathode 12, and a cathode cover 34 in this order on a planarizing layer 22. Yes. In the present embodiment, the anode 3 of each light emitting element 1 _R , 1 _G , 1 _B constitutes a pixel electrode and is electrically connected to the drain electrode 245 of each switching element 24 by a conductive portion (wiring) 27. . The cathode 12 of the light-emitting elements _{1 R, 1 G, 1 B} is a common electrode.
The light emitting elements 1 _R , 1 _G , and 1 _B will be described in detail later.

A partition wall 31 is provided between the adjacent light emitting elements 1 _R , 1 _G , 1 _B.
The optical interference filter 102 is bonded to the light emitting device 101 configured in this way through a resin layer 35 formed of a thermosetting resin having adhesiveness and transparency such as an epoxy resin.
The optical interference filter 102 includes a substrate 20, a plurality of optical interference semi-transmissive portions 19 _R , 19 _G , and 19 _B, and a light shielding layer 36.

The substrate (sealing substrate) 20 supports the optical interference semi-transmissive portions 19 _R , 19 _G , 19 _B and the light shielding layer 36. A transparent substrate is used as the substrate 20.
Such a constituent material of the substrate 20 is not particularly limited as long as the substrate 20 is light transmissive, and the same constituent materials as those of the substrate 21 described above can be used.
The optical interference semi-transmissive portions 19 _R , 19 _G , and 19 _B are provided corresponding to the light emitting elements 1 _R , 1 _G , and 1 _B.

Optical interference semi-transparent portion 19 _R is for converting light W _R from the light emitting element 1 _R red. The optical interference semi-transparent portion 19 _G is used to convert the W _G from the light-emitting element 1 _G to green. The optical interference semi-transparent portion 19 _B serves to convert the light W _B from the light-emitting element 1 _B to blue. By using such optical interference semi-transmissive portions 19 _R , 19 _G and 19 _{B in combination} with the light emitting elements 1 _R , 1 _G and 1 _B , a full color image can be displayed. The optical interference semi-transmissive portions 19 _R , 19 _G , and 19 _B will be described in detail later.
A light shielding layer 36 is formed between the adjacent optical interference semi-transmissive portions 19 _R , 19 _G , and 19 _B.
The light shielding layer 36 has a function of preventing unintended subpixels 100 _R , 100 _G , and 100 _B from emitting light.

(Light emitting element)
Here, based on FIG. 2, the light emitting elements 1 _R , 1 _G , and 1 _B will be described in detail.
The light-emitting elements (electroluminescent elements) 1 _R 1, 1 _G , and 1 _B shown in FIG. 2 are respectively R (red), G having different emission spectra between two electrodes (between the anode 3 and the cathode 12). A laminate 15 including three light emitting layers of (green) and B (blue) is interposed. As shown in FIG. 2, the laminate 15 includes a hole injection layer 4, a hole transport layer 5, a first light emitting layer (red light emitting layer) 6, and an intermediate layer 7 from the anode 3 side to the cathode 12 side. A second light emitting layer (blue light emitting layer) 8, a third light emitting layer (green light emitting layer) 9, an electron transport layer 10, and an electron injection layer 11 are laminated in this order.

In other words, each light emitting element 1 _R , 1 _G , 1 _B includes the anode 3, the hole injection layer 4, the hole transport layer 5, the first light emitting layer 6, the intermediate layer 7, and the second light emitting layer 8. The third light emitting layer 9, the electron transport layer 10, the electron injection layer 11, and the cathode 12 are laminated in this order.
In this embodiment, a reflective film 32 and a corrosion prevention film 33 are provided between the anode 3 and the planarizing layer 22, and a cathode cover (sealing) is provided on the opposite side of the cathode 12 from the laminate 15. Layer) 34 is provided.

In each of the light emitting elements 1 _R , 1 _G , and 1 _B , the cathode 12 side with respect to the light emitting layers of the first light emitting layer 6, the second light emitting layer 8, and the third light emitting layer 9. Electrons are supplied (injected) from, and holes are supplied (injected) from the anode 3 side. In each light emitting layer, holes and electrons recombine, and excitons (excitons) are generated by the energy released during the recombination, and energy (fluorescence or phosphorescence) is generated when the excitons return to the ground state. Is emitted (emitted).

In each of such light emitting elements 1 _R , 1 _G , 1 _B , the first light emitting layer 6, the second light emitting layer 8, and the third light emitting layer 9 are composed of a plurality of light emitting layers having different emission spectra. In addition, the entire light emitting layer of the plurality of layers is configured to emit white light. Therefore, while the light emitting elements 1 _R , 1 _G , and 1 _B have light emitting layers having the same configuration, desired colors can be separated and used by the light emitting elements 1 _R , 1 _G , and 1 _B , respectively. That is, various colors can be separated from one light emitting element.
In particular, since R, G, and B are combined to emit white light in the entire light emitting layer, white light can be emitted in the entire light emitting layer in a relatively simple and reliable manner.

Hereinafter, it will be described in order components constituting the light-emitting element 1 _R. Hereinafter, the light emitting element 1 _R will be described as a representative. The light-emitting elements 1 _G and 1 _B will be described with a focus on matters different from the light-emitting element 1 _R, and the description of the same matters will be omitted.
(anode)
The anode 3 is an electrode that injects holes into the hole transport layer 5 through a hole injection layer 4 described later. As a constituent material of the anode 3, it is preferable to use a material having a large work function and excellent conductivity.

Examples of the constituent material of the anode 3 include oxides such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), In ₃ O ₃ , SnO ₂ , Sb-containing SnO ₂ , and Al-containing ZnO, Au, Pt, and Ag. Cu, alloys containing these, and the like can be used, and one or more of these can be used in combination.
The anode 3 is adjusted semipermeable layer 13 and the distance the light emitting element 1 wavelength of the light emitted from the _R such that those corresponding to the (red wavelength) thickness between the reflective film 32 described later It is preferable.

Incidentally, the anode 3 For the light emitting element 1 _G, so that the distance between the transflective layer 13 and the reflective film 32 is one corresponding to the wavelength of the light emitted from the light emitting element 1 _G (green wavelength) thickness is preferably but is adjusted, also the anode 3 for the light emitting element 1 _B, the wavelength distance of the light emitted from the light emitting element 1 _B between the transflective layer 13 and the reflective film 32 (wavelength of blue) It is preferable that the thickness is adjusted so as to comply. This can increase the brightness of the desired chromaticity of the light emitting element 1 _R, 1 _G, 1 each emitted light _B. In this case, the thicknesses of the anodes 3 of the light emitting elements 1 _R , 1 _G and 1 _B are different from each other according to the wavelength of the emitted light.
The average thickness of the anode 3 is not particularly limited, but is preferably about 10 to 200 nm, and more preferably about 20 to 150 nm.
In the present embodiment, the anode 3 has optical transparency. Thereby, the reflective film 32 can reflect the light from each light emitting layer.

(Hole injection layer)
The hole injection layer 4 has a function of improving the hole injection efficiency from the anode 3 (that is, hole injection property).
The constituent material (hole injection material) of the hole injection layer 4 is not particularly limited as long as the hole injection layer 4 exhibits the hole injection property as described above. For example, tetraamine compounds and Derivatives thereof, copper phthalocyanine, N, N′-bis- (4-diphenylamino-phenyl) -N, N′-diphenyl-biphenyl-4,4′-diamine represented by the following chemical formula 1, 4,4 ′, 4 ″ -tris (N, N-phenyl-3-methylphenylamino) triphenylamine (m-MTDATA) represented, N, N′-di (naphthylene-1) represented by the following chemical formula 3 -Yl) -N, N′-bidiphenyl-benzidine (NPD) and the like can be mentioned, and one or more of these can be used in combination.

  The average thickness of the hole injection layer 4 is not particularly limited, but is preferably about 5 to 150 nm, and more preferably about 10 to 100 nm.

(Hole transport layer)
The hole transport layer 5 has a function of transporting holes injected from the anode 3 through the hole injection layer 4 to the first light emitting layer 6.
As the constituent material of the hole transport layer 5, various p-type polymer materials and various p-type low-molecular materials can be used alone or in combination. For example, N, N′-di (1-naphthyl) ) -N, N′-diphenyl-1,1′-diphenyl-4,4′-diamine (NPD), N, N′-diphenyl-N, N′-bis (3-methylphenyl) -1,1 ′ -A tetraarylbenzidine derivative such as -diphenyl-4,4'-diamine (TPD), a tetraaryldiaminofluorene compound or a derivative thereof (amine-based compound), etc. may be mentioned, and one or more of these may be combined Can be used.
The average thickness of the hole transport layer 5 is not particularly limited, but is preferably about 10 to 150 nm, and more preferably about 10 to 100 nm.

(First light emitting layer)
The first light-emitting layer 6 includes a first light-emitting material that emits light in a first color and a first host material that uses the first light-emitting material as a guest material. Such a first light-emitting layer 6 can be formed, for example, by doping the first host material as a dopant with the first light-emitting material that is a guest material. Note that the first host material can be omitted.

The first light emitting material is a red light emitting material that emits red light.
Such a red light emitting material is not particularly limited, and a red fluorescent material can be suitably used by using various red fluorescent materials and red phosphorescent materials in combination of one or more kinds.
The red fluorescent material is not particularly limited as long as it emits red fluorescence. For example, perylene derivatives, europium complexes, benzopyran derivatives, rhodamine derivatives, benzothioxanthene derivatives, porphyrin derivatives, Nile red, 2- (1, 1-dimethylethyl) -6- (2- (2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H-benzo (ij) quinolidin-9-yl) ethenyl)- 4H-pyran-4H-ylidene) propanedinitrile (DCJTB), 4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl) -4H-pyran (DCM) and the like.

The red phosphorescent material is not particularly limited as long as it emits red phosphorescence, and examples thereof include metal complexes such as iridium, ruthenium, platinum, osmium, rhenium, and palladium. Among the ligands of these metal complexes, And those having at least one of phenylpyridine skeleton, bipyridyl skeleton, porphyrin skeleton and the like. More specifically, tris (1-phenylisoquinoline) iridium, bis [2- (2′-benzo [4,5-α] thienyl) pyridinate-N, C ³ ′] iridium (acetylacetonate) (btp2Ir ( acac)), 2,3,7,8,12,13,17,18-octaethyl-12H, 23H-porphyrin-platinum (II), bis [2- (2′-benzo [4,5-α] thienyl ) Pyridinate-N, C ³ '] iridium, bis (2-phenylpyridine) iridium (acetylacetonate).

Among the above-mentioned, the red light emitting material preferably contains a perylene derivative. A perylene derivative is a light-emitting material with particularly high luminous efficiency. The perylene derivative has a particularly excellent function of capturing electrons. For this reason, the electrons injected from the cathode 12 side can be reliably captured by the first light-emitting layer 6 and can be prevented from being injected into the hole transport layer 5. As a result, it is possible to prevent the constituent materials of the hole injection layer 4 and the hole transport layer 5 from being reduced and deteriorated by electrons.
In particular, as the perylene derivative used for the red light emitting material, for example, a tetraphenyldiindenoperylene derivative such as a compound represented by the following chemical formula 4 is preferably used.

The first host material having such a red light emitting material as a guest material recombines holes and electrons to generate excitons, and transfers the exciton energy to the red light emitting material (Förster transfer). Or a Dexter movement) to excite the red light emitting material.
Such a first host material is not particularly limited as long as it exhibits the above-described function with respect to the red light emitting material to be used. When the red light emitting material includes a red fluorescent material, for example, Styrylarylene derivatives, tetracene derivatives (naphthacene derivatives) such as compounds represented by the following chemical formula 5, perylene derivatives such as compounds represented by the chemical formula 6 below, distyrylbenzene derivatives, distyrylamine derivatives, tris (8-quinolinolato) aluminum complexes (Alq ₃ ) quinolinolato metal complexes, triphenylamine tetramers, triarylamine derivatives, oxadiazole derivatives, silole derivatives, dicarbazole derivatives, oligothiophene derivatives, benzopyran derivatives, triazole derivatives, benzoxazole derivatives , Benzothiazo Le derivatives, quinoline derivatives, 4,4'-bis (2,2'-diphenylvinyl) biphenyl (DPVBi) and the like, may be used alone among these individually or in combination of two or more.

Among these, the first light emitting material preferably includes a tetracene derivative or a perylene derivative as described above. Thereby, holes from the first light emitting layer 6 to the second light emitting layer 8 can be transferred more smoothly through the intermediate layer 7.
Further, when the red light emitting material includes a red phosphorescent material, examples of the first host material include 3-phenyl-4- (1′-naphthyl) -5-phenylcarbazole, 4,4′-N, N ′. -Carbazole derivatives, such as dicarbazole biphenyl (CBP), etc. are mentioned, Among these, it can also be used individually by 1 type or in combination of 2 or more types.

  When the red light emitting material (guest material) and the first host material as described above are used, the content (dope amount) of the red light emitting material in the first light emitting layer 6 is 0.1 to 10 wt%. Is preferable, and it is more preferable that it is 1-5 wt%. By setting the content of the red light emitting material in such a range, the light emission efficiency can be optimized, and the amount of light emitted from the second light emitting layer 8 and the third light emitting layer 9 described later is balanced. In addition, the first light emitting layer 6 can emit light.

Further, since the red light emitting material as described above has a relatively small band gap, it easily emits light. Therefore, by providing the red light emitting layer closest to the anode 3, the blue light emitting layer and the green light emitting layer, which have a relatively large band gap and are difficult to emit light, can be set to the cathode 12 side, and each light emitting layer can emit light in a balanced manner.
Moreover, the average thickness of the 1st light emitting layer 6 is although it does not specifically limit, It is preferable that it is 1-100 nm, It is more preferable that it is 3-50 nm, It is further more preferable that it is 5-30 nm.

(Middle layer)
The intermediate layer 7 is provided between and in contact with the first light-emitting layer 6 and the second light-emitting layer 8 described later. The intermediate layer 7 has a function of preventing exciton energy from moving between the first light emitting layer 6 and the second light emitting layer 8. With this function, the first light emitting layer 6 and the second light emitting layer 8 can each emit light efficiently.

The constituent material of the intermediate layer 7 is not particularly limited as long as the intermediate layer 7 can exhibit the function as described above, but an amine material or the like can be used. A mixed material of the system material and the acene material can be preferably used.
The amine-based material used for the intermediate layer 7 is not particularly limited as long as it has an amine skeleton and the intermediate layer 7 exhibits the function described above. Among the hole transport materials, materials having an amine skeleton can be used, but benzidine-based amine derivatives are preferably used.

  In particular, among the benzidine-based amine derivatives, the amine-based material used for the intermediate layer 7 is preferably one in which two or more naphthyl groups are introduced. Examples of such benzidine-based amine derivatives include N, N′-bis (1-naphthyl) -N, N′-diphenyl [1,1′-biphenyl] -4,4′-diamine (α-NPD). And N, N, N ′, N′-tetranaphthyl-benzidine (TNB) and the like.

(Second light emitting layer)
The second light-emitting layer 8 includes a second light-emitting material that emits light in the second color and a second host material that uses the second light-emitting material as a guest material. Similar to the first light emitting layer 6 described above, the second light emitting layer 8 can be formed, for example, by doping the second host material as a dopant with the second light emitting material as a guest material. it can. Note that the second host material can be omitted.

The second light emitting material is a blue light emitting material that emits blue light.
Such a blue light-emitting material is not particularly limited, and a blue fluorescent material can be suitably used by using various blue fluorescent materials and blue phosphorescent materials in combination of one or more.
The blue fluorescent material is not particularly limited as long as it emits blue fluorescence. For example, distyryldiamine derivatives, distyryl derivatives, fluoranthene derivatives, pyrene derivatives, perylene and perylene derivatives such as compounds represented by the following chemical formula 7 , Anthracene derivative, benzoxazole derivative, benzothiazole derivative, benzimidazole derivative, chrysene derivative, phenanthrene derivative, distyrylbenzene derivative, tetraphenylbutadiene, 4,4′-bis (9-ethyl-3-carbazovinylene) -1,1 '-Biphenyl (BCzVBi), poly [(9.9-dioctylfluorene-2,7-diyl) -co- (2,5-dimethoxybenzene-1,4-diyl)], poly [(9,9-dihexyl) Oxyfluorene-2,7-diyl) -o Toco- (2-methoxy-5- {2-ethoxyhexyloxy} phenylene-1,4-diyl)], poly [(9,9-dioctylfluorene-2,7-diyl) -co- (ethylnyl) Benzene)] and the like, and one of these may be used alone or in combination of two or more.

In particular, since the distyryldiamine derivative such as the compound represented by Chemical Formula 7 as described above is excellent in the function of capturing holes, the second light emitting layer 8 contains a distyryldiamine derivative. The second light emitting layer 8 can emit light efficiently.
The blue phosphorescent material is not particularly limited as long as it emits blue phosphorescence, and examples thereof include metal complexes such as iridium, ruthenium, platinum, osmium, rhenium, and palladium. More specifically, bis [4,6-difluorophenyl pyridinium sulfonate -N, ^{C 2} '] - picolinate - iridium, tris [2- (2,4-difluorophenyl) pyridinate -N, ^{C 2']} iridium , bis [2- (3,5-trifluoromethyl) pyridinate -N, ^{C 2} '] - picolinate - iridium, bis (4,6-difluorophenyl pyridinium sulfonate -N, ^{C 2')} iridium (acetylacetonate ).

As the second host material, the same material as the first host material of the first light emitting layer 6 described above can be used.
When the blue light emitting material (guest material) and the second host material as described above are used, the content (dope amount) of the blue light emitting material in the second light emitting layer 8 is 0.1 to 20 wt%. Is preferable, and it is more preferable that it is 5-20 wt%. By setting the content of the blue light emitting material in such a range, the light emission efficiency can be optimized, and the balance with the light emission amount of the first light emitting layer 6 described above and the third light emitting layer 9 described later. The second light emitting layer 8 can emit light while taking
The average thickness of the second light emitting layer 8 is not particularly limited, but is preferably 1 to 100 nm, more preferably 5 to 60 nm, and further preferably 10 to 40 nm.

(Third light emitting layer)
The third light-emitting layer 9 includes a third light-emitting material that emits light in the third color and a third host material that uses the third light-emitting material as a guest material. Similar to the first light emitting layer 6 described above, the third light emitting layer 9 can be formed, for example, by doping a third host material as a dopant with a third light emitting material as a guest material. it can. Note that the third host material can be omitted.

The third light emitting material is a green light emitting material that emits green light.
Such a green light emitting material is not particularly limited, and a green fluorescent material can be suitably used by using various green fluorescent materials and green phosphorescent materials in combination of one or more kinds.
The green fluorescent material is not particularly limited as long as it emits green fluorescence. For example, a coumarin derivative, a quinacridone derivative such as a compound represented by the following chemical formula 8, 9,10-bis [(9-ethyl-3- Carbazole) -vinylenyl] -anthracene, poly (9,9-dihexyl-2,7-vinylenefluorenylene), poly [(9,9-dioctylfluorene-2,7-diyl) -co- (1,4- Diphenylene-vinylene-2-methoxy-5- {2-ethylhexyloxy} benzene)], poly [(9,9-dioctyl-2,7-divinylenefluorenylene) -ortho-co- (2-methoxy-5 -(2-ethoxylhexyloxy) -1,4-phenylene)] and the like, and one of these may be used alone or in combination of two or more. That.

  The green phosphorescent material is not particularly limited as long as it emits green phosphorescence, and examples thereof include metal complexes such as iridium, ruthenium, platinum, osmium, rhenium, and palladium. Among these, at least one of the ligands of these metal complexes preferably has a phenylpyridine skeleton, a bipyridyl skeleton, a porphyrin skeleton, or the like. More specifically, fac-tris (2-phenylpyridine) iridium (Ir (ppy) 3), bis (2-phenylpyridinate-N, C2 ′) iridium (acetylacetonate), fac-tris [5 -Fluoro-2- (5-trifluoromethyl-2-pyridine) phenyl-C, N] iridium.

As the third host material, the same material as the first host material of the first light emitting layer 6 described above can be used.
When the green light emitting material (guest material) and the third host material as described above are used, the content (dope amount) of the green light emitting material in the third light emitting layer 9 is 0.1 to 20 wt%. Is preferable, and it is more preferable that it is 1-20 wt%. By setting the content of the green light emitting material within such a range, it is possible to optimize the light emission efficiency, and to balance the light emission amounts of the first light emitting layer 6 and the second light emitting layer 8 described above. In addition, the third light emitting layer 9 can emit light.
Moreover, the average thickness of the 3rd light emitting layer 9 is although it does not specifically limit, It is preferable that it is 1-100 nm, It is more preferable that it is 5-60 nm, It is further more preferable that it is 10-40 nm.

(Electron transport layer)
The electron transport layer 10 has a function of transporting electrons injected from the cathode 12 through the electron injection layer 11 to the third light emitting layer 9.
As a constituent material (electron transport material) of the electron transport layer 10, for example, a quinoline derivative such as an organometallic complex having an 8-quinolinol or its derivative such as tris (8-quinolinolato) aluminum (Alq ₃ ) as a ligand. Oxadiazole derivatives, perylene derivatives, pyridine derivatives, pyrimidine derivatives, quinoxaline derivatives, diphenylquinone derivatives, nitro-substituted fluorene derivatives, and the like, and one or more of these can be used in combination.
Although the average thickness of the electron carrying layer 10 is not specifically limited, It is preferable that it is about 0.5-100 nm, and it is more preferable that it is about 1-50 nm.
The electron transport layer 10 can be omitted.

(Electron injection layer)
The electron injection layer 11 has a function of improving the efficiency of electron injection from the cathode 12.
Examples of the constituent material (electron injection material) of the electron injection layer 11 include various inorganic insulating materials and various inorganic semiconductor materials.

Examples of such inorganic insulating materials include alkali metal chalcogenides (oxides, sulfides, selenides, tellurides), alkaline earth metal chalcogenides, alkali metal halides, and alkaline earth metal halides. Of these, one or two or more of these can be used in combination. By forming the electron injection layer using these as main materials, the electron injection property can be further improved. In particular, an alkali metal compound (alkali metal chalcogenide, alkali metal halide, etc.) has a very small work function, and the light-emitting element 1 _R can obtain high luminance by forming the electron injection layer 11 using the work function. It becomes.

Examples of the alkali metal chalcogenide include Li ₂ O, LiO, Na ₂ S, Na ₂ Se, and NaO.
Examples of the alkaline earth metal chalcogenide include CaO, BaO, SrO, BeO, BaS, MgO, and CaSe.
Examples of the alkali metal halide include CsF, LiF, NaF, KF, LiCl, KCl, and NaCl.

Examples of the alkaline earth metal halide include CaF ₂ , BaF ₂ , SrF ₂ , MgF ₂ , and BeF ₂ .
In addition, as the inorganic semiconductor material, for example, an oxide including at least one element of Li, Na, Ba, Ca, Sr, Yb, Al, Ga, In, Cd, Mg, Si, Ta, Sb, and Zn , Nitrides, oxynitrides, and the like, and one or more of these can be used in combination.
The average thickness of the electron injection layer 11 is not particularly limited, but is preferably about 0.1 to 1000 nm, more preferably about 0.2 to 100 nm, and about 0.2 to 50 nm. Further preferred.
The electron injection layer 11 can be omitted.

(cathode)
The cathode 12 is an electrode that injects electrons into the electron transport layer 10 via the electron injection layer 11 described above.
As a constituent material of the cathode 12, a material having a small work function is used. For example, Li, Mg, Ca, Sr, La, Ce, Er, Eu, Sc, Y, Yb, Ag, Cu, Al, Cs, Rb, or an alloy containing these may be used, and one or more of these may be used in combination (for example, a multi-layer laminate).

In particular, when an alloy is used as the constituent material of the cathode 12, it is preferable to use an alloy containing a stable metal element such as Ag, Al, or Cu, specifically, an alloy such as MgAg, AlLi, or CuLi. By using such an alloy as a constituent material of the cathode 12, the electron injection efficiency and stability of the cathode can be made excellent.
Although the average thickness of such a cathode 12 is not specifically limited, It is preferable that it is about 1-50 nm, and it is more preferable that it is about 5-20 nm.
Incidentally, the cathode 12 is adjusted distance L is the light emitting element 1 wavelength of the light emitted from the _R such that those corresponding to the (red wavelength) thickness between the semi-transmissive layer 13 to be described later and the reflective film 32 May be. That is, the thicknesses of the cathodes 12 of the light emitting elements 1 _R , 1 _G , and 1 _B may be different from each other according to the wavelength of the emitted light.

(Reflective film)
The reflective film (reflective layer) 32 is provided on the side opposite to the cathode 12 with respect to the first light emitting layer 6, the second light emitting layer 8, and the third light emitting layer 9 described above. That is, the first light emitting layer 6, the second light emitting layer 8, and the third light emitting layer 9 are provided between the reflective film 32 and the cathode 12. In other words, the reflective film 32 is provided away from the semi-transmissive layer 13 in the thickness direction. Thereby, the brightness of the light emitted from the cathode 12 side of the light emitting element 1 _R can be increased by the optical action between the semi-transmissive layer 13 and the reflective film 32.

Such a reflective film 32 has a function of reflecting light from at least one of the first light emitting layer 6, the second light emitting layer 8, and the third light emitting layer 9. This allows the reflected light from the optical and the cathode 12 from at least one layer of the light-emitting layer is reflected by the reflecting film 32, increasing the luminance of the light emitting element 1 _R. As a result, the light emission efficiency of the light emitting element _1R can be improved.

The reflective film 32 is preferably configured to resonate light from at least one light emitting layer with the semi-transmissive layer 13 described above. This makes it possible to increase the strength and color purity of light emitted from the light-emitting element 1 _R. In this case, the reflective film 32 can resonate light with the semi-transmissive layer 13 by setting the distance L to the semi-transmissive layer 13 to a desired value. More specifically, when the wavelength of the chromaticity whose luminance is desired to be increased is λ, the distance L is set to nλ / 2 while taking into account the phase shift amount when the light is reflected by the reflective film 32 and the semi-transmissive layer 13. (Where n is a natural number).

The constituent material of the reflective film 32 is not particularly limited as long as the reflective film 32 can exhibit the above-described function, and Al, Ni, Co, Ag, an alloy containing these, or the like Can be used.
The reflective film 32 may be made of the same Ag alloy as that of the semi-transmissive layer 13 described above.
The reflective film 32 can also be formed of a dielectric multilayer film (optical multilayer thin film) in which high refractive index layers and low refractive index layers are alternately stacked.

The material constituting the high refractive index layer, for _{example, Ti 2 O, Ta 2 O} 5, niobium _{oxide, Al 2 O 3, HfO 2} , ZrO 2, although ThO ₂ and the like, in particular, _Ti 2 O, Ta ₂ O ₅ , niobium oxide and the like are preferably used.
Examples of the material constituting the low refractive index layer include MgF ₂ and SiO ₂ , and SiO ₂ is particularly preferably used.

The number and thickness of the high refractive index layer and the low refractive index layer constituting the reflection film 32 are set according to the required optical characteristics. In general, when a reflective film is formed of a dielectric multilayer film, the number of layers required to obtain the optical characteristics is 12 or more.
In the present embodiment, since the light-emitting element 1 _R is a top emission type, light transmitting the reflective film 32 is not required.

The thickness of the reflective film 32 is not particularly limited as long as it exhibits the functions described above, but is preferably about 1 to 100 nm.
The reflective film 32 can be omitted. In this case, the same effect as that of the reflective film 32 can be exhibited by configuring the above-described anode 3 to have reflectivity. Thus, while also maintaining a simple layer structure of the light-emitting element 1 _R, the reflected light from the optical and the cathode 12 from a light-emitting layer is reflected by the anode 3, it is possible to increase the luminance of the light emitting element 1 _R.

(Corrosion prevention film)
The corrosion prevention film 33 has a function of preventing the reflection film 32 from being corroded.
The constituent material of the corrosion prevention film 33 is not particularly limited as long as the corrosion prevention film 33 exhibits the function described above and does not impair the function of the reflection film 32 described above. Inorganic materials can be used.
The corrosion prevention film 33 may be omitted.

(Cathode cover)
The cathode cover 34 is provided so as to cover the anode 3, the laminate 15, and the cathode 12, and has a function of hermetically sealing them and blocking oxygen and moisture. By providing the cathode cover 34, effects such as improvement of the reliability of the light emitting element 1 _R and prevention of deterioration / deterioration (improvement of durability) can be obtained.
Examples of the constituent material of the cathode cover 34 include Al, Au, Cr, Nb, Ta, Ti, alloys containing these, silicon oxide, various resin materials, and the like. In addition, when using the material which has electroconductivity as a constituent material of the cathode cover 34, in order to prevent a short circuit, between the cathode cover 34 and the anode 3, the laminated body 15, and the cathode 12 as needed. Thus, an insulating film is preferably provided.
In the present embodiment, the resin layer 35 (sealing layer) and the optical filter 102 shown in FIG. 1 are also provided so as to cover the anode 3, the laminate 15 and the cathode 12, and these are hermetically sealed, Has the function of blocking oxygen and moisture.

(Optical filter)
As described above, the optical interference filter 102 includes a plurality of optical interference semi-transmissive portions 19 _R , 19 _G , and 19 _B.
The optical interference semi-transparent portion 19 _R is for converting light W _R from the light emitting element 1 _R red. The optical interference semi-transparent portion 19 _G is used to convert the W _G from the light-emitting element 1 _G to green. The optical interference semi-transparent portion 19 _B serves to convert the light W _B from the light-emitting element 1 _B to blue. Thereby, each of the optical interference semi-transmissive portions 19 _R , 19 _G , and 19 _B can improve the color purity of a desired color of the emitted light.

These optical interference semi-transmissive portions 19 _R , 19 _G and 19 _B have the same configuration except that their thicknesses are different from each other. Hereinafter, the optical interference semi-transmissive portion _19R will be described as a representative, and the description of the optical interference semi-transmissive portions 19 _G and 19 _B will be omitted.
As shown in FIG. 2, the optical interference semi-transmissive portion 19 _R is configured by alternately laminating a plurality of semi-transmissive layers 13 and transmissive layers 14 having different refractive indexes.

In the present embodiment, the optical interference semi-transmissive portion 19 _R has three semi-transmissive layers 13, and the transmissive layer 14 is interposed between the semi-transmissive layers 13.
Such an optical interference transmission part 19 _R (optical interference filter 102) repeats light reflection between the interfaces between the semi-transmissive layer 13 and the light transmissive layer 14, thereby causing interference between the interfaces. Light having a wavelength corresponding to the distance L can be emitted to the outside.

Each semi-transparent layer 13 has a function of reflecting the remainder passes through the part of the light from the light emitting element 1 _R described above.
Each semi-transmissive layer 13 is mainly composed of a metal material obtained by adding an additive metal having an atomic radius different from that of Ag to Ag.
Such a metal material can prevent Ag atoms from aggregating due to surface diffusion and surface migration when the thin film is formed. Therefore, the thin film obtained has excellent surface properties (flatness) by preventing the occurrence of fine irregularities due to nuclei in which Ag atoms are aggregated. Therefore, each semi-transmissive layer 13 mainly composed of such a metal material can have excellent reflectivity while having semi-transmissibility. As a result, it is possible to assume that the light-emitting element 1 _R enhance the color purity and color reproducibility of the light emitted from, excellent light extraction efficiency of the light-emitting element 1 _R.

  The additive metal is not particularly limited as long as it is a metal having an atomic radius different from the atomic radius of Ag (metal bond radius) and can form an Ag alloy, and various metals can be used. It is preferable to use a metal in which the difference between the atomic radius and the atomic radius of the added metal is 10% or more of the atomic radius of Ag. Thereby, when forming each thin-shaped semi-transmissive layer 13, generation | occurrence | production of the fine unevenness | corrugation by the nucleus which Ag atom aggregated by surface diffusion or surface migration can be prevented more reliably.

Among the additive metals having such an atomic radius, it is preferable to use a material having a small work function as the additive metal. Specifically, the additive metal is preferably any one of Mg, Cu, Zn, and Al, or a combination of two or more of these, and Mg and Cu are particularly preferably used. be able to.
Thereby, the reflectance and stability of each semi-transmissive layer 13 can be made excellent. Each of the semi-transmissive layers 13 can be easily formed by various vapor deposition methods.

  Further, the metal material preferably has an Ag content of 80 to 99.9 atomic%, an additive metal content of 0.1 to 20 atomic%, and an Ag content of 90 to 99.9. It is more preferable that the content of the additive metal is 0.1 to 10 atomic%. Thereby, the reflectance of each semi-transmissive layer 13 can be made excellent. On the other hand, when the content of Ag exceeds the upper limit or the content of the added metal is less than the lower limit, depending on the thickness of each semi-transmissive layer 13 or the type of the added metal, each semi-transmissive layer 13 may have minute unevenness. On the other hand, when the Ag content is less than the lower limit value or the additive metal content exceeds the upper limit value, the reflection of each semi-transmissive layer 13 depends on the thickness of the semi-transmissive layer 13 or the kind of the additive metal. It shows a tendency for the rate to decrease.

Each semi-transmissive layer 13 is preferably formed by using a vapor phase film forming method. Thereby, the thin film-like semi-transmissive layer 13 having excellent surface properties (flatness) can be formed relatively easily.
In particular, each semi-transmissive layer 13 is preferably formed by co-evaporation of Ag and an additive metal. This makes it possible to relatively easily form each semitransparent layer 13 in the form of a thin film having excellent surface properties (flatness) while increasing the range of selection of the additive metal to be used.

Further, the reflectance of each semi-transmissive layer 13 with respect to light from the light emitting element 1 _R (target wavelength emitted from the sub-pixel 100 _R ) is preferably 20 to 80%, and preferably 30 to 70%. Is more preferable. This can increase the brightness of the light emitted from the light emitting element 1 _R effectively.
In addition, the thickness of each semi-transmissive layer 13 is not particularly limited as long as it can exhibit the functions as described above, but is preferably 1 to 50 nm, and more preferably 1 to 30 nm. . This makes it possible to each semi-transparent layer 13 as having a semi-permeable (function of reflecting the remainder transmits a portion of light from the light emitting element 1 _R). On the other hand, when the thickness is less than the lower limit value, it is difficult to form the homogeneous semi-transmissive layer 13 depending on the constituent material of each semi-transmissive layer 13 or the like. On the other hand, when the thickness exceeds the upper limit value, it is difficult to make the semi-transmissive layer 13 semi-transmissive depending on the constituent material of each semi-transmissive layer 13 and the like.

The light transmissive layer 14 has a refractive index different from that of each semi-transmissive layer 13, and is light transmissive with respect to light from the light emitting element 1 _R.
The light transmissive layer 14 has a function of defining a distance L between the pair of semi-transmissive layers 13 and 13.
The thickness of such a light transmission layer 14 is set so that light of a predetermined wavelength (red wavelength) interferes between two adjacent semi-transmission layers 13. This makes it possible to increase the strength and color purity of light emitted from the optical interference semi-transmission part 19 _R. In this case, by adjusting the thickness of the light transmissive layer 14 and setting the distance L between the two semi transmissive layers 13 adjacent to each other to a desired value, light is transmitted between the two semi transmissive layers 13 and 13. Can interfere. More specifically, when the wavelength of the chromaticity whose luminance is desired to be increased is λ, the thickness of the light transmission layer 14 (that is, the phase shift amount at the time of light reflection at each semi-transmission layer 13 and the like) The distance L) is about nλ / 2 (where n is a natural number).

Specifically, the thickness of each light transmission layer 14 is determined according to the wavelength of the light used as described above, and is not particularly limited, but is preferably 50 to 300 nm. By forming the light transmission layer 14 with such a film thickness, interference with visible light can be effectively generated.
The constituent material of the light transmission layer 14 is not particularly limited as long as it can transmit light having a desired wavelength, and various inorganic materials and various organic materials can be used.
The light transmissive layer 14 is mainly composed of a metal material obtained by adding an additive metal having a different atomic radius from Ag to Ag so that the refractive index is different from that of the semi-transmissive layer 13. preferable. Thereby, the thin-film-shaped light transmission layer 14 which has the outstanding surface property (flatness) can be formed. As a result, each interface between the semi-transmissive layer 13 and the light transmissive layer 14 also has excellent surface properties, and light loss can be reduced.
The light transmission layer 14 is preferably composed of SiO ₂ or SiON as a main material. Thereby, the difference in refractive index between the semi-transmissive layer 13 and the light transmissive layer 14 can be increased, and the reflection characteristics at each interface between the semi-transmissive layer 13 and the light transmissive layer 14 can be improved.

According to the optical interference semi-transmissive portion 19 _R configured as described above, since each semi-transmissive layer 13 is mainly composed of an Ag alloy, surface diffusion or Generation of fine irregularities due to nuclei in which Ag atoms are aggregated by surface migration can be prevented, and the thin film-like semi-transmissive layer 13 having excellent surface properties (flatness) can be formed. Therefore, each semi-transmissive layer 13 can be made semi-transmissive and have excellent reflectivity. As a result, it is possible to assume that enhance the color purity and color reproducibility of the light emitted from the optical interference semi-transmission part 19 _R, excellent light extraction efficiency of the light-emitting element.
Such an optical interference filter 102 (optical interference semi-transmission part 19 _R ) is combined with the top emission type light emitting element 1 _R , so that it has a relatively simple configuration with high luminance and excellent color purity, color reproducibility, and extraction. The display device 100 having efficiency can be provided.

(Method for manufacturing optical interference filter)
The optical interference filter 102 configured as described above can be manufactured, for example, as follows.
[1] First, the substrate 20 is prepared, and the light shielding portion 36 is formed on the substrate 20.
For example, the light shielding part 36 is formed by chemical vapor deposition (CVD) such as plasma CVD or thermal CVD, dry plating such as vacuum deposition, wet plating such as electrolytic plating, thermal spraying, sol-gel method, MOD method, metal, etc. It can be formed using foil bonding or the like.

[2] Next, the optical interference semi-transmissive portions 19 _R , 19 _G , and 19 _B are formed in the opening of the light shielding portion 36.
More specifically, the semi-transmissive layers 13 and the light transmissive layers 14 are alternately stacked.
The semi-transmissive layer 13 and the light transmissive layer 14 can be formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering, or the like.
At that time, each light transmission layer 14 is set so that the thickness thereof corresponds to the wavelength of each pixel as described above.

The optical interference filter 102 is obtained through the steps as described above.
The optical interference filter 102 thus obtained is bonded to the light emitting device 101 via a resin layer 35 made of a thermosetting resin having adhesiveness and transparency such as an epoxy resin. Thereby, the display apparatus 100 is obtained.
The display device 100 (the display device of the present invention) as described above can be incorporated into various electronic devices.

FIG. 3 is a perspective view showing the configuration of a mobile (or notebook) personal computer to which the electronic apparatus of the present invention is applied.
In this figure, a personal computer 1100 includes a main body 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display. The display unit 1106 is rotatable with respect to the main body 1104 via a hinge structure. It is supported by.
In the personal computer 1100, the display unit included in the display unit 1106 is configured by the display device 100 described above.

FIG. 4 is a perspective view showing a configuration of a mobile phone (including PHS) to which the electronic apparatus of the present invention is applied.
In this figure, a cellular phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204 and a mouthpiece 1206, and a display unit.
In the cellular phone 1200, the display unit is configured by the display device 100 described above.

FIG. 5 is a perspective view showing a configuration of a digital still camera to which the electronic apparatus of the present invention is applied. In this figure, connection with an external device is also simply shown.
Here, an ordinary camera sensitizes a silver salt photographic film with a light image of a subject, whereas a digital still camera 1300 photoelectrically converts a light image of a subject with an image sensor such as a CCD (Charge Coupled Device). An imaging signal (image signal) is generated.

A display unit is provided on the back of a case (body) 1302 in the digital still camera 1300, and is configured to display based on an imaging signal from the CCD, and functions as a finder that displays an object as an electronic image.
In the digital still camera 1300, the display unit is configured by the display device 100 described above.

A circuit board 1308 is installed inside the case. The circuit board 1308 is provided with a memory that can store (store) an imaging signal.
A light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided on the front side of the case 1302 (on the back side in the illustrated configuration).
When the photographer confirms the subject image displayed on the display unit and presses the shutter button 1306, the CCD image pickup signal at that time is transferred and stored in the memory of the circuit board 1308.

  In the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312 and a personal computer 1440 is connected to the data communication input / output terminal 1314 as necessary. Further, the imaging signal stored in the memory of the circuit board 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation.

  The electronic apparatus of the present invention includes, for example, a television, a video camera, a viewfinder type, in addition to the personal computer (mobile personal computer) in FIG. 3, the mobile phone in FIG. 4, and the digital still camera in FIG. Monitor direct-view video tape recorder, laptop personal computer, car navigation system, pager, electronic notebook (including communication function), electronic dictionary, calculator, electronic game device, word processor, workstation, video phone, security TV Monitors, electronic binoculars, POS terminals, devices equipped with touch panels (for example, cash dispensers and automatic ticket vending machines for financial institutions), medical devices (for example, electronic thermometers, blood pressure monitors, blood glucose meters, electrocardiographs, ultrasound diagnostic devices, internal Endoscope display device), fish finder, various measuring instruments, Vessels such (e.g., gages for vehicles, aircraft, and ships), a flight simulator, various monitors, and a projection display such as a projector.

The light emitting element, the display device, and the electronic device of the present invention have been described based on the illustrated embodiments, but the present invention is not limited to these.
For example, in the above-described embodiment, each light emitting element has been described as having three light emitting layers. However, the light emitting layer may be one layer, two layers, or four layers or more. Further, the emission color of the light emitting layer is not limited to R, G, and B in the above-described embodiment. Even when there are two or more light emitting layers, white light can be emitted by appropriately setting the emission spectrum of each light emitting layer. For example, when there are two light emitting layers, white light can be emitted by combining a blue light emitting layer and a yellow light emitting layer.

Next, specific examples of the present invention will be described.
1. Measurement of surface roughness of film A film composed of Ag (sample 1) and a film composed of Ag alloy (samples 2 to 5) were formed on a glass substrate by vacuum deposition. Here, as constituent materials of each film, Ag in sample 1, AgMg (Ag: Mg = 10: 1) in sample 2, AgCu (Ag: Cu = 10: 1) in sample 3, AgZn (Ag: Zn = 10: 1) and Sample 5 were made of AgNd (Ag: Nd = 10: 1), and the thicknesses of Samples 1 to 5 were 10 nm.
And about each sample 1-5, surface roughness (root mean square surface roughness [nm]) was measured using AFM (atomic force microscope). The results are shown in Table 1.

  As is clear from Table 1, the films of Samples 2 to 5 using an Ag alloy have excellent flatness compared to the film of Sample 1 using Ag (that is, reflection of light). It is understood that the property is excellent. In particular, the flatness of the film of Sample 2 using AgMg was excellent.

2. Production of light-emitting elements (Examples)
<1> First, a transparent glass substrate having an average thickness of 0.5 mm was prepared. Next, an Ag reflective film for pixels and an ITO electrode (anode) were formed on the substrate in this order by sputtering. Here, the average thickness of the ITO electrode for the R pixel was 110 nm, the average thickness of the ITO electrode for the G pixel was 70 nm, and the average thickness of the ITO electrode for the B pixel was 30 nm. The average thickness of the Ag reflection film was 100 nm.
And after immersing a board | substrate in order of acetone and 2-propanol and ultrasonically cleaning, the oxygen plasma process was performed.

<2> Next, a tetraamine compound represented by Chemical Formula 1 was deposited on the ITO electrode by a vacuum deposition method to form a hole injection layer having an average thickness of 40 nm.
<3> Next, on the hole injection layer, NPD represented by the above chemical formula 3 was vapor-deposited by a vacuum vapor deposition method to form a hole transport layer having an average thickness of 20 nm.
<4> Next, the constituent material of the red light-emitting layer was deposited on the hole transport layer by a vacuum vapor deposition method to form a red light-emitting layer (first light-emitting layer) having an average thickness of 10 nm. As a constituent material of the red light emitting layer, a compound represented by the above chemical formula 4 was used as a red light emitting material (guest material), and a compound represented by the above chemical formula 5 was used as a host material. The content (dope concentration) of the light emitting material (dopant) in the red light emitting layer was 1.0 wt%.

<5> Next, the constituent material of the intermediate layer was vapor-deposited on the red light emitting layer by a vacuum vapor deposition method to form an intermediate layer having an average thickness of 7 nm. As the constituent material of the intermediate layer, NPD represented by the above chemical formula 3 was used as an amine-based material.
<6> Next, the constituent material of the blue light-emitting layer was deposited on the intermediate layer by a vacuum vapor deposition method to form a blue light-emitting layer (second light-emitting layer) having an average thickness of 10 nm. As a constituent material of the blue light emitting layer, a compound represented by the above chemical formula 7 was used as a blue light emitting material, and a compound represented by the above chemical formula 6 was used as a host material. Further, the content (dope concentration) of the blue light emitting material (dopant) in the blue light emitting layer was 6.0 wt%.

<7> Next, the constituent material of the green light emitting layer was deposited on the blue light emitting layer by a vacuum deposition method, thereby forming a green light emitting layer (third light emitting layer) having an average thickness of 30 nm. As a constituent material of the green light emitting layer, a compound represented by the above chemical formula 8 was used as a green light emitting material (guest material), and a compound represented by the above chemical formula 6 was used as a host material. Further, the content (dope concentration) of the green light emitting material (dopant) in the green light emitting layer was 1.0 wt%.
<8> Next, on the green light-emitting layer, tris (8-quinolinolato) aluminum (Alq ₃ ) was formed by a vacuum deposition method to form an electron transport layer having an average thickness of 10 nm.

<9> Next, on the electron transport layer, LiF was formed into a film by a vacuum evaporation method to form a cathode having an average thickness of 1 nm.
<10> Next, an MgAg (Mg: Ag = 10: 1) film was formed on the electron injection layer by a vacuum deposition method to form a cathode having an average thickness of 5 nm. As a result, a light emitting device including a light emitting element of each pixel was obtained.
<11> On the other hand, AgMg (Ag: Mg = 10: 1) and SiON are alternately formed on a glass substrate by a vacuum evaporation method (co-evaporation method), and a three-layer semi-transmission as shown in FIG. A two-layer light-transmitting layer was formed, and an optical interference semi-transmitting portion of each pixel was obtained.

Here, with respect to the light transmission layer, light of 610 nm for the R pixel, 530 nm for the G pixel, and 460 nm for the B pixel may interfere (resonate) between the interfaces of the semi-transmission layer and the light transmission layer. The thickness was set. Specifically, the average thickness of each light transmission layer for the R pixel is 160 nm, the average thickness of each light transmission layer for the G pixel is 133 nm, and the average thickness of each light transmission layer for the B pixel is 107 nm.
The refractive index n of the semi-transmissive layer (AgMg) was 0.26 for light with a wavelength of 460 nm, 0.20 for light with a wavelength of 530 nm, and 0.21 for light with a wavelength of 610 nm. The refractive index n of the light transmission layer (SiON) was 01.78 for light with a wavelength of 460 nm, 1.76 for light with a wavelength of 530 nm, and 1.75 for light with a wavelength of 610 nm.

<12> Then, the side opposite to the glass substrate of the optical interference semi-transmissive portion and the cathode side of the light emitting device obtained in the above step <10> were joined with an epoxy resin. Here, the average thickness of the bonding layer made of epoxy resin was 100 μm.
As described above, a display device having R, G, and B sub-pixels was obtained.

(Comparative Example 1)
A light emitting device for each of R, G, and B pixels was manufactured in the same manner as in Example 1 except that the above-described steps <11> and <12> were omitted.
(Comparative Example 2)
A display device was manufactured in the same manner as in Example 1 except that a semi-transmissive layer was formed using Ag instead of AgMg, and the thickness of the light-transmitting layer was changed as shown in Table 1. .

Here, the light transmission layer is thick so that light of 610 nm for the R pixel, 530 nm for the G pixel, and 460 nm for the B pixel interfere (resonate) between the interfaces of the semi-transmission layer and the light transmission layer. Set. Specifically, the average thickness of the light transmission layer for the R pixel is 160 nm, the average thickness of the light transmission layer for the G pixel is 130 nm, and the average thickness of the light transmission layer for the B pixel is 100 nm. .
The refractive index n of the semi-transmissive layer (Ag) was 1.42 for light having a wavelength of 460 nm, 2.53 for light having a wavelength of 530 nm, and 3.03 for light having a wavelength of 610 nm.

(Comparative Example 3)
Example 1 described above except that a semi-transmissive layer is formed using MgAg (Mg: Ag = 10: 1) instead of AgMg, and the thickness of the light-transmitting layer is changed as shown in Table 1. A display device was manufactured in the same manner.
Here, the thickness of the light transmission layer was set so that light of 610 nm for the R pixel, 530 nm for the G pixel, and 460 nm for the B pixel resonated between the interfaces of the semi-transmission layer and the light transmission layer. . Specifically, the average thickness of the light transmission layer for the R pixel was 170 nm, the average thickness of the light transmission layer for the G pixel was 144 nm, and the average thickness of the film for the B pixel was 121 nm.
The refractive index n of the semi-transmissive layer (MgAg) was 0.52 for light having a wavelength of 460 nm, 0.57 for light having a wavelength of 530 nm, and 0.67 for light having a wavelength of 610 nm.

2. Evaluation About the light emitting element of each pixel of the example and each comparative example, a constant current of 10 mA / cm ² was passed to each light emitting element using a DC power source, and the luminance of each light emitting element was measured using a luminance meter. The extraction efficiency was determined from the results, and the results are shown in Table 2. Here, the extraction efficiency was determined as the ratio of the luminance of the example and each comparative example with respect to this reference, with the luminance in the color of each pixel of the light emitting element of Comparative Example 1 as the reference (100%).

In addition, with respect to the light-emitting elements of the pixels of the examples and comparative examples, a constant current of 10 mA / cm ² was passed through each light-emitting element using a DC power source, and the emission spectrum at that time was measured. Table 2 shows the full width at half maximum at 610 nm, 530 nm for the G pixel and 460 nm for the B pixel.
As can be seen from Table 2, each pixel of the example has higher luminance than each pixel of each comparative example. In addition, each pixel of the example has a narrow half-value width at the peak of the emission spectrum, and can improve chromaticity. In Comparative Example 2, no resonance effect was obtained due to plasmon absorption of the semi-transmissive layer.

It is typical sectional drawing which shows an example (display apparatus) of the display apparatus containing the light-emitting device obtained by the manufacturing method of the light-emitting device of this invention. It is a figure which shows typically the longitudinal cross-section of the light emitting element with which the light-emitting device shown in FIG. 1 was equipped. 1 is a perspective view showing a configuration of a mobile (or notebook) personal computer to which an electronic apparatus of the present invention is applied. It is a perspective view which shows the structure of the mobile telephone (PHS is also included) to which the electronic device of this invention is applied. It is a perspective view which shows the structure of the digital still camera to which the electronic device of this invention is applied.

Explanation of symbols

1 _B , 1 _G , 1 _R ... Light emitting element 3... Anode 4... Hole injection layer 5... Hole transport layer 6. Layer 9 ... Third light emitting layer 10 ... Electron transport layer 11 ... Electron injection layer 12 ... Cathode 13 ... Transflective layer 14 ... Transparent layer 15 ... Laminated body 19 _B , 19 _G , 19 _R ... ... optical interference transflective portion 100 ... display device 100 _B , 100 _G , 100 _R ... sub-pixel 101 ... light emitting device 102 ... optical interference filter 20 ... substrate 21 ... substrate 22 ... planarization layer 24 ... ... Switching element 241 ... Semiconductor layer 242 ... Gate insulating layer 243 ... Gate electrode 244 ... Source electrode 245 ... Drain electrode 27 ... Conducting part 31 ... Partition wall 32 ... Reflective film 33 ... Corrosion prevention film 34 …… Cathode cover 35 …… Tree Layer 36 …… Light-shielding layer 1100 …… Personal computer 1102 …… Keyboard 1104 …… Main unit 1106 …… Display unit 1200 …… Cellular phone 1202 …… Operation buttons 1204 …… Earpiece 1206 …… Speaker 1300 …… Digital Still camera 1302 …… Case (body) 1304 …… Light receiving unit 1306 …… Shutter button 1308 …… Circuit board 1312 …… Video signal output terminal 1314 …… I / O terminal for data communication 1430 …… TV monitor 1440 …… Personal Computer

Claims (16)

A plurality of semi-transmissive layers having optical transparency;
Each of the semi-transmissive layers has a different refractive index, and has a plurality of light transmissive layers having light transmittance,
A plurality of the semi-transmissive layers and the light-transmissive layers are alternately stacked,
It is configured to repeat light reflection between the interfaces of the semi-transmissive layer and the light transmissive layer, to cause interference, and to emit light having a wavelength according to the distance between the interfaces. ,
Each of the semi-transmissive layers is composed of a metal material obtained by adding an additive metal having an atomic radius different from that of Ag as a main material.   The optical interference filter according to claim 1, wherein a difference between an atomic radius of Ag and an atomic radius of the additive metal is 10% or more of an atomic radius of Ag.   The optical interference filter according to claim 2, wherein the additive metal is any one of Mg, Cu, Zn, and Al, or a combination of two or more thereof.   4. The optical interference filter according to claim 1, wherein the metal material has an Ag content of 80 to 99.9 atomic% and an additive metal content of 0.1 to 20 atomic%. .   The optical interference filter according to claim 1, wherein the semi-transmissive layer is formed by using a vapor phase film forming method.   The optical interference filter according to claim 5, wherein the semi-transmissive layer is formed by co-evaporating Ag and the additive metal.   The optical interference filter according to claim 1, wherein the semi-transmissive layer has a thickness of 1 to 50 nm.   The optical interference filter according to claim 1, wherein a reflectance of the semi-transmissive layer with respect to the light is 20 to 80%.   The light transmissive layer is mainly composed of a metal material obtained by adding an additive metal having a different atomic radius from Ag to Ag so that the refractive index is different from that of the semi-transmissive layer. The optical interference filter according to any one of 8. The light transmission layer, the optical interference filter according to any one of SiO ₂ or SiON claims 1 as a main material 8.   The optical interference filter according to claim 1, wherein the light transmission layer has a thickness of 50 to 300 nm. An optical interference filter according to any one of claims 1 to 11,
A light emitting device having a cathode, an anode, and at least one light emitting layer provided between the cathode and the anode;
A display device configured to emit light from the light emitting element through the optical interference filter.   The display device according to claim 12, wherein the light emitting element has a top emission structure that emits light emitted from the at least one light emitting layer from the cathode side.   The display device according to claim 12 or 13, wherein the at least one light emitting layer includes a plurality of light emitting layers having different emission spectra, and the light emitting layer as a whole emits white light. .   The display device according to claim 14, wherein the at least one light emitting layer includes a red light emitting layer that emits red light, a green light emitting layer that emits green light, and a blue light emitting layer that emits blue light. .   An electronic apparatus comprising the display device according to claim 12.

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