WO2014163116A1

WO2014163116A1 - Organic electroluminescent device

Info

Publication number: WO2014163116A1
Application number: PCT/JP2014/059759
Authority: WO
Inventors: 俊成渡邉; 宮川　直通; 伊藤　和弘; 暁渡邉; 光井　彰
Original assignee: 旭硝子株式会社
Priority date: 2013-04-03
Filing date: 2014-04-02
Publication date: 2014-10-09

Abstract

An organic electroluminescent device which comprises a semiconductor element and an organic electroluminescent element, and which is characterized in that the organic electroluminescent element contains a thin film of an amorphous solid substance that contains calcium, aluminum and oxygen.

Description

Organic electroluminescence device

The present invention relates to an organic electroluminescence device.

Organic electroluminescence devices are widely used for displays, backlights, lighting applications, and the like.

Generally, an organic electroluminescence device has a semiconductor element and an organic electroluminescence element.

The semiconductor element has a role of controlling the operation (on / off, etc.) of the organic electroluminescence element. An organic electroluminescent element has an anode, a cathode, and an organic layer disposed between these electrodes. The organic layer has a light emitting layer.

When a voltage is applied between both electrodes, holes and electrons are injected from each electrode into the light emitting layer. When these holes and electrons are recombined in the light emitting layer, binding energy is generated, and the organic light emitting material in the light emitting layer is excited by this binding energy. Since light is emitted when the excited light emitting material returns to the ground state, a light emitting function can be obtained by using this.

In a normal case, the organic layer further has a hole injection layer and / or a hole transport layer, and an electron injection layer and / or an electron transport layer. The hole injection layer and the hole transport layer are disposed between the anode and the light emitting layer, and have a role of selectively injecting holes into the light emitting layer. The electron injection layer and the electron transport layer are disposed between the cathode and the light emitting layer and have a role of selectively injecting electrons into the light emitting layer. Therefore, by arranging these layers, the light emission efficiency of the organic electroluminescence element can be increased (Patent Document 1).

JP-A-11-102787

In the organic electroluminescence element configured as described above, a material such as lithium fluoride (LiF) is usually used for the electron injection layer.

However, since lithium fluoride is originally an insulating material, in order to use this material as an electron injection layer of an organic electroluminescence device, the thickness of the layer needs to be extremely thin (for example, 0.1 nm to 0.4 nm). However, often it is difficult to form such an extremely thin film. For example, if the film thickness becomes too thin, it becomes difficult to obtain a layered thin film. On the other hand, when the film thickness is thick, an electron injection layer having sufficient conductivity cannot be obtained.

Also, lithium fluoride has a problem that it is relatively unstable and easily deteriorates when exposed to the atmosphere. For this reason, it is necessary to handle the electron injection layer made of lithium fluoride in a controlled environment, and as a result, the manufacturing process becomes complicated.

Furthermore, due to such characteristics of lithium fluoride, when sufficient conductivity is not obtained in the electron injection layer, or when the electron injection layer is deteriorated, the organic electroluminescence element and further the organic electroluminescence device are used. There is a possibility that desired light emission characteristics cannot be obtained or the reliability of the organic electroluminescence device is lowered.

The present invention has been made in view of such a background, and an object of the present invention is to provide an organic electroluminescence device having better stability and higher reliability than conventional ones.

In the present invention,
A semiconductor element;
An organic electroluminescence element;
Have
The organic electroluminescence device includes an organic electroluminescence device including a thin film of an amorphous solid material containing calcium, aluminum, and oxygen.

Here, in the organic electroluminescence device according to the present invention, the organic electroluminescence element has an anode, an organic layer, and a cathode,
The thin film of the amorphous solid material may be included in the organic layer or the cathode.

In the organic electroluminescence device according to the present invention, the thin film of the amorphous solid material may be composed of amorphous C12A7 electride.

In the organic electroluminescence device according to the present invention, the semiconductor element may include a thin film transistor having a semiconductor layer.

In the organic electroluminescence device according to the present invention, the semiconductor layer may include amorphous silicon, polysilicon, single crystal silicon, an oxide semiconductor, or an organic semiconductor.

In the organic electroluminescence device according to the present invention, the oxide semiconductor may include In, Ga, and Zn.

In the organic electroluminescence device according to the present invention, the semiconductor element may have a part of a semiconductor substrate as a semiconductor region.

In the present invention, it is possible to provide an organic electroluminescence device having better stability and higher reliability than conventional ones.

1 is a cross-sectional view schematically illustrating a configuration of an organic electroluminescence device according to an embodiment of the present invention. It is the figure which showed typically the example of 1 structure of the organic electroluminescent element. It is the figure which showed typically the example of another structure of the organic electroluminescent element. It is the figure which showed schematically the wiring circuit of the 1st organic electroluminescent apparatus. It is the schematic diagram which showed the conceptual structure of the amorphous C12A7 electride. It is the figure which showed schematically the flow of the film-forming method of the thin film of an amorphous C12A7 electride. FIG. 3 is a cross-sectional view schematically showing an example of a semiconductor device configured by a top gate structure-top contact method. FIG. 3 is a cross-sectional view schematically showing an example of a semiconductor device configured by a top gate structure-bottom contact method. FIG. 3 is a cross-sectional view schematically showing an example of a semiconductor device configured by a bottom gate structure-top contact method. FIG. 6 is a cross-sectional view schematically showing an example of a semiconductor device configured by a bottom gate structure-bottom contact method. It is sectional drawing which showed schematically the structure of the organic electroluminescent apparatus by another Example of this invention.

Hereinafter, the configuration of the present invention will be described in detail with reference to the drawings.

(About the organic electroluminescence device according to one embodiment of the present invention)
In FIG. 1, the cross section of the organic electroluminescent apparatus (1st organic electroluminescent apparatus) by one Example of this invention is shown typically.

As shown in FIG. 1, the first organic electroluminescence device 1 includes a semiconductor element 100 (see a region surrounded by a square frame in FIG. 1) formed on a substrate 110, and an organic electroluminescence element 200 (FIG. 1). (Refer to the area surrounded by a round frame).

In FIG. 1, the first organic electroluminescence device 1 is shown as an active matrix method, but the first organic electroluminescence device 1 may be a passive matrix method.

In the example of FIG. 1, the first organic electroluminescence device 1 includes a first passivation layer 10 formed on the substrate 110 and a second passivation layer 20 formed on the organic electroluminescence element 200. Have.

The

passivation layers

10 and 20 may be made of an insulator such as silicon oxide (SiO _x ), silicon nitride (SiN _x ), silicon oxynitride (SiO _x N _y ), and ceramics. However, the first and

second passivation layers

10 and 20 may be omitted.

The semiconductor element 100 has a role of controlling the operation of the organic electroluminescence element 200.

The type of the semiconductor element 100 is not particularly limited. The semiconductor element 100 may include, for example, a field effect transistor such as a thin film transistor as shown in FIG.

In the example of FIG. 1, two

thin film transistors

101 and 102 are shown as the semiconductor element 100. The first thin film transistor (driving transistor) 101 includes a semiconductor layer 105, a source electrode 120, a drain electrode 122, and a gate electrode 124. The second thin film transistor (switching transistor) 102 has a similar structure.

On the other hand, the organic electroluminescence element 200 has a lower electrode 210, an organic layer 220, and an upper electrode 230. In a normal case, the organic layer 220 includes a plurality of layers including a light emitting layer.

FIG. 2 schematically shows an example of an enlarged view of the organic electroluminescence element.

As shown in FIG. 2, the organic electroluminescence element 200A has an anode 210a as a lower electrode, an organic layer 220a, and a cathode 230a as an upper electrode.

The organic layer 220a is configured by laminating a hole injection layer 223a, a hole transport layer 224a, a light emitting layer 225a, an electron transport layer 226a, and an electron injection layer 227a in this order from the anode 210a side.

However, the hole injection layer 223a, the hole transport layer 224a, and / or the electron transport layer 226a may be omitted.

Further, the hole injection layer 223a, the hole transport layer 224a, and / or the electron transport layer 226a may not be a layer made of an organic substance. That is, the hole injection layer 223a, the hole transport layer 224a, and / or the electron transport layer 226a may be a layer made of an inorganic material.

Here, when a transparent electrode is used as the anode 210a, the lower side of the organic electroluminescence element 200A is a light extraction surface. Conversely, when a transparent electrode is used as the cathode 230a, the upper side of the organic electroluminescent element 200A is the light extraction surface. Furthermore, when both the anode 210a and the cathode 230a are transparent electrodes, light can be extracted from both the upper side and the lower side.

Such a transparent electrode may be made of a transparent metal oxide such as ITO (indium tin oxide).

FIG. 3 schematically shows another configuration example of the organic electroluminescence element.

As shown in FIG. 3, the organic electroluminescence element 200B has a cathode 210b as a lower electrode, an organic layer 220b, and an anode 230b as an upper electrode.

The organic layer 220b is configured by laminating an electron injection layer 227b, an electron transport layer 226b, a light emitting layer 225b, a hole transport layer 224b, and a hole injection layer 223b in this order from the cathode 210b side.

However, also in this case, the hole injection layer 223b, the hole transport layer 224b, and / or the electron transport layer 226b may be omitted.

Here, when a transparent electrode is used as the cathode 210b, the lower side of the organic electroluminescence element 200B is a light extraction surface. Conversely, when a transparent electrode is used as the anode 230b, the upper side of the organic electroluminescence element 200A is the light extraction surface. Furthermore, when both the cathode 210b and the anode 230b are transparent electrodes, light can be extracted from both the upper side and the lower side.

Here, referring to FIG. 1 again, the organic electroluminescence element 200 (and 200A, 200B; the same applies hereinafter) is disposed on the first and second

thin film transistors

101, 102.

The lower electrode 210 of the organic electroluminescence element 200 is connected to the drain electrode 122 of the first thin film transistor 101.

FIG. 4 schematically shows a wiring circuit of the first organic electroluminescence device 1 shown in FIG.

As shown in FIG. 4, the first organic electroluminescence device 1 includes a gate wiring 320, a data wiring 322, and a driving wiring 324.

The gate wiring 320 is composed of a plurality of wirings parallel to each other. The data wiring 322 is composed of a plurality of wirings parallel to each other. Similarly, the drive wiring 324 includes a plurality of wirings parallel to each other. The gate wiring 220, the data wiring 222, and the drive wiring 324 are electrically insulated from each other.

The gate electrode 124 of the second thin film transistor 102 is connected to the gate wiring 320, and the source electrode 120 of the second thin film transistor 102 is connected to the data wiring 322. The drain electrode 122 of the second thin film transistor 102 is connected to the capacitor 326 and the gate electrode 124 of the first thin film transistor 101. The source electrode 120 of the first thin film transistor 101 is connected to the drive wiring 324, and the drain electrode 122 of the first thin film transistor 101 is connected to the organic electroluminescence element 200.

Here, the first organic electroluminescence device 1 includes a thin film of an amorphous solid material containing calcium, aluminum, and oxygen (hereinafter simply referred to as “amorphous thin film”) in any of the organic electroluminescence elements 200. It has a feature of including.

For example, in the organic electroluminescence element 200, the

organic layers

220, 220a, and 220b may include such an amorphous thin film. For example, in FIG. 2 or FIG. 3, the

electron injection layers

227a and 227b may include amorphous thin films. Alternatively or additionally, in the organic electroluminescent element 200, the

cathodes

230a and 210b in FIG. 2 or 3 may include an amorphous thin film.

In the amorphous thin film, the molar ratio of Al / Ca is preferably 0.5 to 4.7, more preferably 0.6 to 3, and further preferably 0.8 to 2.5. . The composition analysis of the thin film can be performed by XPS method, EPMA method, EDX method or the like.

The amorphous thin film may be an electride of oxide containing calcium and aluminum. The amorphous thin film preferably contains electrons in an electron density range of 2.0 × 10 ¹⁸ cm ^{−3 to} 2.3 × 10 ²¹ cm ⁻³ . The amorphous thin film preferably absorbs light at a photon energy position of 4.6 eV.

An amorphous thin film shows semiconductor electrical characteristics and has a low work function. The work function may be 2.4 to 4.5 eV, or 2.8 to 3.2 eV.

Such an amorphous thin film may be composed of, for example, an amorphous C12A7 electride thin film.

As will be described in detail later, the amorphous C12A7 electride used as the

electron injection layers

227a and 227b of the organic electroluminescence element 200 exhibits good conductivity. Therefore, when amorphous C12A7 electride is used as the

electron injection layers

227a and 227b, it is not necessary to reduce the thickness of the layer to the order of less than nm, unlike the conventional lithium fluoride electron injection layer.

In addition, amorphous C12A7 electride is a stable ceramic material and does not deteriorate or deteriorate even when exposed to the atmosphere. Therefore, when amorphous C12A7 electride is used as the

electron injection layers

227a and 227b, the problem of handling in a controlled environment as in the case of a conventional lithium fluoride electron injection layer is solved. The

Furthermore, amorphous C12A7 electride has a low work function. Therefore, in the organic electroluminescence element 200, it is possible to lower the electron injection barrier from the

cathodes

230a and 210b to the

light emitting layers

225a and 225b, the organic electroluminescence element 200 having high luminous efficiency, and further the first organic electroluminescence. Device 100 can be obtained.

In addition, amorphous C12A7 electride has a large ionization potential. Therefore, amorphous C12A7 electride has a so-called hole blocking effect. That is, holes that have not recombined with electrons in the

light emitting layers

225a and 225b are prevented from passing through the

electron transport layers

226a and 226b and reaching the

cathodes

230a and 210b, and the recombination probability of electrons and holes is increased. Therefore, in this invention, an organic EL element with high luminous efficiency can be obtained.

The same effect can be obtained when an amorphous C12A7 electride thin film is used as the

cathodes

230a and 210b of the organic electroluminescence element 200.

Due to such features, the first organic electroluminescence device 100 is unlikely to have a reduced reliability or a desired light emission characteristic unlike the conventional organic electroluminescence device, and handling is difficult. It is possible to provide an organic electroluminescence device that is easy and reliable.

In the following description, each configuration and feature will be described assuming that the amorphous thin film is an amorphous C12A7 electride thin film.

(Term definition)
Here, in this invention, the amorphous C12A7 electride contained in an organic electroluminescent element, and the term relevant to this are demonstrated.

(Crystalline C12A7)
In the present application, “crystalline C12A7” means a crystal of 12CaO · 7Al ₂ O ₃ and an isomorphous compound having a crystal structure equivalent to this. The mineral name of this compound is “mayenite”.

The crystalline C12A7 in the present invention is a compound in which some or all of Ca atoms and / or Al atoms in the C12A7 crystal skeleton are substituted with other atoms within a range in which the cage structure formed by the skeleton of the crystal lattice is maintained. In addition, the same type compound may be used in which some or all of the free oxygen ions in the cage are replaced with other anions. Incidentally, C12A7 _is sometimes denoted as Ca _{12 Al} 14 _{O 33} or _Ca 24 _Al 28 _{O 66.}

Examples of the isomorphous compound include, but are not limited to, the following compounds (1) to (5).
(1) Isomorphic compounds in which some or all of the Ca atoms in the crystal are substituted with metal atoms such as Sr, Mg, and / or Ba. For example, a compound in which some or all of Ca atoms are substituted with Sr is strontium aluminate Sr ₁₂ Al ₁₄ O ₃₃ , and calcium strontium aluminum is used as a mixed crystal in which the mixing ratio of Ca and Sr is arbitrarily changed. Nate Ca _12-x Sr _X Al ₁₄ O ₃₃ (x is an integer of 1 to 11; in the case of an average value, it is a number greater than 0 and less than 12)
(2) A homomorphic compound in which some or all of the Al atoms in the crystal are substituted with one or more atoms selected from the group consisting of Si, Ge, Ga, In, and B. For _example, like _{_{_{Ca 12 Al 10 Si 4 O 35}}} .
(3) A part of metal atoms and / or nonmetal atoms (excluding oxygen atoms) in the 12CaO.7Al ₂ O ₃ crystal (including the compounds of (1) and (2) above) is Ti, One or more transition metal atoms or typical metal atoms selected from the group consisting of V, Cr, Mn, Fe, Co, Ni, and Cu, alkali metal atoms such as Li, Na, and K, or Ce, Pr, Nd , Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. The same type compound substituted with one or more rare earth atoms selected from the group consisting of Yb.
(4) A compound in which some or all of the free oxygen ions included in the cage are replaced with other anions. Other anions include, for example, one or more selected from the group consisting of H ⁻ , H ₂ ⁻ , H ²⁻ , O ⁻ , O ₂ ⁻ , OH ⁻ , F ⁻ , Cl ⁻ , and S ²⁻ . There are anions and nitrogen (N) anions.
(5) A compound in which part of oxygen in the cage skeleton is substituted with nitrogen (N) or the like.

(Crystalline C12A7 electride)
In the present application, the “crystalline C12A7 electride” means that in the above-mentioned “crystalline C12A7”, free oxygen ions included in the cage (in the case of having other anions included in the cage, the anions) ) Means a compound in which part or all of them are substituted with electrons.

In the crystalline C12A7 electride, the electrons included in the cage are loosely bound in the cage and can move freely in the crystal. For this reason, crystalline C12A7 electride shows electroconductivity. In particular, crystalline C12A7 in which all free oxygen ions are replaced with electrons may be expressed as [Ca ₂₄ Al ₂₈ O ₆₄ ] ⁴⁺ (4e ⁻ ).

(Amorphous C12A7 electride)
In the present application, “amorphous C12A7 electride” means an amorphous solid substance having a composition equivalent to that of crystalline C12A7 electride, consisting of solvation having amorphous C12A7 as a solvent and electrons as a solute. means.

FIG. 5 conceptually shows the structure of the amorphous C12A7 electride.

Generally, in the crystalline C12A7 electride, each cage shares a plane and is three-dimensionally stacked to form a crystal lattice, and electrons are included in a part of these cages. In contrast, in the case of amorphous C12A7 electride, as shown in FIG. 5, a characteristic partial structure called bipolaron 550 is present in a dispersed state in a solvent 520 made of amorphous C12A7. . The bipolarlon 550 is configured such that two cages 530 are adjacent to each other, and an electron (solute) 540 is included in each cage 530. However, the state of the amorphous C12A7 electride is not limited to the above, and two electrons (solutes) 540 may be included in one cage 530. Further, a plurality of these cages may be aggregated, and the aggregated cage can be regarded as a microcrystal. Therefore, a state in which the microcrystal is included in the amorphous is also regarded as amorphous in the present invention.

Amorphous C12A7 electride exhibits electrical conductivity and has a low work function. The work function may be 2.4 to 4.5 eV, or 3 to 4 eV. The work function of the amorphous C12A7 electride is preferably 2.8 to 3.2 eV. Amorphous C12A7 electride has a high ionization potential. The ionization potential may be 7.0 to 9.0 eV, or 7.5 to 8.5 eV.

Bipolarlon 550 has almost no light absorption in the range of visible light with a photon energy of 1.55 eV to 3.10 eV, and shows light absorption in the vicinity of 4.6 eV. Therefore, the amorphous C12A7 electride thin film is transparent in visible light. Further, by measuring the light absorption characteristics of the sample to be inspected and measuring the light absorption coefficient in the vicinity of 4.6 eV, whether or not the bipolaron 550 is present in the sample, that is, the sample is amorphous C12A7 elect You can check if you have a ride.

Further, two adjacent cages 530 constituting the bipolaron 550 are Raman-active, and show a characteristic peak in the vicinity of 186 cm ^{−1 in the} Raman spectroscopic measurement.

(C12A7 electride)
In the present application, “C12A7 electride” means a concept including both the above-mentioned “crystalline C12A7 electride” and “amorphous C12A7 electride”.

“Crystalline C12A7 electride” includes Ca atoms, Al atoms, and O atoms, the molar ratio of Ca: Al is in the range of 13:13 to 11:15, and the molar ratio of Ca: Al is 12 It is preferably in the range of 5: 13.5 to 11.5: 14.5, and more preferably in the range of 12.2: 13.8 to 11.8: 14.2.

The “amorphous C12A7 electride” includes Ca atoms, Al atoms, and O atoms, and the molar ratio of Ca: Al is in the range of 13:12 to 11:16. The molar ratio of Ca: Al is 13:13 to 11:15 is preferable, and 12.5: 13.5 to 11.5: 14.5 is more preferable. Further, the thin film of “amorphous C12A7 electride” is composed of Ca, Al, and O in the above composition range at 67% or more, preferably 80% or more, more preferably 95% or more of the whole. preferable.

(About the structure of each layer of the organic electroluminescence element 100)
Next, the structure of each layer which comprises the organic electroluminescent element 200 shown in FIG. 1 is demonstrated in detail. In the following description, for the sake of clarity, the reference numerals attached to the constituent members of the organic electroluminescence element 200A shown in FIG.

(Anode 210a)
As the anode 210a, a metal or a metal oxide is usually used. The material used preferably has a work function of 4 eV or more. As described above, when the light extraction surface of the organic electroluminescence element 200A is on the anode 210a side, the anode 210a needs to be transparent.

The anode 210a may be a metal material such as aluminum, silver, tin, gold, carbon, iron, cobalt, nickel, copper, zinc, tungsten, vanadium, and alloys thereof. Alternatively, the anode 210a is made of, for example, ITO, antimony oxide (Sb ₂ O ₃ ), zirconium oxide (ZrO ₂ ), tin oxide (SnO ₂ ), zinc oxide (ZnO), IZO (Indium Zinc Oxide), AZO (ZnO—Al ₂ O ₃ : zinc oxide doped with aluminum), GZO (ZnO—Ga ₂ O ₃ : zinc oxide doped with gallium), Nb-doped TiO ₂ , Ta-doped TiO ₂ , and IWZO It may also be a metal oxide material such as (In ₂ O ₃ —WO ₃ —ZnO: indium oxide doped with tungsten trioxide and zinc oxide).

The film forming method of the anode 210a is not particularly limited. The anode 210a may be formed by a known film forming technique such as a vapor deposition method, a sputtering method, or a coating method.

Typically, the thickness of the anode 210a is in the range of 2 nm to 150 nm, and when the metal material is used as the transparent electrode, the thickness of the anode 120 is preferably in the range of 2 nm to 50 nm.

The structure of the anode 230b in FIG.

(Hole injection layer 223a)
The hole injection layer 223a is selected from materials having hole injection properties.

The hole injection layer 223a may be an organic material such as CuPc and starburst amine. Alternatively, the hole injection layer 223a may be a metal oxide material, for example, an oxide including at least one metal selected from molybdenum, tungsten, rhenium, vanadium, indium, tin, zinc, gallium, titanium, and aluminum. good.

In general, when the upper electrode formed on the organic layer is formed by sputtering, it is known that the characteristics of the organic EL element deteriorate due to sputtering damage of the organic layer. Since sputtering resistance is higher than that of the material, sputtering damage to the organic layer can be reduced by forming a metal oxide film over the organic material.

In addition, various known materials can be used as the hole injection layer 223a. Note that the hole injection layer 223a may be omitted.

The film forming method of the hole injection layer 223a is not particularly limited. The hole injection layer 223a may be formed by a dry process such as an evaporation method or a transfer method. Alternatively, the hole injection layer 223a may be formed by a wet process such as a spin coating method, a spray coating method, or a gravure printing method.

Typically, the thickness of the hole injection layer 223a is in the range of 1 nm to 50 nm.

The configuration of the hole injection layer 223b in FIG.

(Hole transport layer 224a)
The hole transport layer 224a is selected from materials having hole transport properties.

The hole transport layer 224a may be, for example, an arylamine compound, an amine compound containing a carbazole group, and an amine compound containing a fluorene derivative. Specifically, the hole transport layer 224a includes 4,4′-bis [N- (naphthyl) -N-phenyl-amino] biphenyl (α-NPD), N, N′-bis (3-methylphenyl)- (1,1′-biphenyl) -4,4′-diamine (TPD), 2-TNATA, 4,4 ′, 4 ″ -tris (N- (3-methylphenyl) N-phenylamino) triphenylamine ( MTDATA), 4,4′-N, N′-dicarbazole biphenyl (CBP), spiro-NPD, spiro-TPD, spiro-TAD, TNB, and the like.

In addition, various known materials can be used as the hole transport layer 224a. Note that the hole transport layer 224a may be omitted.

The hole transport layer 224a can be formed using a conventional general film formation process.

Typically, the thickness of the hole transport layer 224a is in the range of 1 nm to 100 nm.

The structure of the hole transport layer 224b in FIG.

(Light emitting layer 225a)
The light emitting layer 225a may be made of any material known as a light emitting material for a general organic electroluminescence element.

The light-emitting layer 225a includes, for example, epidridine, 2,5-bis [5,7-di-t-pentyl-2-benzoxazolyl] thiophene, 2,2 '-(1,4-phenylenedivinylene) bisbenzo Thiazole, 2,2 ′-(4,4′-biphenylene) bisbenzothiazole, 5-methyl-2- {2- [4- (5-methyl-2-benzoxazolyl) phenyl] vinyl} benzoxazole, 2,5-bis (5-methyl-2-benzoxazolyl) thiophene, anthracene, naphthalene, phenanthrene, pyrene, chrysene, perylene, perinone, 1,4-diphenylbutadiene, tetraphenylbutadiene, coumarin, acridine, stilbene, 2- (4-biphenyl) -6-phenylbenzoxazole, aluminum trisoxine, magne Umbisoxin, bis (benzo-8-quinolinol) zinc, bis (2-methyl-8-quinolinolalt) aluminum oxide, indium trisoxin, aluminum tris (5-methyloxin), lithium oxine, gallium trisoxin, calcium bis ( 5-chlorooxin), polyzinc-bis (8-hydroxy-5-quinolinolyl) methane, dilithium epindridione, zinc bisoxin, 1,2-phthaloperinone, 1,2-naphthaloperinone, and the like.

In addition, various known materials can be used for the light emitting layer 225a.

The light emitting layer 225a may be formed by a dry process such as an evaporation method or a transfer method. Alternatively, the light-emitting layer 225a may be formed by a wet process such as a spin coating method, a spray coating method, or a gravure printing method.

Typically, the thickness of the light emitting layer 225a is in the range of 1 nm to 100 nm. The light emitting layer 225a may also be used as a hole transport layer or an electron transport layer.

The configuration of the light emitting layer 225b in FIG.

(Electron transport layer 226a)
Normally, the electron transport layer 226a is made of an organic material such as tris (8-quinolinolato) aluminum (Alq3). In general, however, organic materials such as Alq3 can easily degrade when exposed to air.

For this reason, it is preferable to use a metal oxide material as the electron transport layer 226a.

Examples of the metal oxide material for the electron transport layer 226a include xZnO— (1-x) SiO ₂ (x = 0.5 to 0.9 is preferable), xIn ₂ O ₃ — (1-x) SiO _2. (Preferably x = 0.4 to 0.8), xSnO ₂ — (1-x) SiO ₂ (preferably x = 0.4 to 0.8), ZnO, In—Ga—Zn—O (In: Ga: Zn: O = 1 to 4: 1: 1: 1 are preferred), In—Zn—O, Zn—Mg—O, Zn—Mg—Ga—O, SnO _{2 and the} like.

These metal oxide materials may be in an amorphous form, in a crystalline form, or in a mixed phase of an amorphous and crystalline phase.

In particular, the metal oxide material is preferably in an amorphous form. This is because an amorphous metal oxide material can easily provide a relatively flat film.

The electron affinity of these metal oxide materials is preferably 2.8 to 5.0 eV, more preferably 3.0 to 4.0 eV, and further preferably 3.1 to 3.5 eV. preferable. When the electron affinity is 2.8 eV or more, the electron injection characteristics are high, and the light emission efficiency of the organic electroluminescence element is improved. Further, when the electron affinity is 5.0 eV or less, it is easy to obtain sufficient light emission from the organic electroluminescence element.

When these metal oxide materials are used as the electron transport layer 226a, the effect of improving the stability of the layer and facilitating handling can be obtained as compared with the case of using an organic material such as Alq3.

Also, the Alq3 material has a property of relatively high hole mobility. On the other hand, any of the aforementioned metal oxide materials has a relatively small hole mobility and can selectively transport only electrons. For this reason, when these metal oxide materials are used as the electron transport layer 226a, it becomes possible to further increase the light emission efficiency of the organic electroluminescence element.

The thickness of the electron transport layer 226a made of these metal oxide materials may be 1 nm to 2000 nm, preferably 100 nm to 2000 nm, more preferably 200 nm to 1000 nm, and 300 nm to 500 nm. More preferably. Compared with a normal organic electron transport layer such as Alq3, the above metal oxide material has an electron mobility of 1 to 10 cm ² V ⁻¹ s ⁻¹ and is several orders of magnitude larger. Is possible. Moreover, by setting it as such thickness, compared with the case where an organic electron carrying layer is used, it is possible to suppress the short circuit of an organic electroluminescent element. When the thickness of the inorganic electron transport layer exceeds 2000 nm, it takes a long time to produce a thin film, and thus the produced organic electroluminescence element is expensive.

The method for forming the electron transport layer 226a is not particularly limited. In the case of forming a metal oxide material as described above, for example, a known film formation technique such as a vapor deposition method, a sputtering method, or a coating method may be used.

Note that the electron transport layer 160 may be omitted.

The configuration of the electron transport layer 226b in FIG.

(Electron injection layer 227a)
As described above, amorphous C12A7 electride may be used for the electron injection layer 227a.

The thickness of the conventional electron injection layer 227a is, for example, in the range of 0.1 nm to 0.4 nm. This is because, as described above, LiF that has been conventionally used as an electron injection layer has high resistance and cannot be used as a conductive member unless it is made extremely thin.

On the other hand, since the electron injection layer 227a made of amorphous C12A7 electride has conductivity, there is no restriction on the film thickness. Therefore, the electron injection layer 227a having a relatively uniform thickness can be formed relatively easily.

The electron injection layer 227a made of amorphous C12A7 electride has a thickness in the range of about 1 nm to 50 nm, for example. It may be 30 nm or less, or 20 nm or less. It may be 2 nm or more, 4 nm or more, or 9 nm or more.

As described above, amorphous C12A7 electride is a ceramic material and is stable without being altered even when exposed to the atmosphere. Therefore, when amorphous C12A7 electride is used as the electron injection layer 227a, the problem that handling must be performed in a controlled environment like a conventional lithium fluoride electron injection layer is solved. As a result, it is possible to obtain an organic electroluminescence element 200A that is easy to handle and highly reliable.

The structure of the electron injection layer 227b in FIG.

(Cathode 230a)
The cathode 230a is usually made of a metal material.

The cathode 230a may be, for example, aluminum, silver, gold, magnesium, calcium, titanium, yttrium, lithium, gadolinium, ytterbium, ruthenium, manganese, molybdenum, vanadium, chromium, tantalum, and alloys thereof. Alternatively, the cathode 230a is formed of, for example, ITO, antimony oxide (Sb ₂ O ₃ ), zirconium oxide (ZrO ₂ ), tin oxide (SnO ₂ ), zinc oxide (ZnO), IZO (Indium Zinc Oxide), AZO (ZnO—Al ₂ O ₃ : zinc oxide doped with aluminum), GZO (ZnO—Ga ₂ O ₃ : zinc oxide doped with gallium), Nb-doped TiO ₂ , Ta-doped TiO ₂ , and IWZO It may also be a metal oxide material such as (In ₂ O ₃ —WO ₃ —ZnO: indium oxide doped with tungsten trioxide and zinc oxide).

The film formation method of the cathode 230a is not particularly limited. The cathode 230a may be formed by, for example, a vapor deposition method (vacuum vapor deposition method, electron beam vapor deposition method), an ion plating method, a laser ablation method, a sputtering method, or the like.

Typically, the thickness of the cathode 230a is in the range of 2 nm to 150 nm. When a metal material is used as the transparent electrode, the thickness of the cathode 230a is preferably in the range of 2 nm to 50 nm.

As described above, the cathode 230a may be formed of an amorphous C12A7 electride thin film.

The configuration of the cathode 210b in FIG. 3 is also described in the same manner as described above.

(Film formation method of electron injection layer 227a)
Here, an example of a method for forming a thin film of amorphous C12A7 electride for the electron injection layer 227a will be described. Note that when the cathode 230a is formed of an amorphous C12A7 electride thin film, the cathode 230a can also be formed by a similar method.

FIG. 6 schematically shows a flow of a method for forming a thin film of amorphous C12A7 electride.

As shown in FIG. 6, the method for forming a thin film of amorphous C12A7 electride is as follows:
Preparing a target of crystalline C12A7 electride having an electron density of 2.0 × 10 ¹⁸ cm ⁻³ to 2.3 × 10 ²¹ cm ⁻³ (S110);
A step of forming a film on the cathode or the electron transport layer by a vapor deposition method in an atmosphere having an oxygen partial pressure of less than 0.1 Pa using the target (S120);
Have

Hereinafter, each process will be described in detail.

(Process S110)
First, a deposition target used in the subsequent step S120 is prepared.

The target is composed of crystalline C12A7 electride.

The method for producing the target made of crystalline C12A7 electride is not particularly limited. The target may be manufactured using, for example, a conventional method for manufacturing a bulk crystalline C12A7 electride. For example, a crystalline C12A7 sintered body is heat-treated at about 1150 to 1460 ° C., preferably about 1200 to 1400 ° C. in the presence of a reducing agent such as Ti, Al, Ca, or C. A target made of C12A7 electride may be manufactured. A green compact formed by compressing a crystalline C12A7 powder may be used as a target. A crystalline C12A7 sintered body is effectively heat-treated at 1230 to 1415 ° C. in the presence of carbon and metallic aluminum while keeping the sintered body and metallic aluminum in contact with each other. A target made of quality C12A7 electride can be produced. In the present invention, the area of the main surface is preferably 1900 mm ² or more, more preferably 4400mm ² or more, more preferably 7800mm ² or more, particularly preferably can be used, for example at 31400Mm ² or more. In the present invention, a target having a thickness of preferably 2 to 15 mm, more preferably 2.5 to 13 mm, still more preferably 3 to 10 mm, and particularly preferably 3 to 8 mm can be used.

In the flat target of a disc, the diameter is preferably 50 mm or more, more preferably 75 mm or more, further preferably 100 mm or more, and particularly preferably 200 mm or more. In the rectangular flat target, the diameter of the long side is preferably 50 mm or more, more preferably 75 mm or more, further preferably 100 mm or more, and particularly preferably 200 mm or more. In the cylindrical target, the height of the cylinder is preferably 50 mm or more, more preferably 75 mm or more, further preferably 100 mm or more, and particularly preferably 200 mm or more.

Here, the electron density of the target, that is, crystalline C12A7 electride is in the range of 2.0 × 10 ¹⁸ cm ⁻³ to 2.3 × 10 ²¹ cm ⁻³ . The electron density of the crystalline C12A7 electride is preferably 1 × 10 ¹⁹ cm ⁻³ or more, more preferably 1 × 10 ²⁰ cm ⁻³ or more, further preferably 5 × 10 ²⁰ cm ⁻³ or more, and 1 × 10 ²¹ cm ⁻³ or more is particularly preferable. The higher the electron density of the crystalline C12A7 electride constituting the target, the easier it is to obtain an amorphous C12A7 electride having a lower work function. In particular, in order to obtain an amorphous C12A7 electride having a work function of 3.0 eV or less, the electron density of the crystalline C12A7 electride is more preferably 1.4 × 10 ²¹ cm ⁻³ or more, and 1.7 × 10 ²¹ cm ⁻³ or more is more preferable, and 2 × 10 ²¹ cm ⁻³ or more is particularly preferable. In particular, when all the free oxygen ions (or other anions when they have other anions) are replaced with electrons, the electron density of the crystalline C12A7 electride is 2.3 × 10 ²¹ cm ⁻³ . When the electron density of the crystalline C12A7 electride is less than 2.0 × 10 ¹⁸ cm ⁻³ , the electron density of the amorphous C12A7 electride thin film obtained by film formation becomes small.

In addition, the electron density of C12A7 electride can be measured by the iodine titration method.

In this iodine titration method, a C12A7 electride sample was immersed in a 5 mol / l iodine aqueous solution and dissolved by adding hydrochloric acid, and then the amount of unreacted iodine contained in this solution was titrated with sodium thiosulfate. It is a method of detection. In this case, due to dissolution of the sample, iodine in the aqueous iodine solution is ionized by the following reaction:

I ₂ + e ⁻ → 2I ⁻ (1) Formula
When titrating an aqueous iodine solution with sodium thiosulfate,

2Na ₂ S ₂ O ₃ + I ₂ → 2NaI + Na ₂ S ₄ O ₆ (2) Formula
By this reaction, unreacted iodine is changed to sodium iodide. By subtracting the amount of iodine detected by titration from equation (2) from the amount of iodine present in the initial solution, the amount of iodine consumed in the reaction of equation (1) is calculated. Thereby, the electron density in the sample of C12A7 electride can be measured. The iodine titration method can be applied regardless of whether the C12A7 electride is crystalline or amorphous.

The electron density of the crystalline C12A7 electride can be measured by a light absorption measurement method. Since the crystalline C12A7 electride has a specific light absorption around 2.8 eV, the electron density can be determined by measuring the absorption coefficient. In particular, when the sample is a sintered body, it is convenient to use the diffuse reflection method after pulverizing the sintered body into a powder.

The obtained target is used as a raw material source when an amorphous C12A7 electride thin film is formed in the next step.

Note that the surface of the target may be polished by mechanical means before use.

Generally, a bulk body of crystalline C12A7 electride obtained by a conventional method may have a very thin film (foreign matter) on the surface. When a film forming process is performed using a target having such a film formed on the surface as it is, the composition of the obtained thin film may deviate from a desired composition ratio. However, such a problem can be significantly suppressed by carrying out the polishing treatment of the target surface.

(Process S120)
Next, film formation is performed on the electron transport layer by a vapor deposition method using the target prepared in the above-described step S110.

In the present application, “vapor deposition” refers to vapor deposition of a target material including a physical vapor deposition (PVD) method, a PLD method, a sputtering method, and a vacuum deposition method, and then depositing this material on a substrate. This is a general term for film formation methods.

Among the “vapor deposition methods”, the sputtering method is particularly preferable. In the sputtering method, a thin film can be formed relatively uniformly in a large area. The sputtering method includes a DC (direct current) sputtering method, a high frequency sputtering method, a helicon wave sputtering method, an ion beam sputtering method, a magnetron sputtering method, and the like.

Hereinafter, the process S120 will be described by taking as an example the case where film formation is performed by a sputtering method.

The temperature of the deposition target substrate when forming a thin film of amorphous C12A7 electride is not particularly limited, and any temperature in the range of room temperature to, for example, 700 ° C. may be adopted. It should be noted that when depositing a thin film of amorphous C12A7 electride, it is not necessary to “positively” heat the substrate. However, there may be a case where the temperature of the deposition target substrate rises “incidentally” due to the radiant heat of the vapor deposition source. For example, the temperature of the deposition target substrate may be 500 ° C. or lower, or 200 ° C. or lower.

The oxygen partial pressure during film formation is less than 0.1 Pa. The oxygen partial pressure is preferably 0.05 Pa or less, preferably 0.01 Pa or less, more preferably 1 × 10 ⁻³ Pa or less, and preferably 1 × 10 ⁻⁴ Pa or less. More preferably, it is particularly preferably 1 × 10 ⁻⁵ Pa or less. When the oxygen partial pressure is 0.1 Pa or more, oxygen is taken into the deposited thin film, which may reduce the electron density.

On the other hand, the hydrogen partial pressure during film formation is preferably less than 0.004 Pa. If it is 0.004 Pa or more, hydrogen or OH component is taken into the formed thin film, and the electron density of the amorphous C12A7 electride thin film may be lowered.

The sputtering gas used is not particularly limited. The sputtering gas may be an inert gas or a rare gas. The inert gas, eg, N ₂ gas. In addition, examples of the rare gas include He (helium), Ne (neon), Ar (argon), Kr (krypton), and Xe (xenon). These may be used alone or in combination with other gases. Alternatively, the sputtering gas may be a reducing gas such as NO (nitrogen monoxide).

The pressure of the sputtering gas (pressure in the chamber) is not particularly limited, and can be freely selected so that a desired thin film can be obtained. In particular, the pressure P (Pa) of the sputtering gas (pressure in the chamber) is such that when the distance between the substrate and the target is t (m) and the diameter of the gas molecule is d (m),

8.9 × 10 ⁻²² / (td ² ) <P <4.5 × 10 ⁻²⁰ / (td ² ) (3) Formula
It may be selected to satisfy. In this case, the mean free path of the sputtered particles becomes substantially equal to the distance between the target and the substrate, and the sputtered particles are suppressed from reacting with the remaining oxygen. In this case, as a sputtering method apparatus, it is possible to use an inexpensive and simple vacuum apparatus having a relatively high back pressure.

Through the above steps, an amorphous C12A7 electride thin film for the cathode 230a and / or the electron injection layer 227a can be formed.

In addition, it can confirm that the obtained thin film has a composition of C12A7 by the composition analysis of a thin film. For example, it is possible to evaluate whether the thin film has a composition of C12A7 by measuring the Ca / Al ratio of the thin film by XPS method, EPMA method, EDX method or the like. Analysis by the XPS method is possible when the film thickness is 100 nm or less, EPMA method when the film thickness is 100 nm or more, and EDX method when it is 3 μm or more. In addition, as described above, it is confirmed that the thin film is an amorphous C12A7 electride by measuring the light absorption characteristics of the sample and determining the presence or absence of light absorption near the photon energy of 4.6 eV. Can do.

When the film thickness is relatively large, it is confirmed whether or not the thin film is amorphous C12A7 electride by determining the presence or absence of a characteristic peak in the vicinity of 186 cm ⁻¹ in Raman spectroscopic measurement. Can do.

In the above, the method of forming an amorphous C12A7 electride thin film has been briefly described by taking the sputtering method as an example. However, the method for forming the amorphous C12A7 electride thin film is not limited to this, and the above-described two steps (steps S110 and S120) may be appropriately changed, or various steps may be added. It is clear.

For example, in the above-described step S120, a pre-sputtering process (a target dry etching process) may be performed on the target before starting the film formation of the amorphous C12A7 electride by the sputtering method.

By performing the pre-sputtering process, the surface of the target is cleaned, and it becomes easy to form a thin film having a desired composition in the subsequent film formation process (main film formation).

For example, when the target is used for a long time, oxygen is taken into the surface of the target, and the electron density of the crystalline C12A7 electride constituting the target may decrease. When such a target is used, there is a possibility that the electron density is lowered even in the formed thin film. Further, when the target is used for a long time, the composition of the target may deviate from the initial composition due to the difference in sputtering rate of each component constituting the target (ie, crystalline C12A7 electride). When such a target is used, the composition may deviate from a desired value even in the formed thin film.

However, such a problem is suppressed by performing the pre-sputtering process. The pre-sputtering process may be performed, for example, before performing a new film formation or whenever the target usage time reaches a predetermined value.

Note that the gas used in the pre-sputtering process may be the same as or different from the sputtering gas used in the main film formation.

In particular, the gas used for the pre-sputtering process is preferably He (helium), Ne (neon), N ₂ (nitrogen), Ar (argon), and / or NO (nitrogen monoxide).

In addition, various changes in steps S110 and S120 and addition of new steps are possible.

The amorphous C12A7 electride thin film formed by such a method has an electron density in the range of 2.0 × 10 ¹⁸ cm ^{−3 to} 2.3 × 10 ²¹ cm ⁻³ . It exhibits light absorption at a photon energy position of 6 eV. The electron density is more preferably 1 × 10 ¹⁹ cm ⁻³ or more, and further preferably 1 × 10 ²⁰ cm ⁻³ or more. The light absorption value at a position of 4.6 eV may be 100 cm ⁻¹ or more. It may be 200 cm ⁻¹ or more.

The electron density of the amorphous C12A7 electride thin film can be measured by the above-mentioned iodine titration method. Incidentally, in the amorphous C12A7 electride thin film, the density of the bipolaron can be calculated by halving the measured electron density.

The thin film of amorphous C12A7 electride has conductivity due to hopping conduction of electrons in the cage. The DC conductivity at room temperature of the amorphous C12A7 electride thin film may be 10 ⁻⁹ to 10 ⁻¹ S · cm ⁻¹ , and 10 ⁻⁷ to 10 ⁻³ S · cm ^{−. 1} may be sufficient.

In addition to the bipolaron 74, the amorphous C12A7 electride thin film may have, as a partial structure, an F ⁺ center in which one electron is captured in an oxygen vacancy. The F ⁺ center is configured by a plurality of Ca ²⁺ ions surrounded by one electron and does not have a cage. The F ⁺ center has light absorption in the visible light range of 1.55 eV to 3.10 eV centered on 3.3 eV.

When the concentration of F ⁺ center is less than 5 × 10 ¹⁸ cm ⁻³ , the transparency of the thin film is increased, which is preferable. The concentration of the F ⁺ center is more preferably 1 × 10 ¹⁸ cm ⁻³ or less, and further preferably 1 × 10 ¹⁷ cm ⁻³ or less. Note that the concentration of the F ⁺ center can be measured by a signal intensity having a g value of 1.998 in ESR.

In the amorphous C12A7 electride thin film, the ratio of the light absorption coefficient at a position of 3.3 eV to the light absorption coefficient at a photon energy position of 4.6 eV may be 0.35 or less.

Moreover, since the amorphous C12A7 electride thin film does not have a crystal grain boundary, it has excellent flatness. The root mean square roughness (RMS) of the surface of the amorphous C12A7 electride thin film may be 0.1 to 10 nm, and preferably 0.2 to 5 nm. When the electron injection layer 227a and / or the cathode 230a is formed of an amorphous C12A7 electride thin film having an RMS of 2 nm or less, the characteristics of the organic electroluminescent element 200A are more preferable. Further, when the RMS is 10 nm or more, the characteristics of the organic electroluminescence element 200A may be deteriorated, so that it is necessary to add a polishing process or the like. RMS can be measured using, for example, an atomic force microscope.

The composition of the amorphous C12A7 electride thin film may be different from the stoichiometric ratio of C12A7, or may be different from the composition ratio of the target used in the production.

The organic electroluminescence element 200 may have any of the following configurations.
(1) The substrate, the anode, and the cathode are arranged in this order, and the substrate side is the light extraction surface, and an amorphous thin film exists between the anode and the cathode, or constitutes the cathode.
(2) The substrate, the anode, and the cathode are arranged in this order, and the cathode side is the light extraction surface, and an amorphous thin film exists between the anode and the cathode or constitutes the cathode.
(3) A substrate, a cathode, and an anode are provided in this order, and the substrate side is a light extraction surface, and an amorphous thin film exists between the anode and the cathode, or constitutes the cathode.
(4) A substrate, a cathode, and an anode are provided in this order, and the anode side is a light extraction surface, and an amorphous thin film exists between the anode and the cathode or constitutes the cathode.
In any of the above (1) to (4), it is preferable that the amorphous thin film exists between the cathode and the light emitting layer existing between the cathode and the anode.

(About the semiconductor element 100)
Next, the semiconductor element 100 will be briefly described.

(Substrate 110)
The material of the substrate 110 on which the semiconductor element 100 is disposed is not particularly limited. However, when the light extraction surface of the organic electroluminescence device 1 is the substrate 110 side, the substrate 110 is made of a transparent material.

As the transparent material, for example, a glass substrate, a plastic substrate, a resin substrate, or the like can be used.

(Semiconductor layer 105)
The material of the semiconductor layer 105 constituting the semiconductor element 100 is not particularly limited. The semiconductor layer 105 may be made of a general semiconductor material such as amorphous silicon, polysilicon, single crystal silicon, oxide semiconductor, or organic semiconductor.

Examples of the oxide semiconductor include oxides of transition metals such as In, Ti, Nb, Sn, Zn, Gd, Cd, Zr, Y, La, and Ta, SrTiO ₃ , CaTiO ₃ , ZnO · Rh ₂ O _3. , CuGaO ₂ , and oxides such as SrCu ₂ O ₂ .

For example, the oxide semiconductor may include at least one oxide of In, Sn, Zn, Ga, and Cd. The oxide semiconductor preferably includes at least one oxide of In, Sn, Zn, and Ga, and includes an oxide including at least one of In, Ga, and Zn (eg, an In—O-based oxide). ) Is more preferable.

For example, the oxide semiconductor may include at least two of In, Ga, and Zn, for example, all oxides.

Examples of such oxide semiconductors include IGZO (In—Ga—Zn—O), ITO (In—Sn—O), ISZO (In—Si—Zn—O), IGO (In—Ga—O), ITZO (In—Sn—Zn—O), IZO (In—Zn—O), IHZO (In—Hf—Zn—O), and the like. A film formed using such an oxide semiconductor may be amorphous, crystalline, or in a state containing amorphous and crystalline.

Note that the semiconductor element 100 in the first organic electroluminescence device 1 shown in FIG. 1, that is, the

thin film transistors

101 and 102, is configured by a so-called top gate structure-top contact method. However, the arrangement structure of the thin film transistors is not limited to this.

Here, for example, (i) top gate structure-top contact system, (ii) top gate structure-bottom contact system, (iii) bottom gate structure-top contact system, and (iii) There is a bottom gate structure-bottom contact system.

These arrangement structures will be briefly described with reference to FIGS.

First, FIG. 7 shows an example of a semiconductor device configured by a top gate structure-top contact method.

7, the semiconductor element 700 formed over the substrate 710 includes a semiconductor layer 705, a source electrode 720 and a drain electrode 722, a gate insulating layer 730, and a gate electrode 724.

In this example, the gate electrode 724 is disposed on the semiconductor layer 705 (top gate structure), and the source electrode 720 and the drain electrode 722 are also disposed on the semiconductor layer 705 (top contact method).

Next, FIG. 8 shows an example of a semiconductor device configured by a top gate structure-bottom contact method.

As shown in FIG. 8, a semiconductor element 800 formed over a substrate 810 includes a semiconductor layer 805, a source electrode 820 and a drain electrode 822, a gate insulating layer 830, and a gate electrode 824.

In this example, the gate electrode 824 is disposed on the semiconductor layer 805 (top gate structure). On the other hand, the source electrode 820 and the drain electrode 822 are disposed below the semiconductor layer 805 (bottom contact method).

Next, FIG. 9 shows an example of a semiconductor device configured by a bottom gate structure-top contact method.

As shown in FIG. 9, a semiconductor element 900 formed over a substrate 910 includes a semiconductor layer 905, a source electrode 920 and a drain electrode 922, a gate insulating layer 930, and a gate electrode 924.

In this example, the gate electrode 924 is disposed below the semiconductor layer 905 (bottom gate structure). On the other hand, the source electrode 920 and the drain electrode 922 are disposed above the semiconductor layer 905 (top contact method).

Next, FIG. 10 shows an example of a semiconductor device configured by a bottom gate structure-bottom contact method.

As shown in FIG. 10, the semiconductor element 1000 formed over the substrate 1010 includes a semiconductor layer 1005, a source electrode 1020 and a drain electrode 1022, a gate insulating layer 1030, and a gate electrode 1024.

In this example, the gate electrode 1024 is disposed below the semiconductor layer 1005 (bottom gate structure). On the other hand, the source electrode 1020 and the drain electrode 1022 are also disposed below the semiconductor layer 1005 (bottom contact method).

The semiconductor element may be a channel etch type or a channel protection type.

As described above, there are various modes in the arrangement structure of the semiconductor elements. The semiconductor element in the organic electroluminescence device of the present invention may be arranged in any of these modes.

FIG. 11 schematically shows a cross section of an organic electroluminescence device (second organic electroluminescence device) according to another embodiment of the present invention.

As shown in FIG. 11, the second organic electroluminescence device 1101 basically has the same configuration as the first organic electroluminescence device 1 shown in FIG. Therefore, in FIG. 11, the same reference numerals used in FIG. 1 plus 1100 are used for the same members as in FIG.

However, in the second organic electroluminescence device 1101, the configuration of the semiconductor element 1200 is greatly different from that of the first organic electroluminescence device 1. That is, in the second organic electroluminescence device 1101, the semiconductor element 1200, that is, the first and second thin film transistors 1201 and 1202 are configured by a so-called bottom gate structure-top contact method.

Also in the second organic electroluminescence device 1101 having the semiconductor element 1200 having such a configuration, any one of the organic electroluminescence elements 1300 includes a thin film of an amorphous solid material containing calcium, aluminum, and oxygen. It will be apparent that the same effects as those of the first organic electroluminescence device 1 can be obtained.

Next, an organic electroluminescence device (third organic electroluminescence device, fourth organic electroluminescence device) according to another embodiment of the present invention will be described.

The third organic electroluminescence device includes a semiconductor element formed using a semiconductor substrate. A known structure formed using a semiconductor substrate can be used as the semiconductor element. For example, a part of the semiconductor substrate may be used as the semiconductor region. Other structures (source electrode, drain electrode, gate electrode, etc.) may be known structures. As the semiconductor substrate, for example, a silicon substrate, a germanium substrate, or the like may be used. Preferably, a single crystal semiconductor substrate (a single crystal silicon substrate or a single crystal germanium substrate) may be used. The gate insulating layer is not particularly limited, but a thermal oxide film is preferably used.

The fourth organic electroluminescence device includes a semiconductor element formed using an SOI (Silicon On Insulator) substrate. The SOI substrate has a structure in which an insulating layer (for example, SiO ₂ or the like) exists between a semiconductor substrate (for example, a silicon substrate) and a surface layer semiconductor layer (for example, a surface layer silicon layer). The surface semiconductor layer is preferably made of a single crystal semiconductor. An SOI substrate has a structure in which a crystalline semiconductor film (preferably a single crystal semiconductor film) is provided directly or indirectly on a substrate different from a semiconductor substrate such as a glass substrate, a plastic substrate, a resin substrate, or a ceramic substrate. May be. In this case, the crystalline semiconductor film corresponds to the surface semiconductor layer.

As the semiconductor element, a known configuration formed using an SOI substrate can be used. For example, a semiconductor layer may be formed using a surface semiconductor layer. Other structures (source electrode, drain electrode, gate electrode, etc.) may be known structures. The gate insulating layer is not particularly limited, but a thermal oxide film can be used.

In the third and fourth organic electroluminescence devices, the organic electroluminescence element 200 may be used as the organic electroluminescence element.

The third organic electroluminescence device preferably has a configuration in which light is extracted from the surface opposite to the semiconductor substrate. That is, it is preferable to use the organic electroluminescence element 200 having the light extraction surface on the side opposite to the semiconductor substrate.

In the third organic electroluminescence device, the semiconductor substrate may be thin so that light can be transmitted. The thinned semiconductor substrate may be bonded to a transparent substrate. By using the third organic electroluminescence device having a configuration in which the semiconductor substrate can transmit light as a glasses-type display such as a head-mounted display, the image on the display is visually confirmed and the glasses are passed through. You can see the outside.

Further, in the fourth organic electroluminescence device, when the SOI substrate has a configuration in which an insulating layer exists between the semiconductor substrate and the surface semiconductor layer, the same configuration as that of the third organic electroluminescence device (opposite to the semiconductor substrate). A structure in which light is extracted from the side surface, and a structure in which light can be transmitted by making the semiconductor substrate thin.

Further, the semiconductor elements included in the third and fourth organic electroluminescence devices have a top gate structure.

Also in the third and fourth organic electroluminescence devices, as long as any of the organic electroluminescence elements includes a thin film of an amorphous solid material containing calcium, aluminum, and oxygen, the first organic electroluminescence device 1 is used. It will be clear that the same effect can be obtained.

The organic electroluminescence device of the present invention is used as an image display device, for example, a mobile phone display, a personal digital assistant (PDA), a computer display, an automobile information display, a TV monitor, a digital camera viewfinder, a head mounted display ( HMD) and the like. The organic electroluminescence device of the present invention is used as various light emitting light sources, such as lighting devices (home lighting, interior lighting), clocks and backlights for liquid crystals, billboard advertisements, traffic lights, light sources for optical storage media, electronic It is used as a light source for photocopiers, a light source for optical communication processors, a light source for optical sensors, and the like.

In the present invention, each patterned electrode may be formed with a light emitting layer that is patterned so as to correspond to the emission wavelengths of red (R), green (G), and blue (B). Thereby, a display panel capable of full color display is realized. As a formula other than such a display method, a dye conversion method using a blue light emitting layer and a dye conversion layer may be used. Moreover, you may employ | adopt the structure in which the color filter was provided corresponding to each of the some organic electroluminescent element which light-emits white.

The present invention can be applied to an organic electroluminescence element or the like.

This application claims priority based on Japanese Patent Application No. 2013-077415 filed on April 3, 2013 and Japanese Patent Application No. 2013-138987 filed on July 2, 2013. The entire contents of the same Japanese application are incorporated herein by reference.

DESCRIPTION OF SYMBOLS 1 1st organic electroluminescent apparatus 10 1st passivation layer 20 2nd passivation layer 100 Semiconductor element 101 1st thin-film transistor 102 2nd thin-film transistor 105 Semiconductor layer 110 Substrate 120 Source electrode 122 Drain electrode 124 Gate electrode 200 Organic

electro Luminescent element

200A, 200B Organic electroluminescent element 210 Lower electrode 210a Anode 210b Cathode 220

Organic layer

220a, 220b

Organic layer

223a, 223b

Hole injection layer

224a, 224b

Hole transport layer

225a, 225b

Light emitting layer

226a, 226b

Electron transport layer

227a, 227b Electron injection layer 230 Upper electrode 230a Cathode 230b Anode 320 Gate wiring 322 Data wiring 24 drive wiring 326 capacitor 520 solvent (amorphous C12A7)
530 Cage 540 Electron (solute)
550

Bipolaron

700, 800, 900, 1000

Semiconductor element

705, 805, 905, 1005

Semiconductor layer

710, 810, 910, 1010

Substrate

720, 820, 920, 1020

Source electrode

722, 822, 922, 1022 Drain electrode 724, 824 , 924, 1024

Gate electrode

730, 830, 930, 1030 Gate insulating layer 1101 Second organic electroluminescence device 1110 First passivation layer 1120 Second passivation layer 1200 Semiconductor element 1201 First thin film transistor 1202 Second thin film transistor 1205 Semiconductor layer 1210 Substrate 1220 Source electrode 1222 Drain electrode 1224 Gate electrode 1300 Organic electroluminescence element 1310 Lower electrode 1320 Organic layer 1330 Upper electrode

Claims

A semiconductor element;
An organic electroluminescence element;
Have
The organic electroluminescence device includes a thin film of an amorphous solid material containing calcium, aluminum, and oxygen.
The organic electroluminescence element has an anode, an organic layer, and a cathode,
The organic electroluminescence device according to claim 1, wherein the thin film of the amorphous solid material is included in the organic layer or the cathode.
3. The organic electroluminescence device according to claim 1, wherein the thin film of the amorphous solid material is composed of amorphous C12A7 electride.
4. The organic electroluminescence device according to claim 1, wherein the semiconductor element includes a thin film transistor having a semiconductor layer.
The organic electroluminescent device according to claim 4, wherein the semiconductor layer includes amorphous silicon, polysilicon, single crystal silicon, an oxide semiconductor, or an organic semiconductor.
6. The organic electroluminescence device according to claim 5, wherein the oxide semiconductor contains In, Ga, and Zn.
The organic electroluminescence device according to claim 1, wherein the semiconductor element includes a part of a substrate having a function as a semiconductor as a semiconductor region.