JP2009302071A - Organic el element, and substrate used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic El element using an electrode layer containing a specific inorganic compound, excelling in transparency and durability, low in drive voltage, and high in emission luminance. <P>SOLUTION: In the organic electroluminescent element 100 with a positive electrode layer 10, an organic light-emitting layer 14 and a negative electrode layer 16 sequentially laminated therein, at least either of the positive electrode layer 10 and the negative electrode layer 16 contains at least one inorganic compound selected from group A-1, and at least one compound selected from the following group B-1. In this case, the group A-1 comprises chalcogenides, oxynitrides or nitrides of Si, Ge, Sn, Pb, Ga, In, Zn, Cd, Mg; and the group B-1 comprises chalcogenides, oxynitrides or nitrides of lanthanoid-based elements. By including the positive electrode layer 10 and the like each formed of such a specific organic compound, the organic EL element excelling transparency and durability, and providing high emission luminance even if a drive voltage is low can be provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an organic electroluminescence element (hereinafter sometimes referred to as an organic EL element), a substrate used for the organic EL element, and a manufacturing method thereof. More specifically, the present invention relates to an organic EL element suitable for use in a consumer or industrial display device (display) or a light source of a printer head, a substrate used in the organic EL element, and a method for manufacturing the same.

  2. Description of the Related Art Conventionally, organic EL elements having a structure in which an organic light emitting layer is sandwiched between electrodes have been intensively studied for the following reasons, and are the targets of development.

(1) Since it is a completely solid element, it is easy to handle and manufacture.

(2) Since self-emission is possible, a light emitting member is not required.

(3) Since it is excellent in visibility, it is suitable for a display.

(4) Full color is easy.

  However, the organic light emitting layer is an organic substance, and generally has a problem that it easily deteriorates because it is difficult to transport electrons and holes, and a leak current is likely to occur due to a change with time when used for a long time.

  Various devices have been conventionally devised for such problems.

For example, Patent Document 1 described later discloses an organic EL element that reduces the energy difference between the work function of the anode and the ionization energy of the hole transport layer, thereby extending the lifetime. In order to achieve such an object, Patent Document 1 describes that an anode uses a conductive metal oxide material having a work function larger than that of indium tin oxide (ITO). ing. As such conductive metal oxides, for example, RuOx, MoO ₃ , V ₂ O ₅ are described, and an organic EL element using these metal oxides is disclosed in Patent Document 1.

  In Patent Document 1, in order to improve the light transmittance (%), an anode having a two-layer structure in which a thin film made of these conductive metal oxide materials and ITO are laminated is proposed.

  Patent Document 2 below discloses an organic EL element including an insulating thin film layer between an electrode and an organic light emitting layer so as to enable long-term use. Specifically, the organic EL element disclosed in Patent Document 2 has an insulating property made of aluminum nitride, tantalum nitride, or the like between the anode layer and the organic light emitting layer or between the cathode layer and the organic light emitting layer. A configuration having a thin film layer is employed.

In addition, in Patent Document 3 below, NiO is provided between the electrode and the organic light emitting layer for the purpose of providing a low-cost organic EL device that does not use m-MTDATA or a tetraaryldiamine derivative. An inorganic material layer to which at least one of In ₂ O ₃ , ZnO, SnO ₂ or B, P, C, N, O is added, or an inorganic material made of Ni _1-x O (0.05 ≦ x ≦ 0.5) An organic EL element in which a material layer is formed is disclosed.

Japanese Patent No. 2824411 (Japanese Patent Laid-Open No. 9-63771) JP-A-8-288069 JP-A-9-260063

However, the organic EL device disclosed in Patent Document 1 still has insufficient hole mobility and durability even when a metal oxide material such as RuOx, MoO ₃ , V ₂ O ₅ is used. it is conceivable that. Further, a metal oxide material such as RuOx, MoO ₃ , V ₂ O ₅ has a light absorption coefficient value of 27000 cm ⁻¹ or more, indicating a large value. This means that the degree of coloring is strong. Therefore, the anode layer made of these metal oxide materials has an extremely low value of light transmittance (%) in the visible light region, for example, about 1/9 to 1/5 that of ITO. Therefore, the organic EL element has problems such as low light emission efficiency and a small amount of light that can be extracted outside. Moreover, even if a two-layered anode in which a thin film made of these metal oxide materials and ITO are laminated, the light transmittance (%) is about 1/2 of that of ITO, and the value is still low. The existence of a problem that the value is not practically used was confirmed. Further, when the anode layer having the two-layer structure is formed, the thickness of the ITO or metal oxide thin film must be limited to a value within a predetermined range, and there is a problem that manufacturing restrictions are large.

  Further, in the organic EL element disclosed in Patent Document 2, since the insulating thin film layer uses aluminum nitride, tantalum nitride, or the like, voltage loss (voltage drop) occurs in this portion (insulating thin film layer). As a result, there was a problem that the drive voltage tends to be high.

  Therefore, the inventors of the present application have studied the above problems earnestly, and by using a specific inorganic compound in combination with the electrode layer of the organic EL element, it is excellent in transparency and durability, and has a low voltage (for example, It has been found that even when a driving voltage of DC 10 V or less is applied, excellent light emission luminance can be obtained.

  That is, an object of the present invention is to provide an organic EL device having excellent transparency and durability, low driving voltage, and high emission luminance by providing an electrode layer containing a specific inorganic compound. To do. Furthermore, an object of this invention is to provide the manufacturing method of the organic EL element which can manufacture such an organic EL element efficiently.

  In order to solve the above problems, the present invention employs the following means.

  First, the organic EL device substrate of the present invention is an organic electroluminescence device substrate comprising at least an electrode layer and a base material, and the electrode layer is at least one compound selected from the following group A-1; It is an organic electroluminescent element substrate containing at least one compound selected from Group B-1.

  Here, the A-1 group is a chalcogenide, oxynitride, or nitride of Si, Ge, Sn, Pb, Ga, In, Zn, Cd, Mg, and the B-1 group is It is a chalcogenide, oxynitride or nitride of a lanthanoid element.

  Another configuration of the organic EL element substrate of the present invention is an organic electroluminescent element substrate comprising at least an electrode layer and a base material, and the electrode layer is at least one selected from the group A-2. A substrate for an organic electroluminescence device, comprising a compound and at least one compound selected from Group B-2.

  Here, the A-2 group is a chalcogenide, oxynitride, or nitride of Ge, Sn, Pb, Ga, In, Zn, Cd, Mg, and the B-2 group is a chalcogenide of a lanthanoid element. It is.

  The organic EL device substrate of the present invention is an organic electroluminescence device substrate, wherein the electrode layer is an anode layer.

  The substrate for an organic EL device of the present invention is a substrate for an organic electroluminescence device, wherein the electrode layer is a cathode layer.

According to the structures of these inventions, the compound of the A-1 group and the compound of the B-1 group are used in combination, or the compound of the A-2 group and the compound of the B-2 group are combined. By using it, the ionization potential of the electrode layer can be increased efficiently. Therefore, when an organic EL element is constructed using the organic EL element substrate of the present invention, an organic EL element having excellent durability, low driving voltage and high emission luminance can be obtained.

  In addition, the electrode layer configured as described above is characterized by excellent etching characteristics. Further, the electrode layer is formed by including Si chalcogenide or nitride thereof in the electrode layer in at least one of the groups A-1, A-2, B-1, or B-2. The adhesion between the substrate and the substrate can be further improved, and the electrode layer can be formed more uniformly. When the anode layer is composed of these inorganic compounds, it is preferable to set the ionization potential to a value of 5.6 eV or more in consideration of hole injectability. On the other hand, when the cathode layer is configured, it is preferable to set the ionization potential to a value less than 4.0 eV in consideration of electron injectability.

  The material shown in the present invention can have an ionization potential of 5.8 eV or more, and is extremely suitable as an anode material.

  The organic EL device substrate of the present invention is a substrate for an organic electroluminescence device, wherein the electrode layer has a specific resistance value of less than 1 Ω · cm.

  By adopting such means, it is possible to prevent a phenomenon in which light emission unevenness occurs in the display screen due to the high resistance of the electrode layer.

  Therefore, by limiting the specific resistance value of the electrode layer in this way, the injection property of electrons and holes can be improved, and the driving voltage of the organic EL element can be further lowered. Conversely, when the specific resistance value of the constituent material of the electrode layer exceeds 1 Ω · cm, it is preferable to have a two-layer structure with the electrode layer made of the constituent material having a specific resistance value of less than 1 Ω · cm.

  The organic EL device substrate of the present invention is a substrate for an organic electroluminescence device in which the compound of the A-1 group or the A-2 group is any one of Sn, In and Zn chalcogenides or nitrides. These compounds can constitute an organic EL device having particularly low quenching property and high emission luminance among the compounds of Group A-1 or Group A-2.

  Further, the organic EL device substrate of the present invention is for an organic electroluminescence device in which the compound of the B-1 group or the B-2 group is any one of oxides of Ce, Nd, Sm, Eu, Tb, and Ho. It is a substrate. By using these compounds in combination, the ionization potential and the band gap energy in the electrode layer can be easily adjusted.

  In the organic EL device substrate of the present invention, the total amount of the electrode layer is 100 at. %, The content of the compound of the B-1 group or B-2 group is 0.5 to 30 at. % Is a substrate for an organic electroluminescence element having a value in the range of%. By setting the value within such a range, it is possible to more easily adjust the value of the ionization potential in the electrode layer while maintaining high transparency (light transmittance). In addition, the electrode layer configured as described above is characterized by excellent etching characteristics with acid or the like.

  Moreover, the organic EL element substrate of the present invention is an organic electroluminescence element substrate in which the film thickness of the electrode layer is set to a value within the range of 1 to 100 nm. By comprising in this way, the organic EL element which is excellent in durability, has a low drive voltage, and high light emission luminance can be manufactured. Moreover, if the thickness of the electrode layer is in such a range, the thickness of the organic EL element will not be excessively increased.

  Next, the structure of this invention concerning an organic EL element is demonstrated.

  First, the organic EL device of the present invention is an organic electroluminescent device having a structure in which at least an anode layer, an organic light emitting layer, and a cathode layer are sequentially laminated, and the anode layer and the cathode layer, or any one of them. The electrode layer is an organic electroluminescence device comprising at least one compound selected from the following group A-1 and at least one compound selected from the following group B-1.

  Here, the A-1 group is a chalcogenide, oxynitride, or nitride of Si, Ge, Sn, Pb, Ga, In, Zn, Cd, Mg, and the B-1 group is a lanthanoid element. Of chalcogenides, oxynitrides, or nitrides.

  Another organic EL device of the present invention is an organic electroluminescence device having a structure in which at least an anode layer, an organic light emitting layer, and a cathode layer are sequentially laminated, and the anode layer and the cathode layer, or any one of them. One electrode layer is an organic electroluminescence device comprising at least one inorganic compound selected from the following group A-2 and at least one compound selected from the following group B-2.

  Here, the A-2 group is a chalcogenide, oxynitride, or nitride of Ge, Sn, Pb, Ga, In, Zn, Cd, Mg, and the B-2 group is a chalcogenide of a lanthanoid element. It is.

  Thus, by using the combination of the compound of the A-1 group and the compound of the B-1 group, or by combining the compound of the A-2 group and the compound of the B-2 group, The ionization potential of the layer can be increased efficiently. Therefore, it is possible to obtain an organic EL element that has excellent durability, low driving voltage, and high light emission luminance. In addition, the electrode layer configured as described above is characterized by excellent etching characteristics. Further, the electrode layer is formed by including Si chalcogenide or nitride thereof in the electrode layer in at least one of the groups A-1, A-2, B-1, or B-2. The adhesion between the substrate and the substrate can be further improved, and the electrode layer can be formed more uniformly.

  When the anode layer is composed of these compounds, the ionization potential is preferably set to a value of 5.6 eV or more in consideration of hole injectability. On the other hand, when the cathode layer is configured, it is preferable to set the ionization potential to a value less than 4.0 eV in consideration of electron injectability. The material shown in the present invention can have an ionization potential of 5.8 eV or more, and is extremely suitable as an anode material.

  The organic EL device of the present invention is an organic electroluminescence device having a specific resistance value of the anode layer and / or cathode layer, or any one of the electrode layers of less than 1 Ω · cm. With such a configuration, it is possible to prevent the occurrence of uneven light emission in the display screen due to the high resistance of the electrode layer.

  Therefore, by limiting the specific resistance value of the electrode layer in this way, the injection property of electrons and holes can be improved. Furthermore, the drive voltage of the organic EL element can be made lower. Conversely, when the specific resistance value of the constituent material of the electrode layer exceeds 1 Ω · cm, it is preferable to have a two-layer structure with the electrode layer made of the constituent material having a specific resistance value of less than 1 Ω · cm.

  Moreover, this invention is an organic electroluminescent element whose compound of the said A-1 group or A-2 group is either a chalcogenide or nitride of Sn, In, and Zn. Since these compounds have particularly low quenching properties among the compounds of Group A-1 or Group A-2, an organic electroluminescence device with higher emission luminance can be realized.

  Moreover, this invention is an organic electroluminescent element whose compound of the said B-1 group or B-2 group is an oxide of the substance in any one of Ce, Nd, Sm, Eu, Tb, and Ho. By using these compounds in combination, the ionization potential and the band gap energy in the electrode layer can be easily adjusted.

  In the present invention, the total amount of the electrode layer is 100 at. %, The content of the compound of the B-1 group or B-2 group is 0.5 to 30 at. It is an organic electroluminescent element which becomes a value within the range of%. By setting the value within such a range, the ionization potential value in the electrode layer can be more easily adjusted while maintaining high transparency (light transmittance). In addition, the electrode layer configured as described above is characterized by excellent etching characteristics with acid or the like.

  Moreover, this invention is an organic electroluminescent element which makes the film thickness of the said electrode layer the value within the range of 1-100 nm. By comprising in this way, while being excellent in durability, an organic EL element with a low drive voltage and high light emission luminance can be obtained. Moreover, if the thickness of the electrode layer is in such a range, the thickness of the organic EL element will not be excessively increased.

  In addition, the present invention provides at least one selected from the group A-1 between the anode layer and the organic light emitting layer and / or between the cathode layer and the organic light emitting layer. An inorganic thin film layer containing an inorganic compound and at least one compound selected from Group B-1, or at least one compound selected from Group A-2 and at least one compound selected from Group B-2 It is an organic electroluminescent element which provides the inorganic thin film layer containing this.

  By further providing the inorganic thin film layer as described above, the leakage current can be efficiently suppressed, the efficiency of the organic EL element can be increased, and the durability is improved.

  In addition, when providing an inorganic thin film layer between an anode layer and an organic light emitting layer, it is very preferable to make a composition of an anode layer and an inorganic thin film layer different. Specifically, the A-1 group compound / B-1 group compound = 70 to 90 at. % / 0.5-10 at. % Compound, the inorganic thin film layer has an A-1 group compound / B-1 group compound = 50 to 90 at. % / 10 at. % Over 50 at. It is preferable to use a compound consisting of%. The same applies to the case of using compounds of groups A-2 and B-2.

  Further, according to the present invention, the organic light emitting layer includes an organic compound containing at least one aromatic compound having a styryl group represented by any one of the following general formulas (chemical formula 1) to (chemical formula 3). It is an electroluminescence element.

ここで、一般式（化学式１）中、Ａｒ^１は、炭素数が６〜４０の芳香族基であり、Ａｒ^２、Ａｒ^３、及びＡｒ^４は、それぞれ水素原子又は炭素数が６〜４０の芳香族基であり、Ａｒ^１、Ａｒ^２、Ａｒ^３、及びＡｒ^４の少なくとも一つは芳香族基であり、縮合数ｎは、１〜６の整数である。

Here, in the general formula (Chemical Formula 1), Ar ¹ is an aromatic group having 6 to 40 carbon atoms, and Ar ² , Ar ³ , and Ar ⁴ are each a hydrogen atom or 6 to 40 carbon atoms. It is an aromatic group, and at least one of Ar ¹ , Ar ² , Ar ³ , and Ar ⁴ is an aromatic group, and the condensation number n is an integer of 1-6.

ここで、一般式（化学式２）中、Ａｒ^５は、炭素数が６〜４０の芳香族基であり、Ａｒ^６及びＡｒ^７は、それぞれ水素原子又は炭素数が６〜４０の芳香族基であり、Ａｒ^５、Ａｒ^６及びＡｒ^７の少なくとも一つはスチリル基で置換されており、縮合数ｍは、１〜６の整数である。

Here, in the general formula (Chemical Formula 2), Ar ⁵ is an aromatic group having 6 to 40 carbon atoms, and Ar ⁶ and Ar ⁷ are each a hydrogen atom or an aromatic group having 6 to 40 carbon atoms. Yes, at least one of Ar ⁵ , Ar ⁶ and Ar ⁷ is substituted with a styryl group, and the condensation number m is an integer of 1 to 6.

ここで、一般式（化学式３）中、Ａｒ^８及びＡｒ^１４は、炭素数が６〜４０の芳香族基であり、Ａｒ^９〜ｒ^１３は、それぞれ水素原子又は炭素数が６〜４０の芳香族基であり、Ａｒ^８〜Ａｒ^１４の少なくとも一つはスチリル基で置換されており、縮合数ｐ、ｑ、ｒ、ｓは、それぞれ０又は１である。

Here, in the general formula (Chemical Formula 3), Ar ⁸ and Ar ¹⁴ are aromatic groups having 6 to 40 carbon atoms, and Ar ^{9 to} r ¹³ are each a hydrogen atom or an aromatic group having 6 to 40 carbon atoms. And at least one of Ar ^{8 to} Ar ¹⁴ is substituted with a styryl group, and the condensation numbers p, q, r, and s are each 0 or 1.

  According to another aspect of the present invention, there is provided an organic electroluminescence element manufacturing method, wherein the electrode layer is formed by a sputtering method, and the organic light emitting layer is formed by a vacuum evaporation method. It is a manufacturing method. When formed in this manner, a hole injection layer and an organic light emitting layer having a dense and uniform film thickness can be formed. Accordingly, it is possible to provide an organic EL element having more uniform light emission luminance.

  As described above in detail, according to the organic electroluminescence device of the present invention, by providing an anode layer or the like made of a specific organic compound, it has excellent transparency and durability, and high light emission even with a low driving voltage. An organic EL device capable of obtaining luminance can be provided. It was also confirmed that an anode layer made of a specific inorganic compound has excellent etching characteristics.

  Moreover, according to the organic electroluminescent element board | substrate of this invention, the organic electroluminescent element which shows such a favorable performance can be manufactured easily.

  Further, according to the method for producing an organic EL element of the present invention, it is possible to efficiently provide an organic EL element that is excellent in transparency and durability as described above and can obtain high emission luminance even when the driving voltage is low. Became.

It is sectional drawing of the organic EL element in 1st Embodiment. It is sectional drawing of the organic EL element in 2nd Embodiment. It is sectional drawing of the organic EL element in 3rd Embodiment. It is sectional drawing of the organic EL element in 4th Embodiment. It is a perspective view of the vacuum evaporation system in 5th Embodiment. It is sectional drawing of the vacuum evaporation system in 5th Embodiment. It is a figure where it uses for description of the measurement point in a board | substrate. It is a figure of chemical structural formula showing each chemical substance.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The drawings to be referred to schematically show the size, shape, and arrangement relationship of each component to the extent that the present invention can be understood, and the ratio of each part differs from an actual element or the like. Therefore, the present invention is not limited to the illustrated example. In the drawings, hatching indicating a cross section may be omitted.

[First Embodiment]
First, with reference to FIG. 1, 1st Embodiment in the organic EL element of this invention is described. FIG. 1 is a cross-sectional view of the organic EL element 100. As shown in this figure, the organic EL element 100 has a structure in which an anode layer 10, an organic light emitting layer 14, and a cathode layer 16 are sequentially laminated on a substrate (not shown).

  Hereinafter, the anode layer 10 and the organic light emitting layer 14 which are characteristic parts in the first embodiment will be mainly described. The other components, for example, the configuration and manufacturing method of the cathode layer 16 and the like will be described very simply, and the portions not mentioned are various configurations generally known in the field of organic EL elements. The manufacturing method can be taken.

  In the first embodiment, the anode layer 10 is composed of an A-1 group or an A-2 group (hereinafter collectively referred to as an A group) and a B-1 group or a B-2 group (hereinafter referred to as “group A”). , Which are collectively referred to as Group B). However, the cathode layer 16 may be made of the inorganic compound after setting the work function of the inorganic compound to a value less than 4.0 eV.

(1) Constituent material of anode layer 10 The anode layer 10 of the first embodiment includes a combination of the following A-1 group inorganic compounds and B-1 group compounds, or the following A-2. One of the constitutions containing a combination of the inorganic compounds of the group and the compounds of the group B-2 is employed. However, the combination of the inorganic compound of the A-1 group and the compound of the B-1 group and the combination of the inorganic compound of the A-2 group and the compound of the B-2 group are partially overlapped. There are compounds.

Group A-1: Si, Ge, Sn, Pb, Ga, In, Zn, Cd, Mg chalcogenide, oxynitride, or nitride A-2 group: Ge, Sn, Pb, Ga, In, Zn, Cd , Mg chalcogenides, oxynitrides, or nitrides B-1 group: chalcogenides, oxynitrides, or nitrides of lanthanoid elements B-2 groups: chalcogenides of lanthanoid elements The reason for combining the two compounds is that, as described above, it is difficult to efficiently increase the value of the ionization potential with only one of the compounds (group A or group B) (organic compound or inorganic compound). Because. Specifically, it is difficult to raise the ionization potential to a value exceeding 5.8 eV.

  Therefore, by combining the inorganic compound of Group A-1 and the compound of Group B-1 or combining the inorganic compound of Group A-2 and the compound of Group B-2 to constitute the anode layer 10, the ionization potential is increased. It can be set to an extremely large value of 5.8 eV or more. As a result, it is possible to obtain an organic EL element that is excellent in durability and transparency, has a low driving voltage (low specific resistance), and high emission luminance.

  Moreover, the compound which combined the inorganic compound of the A-1 group and the compound of the B-1 group, or the compound which combined the inorganic compound of the A-2 group and the compound of the B-2 group is an acid such as hydrochloric acid or oxalic acid. It has the feature that the etching characteristic by is excellent. Specifically, the cross section at the boundary between the acid treatment part and the non-treatment part is smooth, and the areas of the acid treatment part and the non-treatment part can be clearly distinguished. Therefore, an electrode layer composed of such an inorganic compound has excellent etching accuracy of an electrode pattern, and even if it is a microelectrode or an electrode having a complicated shape, disconnection, deformation, increase in resistance value, etc. are reduced. An effect is obtained.

Group A inorganic compounds As the more specific A-1 Group inorganic compound, SiOx (1 ≦ x ≦ 2 ), GeOx (1 ≦ x ≦ 2), SnO 2, PbO, In 2 O 3, ZnO, GaO, CdO, ZnS, ZnCe, CdSe, Inx ZnyO (0.2≤x / (x + y) ≤0.95), ZnOS, CdZnO, CdZnS, MgInO, CdInO, MgZnO, GaN, InGaN, MgZnSSe, etc. .

  Specific examples of the inorganic compound of Group A-2 include compounds obtained by removing SiOx (1.ltoreq.x.ltoreq.2) from the inorganic compound of Group A-1. Here, of course, ZnO is an oxide of Zn, and ZnS means a sulfide of Zn. In particular, in this embodiment, Zn and O, and Zn and S have a ratio of 1: 1, respectively. In addition to the regular composition, it also includes a proportion of compounds that deviate from it.

  In the inorganic compounds of the A-1 group and the A-2 group, Sn, In, and Zn chalcogenides or nitrides thereof are particularly preferable materials. The reason for this is that, as described above in part, these compounds have a small absorption coefficient among the inorganic compounds of the A-1 group and the A-2 group, particularly low quenching properties and excellent transparency. This is because the amount of light that can be taken out can be increased. Moreover, in the chalcogenide of Ge, Sn, Zn, and Cd described above, these oxides are more preferable.

Group B compounds As specific Group B-1 compounds, Ce ₂ O ₃ , CeO ₂ , Pr ₆ O ₁₁ , Nd ₂ O ₃ , Sm ₂ O ₃ , Eu ₂ O ₃ , Gd ₂ O ₃ , Tb ₄ O ₇ , Dy ₂ O ₃ , Ho ₂ O ₃ , Er ₂ O ₃ , Tm ₂ O ₃ , Yb ₂ O ₃ , Lu ₂ O ₃ , CeN, PrN, NdN, SmN, EuN, GdN, TbN, DyN , HoN, ErN, TmN, YbN, LuN, etc., or a combination of two or more.

Specific compounds of Group B-2 include Ce ₂ O ₃ , CeO ₂ , Pr ₆ O ₁₁ , Nd ₂ O ₃ , Sm ₂ O ₃ , Eu ₂ O ₃ , Gd ₂ O ₃ , and Tb ₄ O. ₇ , Dy ₂ O ₃ , Ho ₂ O ₃ , Er ₂ O ₃ , Tm ₂ O ₃ , Yb ₂ O ₃ , Lu ₂ O _3, or a single type or a combination of two or more types.

Of these B-1 group and B-2 group of compounds, Ce, Nd, Sm, Eu , oxides of Tb and Ho, _{i.e., CeOx, Nd 2 O 3,} Sm 2 O 3, Eu 2 O 3, Tb ₄ O _7, and more preferably Ho ₂ O _3. This is also because, as described above in part, by using these inorganic compounds, the value of the ionization potential in the anode layer 10 can be increased more efficiently.

Group B (Group B-1 or Group B-2) Compound Content Next, the content of the compound of Group B (the Group B-1 or Group B-2 is simply referred to as Group B) will be described. The content of the compound of Group B is set to 100 at. %, 0.5 to 30 at. It is preferable to set the value within the range of%. This is because the content of the compound of Group B is 0.5 at. This is because the adjustment property of the ionization potential of the anode layer 10 is deteriorated when it is less than%. Specifically, it may be difficult to adjust the ionization potential within the range of 5.65 to 6.40 eV. On the other hand, the content of the compound of Group B is 30 at. This is because if the content exceeds 50%, the conductivity may be reduced, coloring may occur, or transparency (light transmittance) may be reduced.

  Therefore, since the balance between the adjustment of the ionization potential value in the anode layer 10 and the transparency becomes better, the content of the group B compound is set to 100 at. %, 0.8-20 at. %, More preferably 1 to 10 at. More preferably, the value is within the range of%.

Group A (Group A-1 or Group A-2) Compound Content Note that the content of the inorganic compound in Group A (Group A-1 or Group A-2 is simply referred to as Group A) is the anode layer 10. Is composed of the compounds of Group A (Group A-1 or Group A-2) and Group B (Group B-1 or Group B-2), the total amount is 100 at. The value obtained by subtracting the content of the compound of Group B from%. Therefore, the content of the compound of Group B is 0.5 to 30 at. %, The content of the group A inorganic compound in the anode layer 10 is 70 to 99.5 at. The value is in the range of%.

  However, when the anode layer 10 contains a compound (third component) other than the A group and the B group, the content of the inorganic compound of the A group should be determined in consideration of the content of the third component. Is preferred.

The thickness and structure of the anode layer and the thickness of the anode layer 10 are not particularly limited, but specifically, it is preferably set to a value in the range of 0.5 to 1000 nm. The reason for this is that when the thickness of the anode layer 10 is less than 0.5 nm, pinholes may occur when used for a long period of time, and a leakage current may be observed. This is because if the film thickness exceeds 1000 nm, the transparency of the electrode is lowered and the light emission luminance may be lowered. Therefore, since the balance between the durability and the value of the driving voltage becomes better, it is more preferable to set the film thickness of the anode layer 10 to a value within the range of 1.0 to 800 nm. It is even more preferable to set the value within the range. Further, the structure of the anode layer 10 is not particularly limited, and may be a single layer structure or a multilayer structure of two or more layers. Therefore, when it is desired to obtain higher transparency (light transmittance) and higher conductivity, a conductive electrode layer having higher transparency or a conductive electrode layer having higher conductivity, such as ITO or In2O3-ZnO, is used. It can also be laminated to form a two-layer structure.

Specific Resistance of Anode Layer Next, the specific resistance of the anode layer 10 will be described. The value of the specific resistance is not particularly limited, but is preferably set to a value less than 1 Ω · cm, for example. This is because when the value of the specific resistance is 1 Ω · cm or more, non-uniformity of light emission in the pixel occurs, and the drive voltage of the organic EL element to be manufactured may increase. Therefore, in order to achieve a lower driving voltage, the specific resistance of the anode layer 10 is preferably set to a value of 40 mΩ · cm or less, and more preferably set to a value of 1 mΩ · cm or less. In addition, the value of the specific resistance of the anode layer 10 can be calculated by measuring the surface resistance using a four-probe method resistance measuring machine and measuring the film thickness separately.

The method of forming the anode layer Next, a method for forming the anode layer 10. Such a forming method is not particularly limited to a specific method. For example, a sputtering method, a vapor deposition method, a spin coating method, a sol-gel method using a casting method, a spray pyrolysis method, an ion plating method, or the like can be employed. In particular, it is preferable to employ a high-frequency magnetron sputtering method. Specifically, sputtering is preferably performed under the conditions of a degree of vacuum of 1 × 10 ⁻⁷ to 1 × 10 ⁻³ Pa, a film formation rate of 0.01 to 50 nm / second, and a substrate temperature of −50 to 300 ° C.

(2) Organic Light-Emitting Layer Next, the organic light-emitting layer will be described.

Organic Light-Emitting Layer Constituent Material The organic light-emitting material used as the constituent material of the organic light-emitting layer 14 preferably has the following three functions.

(A) Charge injection function: A function capable of injecting holes from the anode or the hole injection layer and applying electrons from the cathode layer or the electron injection layer when an electric field is applied.

(B) Transport function: a function of moving injected holes and electrons by the force of an electric field.

(C) Light emitting function: A function that provides a field for recombination of electrons and holes and connects them to light emission.

  However, it is not always necessary to have all the above functions (a) to (c). For example, the organic light-emitting material is one in which the hole injecting and transporting property is larger than the electron injecting and transporting property. There are suitable ones. Therefore, any material can be preferably used as long as the movement of electrons in the organic light emitting layer 14 is promoted and holes and electrons can be recombined near the center inside the organic light emitting layer 14.

Here, in order to improve the recombination property in the organic light emitting layer 14, the electron mobility of the organic light emitting material is preferably set to a value of 1 × 10 ⁻⁷ cm ² / V · s or more. This is because, when the value is less than 1 × 10 ⁻⁷ cm ² / V · s, high-speed response in the organic EL element may be difficult or the light emission luminance may be reduced. Therefore, the electron mobility of the organic light emitting material is more preferably set to a value within a range of 1.1 × 10 ⁻⁷ to 2 × 10 ⁻³ cm ² / V · s, and 1.2 × 10 ⁻⁷ −. More preferably, the value is within the range of 7 to 1.0 × 10 ⁻³ cm ² / V · s.

  Moreover, it is preferable to make the value of electron mobility smaller than the hole mobility of the organic light emitting material in the organic light emitting layer 14. When this relationship is reversed, the organic light emitting material that can be used for the organic light emitting layer 14 may be excessively limited, and the light emission luminance may be reduced. On the other hand, it is preferable that the electron mobility of the organic light emitting material is larger than 1/1000 of the value of hole mobility. This is because if the electron mobility becomes excessively small, it becomes difficult for holes and electrons to recombine in the vicinity of the center inside the organic light emitting layer 14, and the light emission luminance may decrease. Therefore, it is more preferable that the hole mobility (μh) and the electron mobility (μe) of the organic light emitting material in the organic light emitting layer 14 satisfy the relationship of μh / 2> μe> μh / 500, and μh / 3. More preferably, the relationship of> μe> μh / 100 is satisfied.

  In the first embodiment, it is preferable to use an aromatic ring compound having a styryl group represented by the above general formulas (1) to (3) for the organic light emitting layer 14. By using such an aromatic ring compound having a styryl group, the above-described conditions for the electron mobility and hole mobility of the organic light emitting material in the organic light emitting layer 14 can be easily satisfied. Among the aromatic groups having 6 to 40 carbon atoms in the general formulas (1) to (3), preferred aryl groups having 5 to 40 carbon atoms include phenyl, naphthyl, anthranyl, phenanthryl, pyrenyl, coronyl, biphenyl, Examples include terphenyl, pyrrolyl, furanyl, thiophenyl, benzothiophenyl, oxadiazolyl, diphenylanthranyl, indolyl, carbazolyl, pyridyl, benzoquinolyl and the like.

  Preferred arylene groups having 5 to 40 nuclear atoms include phenylene, naphthylene, anthranylene, phenanthrylene, pyrenylene, colonylene, biphenylene, terphenylene, pyrrolylene, furanylene, thiophenylene, benzothiophenylene, oxadiazolylene, diphenylanthranylene. , Indolylene, carbazolylene, pyridylene, benzoquinolylene and the like. The aromatic group having 6 to 40 carbon atoms may be further substituted with a substituent. Preferred substituents include alkyl groups having 1 to 6 carbon atoms (ethyl group, methyl group, i-propyl group). N-propyl group, s-butyl group, t-butyl group, pentyl group, hexyl group, cyclopentyl group, cyclohexyl group, etc.), alkoxy group having 1 to 6 carbon atoms (ethoxy group, methoxy group, i-propoxy group, n-propoxy group, s-butoxy group, t-butoxy group, pentoxy group, hexyloxy group, cyclopentoxy group, cyclohexyloxy group, etc.), aryl group having 5 to 40 nuclear atoms, and having 5 to 40 nuclear atoms An amino group substituted with an aryl group, an ester group having an aryl group having 5 to 40 nucleus atoms, an ester group having an alkyl group having 1 to 6 carbon atoms, a cyano group, a nitro group, a halo It is down atom and the like.

  Moreover, it is also preferable to use together with the organic light emitting layer 14 a fluorescent whitening agent such as benzothiazole, benzimidazole, and benzoxazole, or a metal complex having a styrylbenzene compound or an 8-quinolinol derivative as a ligand. . Further, an organic light-emitting material having a distyrylarylene skeleton, such as 4,4′-bis (2,2-diphenylvinyl) biphenyl, is used as a host, and a strong fluorescent dye from blue to red, such as a coumarin-based or host, It is also suitable to use a material doped with the same fluorescent dye.

Method for Forming Organic Light-Emitting Layer Next, a method for forming the organic light-emitting layer 14 will be described. Such a forming method is not limited to a specific method. For example, methods such as a vacuum deposition method, a spin coating method, a casting method, an LB method, and a sputtering method can be employed. For example, in the case of forming by a vacuum deposition method, the deposition temperature is 50 to 450 ° C., the degree of vacuum is 1 × 10 ⁻⁷ to 1 × 10 ⁻³ Pa, the film formation rate is 0.01 to 50 nm / second, and the substrate temperature is −50 to 300. It is preferable to adopt the condition of ° C.

  Alternatively, the organic light emitting layer 14 can also be formed by dissolving the binder and the organic light emitting material in a predetermined solvent to form a solution and then reducing the film thickness by spin coating or the like. The organic light emitting layer 14 is formed by selecting a forming method and forming conditions as appropriate and solidifying from a thin film formed by deposition from a material compound in a gas phase state or a material compound in a solution state or a liquid phase state. It is preferable to use a molecular deposition film which is a thick film. Usually, this molecular deposited film can be sufficiently distinguished from a thin film (molecular accumulated film) formed by the LB method by the difference in aggregated structure and higher order structure and the functional difference resulting therefrom.

The film thickness of the organic light emitting layer The film thickness of the organic light emitting layer 14 is not particularly limited, and an appropriate film thickness can be selected according to the situation, but in reality, a value in the range of 5 nm to 5 μm is preferable. There are many cases. The reason for this is that when the thickness of the organic light emitting layer is less than 5 nm, the light emission luminance and durability may be reduced. This is because there are many cases. Therefore, since the balance with the value of light emission luminance, applied voltage, etc. becomes better, the thickness of the organic light emitting layer 14 is more preferably set to a value within the range of 10 nm to 3 μm, and within the range of 20 nm to 1 μm. More preferably, the value of

(3) Cathode layer It is preferable to use a metal, an alloy, an electrically conductive compound, or a mixture thereof having a small work function (for example, less than 4.0 eV) for the cathode layer 16. Specifically, magnesium, aluminum, indium, lithium, sodium, cesium, silver, or the like can be used alone or in combination of two or more. The thickness of the cathode layer 16 is not particularly limited, but is preferably a value in the range of 10 to 1000 nm, more preferably a value in the range of 10 to 200 nm.

(4) Others Although not shown in FIG. 1, it is also preferable to provide a sealing layer for preventing moisture and oxygen from entering the organic EL element 100 so as to cover the entire organic EL element 100. As a preferable material for the sealing layer, a copolymer obtained by copolymerizing a monomer mixture containing tetrafluoroethylene and at least one comonomer; a fluorinated copolymer having a cyclic structure in the copolymer main chain; Examples include polyethylene, polypropylene, polymethyl methacrylate, polyimide, polyurea, polytetrafluoroethylene, polychlorotrifluoroethylene, polydichlorodifluoroethylene, or a copolymer of chlorotrifluoroethylene and dichlorodifluoroethylene.

Further, preferable sealing layer materials include a water-absorbing substance having an absorption rate of 1% or more; a moisture-proof substance having a water absorption rate of 0.1% or less; In, Sn, Pb, Au, Cu, Ag, Al, Ti, Ni Metals such as MgO, SiO, SiO ₂ , GeO, NiO, CaO, BaO, Fe ₂ O, Y ₂ O ₃ , TiO _2, etc .; Metals such as MgF ₂ , LiF, AlF ₃ , and CaF ₂ Fluoride; liquid fluorinated carbon such as perfluoroalkane, perfluoroamine, and perfluoropolyether; and a composition in which an adsorbent that adsorbs moisture and oxygen is dispersed in the liquid fluorinated carbon.

  In forming the sealing layer, vacuum deposition, spin coating, sputtering, casting, MBE (molecular beam epitaxy), cluster ion beam deposition, ion plating, plasma polymerization (high frequency excitation) An ion plating method), a reactive sputtering method, a plasma CVD method, a laser CVD method, a thermal CVD method, a gas source CVD method, and the like can be appropriately employed.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a cross-sectional view of the organic EL element 102 according to the second embodiment. The anode layer 10, the inorganic thin film layer 12, the organic light emitting layer 14, and the cathode layer 16 are sequentially formed on a substrate (not shown). It represents having a laminated structure. By providing the inorganic thin film layer 12 in this way, injected holes can be efficiently transported. Therefore, by providing the inorganic thin film layer 12, the organic EL element 102 can be driven at a low voltage and the durability is improved.

  In addition, the characteristic matter in the organic EL element 102 of the second embodiment is that the inorganic thin film layer 12 is inserted between the anode layer 10 and the organic light emitting layer 14.

Except this point, it has the same structure as the organic EL element 100 of the first embodiment.

  Therefore, the following description mainly relates to the inorganic thin film layer 12 which is a characteristic part in the second embodiment, and other components such as the cathode layer 16 are the first embodiment. Refer to the description of the first embodiment because it has the same configuration as the first embodiment.

  First, as an inorganic compound which comprises the inorganic thin film layer 12, the A group (A-1 group or A-2 group) and B group (B-1 group or B-2 group) which comprise the anode layer 10 mentioned above are used. Combinations of compounds are mentioned. Therefore, in the same manner as the anode layer 10, the total amount of the inorganic thin film layer is set to 100 at. %, 0.5 to 50 at. % In the range of 1.0 to 40 at. % In the range of 5.0 to 30 at. More preferably, the value is within the range of%. Moreover, it is preferable to set it as the structure similar to the anode layer 10 also about the film thickness and the formation method.

  However, when providing the inorganic thin film layer 12 between the anode layer 10 and the organic light emitting layer 14, it is necessary to make the composition of the anode layer 10 and the inorganic thin film layer 14 different. Specifically, the anode layer 10 has a group A (group A-1 or group A-2) / group B (group B-1 or group B-2) = 70 to 90 at. % / 0.5-10 at. %, While the inorganic thin film layer 12 has a group A (group A-1 or group A-2) / group B (group B-1 or group B-2) = 50 to 90 at. % / 10 at. % Over 50 at. It is preferable to use an inorganic compound consisting of%. This is because when the amount of the compound in Group B (Group B-1 or Group B-2) is out of this range, the transparency is lowered or the specific resistance is increased, which is not preferable as an electrode.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 3 is a cross-sectional view of the organic EL element 104 according to the third embodiment. The anode layer 10, the inorganic thin film layer 12, the hole transport layer 13, the organic light emitting layer 14, and the cathode layer 16 are disposed on a substrate (not shown). No.) shows that it has a layered structure.

  In the third embodiment, in addition to the first and second embodiments, the hole transport layer 13 is further provided, whereby the injected holes can be efficiently transported. Therefore, by providing the hole transport layer 13, the organic EL element 104 can be driven at a low voltage and the durability is improved.

  The organic EL element 104 of the third embodiment is the same as that of the second embodiment except that the hole transport layer 13 is inserted between the inorganic thin film layer 12 and the organic light emitting layer 14. This has the same structure as that of the organic EL element 102 of the embodiment. Therefore, the following description will be focused on the hole transport layer 13 which is a characteristic part in the third embodiment. Other components such as the cathode layer 16 can be configured in the same manner as in the first and second embodiments, so refer to the description of the first and second embodiments.

(1) Constituent material of the hole transport layer 13 The hole transport layer 13 is preferably composed of an organic compound or an inorganic compound. Examples of such organic materials include phthalocyanine compounds, diamine compounds, diamine-containing oligomers, and thiophene-containing oligomers. Examples of preferable inorganic compound materials include amorphous silicon (α-Si), α-SiC, microcrystal silicon (μC-Si), μC-SiC, II-VI group compounds, III-V group compounds, non- Examples thereof include crystalline carbon, crystalline carbon, and diamond. Other types of inorganic materials include oxides, fluorides, and nitrides. More specifically, Al ₂ O ₃ , SiO, SiOx (1 ≦ x ≦ 2), GaN, InN, GaInN, GeOx ( 1 ≦ x ≦ 2), LiF, SrO, CaO, BaO, MgF ₂ , CaF ₂ , UgF ₂ , SiNx (1 ≦ x ≦ 4/3) and the like alone or in combination of two or more. The hole mobility is 1 × 10 ⁶ cm ² / V · sec or more (applied voltage 1 × 10 ⁴ to 1 × 10 ⁶ V / cm), and the ionization potential is 5.5 eV or less. It is preferable to select the constituent materials so as to satisfy the following values.

(2) Structure and formation method of the hole transport layer 13 The hole transport layer 13 is not limited to a single layer structure, and may be, for example, a two layer structure or a three layer structure. Further, the thickness of the hole transport layer 13 is not particularly limited, but is preferably set to a value in the range of 0.5 nm to 5 μm, for example. Moreover, there is no restriction | limiting in particular also about the formation method of the positive hole transport layer 13, A various method is employable. However, practically, it is preferable to adopt a method similar to the method of forming the hole injection layer.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 4 is a cross-sectional view of the organic EL element 106 according to the fourth embodiment. The anode layer 10, the inorganic thin film layer 12, the hole transport layer 13, the organic light emitting layer 14, the electron injection layer 15, and the cathode layer 16 are It shows that it has the structure laminated | stacked sequentially on the board | substrate (not shown). As described above, in the fourth embodiment, the function of efficiently injecting electrons can be exhibited by providing the electron injection layer 15. Therefore, the provision of the electron injection layer 15 facilitates movement of electrons to the organic light emitting layer 14 and improves the response performance of the organic EL element 106.

  A characteristic point of the organic EL element 106 in the fourth embodiment is that an electron injection layer 15 is inserted between the organic light emitting layer 14 and the cathode layer 16. Except for this point, the organic EL element 106 of the fourth embodiment has the same structure as the organic EL element 104 of the third embodiment. Therefore, the following description will be focused on the electron injection layer 15 which is a characteristic part in the fourth embodiment, and the other components will be the same as those in the first to third embodiments described above. Or a configuration generally known in the field of organic EL elements can be employed.

(1) Constituent material of electron injection layer The electron injection layer 15 is preferably composed of an organic compound or an inorganic compound. In particular, an organic EL element that is superior in electron injectability and durability from the cathode can be obtained by being composed of an organic compound. Here, preferred organic compounds include 8-hydroxyquinoline, oxadiazole, or derivatives thereof such as metal chelate oxinoid compounds containing 8-hydroxyquinoline.

  Moreover, when the electron injection layer 15 is comprised with an inorganic compound, it is preferable to use an insulator or a semiconductor as this inorganic compound. If the electron injection layer 15 is made of an insulator or a semiconductor, current leakage can be effectively prevented and the electron injection property can be improved. Such insulators are selected from the group consisting of alkali metal chalcogenides (oxides, sulfides, selenides, tellurides), alkaline earth metal chalcogenides, alkali metal halides and alkaline earth metal halides. Preferably at least one metal compound is used. If the electron injection layer 15 is composed of these alkali metal chalcogenides or the like, it is preferable in that the electron injection property can be further improved.

Specifically, preferable alkali metal chalcogenides include, for example, Li ₂ O, LiO, Na ₂ S, Na ₂ Se, and NaO. Preferred alkaline earth metal chalcogenides include, for example, CaO, BaO, SrO, BeO, BaS, and CaSe. Further, preferable alkali metal halides include, for example, LiF, NaF, KF, LiCl, KCl, and NaCl. Examples of preferable alkaline earth metal halides include fluorides such as CaF ₂ , BaF ₂ , SrF ₂ , MgF ₂ and BeF ₂ , and halides other than fluorides.

  When the electron injection layer 15 is made of a semiconductor, preferable semiconductors include at least one of Ba, Ca, Sr, Yb, Al, Ga, In, Li, Na, Cd, Mg, Si, Ta, Sb, and Zn. One kind or a combination of two or more kinds of oxides, nitrides or oxynitrides containing two elements may be mentioned. The inorganic compound constituting the electron injection layer 15 is preferably a microcrystalline or amorphous insulating thin film. If the electron injection layer 15 is composed of these insulating thin films, a more uniform thin film is formed, so that pixel defects such as dark spots can be reduced. Examples of such inorganic compounds include the alkali metal chalcogenides, alkaline earth metal chalcogenides, alkali metal halides, and alkaline earth metal halides described above.

(2) Electron affinity The electron affinity of the electron injection layer 15 in the fourth embodiment is preferably set to a value in the range of 1.8 to 3.6 eV. If the electron affinity value is less than 1.8 eV, the electron injection property tends to decrease, leading to an increase in driving voltage and a decrease in light emission efficiency. On the other hand, if the electron affinity value exceeds 3.6 eV, light emission is likely to occur. It becomes easy to generate a complex with low efficiency, and generation | occurrence | production of blocking junction can be suppressed efficiently. Therefore, the electron affinity of the electron injection layer is more preferably set to a value within the range of 1.9 to 3.0 eV, and further preferably set to a value within the range of 2.0 to 2.5 eV. Further, the difference in electron affinity between the electron injection layer 15 and the organic light emitting layer 14 is preferably set to a value of 1.2 eV or less, and more preferably set to a value of 0.5 eV or less. The smaller the difference in electron affinity, the easier the electron injection from the electron injection layer 15 to the organic light emitting layer 14, and the organic EL element 106 with improved response performance can be configured.

(3) Energy gap The energy gap (band gap energy) of the electron injection layer 15 in the fourth embodiment is preferably set to a value of 2.7 eV or more, and more preferably set to a value of 3.0 eV or more. . Thus, by setting the value of the energy gap to a predetermined value or larger, for example, 2.7 eV or larger, it is possible to reduce the movement of holes beyond the organic light emitting layer 14 to the electron injection layer 15. Can do. Therefore, the efficiency of recombination of holes and electrons is improved, the emission luminance of the organic EL element 106 is increased, and the electron injection layer 15 itself can be prevented from emitting light.

(4) Structure Next, the structure of the electron injection layer 15 made of an inorganic compound will be described. The structure of the electron injection layer 15 is not particularly limited, and may be, for example, a single-layer structure, or a two-layer structure or a three-layer structure. Moreover, there is no restriction | limiting in particular also about the thickness of the electron injection layer 15, Various thickness can be employ | adopted according to a condition. Actually, for example, a value in the range of 0.1 nm to 1000 nm is preferable. This is because when the thickness of the electron injection layer 15 made of an inorganic compound is less than 0.1 nm, the electron injection property may be lowered or the mechanical strength may be lowered. On the other hand, when the thickness of the electron injection layer 15 made of an inorganic compound exceeds 1000 nm, the resistance becomes high, so that the response performance of the organic EL element 106 deteriorates, that is, high-speed response becomes difficult, or it is long in film formation. This is because it may take time. Accordingly, the thickness of the electron injection layer 15 made of an inorganic compound is more preferably set to a value within the range of 0.5 to 100 nm, and further preferably set to a value within the range of 1 to 50 nm.

(5) Formation Method Next, a method for forming the electron injection layer 15 will be described. The method for forming the electron injection layer 15 is not particularly limited as long as it can be formed as a thin film layer having a uniform thickness. For example, various methods such as a vacuum deposition method, a spin coating method, a casting method, an LB method, and a sputtering method can be applied.

[Fifth Embodiment]
Next, a fifth embodiment of the present invention will be described. In the fifth embodiment, even when a plurality of inorganic compounds are used, an anode layer 16 having a uniform composition ratio of constituent materials and excellent etching characteristics and transparency can be obtained. As a result, the present invention provides a manufacturing method in which an organic EL element having a low driving voltage and excellent in emission luminance and durability can be obtained efficiently. That is, the fifth embodiment is characterized in that the anode layer 16 is formed by using a specific target and a sputtering method. Further, in the fifth embodiment, for example, even when a plurality of organic light emitting materials are used, the organic light emitting layer 14 having a uniform composition ratio of the constituent materials can be obtained. As a result, the present invention provides a manufacturing method in which an organic EL element having a low driving voltage, high emission luminance, and excellent durability can be obtained efficiently. That is, the fifth feature of the fifth embodiment is that the organic light emitting layer 14 is formed from a plurality of organic compounds using a specific vacuum deposition method.

  In order to obtain an organic EL element having a characteristic that the composition ratio of the constituent materials is uniform, it is preferable that at least the anode layer 10 and the organic light emitting layer 14 are formed under consistent and identical vacuum conditions without being exposed to the atmosphere. . In the fifth embodiment, a third feature is that a vacuum chamber for performing a sputtering method and a vacuum chamber for performing a vacuum deposition method are shared. The reason is to obtain an organic EL element having a characteristic that the composition ratio of the constituent materials is uniform. Therefore, in the fifth embodiment, not only a heating apparatus and a substrate holding unit necessary for performing the sputtering method, but also a heating apparatus necessary for performing the vacuum vapor deposition method in one vacuum chamber. By providing a vapor deposition source or the like, the vacuum tube for performing the sputtering method and the vacuum tank for performing the vacuum vapor deposition method can be shared. As a modification of the fifth embodiment, it is also possible to employ a configuration in which a sputtering vacuum chamber and a vacuum deposition vacuum chamber are separately provided and connected in advance. According to such a modification, after the vacuum vapor deposition method is performed, the substrate is moved into the sputtering method vacuum chamber by a predetermined transfer device, thereby obtaining the same result as the case where the vacuum chamber is shared. In addition, the configuration of the organic EL element described in the fifth embodiment is the same as that of the fourth embodiment for easy understanding.

  According to the manufacturing method employed in the fifth embodiment, each layer shown below was formed by a corresponding manufacturing method.

Anode layer 10: High frequency magnetron sputtering method Inorganic thin film layer 12: High frequency magnetron sputtering method Hole transport layer 13: Vacuum deposition method Organic light emitting layer 14: Vacuum deposition method Electron injection layer 15: Vacuum deposition method Cathode layer 16: Vacuum deposition method ( 1) Formation of anode layer and inorganic thin film layer In forming the anode layer 10 and the inorganic thin film layer 12 by the high frequency magnetron sputtering method, the A group (A-1 group or A-2 group) and the B group (B-1 group or It is preferable to use a target composed of the compound of Group B-2). Specifically, the target must contain at least a group A (Group A-1 or Group A-2) and a group B (Group B-1 or Group B-2) at a predetermined ratio. Moreover, the target (average particle diameter of 1 μm or less) as a raw material is a solution method (coprecipitation method) (concentration: 0.01 to 10 mol / liter, solvent: polyhydric alcohol, precipitation forming agent: potassium hydroxide, etc.), After mixing uniformly by using a physical mixing method (stirrer: ball mill, bead mill, etc., mixing time: 1 to 200 hours), sintering (temperature 1200 to 1500 ° C., time 10 to 72 hours, more preferably, 24 to 48 hours) and further obtained by molding (press molding, HIP molding, etc.) is preferable. At this time, it is more preferable to set the temperature rising rate at the time of molding to a value within the range of 1 to 50 ° C./min. The target obtained by these methods has a characteristic that the composition ratio of the constituent materials is uniform. In addition, since composition ratio etc. can be adjusted only by sputtering conditions, the compound of A group (A-1 group or A-2 group) and B group (B-1 group or B-2 group) is separate from it. It is also preferable to perform sputtering.

The sputtering conditions are not particularly limited, but the plasma output is 0.3 to 4 W per 1 cm ² of the target surface area in an inert gas such as argon, and the degree of vacuum is 1 × 10 ⁻⁷ to 1 × 10 ^−. It is preferable to adopt the conditions of ³ Pa, a film formation rate of 0.01 to 50 nm / second, a film formation time of 5 to 120 minutes, and a substrate temperature of −50 to 300 ° C. This is because such sputtering conditions are economical, and the dense anode layer 16 and inorganic thin film layer 12 having a uniform film thickness can be formed.

(2) Formation of the organic light emitting layer 14 With reference to FIG.5 and FIG.6, the method of forming the organic light emitting layer 14 by evaporating a different vapor deposition material simultaneously is demonstrated. First, using the vacuum vapor deposition apparatus 201, a rotation axis 213A for rotating the substrate 203 is set on the substrate 203. Next, the vapor deposition sources 212A to 212F are respectively arranged at positions away from the rotation axis 213A of the substrate 203, and the substrate 203 is rotated. At the same time, vapor deposition is performed by simultaneously evaporating different vapor deposition materials from a plurality of vapor deposition sources 212A to 212F arranged to face the substrate 203. In this way, the organic light emitting layer 14 can be obtained.

  Here, the vacuum vapor deposition apparatus 201 shown in FIGS. 5 and 6 includes a vacuum chamber 210, a substrate holder 211 for fixing the substrate 203 installed in the upper portion of the vacuum chamber 210, and a lower portion of the substrate holder 211. And a plurality of (six) vapor deposition sources 212A to 212F for filling the vapor deposition material disposed opposite to each other. The inside of the vacuum chamber 210 can be maintained in a predetermined reduced pressure state by an exhaust means (not shown). The number of vapor deposition sources is six on the drawing, but is not limited to this, and may be five or less, or may be seven or more.

  In addition, the substrate holder 211 includes a holding unit 212 that supports the peripheral portion of the substrate 203 and is configured to hold the substrate 203 horizontally in the vacuum chamber 210. At the center portion of the upper surface of the substrate holder 211, a rotation shaft portion 213 for rotating (spinning) the substrate 203 is erected in the vertical direction. The rotation shaft portion 213 is connected to a motor 214 as rotation disturbance means, and the substrate 203 held by the substrate holder 211 is rotated together with the substrate holder 211 by the rotation operation of the motor 214 with the rotation shaft portion 213 as the rotation center. It is designed to rotate. That is, at the center of the substrate 203, the rotation axis 213A by the rotation shaft portion 213 is set in the vertical direction.

  Next, a method for depositing the organic light emitting layer 12 on the substrate 203 from two kinds of organic light emitting materials (host material and dopant material) using the vacuum vapor deposition apparatus 201 configured as described above will be specifically described. explain. First, a planar square substrate 203 as shown in FIG. 5 is prepared, and this substrate 203 is locked to the holding portion 212 of the substrate holder 211 to be in a horizontal state. In this regard, the fact that the substrate 203 shown in FIG. 5 is held in a horizontal state indicates that the substrate 203 is engaged with the holding portion 212 of the substrate holder 211 and is in a horizontal state.

  Here, when the organic light emitting layer 12 is formed, the host material and the dopant material are filled in the two adjacent vapor deposition sources 212B and 212C on the virtual circle 221, respectively. After filling, the inside of the vacuum chamber 210 is depressurized by the exhaust means until a predetermined degree of vacuum, for example, 1.0 × 10 −4 Torr. Next, the evaporation sources 212B and 212C are heated to simultaneously evaporate the host material and the dopant material from the respective evaporation sources 212B and 212C. At the same time, the motor 214 is caused to rotate and the substrate 203 is rotated along the rotation axis 213A at a predetermined speed, for example, 1 to 100 rpm. In this way, the organic light emitting layer 12 is formed by co-evaporating the host material and the dopant material while rotating the substrate 203. At this time, as shown in FIG. 6, the vapor deposition sources 212B and 212C are provided at a position shifted by a predetermined distance M in the horizontal direction from the rotation axis 213A of the substrate 203. In addition, the incident angle of the vapor deposition material such as dopant material to the substrate 203 can be regularly changed. Therefore, the vapor deposition material can be uniformly attached to the substrate 203, and a thin film layer having a uniform composition ratio of the vapor deposition material can be reliably formed within the film surface of the electron injection layer 15. For example, it is possible to form a thin film layer having a density unevenness of ± 10% (molar conversion). Further, by performing the vapor deposition in this manner, the substrate 203 does not have to be revolved, so that the space and equipment are not required, and the film formation can be performed economically with the minimum space. Here, revolving the substrate 203 means rotating around a rotating shaft other than the substrate, and requires a larger space than when rotating.

  In carrying out the co-evaporation, the shape of the substrate 203 is not particularly limited. As an example, as shown in FIG. 5, when the substrate 203 has a short flat plate shape and the sides of the substrate 203 have the same length, a virtual circle 221 centered on the rotation axis 213 </ b> A of the substrate 203. When a plurality of vapor deposition sources 212A to 212F are arranged along the circumference of the substrate, the radius of the virtual circle 221 is M, and the length of one side of the substrate 203 is L, M> (1/2) × L It is desirable to have a short flat plate shape that satisfies the above. On the other hand, when the lengths of the sides of the substrate 203 are not the same and different, the length of the longest side is set to L. With this configuration, the incident angles of the vapor deposition material with respect to the substrate 203 can be made the same from the plurality of vapor deposition sources 212A to 212F, so that the composition ratio of the vapor deposition material can be more easily controlled. Also, with this configuration, the vapor deposition material is evaporated at a constant incident angle with respect to the substrate 203, so that it does not enter perpendicularly and the uniformity of the composition ratio in the film plane is further improved. be able to.

  In carrying out the manufacturing method of the fifth embodiment, as shown in FIG. 5, a plurality of vapor deposition sources 212A to 212F are arranged on the circumference of a virtual circle 221 centered on the rotation axis 213A of the substrate 203. It is possible to arrange each of the vapor deposition sources 212A to 212F at an angle of 360 ° / n from the center of the virtual circle 221 when the number (number) of the plurality of vapor deposition sources 212A to 212F is n. preferable. For example, when six vapor deposition sources 212 are arranged, it is preferable to arrange them at an angle of 60 ° from the center of the virtual circle 221. With this arrangement, a plurality of vapor deposition materials can be sequentially stacked on each part of the substrate 203, so that thin film layers having different composition ratios can be easily formed in the thickness direction of the film. can do.

  Next, the compositional uniformity in the organic light emitting layer 14 formed by the above-described simultaneous vapor deposition method will be described in more detail. As an example, Alq is used as a host material, Cs is used as a dopant material, and a thin film layer having a thickness of about 1000 angstroms (setting value) is co-deposited under the following conditions while rotating the substrate 203 shown in FIG. 7 at 5 rpm. .

Alq deposition rate: 0.1-0.3 nm / s
Cs deposition rate: 0.1 to 0.3 nm / s
Alq / Cs film thickness: 1000 angstroms (setting value)
The chemical structural formula of Alq is shown in FIG.

  Next, the film thickness of the thin film layer obtained at the measurement points (4A to 4M) on the glass substrate 203 shown in FIG. 7 was measured using a stylus type film thickness meter, and Cs / Al (Al in Alq ) The composition ratio (atomic ratio) was measured using an X-ray photoelectron spectrometer (XPS). Note that the measurement points (4A to 4M) on the glass substrate 203 shown in FIG. 7 are obtained by dividing the surface of the substrate 203 into 16 equal parts in advance and setting square sections with a side length P of 50 mm. Arbitrary corners (13 places) in the section are used. The obtained results are shown in Table 1.

一方、ガラス基板２０３を回転させないほかは、上記同時蒸着方法と同様の蒸着条件において、厚さ約１０００オングストローム（設定値）の薄膜層を形成した。得られた薄膜層の測定点（４Ａ〜４Ｍ）におけるの膜厚及びＣｓ／Ａｌの組成比（原子比）を測定し、結果を表２に示す。

On the other hand, except that the glass substrate 203 was not rotated, a thin film layer having a thickness of about 1000 angstroms (set value) was formed under the same vapor deposition conditions as in the simultaneous vapor deposition method. The film thickness and the Cs / Al composition ratio (atomic ratio) at the measurement points (4A to 4M) of the obtained thin film layer were measured, and the results are shown in Table 2.

これらの結果から明らかなように、上述した同時蒸着方法によれば、基板２０３上の測定点（４Ａ〜４Ｍ）にて、膜厚が１００８〜１０９３オングストロームの範囲内という極めて均一な厚さで、かつ、Ｃｓ／Ａｌの組成比（原子比）が１．０〜１．１０の範囲内という極めて均一な組成比である薄膜層が得られることが確認された。一方、上述した同時蒸着方法と異なる製造方法を用いた場合、基板２０３上の測定点（４Ａ〜４Ｍ）にて、膜厚が８８４〜１０６７オングストロームの範囲内の値であり、Ｃｓ／Ａｌの組成比が０．６〜１．３の範囲内の値であることが確認された。

As is clear from these results, according to the above-described co-evaporation method, the film thickness is in the range of 1008 to 1093 angstroms at the measurement points (4A to 4M) on the substrate 203. In addition, it was confirmed that a thin film layer having a very uniform composition ratio of Cs / Al composition ratio (atomic ratio) in the range of 1.0 to 1.10. On the other hand, when a manufacturing method different from the above-described simultaneous vapor deposition method is used, the film thickness is a value in the range of 884 to 1067 angstroms at the measurement points (4A to 4M) on the substrate 203, and the composition of Cs / Al. The ratio was confirmed to be a value within the range of 0.6 to 1.3.

[Example 1]
(1) Preparation for manufacturing organic EL elements (creation of targets)
A powder of indium oxide and cerium oxide (average particle size of 1 μm or less) was placed in a wet ball mill container so that the Ce / (In + Ce) molar ratio was 0.05, and mixed and ground for 72 hours. Next, the obtained pulverized product was granulated and then press-molded into a size of 4 inches in diameter and 5 mm in thickness. After this was accommodated in a firing furnace, the target 1 for the anode layer 10 was manufactured by heating and firing at a temperature of 1400 ° C. for 36 hours.

(2) Formation of anode layer 10 Next, a transparent glass substrate having a thickness of 1.1 mm, a length of 25 mm, and a width of 75 mm and the obtained target 1 are placed in a vacuum chamber shared by the high-frequency sputtering apparatus and the vacuum evaporation apparatus. The high frequency sputtering apparatus was operated to form a transparent electrode film having a thickness of 75 nm as the anode layer 10 to obtain a substrate. In addition, in a state where the degree of vacuum is reduced to 3 × 10 ⁻¹ Pa, a gas in which oxygen gas is mixed into argon gas is sealed, and in this atmosphere, the ultimate degree of vacuum is 5 × 10 ⁻⁴ Pa, the substrate temperature is 25 ° C., Sputtering was performed under the conditions of an input power of 100 W and a film formation time of 14 minutes. Hereinafter, the glass substrate and the anode layer 10 are collectively referred to as a substrate. Subsequently, the substrate was ultrasonically cleaned with isopropyl alcohol, further dried in an N ₂ (nitrogen gas) atmosphere, and then cleaned with UV (ultraviolet light) and ozone for 10 minutes. In this state, the value of the ionization potential of the anode layer 10 in the substrate was measured using AC-1 (manufactured by Riken Keiki Co., Ltd.), and was 6.20 eV. Further, the light transmittance (wavelength 550 nm) of the substrate on which the anode layer 10 was formed was measured and found to be 89%.

(3) Treatment in a vacuum deposition apparatus A substrate is mounted on a substrate holder of a vacuum chamber, and then the inside of the vacuum chamber is depressurized to a vacuum degree of 1 × 10 ⁻⁶ Torr or less, and then the anode layer 10 of the substrate and inorganic On the thin film layer 12, a hole transport layer 13, an organic light emitting layer 14, an electron injection layer 15 and a cathode layer 16 were sequentially laminated to obtain an organic EL device. At this time, the same vacuum conditions were applied between the formation of the organic light emitting layer 14 and the formation of the cathode layer 16 without breaking the vacuum state.

  First, TBDB was vacuum deposited as a hole transport material by 60 nm. Next, DPVDPAN and D1 were co-deposited as a light emitting layer under vacuum at 40 nm. At this time, the deposition rate of DPVDPAN was 40 nm / s, and the deposition rate of D1 was 1 nm / s.

  The chemical structural formula of TBDB is shown in FIG. The chemical structural formula of DPVDPAN is also shown in FIG. The chemical structural formula of D1 is also shown in FIG.

  Subsequently, Alq was vacuum-deposited by 20 nm as an electron injection layer.

  Finally, Al and Li were vacuum-deposited to form the cathode layer 16 on the electron injection layer 15 to obtain an organic EL element. At this time, the deposition rate of Al was 1 nm / s, the deposition rate of Li was 0.01 nm / s, and the film thickness of Al / Li was 200 nm.

(4) Evaluation of organic EL element In the obtained organic EL element, the cathode layer 16 was a negative (-) electrode and the anode layer 10 was a positive (+) electrode, and a DC voltage of 4.8 V was applied between both electrodes. At this time, the current density was 2.0 mA / cm ² and the light emission luminance was 164 nit (cd / m ² ). It was also confirmed that the emission color was blue. Furthermore, as a durability evaluation, when a constant current drive was performed at 10 mA / cm ² , no leakage current was particularly observed even after 1000 hours had passed.

［実施例２］
実施例１におけるターゲット１のかわりに、酸化インジウムと、酸化スズと、酸化亜鉛と、酸化ネオジウムとからなる、インジウムのモル比（Ｉｎ／（Ｉｎ＋Ｓｎ＋Ｚｎ））が０．８であり、スズのモル比（Ｓｎ／（Ｉｎ＋Ｓｎ＋Ｚｎ））が０．１であり、亜鉛（Ｚｎ／（Ｉｎ＋Ｓｎ＋Ｚｎ））のモル比が０．１であるターゲット３を用いた。その他の製造条件は実施例１と同様にして有機ＥＬ素子を作成した。なお、陽極層１０のイオン化ポテンシャルの値は、５．８５ｅＶであった。得られた有機ＥＬ素子に実施例１と同様に、電極間に５．３Ｖの直流電圧を印加したところ、電流密度の値は２．０ｍＡ／ｃｍ²であり、発光輝度は１５８ｎｉｔであった。また、発光色は青色であることを確認した。

[Example 2]
Instead of the target 1 in Example 1, the molar ratio of indium (In / (In + Sn + Zn)) composed of indium oxide, tin oxide, zinc oxide, and neodymium oxide is 0.8, and the molar ratio of tin A target 3 having (Sn / (In + Sn + Zn)) of 0.1 and a zinc (Zn / (In + Sn + Zn)) molar ratio of 0.1 was used. Other manufacturing conditions were the same as in Example 1 to prepare an organic EL device. The ionization potential value of the anode layer 10 was 5.85 eV. When a direct current voltage of 5.3 V was applied between the electrodes in the same manner as in Example 1 to the obtained organic EL device, the current density value was 2.0 mA / cm ² and the light emission luminance was 158 nits. It was also confirmed that the emission color was blue.

[Example 3]
Instead of the target 1 in Example 1, the molar ratio (In / (In + Sn + Zn)) of indium consisting of indium oxide, tin oxide, zinc oxide, and samarium oxide is 0.8, and the molar ratio of tin (Sn / (In + Sn + Zn)) is 0.1, the molar ratio of zinc (Zn / (In + Sn + Zn)) is 0.1, and the molar ratio of samarium in the whole metal (Sm / (In + Sn + Zn + Sm)) is 0. .04, target 4, was used. Other manufacturing conditions were the same as in Example 1 to prepare an organic EL device. The value of the ionization potential of the anode layer 10 was 5.95 eV. When a direct-current voltage of 5.0 V was applied between the electrodes in the same manner as in Example 1 to the obtained organic EL element, the current density value was 2.0 mA / cm ² and the light emission luminance was 168 nits. It was also confirmed that the emission color was blue.

[Example 4]
Instead of the target 1 in Example 1, the molar ratio of indium (In / (In + Sn + Zn)) composed of indium oxide, tin oxide, zinc oxide, and europium oxide is 0.8, and the molar ratio of tin (Sn / (In + Sn + Zn)) is 0.1, the molar ratio of zinc (Zn / (In + Sn + Zn)) is 0.1, and the molar ratio of europium in the entire metal (Eu / (In + Sn + Zn + Eu)) is 0. A target 5 of .04 was used. Other manufacturing conditions were the same as in Example 1 to prepare an organic EL device. The value of the ionization potential of the anode layer 10 was 5.80 eV. When a direct current voltage of 5.1 V was applied between the electrodes in the same manner as in Example 1 to the obtained organic EL element, the current density value was 2.0 mA / cm ² and the light emission luminance was 165 nit. It was also confirmed that the emission color was blue.

[Example 5]
Instead of the target 1 in Example 1, the molar ratio (In / (In + Sn + Zn)) of indium consisting of indium oxide, tin oxide, zinc oxide, and terbium oxide is 0.8, and the molar ratio of tin (Sn / (In + Sn + Zn)) is 0.1, the molar ratio of zinc (Zn / (In + Sn + Zn)) is 0.1, and the molar ratio of terbium in the whole metal (Tb / (In + Sn + Zn + Tb)) is 0. A target 6 that was 0.06 was used. Other manufacturing conditions were the same as in Example 1 to prepare an organic EL device. The value of the ionization potential of the anode layer 10 was 5.84 eV. When a DC voltage of 5.1 V was applied between the electrodes in the same manner as in Example 1 to the obtained organic EL device, the current density value was 165 mA / cm ² and the light emission luminance was 95 nits. It was also confirmed that the emission color was blue.

[Example 6]
Instead of the target 1 in Example 1, the molar ratio of indium (In / (In + Sn + Zn)) made of indium oxide, tin oxide, zinc oxide, and fornium oxide is 0.8, and the molar ratio of tin (Sn / (In + Sn + Zn)) is 0.1, the molar ratio of zinc (Zn / (In + Sn + Zn)) is 0.1, and the molar ratio of fornium in the entire metal (Ho / (In + Sn + Zn + Ho)) is 0. .12 target 7 was used. Other manufacturing conditions were the same as in Example 1 to prepare an organic EL device. The value of the ionization potential of the anode layer 10 was 5.82 eV. When a direct current voltage of 5.1 V was applied between the electrodes in the same manner as in Example 1 to the obtained organic EL device, the current density value was 2.0 mA / cm ² and the light emission luminance was 166 nits. It was also confirmed that the emission color was blue.

[Example 7]
Instead of the target 1 in Example 1, the molar ratio of indium (In / (In + Sn + Zn)) composed of indium oxide, tin oxide, zinc oxide, and cerium oxide is 0.8, and the molar ratio of tin (Sn / (In + Sn + Zn)) is 0.1, the molar ratio of zinc (Zn / (In + Sn + Zn)) is 0.1, and the molar ratio of cerium in the whole metal (Ce / (In + Sn + Zn + Ce)) is 0. A target 8 of .06 was used. Other manufacturing conditions were the same as in Example 1 to prepare an organic EL device. The value of the ionization potential of the anode layer 10 was 5.98 eV. When a direct current voltage of 4.9 V was applied between the electrodes in the same manner as in Example 1 to the obtained organic EL element, the current density value was 2.0 mA / cm ² and the light emission luminance was 164 nits. It was also confirmed that the emission color was blue.

[Example 8]
Instead of the target 1 in Example 1, the molar ratio of indium (In / (In + Sn)) made of indium oxide, tin oxide, and cerium oxide is 0.9, and the molar ratio of tin (Sn / ( A substrate formed to a film thickness of 75 nm using a target 8 with In + Sn)) of 0.1 is mainly composed of zinc oxide, and the molar ratio of cerium to the entire metal (Ce / (Zn + Ce)) is 0.05. A substrate having a thickness of 20 nm formed using a target was used. Other manufacturing conditions were the same as in Example 1 to prepare an organic EL device. In addition, the value of the ionization potential of the anode layer 10 was 6.18 eV, and the transmittance was 79%. Further, in the same manner as in Example 1, a DC voltage of 4.8 V was applied between the electrodes of the obtained organic EL element. The current density at this time was 2.0 mA / cm ² , and the light emission luminance was 162 nit (cd / m ² ). It was also confirmed that the emission color was blue. Furthermore, as a durability evaluation, when a constant current drive was performed at 10 mA / cm ² , no leakage current was particularly observed even after 1000 hours had passed.

[Comparative Example 1]
Instead of the target 1 in Example 1, the indium molar ratio (In / (In + Sn + Zn)) composed of indium oxide, tin oxide, and zinc oxide is 0.6, and the tin molar ratio (Sn / ( In + Sn + Zn)) was 0.3, and a target 9 having a zinc (Zn / (In + Sn + Zn)) molar ratio of 0.1 was used. Other than that, an organic EL device was prepared in the same manner as in Example 1. The value of the ionization potential of the anode layer 10 was 5.23 eV. When a DC voltage of 6.0 V was applied between the electrodes in the same manner as in Example 1 to the obtained organic EL device, the current density value was 2.0 mA / cm ² and the light emission luminance was 166 nits. It was also confirmed that the emission color was blue.

DESCRIPTION OF SYMBOLS 10 Anode layer 12 Inorganic thin film layer 13 Hole transport layer 14 Organic light emitting layer 15 Electron injection layer 16 Cathode layer 30 Substrate 100, 102, 104, 106 Organic EL element 201 Vacuum vapor deposition apparatus 203 Substrate 210 Vacuum chamber 211 Substrate holder 212 Holding part 212A, 212B, 212C, 212D, 212E, 212F Deposition source 213 Rotating shaft 213A Rotating axis 214 Motor 221 Virtual circle

Claims (19)

An organic electroluminescent element substrate comprising at least an electrode layer and a substrate, wherein the electrode layer is at least one compound selected from the following group A-1 and at least one compound selected from the group B-1 A substrate for an organic electroluminescence element, comprising:
Group A-1: chalcogenide, oxynitride, or nitride of Si, Ge, Sn, Pb, Ga, In, Zn, Cd, and Mg.
Group B-1: chalcogenides, oxynitrides or nitrides of lanthanoid elements. An organic electroluminescent element substrate comprising at least an electrode layer and a base material, wherein the electrode layer is at least one compound selected from the following group A-2 and at least one compound selected from the group B-2 A substrate for an organic electroluminescence element, comprising:
Group A-2: Ge, Sn, Pb, Ga, In, Zn, Cd, Mg chalcogenide, oxynitride, or nitride.
Group B-2: Chalcogenides of lanthanoid elements. The substrate for organic electroluminescence elements according to claim 1, wherein the electrode layer is an anode layer. The substrate for an organic electroluminescence element according to claim 1, wherein the electrode layer is a cathode layer. The substrate for an organic electroluminescence element according to claim 1, wherein the electrode layer has a specific resistance value of less than 1 Ω · cm. The substrate for an organic electroluminescence device according to any one of claims 1 to 5, wherein the compound of the group A-1 or the group A-2 is any one of Sn, In, and Zn chalcogenides or nitrides. The organic electroluminescence device according to any one of claims 1 to 6, wherein the compound of the group B-1 or the group B-2 is any one of an oxide of Ce, Nd, Sm, Eu, Tb, and Ho. Substrate. The total amount of the electrode layer is 100 at. %, The content of the compound of the B-1 group or B-2 group is 0.5 to 30 at. The substrate for organic electroluminescence elements according to claim 1, wherein the substrate is a value within a range of%. The substrate for organic electroluminescence elements according to any one of claims 1 to 8, wherein the thickness of the electrode layer is set to a value within a range of 1 to 100 nm. In the organic electroluminescence device having a structure in which at least an anode layer, an organic light emitting layer, and a cathode layer are sequentially laminated, the anode layer and the cathode layer, or any one of the electrode layers is selected from the following group A-1. An organic electroluminescence device comprising at least one selected compound and at least one compound selected from the following group B-1.
Group A-1: chalcogenide, oxynitride, or nitride of Si, Ge, Sn, Pb, Ga, In, Zn, Cd, Mg Group B-1: chalcogenide, nitric oxide, or nitride of a lanthanoid element. In the organic electroluminescence device having a structure in which at least an anode layer, an organic light emitting layer, and a cathode layer are sequentially laminated, the anode layer and the cathode layer, or any one of the electrode layers is selected from the following group A-2. An organic electroluminescence device comprising at least one compound selected and at least one compound selected from the following group B-2.
Group A-2: Ge, Sn, Pb, Ga, In, Zn, Cd, Mg chalcogenide, oxynitride, or nitride B-2 group: Chalcogenide of lanthanoid element. The organic electroluminescence device according to claim 10 or 11, wherein the anode layer and / or the cathode layer has a specific resistance value of less than 1 Ω · cm. The organic electroluminescence device according to any one of claims 10 to 12, wherein the compound of the A-1 group or the A-2 group is any one of Sn, In, and Zn chalcogenides or nitrides. 14. The compound according to claim 12, wherein the compound of Group B-1 or Group B-2 is an oxide of any substance of Ce, Nd, Sm, Eu, Tb, and Ho. Organic electroluminescence device. The total amount of the electrode layer is 100 at. %, The content of the compound of the B-1 group or B-2 group is 0.5 to 30 at. The organic electroluminescence element according to claim 10, wherein the organic electroluminescence element is a value within a range of%. The organic electroluminescence element according to any one of claims 10 to 15, wherein the film thickness of the electrode layer is a value within a range of 1 to 100 nm. At least one compound selected from the A-1 group and the B-1 group between the anode layer and the organic light emitting layer and / or between the cathode layer and the organic light emitting layer. An inorganic thin film layer containing at least one compound selected from: or an inorganic thin film layer containing at least one compound selected from Group A-2 and at least one compound selected from Group B-2 The organic electroluminescent element according to claim 10, which is provided. The organic light-emitting layer comprises at least one of an aromatic compound having a styryl group represented by any one of the following general formulas (chemical formula 1) to (chemical formula 3). The organic electroluminescent element according to claim 1.

Here, in the general formula (Chemical Formula 1), Ar ¹ is an aromatic group having 6 to 40 carbon atoms, and Ar ² , Ar ³ , and Ar ⁴ are each a hydrogen atom or 6 to 40 carbon atoms. It is an aromatic group, and at least one of Ar ¹ , Ar ² , Ar ³ , and Ar ⁴ is an aromatic group, and the condensation number n is an integer of 1-6.

Here, in the general formula (Chemical Formula 2), Ar ⁵ is an aromatic group having 6 to 40 carbon atoms, and Ar ⁶ and Ar ⁷ are each a hydrogen atom or an aromatic group having 6 to 40 carbon atoms. Yes, at least one of Ar ⁵ , Ar ⁶ and Ar ⁷ is substituted with a styryl group, and the condensation number m is an integer of 1 to 6.

Here, in the general formula (Chemical Formula 3), Ar ⁸ and Ar ¹⁴ are aromatic groups having 6 to 40 carbon atoms, and Ar ^{9 to} Ar ¹³ are each a hydrogen atom or an aromatic group having 6 to 40 carbon atoms. And at least one of Ar ^{8 to} Ar ¹⁴ is substituted with a styryl group, and the condensation numbers p, q, r, and s are each 0 or 1. 19. The method of manufacturing an organic electroluminescence element according to claim 10, wherein the electrode layer is formed by a sputtering method, and the organic light emitting layer is formed by a vacuum evaporation method. Manufacturing method of luminescence element.

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