KR20060112965A - Organic electro-luminescence display employing icon part - Google Patents

Abstract

An organic electro-luminescence display having an icon portion is provided to increase manufacturing efficiency by forming a blue light emitting layer on the icon portion and an image portion. An organic electro-luminescence display having an icon portion includes a substrate(300), a first pixel electrode(500), a second pixel electrode(400), an organic light emitting layer(600), and an upper electrode(700). The substrate is divided into an icon portion and an image portion. The first pixel electrode is formed on the image portion on the substrate. The second pixel electrode is formed on the icon portion on the substrate. The organic light emitting layer is formed on the first and second pixel electrodes. The upper electrode is formed as a common layer on the organic light emitting layer. The organic light emitting layer includes a blue light emitting layer, a red light emitting layer pattern, and a green light emitting layer pattern. The blue light emitting layer is commonly formed on the first and second pixel electrodes. The red light emitting layer pattern and the green light emitting layer pattern are formed under the blue light emitting layer and on the first pixel electrode.

Description

Organic electroluminescent display employing an icon portion {Organic electro-luminescence display employing icon part}

1 is a photograph showing a display unit of a portable mobile communication device having a conventional icon unit.

2A and 2B are plan views and cross-sectional views for describing an organic light emitting display device having a conventional icon unit.

3A to 3D are diagrams for describing an organic light emitting display device according to a first embodiment of the present invention.

4 is a cross-sectional view of an organic light emitting display device according to a second embodiment of the present invention.

 (Explanation of symbols for main parts of drawing)

100: icon part 200: image part

300 substrate 400 second pixel electrode

500: first pixel electrode 600R: red light emitting layer pattern

600G: green light emitting layer pattern 600B: blue light emitting layer

700: upper electrode

The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device having an icon portion.

Today's organic light emitting display devices are capable of low voltage driving and light weight, have a wide viewing angle and high contrast, and have a fast response speed comparable to that of a CRT. Many of these advantages can be applied to most electronic applications, especially in portable devices such as mobile terminals, navigation, PDAs, camcorders and Palm PCs.

1 is a photograph showing a display unit of a portable mobile communication device having a conventional icon unit.

As shown in FIG. 1, the portable device transmits a brief information of a display, such as power information, reception information, a call, a message, and an alarm information, to an image unit 10 implementing various information and a video according to a user's setting, and a user. It is provided with an icon unit 20 having a variety of icons for. Here, the image unit 10 implements an image or a video in which the image is continuously changed by the user's manipulation, but the icon unit 20 implements the same image in a fixed form. In this case, when the organic light emitting display device is applied to the portable device, the organic light emitting layer positioned in the icon portion which must continuously implement the fixed image may be easily deteriorated. Such deterioration of the organic light emitting layer may not only shorten the life of the device but also cause severe afterimage of the image due to damage of the organic light emitting layer.

2A and 2B are diagrams for describing an organic light emitting display device having a conventional icon unit.

As shown in FIG. 2A, in the organic light emitting display device including the image unit 30 and the icon unit 40, the organic light emitting display device may be disposed on the substrate 60 divided into the image unit 30 and the icon unit 40. The first pixel electrode 31 and the second pixel electrode 41 are each patterned.

As described above, in providing the fixed image, the icon part 40 has a problem that an afterimage occurs due to deterioration of the organic layer. To solve this problem, the image unit 30 includes a plurality of unit pixels, while the icon unit 40 is composed of simple pixels in the form of icons. As a result, afterimages caused by deterioration of the organic light emitting layer formed on the icon portion can be suppressed.

The image unit 30 is formed by patterning a first pixel electrode 31 on a plurality of unit pixels. On the other hand, the icon portion 40 is formed of a second pixel electrode 41 patterned in the shape of an icon, for example, as shown in the figure. Here, the shape of the icon depends on the pattern of the second pixel electrode 41.

Subsequently, although not shown in the drawings, an organic light emitting layer is formed on the first pixel electrode 31 and the second pixel electrode 41 and an upper electrode forms an afterimage problem that may occur in the icon unit. An organic electroluminescent display device is solved.

FIG. 2B is a cross-sectional view taken along line II ′ of FIG. 2A, wherein the image unit 30 and the icon unit 40 form a pattern of the organic emission layer 50 through different processes. That is, the substrate 60 divided into the image unit 30 and the icon unit 40 is located, and the first pixel electrode 31 patterned in the image unit 30 and the icon unit 40, respectively; The second pixel electrode 41 is formed. Subsequently, in the case of forming the organic light emitting layer 50 pattern on the first pixel electrode 31 and the second pixel electrode 41 through the same process, a mask for forming the organic light emitting layer 50 pattern The non-emission area B in which the organic emission layer pattern is not formed on the entire surface of the second pixel electrode 41 may occur due to the margin of.

Therefore, conventionally, the organic light emitting layer 50 patterns of the image unit 30 and the icon unit 40 are formed through different processes. As a result, an additional process is required in manufacturing the organic light emitting display device which is divided into the image unit 30 and the icon unit 40. This caused a problem of lowering the productivity and increasing the unit cost of the product.

An object of the present invention is derived to solve the above problems of the prior art, the present invention is to simplify the process by forming an organic light emitting layer through the same process in the image portion and the icon portion, the organic electroluminescence having improved image quality Provided is a display device.

In order to achieve the above technical problem, an aspect of the present invention provides an organic light emitting display device.

In the organic light emitting display device, a substrate divided into an image unit and an icon unit is positioned. A first pixel electrode and a second pixel electrode are positioned in the image portion and the icon portion, respectively. An organic emission layer is disposed on the first pixel electrode and the second pixel electrode. An upper electrode is formed on the organic light emitting layer as a common layer.

The organic light emitting layer may include a blue light emitting layer formed as a common layer on the first pixel electrode and the second pixel electrode, and a red light emitting layer and a green light emitting layer may be formed on the first pixel electrode, respectively, under the blue light emitting layer. .

The organic light emitting layer formed on the second pixel electrode may be formed by patterning a red light emitting layer and a green light emitting layer under the blue light emitting layer.

The red light emitting layer pattern and the green light emitting layer pattern may be made of a phosphorescent light emitting material, and the blue light emitting layer may be made of a fluorescent light emitting material.

In addition, the blue light emitting layer preferably has a thickness of 500 mW or less.

In addition, the blue light emitting layer may be formed by spin coating, inkjet printing, or vacuum deposition.

Hereinafter, an organic light emitting display device according to the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided as examples to sufficiently convey the spirit of the present invention to those skilled in the art. Accordingly, the invention is not limited to the embodiments described below and may be embodied in other forms. In the drawings, the size and thickness of the device may be exaggerated for convenience. Like numbers refer to like elements throughout.

3A to 3D are diagrams for describing an organic light emitting display device according to a first embodiment of the present invention. Here, the display unit provided in the portable mobile communication device will be described, but is not limited thereto. The display unit of the present invention may be applied to various portable displays.

3A is a photograph showing a display unit of a portable mobile communication device. Referring to FIG. 3A, the display unit is divided into an icon unit 100 and an image unit 200. Here, the icon unit 100 includes various icons 110 to deliver power information, reception information, calls, messages, and alarm information to the user. On the other hand, the image unit 200 implements a variety of information and video according to the user's settings.

3B is a plan view schematically illustrating the inside of FIG. 3A. First, a substrate 300 divided into the image unit 200 and the icon unit 100 is positioned. The image unit 200 includes a first pixel electrode 500, and the icon unit 100 includes a second pixel electrode 400.

Here, the icons 110 implement a fixed image, while the image unit 200 implements an image and a video in which the images continuously move. In this case, the icon 110 may be formed of one pixel rather than a plurality of unit pixels in providing a fixed image. That is, one icon is made larger than the pixels of the branch.

Thus, the shape of the pixel electrode formed on the image unit 200 and the icon unit 100 may be different. The first pixel electrode 500 is formed by patterning unit pixel electrodes on each unit pixel. In this case, the first pixel electrode 500 may have a dot shape as shown in the drawing, and is not limited thereto. The first pixel electrode 500 may have various shapes such as a stripe shape and a delta shape. In contrast, the second pixel electrode 400 is formed by patterning each icon.

3C is a cross-sectional view taken along the line II ′ of FIG. 3B, and illustrates an organic light emitting display device according to a first embodiment of the present invention in more detail.

As shown in FIG. 3C, the substrate 300 divided into the image unit 200 and the icon unit 100 is positioned. In the icon unit 100, a second pixel electrode 400 having an icon shape is positioned. On the other hand, the image unit 200 is formed with a first pixel electrode 500 made of a unit pixel electrode formed in a plurality of unit pixel areas, respectively. In this case, the first pixel electrode 500 and the second pixel electrode 400 may be formed of a transparent electrode made of ITO or IZO or a reflective electrode made of metal.

A pixel defining layer 550 having an opening exposing a predetermined portion of each of the unit pixels of the first pixel electrode 500 and the second pixel electrode 400 is positioned.

Subsequently, the organic light emitting layer 600 is positioned on the first pixel electrode 500 and the second pixel electrode 400 exposed through the opening. In this case, the organic light emitting layer includes a red light emitting layer pattern 600R positioned in a red unit pixel region on the first pixel electrode 500, a green light emitting layer pattern 600G positioned in a green unit pixel region, and a first pixel electrode 500. And a blue light emitting layer 600B formed as a common layer on the entire surface of the substrate including the second pixel electrode 400.

The blue light emitting layer 600B may be stacked on the red light emitting layer pattern 600R and the green light emitting layer pattern 600G. Here, the red light emitting layer pattern 600R and the green light emitting layer pattern 600G may be made of a phosphorescent light emitting material having excellent luminous efficiency and color purity. In this case, since the movement speed of the holes is faster than the electrons due to the nature of the phosphorescent light emitting material, the electrons and holes may be combined in the electron transport layer to reduce the luminous efficiency. Accordingly, in the organic light emitting display device made of a phosphorescent light emitting material, a hole suppression layer is additionally required on the organic light emitting layer. However, when the blue light emitting layer 600B made of the fluorescent light emitting material is laminated and formed on the red light emitting layer pattern 600R and the green light emitting layer pattern 600G, respectively, the blue light emitting layer in the red light emitting region and the green light emitting region. Since it does not emit light, the hole suppression layer can be replaced without inferior color purity and color reproducibility due to mixed color.

However, the blue light emitting layer 600B needs to optimize the thickness of the blue light emitting layer in order to have color coordinates and efficiency of each unit pixel. Accordingly, the blue light emitting layer 600B may have a thickness of 500 kW or less in consideration of driving voltages and color coordinates of the red and green unit pixels.

In addition, the red light emitting layer pattern 600R and the green light emitting layer pattern 600G may be patterned and formed by vacuum deposition, inkjet printing, or laser thermal transfer using a shadow mask. On the other hand, since the blue light emitting layer 600B does not need to be patterned, the blue light emitting layer 600B may be formed through an easy process by vacuum deposition, spin coating, or inkjet printing without using a shadow mask.

As a result, the blue light emitting layer 600B is formed on the first pixel electrode as a common layer, thereby reducing the pattern process through the mask and further eliminating the hole suppression layer. At the same time, by forming the blue light emitting layer 600B on the entire surface of the second pixel electrode 400, it is possible to prevent the non-light emitting region from being formed in the light emitting region of the icon due to the margin of the mask as described above. . In addition, since the blue light emitting layer is formed on the entire surface of the substrate on the first pixel electrode 500 and the second pixel electrode 400, the organic light emitting layer 600 is formed on the icon unit 100 and the image unit 200. Since it is not formed through another process, the process can be further simplified.

In addition, the organic light emitting layer 600 may further include at least one functional organic layer. For example, the functional organic layer may include a hole injection layer (HIL) for injecting holes, a hole transport layer (HTL) for increasing hole and electron recombination opportunities by suppressing movement of electrons not bonded in the organic light emitting layer. ), An electron transport layer (ETL) for smoothly transporting electrons to the organic emission layer 600, and an electron injection layer (EIL) for injecting electrons. At this time, the material and the manufacturing method of each layer constituting the organic light emitting layer and the functional organic layer is in accordance with the conventional materials and methods in the art.

Thereafter, the upper electrode 700 is positioned on the organic light emitting layer 600. An encapsulation substrate 800 is disposed on the upper electrode 700 to protect the device by external moisture.

In this case, the image unit 200 may be an active matrix organic electroluminescent device which may not only reduce power consumption but also facilitate implementation of a large area since power consumption may increase when driving a plurality of unit pixels. That is, the image unit may further include a switching thin film transistor, a driving thin film transistor, and a capacitor in each unit pixel.

FIG. 3D is a diagram illustrating the P region of FIG. 3C in more detail, in which one unit pixel including a thin film transistor and a capacitor is defined, that is, a unit pixel P emitting green light.

Referring to FIG. 3D, the substrate 300 is positioned, and the thin film transistor Tr and the capacitor Cp are positioned on the substrate 300. In more detail, a buffer layer 310 may be further provided on the substrate 300 to prevent impurities flowing out from the substrate 300. The semiconductor layer 320 made of a polysilicon layer is disposed on the buffer layer 310.

A gate insulating layer 330 is positioned on the semiconductor layer 320, and a gate electrode 340 is positioned in a predetermined region of the semiconductor layer 320 on the gate insulating layer 330, and the gate electrode 340 is located on the gate insulating layer 330. The capacitor lower electrode 350 is positioned in an area spaced from the capacitor.

An interlayer insulating layer 360 is disposed over the entire surface of the substrate including the upper portion of the gate electrode 340 and the capacitor lower electrode 350. A thin film transistor Tr is formed by source / drain electrodes 370b and 370a positioned in a predetermined region corresponding to the semiconductor layer 320 on the interlayer insulating layer 360, and a predetermined region corresponding to the capacitor lower electrode. A capacitor Cp in which the capacitor upper electrode 380 is positioned is formed.

The passivation layer 390 may be disposed on the thin film transistor Tr and the capacitor Cp. The passivation layer 390 may be made of an inorganic material. For example, the passivation layer 390 may be made of one material selected from a silicon oxide layer, a silicon nitride layer, and a stacked layer of a silicon oxide layer / silicon nitride layer.

The planarization layer 395 may be disposed on the passivation layer 390 to overcome the step difference caused by the thin film transistor Tr and the capacitor Cp.

Alternatively, a planarization layer that may function as a protection layer without forming the protection layer 390 may be formed over the entire surface of the substrate including the thin film transistor Tr and the capacitor Cp.

The planarization layer 395 may be formed of an organic or inorganic material.

A first pixel electrode 400 is electrically connected to the drain electrode 370a of the thin film transistor through a via hole formed in a portion of the passivation layer 390 and / or the planarization layer 395.

The pixel defining layer 550 is disposed on the first pixel electrode 400 and has an opening that exposes a predetermined portion of the first pixel electrode 400.

The organic emission layer 600 is positioned on the first pixel electrode 400 exposed through the opening. In this case, as shown in the drawing, the green light emitting layer pattern 600G is positioned on the first pixel electrode 400, and the blue light emitting layer 600 covers the entire surface of the substrate including the green light emitting layer pattern 600G. 600B) is located.

Subsequently, an upper electrode 700 is positioned on the organic emission layer 600.

4 is a cross-sectional view of an organic light emitting display device according to a second embodiment of the present invention. Here, except that the red light emitting layer pattern 600R 'and the green light emitting layer pattern 600G' are formed on the second pixel electrode 400, they have the same components as those of the first embodiment and are represented by the same reference numerals. Repeated description is omitted.

As shown in FIG. 4, a red emission layer pattern 600R ′ and a green emission layer pattern 600G ′ are positioned on the second pixel electrode 400. Thereafter, the blue light emitting layer 600B is positioned as a common layer on the red light emitting layer pattern 600R 'and the green light emitting layer pattern 600G'. In this case, the blue light emitting layer 600B is connected to and formed on the first pixel electrode 500. Thus, icons located in the icon unit 100 may be implemented in white. In addition, since the blue light emitting layer 600B is formed as a common layer, the non-light emitting region is not formed in the icon unit 100.

In this case, the red light emitting layer pattern 600R 'and the green light emitting layer pattern 600G' of the icon unit 100 are simultaneously formed when the red light emitting layer pattern 600R and the green light emitting layer pattern 600G of the image unit 200 are formed. Can be. Thus, icons located in the icon unit 100 may be implemented in white.

As described above, according to the present invention, in the organic electroluminescent display device which can improve the problem of the afterimage of the icon portion, by forming a blue light emitting layer as a common layer on the icon portion and the image portion, an easier process than before. By manufacturing through, productivity can be increased.

Although the above has been described with reference to a preferred embodiment of the present invention, those skilled in the art will be able to variously modify and change the present invention without departing from the spirit and scope of the invention as set forth in the claims below. It will be appreciated.

Claims (5)

A substrate divided into an image portion and an icon portion; A first pixel electrode formed on the image portion on the substrate; A second pixel electrode formed on the icon portion on the substrate; An organic light emitting layer on the first pixel electrode and the second pixel electrode; An upper electrode formed as a common layer on the organic light emitting layer, The organic light emitting layer includes a blue light emitting layer formed as a common layer on the first pixel electrode and the second pixel electrode, and a red light emitting layer pattern and a green light emitting layer pattern formed under the blue light emitting layer on the first pixel electrode. An organic light emitting display device having an icon portion. The method of claim 1, And an organic light emitting layer formed on the second pixel electrode further comprising a red light emitting layer pattern and a green light emitting layer pattern formed under the blue light emitting layer. The method of claim 1, The red light emitting layer pattern and the green light emitting layer pattern may be formed of a phosphorescent light emitting material, and the blue light emitting layer may be formed of a fluorescent light emitting material. The method of claim 1, And the blue light emitting layer has a thickness of 500 mW or less. The method of claim 1, And the blue light emitting layer is formed by spin coating, inkjet printing, or vacuum deposition.

Images