KR102092551B1 - Organic Light Emitting Display Device and Manufacturing Method of the same - Google Patents

Abstract

The present invention is a display panel; And red, green, and blue sub-pixels formed on the display panel, wherein the red, green, and blue sub-pixels each include an electron transport layer positioned between the emission layer and the upper electrode, wherein the electron transport layer includes at least two different materials. It provides an organic electroluminescent display device characterized in that the mixture is formed by a solution process.

Description

Organic light emitting display device and its manufacturing method {Organic Light Emitting Display Device and Manufacturing Method of the same}

The present invention relates to an organic light emitting display device and a method of manufacturing the same.

An organic light emitting device used in an organic light emitting display device is a self-emitting device in which a light emitting layer is formed between two electrodes. In the organic electroluminescent device, electrons and holes are injected into the emission layer from the electron injection electrode (cathode) and the hole injection electrode (anode), respectively, and the exciton in which the injected electrons and holes are combined is excited. It is a device that emits light when it falls from the ground to the ground.

An organic light emitting display device using an organic light emitting device includes a top-emission method, a bottom-emission method, and a dual-emission method according to the direction in which light is emitted, and a driving method. It is divided into passive matrix type and active matrix type.

In the organic light emitting display device, when a scan signal, a data signal, and a power supply are supplied to a plurality of sub-pixels arranged in a matrix form, the selected sub-pixel emits light to display an image.

As a method of manufacturing a display panel of an organic light emitting display device, there are a hybrid method in which a deposition method and a solution (or solution) method and a deposition method and a solution method are combined.

As described above, a method in which a solution process is added is studied to reduce production cost through process simplification. However, the conventionally proposed method has a problem in that the light emitting layer is damaged by the solvent of the electron transport layer formed after the light emitting layer included in the organic light emitting layer. Therefore, in the conventionally proposed method, all the layers of the organic light-emitting layer could not be formed by a solution process because the performance of the device was significantly reduced when the electron transport layer was formed.

The present invention for solving the above-described problems of the background is formed through a solution process from the hole injection layer to the electron transport to simplify the process, and at least two electron transport materials having different characteristics are mixed as an electron transport layer, red, It is to provide an organic light emitting display device capable of lowering the driving voltage of green and blue sub-pixels and improving light efficiency, and a manufacturing method thereof.

The present invention as a means for solving the above problems is a display panel; And red, green, and blue sub-pixels formed on the display panel, wherein the red, green, and blue sub-pixels each include an electron transport layer positioned between the emission layer and the upper electrode, wherein the electron transport layer includes at least two different materials. It provides an organic electroluminescent display device characterized in that the mixture is formed by a solution process.

The at least two heterogeneous materials may be at least one of homo / lumo level, triplet level, glass transition temperature, and hole mobility.

The electron transport layer is a mixture of three heterogeneous materials including the A material, the B material, and the C material, and the A material has a higher glass transition temperature than the B material and the C material and a low Lumo level. Selected as a material, the B material is selected as a material having a higher homo level and a triplet level compared to the A material and the C material, and the C material is a hole compared to the A material and the B material It can be selected as a material with low mobility.

The mixing ratio of the A material, the B material, and the C material may have a relationship between the A material = the B material> and the C material.

The A and B materials may account for 30 to 40 parts by weight, and the C material may occupy 10 to 20 parts by weight with respect to 100 parts by weight of the electron transport layer.

In another aspect, the present invention includes forming a lower electrode on a lower substrate using a deposition process; Forming a hole injection layer, a hole transport layer, a light emitting layer and an electron transport layer on the lower electrode using a solution process; And forming an upper electrode on the electron transport layer using the deposition process, wherein the electron transport layer provides a method of manufacturing an organic light emitting display device, characterized in that at least two different materials are mixed. .

The light emitting layer and the electron transport layer may be dissolved by different solvents.

The electron transport layer is a mixture of three heterogeneous electron transport materials including the A material, the B material, and the C material, and the A material has a higher glass transition temperature than the B material and the C material and has a Lumo level. This low material is selected, and the B material is selected as a material having a higher homo level and a triplet level compared to the A material and the C material, and the C material is compared to the A material and the B material It can be selected as a material having low hole mobility.

The mixing ratio of the A material, the B material, and the C material may have a relationship between the A material = the B material> and the C material.

The A and B materials may account for 30 to 40 parts by weight, and the C material may occupy 10 to 20 parts by weight with respect to 100 parts by weight of the electron transport layer.

The present invention has an effect of providing an organic electroluminescence display device and a method of manufacturing the same, which can be simplified by forming a process from a hole injection layer to an electron transport through a solution process. In addition, the present invention is an electron transport layer made of a mixture of at least two electron transport materials having different characteristics, and an organic electroluminescence display device capable of lowering the driving voltage of red, green and blue sub-pixels and improving light efficiency, and a method of manufacturing the same. It has the effect of providing.

1 is a block diagram schematically showing an organic light emitting display device according to an embodiment of the present invention.
FIG. 2 is an exemplary view of the sub-pixel shown in FIG. 1.
3 is a view schematically showing a cross-section of the display panel shown in FIG. 1;
4 is a first exemplary view showing a part of FIG. 3 in detail;
5 is a second exemplary view showing a part of FIG. 3 in detail;
6 is a view for explaining a solution process method according to an embodiment of the present invention and a solution process method proposed in the prior art.
7 is a graph showing characteristics of a light emitting layer before and after rinsing.
8 is a characteristic graph for a structure without an electron transport layer, a structure in which the electron transport layer is formed by a deposition process, and a structure in which the electron transport layer is formed by a solution process.
9 is a block diagram of a sub-pixel according to an embodiment of the present invention.
10 is a cross-sectional view of a sub-pixel according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, specific content for the practice of the present invention will be described.

1 is a block diagram schematically showing an organic light emitting display device according to an embodiment of the present invention, FIG. 2 is an exemplary view of a sub-pixel shown in FIG. 1, and FIG. 3 is a view of the display panel shown in FIG. 1. FIG. 4 is a first exemplary view showing a part of FIG. 3 in detail, and FIG. 5 is a second exemplary view showing a part of FIG. 3 in detail.

As illustrated in FIG. 1, the organic light emitting display device according to an exemplary embodiment of the present invention includes a timing control unit 120, a scan driving unit 130, a data driving unit 140, and a display panel 150.

The timing control unit 120 collects device information (Extended Display Identification Data; EDID) including the resolution, frequency, and timing information of the display panel 150 from the external memory unit through an I2C interface or the like, or compensation data. The timing controller 120 outputs a gate timing control signal GDC for controlling the operation timing of the scan driver 130 and a data timing control signal DDC for controlling the operation timing of the data driver 140. The timing controller 120 supplies the data signal DATA with the data timing control signal DDC to the data driver 140.

The data driver 140 samples, latches, and converts and outputs the data signal DATA into a gamma reference voltage in response to the data timing control signal DDC supplied from the timing controller 120. The data driver 140 may be formed of an integrated circuit (IC) and mounted on the display panel 150 or an external substrate connected to the display panel 150. The data driver 140 supplies a data signal DATA to the sub pixels SP included in the display panel 150 through the data lines DL.

The scan driver 130 outputs a scan signal while shifting the level of the gate voltage in response to the gate timing control signal GDC supplied from the timing controller 120. The scan driver 130 may be formed of an integrated circuit and mounted on the display panel 150 or may be mounted on an external substrate connected to the display panel 150. Also, the scan driver 130 may be formed on the display panel 150 in the form of a gate in panel. The scan driver 130 supplies a scan signal to sub-pixels SP included in the display panel 150 through scan lines GL.

The display panel 150 displays an image in response to the scan signal supplied from the scan driver 130 and the data signal DATA supplied from the data driver 140. The display panel 150 includes sub-pixels SP controlling light to display an image. The display panel 150 is implemented in a top-emission method, a bottom-emission method, or a dual-emission method according to the structure of the sub-pixels SP.

As shown in FIG. 2, one sub-pixel SP is supplied corresponding to the scan signal supplied through the switching transistor SW and the switching transistor SW connected to the scan line GL1 and the data line DL1. A pixel circuit PC operating in response to the data signal DATA is included.

The pixel circuit PC includes a driving transistor, a capacitor, and an organic light emitting diode. When a driving transistor, a capacitor, and an organic light-emitting diode are included in the pixel circuit PC, the sub-pixel SP has a 2T (Transistor) 1C (Capacitor) structure. However, when a compensation circuit for compensating a driving transistor, as well as a driving transistor, a capacitor, and an organic light emitting diode is added to the pixel circuit PC, it is composed of 3T1C, 4T1C, and 5T2C.

The sub pixels SP include a red sub pixel, a green sub pixel, and a blue sub pixel. However, the structure including white sub-pixels, red sub-pixels, green sub-pixels, and blue sub-pixels may be configured to increase luminance of the display panel 150 and prevent deterioration of luminance and color deterioration of pure colors. In this case, the white sub-pixel, the red sub-pixel, the green sub-pixel, and the blue sub-pixel are implemented by using a white organic light emitting diode and an RGB color filter, or the white, red, green, and blue light emitting materials included in the organic light emitting diode are used. It is implemented in a manner that is formed by dividing.

As shown in FIG. 3, the display panel 150 includes a lower substrate 151 and an upper substrate 152. The lower substrate 151 and the upper substrate 152 are bonded by an adhesive such as sealant. However, when the upper substrate 152 is formed in a film form, it is formed on the lower substrate 151 in the form of a deposition.

Sub-pixels including an organic light emitting diode and the like are formed on one surface of the lower substrate 151. Sub-pixels including organic light emitting diodes are vulnerable to external air such as oxygen and moisture. Accordingly, an upper substrate 152 capable of sealing sub-pixels is formed on the lower substrate 151.

A protective film 155 protecting the upper surface of the display panel 150 is formed on the upper substrate 152. The protective film 155 serves to prevent damage to the display panel 150 from external stimuli or impact that may be applied to the upper surface of the display panel 150, which may be omitted.

4 and 5, a switching transistor (not shown), a driving transistor DR, a capacitor (not shown), and an organic light emitting diode (OLED) are formed on one surface of the lower substrate 151. The switching transistor (not shown), the driving transistor DR, the capacitor (not shown), and the organic light emitting diode OLED are connected to various wirings formed on one surface of the lower substrate 151.

The driving transistor DR includes a gate electrode 161, a semiconductor layer 163, a source electrode 164a and a drain electrode 164b. The gate electrode 161 is formed on one surface of the lower substrate 151. The first insulating layer 162 is formed on the gate electrode 161. The semiconductor layer 163 is formed on the first insulating film 162. The source electrode 164a and the drain electrode 164b are formed to contact one side and the other side of the semiconductor layer 163. A second insulating film 165 is formed on the source electrode 164a and the drain electrode 164b.

The organic light emitting diode (OLED) includes a lower electrode 166, an organic emission layer 168, and an upper electrode 169. The lower electrode 166 is formed on the second insulating film 165. The lower electrode 166 is formed to be connected to the drain electrode 164b of the driving transistor DR exposed through the second insulating layer 165. The lower electrode 166 is formed separately for each sub-pixel. The lower electrode 166 is selected as the anode electrode (or cathode electrode). The bank layer 167 is formed on the lower electrode 166. The bank layer 167 is a layer that defines the opening area of the sub-pixel. The organic emission layer 168 is formed on the lower electrode 166.

The organic emission layer 168 includes a hole injection layer (HIL), a hole transport layer (HTL), a light emitting layer (EML), an electron transport layer (ETL), and an electron injection layer (EIL). However, at least one of the functional layers HIL, HTL, ETL, and EIL other than the emission layer EML of the organic emission layer 168 may be omitted. The upper electrode 169 is formed on the organic emission layer 168. The upper electrode 169 is formed in the form of a face electrode commonly connected to all sub-pixels. The upper electrode 169 is selected as a cathode electrode (or anode electrode).

4, the upper substrate 152 may be formed in a multi-layer film form or a single film form, although not shown. When the upper substrate 152 is formed in the form of a multilayer film, it may be formed of an organic film and an inorganic film, and when the upper substrate 152 is formed in a single-layer film form, it may be formed of an organic film or an inorganic film.

As illustrated in FIG. 5, the upper substrate 152 may be formed in an N (N is an integer of 3 or more) layer film. In this case, the upper substrate 152 may be formed of an organic / inorganic composite layer composed of an organic layer 152a, an inorganic layer 152b, an organic layer 152c, and an inorganic layer 152d. Although not shown, the inside of the organic-inorganic composite layer may further include a moisture absorbing layer that absorbs moisture or oxygen.

On the other hand, in the case of an organic light emitting display device, in order to improve the productivity of a display panel, the development of a device using a solution process such as a solution or a solution method is being studied. The solution process is a method of forming the organic light emitting layer 168 of the organic light emitting diode by inkjet printing, nozzle printing, transfer method, slit coating, gravure printing, and thermal jet printing.

6 is a view for explaining a solution process method according to an embodiment of the present invention and a conventionally proposed solution process method, and FIG. 7 is a graph showing characteristics of a light emitting layer before and after rinsing.

As shown in FIG. 6 (a), the conventionally proposed solution process method uses a solution process from a hole injection layer to a light emitting layer (168RGB), and an electron transport layer (168_ETL) formed after the light emitting layer (168RGB) It is proceeding from the deposition process (Evap.). The reason is that during the solution process, a problem occurs in that the light emitting layer 168RGB positioned in the lower layer is damaged by the solvent of the electron transport layer 168_ETL formed in the upper layer. Therefore, in the conventionally proposed method, since the performance of the device is greatly deteriorated when the electron transport layer 168_ETL is formed, it is not possible to form all the layers of the organic light emitting layer by a solution process.

As shown in Figure 6 (b), the solution process method according to an embodiment of the present invention can be formed through a solution process from the hole injection layer to the electron transport layer (168_ETL) while preventing damage to the light emitting layer (168RGB) However, this can be seen through the following description and experimental results.

As described above, when the conventionally proposed solution process is used, the light emitting layer positioned on the lower layer is damaged by the solvent of the electron transport layer formed on the upper layer. In the present invention, in order to overcome this problem, an experiment was conducted to find a solvent in which the light emitting layer was not damaged.

The experiment was conducted by selecting a light emitting layer made of a polymer material, dropping various types of solvent thereon, and measuring the degree of damage to the light emitting layer. At this time, the measurement of the degree of damage to the light-emitting layer was performed using ultraviolet (UV) measurement and an optical microscope, and the thin film state of the light-emitting layer was conditioned after the rinsing, that is, a solvent that does not damage the light-emitting layer.

Solvent found in the present invention is an alcohol (alcohol) series, as shown in Fig. 7 (a), there was no abnormality in the thin film state of the light emitting layer before and after rinsing on the spectrum, and also using an optical microscope as shown in Fig. 7 (b). Even the measured results did not show any specific problems.

The solvent found through FIG. 7 was a material different from the solvent used in the light emitting layer made of a polymer material. As revealed through experiments, when the solvent used in the light-emitting layer and the solvent used in the electron-transporting layer are the same, the solvent of the electron-transporting layer melts the solvent in the light-emitting layer during the solution process, thereby damaging the light-emitting layer.

Therefore, the solvent of the electron transport layer should be a material that cannot dissolve (or damage) the solvent of the light emitting layer. That is, the first solvent used in the light emitting layer and the second solvent used in the electron transport layer should be different materials. In addition, the polymer material used in the light emitting layer should have properties that are not easily dissolved in alcohol.

In the present invention, a method for improving the characteristics of the electron transport layer was sought while revealing that the electron transport layer can be formed by a solution process using a solvent in which the light emitting layer is not damaged.

In the case of the electron transport layer, the characteristics of the device may be improved when the HOMO level has a deep characteristic and a hole blocking role is actively performed. Since the electron transport layer can be formed through a solution process, it was revealed through previous experiments that the materials in Table 1 were mixed to have these properties. "HOMO / LUMO" in Table 1 are homo-and rumo level, "T1" is triplet level, "Tg" is the glass transition temperature, "μ _h" refers to a hole mobility.

As can be seen from Table 1, the material A (Material-A), material B (Material-B) and material C (Material-C) are homo / lumo level, triplet level, glass transition temperature and hole movement. The degrees are all selected from different materials. In addition, the A material (Material-A), the B material (Material-B), and the C material (Material-C) have an advantage of being differentiated from other materials for each material. The material A (Material-A), material B (Material-B), and material C (Material-C) have electron transport capability (eg, material A) or hole blocking capability (eg, material B). It has been disclosed as an example, but is not limited thereto.

For example, in the case of the material A (Material-A), the glass transition temperature is higher than the material B (Material-B) and material C (Material-C) and the lumo level is low. In addition, in the case of the B material (Material-B), the homo level is higher and the triplet level is higher than that of the A material (Material-A) and the C material (Material-C). In the case of the material C (Material-C), the hole mobility is lower than that of the material A (Material-A) and the material B (Material-B).

Particularly, in the case of the material B (Material-B), since the homo level is high and the mobility of holes is low compared to the material A (Material-A) and the material C (Material-C), not only electrons are transferred, but also hole blocking (hole) blocking) is also possible.

Therefore, the material A (Material-A) and the material B (Material-B) are composed of the basic material and the material C (Material-C) is composed of the additive material, but the mixing ratio of the material C (Material-C) By adjusting, you will be able to control the mobility of the holes.

In the present invention, when the electron transport layer is formed in a solution process as in the experimental example, 40 parts by weight of the material A (Material-A), material B (Material-B) and material C (Material-C) are 40 parts by weight. Part: 20 parts by weight.

As described above, since the lumo level is excellent in the case of the material A (Material-A), and the homo level is excellent in the case of the material B (Material-B), it is preferable that the two materials are mixed in similar proportions.

The mixing ratio of the material A (Material-A) and the material B (Material-B) may change depending on the harmony with the light emitting layer, but since it is a basic material, it occupies 30 to 40 parts by weight for 100 parts by weight of the electron transport layer. It is preferred.

Since the material C (Material-C) corresponds to an additive material added to control hole mobility, it is preferable to occupy 10 to 20 parts by weight based on 100 parts by weight of the electron transport layer. However, when the mixing ratio of the material (C) (Material-C) is lower than 10 parts by weight, it is difficult to control the mobility of the hole, thereby deteriorating the blocking ability of the hole. In addition, when the mixing ratio of the material C (Material-C) is higher than 20 parts by weight, electron injection or blocking of holes is prevented.

On the other hand, in the present invention, when mixing the A material (Material-A), the B material (Material-B) and the C material (Material-C) and forming the electron transport layer through a solution process, the following method is used. You can.

-How to mix after dissolving each substance in solvent-

After dissolving material A (Material-A), material B (Material-B) and material C (Material-C) in a solvent, the solution is mixed. In the previous experiments, each material was dissolved in a proportion of 1 part by weight in the solvent, and as a result, it was found to have a viscosity of about 10c.p (centifaz). However, it is needless to say that the dissolution ratio for each material can be changed (viscosity control) according to the thickness of the thin film.

The method of dissolving and mixing each material in the solvent can confirm the state in which the powder-like A material (Material-A), B material (Material-B) and C material (Material-C) are dissolved in the solvent. .

-How to dissolve in solvent after mixing materials-

The first material (Material-A), the second material (Material-B), and the second material (Material-C) are mixed and dissolved in a solvent.

The method of dissolving in a solvent after mixing the substances may be performed after dissolving each substance in a solvent and then mixing the substances, and then confirming the dissolution state of each substance. This method can improve the yield in the manufacturing process compared to the method of dissolving and mixing each material in a solvent.

Hereinafter, a material A (Material-A), a material B (Material-B) and a material C (Material-C) are mixed and an electron transport layer is formed through a solution process (Example), and there is no electron transport layer structure. (Comparative Example 1) and the comparison result between the structure in which the electron transport layer was formed by a deposition process (Comparative Example 2) will be described.

8 is a characteristic graph of a structure without an electron transport layer, a structure in which the electron transport layer is formed by a deposition process, and a structure in which the electron transport layer is formed by a solution process.

As shown in FIG. 8, for a structure without an electron transport layer (Non-ETL), a structure with an electron transport layer formed by a deposition process (Evap. ETL), and a structure with an electron transport layer formed by a solution process (Sol. ETL) The voltage current (VJ plot), luminance and brightness (Lum. Vs cd / A) and spectrum graphs are shown.

-Comparative Example 1: Structure without electron transport layer (Non-ETL)-

The structure without electron transport layer (Non-ETL) is the voltage current (VJ plot) and spectrum compared to the structure formed with the electron transport layer by the deposition process (Evap. ETL) and the structure formed with the electron transport layer by the solution process (Sol. ETL). Spectrum) showed no difference in properties. However, the structure without an electron transport layer (Non-ETL) has a luminance and brightness (Lum. Vs. a structure in which the electron transport layer is formed by a deposition process (Evap. ETL) and a structure in which the electron transport layer is formed by a solution process (Sol. ETL). It can be seen that cd / A) is greatly reduced.

-Comparative Example 2: Structure of electron transport layer formed by deposition process (Evap. ETL)-

The structure of the electron transport layer formed by the deposition process (Evap. ETL) has a difference in characteristics on the spectrum compared to the structure without the electron transport layer (Non-ETL) and the structure of the electron transport layer formed by the solution process (Sol. ETL). Did not appear. However, the structure in which the electron transport layer was formed by the deposition process (Evap. ETL) showed a slightly higher voltage current (V-J plot) than the structure in which the electron transport layer was formed by the solution process (Sol. ETL). In addition, it can be seen that the structure (Evap. ETL) in which the electron transport layer is formed by the deposition process is slightly lower in luminance and brightness (Lum. Vs cd / A) than the structure in which the electron transport layer is formed by the solution process (Sol. ETL). .

-Example: Structure of electron transport layer formed by solution process (Sol. ETL)-

The structure in which the electron transport layer is formed by a solution process (Sol. ETL) has a lower characteristic in the spectrum than the structure without an electron transport layer (Non-ETL) and the structure in which the electron transport layer is formed by a deposition process (Evap. ETL). Did not appear. However, the structure in which the electron transport layer is formed by the solution process (Sol. ETL) has a structure without the electron transport layer (Non-ETL) and the voltage current (VJ plot) compared to the structure in which the electron transport layer is formed by the deposition process (Evap. ETL). It appeared rather low. In addition, the structure in which the electron transport layer is formed by the solution process (Sol. ETL) is compared to the structure without the electron transport layer (Non-ETL) and the structure in which the electron transport layer is formed by the deposition process (Evap. ETL) compared to the luminance and brightness (Lum. Vs. cd / A) is somewhat improved.

As can be seen from the above experimental results, the structure in which the electron transport layer is formed by the deposition process (Evap. ETL) has a luminance and brightness (Lum. Vs cd / A) of approximately 60 compared to the structure without the electron transport layer (Non-ETL). % Increase. However, the structure in which the electron transport layer is formed by the solution process (Sol. ETL) has a brightness and brightness (Lum. Vs cd / A) of about 13% higher than the structure in which the electron transport layer is formed by the deposition process (Evap. ETL). .

Therefore, the structure in which the electron transport layer is formed by the solution process (Sol. ETL) has a high HOMO level of 9.6 eV compared to the structure in which the electron transport layer is formed by the deposition process (Evap. ETL), so it functions as a hole blocking. This is active, and luminance and brightness (Lum. Vs cd / A) are excellent.

9 is a configuration diagram of a sub-pixel according to an embodiment of the present invention, and FIG. 10 is a cross-sectional view of a sub-pixel according to an embodiment of the present invention.

As illustrated in FIG. 9, a sub-pixel according to an embodiment of the present invention includes a lower electrode 166, an organic emission layer 168, and an upper electrode 169. The lower electrode 166 is selected as the anode electrode, and the upper electrode 169 is selected as the cathode electrode.

The organic emission layer 168 includes a hole injection layer 168_HIL, a hole transport layer 168_HTL, a red, green and blue emission layer 168RGB, and an electron transport layer 168_ETL. The electron transport layer 168_ETL is composed of a layer (Mixing ETL) in which at least two heterogeneous electron transport materials having different characteristics are mixed as described in the above-described experimental example. However, in order to perform hole blocking to control hole mobility, mixing three different electron transport materials with different characteristics is advantageous in improving luminance and brightness (Lum. Vs cd / A). Do.

10, a hole injection layer 168_HIL is formed on the lower electrode 166, and a hole transport layer 168_HTL is formed on the hole injection layer 168_HIL. The red, green, and blue emission layers 168RGB are formed on the hole transport layer 168_HTL, and the electron transport layer 168_ETL is formed on the red, green, and blue emission layers 168RGB. The electron injection layer and the upper electrode 169 are formed on the electron transport layer 168_ETL.

The hole injection layer 168_HIL, the hole transport layer 168_HTL, the red, green, and blue light emitting layers 168RGB and the electron transport layer 168_ETL are formed by a solution or solution method, and the electron injection layer and the upper electrode 169 ) Is formed by an evaporation process. The solution or solution process includes inkjet printing, nozzle printing, transfer, slit coating, gravure printing and thermal jet printing as a solution process.

As described above, the present invention has an effect of providing an organic light emitting display device and a method for manufacturing the organic electroluminescent display device that can simplify the process by forming the hole injection layer to the electron transport through a solveable process. In addition, the present invention is an electron transport layer made of a mixture of at least two electron transport materials having different characteristics, and an organic electroluminescence display device capable of lowering the driving voltage of red, green, and blue sub-pixels and improving light efficiency. It has the effect of providing.

The embodiments of the present invention have been described above with reference to the accompanying drawings, but the technical configuration of the present invention described above is in other specific forms without changing the technical spirit or essential features of the present invention by those skilled in the art to which the present invention pertains. It will be understood that it can be practiced. Therefore, the embodiments described above are to be understood in all respects as illustrative and not restrictive. In addition, the scope of the present invention is indicated by the claims below, rather than the detailed description. In addition, all modifications or variations derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention.

120: timing control unit 130: scan driver
140: data driving unit 150: display panel
166: lower electrode 168: organic light emitting layer
168_HIL: hole injection layer 168_HTL: hole transport layer
168R, 168G, 168B: light emitting layer 168_ETL: electron transport layer
169: upper electrode

Claims (10)

A lower electrode spaced apart from the upper electrode;
A light emitting layer disposed between the upper electrode and the lower electrode and formed in red, green, and blue sub-pixels as a light-emitting material dissolved in a first solvent; And
An electron transport layer disposed between the light emitting layer and the upper electrode, and formed by mixing an electron transport material in which at least three different materials dissolved in a second solvent are mixed; Including,
The second solvent, which is different from the first solvent, is an alcohol-based material that does not dissolve the luminescent material and dissolves the electron transport material in which the at least three heterogeneous materials are mixed,
The electron transport layer is an organic electroluminescent display device characterized in that the electron transport material is formed by mixing at least one of homo / lumo level, triplet level, glass transition temperature and hole mobility through a solution process.
delete According to claim 1,
The electron transport layer
Three heterogeneous materials including the A material, the B material and the C material are mixed,
The material A is selected as a material having a high glass transition temperature and a low lumo level compared to the material B and the material C,
The B material is selected as a material having a higher homo level and a higher triplet level than the A material and the C material,
The C material is an organic electroluminescent display device characterized in that the material is selected as a material having a lower hole mobility than the A material and the B material. According to claim 3,
The mixing ratio of the A material, the B material, and the C material is
The A material = the B material> the organic electroluminescent display device, characterized in that has a relationship of the C material. According to claim 3,
For the total 100 parts by weight of the electron transport layer
The A and B materials occupy 30 to 40 parts by weight,
The C material is an organic electroluminescence display device, characterized in that occupies 10 to 20 parts by weight. Forming a lower electrode on the lower substrate using a deposition process;
Forming a hole injection layer, a hole transport layer, a light emitting layer and an electron transport layer on the lower electrode using a solution process; And
And forming an upper electrode on the electron transport layer using the deposition process,
The light emitting layer is formed of a light emitting material dissolved in the first solvent,
The electron transport layer is formed of an electron transport material in which at least three or more different materials dissolved in the second solvent different from the first solvent are mixed,
The second solvent is a method of manufacturing an organic light emitting display device, characterized in that it is made of an alcohol-based material that does not dissolve the luminescent material and dissolves the at least three or more dissimilar materials.
delete The method of claim 6,
The electron transport layer
Three heterogeneous electron transport materials including the A material, the B material and the C material are mixed,
The material A is selected as a material having a high glass transition temperature and a low lumo level compared to the material B and the material C,
The B material is selected as a material having a higher homo level and a higher triplet level than the A material and the C material,
The C material is a method of manufacturing an organic light emitting display device, characterized in that the material is selected as a material having a lower hole mobility than the A material and the B material. The method of claim 8,
The mixing ratio of the A material, the B material, and the C material is
The A material = the B material> a method of manufacturing an organic light emitting display device, characterized in that it has a relationship of the C material. The method of claim 8,
For the total 100 parts by weight of the electron transport layer
The A and B materials occupy 30 to 40 parts by weight,
The method for manufacturing an organic light emitting display device, characterized in that the C material occupies 10 to 20 parts by weight.

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