JP2007220394A - Organic electroluminescent device, manufacturing method therefor and display device, and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily adjust the transport property of a carrier. <P>SOLUTION: The manufacturing method includes a process for forming a primary organic layer 103 by a liquid phase process, a process for conducting an insolubilizing treatment to the primary organic layer 103 and a process for forming a secondary organic layer 104 on the insolubilized primary organic layer 103 by the liquid phase process. Insolubilizing treatment condition of the primary organic layer 103 is adjusted based on the transport property of the carrier in the secondary organic layer 104. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to an organic EL device, a manufacturing method thereof, a display device, and an electronic apparatus.

An organic electroluminescence (EL) element has a structure in which a plurality of thin films containing an organic material are sandwiched between a first electrode and a second electrode, and carriers injected from these two electrodes are contained in the organic thin film. The element emits light when recombined with.
This organic EL element (organic EL device) has features such as thinness and light weight, and is expected to be applied to a display. As a manufacturing method of an organic EL element, generally, a dry process such as a vacuum deposition method, a wet process represented by a spin coating method, a droplet discharge method (inkjet method), and the like can be given. Organic EL by stacking organic layers
Forming device.

Among these manufacturing processes, the wet process (liquid phase method) is a technique that has attracted attention because it is possible to manufacture a large-area organic EL panel, but it is necessary to stack a plurality of organic layers. Therefore, it is necessary to apply and laminate different solvents alternately so as not to dissolve each other between adjacent layers, or to perform insolubilization treatment so as not to dissolve in the solvent after forming an organic layer. .

Therefore, for example, in Patent Document 1, as a hole injection layer or a hole transport layer of an organic EL element,
A liquid containing a polythiophene derivative and a silane coupling agent is formed by a coating method,
A technique for thermosetting is disclosed.
Patent Document 2 uses a polymer having a carrier transporting property or a light emitting property containing a low-molecular crosslinking agent having a double bond group, an epoxy group, or a cyclic ether group, ultraviolet irradiation, electron beam irradiation, plasma irradiation, Alternatively, a technique for crosslinking by heating is disclosed.
JP 2000-208254 A JP-A-2005-243300

However, the following problems exist in the conventional technology as described above.
In an organic EL device, it is difficult to maintain a balance between electrons and holes injected from two electrodes. For example, when the light emitting structure in the light emitting layer is changed by changing the material used in order to change the emission spectrum, the transport ability of electrons and holes changes at the same time. Therefore, since the light-emitting materials having different emission colors have different electron and hole transport capabilities, even when the same hole injection layer or hole transport layer is used, it is optimal for one of the light-emitting layers. Even in the case of carrier characteristics, it is not necessarily optimal for other light emitting layers, and it has been difficult to maintain carrier balance between the light emitting layers of the respective colors.

Therefore, in order to maintain the carrier balance, it may be possible to adjust the carrier transport property by appropriately changing the light emitting material, the hole injection layer forming material, the hole transport layer forming material, etc., but it has various light emitting structures. If the material is changed for each organic EL device, the production efficiency will drop significantly.
Moreover, the problem that a manufacturing cost rises will arise.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide an organic EL device that can easily adjust carrier transportability, a manufacturing method thereof, a display device, and an electronic apparatus.

In order to achieve the above object, the present invention employs the following configuration.
The method for producing an organic EL device of the present invention is a method for producing an organic EL device in which a light emitting layer emits light by a carrier transported through an organic layer, the step of forming a first organic layer by a liquid phase method, , A step of insolubilizing the first organic layer, and the first insolubilized first
And forming a second organic layer on the organic layer by a liquid phase method, and adjusting the insolubilization condition of the first organic layer based on the transport property of the carrier in the second organic layer It is characterized by.

Therefore, in the manufacturing method of the organic EL device according to the present invention, the insolubilization condition is adjusted so that the organic EL device is not completely insolubilized with respect to the second organic layer. Therefore, when the liquid containing the second organic layer forming material is applied onto the first organic layer, the first organic layer forming material is eluted into the solution of the liquid so that the second organic layer has the first A layer in which the second organic layer forming material is mixed is formed. Since the first organic layer forming material originally has a carrier transport property, the material is eluted into the second organic layer, whereby the carrier transport property in the second organic layer can be increased. Therefore, it becomes possible to easily adjust the carrier transport characteristics in the second organic layer by changing the elution amount of the first organic layer forming material in accordance with the insolubilization treatment conditions of the first organic layer.

Moreover, in this invention, the structure which makes the said insolubilization process conditions mutually differ between several said light emitting layers from which a light emission characteristic differs can also be employ | adopted suitably.
Thus, in the present invention, by setting the insolubilization treatment condition for each light emitting layer, it becomes possible to control the carrier transport property according to the light emitting property, and easily maintain the carrier balance among the plurality of light emitting layers. be able to.

Further, in this case, the first organic layer corresponding to the light emitting layer having the first light emitting characteristics is deposited and subjected to the insolubilization treatment, and then the first light emitting layer corresponding to the light emitting layer having the second light emitting characteristics. A procedure for forming an organic layer and applying the insolubilization treatment can be employed.
The insolubilization treatment may be a procedure including heat treatment.

As a result, in the present invention, even when the insolubilization treatment is performed collectively on the first organic layer corresponding to the plurality of light emitting layers having different light emission characteristics, such as heat treatment, different light emission characteristics. The insolubilized state of the first organic layer can be made different for each light emitting layer.
As described above, after the insolubilization treatment is performed on the first organic layer corresponding to the light emitting layer having the first light emitting characteristics, the first organic layer corresponding to the light emitting layer having the second light emitting characteristics is formed. When forming the film, it is preferable to adopt a droplet discharge method in which a liquid containing the first organic layer forming material can be selectively applied to each light emitting layer.

In the present invention, after the first organic layer corresponding to the light emitting layer having the first light emitting characteristics and the first organic layer corresponding to the light emitting layer having the second light emitting characteristics are collectively formed. The procedure for applying the insolubilization treatment to the first organic layer under the different insolubilization treatment conditions can also be suitably employed.
The insolubilization process may be a procedure including an energy light irradiation process.

Thereby, in this invention, when the insolubilization process can be selectively performed on the first organic layer by using a mask or the like as in the energy light irradiation process, the light emission having the first light emission characteristic and the second light emission characteristic. Since the insolubilized state of the first organic layer corresponding to the layer can be easily changed, these first organic layers can be formed in a lump.
As energy light used for the irradiation treatment, ultraviolet light, electron beam, plasma light, or the like can be selected.

The insolubilization treatment is preferably a procedure including a treatment for causing cross-linking between the molecules of the material constituting the first organic layer.
Thereby, in this invention, the part which is not bridge | crosslinked completely with respect to a 2nd organic layer can be formed by adjusting insolubilization conditions (crosslinking process conditions). Therefore, when the liquid containing the second organic layer forming material is applied on the first organic layer, the first that is not crosslinked by the crosslinking reaction.
By elution of the organic layer forming material into the liquid solution, a layer in which the first and second organic layer forming materials are mixed is formed in the second organic layer. Since the first organic layer forming material originally has a carrier transport property, the material is eluted into the second organic layer, whereby the carrier transport property in the second organic layer can be increased. Therefore, according to the insolubilization process conditions of the first organic layer, the first
By changing the crosslinking rate of the organic layer forming material, that is, the elution amount, the carrier transport property in the second organic layer can be easily adjusted.

In addition, as a crosslinking process, the 1st organic layer forming material can be made to contain a crosslinking agent, and the process of the conditions which the said crosslinking agent is activated can also be performed.
It is.
As the carrier transporting organic material, a triphenylamine derivative, a polythiophene derivative, or the like can be used. As the crosslinkable organic material, a silane coupling crosslinking agent, a crosslink containing a double bond group, an epoxy group, a cyclic ether group, or the like. An agent can be used.

As one of the first organic layer and the second organic layer, in addition to a hole transport layer, a hole injection layer, an electron transport layer, and an electron injection layer, the light emitting layer can be used.

On the other hand, the organic EL device of the present invention is an organic EL device in which a light emitting layer emits light by carriers transported through an organic layer, the first organic layer formed by a liquid phase method, and the liquid phase method. And a second organic layer formed on the first organic layer, and the second organic layer is formed on the basis of the transport property of the carrier in the second organic layer and the first organic layer forming material. It has a mixed organic layer mixed with the second organic layer forming material.

Therefore, in the present invention, by eluting the first organic layer forming material into the liquid solution,
By forming a layer in which the first and second organic layer forming materials are mixed in the second organic layer, the first organic layer forming material originally having carrier transportability is eluted into the second organic layer, The carrier transportability in the two organic layers can be increased. Therefore, it is possible to easily adjust the carrier transport characteristics in the second organic layer by changing the elution amount of the first organic layer forming material and adjusting the mixing ratio.

As the mixed organic layer, a configuration in which the insolubilized state of the first organic layer with respect to the second organic layer is adjusted and the first organic layer forming material and the second organic layer forming material are mixed can be suitably employed. .
Accordingly, in the present invention, by adjusting the insolubilized state, the mixing ratio of the first organic layer forming material and the second organic layer forming material is adjusted, and the carrier transport property in the second organic layer is easily adjusted. It becomes possible to do.

Moreover, in this invention, the structure from which the said insolubilization state mutually differs between several said light emitting layers from which a light emission characteristic differs can be employ | adopted suitably.
As a result, in the present invention, by setting the insolubilization treatment conditions for each light emitting layer, it becomes possible to control the carrier transport suppression according to the light emission characteristics, and easily maintain the carrier balance among the plurality of light emitting layers. be able to.

As one of the first organic layer and the second organic layer, in addition to a hole transport layer, a hole injection layer, an electron transport layer, and an electron injection layer, the light emitting layer can be used.

The display device of the present invention is characterized by including the organic EL device described above, and the electronic device of the present invention is characterized by including the display device described above. .
Therefore, according to the present invention, it is possible to obtain a display device and an electronic device that can easily maintain a carrier balance, have excellent productivity, and contribute to a reduction in manufacturing cost.

Hereinafter, embodiments of an organic EL device, a manufacturing method thereof, a display device, and an electronic device according to the present invention will be described with reference to FIGS.
In each drawing used for the following description, the scale of each member is appropriately changed to make each member a recognizable size.

(First embodiment)
FIG. 1 is a cross-sectional view of the main part showing the configuration of an organic EL element (organic EL device) 100 manufactured using the manufacturing method of the present invention.
This organic EL element 100 has an anode (first electrode) 102 and a cathode (second electrode) 105 on a substrate 101, and an organic layer 110 is provided between the anode 102 and the cathode 105. It is.

This organic EL element 100 has an anode (first electrode) 102 and a cathode (second electrode) 105 on a substrate 101, and an organic layer 110 is provided between the anode 102 and the cathode 105. It is. The organic layer 110 is configured by laminating a hole injection / transport layer (first organic layer) 103 and a light emitting layer (second organic layer) 104. The organic EL element 100 is of a bottom emission method in which light emitted from the light emitting layer 104 is emitted from the substrate 101 side.

The base 101 is configured by forming a drive element (not shown) made of a TFT element, various wirings (not shown), etc. on a transparent substrate (not shown) such as a glass substrate. In addition, an anode 102 is formed on various wirings via an insulating layer or a planarizing film.
The anode 102 is formed by patterning on the substrate 101 and is connected to a driving element made of a TFT element, the various wirings, etc. In this embodiment, ITO (Indium Tin O 2) is used.
xide).

The hole injection / transport layer 103 is formed on the entire surface of the substrate 101 on which the anode 102 is formed. The hole injection / transport layer 103 transports holes injected from the anode 102 to the light emitting layer 104.
A known material can be used for injection. For example, triphenylamine derivatives, polythiophene derivatives, polyaniline, polypyrrole, and the like can be used. More specifically, 3,4-polyethylenediosithiophene / polystyrene sulfonic acid (PEDOT / PSS) or the like can be used, and materials having good carrier transportability (hole transportability) and silane coupling cross-linking. And a crosslinking agent containing a double bond group, a cyclic ether group and the like.

The light-emitting layer 104 emits light having a wavelength in a predetermined band by combining electrons injected from the cathode 105 and holes injected from the hole injection / transport layer 103. Specific examples of the material of the light emitting layer 104 include polyfluorene derivatives (PF) and polyparaphenylene vinylene derivatives (PP
V), polyparaphenylene derivatives (PPP), polyvinylcarbazole (PVK), polythiophene derivatives, and polysilane-based high molecular organic materials such as polymethylphenylsilane (PMPS) are preferably used.

In addition, these polymer organic materials include polymer organic materials such as penylene dyes, coumarin dyes, rhodamine dyes, rubrene, perylene, 9,10-diphenylanthracene,
A low molecular organic material such as tetraphenylbutadiene, Nile red, coumarin 6, or quinacridone may be doped.

The cathode 105 includes a metal having a low work function that can efficiently inject electrons into the light-emitting layer 104, such as a metal material such as magnesium (Mg) or calcium (Ca), and aluminum (
It is formed by laminating a metal having a low electric resistance such as Al), gold (Au), silver (Ag), or the like. A sealing layer (not shown) is formed on the cathode 105.

Next, a method for manufacturing the organic EL element 100 having such a configuration will be described with reference to FIGS. 2 and 3 are explanatory views showing one manufacturing process of the organic EL element 100. FIG.
[Substrate processing process]
First, in the same manner as in the prior art, TFT elements and various wirings are formed on a substrate 101 made of glass, and further, an interlayer insulating layer and a planarizing film are formed, and then ITO is formed by vapor deposition, etc.
Further, the anode 102 is formed by patterning. As a result, the anode 102 is formed on the substrate 101 as shown in FIG. Thereafter, after cleaning the substrate on which the anode 102 is formed, oxygen plasma treatment is performed at atmospheric pressure to modify the substrate surface to be hydrophilic.
Thereby, the work function of the anode 102 can be raised.

[Hole Injection / Transport Layer Formation Step (First Organic Layer Formation Step)]
Next, the hole injection / transport layer 103 is formed on the entire surface of the substrate 101 on which the anode 102 is formed. Here, a liquid material in which a hole injecting / transporting layer forming material (first organic layer forming material) is dissolved or dispersed in a solvent or a dispersion medium is first formed into a predetermined film thickness by a spin coating method. As shown in FIG. 2 (b), a pre-hole injection / transport layer 103a is formed.

Subsequently, insolubilization treatment of the pre-hole injection / transport layer 103a is performed (insolubilization treatment step). Specifically, as shown in FIG. 2C, the substrate 10 on which the pre-hole injection / transport layer 103a is formed.
1 is placed on a heated hot plate 120, and a baking process (heating process) is performed. By such a baking treatment, as shown in FIG. 2 (d), the pre-hole injection / transport layer 103a becomes the base 1
The 01 side is insolubilized to form an insolubilized layer 103b. That is, the hole injection / transport layer 10
Thus, an insolubilized layer 103b that is insoluble in the organic solvent (specific solvent) used in the step of forming the light emitting layer 104 disposed on the substrate 3 is formed.

The pre-hole injection / transport layer 103a is insolubilized at a part on the hot plate 120 side, and is heated on the insolubilization layer 103b on the side opposite to the hot plate 120 (that is, insolubilization treatment condition). 2), a part of the pre-hole injection / transport layer 103a that is not completely insolubilized remains as shown in FIG. 2D. Here, as the pre-hole injection / transport layer 103a, a layer showing solubility (easily soluble) with respect to a solvent (specific solvent) is used.

Here, the mechanism by which a part of the pre-hole injecting / transporting layer 103a is insolubilized by the firing process is as follows. That is, for the molecules of the material constituting the pre-hole injection / transport layer 103a, the insolubilized layer 103b is generated by causing cross-linking between the molecules. In this embodiment, pre-hole injection / The transport layer 103a contains the cross-linking agent, and heat treatment is performed under a condition that activates the cross-linking agent. In this case, it is not limited to heat treatment, and it is also possible to activate the crosslinking agent by performing ultraviolet irradiation treatment or the like.

Moreover, as a crosslinking process, the functional group which can be bridge | crosslinked is introduce | transduced with respect to the pre hole injection / transport layer 103a, and the heat processing of the conditions on which the functional group is activated can be performed. Even in this case, the functional group can be activated by, for example, ultraviolet irradiation.

By performing the insolubilization treatment as described above, a part of the pre-hole injection / transport layer 103a becomes the insolubilization layer 103b, and a part of the pre-hole injection / transport layer 103a remains on the insolubilization layer 103b (FIG. 2 (d)).

[Light emitting layer forming step (second organic layer forming step)]
Next, as shown in FIG. 3A, a light emitting layer forming material (second organic layer forming material) is formed on the hole injecting / transporting layer 103 having a prehole injection / transporting layer 103a as a dissolved layer in part. Is formed in a predetermined film thickness by a spin coating method, and then a baking treatment is performed to evaporate the solvent, whereby the light emitting layer 104 is formed.

Here, when a liquid containing the light emitting layer forming material is applied onto the hole injection / transport layer 103,
Since the hole injection / transport layer 103 is not completely insolubilized because the pre-hole injection / transport layer 103a remains, the hole injection / transport layer forming material contained in the pre-hole injection / transport layer 103a Is eluted into the liquid containing the light emitting layer forming material, whereby a layer (mixed organic layer) in which the light emitting layer forming material and the hole injection / transport layer forming material are mixed is formed in the light emitting layer 104. Since this hole injecting / transporting layer forming material originally has a hole transporting property (carrier transporting property), when this material is eluted into the light emitting layer 104, the light emitting layer 104 is selected according to the elution amount. As a result, the hole transportability with respect to the substrate increases.

[Cathode formation process]
Next, Ca and Al are sequentially laminated on the light emitting layer 104 by vacuum vapor deposition to form a cathode 105 composed of a Ca layer and an Al layer, as shown in FIG. Then, the sealing process is performed and the organic EL element 100 of this embodiment shall be manufactured.

(Example)
A TFT element and various wirings are formed on a substrate 101 made of glass, and further, an interlayer insulating layer and a flattening film are formed. Then, ITO is formed by vapor deposition and the like, and then the anode 102 is formed by patterning. did. Thereafter, after cleaning the substrate on which the anode 102 was formed, oxygen plasma treatment was performed at atmospheric pressure to modify the substrate surface to be hydrophilic.

Next, a solution containing a hole injection / transport layer forming material was applied to the substrate 101 on which the anode 102 was formed by spin coating. As this solution, in a mixed solvent of methanol and tetrahydrofuran (THF), poly (9,9-dioctylfluorene-2,7-diyl) -alt- (N, N′-bis (4-tertiary-butylphenyl) -N, N′-diphenylbenzidine-4 ′, 4 ″ -diyl) (hereinafter referred to as PF8−)
(TPD) and γ-glycidyloxypropyltrimethoxysilane was added and dissolved as a silane coupling agent.

Next, a plurality of (here, five) substrates 101 to which the above solution has been applied are transferred to 120 to 200.
The temperature was varied between ° C. and heated on a hot plate in a nitrogen atmosphere for 1 hour each.
After measuring the film thickness of the hole injection / transport layer in each substrate 101, the film was immersed in a THF solvent for about 1 minute and rinsed, and the film thickness was measured again. And the film thickness after the rinse with respect to the film thickness before rinse was made into the insolubilization rate.

The insolubilization rate with respect to the crosslinking reaction temperature at this time is shown in FIG.
As shown in this figure, the insolubilization rate increases as the cross-linking reaction temperature increases.
It became insoluble in THF at a crosslinking reaction temperature of 0 ° C. (insolubilization rate 100%).

Next, the organic EL device 100 was manufactured using the substrate 101 that had been insolubilized at the five crosslinking reaction temperatures, and the current density at 8 V was measured. As shown in FIG. As a result, the lower the temperature, the higher the current density.

As a comparative example, the hole injection / transport layer after the element having no light emitting layer 104 with respect to the organic EL element 100 shown in FIG. 1 is heated at the above five crosslinking reaction temperatures and rinsed with THF. The film thickness was made the same, and current density-voltage characteristics were measured.
As a result, there was no change in the measured value of the current density-voltage characteristic even when the crosslinking reaction temperature was changed. Therefore, the result shown in FIG. 5 shows the amount of the hole injection / transport layer forming material eluted in the light emitting layer 104. It is assumed that the hole transport property (carrier transport property) in the light emitting layer 104 is changed due to the difference.

As described above, in the present embodiment, the hole transport characteristics can be easily adjusted by changing (adjusting) the insolubilization treatment conditions for the hole injection / transport layer 103. In other words, in order to obtain a desired light emission characteristic, in order to generate a hole transport characteristic corresponding to this light emission characteristic, the hole injection / transport layer 103 is subjected to an insolubilization treatment under a processing condition according to the hole transport characteristic. If you apply it,
Therefore, in the present embodiment, when changing the light emission characteristics, even if it is necessary to change the carrier transport characteristics, for example, the heating temperature during the insolubilization treatment without changing the light emitting material and the hole injection / transport layer forming material. Can be easily handled by a simple task of setting the temperature to an appropriate temperature.
A decrease in production efficiency and an increase in manufacturing cost can be prevented.

(Second Embodiment)
Next, a second embodiment of the organic EL device will be described.
In the present embodiment, an organic EL device that has a plurality of pixel areas and emits light in a plurality of emission colors in each pixel area with different emission characteristics will be described.

FIG. 6 shows an enlarged view of the cross-sectional structure of the display region in the organic EL device 100. FIG. 6 shows three pixel regions A. The organic EL device 100 is configured by sequentially laminating a circuit element unit 14 in which a circuit such as a TFT is formed on a substrate 2 and an EL element unit 11 in which an organic layer (light emitting unit) 110 is formed. Yes.
In the organic EL device 100, light emitted from the organic layer 110 to the substrate 2 side is transmitted through the circuit element unit 14 and the substrate 2 and emitted to the lower side (observer side) of the substrate 2. Light emitted from 110 to the opposite side of the substrate 2 is reflected by the cathode 12, passes through the circuit element unit 14 and the substrate 2, and is emitted to the lower side (observer side) of the substrate 2.
Note that by using a transparent material for the cathode 12, light can be emitted from the cathode 12 side.

In the circuit element portion 14, a base protective film 2c made of a silicon oxide film is formed on the substrate 2,
An island-shaped semiconductor film 141 made of polycrystalline silicon is formed on the base protective film 2c. Note that a source region 141a and a drain region 141b are formed in the semiconductor film 141 by high-concentration P ion implantation, and a portion where P is not introduced is a channel region 141c.
Further, a transparent gate insulating film 142 that covers the base protective film 2c and the semiconductor film 141 is formed in the circuit element portion 14, and a gate electrode made of Al, Mo, Ta, Ti, W, or the like is formed on the gate insulating film 142. 143, and a transparent first interlayer insulating film 144a and a second interlayer insulating film 144b are formed on the gate electrode 143 and the gate insulating film 142. Gate electrode 1
43 is provided at a position corresponding to the channel region 141 c of the semiconductor film 141.

Further, contact holes 145 and 146 connected to the source / drain regions 141a and 141b of the semiconductor film 141 are formed in the first and second interlayer insulating films 144a and 144b, and the contact holes 145 and 146 are formed in the contact holes 145 and 146, respectively. Each is embedded with a conductive material.
On the second interlayer insulating film 144b, a transparent pixel electrode 111 made of ITO or the like is formed by patterning into a predetermined shape, and one contact hole 145 is connected to the pixel electrode 111.
The other contact hole 146 is connected to the power supply line 163.
In this manner, the thin film transistor 123 connected to each pixel electrode 111 is formed in the circuit element unit 14.

The EL element unit 11 includes an organic layer 110 stacked on each of the plurality of pixel electrodes 111... And a bank unit 1 provided between each pixel electrode 111 and the organic layer 110 to partition each organic layer 110.
12 and a counter electrode (cathode) 12 formed on the organic layer 110.
Here, the pixel electrode 111 is formed of a transparent conductive material, for example, ITO, and is patterned into a substantially rectangular shape in plan view. A bank portion 112 is provided between the pixel electrodes 111.

The bank 112 is composed of an inorganic bank layer 112a made of SiO ₂ or the like on the substrate 2 side, and an organic bank layer 112b formed on the inorganic bank layer 112a.
The inorganic bank layer 112a is formed so as to ride on the peripheral edge of the pixel electrode 111, and is arranged so that the periphery of the pixel electrode 111 and the inorganic bank layer 112a are planarly overlapped in a plan view. It has a structure. The organic bank layer 112b is also disposed so as to overlap with a part of the pixel electrode 111 in a plan view.
In addition, an opening 112c is formed in the organic bank layer 112b, and a functional layer forming material is disposed in the opening 112c to form a film as will be described later, whereby the organic layer 110 made of the functional layer is formed. It is supposed to be formed. The organic bank layer 112b is formed of a heat resistant and solvent resistant material such as an acrylic resin or a polyimide resin.

The organic layer 110 is disposed between the pixel electrode (anode) 111 and the counter electrode (cathode) 12, thereby constituting an organic EL element together with the pixel electrode 111 and the counter electrode 12. Here, in the present embodiment, in order to achieve full-color display with different light emission characteristics, an organic EL element that is a pixel R having red light emission characteristics, an organic EL element that is a pixel G having green light emission characteristics, and a blue color And an organic EL element to be a pixel B having the above light emission characteristics.

In the present embodiment, each of these three types of organic EL elements is used as the organic layer 110.
The hole injection / transport layer (first organic layer) 151 (151R, 151G, 151B) and the light emitting layer (second organic layer) 150 (150R, 150G, 150B) are provided. These hole injection / transport layers 151 (151R, 151G, 151B) are formed of the same material as the hole injection / transport layer 103 of the first embodiment. In addition, the light emitting layer 150 (150R, 15
0G, 150B) is also formed of the same material as that of the light emitting layer 104 of the first embodiment.

Next, in order to manufacture the organic EL device 100 having such a configuration, first, a TFT element (thin film transistor 123) and various wirings are formed on the substrate 2 as shown in FIG. An interlayer insulating film and a planarizing film are formed.
Next, an ITO film is formed on the substrate 2 by vapor deposition or the like, and further patterned to form the pixel electrode 111.

Subsequently, an inorganic bank 112 a made of SiO ₂ is formed on the substrate 2 so as to surround the pixel electrode 111. Further, an organic bank 112b made of a resin is formed on the inorganic bank 112a, whereby an opening 112c is formed on the pixel electrode 111. In addition,
Examples of the material used for the organic bank 112b include polyimide and acrylic resin. As these materials, a material containing a fluorine element in advance may be used.
Next, the wettability on the substrate 2 is controlled by performing a continuous process of oxygen plasma-CF4 plasma on the opening 112c surrounded by the inorganic bank 112a and the organic bank 112b.

Thereafter, a liquid material containing a material for forming the hole injection layer is selectively disposed in the opening 112c by a droplet discharge method such as an ink jet method, and the hole injection / transport layer 151 (151R, 1R, 1
51G, 151B) and then this hole injection / transport layer 151 (151R, 151G)
151B) is insolubilized. Then, the formed hole injection / transport layer 151 (
151R, 151G, 151B) on the light emitting layer 150 (150R, 15B) by a droplet discharge method.
0G, 150B) is formed.
These hole injection / transport layer 151 (151R, 151G, 151B) and light emitting layer 150 (
150R, 150G, and 150B) are formed in a different order depending on the insolubilization method.

(Insolubilization treatment by heating)
As in the first embodiment, when the hole injection / transport layer 151 (151R, 151G, 151B) is insolubilized under different conditions by heat treatment using a hot plate or the like, for example, each color of R, G, and B is used. In order to adjust different deterioration characteristics, the hole injection / transport layer 151B corresponding to the blue light-emitting layer 150B is insolubilized under the first condition (first heating condition), and corresponds to the red and green light-emitting layers 150R and 150G. The hole injecting / transporting layers 151R and 151G are subjected to the second condition (second
In the case of insolubilization under heating conditions), first, after applying a liquid droplet containing a hole injection / transport layer forming material and a cross-linking agent to the pixel region corresponding to blue, insolubilization treatment under the first heating condition is performed. To form a hole injection / transport layer 151B. Accordingly, the insolubilized layer cross-linked according to the first heating condition and the hole injection / transport layer 151B in which a part remains as the pre-hole injection / transport layer.
Is formed.

Next, liquid droplets containing the light emitting layer forming material are applied onto the hole injection / transport layer 151B, and a baking process is performed to evaporate the solvent. Thereby, the hole injection / transport layer 151B
A part of the pre-hole injecting / transporting layer is eluted and mixed, and the light emitting layer 150B having the hole transporting property corresponding to the first heating condition is formed.

Subsequently, as in the case of blue, after applying a liquid droplet containing a hole injection / transport layer forming material and a cross-linking agent to the pixel regions corresponding to red and green, insolubilization treatment under the second heating condition is performed. Then, hole injection / transport layers 151R and 151G are formed, respectively. As a result, the insolubilized layer crosslinked according to the second heating condition and the hole injection / transport layers 151R and 151G in which a part remains as the pre-hole injection / transport layer are formed.
Next, liquid droplets containing a light emitting layer forming material are applied on the hole injection / transport layers 151R and 151G, respectively, and a baking process is performed to evaporate the solvent. Thereby, some of the pre-hole injection / transport layers of the hole injection / transport layers 151R and 151G are eluted and mixed, and the light-emitting layers 150R and 150G having hole transport properties corresponding to the second heating condition are respectively provided. A film is formed.

In this way, insolubilization processing is performed on the substrate 2 in a lump, and in the case of heat treatment in which insolubilization processing under individual conditions is difficult, hole injection /
After forming the transport layer and the light-emitting layer, pixels (light-emitting layers) having different hole transport properties can be formed by forming the hole injection / transport layer and the light-emitting layer in other pixel regions.

(Insolubilization with energy light)
For example, when the hole injection / transport layer is insolubilized by irradiating energy light such as ultraviolet light, electron beam, plasma light, etc., by using a mask corresponding to the pixel region to be insolubilized, The hole injecting / transporting layer 151 can be insolubilized under certain conditions.
(151R, 151G, 151B) is formed all at once.
Next, for example, using the mask in which the pixel region corresponding to blue is opened, the irradiation process of the energy light is performed on the hole injection / transport layer 151B under the first irradiation condition (for example, the irradiation time is long). Subsequently, the irradiation process of the energy light is performed on the hole injection / transport layers 151R and 151G under a second irradiation condition (for example, a short irradiation time) using a mask in which pixel regions corresponding to red and green are opened. Apply.

Thereby, the insolubilized layer cross-linked according to the first irradiation condition and the second irradiation condition and the hole injection / transport layers 151R, 151G, 151B in which a part remains as the pre-hole injection / transport layer are formed.
Next, liquid droplets containing the light emitting layer forming material are applied on the hole injection / transport layers 151R, 151G, and 151B, respectively, and a baking process is performed to evaporate the solvent. Thereby, some of the pre-hole injection / transport layers of the hole injection / transport layers 151R, 151G, and 151B are eluted and mixed, and have a hole transport property corresponding to the first irradiation condition and the second irradiation condition. Light emitting layer 15
0R, 150G, and 150B are deposited.

Thus, in the case of insolubilization treatment by irradiation with energy light, by using a mask, the hole injection / transport layers 151R, 151G, and 151B can be collectively formed, and the productivity is improved. Can contribute.
In the present embodiment, the insolubilization treatment conditions are adjusted in the hole injection / transport layer 151 (151R, 151G, 151B) according to each light emission characteristic even for the organic EL device 100 having a plurality of light emission characteristics. As a result, it becomes possible to control the hole transport characteristics by varying the insolubilized state, and the carrier balance among the plurality of light emitting layers can be easily maintained.

(Electronics)
Next, specific examples of electronic devices to which the organic EL device of the present invention can be applied will be described with reference to FIG. FIG. 7A is a perspective view showing an example in which the organic EL device is applied to a display unit of a portable personal computer (so-called notebook personal computer) 300. As shown in the figure, a personal computer (electronic device) 300 includes a main body 302 having a keyboard 301 and a display unit (display device) 303 to which an organic EL device is applied.

FIG. 7B is a perspective view showing an example in which an organic EL element is applied to a display unit of a mobile phone (electronic device) 400. As shown in the figure, the cellular phone 400 includes a plurality of operation buttons 401, a receiving part 402, a mouthpiece 403, and a display unit (display device) 404 to which an organic EL device is applied.
Since the electronic apparatus of the present embodiment includes the above-described organic EL device, the light emission characteristics are balanced between the pixels, high-quality display characteristics are obtained, and productivity is high, which contributes to reduction in manufacturing costs. Display devices and electronic devices that can be obtained can be obtained.

The organic EL element according to the light-emitting device of the present invention includes, in addition to the above-described mobile phone and laptop computer, a portable information device called PDA (Personal Digital Assistants), a personal computer, a workstation, a digital still camera, an in-vehicle monitor, Widely applied to electronic devices such as digital video cameras, TVs, viewfinder type, monitor direct-view type video tape recorders, car navigation devices, pagers, electronic notebooks, calculators, word processors, workstations, video phones, and POS terminals. Can do.

As described above, the preferred embodiments according to the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the spirit of the present invention.

For example, in the above embodiment, the organic layer is composed of a hole injection / transport layer and a light emitting layer. However, the present invention is not limited to this, and the hole injection layer and the hole transport layer are provided separately. It may be a configuration. Further, an electron transport layer may be provided between the light emitting layer and the cathode. The electron transport layer plays a role of injecting electrons into the light emitting layer. Materials for forming the electron transport layer include oxadiazole derivatives, anthraquinodimethane and its derivatives, benzoquinone and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, tetracyanoanthraquinodimethane and its derivatives, fluorenone derivatives , Diphenyldicyanoethylene and derivatives thereof, diphenoquinone derivatives, metal complexes of 8-hydroxyquinoline and derivatives thereof, and the like can be used.

Further, in the above embodiment, the hole injection / transport layer is subjected to insolubilization treatment, and the remaining hole injection / transport
The transport layer forming material is eluted into the light emitting layer, but the present invention is not limited to this. For example, the organic layer located in the lower layer of adjacent organic layers is insolubilized, and the remaining organic layer forming material is used as the upper layer. Carrier elution can be adjusted by elution in the organic layer located. For example, in the case where the organic layer has a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer, an insolubilizing treatment is applied to the lower organic layer among adjacent layers, and the organic layer forming material is It may be eluted in the upper organic layer.
In such a configuration, it becomes possible to control not only the hole transport property but also the electron transport property,
Carrier balance can be easily maintained.

It is principal part sectional drawing of the organic electroluminescent apparatus which concerns on this invention. It is explanatory drawing which shows one manufacturing process of an organic EL element. It is explanatory drawing which shows one manufacturing process of an organic EL element. It is a figure which shows the relationship between a crosslinking reaction temperature and an insolubilization rate. It is a figure which shows the relationship between a crosslinking reaction temperature and a current density. It is the figure which expanded the cross-section of the display area in an organic electroluminescent apparatus. It is a perspective view which shows an example of an electronic device.

Explanation of symbols

100: Organic EL element (organic EL device), 103, 151, 151R, 151G, 1
51B: hole injection / transport layer (first organic layer), 104: light emitting layer (second organic layer), 110
... Organic layer, 150, 150R, 150G, 150B ... Light emitting layer, 300 ... Personal computer (electronic device), 303, 404 ... Display unit (display device), 400 ... Mobile phone (electronic device)

Claims (15)

A method for producing an organic EL device in which a light emitting layer emits light by carriers transported through an organic layer,
Forming a first organic layer by a liquid phase method;
Applying insolubilization to the first organic layer;
Forming a second organic layer by a liquid phase method on the insolubilized first organic layer,
A method for manufacturing an organic EL device, comprising adjusting conditions for insolubilization of the first organic layer based on transport characteristics of the carrier in the second organic layer. In the manufacturing method of the organic electroluminescent apparatus of Claim 1,
A method for manufacturing an organic EL device, characterized in that the insolubilizing treatment conditions are made different among a plurality of the light emitting layers having different light emitting characteristics. In the manufacturing method of the organic electroluminescent apparatus of Claim 2,
After forming the first organic layer corresponding to the light emitting layer having the first light emitting characteristics and performing the insolubilization treatment, forming the first organic layer corresponding to the light emitting layer having the second light emitting characteristics. Then, the insolubilization treatment is performed, and a method for manufacturing an organic EL device is provided. In the manufacturing method of the organic electroluminescent apparatus of Claim 3,
The method for manufacturing an organic EL device, wherein the insolubilization treatment includes a heat treatment. In the manufacturing method of the organic electroluminescent apparatus of Claim 3 or 4,
A method of manufacturing an organic EL device, wherein the first organic layer is formed by a droplet discharge method. In the manufacturing method of the organic electroluminescent apparatus of Claim 2,
After the first organic layer corresponding to the light emitting layer having the first light emitting characteristics and the first organic layer corresponding to the light emitting layer having the second light emitting characteristics are collectively formed, the different insolubilization treatment conditions The method of manufacturing an organic EL device, wherein the insolubilization treatment is performed on each of the first organic layers. In the manufacturing method of the organic electroluminescent apparatus of Claim 6,
The insolubilization process includes an energy light irradiation process. In the manufacturing method of the organic electroluminescent apparatus in any one of Claim 1 to 7,
The method for manufacturing an organic EL device, wherein the insolubilization process includes a process of causing cross-linking between molecules of the material constituting the first organic layer. In the manufacturing method of the organic electroluminescent apparatus in any one of Claim 1 to 8,
Either one of the first organic layer or the second organic layer is the light emitting layer. An organic EL device in which a light emitting layer emits light by carriers transported through an organic layer,
A first organic layer formed by a liquid phase method;
A second organic layer formed on the first organic layer by the liquid phase method,
The second organic layer is formed based on the carrier transport property in the second organic layer.
An organic EL device comprising a mixed organic layer in which an organic layer forming material and a second organic layer forming material are mixed. The organic EL device according to claim 10,
The mixed organic layer has an insolubilized state of the first organic layer with respect to the second organic layer, and is mixed with the first organic layer forming material and the second organic layer forming material. apparatus. The organic EL device according to claim 11,
2. The organic EL device according to claim 1, wherein the insolubilized state is different between the plurality of light emitting layers having different light emission characteristics. The organic EL device according to any one of claims 10 to 12,
Either one of the first organic layer or the second organic layer is the light emitting layer. A display device comprising the organic EL device according to claim 10. An electronic apparatus comprising the display device according to claim 14.

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