JP2002289352A - Luminescence equipment and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide luminescence equipment and an electrical apparatus having low power consumption and long life. SOLUTION: In an organic compound film 203b, a domain 204b, in which concentration of a first organic compound 201 and concentration of a second organic compound 202 are changing gradually, is prepared. In addition, by forming a structure, where a domain 201b, which the first organic compound can develop its function, and a domain 202b, which the second organic compound can develop its function, exist, the functions of each materials can be developed. By this technique, an organic light emitting element of low power consumption and long life is provided, and the luminescence equipment and the electrical apparatus are produced using the above organic light emitting element.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an organic light-emitting device having an anode, a cathode, and a film containing an organic compound capable of emitting light by applying an electric field (hereinafter referred to as "organic compound film"). Light emitting device. In particular, the present invention relates to a light-emitting device using an organic light-emitting element in which an organic compound film contains a polymer compound, has a lower driving voltage than a conventional one, and has a longer element life, and a method for manufacturing the same. Note that a light-emitting device in this specification refers to an image display device or a light-emitting device using an organic light-emitting element as a light-emitting element. Also, a connector such as an anisotropic conductive film (FPC: Flexible printed circuit) or TAB (Tape Automated Bonding) tape or TCP is connected to the organic light emitting device.
(Tape Carrier Package), a module with a printed wiring board at the end of TAB tape or TCP, or COG (Chip OnGlass)
s) All modules in which an IC (integrated circuit) is directly mounted by the method are included in the light emitting device.

[0002]

2. Description of the Related Art An organic light-emitting device is a device that emits light when an electric field is applied. The light emission mechanism is such that by applying a voltage across the organic compound film between the electrodes, the electrons injected from the cathode and the holes injected from the anode recombine at the luminescent center in the organic compound film and become excited. (Hereinafter, referred to as “molecular exciton”), and emits energy when the molecular exciton returns to the ground state to emit light.

[0003] The molecular exciton formed by the organic compound can be a singlet excited state or a triplet excited state, and the present specification includes a case where either excited state contributes to light emission. It shall be.

In such an organic light emitting device, usually,
The organic compound film is formed as a thin film having a thickness of less than 1 μm.
Further, since the organic light emitting element is a self-luminous element in which the organic compound film itself emits light, there is no need for a backlight as used in a conventional liquid crystal display.
Therefore, it is a great advantage that the organic light emitting device can be manufactured to be extremely thin and lightweight.

In addition, in an organic compound film of, for example, about 100 to 200 nm, the time from injection of carriers to recombination is about several tens of nanoseconds in consideration of the carrier mobility of the organic compound film. Even within the process from recombination to light emission, light emission occurs on the order of microseconds or less. Therefore, one of the features is that the response speed is extremely fast.

Further, since the organic light emitting device is a carrier injection type light emitting device, it can be driven by a DC voltage.
Noise is less likely to occur. Regarding the driving voltage, first, the thickness of the organic compound film is made a uniform ultra-thin film of about 100 nm.
By selecting an electrode material that reduces the carrier injection barrier to the organic compound film and introducing a heterostructure (two-layer structure), a sufficient luminance of 100 cd / m ^{2 at} 5.5 V was achieved (Reference) 1: CW Tang and SA Van
Slyke, "Organic electroluminescent diodes", Applied
Physics Letters, vol. 51, No. 12, 913-915 (198
7)).

Due to such characteristics as thin and light weight, high-speed response, and DC low voltage driving, organic light-emitting devices have been receiving attention as next-generation flat panel display devices. In addition, since it is a self-luminous type and has a wide viewing angle, it has relatively good visibility and is considered to be effective as an element used for a display screen of a portable device.

By the way, with respect to the structure of the organic light-emitting device shown in Document 1, first, as a method of reducing the carrier injection barrier, the work function is low and the relatively stable M
g: Ag alloy is used for the cathode to enhance the electron injection property. This makes it possible to inject a large amount of carriers into the organic compound film.

Further, as an organic compound film, a single heterostructure in which a hole transport layer composed of a diamine compound and an electron transporting light emitting layer composed of tris (8-quinolinolato) aluminum (hereinafter, referred to as “Alq ₃ ”) are laminated. By applying the structure, the recombination efficiency of carriers is dramatically improved. This is explained as follows.

[0010] For example, in the case of the organic light emitting device having only Alq ₃ monolayers, since Alq ₃ is an electron-transporting property, most of electrons injected from the cathode reach the anode without recombining with holes As a result, the efficiency of light emission is extremely poor. That is, in order to make a single-layer organic light-emitting element emit light efficiently (or to be driven at a low voltage), a material capable of transporting both electrons and holes in a well-balanced manner (hereinafter, a “bipolar material”)
And Alq ₃ does not satisfy the condition.

However, if a single heterostructure as described in Document 1 is applied, electrons injected from the cathode are blocked at the interface between the hole transporting layer and the electron transporting light emitting layer, and are injected into the electron transporting light emitting layer. You are trapped. Therefore, the recombination of carriers is efficiently performed in the electron-transporting light-emitting layer, resulting in efficient light emission.

If the concept of such a carrier blocking function is developed, it becomes possible to control the recombination region of the carrier. As an example, by inserting a layer capable of blocking holes (hole blocking layer) between the hole transport layer and the electron transport layer, the holes are confined in the hole transport layer, and There is a report that succeeded in making the light emission. (Reference 2: Yasunori KIJIMA, Nobutoshi ASA
I and Shin-ichiro TAMURA, "A Blue Organic Light Em
itting Diode ", Japanese Journal of AppliedPhysics,
Vol. 38, 5274-5277 (1999)).

In addition, the organic light-emitting device described in Document 1 can be said to be an idea of functional separation in which the hole transport is performed by the hole transport layer, and the electron transport and light emission are performed by the electron transportable light-emitting layer. This concept of functional separation has further evolved into the concept of a double hetero structure (three-layer structure) in which a light emitting layer is sandwiched between a hole transport layer and an electron transport layer (Reference 3: Ch.
ihaya ADACHI, Shizuo TOKITO, Tetsuo TSUTSUI and Sh
ogo SAITO, "Electroluminescence in Organic Films w
ith Three-Layered Structure ", Japanese Journal of
Applied Physics, Vol. 27, No. 2, L269-L271 (198
8)).

The advantage of such function separation is that the function separation eliminates the need to simultaneously provide various functions (e.g., light-emitting properties, carrier transport properties, and carrier injection properties from an electrode) to one kind of organic material. That is, a wide degree of freedom can be given to molecular design and the like (for example, it is not necessary to forcibly search for a bipolar material). That is, high luminous efficiency can be easily achieved by combining materials having good light emitting characteristics, materials having excellent carrier transportability, and the like.

Due to these advantages, the concept of the laminated structure (carrier blocking function or function separation) itself described in Document 1 has been widely used up to the present.

[0016]

However, since the above-described laminated structure is a joint between different kinds of materials,
An energy barrier always occurs at the interface.
If the energy barrier exists, the movement of carriers at the interface is hindered, and thus the following two problems are raised.

First, it is an obstacle to further reduction of the driving voltage. In fact, in the current organic light-emitting devices, the device having a single-layer structure using a conjugated polymer is superior in terms of drive voltage, and the top data in power efficiency (unit: [lm / W]) (however, singlet (Comparison of light emission from excited state) is reported (Reference 4: Tetsuo Tsutsui, "Journal of the Society of Applied Physics, Society of Organic Molecules and Bioelectronics", Vol. 11, No. 1, P.8)
(2000)).

The conjugated polymer described in Reference 4 is a bipolar material, and can achieve the same level of carrier recombination efficiency as the laminated structure. Therefore, if the recombination efficiency of carriers can be made equivalent without using a laminated structure by a method such as using a bipolar material, it is shown that a single-layer structure with fewer interfaces actually lowers the driving voltage. I have.

For example, at the interface with the electrode, there is a method in which a material for relaxing the energy barrier is inserted to increase the carrier injecting property to reduce the driving voltage (Reference 5: Ta).
keoWakimoto, Yoshinori Fukuda, Kenichi Nagayama, A
kira Yokoi, Hitoshi Nakada, and Masami Tsuchida, "
Organic EL Cells Using Alkaline Metal Compoundsas
Electron Injection Materials ", IEEE TRANSACTIONS O
N ELECTRON DEVICES, VOL. 44, NO.8, 1245-1248 (199
7)). In Literature 5, the drive voltage was successfully reduced by using Li ₂ O as the electron injection layer.

However, between organic materials (for example, between the hole transport layer and the light emitting layer, hereinafter referred to as “organic interface”)
This is an unsolved field for carrier mobility, and is considered to be an important point for catching up with a low driving voltage of a single-layer structure.

Further, as another problem caused by the energy barrier, influence on the element life of the organic light emitting element is considered. That is, the movement of carriers is hindered, and the charge is accumulated, thereby lowering the luminance.

Although a clear theory has not been established for this degradation mechanism, a hole injection layer is inserted between the anode and the hole transport layer, and a rectangular wave ac drive is used instead of a dc drive. It has been reported that the decrease in luminance can be suppressed (Reference 6: SA VanSlyke, CH Ch.
en, and CW Tang, "Organic electroluminescentdev
ices with improved stability ", Applied Physics Let
ters, Vol. 69, No. 15, 2160-2162 (1996)). This can be said to be an experimental proof that the decrease in luminance was able to be suppressed by eliminating charge accumulation by inserting the hole injection layer and ac driving.

As described above, while the laminated structure has the merit that the recombination efficiency of carriers can be easily increased and the selection range of materials can be widened from the viewpoint of function separation, it is necessary to create a large number of organic interfaces. Thus, it can be said that the movement of the carrier is hindered and the driving voltage and the luminance are reduced.

Therefore, in the present invention, by manufacturing an element having a concept different from that of a conventionally used laminated structure, the energy barrier existing in the organic compound film is relaxed to increase the mobility of carriers, and at the same time, It is an object of the present invention to develop functions of various materials in the same manner as in the case of separating functions of a laminated structure (hereinafter, referred to as “function development”). Accordingly, it is an object of the present invention to provide an organic light emitting device having a lower driving voltage and a longer lifetime than the conventional device.

Another object of the present invention is to provide a light emitting device having a lower driving voltage and a longer life than the conventional one by using such an organic light emitting element. Furthermore, an object is to provide an electric appliance which consumes lower power and maintains a longer life than a conventional electric appliance by manufacturing an electric appliance using the light emitting device.

[0026]

As for the relaxation of the energy barrier in the laminated structure, the technique of inserting a carrier injection layer as shown in Reference 5 is remarkably observed. FIG. 1 illustrates an example using a hole injection layer and an energy band diagram.

In FIG. 1A, the anode 101 and the hole transport layer 102 are directly joined. In this case, the anode 101 and the hole transport layer 102 are joined.
Energy barrier 104 is large. However, HOMO located between the ionization potential of the anode and the highest occupied molecular orbital (hereinafter referred to as “HOMO”) level of the hole transport layer
By inserting a material having a level as the hole injection layer 103, the energy barrier can be designed in a stepwise manner (FIG. 1B).

By designing a step-like energy barrier as shown in FIG. 1B, it is possible to enhance the carrier injection property from the electrode and certainly reduce the drive voltage to some extent. However, the problem is that by increasing the number of layers, the number of organic interfaces increases conversely. This is considered to be the reason that the single-layer structure retains the top data of the driving voltage and the power efficiency as shown in Reference 4.

In other words, by overcoming this point, while taking advantage of the advantages of the laminated structure (a variety of materials can be combined and a complicated molecular design is not required),
In addition, it can catch up with the drive voltage and power efficiency of the single layer structure.

Therefore, the present inventor has found that in an organic compound film containing two or more (one or more of which are high molecular compounds) organic compounds, the interface in the organic compound film is substantially eliminated, and the energy barrier in the organic compound film is reduced. We devised a method to mitigate the problem.

That is, the organic compound film is formed of a hole injecting compound that receives holes from the anode, an electron injecting compound that receives electrons from the cathode, a hole transporting compound, an electron transporting compound, a hole or an electron. When containing at least two compounds selected from a group of a blocking compound capable of inhibiting movement, a luminescent compound emitting light, a region where the at least two compounds are mixed (hereinafter, referred to as
This is a method of substantially eliminating the interface in the organic compound film by providing a “mixed region”). Hereinafter, this method is referred to as mixed joining.

The reason why the polymer compound is used in the present invention is that the polymer compound generally has a higher carrier mobility and can be driven at a lower voltage. That is,
It is a feature of the present invention to carry out mixed joining in a system using a polymer compound.

In this case, the hole-injecting compound, the electron-injecting compound, the hole-transporting compound, and the electron-transporting compound may have a function of emitting light. Further, the light-emitting compound may have both carrier transporting property and carrier injecting property, or may be a material having poor carrier transporting property.

The mixed region is preferably formed at a position away from the anode and the cathode. For one reason,
This is because the barrier in the organic compound film is reduced by setting the interface in the organic compound film as a mixed region while maintaining a region capable of expressing functions such as carrier injection, carrier transport, and light emission.

In particular, when the mixed region has a light-emitting function, it is necessary to keep the mixed region away from the electrode and separate it from the electrode in order to prevent quenching (hereinafter, referred to as "quench") by the electrode. In that case, considering the diffusion of molecular excitons,
Preferably, the mixed region is separated from the electrode by at least 20 nm. The most effective distance may be selected in consideration of the carrier balance.

Incidentally, in the case of forming such a mixed junction, a method of doping a guest into the mixed region may be considered. In the mixed region, the movement of carriers is considered to be lubricating; therefore, it is preferable to use a light-emitting compound which emits light as a guest.

By performing the mixed bonding as described above, it is possible to show a clear laminated structure (ie,
There is no clear organic interface), and an organic light emitting device capable of exhibiting functions can be manufactured.

In the organic compound film containing a first organic compound and a second organic compound different from the first organic compound, the first organic compound and the second organic compound When a mixed region where an organic compound is mixed is provided, the first organic compound and the second organic compound may both be high molecular compounds, or one may be a low molecular compound. Further, a method of giving a continuous density change in the mixed region is more preferable. Hereinafter, these methods will be referred to as “continuous joining”. In addition, the mixed region in that case is particularly referred to as a “continuous joining region”.

FIG. 2 shows a conceptual diagram of a conventional laminated structure and the continuous joining of the present invention. FIG. 2A shows a conventional laminated structure (single heterostructure). That is, the first organic compound
Organic compound film 20 composed of 201 and second organic compound 202
3a, and a laminated structure formed from the first organic compound layer 201a and the second organic compound layer 202a (or
A clear organic interface). In this case, it is found that there is no region where the concentration of the first organic compound 201 and the concentration of the second organic compound 202 gradually change, and the region is discontinuous (that is, the concentration is 0 at the organic interface). % To 100%, or 100
% To 0%).

However, the continuous joining of the present invention (FIG. 2)
In the case of (b)), a region where the concentration of the first organic compound 201 and the concentration of the second organic compound 202 gradually change (that is, the continuous junction region 204b) exists in the organic compound film 203b. There is no clear organic interface. However, since a region where the first organic compound can exhibit a function (first functional region 201b) and a region where the second organic compound can exhibit a function (second functional region 202b) exist, the function of each material is expressed. it can.

By performing the continuous joining as described above, it is possible to show a clear laminated structure (ie,
There is no clear organic interface), and an organic light emitting device capable of exhibiting functions can be manufactured.

By the way, the first organic compound and the second organic compound have different functions from the viewpoint of the concept of the present invention (that is, the functions of various materials are exhibited without using a laminated structure). Is preferred.

In this case, if both the first organic compound and the second organic compound are high molecular compounds, it is considered that one emits light and the other expresses a carrier transport function. When the second organic compound is a low-molecular compound, the low-molecular compound emits light, the high-molecular compound exhibits a carrier transport function, and the high-molecular compound emits light. A configuration that exhibits a carrier transport function is conceivable.

Further, when the polymer compound exhibits a carrier transport function, the polymer compound is a polymer compound containing π electrons (that is, a conductive polymer compound), and the polymer compound is further subjected to chemical doping. It is preferable that the conductivity be improved by the application.

The polymer compound used as the hole transporting compound is preferably a polythiophene derivative, a polyaniline derivative, a polyvinyl carbazole derivative or the like, and the polymer compound used as the luminescent compound is a polyphenylene derivative, a polyparaphenylene derivative. Vinylene derivatives, polydialkylfluorene derivatives and the like are preferred.

When performing the above-described mixed bonding (including continuous bonding), there is a method of adding a third organic compound as a guest in the mixed region to impart the function of the guest. Conceivable. From the viewpoint of function development, it is preferable that a luminescent compound that emits light is used as a guest. This is because the first organic compound and the second organic compound that form the mixed region have a carrier transporting property or a blocking property, and the light emitting compound is added to the mixed region, so that the carrier recombination rate is reduced. To increase
This is because the luminous efficiency is considered to be high.

FIG. 3A is a conceptual diagram showing the concept. In FIG. 3A, on the substrate 301, between the anode 302 and the cathode 304,
An organic compound film 303 containing a first organic compound and a second organic compound was provided, and a compound 306 emitting light was added to the mixed region 305 to form a light emitting region.

In recent years, from the viewpoint of luminous efficiency,
An organic light-emitting element that can convert energy released when returning from a triplet excited state to a ground state (hereinafter, referred to as “triplet excited energy”) into light emission has been attracting attention because of its high luminous efficiency (Reference 7: DF O'Brien, MA Bal
do, ME Thompson and SR Forrest, "Improvedene
rgy transfer in electrophosphorescent devices ", Ap
plied Physics Letters, vol. 74, No. 3, 442-444 (19
99)) (Reference 8: Tetsuo TSUTSUI, Moon-Jae YANG, Masa
yuki YAHIRO, Kenji NAKAMURA, Teruichi WATANABE, Ta
ishi TSUJI, Yoshinori FUKUDA, Takeo WAKIMOTO and S
atoshi MIYAGUCHI, "High Quantum Efficiency in Orga
nic Light-Emitting Devices with Iridium-Complex as
a Triplet Emissive Center ", Japanese Journal of A
pplied Physics, Vol. 38, L1502-L1504 (1999)).

Reference 7 uses a metal complex containing platinum as a central metal, and Reference 8 uses a metal complex containing iridium as a central metal. An organic light-emitting element that can convert these triplet excitation energy into light emission (hereinafter, referred to as a “triplet light-emitting element”) can achieve higher luminance light emission and higher light emission efficiency than before.

However, according to the report example of Reference 8,
The half-life of luminance in the case where the initial luminance was set at 500 cd / m ² is 17
It is about 0 hours, and there is a problem in the element life. Therefore, by applying the present invention to a triplet light-emitting element, a very high-performance light-emitting element that has a long lifetime can be provided in addition to high-luminance light emission and high light emission efficiency due to light emission from a triplet excited state. .

Therefore, the present invention also includes a case where a material capable of converting triplet excitation energy into light emission is selected as the guest third organic compound and added to the mixed region.

The conceivable third organic compound is not limited to a luminescent compound that emits light. In particular, when the first organic compound or the second organic compound emits light, the third organic compound has the highest occupied molecular orbital as compared with the first organic compound and the second organic compound. It is preferable to use a compound having a large energy difference between (HOMO) and the lowest unoccupied molecular orbital (LUMO) (that is, a compound capable of blocking carriers and molecular excitons). According to this method, the recombination rate of carriers can be increased in the mixed region formed by the first organic compound and the second organic compound, and the luminous efficiency can be increased.

FIG. 3 (b) shows a conceptual diagram of this. In FIG. 3B, between the anode 302 and the cathode 304 on the substrate 301,
An organic compound film 303 containing a first organic compound and a second organic compound was provided, and a compound (blocking compound) 307 capable of blocking carriers and molecular excitons was added to a concentration change region 305 thereof.

In FIG. 3B, the mixed area 305 is
Further, a light-emitting region to which a light-emitting compound 306 which emits light is added is provided. That is, a method using a light-emitting compound that emits light as the third organic compound (FIG. 3A),
This is a mode in which the addition of a blocking compound is combined.
Here, since the compound 307 capable of blocking carriers and molecular excitons is closer to the cathode than the luminescent compound 306 that emits light, the compound 307 capable of blocking carriers and molecular excitons has a hole-blocking property. I just need.

Examples of the compound capable of blocking the carrier and the molecular exciton include a phenanthroline derivative, an oxadiazole derivative, and a triazole derivative.

By the way, when specifying the mixed region as described above, elemental analysis by SIMS is considered to be an important technique. In particular, in the case of continuous bonding, as can be seen from the conceptual diagram shown in FIG. 2, a remarkable difference is considered to appear as compared with the conventional laminated structure.

Therefore, of the elements constituting the first organic compound or the second organic compound, the detected amount of the element which can be detected by SIMS continuously changes in the direction from the anode to the cathode. The present invention includes a light emitting device having a light emitting region.

Further, a polymer compound containing a Group 15 element or a Group 16 element is generally often used for an organic light emitting device, and a compound containing a Group 17 element is used for improving the conductivity of the polymer compound. May be chemically doped. Therefore, by forming a continuous junction region from a material containing a Group 15 element to a Group 17 element and a material not containing the element, a change in concentration can be observed more remarkably. As the Group 15 to Group 17 elements, nitrogen,
The mainstream is phosphorus, oxygen, sulfur, fluorine, chlorine, bromine, iodine and the like.

Further, when a third organic compound is added as a guest to the mixed region, a metal complex may be used as the guest compound, in particular, a luminescent compound that emits light.

Therefore, the third organic compound is a metal complex having a metal element, and the detection region of the metal element which can be detected by SIMS is a region containing both the first organic compound and the second organic compound. Light emitting devices that are (ie, mixed regions) are also included in the present invention. As the metal element, aluminum, zinc, or beryllium is mainly used. When the third organic compound is a light-emitting compound that emits light from a triplet excited state, iridium or platinum can be detected because a metal complex having iridium or platinum as a central metal is mainly used.

By implementing the present invention as described above, it is possible to provide a light emitting device having a lower driving voltage and a longer life than the conventional one. Furthermore, by manufacturing an electric appliance using the light-emitting device, an electric appliance that consumes lower power than conventional ones and can be maintained for a long time can be provided.

[0062]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described. Note that the organic light-emitting element has at least one of an anode and a cathode that is transparent in order to extract light emission.In this embodiment, a transparent anode is formed over a substrate, and an element structure that extracts light from the anode is used. Describe.
Actually, a structure for extracting light from the cathode and a structure for extracting light from the side opposite to the substrate are also applicable to the present invention.

In practicing the present invention, a manufacturing process for forming a mixed region or a continuous junction region becomes important. The present inventor has proposed an organic compound film containing a polymer compound,
A process for forming a mixed region or a continuous bonding region has been devised. Therefore, a method for manufacturing the organic light emitting device disclosed in the present invention will be described here.

In a conventional process (when a laminated structure is formed by wet coating), for example, a first solution in which a first organic compound is dissolved is applied, and the solvent contained in the first solution is heated and the like. After complete removal, the second organic compound dissolved in a solution in which the first organic compound does not elute is deposited, so that a clear organic interface is generated.

For example, polystyrene sulfonic acid (hereinafter, referred to as polystyrene sulfonic acid)
An aqueous solution of polyethylene dioxythiophene (hereinafter referred to as “PEDOT”) doped with “PSS” was formed by spin coating, and heat-treated at 100 ° C. or higher under atmospheric pressure to completely remove water. Thereafter, polyparaphenylene vinylene having an alkoxyl group (hereinafter referred to as “PP
V)), a cross-sectional TEM image of the organic compound film formed by spin-coating a toluene solution of
The photograph is shown in FIG. As is clear from FIG. 4, the conventional process results in a laminated structure that produces a clear organic interface.

The present inventor has devised five manufacturing methods to solve this problem and to form a mixed region or a concentration change region. The embodiment will be described below with reference to the simplest case of an organic compound film containing two kinds of organic compounds.

FIG. 5 shows the first manufacturing method. First, a first solution 503a in which a first organic compound (polymer compound) is dissolved is wet-coated on a substrate 501 (FIG. 5 (a)) provided with an electrode 502 (FIG. 5 (b)). Next, as a step 511 for forming a mixed region or a continuous bonding region, the first solution is heated at a temperature at which the vapor pressure of the solvent contained in the first solution becomes lower than the atmospheric pressure of the working atmosphere (FIG. 5C). In a state 503b in which the solvent contained in the solution remains, the second solution 504 in which the second organic compound is dissolved is wet-coated (FIG. 5D). Finally, heating 512
Removes all the solvent to obtain an organic compound film of the present invention having a mixed region or a continuous junction region 505.

Next, a second manufacturing method is shown in FIG. First, a first solution 603a in which a first organic compound (polymer compound) is dissolved is wet-coated on a substrate 601 provided with an electrode 602 (FIG. 6A). Next, the first solution 603a is heated 611.
Is completely removed to form a first organic compound film 603b (FIG. 6B). Further, as a step 612 for forming a mixed region or a continuous bonding region, the elution region 603c is formed by placing the solvent contained in the first solution in the working atmosphere (FIG. 6 (c)). The second solution 604 in which the two organic compounds are dissolved is wet-coated (FIG. 6D). Finally, the solvent is completely removed by heating 613 to obtain an organic compound film of the present invention having a mixed region or a continuous bonding region 605.

Further, as a third manufacturing method, a mixed region or a continuous junction region can be formed by using a low molecular compound capable of forming a dry film as the first organic compound. That is, the first organic compound film 603b is formed by a vacuum evaporation method or the like.
After forming a film (that is, the state shown in FIG. 6B), a second organic compound (polymer compound) dissolved in a solvent capable of slightly dissolving the first organic compound is wet-coated, and FIG. ).

In the fourth production method, a low molecular weight compound can be used as the first organic compound in FIG. That is, first, the first organic compound film 603b is formed by a vacuum deposition method or the like to form the state shown in FIG. 6B, and is placed in a state where a solvent capable of dissolving the first organic compound is included in the working atmosphere. Then, the elution region 603c is formed (FIG. 6C).

By the way, all of the above-mentioned first to fourth production methods are composed of a polymer material to which the second organic compound is wet-coated. Conversely, as a fifth manufacturing method, a polymer material is first wet-coated as a first organic compound, a low-molecular compound is vacuum-deposited as a second organic compound, and then a mixed region or a continuous bonding region is formed. The present inventor has also devised a method of forming.

The fifth method is that a solution having a first organic compound (polymer compound) dissolved therein is wet-coated on a substrate having electrodes, and then the solution is transported into a vacuum chamber. In this method, a second organic compound (low-molecular compound) is diffused by forming a film of (low-molecular compound) by vacuum deposition and then heated to form a mixed region or a concentration-change region. The heating temperature may be a temperature at which the solvent in which the first organic compound is dissolved can be completely removed.

In the fifth method, a method in which heating is performed under reduced pressure of 10 ^-4 Pascal is more preferable. In this case, the heating temperature is preferably about 60C to 100C.

With respect to the wet coating method as described above, various methods are possible. In addition to the commonly used wet film forming method such as spin coating and dip coating, an alternate adsorption method and an ink jet method are conceivable. In particular, the inkjet method can pattern an organic compound with high precision and can also pattern over a wide range, so it is an effective method for creating a high-definition, large-area light-emitting device. Is believed to be.

FIG. 7 is a conceptual diagram for realizing the first manufacturing method by an ink jet method. First, the electrode 702
A bank structure 706 is formed by photolithography on a substrate 701 (FIG. 7A) having (FIG. 7B). Next, the first solution 703a in which the first organic compound (polymer compound) is dissolved is wet-coated by the inkjet printer head 721a (FIG. 7C). Further, as a step 711 for forming a mixed region or a continuous bonding region, the first solution 7
Heating is performed at a temperature lower than the temperature at which the vapor pressure of the solvent contained in 03a becomes the atmospheric pressure of the working atmosphere (FIG. 7 (d)), and in the state 703b in which the solvent contained in the first solution remains, The second solution 704 in which the organic compound is dissolved is wet-coated by the inkjet printer head 721b (FIG. 7E). Finally, all the solvent is removed by heating to obtain an organic compound film of the present invention having a mixed region or a continuous bonding region.

For example, when a compound that emits light is used as the second organic compound, each of the pixels 707a to 707c is separately coated with a compound that emits red, green, and blue using an ink jet printer head 721b. A full-color light-emitting device can be manufactured.

By the manufacturing method described above, the mixed region or the continuous junction region disclosed in the present invention can be formed.

[0078]

[Example 1] In this example, an organic light-emitting device manufactured by applying the method shown in FIG. 5 in the embodiment of the present invention will be specifically exemplified.

First, indium tin oxide (hereinafter, referred to as “ITO”) is sputtered on a glass substrate by 100 μm.
A film having a thickness of about nm is used as an anode. Next, an aqueous solution of PEDOT doped with PSS as a hole transporting material is formed on the anode by spin coating.

Here, as shown in FIG. 5, the substrate is heated at a temperature lower than the temperature at which the vapor pressure of water becomes atmospheric pressure (100 ° C.), and the water in the PEDOT aqueous solution is slightly left. And Further, an alkoxyl-substituted PPV using toluene as a solvent (hereinafter referred to as “MEH-PPV”) is formed by spin coating, and the solvent is completely removed by heating to 100 ° C. or more.

Finally, ytterbium is vacuum-deposited to a thickness of 400 nm as a cathode to obtain an organic light-emitting device of the present invention which emits green light derived from MEH-PPV.

Example 2 In this example, an organic light-emitting element manufactured by applying the method shown in FIG. 6 in the embodiment of the present invention will be specifically exemplified.

First, an ITO film is formed on a glass substrate 601 to a thickness of about 100 nm by sputtering to form an anode 602. next,
An aqueous solution of PEDOT doped with PSS as a hole transporting material is formed on the anode by spin coating,
The solvent (water) is completely removed by heating at 150 ° C. for 10 minutes.

Here, as shown in FIG. 6, in an atmosphere containing water vapor, polydioctylfluorene (hereinafter referred to as “PDOF”) using xylene as a solvent is formed into a film by spin coating. To remove water and xylene completely.

Finally, as a cathode, calcium was evaporated to 100 nm by vacuum evaporation and then aluminum was evaporated to 150 nm by PDOF.
The organic light-emitting device of the present invention, which emits blue light derived from the above, is obtained.

[Embodiment 3] In this embodiment, a method of applying a polymer compound dissolved in a solvent in which a low molecular compound is slightly dissolved is applied after forming a film of a low molecular compound by vacuum evaporation. The organic light emitting device to be manufactured is specifically exemplified.

First, indium tin oxide (hereinafter, referred to as “ITO”) is sputtered on a glass substrate by sputtering.
A film having a thickness of about nm is used as an anode. Next, 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenyl-amino] -triphenylamine (hereinafter referred to as" MTDATA ") is used as a hole transporting material. A film is formed on the anode by vacuum evaporation.

Here, a solution in which a PPV precursor soluble in a polar solvent is dissolved in ethanol is formed by spin coating. Thereafter, by heating to 80 ° C. or more, the solvent is completely removed, and at the same time, the PPV is polymerized.

Lastly, ytterbium is vacuum-deposited to a thickness of 400 nm as a cathode to obtain an organic light-emitting device of the present invention which emits green light derived from PPV.

[Embodiment 4] In this embodiment, an organic light-emitting device manufactured by applying an ink-jet method will be specifically exemplified.

First, ITO 702 is formed on a glass substrate 701 to a thickness of about 100 nm by sputtering, and a bank structure 706 is formed by photolithography (FIG. 7).
(b)). Next, PSS was doped as a hole transporting material.
PEDOT aqueous solution 703a for inkjet printer head 721
A film is formed on the anode by a, and the solvent (water) is completely removed by heating at 150 ° C. for 10 minutes. The PEDOT 703a formed as described above is hardly soluble in water, and only slightly elutes.

Further, an ink using an aqueous solution 704 in which a water-soluble PPV precursor is dissolved is formed into a film by an ink jet printer head 721b, and then heated to 100 ° C. or more to completely remove water and xylene. I do.

Finally, calcium was deposited as a cathode by vacuum evaporation to 100 nm and then aluminum to 150 nm, and PPV was deposited.
The organic light-emitting device of the present invention, which emits green light derived from the above, is obtained.

[Embodiment 5] In this embodiment, a solution having a first organic compound (polymer compound) dissolved therein is wet-coated on a substrate having an electrode, and then transported into a vacuum chamber. The organic compound (low-molecular compound) is formed into a film by vacuum evaporation, and then heated to diffuse the second organic compound (low-molecular compound) to form a mixed region or a continuous junction region, thereby forming a mixed region. An example in which an organic light-emitting element in which a compound that emits light (here, a compound that emits light from a triplet excited state) is doped in a continuous junction region is specifically illustrated. At this time, the heating temperature may be a temperature at which the solvent in which the first organic compound is dissolved can be completely removed. Further, it is more preferable to perform the heating under a reduced pressure of about 10 ^-4 Pascal.

First, indium tin oxide (hereinafter referred to as “ITO”) is sputtered onto a glass substrate by sputtering.
A film having a thickness of about nm is used as an anode. Next, in order to use polyvinyl carbazole (hereinafter referred to as “PVK”) as a hole transporting material, a chloroform solution of PVK is formed by spin coating, and the solvent is removed by heating.
After that, since a solution using the same solvent (chloroform) is coated, it is desirable that this film formation be performed several times in order to increase the film thickness to some extent.

Next, a bis (2-phenylpyridine) -acetylacetonatoiridium (hereinafter, referred to as “Ir (ppy) ₂ (acac)”) complex, which is a triplet luminescent material, was added to a chloroform solution of PVK in an amount of 5 wt%. Prepare the added solution and form the film first
The film is formed on the PVK film by spin coating.

Here, without heating the substrate, tris (8-quinolinolato) aluminum (hereinafter referred to as “Alq ₃ ”) as an electron transporting material is vacuum-deposited under a reduced pressure of 10 ⁻³ pascal. Thereafter, by baking at 80 ° C. under a reduced pressure of 10 ⁻⁴ pascal, PVK and Alq
Area with Ir (ppy) ₂ (acac) as guest with ₃ as host (P
Ir (ppy) ₂ (acac) -doped region) can be formed in the mixed region of VK and Alq ₃ .

Finally, an Al: Li alloy is deposited as a cathode by vacuum evaporation to a thickness of 150 nm to obtain an organic light emitting device of the present invention which emits green light derived from Ir (ppy) ₂ (acac).

[Embodiment 6] In this embodiment, a light emitting device including the organic light emitting element disclosed in the present invention will be described. FIG. 8 is a sectional view of an active matrix light emitting device using the organic light emitting element of the present invention. Although a thin film transistor (hereinafter, referred to as “TFT”) is used here as an active element, a MOS transistor may be used.

A top gate type TFT (specifically, a planar type TFT) is exemplified as a TFT, but a bottom gate type TFT is used.
An FT (typically an inverted staggered TFT) can also be used.

In FIG. 8, reference numeral 801 denotes a substrate. Here, a substrate that transmits visible light is used. Specifically, a glass substrate, a quartz substrate, a crystallized glass substrate, or a plastic substrate (including a plastic film) may be used. Note that the substrate 801 includes an insulating film provided on the surface.

A pixel portion 811 and a driving circuit are provided on a substrate 801.
812 are provided. First, the pixel portion 811 will be described.

The pixel section 811 is an area for displaying an image.
There are a plurality of pixels on the substrate, and each pixel has a TFT (hereinafter referred to as “current control TFT”) 802 for controlling a current flowing through the organic light emitting element, a pixel electrode (anode) 803, and an organic compound film. 804 and a cathode 805 are provided. Although FIG. 8 shows only the current control TFT, a TFT for controlling the voltage applied to the gate of the current control TFT (hereinafter, referred to as “switching TFT”) is provided.

The current control TFT 802 is a p-channel type T
Preferably, FT is used. Although an n-channel TFT can be used, when a current control TFT is connected to the anode of the organic light emitting element as shown in FIG. 8, the p-channel TFT can reduce power consumption. However, switching
The TFT may be an n-channel TFT or a p-channel TFT.

The pixel electrode 803 is electrically connected to the drain of the current control TFT 802. In this embodiment, a conductive material having a work function of 4.5 to 5.5 eV is used as the material of the pixel electrode 803, and thus the pixel electrode 803 functions as an anode of the organic light emitting element. Typically, indium oxide, tin oxide, zinc oxide, or a compound thereof (ITO or the like) may be used for the pixel electrode 803. An organic compound layer 804 is provided over the pixel electrode 803.

Further, a cathode 805 is formed on the organic compound layer 804.
Is provided. As a material of the cathode 805, it is desirable to use a conductive material having a work function of 2.5 to 3.5 eV. As the cathode 805, a conductive film containing an alkali metal element or an alkali metal element, a conductive film containing aluminum, or a material in which aluminum, silver, or the like is stacked over the conductive film may be typically used.

The layer including the pixel electrode 803, the organic compound layer 804, and the cathode 805 is covered with a protective film 806.
The protective film 806 is provided to protect the organic light emitting device from oxygen and water. As a material of the protective film 806,
Silicon nitride, silicon nitride oxide, aluminum oxide, tantalum oxide, or carbon (specifically, diamond-like carbon) is used.

Next, the drive circuit 812 will be described. The driver circuit 812 is an area that controls the timing of signals (gate signals and data signals) transmitted to the pixel portion 811;
A shift register, a buffer, a latch, an analog switch (transfer gate), or a level shifter is provided. In FIG. 8, n is a basic unit of these circuits.
CMO consisting of channel TFT807 and p-channel TFT808
The S circuit is shown.

Note that the circuit configuration of the shift register, buffer, latch, analog switch (transfer gate) or level shifter may be a known one. Although the pixel portion 811 and the driver circuit 812 are provided over the same substrate in FIG. 8, an IC or an LSI can be electrically connected without providing the driver circuit 812.

Although the pixel electrode (anode) 803 is electrically connected to the current control TFT 802 in FIG. 8, a structure in which the cathode is connected to the current control TFT 802 may be employed. In that case, the pixel electrode may be formed using the same material as the cathode 805, and the cathode may be formed using the same material as the pixel electrode (anode) 803.
In that case, the current control TFT is preferably an n-channel TFT.

The light emitting device shown in FIG. 8 is manufactured in the process of forming the wiring 809 after forming the pixel electrode 803. In this case, the surface of the pixel electrode 803 may be roughened. There is. Since the organic light-emitting element is a current-driven element, the surface roughness of the pixel electrode 803 causes
It is also conceivable that the characteristics are deteriorated.

Therefore, as shown in FIG. 9, a light emitting device in which a pixel electrode 903 is formed after forming a wiring 909 is also conceivable. In this case, it is considered that the current injection property from the pixel electrode 903 is improved as compared with the structure of FIG.

In FIG. 8 and FIG. 9, the pixel portion 811 is formed by a bank 810 or 910 of a positive taper type.
Or each pixel installed in 911 is separated. By making the bank-like structure, for example, a reverse tapered type, a structure in which the bank-like structure does not contact the pixel electrode can be adopted. One example is shown in FIG.

In FIG. 10, a wiring and a separation unit 1010 which also functions as a separation unit using a wiring are provided. As shown in FIG. 10, the shape of the wiring and the isolation portion 1010 (structure with eaves) is such that a metal constituting the wiring and a material (for example, metal nitride) having a lower etch rate than the metal are stacked and etched. Can be formed. With this shape, a short circuit between the pixel electrode 1003 or the wiring and the cathode 1005 can be prevented. Note that in FIG. 10, unlike a normal active matrix light emitting device, a cathode 1005 on a pixel has a stripe shape (similar to a passive matrix cathode).

Here, FIG. 11 shows the appearance of the active matrix type light emitting device shown in FIG. FIG. 11 (a)
11 shows a top view, and FIG. 11B shows a cross-sectional view of FIG. 11A taken along the line PP ′. Also, reference is made to the reference numerals in FIG.

In FIG. 11A, reference numeral 1101 denotes a pixel portion;
Denotes a gate signal side driving circuit, and 1103 denotes a data signal side driving circuit. A signal transmitted to the gate signal side driver circuit 1102 and the data signal side driver circuit 1103 is input wiring 1104
Is input from a TAB (Tape Automated Bonding) tape 1105 via a. Although not shown, instead of the TAB tape 1105, a TCP (Ta) having an IC (integrated circuit) provided on the TAB tape is used.
pe Carrier Package).

At this time, reference numeral 1106 denotes a cover material provided above the organic light-emitting element shown in FIG. 9, and is adhered by a sealing material 1107 made of resin. As the cover material 1106, any material may be used as long as it does not transmit oxygen and water. In this embodiment, the cover material 1106 is formed as shown in FIG.
As shown in FIG. 7, a plastic material 1106a and carbon films (specifically, diamond-like carbon films) 1106b and 1106c provided on the front and back surfaces of the plastic material 1106a, respectively.
Consists of

Further, as shown in FIG. 11B, the sealing material 1107 is covered with a sealing material 1108 made of a resin, so that the organic light emitting element is completely sealed in the sealed space 1109.
The closed space 1109 may be filled with an inert gas (typically, nitrogen gas or a rare gas), a resin, or an inert liquid (eg, liquid fluorinated carbon typified by perfluoroalkane). Further, it is also effective to provide a moisture absorbent or a deoxidizer.

Further, a polarizing plate may be provided on the display surface (surface on which an image is observed) of the light emitting device shown in this embodiment. This polarizing plate has an effect of suppressing reflection of light incident from the outside and preventing an observer from being reflected on the display surface. Generally, a circularly polarizing plate is used. However, in order to prevent the light emitted from the organic compound layer from being reflected by the polarizing plate and returning to the inside, it is preferable to adjust the refractive index to have a structure with less internal reflection.

The organic light emitting device included in the light emitting device of this embodiment may be any of the organic light emitting devices disclosed in the present invention.

[Embodiment 7] In this embodiment, an active matrix type light emitting device will be described as an example of a light emitting device including an organic light emitting device disclosed in the present invention. 1 shows a light emitting device having a structure (hereinafter, referred to as “upward emission”) for extracting light from a side opposite to a substrate on which light is emitted. FIG. 19 shows a sectional view thereof.

Although a thin film transistor (hereinafter, referred to as “TFT”) is used here as an active element, a MOS transistor may be used. Also, as a TFT, a top gate TFT (specifically, a planar TFT) is exemplified.
A bottom gate type TFT (typically, an inverted stagger type TFT) can also be used.

In this embodiment, the substrate 1901, the current control TFT 1902 formed in the pixel portion, and the drive circuit 1912 may have the same configuration as in the sixth embodiment.

Although the first electrode 1903 is connected to the drain of the current control TFT 1902, it is preferable to use a conductive material having a higher work function because it is used as an anode in this embodiment. Typical examples thereof include metals such as nickel, palladium, tungsten, gold, and silver. In this embodiment, it is preferable that the first electrode 1903 does not transmit light, but in addition, it is more preferable to use a material having high light reflectivity.

On the first electrode 1903, an organic compound layer 1904 is provided. Further, a second electrode 1905 is provided on the organic compound layer 1904, and is used as a cathode in this embodiment. In that case, as the material of the second electrode 1905, it is desirable to use a conductive material having a work function of 2.5 to 3.5 eV. Typically, a conductive film containing an alkali metal element or an alkali metal element, a conductive film containing aluminum, or a stacked layer of aluminum or silver on the conductive film,
May be used. However, since the present embodiment emits light upward, it is a major premise that the second electrode 1905 is light-transmissive. Therefore, when these metals are used, it is preferable that the thickness be an ultrathin film of about 20 nm.

Further, the first electrode 1903, the organic compound layer 1904,
The layer including the second electrode 1905 is covered with a protective film 1906. The protective film 1906 is provided to protect the organic light emitting device from oxygen and water. In this embodiment, any material that transmits light may be used.

Although the first electrode (anode) 1903 is electrically connected to the current control TFT 1902 in FIG. 19, a structure in which the cathode is connected to the current control TFT 1902 may be employed. In that case, the first electrode may be formed of a cathode material, and the second electrode may be formed of an anode material. At this time, the current control TFT is n
It is preferable to use a channel type TFT.

Further, reference numeral 1907 denotes a cover material, which is adhered by a sealing material 1908 made of resin. Cover material 1907
Any material may be used as long as it is a material that does not transmit oxygen and water and that transmits light. In this embodiment, glass is used. The closed space 1909 may be filled with an inert gas (typically, nitrogen gas or a rare gas), a resin, or an inert liquid (eg, liquid fluorinated carbon typified by perfluoroalkane). Further, it is also effective to provide a moisture absorbent or a deoxidizer.

A signal transmitted to the gate signal side driving circuit and the data signal side driving circuit is input from a TAB (Tape Automated Bonding) tape 1914 via an input wiring 1913. Although not shown, instead of the TAB tape 1414, a TCP (Tape C) in which an IC (integrated circuit) is provided
arrier Package).

Further, a polarizing plate may be provided on the display surface (surface for observing an image) of the light emitting device shown in this embodiment. This polarizing plate has an effect of suppressing reflection of light incident from the outside and preventing an observer from being reflected on the display surface. Generally, a circularly polarizing plate is used. However, in order to prevent the light emitted from the organic compound layer from being reflected by the polarizing plate and returning to the inside, it is preferable to adjust the refractive index to have a structure with less internal reflection.

The organic light emitting device included in the light emitting device of this embodiment may be any of the organic light emitting devices disclosed in the present invention.

[Embodiment 8] In this embodiment, a passive matrix light emitting device will be described as an example of a light emitting device including the organic light emitting element disclosed in the present invention. FIG. 12A shows a top view thereof, and FIG. 12B shows a cross-sectional view of FIG. 12A taken along a line PP ′.

In FIG. 12A, reference numeral 1201 denotes a substrate;
Here, a plastic material is used. Plastic materials include polyimide, polyamide, acrylic resin, epoxy resin, PES (polyethersulfone), PC (polycarbonate), PET (polyethylene terephthalate) or PEN (polyethernitrile) in plate or film form. Can be used.

Reference numeral 1202 denotes a scanning line (anode) made of an oxide conductive film.
In this embodiment, an oxide conductive film in which gallium oxide is added to zinc oxide is used. Reference numeral 1203 denotes a data line (cathode) made of a metal film. In this embodiment, a bismuth film is used. Reference numeral 1204 denotes a bank made of an acrylic resin, which functions as a partition for dividing the data line 1203. A plurality of scanning lines 1202 and data lines 1203 are both formed in a stripe shape and provided to be orthogonal to each other. Although not shown in FIG. 12A, an organic compound layer is interposed between the scanning line 1202 and the data line 1203, and the intersection 1205 becomes a pixel.

The scanning line 1202 and the data line 1203 are
It is connected to an external drive circuit via a TAB tape 1207.
Note that reference numeral 1208 denotes a wiring group including the scanning lines 1202, and reference numeral 1209 denotes a wiring group including a set of connection wirings 1206 connected to the data lines 1203. Although not shown,
TCP with IC on TAB tape instead of TAB tape 1207
May be connected.

In FIG. 12B, reference numeral 1210 denotes a sealing material, and reference numeral 1211 denotes a cover material bonded to the plastic material 1201 by the sealing material 1210. As the sealant 1210, a light-curing resin may be used, and a material with little degassing and low hygroscopicity is preferable. As the cover material, the same material as the substrate 1201 is preferable, and glass (including quartz glass) or plastic can be used. Here, a plastic material is used.

Next, an enlarged view of the structure of the pixel region is shown in FIG.
This is shown in (c). 1213 is an organic compound layer. FIG.
As shown in (c), the width of the lower layer of the bank 1204 is smaller than the width of the upper layer, and the data line 1203 can be physically separated. A pixel portion 1214 surrounded by a sealing material 1210 is also provided.
Is shut off from outside air by a sealing material 1215 made of resin,
The structure prevents the organic compound layer from deteriorating.

In the light emitting device of the present invention having the above-described structure, the pixel portion 1214 includes the scanning line 1202, the data line 1203, the bank
Since it is formed using the organic compound layer 1204 and the organic compound layer 1213, it can be manufactured by a very simple process.

Further, a polarizing plate may be provided on the display surface (surface for observing an image) of the light emitting device shown in this embodiment. This polarizing plate has an effect of suppressing reflection of light incident from the outside and preventing an observer from being reflected on the display surface. Generally, a circularly polarizing plate is used. However, in order to prevent the light emitted from the organic compound layer from being reflected by the polarizing plate and returning to the inside, it is preferable to adjust the refractive index to have a structure with less internal reflection.

As the organic light emitting device included in the light emitting device of this embodiment, any of the organic light emitting devices disclosed in the present invention may be used.

[Embodiment 9] This embodiment shows an example in which a printed wiring board is provided in the light emitting device shown in Embodiment 8 to form a module.

The module shown in FIG.
(Here, the pixel portion 1302 and the wirings 1303a and 1303b are included)
A TAB tape 1304 is attached to the PWB, and a printed wiring board 1305 is attached via the TAB tape 1304.

Here, a functional block diagram of the printed wiring board 1305 is shown in FIG. At least I / O ports (input or output unit) 1306 inside the printed wiring board 1305,
1309, an IC functioning as the data signal side driving circuit 1307 and the gate signal side circuit 1308 are provided.

As described above, a module having a configuration in which the TAB tape is attached to the substrate having the pixel portion formed on the substrate surface, and the printed wiring plate having a function as a driving circuit is attached via the TAB tape, In the specification, the module will be referred to as a drive circuit external type module.

The organic light emitting device included in the light emitting device of this embodiment may be any of the organic light emitting devices disclosed in the present invention.

[Embodiment 10] In this embodiment, an example in which a printed wiring board is provided in the light emitting device shown in Embodiment 6, 7, or 8 to form a module will be described.

The module shown in FIG.
(Here, the pixel portion 1402, the data signal side driving circuit 1403,
The TAB tape 1405 is attached to the gate signal side drive circuit 1404 and the wirings 1403a and 1404a), and the TAB tape 14
A printed wiring board 1406 is attached via 05.
FIG. 14B is a functional block diagram of the printed wiring board 1406.

As shown in FIG. 14B, the printed wiring board 1
Inside the 406, at least an IC functioning as the I / O ports 1407 and 1410 and the control unit 1408 is provided. Although the memory unit 1409 is provided here, it is not always necessary. The control unit 1408 is a part having a function of controlling a drive circuit, correcting image data, and the like.

In this specification, a module having a structure in which a printed wiring board having a function as a controller is mounted on a substrate on which an organic light emitting element is formed is particularly referred to as an external module with a controller.

As the organic light emitting device included in the light emitting device of this embodiment, any of the organic light emitting devices disclosed in the present invention may be used.

[Embodiment 11] In this embodiment, an example of a light-emitting device in which the organic light-emitting element disclosed in the present invention is driven at a constant voltage by digital time gray scale display will be described.

FIG. 17A shows a circuit configuration of a pixel using an organic light emitting element. Tr represents a transistor, and Cs represents a storage capacitor. In the circuit configuration in FIG. 17A, the source line is connected to the source side of the transistor Tr1, and the gate line is connected to the gate of the transistor Tr1. The power supply line is connected to the storage capacitor Cs and transistor Tr.
2 is connected to the source side. Since the anode of the organic light emitting device of the present invention is connected to the drain side of the transistor Tr2, the opposite side of the transistor Tr2 across the organic light emitting device is a cathode.

In this circuit, when the gate line is selected, a current flows from the source line to Tr1, and a voltage corresponding to the signal is stored in Cs. Then, the current controlled by the voltage (V _gs ) between the gate and the source of Tr2 becomes Tr2
And the organic light-emitting element.

After Tr1 is selected, Tr1 is turned off and the voltage of Cs (V _gs ) is maintained. Therefore, V _gs
Can continue to flow as much as possible.

FIG. 17B shows a chart for driving such a circuit by digital time gray scale display. That is, one frame is divided into a plurality of subframes. In FIG. 17B, one frame is divided into six subframes (SF1 to SF6) with a 6-bit gradation. TA is the write time. In this case, the ratio of each sub-frame emission period is 32: 16: 8:
4: 2: 1.

FIG. 17C shows an outline of a TFT substrate drive circuit in this embodiment. In the substrate configuration shown in FIG. 17C, the pixel portion in which the organic light emitting device of the present invention is used for each pixel is shown in FIG.
The power supply line and the cathode as shown in FIG. 7 (a) are connected. The shift register is connected to the pixel section in the order of shift register → latch 1 → latch 2 → pixel section. A digital signal is input to latch 1 and latch 2
The image data can be sent to the pixel portion by the latch pulse inputted to the pixel section.

The gate driver and the source driver are provided on the same substrate, and the pixel circuit and the driver are designed to be driven digitally.
A uniform image can be obtained without being affected by variations in characteristics.

[Embodiment 12] This embodiment shows an example of an active matrix type constant current drive circuit which is driven by applying a constant current to the organic light emitting device disclosed in the present invention. FIG. 18 shows the circuit configuration.

A pixel 1810 shown in FIG.
i, a first scanning line Gj, a second scanning line Pj, and a power supply line Vi. The pixel 1810 includes Tr1, Tr2, T
r3, Tr4, a mixed junction type organic light emitting element 1811 and a storage capacitor 1812.

The gates of Tr3 and Tr4 are both connected to the first scanning line Gj. One of the source and the drain of Tr3 is connected to the signal line Si, and the other is connected to the source of Tr2. One of the source and the drain of Tr4 is connected to the source of Tr2, and the other is connected to the gate of Tr1. That is, one of the source and the drain of Tr3 is connected to one of the source and the drain of Tr4.

The source of Tr1 is connected to the power supply line Vi, and the drain is connected to the source of Tr2. The gate of Tr2 is connected to the second scanning line Pj. The drain of Tr2 is connected to the pixel electrode of the organic light emitting element 1811. The organic light emitting device 1811 has a pixel electrode, a counter electrode, and an organic light emitting layer provided between the pixel electrode and the counter electrode. A constant voltage is applied to the opposite electrode of the organic light emitting element 1811 by a power supply provided outside the light emitting panel.

Note that Tr3 and Tr4 are n-channel type T
Either FT or p-channel TFT may be used. However,
Tr3 and Tr4 have the same polarity. Tr1 is n
Either a channel TFT or a p-channel TFT may be used. Tr2 is composed of an n-channel TFT and a p-channel TF
Either T may be used. One of the pixel electrode and the counter electrode of the light emitting element is an anode, and the other is a cathode. Tr2 is p
In the case of a channel type TFT, an anode is used as a pixel electrode,
It is desirable to use a cathode as the counter electrode. Conversely, Tr
When 2 is an n-channel type TFT, it is desirable to use a cathode as a pixel electrode and an anode as a counter electrode.

The storage capacitor 1812 is formed between the gate and the source of Tr1. The storage capacity 1812 is Tr1
Although it is provided in order to more reliably maintain the voltage (V _GS ) between the gate and the source, it is not necessary to provide it.

In the pixel shown in FIG. 18, the current supplied to the signal line Si is controlled by a current source included in the signal line driving circuit.

By applying the above-described circuit configuration, it is possible to perform constant current driving in which a constant current is applied to the organic light emitting element to keep the luminance constant. The organic light-emitting device having the mixed region disclosed in the present invention has a longer life than the conventional organic light-emitting device. However, by performing the above-described constant current driving, the life can be further prolonged. It is.

[Embodiment 13] The light emitting device of the present invention described in the above embodiments has advantages of low power consumption and long life. Therefore, an electric appliance in which the light emitting device is included as a display unit or the like can operate with lower power consumption than the conventional one and can be maintained for a long time. In particular, an electric appliance such as a portable device using a battery as a power source is extremely useful because low power consumption is directly linked to convenience (the battery is hard to run out).

Since the light emitting device is of a self-luminous type, it does not require a backlight unlike a liquid crystal display device.
Since the thickness of the organic compound layer is less than 1 μm, the thickness and weight can be reduced. Therefore, an electric appliance including the light emitting device as a display unit or the like is a thinner and lighter electric appliance than before. This is also extremely useful, particularly for electric appliances such as portable devices, because it is directly connected to convenience (lightness and compactness when carrying). Furthermore, it is undoubted that the thinness (not bulky) of electric appliances in general is also useful from the viewpoint of transportation (mass transportation is possible) and installation (securing space such as rooms).

Since the light-emitting device is of a self-luminous type, it has excellent characteristics in a bright place and a wide viewing angle as compared with a liquid crystal display device. Therefore, an electric appliance having the light-emitting device as a display portion has a great advantage in viewability of display.

That is, the electric appliance using the light emitting device of the present invention has the advantages of the conventional organic light emitting element such as thin and light weight and high visibility, as well as the features of low power consumption and long life, and is extremely useful. It is.

[0170] In this embodiment, an electric appliance including the light emitting device of the present invention as a display portion will be described. Specific examples are shown in FIGS. 15 and 16. In addition, any of the elements disclosed in the present invention may be used as the organic light emitting element included in the electric appliance of this embodiment. The form of the light emitting device included in the electric appliance of this embodiment may be any of the forms shown in FIGS.

FIG. 15A shows a display using an organic light-emitting device, which includes a housing 1501a, a support 1502a, and a display unit 1503a.
including. By manufacturing a display using the light-emitting device of the present invention as the display portion 1503a, a display that is thin, lightweight, and long-lasting can be realized. Therefore, transportation becomes simple, space can be saved during installation, and the life is long.

FIG. 15B shows a video camera,
1b, display unit 1502b, voice input unit 1503b, operation switch 1504
b, battery 1505b, and image receiving unit 1506b. By manufacturing a video camera using the light-emitting device of the present invention as the display portion 1502b, a lightweight video camera with low power consumption can be realized. Therefore, battery consumption is reduced,
It is easy to carry.

FIG. 15C shows a digital camera,
501c, display unit 1502c, eyepiece unit 1503c, operation switch 1504c
including. By manufacturing a digital camera using the light-emitting device of the present invention as the display portion 1502c, a light-weight digital camera with low power consumption can be realized. Therefore, the consumption of the battery is reduced and the portability is simplified.

FIG. 15D shows an image reproducing apparatus provided with a recording medium, which includes a main body 1501d, a recording medium (CD, LD, or DVD) 1502d, operation switches 1503d, a display section (A) 1504d, and a display section ( B) Including 1505d. The display portion (A) 1504d mainly displays image information, and the display portion (B) 1505d mainly displays character information. The light-emitting device of the present invention is used for the display portion (A) 1504d and the display portion.
(B) By manufacturing the image reproducing device used as 1505d, the image reproducing device which consumes less power, is lightweight, and can be maintained for a long time can be realized. Note that the image reproducing device provided with the recording medium includes a CD reproducing device, a game machine, and the like.

FIG. 15E shows a portable (mobile) computer, which includes a main body 1501e, a display section 1502e, an image receiving section 1503e,
It includes an operation switch 1504e and a memory slot 1505e. By manufacturing a portable computer using the light-emitting device of the present invention as the display portion 1502e, a thin and lightweight portable computer with low power consumption can be realized. Therefore, the consumption of the battery is reduced and the portability is simplified. In addition,
This portable computer can record information on a recording medium in which a flash memory or a nonvolatile memory is integrated, and can reproduce the information.

FIG. 15F shows a personal computer, which includes a main body 1501f, a housing 1502f, a display portion 1503f, and a keyboard 1.
504f. By manufacturing a personal computer using the light-emitting device of the present invention as the display portion 1503f, a thin and lightweight personal computer with low power consumption can be realized. In particular, when a portable use such as a notebook computer is required, a great advantage is obtained in terms of battery consumption and lightness.

It is to be noted that the electric appliances often display information distributed through electronic communication lines such as the Internet or wireless communication such as radio waves, and in particular, opportunities to display moving image information are increasing. The response speed of the organic light-emitting element is very fast, which is suitable for such moving image display.

Next, FIG. 16A shows a mobile phone, and the main body 1
601a, audio output unit 1602a, audio input unit 1603a, display unit 1604
a, operation switch 1605a, and antenna 1606a. By manufacturing a mobile phone using the light-emitting device of the present invention as the display portion 1604a, a thin and lightweight mobile phone with low power consumption can be realized. Therefore, battery consumption is reduced,
It is easy to carry and compact.

FIG. 16B shows an audio device (specifically, audio for a vehicle), which includes a main body 1601b, a display portion 1602b, and operation switches 1603b and 1604b. Display unit of the light emitting device of the present invention
By manufacturing the audio device used as 1602b, a lightweight audio device with low power consumption can be realized. Also,
In this embodiment, the in-vehicle audio is shown as an example, but it may be used for home audio.

In the electric appliances shown in FIGS. 15 and 16, a light sensor is further built in and a means for detecting the brightness of the use environment is provided, so that the light emission luminance can be adjusted according to the brightness of the use environment. It is effective to have a function of modulating the frequency. If the user can secure a brightness of 100 to 150 in contrast ratio compared to the brightness of the usage environment,
Image or character information can be recognized without any problem. That is, when the use environment is bright, it is possible to increase the brightness of the image to make it easier to see, and when the use environment is dark, it is possible to suppress the brightness of the image and reduce power consumption.

Various electric appliances using the light emitting device of the present invention as a light source can be said to be very useful because they can operate with low power consumption and can be made thin and light. Typically,
An electric appliance including the light-emitting device of the present invention as a light source such as a backlight or a front light of a liquid crystal display device or a light source of a lighting device can realize low power consumption and can be thin and lightweight.

Therefore, even when the display portions of the electric appliances shown in FIGS. 15 and 16 shown in this embodiment are all liquid crystal displays, the light emitting device of the present invention is used as a backlight or front light of the liquid crystal display. By manufacturing the electric appliance, a thin and lightweight electric appliance with low power consumption can be achieved.

[0183]

According to the present invention, a light emitting device which consumes less power and has a long life can be obtained.
Further, by using such a light-emitting device for a light source or a display portion, it is possible to obtain an electric appliance which is bright, consumes little power, and is long-lasting.

[Brief description of the drawings]

FIG. 1 illustrates the role of a hole injection layer.

FIG. 2 is a diagram illustrating a configuration of an organic light-emitting element.

FIG. 3 is a diagram illustrating a configuration of an organic light-emitting element.

FIG. 4 is a diagram showing a cross-sectional TEM photograph of an organic compound film.

FIG. 5 illustrates a method for manufacturing an organic compound film.

FIG. 6 illustrates a method for manufacturing an organic compound film.

FIG. 7 illustrates a method for manufacturing an organic compound film.

FIG. 8 illustrates a cross-sectional structure of a light-emitting device.

FIG. 9 illustrates a cross-sectional structure of a light-emitting device.

FIG. 10 illustrates a cross-sectional structure of a light-emitting device.

FIG. 11 illustrates a top structure and a cross-sectional structure of a light-emitting device.

FIG. 12 illustrates a top structure and a cross-sectional structure of a light-emitting device.

FIG. 13 illustrates a structure of a light-emitting device.

FIG. 14 illustrates a structure of a light-emitting device.

FIG. 15 illustrates a specific example of an electric appliance.

FIG. 16 illustrates a specific example of an electric appliance.

FIG. 17 illustrates a circuit configuration of a light-emitting device.

FIG. 18 illustrates a circuit configuration of a light-emitting device.

FIG. 19 illustrates a cross-sectional structure of a light-emitting device.

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Claims (36)

[Claims] 1. A light-emitting device including an organic light-emitting element having an anode, a cathode, and an organic compound film interposed between the anode and the cathode, wherein the organic compound film forms holes from the anode. Receiving hole injecting compound, electron injecting compound for receiving electrons from the cathode, hole transporting compound,
An electron-transporting compound, a blocking compound capable of blocking the transfer of holes or electrons, a light-emitting compound emitting light, containing at least two compounds selected from the group, and at least one of the two compounds Is a polymer compound. 2. The light emitting device according to claim 1, wherein the region where the two compounds are mixed exists at a position apart from the anode and the cathode. 3. The light-emitting device according to claim 1, wherein the two compounds are hosts, and a guest is added to a region where the two compounds are mixed. Light emitting device. 4. The light emitting device according to claim 3, wherein the guest is a light emitting compound which emits light. 5. A light emitting device including an anode, a cathode, an organic compound film interposed between the anode and the cathode, and an organic light emitting element having an organic compound film, wherein the organic compound film is a polymer compound. One organic compound, a second organic compound that is a polymer compound different from the first organic compound,
And a mixed region in which the first organic compound and the second organic compound are mixed. 6. A light-emitting device including an organic light-emitting element having an anode, a cathode, and an organic compound film interposed between the anode and the cathode, wherein the organic compound film is a polymer compound. Contains one organic compound and a second organic compound that is a low molecular weight compound capable of being vacuum-deposited, and
A light emitting device having a mixed region in which the first organic compound and the second organic compound are mixed. 7. The light emitting device according to claim 5, wherein the concentration of the first organic compound and the concentration of the second organic compound change continuously in the mixed region. Light emitting device. 8. The light emitting device according to claim 6, wherein the concentration of the first organic compound and the concentration of the second organic compound change continuously in the mixed region. Light emitting device. 9. The light emitting device according to claim 5, wherein the first organic compound has a hole transporting property,
The light emitting device is characterized in that the second organic compound emits light and emits light, and the mixed region is located away from the anode and the cathode. 10. The light emitting device according to claim 5, wherein the first organic compound has an electron transporting property, and the second organic compound has a light emitting property of emitting light. The light emitting device according to claim 1, wherein the mixed region exists at a position apart from the anode and the cathode. 11. The light-emitting device according to claim 6, wherein the first organic compound has a hole-transporting property, and the second organic compound has a light-emitting property to emit light. The light emitting device according to claim 1, wherein the mixed region exists at a position apart from the anode and the cathode. 12. The light emitting device according to claim 6, wherein the first organic compound has an electron transporting property, and the second organic compound has a light emitting property of emitting light. The light emitting device according to claim 1, wherein the mixed region exists at a position apart from the anode and the cathode. 13. The light-emitting device according to claim 6, wherein the first organic compound has a light-emitting property to emit light, and the second organic compound has a hole-transport property, The light emitting device according to claim 1, wherein the mixed region exists at a position apart from the anode and the cathode. 14. The light-emitting device according to claim 6, wherein the first organic compound has a light-emitting property to emit light, and the second organic compound has an electron-transport property. The light emitting device according to claim 1, wherein the mixed region exists at a position apart from the anode and the cathode. 15. The light-emitting device according to claim 9, wherein the first organic compound is a polymer compound containing π electrons, and is chemically doped. Light emitting device. 16. The light emitting device according to claim 9, wherein the first organic compound is a polythiophene derivative, a polyaniline derivative, or a polyvinyl carbazole derivative. 17. The light-emitting device according to claim 9, wherein the second organic compound is a polyparaphenylenevinylene derivative, a polydialkylfluorene derivative, a polyvinylcarbazole derivative, or a polyphenylene derivative. A light emitting device characterized by the above-mentioned. 18. The light-emitting device according to claim 13, wherein the second organic compound is a polyparaphenylenevinylene derivative, a polydialkylfluorene derivative, a polyvinylcarbazole derivative, or a polyphenylene derivative. A light emitting device characterized by the above-mentioned. 19. The light emitting device according to claim 5, wherein the organic compound film contains a third organic compound different from the first organic compound and the second organic compound, The light emitting device is characterized in that the third organic compound is added as a guest to a region containing both the first organic compound and the second organic compound. 20. The light emitting device according to claim 19, wherein
The first organic compound and the second organic compound,
A hole-injecting compound that receives holes from the anode, an electron-injecting compound that receives electrons from the cathode, a hole-transporting compound, an electron-transporting compound, a blocking compound that can block the transfer of holes or electrons, A light-emitting device, wherein the light-emitting device is a compound selected from a group, and the third organic compound is a light-emitting compound that emits light. 21. The light-emitting device according to claim 19, wherein the third organic compound is a light-emitting compound that emits light from a triplet excited state. 22. The light emitting device according to claim 21, wherein
The light emitting device, wherein the third organic compound is a metal complex having platinum as a central metal or a metal complex having iridium as a central metal. 23. The light emitting device according to claim 19,
The light emitting device according to claim 1, wherein the third organic compound has a larger energy difference between the highest occupied molecular orbital and the lowest unoccupied molecular orbital than the first organic compound and the second organic compound. 24. The light emitting device according to claim 19,
The light-emitting device, wherein the third organic compound is a phenanthroline derivative, an oxadiazole derivative, or a triazole derivative. 25. The light emitting device according to claim 7, wherein, among the elements constituting the first organic compound or the second organic compound, a detection amount of the element that can be detected by SIMS is: A light emitting device having a region that changes continuously in the direction from the anode to the cathode. 26. The light-emitting device according to claim 7, wherein the organic compound film contains a Group 15 element to a Group 17 element, and the Group 15 element to a Group 17 element which can be detected by SIMS. A light-emitting device comprising: a region in which a detected amount of an element continuously changes in a direction from the anode to the cathode. 27. The light emitting device according to claim 26,
A light-emitting device, wherein the Group 15 element to the Group 17 element is any one of nitrogen, phosphorus, oxygen, sulfur, fluorine, chlorine, bromine, and iodine. 28. The light-emitting device according to claim 19, wherein the third organic compound is a metal complex having a metal element, and the detection area of the metal element that can be detected by SIMS is the first organic compound. A light-emitting device, which is a region containing both the organic compound and the second organic compound. 29. The light emitting device according to claim 28,
The light emitting device, wherein the metal element is aluminum, zinc, or beryllium. 30. The light emitting device according to claim 28,
The light emitting device, wherein the metal element is iridium or platinum. 31. A first solution comprising a first organic compound and a first solvent is wet-coated on a substrate having electrodes, and the first solution is vapor-deposited with a vapor pressure of the first solvent. Is heated to a temperature below the pressure of the working atmosphere, and then the second
A method for manufacturing a light emitting device including an organic light emitting element, comprising applying a second solution composed of the organic compound and a second solvent. 32. A first solution comprising a first organic compound and a first solvent is wet-coated on a substrate having electrodes and dried by heating, and then the solvent contained in the first solution is removed. A method for manufacturing a light-emitting device including an organic light-emitting element, comprising applying a second solution composed of a second organic compound and a second solvent in a state included in a working atmosphere. 33. After forming a film of a first organic compound on a substrate having an electrode, when wet-coating a second solution comprising a second organic compound and a second solvent, 2
A method of manufacturing a light emitting device including an organic light emitting element, wherein the solubility of the second organic compound in the solvent is higher than that of the first organic compound. 34. After forming a first organic compound on a substrate having an electrode, the first organic compound is dissolved in a working atmosphere in a solvent capable of dissolving the first organic compound. A method for manufacturing a light emitting device including an organic light emitting element, wherein a second solution composed of a second solvent is wet-coated. 35. A first solution in which a first organic compound is dissolved is wet-coated on a substrate having electrodes, and then a second organic compound is formed into a film by vacuum deposition in a vacuum chamber. A method for manufacturing a light-emitting device including an organic light-emitting element, wherein the method includes heating and drying. 36. The manufacturing method according to claim 35, wherein
The method for manufacturing a light emitting device including an organic light emitting element, wherein the heating and drying is performed under a reduced pressure of 10 ⁻⁴ Pa or less.