KR20050027465A - Filed organic electroluminescent display device - Google Patents

Abstract

A multilayer organic electroluminescence display device is provided to comprise upper/lower electrodes and substrates to be independently driven by RGB colors without fine pattern masks, thereby reducing brightness requirements for configuring a full color device while decreasing current consumption. The first organic electroluminescence device factor(100) comprises as follows. The first electrodes(12) are formed on the first substrate(10). The first organic emitting layer(16) is formed on the first electrodes(12). The second electrode is formed on the first organic emitting layer(16). The second organic electroluminescence device factor(200) comprises as follows. The second substrate(20) is formed on the first device factor(100). The third electrodes(22) are formed on the second substrate(20). The second organic emitting layer(26) is formed on the third electrodes(22). The fourth electrode is formed on the second organic emitting layer(26). The third organic electroluminescence device factor(300) comprises as follows. The third substrate(30) is formed on the second device factor(200). The fifth electrodes(32) are formed on the third substrate(30). The third organic emitting layer(36) is formed on the fifth electrodes(32). The sixth electrode(38) is formed on the third organic emitting layer(36).

Description

Multilayer Organic Electroluminescent Device {FILED ORGANIC ELECTROLUMINESCENT DISPLAY DEVICE}

[Industrial use]

The present invention relates to a stacked organic electroluminescent device, and more particularly, to a stacked organic electroluminescent device implementing full color.

[Prior art]

2. Description of the Related Art In general, an organic light emitting display device is an active light emitting display device, and has been attracting attention as a next generation display device because of its advantages of wide viewing angle, excellent contrast, and fast response speed.

The organic electroluminescent device is classified into an inorganic EL device and an organic EL device according to a material for forming an emitting layer. Herein, the organic EL device has an advantage of excellent luminance, driving voltage, and response speed characteristics, and multicoloring, in comparison with the inorganic EL device.

1 is a cross-sectional view schematically showing the structure of a stacked organic electroluminescent device disclosed in U.S. Patent Nos. 5,703,436, 5,917,280, 5,932,895, and 6,232,714.

Referring to FIG. 1, light emitting diodes 20, 21, and 22 are stacked on a glass substrate 37 including a reflective film 38. The LED 20 is located under the organic EL device of the laminated structure, the LED 21 is formed at the middle of the laminated structure, and the LED 22 is formed at the upper end of the laminated structure. The laminated structure has a vertical structure, as shown in FIG. In the LED 20, a hole transport layer (HTL) 20H is laminated on the surface of the ITO, an EL layer 20E is disposed thereon, and an ETL layer 20T is formed on the EL layer. As the material forming the HTL, EL, and ETL layers, known organic materials are used.

On the ETL layer 20T, a metal layer 26M is formed of a translucent metal having a work function of 4 eV or less. Metals such as Mg and Mg / Ag are used. A transparent thin film conductive ITO layer 26I is laminated on the metal layer 26M (ITO / metal layer 26 formed). LEDs 20, 21, and 22 each have a HTL layer formed on top of a transparent conductive layer 26I or 35 as a bottom layer. Then, another EL layer and an ETL layer are formed again. HTL, ETL, ITO, metal and organic EL layers are transparent. The EL layer and the ETL layer may be composed of a single layer.

In addition, the LED 20 is positioned below the blue light emitting layer. Then, LED 21 which is a green light emitting layer and LED 22 which is a red light emitting layer are formed on it.

In the present invention, the lower electrode of the light emitting diode LED 20 and the upper electrode of the LED 21 are shared, and the lower electrode of the light emitting diode LED 21 and the upper electrode of the light emitting diode 20 are shared.

In addition, when a voltage must be applied to drive each diode during driving, a voltage is applied through the contacts 30, 31, and 32.

However, in the stacked organic EL device formed as described above, each of the organic light emitting diode LEDs 20, 21, and 22 is not formed independently, but the LEDs 22, 21, and 20 must be sequentially formed, but the organic light emitting layer 22E is formed. In this case, it is difficult to apply a heat treatment process or a wet process to form an upper layer. In addition, each LED 20, 21, 22 cannot be formed and combined independently during manufacturing. I have a difficulty. And, there is a problem in that the process conditions are limited because the layers must be sequentially stacked.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems described above, and the object of the present invention is not limited to the manufacturing process conditions, and the limitations and luminance of the color patterning of the full color organic electroluminescent display on a high resolution, ultra-large substrate, It is to provide a stacked organic electroluminescent device that can solve the life.

The present invention to achieve the above object, the present invention

A first substrate;

A first electrode formed on the first substrate;

A first organic light emitting layer formed on the first electrode; And

A first organic electroluminescent device element comprising a second electrode formed on the first organic light emitting layer,

A second insulating substrate formed on the first organic electroluminescent element;

A third electrode formed on the second substrate;

A second organic light emitting layer formed on the third electrode; And

A second organic electroluminescent device element comprising a fourth electrode formed on the second organic light emitting layer,

A third insulating substrate formed on the second organic electroluminescent element element;

A fifth electrode formed on the third substrate;

A third organic light emitting layer formed on the fifth electrode; And

It provides a stacked organic electroluminescent device comprising a third organic electroluminescent device element comprising a sixth electrode formed on the third organic light emitting layer.

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

2 is a cross-sectional view schematically illustrating a structure of a stacked organic electroluminescent device according to an embodiment of the present invention.

Referring to FIG. 2, a stacked organic electroluminescent device according to an embodiment of the present invention includes a first organic electroluminescent device element 100, a second organic electroluminescent device element 200, and a third organic electroluminescent device element. It consists of 300.

The first organic electroluminescent element 100 may include a first substrate 10 below and a first electrode 12 above the first substrate 10, and the first electrode may be a pixel defined layer. Layer (PDL) 14 defines a pixel area. The first organic light emitting layer 16 is disposed in this pixel region. Then, the first organic electroluminescent device element 100 is provided to be driven independently by forming a second electrode on the first organic light emitting layer 16.

Subsequently, the second organic electroluminescent element 200 is disposed on the first organic electroluminescent element 100. The second organic electroluminescent element 200 has the same configuration as the first organic electroluminescent element 200. That is, the second organic electroluminescent element 200 includes a second substrate 20 at the bottom, a third electrode 22 disposed thereon, and the third electrode 22 is a pixel defined layer. PDL 24 defines the pixel area. The second organic light emitting layer 26 is disposed in this pixel region. Then, the second organic electroluminescent device element 200 is provided so as to be driven independently by forming a fourth electrode on the second organic light emitting layer 26.

Subsequently, a third organic electroluminescent element 300 is again provided on the second organic electroluminescent element 200. The third organic electroluminescent element 300 is also configured in the same manner as the first and second organic electroluminescent element elements.

That is, the third organic electroluminescent element 300 has a third substrate 30 at the bottom, a fifth electrode 32 is disposed thereon, and the fifth electrode 32 is a pixel defined layer. PDL 34 defines the pixel area. The third organic light emitting layer 36 is disposed in this pixel region. Then, the third organic electroluminescent device element 300 is provided to be driven independently by forming a sixth electrode on the third organic light emitting layer 36.

As described above, the stacked organic electroluminescent device according to an embodiment of the present application includes at least three independent organic electroluminescent device elements, and such an independently driveable organic electroluminescent device element should implement a full color. Each of the three organic electroluminescent element elements of the red, blue and green light emitting element must be implemented.

Preferably, a green light emitting layer is formed in the lower portion, a red light emitting layer in the middle thereof, and a blue light emitting layer is formed in the upper portion based on the light extraction direction.

Therefore, if the present invention is a stacked organic electroluminescent device having a top emission structure, the first organic electroluminescent element 100 realizes green light emission, the second organic electroluminescent element 200 implements red light emission, The third organic electroluminescent element 300 implements blue light emission.

That is, the first organic light emitting layer 16 is formed of a green light emitting material, the second organic light emitting layer 26 is formed of a red light emitting material, and the third organic light emitting layer 36 is formed of a blue light emitting material. The green, red, and blue organic light emitting materials are organic light emitting materials that are commonly used, and may be low molecular materials or high molecular materials.

In this case, the first organic electroluminescent element 100 is formed to be reflective because it must reflect light, and the second and third organic electroluminescent elements 200 and 300 should be formed to be transmissive.

Thus, the first electrode 12 of the first organic electroluminescent element element 100 is formed of a metal electrode made of an alloy of Mg or Al of an anode electrode, and the second electrode 18 is a cathode electrode. And ITO, IZO, or the like, which are transparent conductive materials. Alternatively, the first electrode 12 is an anode electrode, and the transparent conductive materials ITO, IZO, and the second electrode 18 are cathode electrodes, and are formed of a metal electrode made of an alloy of Mg or an Al alloy. Further, the third electrode 22 and the fourth electrode 28 of the second organic electroluminescent element 200 and the fifth electrode 32 and the sixth electrode 38 of the third organic electroluminescent element 300. ) Has a structure of a transmissive organic electroluminescent device by using a transparent conductive material as a cathode electrode and a thin metal film as an anode electrode or adopting a reverse structure thereof.

On the other hand, in the case of the bottom emission structure, unlike the top emission structure, the third organic electroluminescent element 300 implements green light emission, and the second organic electroluminescent element 200 implements red light emission, and the first The organic electroluminescent element element 100 realizes blue light emission.

That is, the third organic light emitting layer 36 is formed of a green light emitting material, the second organic light emitting layer 26 is formed of a red light emitting material, and the first organic light emitting layer 16 is formed of a blue light emitting material. The green, red, and blue organic light emitting materials are organic light emitting materials that are commonly used, and may be low molecular materials or high molecular materials.

In this case, since the third organic electroluminescent element 300 must reflect light, the third organic electroluminescent element 300 is formed to be reflective, and the first and second organic electroluminescent elements 100 and 200 should be formed to be transmissive.

Therefore, the sixth electrode 38 of the third organic electroluminescent element 300 is formed of a metal electrode made of Mg alloy or Al alloy as the anode electrode, and includes a reflective film. The fifth electrode 32 becomes a cathode and is formed of ITO, IZO, or the like, which is a transparent conductive material. Further, the third electrode 22 and the fourth electrode 28 of the second organic electroluminescent element 200 and the first electrode 32 and the second electrode 38 of the first organic electroluminescent element 100. The upper electrode has a structure of a transmissive organic electroluminescent element by using a transparent conductive material as a cathode electrode, and using a thin metal film as an anode electrode or adopting a reverse structure thereof.

Meanwhile, in the exemplary embodiment of the present invention, since the pixel regions are defined as the pixel defining layers, the pixel regions of the first organic electroluminescent element element, the pixel regions of the second organic electroluminescent element element, and the third organic electroluminescent element element The pixel areas of must be arranged to match.

In addition, the organic light emitting layer is patterned so that the organic light emitting material is aligned in each of the formed pixel areas formed by stacking the organic light emitting material on each of the organic light emitting layers 16, 26, and 36.

Each of the first, second and third organic EL devices may further include one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole suppression layer, an electron transport layer, and an electron injection layer, as necessary. have.

Since the first, second and third organic electroluminescent device elements are independent devices that can be driven independently of each other, the hole injection layer, the hole transport layer, and the hole suppression layer to improve luminous efficiency and lifetime characteristics in each configuration. It may include one or more layers of the electron transport layer and the electron injection layer.

The hole injection layer, the hole transport layer, the hole suppression layer, the electron transport layer and the electron injection layer may be used a material commonly used as an organic material, regardless of whether a high molecular material or a low molecular material.

Positioning positions of the hole injection layer, the hole transport layer, the hole suppression layer, the electron transport layer and the electron injection layer are used in the position used in the conventional organic electroluminescent device, for example, the hole injection layer, the hole transport layer is a lower electrode and organic The hole suppression layer, the electron transport layer, and the electron injection layer are disposed between the upper electrodes, but may be disposed inversely between the emission layers.

3 is a cross-sectional view schematically illustrating a structure of a stacked organic electroluminescent device according to another embodiment of the present invention.

Referring to FIG. 3, the stacked organic electroluminescent device of this embodiment includes at least three independently driveable organic electroluminescent device elements. This is because the organic electroluminescent device according to the embodiment of the present invention is for achieving full color.

The stacked organic electroluminescent element according to this embodiment includes a first organic electroluminescent element element 100, a second organic electroluminescent element element 200, and a third organic electroluminescent element element 300.

The first organic electroluminescent element 100 has a first electrode 12 on the first substrate 10. A first organic emission layer 16 is formed on the first electrode, and a second electrode is provided on the first organic emission layer 16. Therefore, in the present exemplary embodiment, since the pixel area is not defined as a partial pixel of R, G, and B on the substrate by the pixel defining layer PDL, it is necessary to finely pattern the organic light emitting material by forming an organic light emitting layer. none.

Then, the second and third organic EL elements 200 and 300 are formed in the same manner as the first organic EL element 100.

That is, the second substrate 20 is formed on the first organic electroluminescent element 100, and the third electrode 22, the second organic light emitting layer 26, and the second substrate 20 are continuously formed on the second substrate 20. The fourth electrode 28 is formed to form the second organic electroluminescent element 200, and then the third substrate 30 and the fifth electrode 32 on the second organic electroluminescent element 200. And a third organic light emitting layer 36 and a sixth electrode 38, the third organic electroluminescent element 300 being provided.

Meanwhile, in the stacked organic EL device of the present invention, each layer may be sequentially formed, and the first organic EL device element 100, the second organic EL device element 200, and the third organic EL device may be sequentially formed. Element 300 may be fabricated separately and then assembled. The method of assembling the individual monochrome substrates is as follows. The thermosetting epoxy resin is coated on the upper electrode of the first organic electroluminescent element element. The two substrates are aligned by using the alignment marks of the first substrate and the second substrate. Thereafter, the third substrate is aligned by the same method and then cured to form a full color device.

In addition, in the stacked organic EL device of the present invention, only the lowermost layer and the uppermost layer, that is, the lower layer of the first organic EL device 100 and the upper layer of the third organic EL device 300 are encapsulated using the encapsulation substrate. do.

As described above, the stacked organic electroluminescent device according to an embodiment of the present invention includes at least three independent organic electroluminescent device elements, and such independently driveable organic electroluminescent device elements should implement full color. The three organic electroluminescent element elements must implement red, blue and green light emission differently from each other.

Preferably, a green light emitting layer is formed in the lower portion, a red light emitting layer in the middle thereof, and a blue light emitting layer is formed in the upper portion based on the light extraction direction.

Therefore, if the present invention is a stacked organic electroluminescent device having a top emission structure, the first organic electroluminescent element 100 realizes green light emission, the second organic electroluminescent element 200 implements red light emission, The third organic electroluminescent element 300 implements blue light emission.

That is, the first organic light emitting layer 16 is formed of a green light emitting material, the second organic light emitting layer 26 is formed of a red light emitting material, and the third organic light emitting layer 36 is formed of a blue light emitting material. The green, red, and blue organic light emitting materials are organic light emitting materials that are commonly used, and may be low molecular materials or high molecular materials.

In this case, the first organic electroluminescent element 100 is formed to be reflective because it must reflect light, and the second and third organic electroluminescent elements 200 and 300 should be formed to be transmissive.

Accordingly, the first electrode 12 of the first organic electroluminescent element element 100 is formed of a metal electrode made of Mg alloy or Al alloy as an anode electrode, and includes a reflective film. The second electrode 18 becomes a cathode and is formed of ITO, IZO, or the like, which is a transparent conductive material. Further, the third electrode 22 and the fourth electrode 28 of the second organic electroluminescent element 200 and the fifth electrode 32 and the sixth electrode 38 of the third organic electroluminescent element 300. ) Has a structure of a transmissive organic electroluminescent device by using a transparent conductive material as a cathode electrode and a thin metal film as an anode electrode or adopting a reverse structure thereof.

On the other hand, in the case of the bottom emission structure, unlike the top emission structure, the third organic electroluminescent element 300 implements green light emission, and the second organic electroluminescent element 200 implements red light emission, and the first The organic electroluminescent element element 100 realizes blue light emission.

That is, the third organic light emitting layer 36 is formed of a green light emitting material, the second organic light emitting layer 26 is formed of a red light emitting material, and the first organic light emitting layer 16 is formed of a blue light emitting material. The green, red, and blue organic light emitting materials are organic light emitting materials that are commonly used, and may be low molecular materials or high molecular materials.

In this case, since the third organic electroluminescent element 300 must reflect light, the third organic electroluminescent element 300 is formed to be reflective, and the first and second organic electroluminescent elements 100 and 200 should be formed to be transmissive.

Therefore, the sixth electrode 38 of the third organic electroluminescent element 300 is formed of a metal electrode made of Mg alloy or Al alloy as the anode electrode, and includes a reflective film. The fifth electrode 32 becomes a cathode and is formed of ITO, IZO, or the like, which is a transparent conductive material. Further, the third electrode 22 and the fourth electrode 28 of the second organic electroluminescent element 200 and the first electrode 32 and the second electrode 38 of the first organic electroluminescent element 100. The upper electrode has a structure of a transmissive organic electroluminescent element by using a transparent conductive material as a cathode electrode, and using a thin metal film as an anode electrode or adopting a reverse structure thereof.

Each of the first, second and third organic EL devices may further include one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a hole suppression layer, an electron transport layer, and an electron injection layer, as necessary. have.

Since the first, second and third organic electroluminescent device elements are independent devices that can be driven independently of each other, the hole injection layer, the hole transport layer, and the hole suppression layer to improve luminous efficiency and lifetime characteristics in each configuration. It may include one or more layers of the electron transport layer and the electron injection layer.

The hole injection layer, the hole transport layer, the hole suppression layer, the electron transport layer and the electron injection layer may be used a material commonly used as an organic material, regardless of whether a high molecular material or a low molecular material.

Positioning positions of the hole injection layer, the hole transport layer, the hole suppression layer, the electron transport layer and the electron injection layer are used in the position used in the conventional organic electroluminescent device, for example, the hole injection layer, the hole transport layer is a lower electrode and organic The hole suppression layer, the electron transport layer, and the electron injection layer are disposed between the upper electrodes, but may be disposed inversely between the emission layers.

As described above, in the present invention, since the upper and lower electrodes and the substrate are provided so that they can be driven independently for each of R, G, and B, a fine pattern mask is not required during manufacturing, and the openings are smaller than the substrates having the R, G, and B pixel portions. Up to nine times more, power consumption is also significantly reduced because the required brightness for configuring full-color devices is less, and the amount of current consumed is small. As a result, a device with a long life and high brightness can be configured. In addition, since the pixel portions of R, G, and B are stacked, the device image quality is excellent. Conventional fine patterning can display three times more resolution than single-substrate full-color devices using high-definition masks.

1 is a cross-sectional view schematically showing the structure of a conventional stacked organic electroluminescent device.

2 is a cross-sectional view schematically illustrating a structure of a stacked organic electroluminescent device according to an embodiment of the present invention.

3 is a cross-sectional view schematically illustrating a structure of a stacked organic electroluminescent device according to another embodiment of the present invention.

Claims (19)

A first substrate; A first electrode formed on the first substrate; A first organic light emitting layer formed on the first electrode; And A first organic electroluminescent device element comprising a second electrode formed on the first organic light emitting layer, A second substrate formed on the first organic electroluminescent element element; A third electrode formed on the second substrate; A second organic light emitting layer formed on the third electrode; And A second organic electroluminescent device element comprising a fourth electrode formed on the second organic light emitting layer, A third substrate formed on the second organic electroluminescent element element; A fifth electrode formed on the third substrate; A third organic light emitting layer formed on the fifth electrode; And And a third organic electroluminescent device element comprising a sixth electrode formed on the third organic light emitting layer. The method of claim 1, The laminated organic electroluminescent device of any one of the first organic electroluminescent device element or the third organic electroluminescent device element is a reflective organic electroluminescent device and the other is a transmissive organic electroluminescent device. The method of claim 2, And the second organic electroluminescent element is a transmissive organic electroluminescent element. The method of claim 1, And the pixel regions of the first, second and third organic electroluminescent element elements are separated by a pixel defining layer. The method of claim 4, wherein The organic light emitting device of claim 1, wherein the organic light emitting layers of the first, second and third organic light emitting device elements are formed in a patterned manner. The method of claim 5, The organic light emitting layer of the first organic electroluminescent device element is composed of a green light emitting material, the organic light emitting layer of the second organic electroluminescent device element is composed of a red light emitting material, and the organic light emitting layer of the third organic electroluminescent device element is A stacked organic electroluminescent device composed of a blue light emitting material. The method of claim 1, The organic light emitting device of claim 1, wherein the organic light emitting layers of the first, second and third organic light emitting device elements are stacked over the entire substrate. The method of claim 1, The organic light emitting layer of the first organic electroluminescent device element is composed of a green light emitting material, the organic light emitting layer of the second organic electroluminescent device element is composed of a red light emitting material, and the organic light emitting layer of the third organic electroluminescent device element is A stacked organic electroluminescent device composed of a blue light emitting material. The method of claim 1, The organic light emitting layer of the first organic electroluminescent device element is composed of a red light emitting material, the organic light emitting layer of the second organic electroluminescent device element is composed of a green light emitting material, and the organic light emitting layer of the third organic electroluminescent device element is A stacked organic electroluminescent device composed of a blue light emitting material. The method of claim 1, And the first, second and third organic electroluminescent device elements selectively further comprise at least one of a hole injection layer, a hole transport layer, a hole suppression layer, an electron transport layer and an electron injection layer, respectively. The method of claim 1, The first electrode is an anode, and the second electrode is a cathode. The method of claim 1, The first electrode is a cathode electrode, the second electrode is an anode electrode stacked organic electroluminescent device. The method of claim 1, The third electrode is an anode, and the fourth electrode is a cathode. The method of claim 1, The third electrode is a cathode electrode, the fourth electrode is an anode electrode stacked organic electroluminescent device. The method of claim 1, The fifth electrode is an anode electrode, and the sixth electrode is a cathode electrode. The method of claim 1, The fifth electrode is a cathode electrode, and the sixth electrode is an anode electrode. The method of claim 1, And the second electrode of the first organic electroluminescent element element or the second electrode of the third organic electroluminescent element element further comprises a reflective film. The method of claim 1, And the lower layer of the first organic electroluminescent element and the upper layer of the third organic electroluminescent element are encapsulated with an encapsulation substrate. An organic electroluminescent device comprising a cathode of a second organic electroluminescent element element and a cathode of a third organic electroluminescent element element.