KR20070031707A - Organic Electro Luminescence Display Device - Google Patents

Abstract

An organic electroluminescent display device in which light emission areas of R, G, and B subpixels are tuned is disclosed. That is, in the organic electroluminescent display, the R, G, and B subpixels are divided by dividing the light emitting areas of the R subpixels and the G subpixels within the range not exceeding the light emitting regions of the B subpixels present in each pixel. The light emission lifespan is matched, and the visibility due to the improvement of the aperture ratio and the dark spot phenomenon due to the inoperability of each R, G, and B subpixels are prevented.

Red subpixel, green subpixel, blue subpixel

Description

Organic Electro Luminescence Display Device

1 is a plan view illustrating pixels of an organic light emitting display device according to the related art.

2 is a plan view illustrating pixels of an organic light emitting display device according to an exemplary embodiment of the present invention.

3 is a diagram illustrating R subpixels, B subpixels, and G subpixels configured in each pixel according to an exemplary embodiment of the present invention, cut along a predetermined axis, as shown in FIGS. 3A, 3B, and 3C.

The present invention relates to an organic electroluminescent display, and more particularly, the light emitting areas of each R and G subpixels are divided and arranged within the range not exceeding the light emitting regions of the B subpixels present in each pixel. The present invention relates to an organic electroluminescent display that matches the light emission life of R, G, and B subpixels, and prevents visibility due to improvement in aperture ratio and dark spots due to the inoperability of each R, G, and B subpixels.

In general, an organic electroluminescent display is a flat self-emission display that emits light by applying an electric field to a phosphor coated on a glass substrate or a transparent organic film. Electroluminescence refers to a phenomenon of emitting light when an electric field is applied to a phosphor made of a semiconductor.

Recently, liquid crystal display LCDs and organic EL display OLEDs have been used for portable information devices due to their light weight and thinness. Organic electroluminescent display devices are attracting attention as next-generation flat panel display devices because they have better luminance and viewing angle characteristics than liquid crystal displays.

Typically, pixels formed in the active matrix organic electroluminescent display AMOLED are composed of R, G, and B subpixels, and each of the R, G, and B subpixels includes an organic electroluminescent display element. Each organic electroluminescent display device is formed from an organic film formed of an R, G, B organic light emitting layer by a voltage applied to the anode electrode and the cathode electrode through each R, G, B organic light emitting layer between the anode electrode and the cathode electrode. Emits light.

In addition, the active matrix organic EL display device AMOLED drives the N * M organic electroluminescent display elements by using a voltage programming method or a current programming method.

1 is a plan view illustrating pixels of an organic light emitting display device according to the related art.

Referring to FIG. 1, a pixel formed in an organic light emitting display device includes R (Red: 100), G (Green: 110), and B (Blue: 120) subpixels, respectively. Among the R subpixel 100, the G subpixel 120, and the B subpixel 130, the subpixel having the shortest light emission lifetime is the B subpixel 120, followed by the G subpixel 110. The R subpixel 100 has the longest light emission life. Accordingly, the light emitting area of the B subpixel 120 is the largest, the light emitting area of the G subpixel 110 is next, and the light emitting area of the R subpixel 100 is the smallest. The R, G, and B subpixels 100, 110, and 120 each have a light emission area of the R, G, and B sub-pixels, based on the B subpixel 120, so that the light emission lifetimes of the R, G, and B are matched. It is formed by decreasing a predetermined area in order of the R subpixel 100.

The problems associated with the pixels of the conventional organic electroluminescent display device related to the present invention and solved by the present invention are as follows.

The pixel formed in the organic electroluminescent display reduces the light emitting area of the G subpixel and the light emitting area of the R subpixel based on the light emitting area of the B subpixel to match the light emission lifetime of each of the R, G, and B subpixels. As a result, the opening ratio of the R subpixel and the opening ratio of the G subpixel are lowered, thereby reducing visibility, and there is a problem in that dark spots are generated due to the failure of any one of the subpixels of the R, G, and B subpixels.

An object of the present invention is to divide each of the R and G subpixels by dividing the light emitting areas of each of the R and G subpixels within a range not exceeding the light emitting region of the B subpixel present in each pixel of the organic electroluminescent display. To match the light emission life of the B subpixel, and to prevent visibility due to improvement of the aperture ratio and to prevent dark spots caused by the inoperability of each of the R, G, and B subpixels.

An organic electroluminescent display device having an active circuit for controlling light emission of each subpixel, comprising: a blue subpixel in which blue light is displayed through a first light emitting area formed in a predetermined light emitting area; A green subpixel displaying green light through a second light emitting area smaller than the first light emitting area; And a red subpixel in which red light is displayed through a third light emitting area smaller than the second light emitting area.

And a pixel in which the second light emitting area of the green subpixel is divided into a plurality of parts and dividedly arranged within a range not exceeding the light emitting area of the red subpixel, and the third light emitting area of the red subpixel is divided into a plurality of parts. An organic electroluminescent display is provided.

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

Example

2 is a plan view illustrating pixels of an organic light emitting display device according to an exemplary embodiment of the present invention.

Referring to FIG. 2, each pixel formed in the organic electroluminescent display includes R (Red: 200), G (Green: 210), and B (Blue: 220) subpixels, respectively. Due to the characteristics of the G and B elements, the light emission lifetime is different.

That is, among the R subpixel 200, the G subpixel 210, and the B subpixel 220, the subpixel having the shortest light emission life is the B subpixel 220, and then the G subpixel 210. ) And the R subpixel 200 has the longest light emission life. Accordingly, the light emitting area of the B subpixel 220 is largest, the light emitting area of the G subpixel 210 is next divided, and the light emitting area of the R subpixel 200 is designed to be the smallest. In other words, since the light emission lifetimes of the R subpixels 200, G subpixels 210, and B subpixels 220 are different from each other, the emission region and the G subpixels 210 of the R subpixel 200 are different from each other. The light emitting regions of the R subpixels 200 and G subpixels 210 are formed by dividing the light emitting regions of the B subpixels 220 in a range not exceeding a predetermined light emitting region of the B subpixels 220.

That is, since the light emitting areas of the R subpixel 200, the G subpixel 210, and the B subpixel 220 are divided into various places within the range not departing from the light emitting region of the B subpixel 220. Accordingly, the light emission lifetime of each R subpixel 200, the light emission lifetime of the G subpixel 210, and the light emission lifetime of the B subpixel 220 coincide with each other.

3 is a diagram illustrating R subpixels, B subpixels, and G subpixels configured in each pixel according to an exemplary embodiment of the present invention, cut along a predetermined axis, as shown in FIGS. 3A, 3B, and 3C.

The organic electroluminescent display according to the present invention is driven in an active matrix manner according to the operation of a thin film transistor that is already disposed.

First, the manufacturing process formed according to an embodiment of the present invention includes a substrate made of glass, synthetic resin, and the like, and to prevent impurities flowing out of the upper portion of the silicon oxide film, silicon nitride film, and silicon oxide film / nitride film (SiO 2 / SiNx). Select one of the laminated films to form a buffer layer.

However, the buffer layer is not necessarily formed, it is preferable to form selectively.

Next, after the amorphous silicon film is coated and crystallized over the entire surface of the substrate to form a polysilicon film, the polysilicon film is patterned so that the semiconductor layer pattern is provided on the thin film transistor and the gate insulating film is formed on the entire surface of the substrate. do.

Next, a metal layer pattern is formed by depositing and patterning a gate electrode material on the gate insulating layer so as to correspond to the channel region of the semiconductor layer pattern defined in the thin film transistor unit, and using the metal layer pattern as a mask to form a metal layer pattern. By ion doping the semiconductor layer pattern, a source region and a drain region are defined.

The gate electrode material may be formed of at least one metal material among alloys including metal materials such as chromium (Cr), molybdenum (Mo), aluminum (Al), or silver (Ag).

Next, an interlayer insulating film is formed over the entire surface of the substrate, and a contact hole is formed in the thin film transistor portion so that a predetermined portion of the source region and the drain region of the semiconductor layer pattern are exposed.

Next, a source / drain electrode is formed by depositing and patterning a source / drain electrode material so that the upper portion of the interlayer insulating layer and the source / drain region of the semiconductor layer pattern are connected through the contact hole in the thin film transistor.

Here, the source / drain electrode material is made of at least one metal material among alloys including metal materials such as tungsten (W), molybdenum (Mo), aluminum (Al) or silver (Ag).

Next, a passivation film 290 is formed by selecting one of a silicon oxide film (SiO 2), a silicon nitride film (SiNx), and a stacked film over the entire surface of the substrate including the thin film transistor unit. In addition, a planarization film, which is at least one organic film among an acrylic resin, a benzocyclobutene resin (BCB), a polyimide resin (PI), a spin on glass (SOG), an acrylate (Acrylate), or a polyphenol resin, may be formed on the passivation layer. Form.

Next, the planarization layer and the passivation layer formed on the thin film transistor are collectively etched to form a via hole 310 to expose a portion of the source / drain electrode, and patterned to be connected to the source / drain electrode through the via hole. 1 electrode is formed.

FIG. 3A is a diagram illustrating an R subpixel formed in a pixel cut into l−1 ′ to form a first thin film transistor portion A, and includes a first opening 320, a second opening 330, and a third opening 340. The cross-sectional view is shown so that the entire surface through the light emitting.

Referring to FIG. 3A, in an organic electroluminescent display device having a plurality of pixels formed such that the light emitting region of the R subpixel and the light emitting region of the G subpixel do not exceed the light emitting region of the B subpixel, the R subpixel may include a plurality of pixels. After applying the first pixel defining layer 310, which is used as the pixel isolation layer, over the entire surface of the substrate on which the first anode electrode 300, which is the first electrode, is formed, is patterned to form an upper surface of the first anode electrode 300. The first opening part 320, the second opening part 330, and the third opening part 340 are formed to expose part of the first opening part 320.

That is, the first opening 320, the second opening 330, and the third opening 340 all have the same opening range, and various shapes are formed by etching the first pixel defining layer 310 in a predetermined pattern. An opening having is formed.

Next, the R subpixel includes a first organic layer including a red light emitting layer on the first anode electrode 320 exposed in the first opening 320, the second opening 330, and the third opening 340. To form 350. Accordingly, the organic layer 350 may include the first anode electrode 300 and the first pixel defining layer 310 exposed in the first opening 320, the second opening 330, and the third opening 340. The gate electrode material or the source / drain electrode material is pattern-masked thereon, and is deposited to not exceed the light emitting region of the B subpixel.

In addition, the R subpixel may include tungsten (W), chromium (Cr), molybdenum (Mo), aluminum (Al), or silver (Ag) on the first anode electrode 300 and the first pixel defining layer 310. The first organic layer 350 is formed over the entire surface of the substrate by disposing a pattern mask formed of at least one metal material among an alloy including a metal material.

Here, a process technique of forming a pattern mask from the metal material to deposit a predetermined organic material or inorganic material is called a fine metal mask (FMM).

Next, the first cathode electrode 360, which is a second electrode, is disposed on the first organic layer 350 and the first pixel defining layer 310 through the FMM within a range not leaving the emission region of the B subpixel through the FMM. And is deposited over the entire surface of the substrate, including the top.

Here, the material forming the first anode electrode 300 is a transparent electrode of ITO or IZO, the material forming the first cathode electrode 360 is a metal material such as magnesium (Mg), silver (Ag) It consists of at least one metallic material among the alloys (ally) it contains.

The first pixel defining layer 310 may include at least one of an acrylic resin, a benzocyclobutene resin (BCB), a polyimide resin (PI), a spin on glass (SOG), an acrylate (acrylate), or a polyphenol resin. Made of organic materials.

FIG. 3B is a view showing a G subpixel formed in a pixel cut in m-m 'to form a second thin film transistor portion B, and to emit light through the first opening 420 and the second opening 430. One cross section.

Referring to FIG. 3B, in the organic electroluminescent display device including a plurality of pixels formed such that the light emitting region of the R subpixel and the light emitting region of the G subpixel do not exceed the light emitting region of the B subpixel, the G subpixel is configured as follows. The second pixel defining layer 410 used as the pixel isolation layer is applied over the entire surface of the substrate on which the second anode electrode 400 is formed, and then patterned to form an upper surface of the second anode electrode 400. The first opening 420 and the second opening 430 are formed to expose a portion thereof.

That is, the first opening 420 and the second opening 430 both have the same opening range, and the openings having various shapes are formed by etching the first pixel defining layer 410 in a predetermined pattern.

Next, the G subpixel forms a second organic layer 440 including a green light emitting layer on the second anode electrode 400 exposed in the first opening 420 and the second opening 430. Accordingly, the second organic layer 440 is disposed on the second anode electrode 400 and the second pixel defining layer 410 exposed in the first opening 420 and the second opening 430. A pattern mask is formed on the material or the source / drain electrode material so as not to exceed the light emitting region of the B subpixel.

In addition, the G subpixel may include tungsten (W), chromium (Cr), molybdenum (Mo), aluminum (Al), or silver (Ag) on the second anode electrode 400 and the second pixel defining layer 410. The second organic layer 440 is formed over the entire surface of the substrate by disposing a pattern mask formed of at least one metal material among an alloy including a metal material.

Here, a process technique of forming a pattern mask from the metal material to deposit a predetermined organic material or inorganic material is called a fine metal mask (FMM).

Next, the second cathode electrode 450, which is a second electrode, passes through the second organic layer 440 and the second pixel defining layer through the FMM within a range not leaving the emission region of the B subpixel through the FMM. 410 is formed over the entire surface of the substrate including an upper portion.

Here, the material forming the second anode electrode 400 is a transparent electrode of ITO or IZO, the material forming the second cathode electrode 450 is a metal material such as magnesium (Mg), silver (Ag) It is made of at least one metal material among the alloy (ally) comprising a.

The second pixel defining layer 410 may include at least one of an acrylic resin, a benzocyclobutene resin (BCB), a polyimide resin (PI), a spin on glass (SOG), an acrylate (acrylate), or a polyphenol resin. Made of organic materials.

FIG. 3C is a cross-sectional view of the B subpixel configured in the pixel as n-n 'to form a third thin film transistor portion C, and emit light at full surface through a predetermined opening 520.

Referring to FIG. 3C, in the organic electroluminescent display device including a plurality of pixels formed such that the light emitting region of the R subpixel and the light emitting region of the G subpixel do not exceed the light emitting region of the B subpixel, the B subpixel may include a plurality of pixels. A third pixel defining layer 510, which is used as a pixel isolation layer, is coated over the entire surface of the substrate on which the third anode electrode 500, which is the first electrode, is formed, and then patterned to form an upper surface of the third anode electrode 500. The opening 520 is formed to expose a part of the opening.

That is, all of the openings 520 have the same opening range, and the openings having various shapes are formed by etching the third pixel defining layer 510 in a predetermined pattern.

Next, the sub-pixel B forms a third organic layer 530 including a blue light emitting layer on the third anode electrode 500 exposed in the opening 520. Accordingly, the third organic layer 530 may include the gate electrode material or the source / drain electrode material on the third anode electrode 500 and the third pixel defining layer 510 exposed in the opening 520. It is formed by depositing a pattern mask so as not to exceed a predetermined light emitting area.

In addition, the B subpixel may include tungsten (W), chromium (Cr), molybdenum (Mo), aluminum (Al), or silver (Ag) on the third anode electrode 500 and the third pixel defining layer 510. The third organic layer 530 is formed over the entire surface of the substrate by disposing a pattern mask formed of at least one metal material in an alloy including a metal material.

Here, a process technique of forming a pattern mask from the metal material to deposit a predetermined organic material or inorganic material is called a fine metal mask (FMM).

Next, the third cathode electrode 540, which is a second electrode, has the third organic layer 530 and the third pixel defining layer 510 through the FMM within a range not leaving the predetermined emission region through the FMM. It is deposited and formed over the entire surface of the substrate including the top.

Here, the material forming the third anode electrode 500 is a transparent electrode of ITO or IZO, the material forming the third cathode electrode 540 is a metal material such as magnesium (Mg), silver (Ag) It consists of at least one metallic material among the alloys (ally) it contains.

The third pixel defining layer 510 may include at least one of an acrylic resin, a benzocyclobutene resin (BCB), a polyimide resin (PI), a spin on glass (SOG), an acrylate (acrylate), or a polyphenol resin. Made of organic materials.

In the exemplary embodiment of the present invention, the openings formed in the R subpixel are limited to three openings, the openings formed in the G subpixel, and the openings formed in the B subpixel are limited to one, but the present invention is not limited thereto. Note that three or more openings, two or more openings of the G subpixel, and one or more openings of the B subpixel may be formed.

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 described in the claims below. It will be appreciated.

According to the present invention described above, the organic electroluminescent display device divides the light emitting area of each of the R and G subpixels in a range not exceeding the light emitting region of the B subpixel present in each pixel, thereby dividing and arranging each of the R and G subpixels. , The light emission life of the B subpixel is matched, and the visibility is improved due to the improvement of the aperture ratio, and the effect of preventing dark spots due to the inoperability of each of the R, G, and B subpixels.

Claims (11)

An organic electroluminescent display device having an active circuit for controlling light emission of each subpixel, A blue subpixel in which blue light is displayed through a first light emitting area formed in a predetermined light emitting area; A green subpixel displaying green light through a second light emitting area smaller than the first light emitting area; And A red subpixel displaying red light through a third light emitting area smaller than the second light emitting area, And a pixel in which the second light emitting area of the green subpixel is divided into a plurality of parts and dividedly arranged within a range not exceeding the light emitting area of the red subpixel, and the third light emitting area of the red subpixel is divided into a plurality of parts. Organic electroluminescent display. The method of claim 1, wherein the red subpixel, Board; A first thin film transistor unit formed on the substrate; A first passivation film formed over an entire surface of the substrate including an upper portion of the first thin film transistor portion; A first anode electrode connected to any one of a source / drain electrode formed in the first thin film transistor portion through a via hole passing through the first passivation layer; A first pixel defining layer having three or more openings through which a portion of the first anode electrode is exposed; A first organic layer formed of a red light emitting layer over an entire surface of the substrate including an upper portion of the first anode electrode exposed to the three or more openings; And And a red subpixel formed of a first cathode electrode formed over an entire surface of the substrate including an upper portion of the first organic layer. The organic electroluminescent display device according to claim 2, wherein the three or more openings have substantially the same shape. The organic light emitting display device of claim 3, wherein the first organic layer is formed using a pattern mask disposed on the first anode electrode and the first pixel defining layer. The method of claim 1, wherein the green subpixel, Board; A second thin film transistor unit formed on the substrate; A second passivation film formed over an entire surface of the substrate including an upper portion of the second thin film transistor portion; A second anode electrode connected to any one of a source / drain electrode formed on the second thin film transistor through a via hole penetrating the second passivation layer; A second pixel defining layer forming two or more openings to expose a portion of the second anode electrode; A second organic layer formed of a green light emitting layer over an entire surface of the substrate including an upper portion of the second anode electrode exposed to the at least two openings; And And a green subpixel formed of a second cathode electrode formed over an entire surface of the substrate including an upper portion of the second organic layer. The organic light emitting display device of claim 5, wherein the two or more openings have substantially the same shape. The organic light emitting display device of claim 6, wherein the second organic layer is formed using a pattern mask disposed on the second anode electrode and on the second pixel defining layer. The method of claim 1, wherein the blue subpixel, Board; A third thin film transistor unit formed on the substrate; A third passivation film formed over an entire surface of the substrate including an upper portion of the third thin film transistor portion; A third anode electrode connected to any one of source / drain electrodes formed on the third thin film transistor through a via hole penetrating the third passivation layer; A third pixel defining layer forming a predetermined opening so that a portion of the third anode electrode is exposed; A third organic layer formed of a blue light emitting layer over an entire surface of the substrate including an upper portion of the third anode electrode exposed through the opening; And And a blue subpixel formed of a third cathode electrode formed over an entire surface of the substrate including an upper portion of the third organic layer. The organic light emitting display device of claim 8, wherein the opening is formed in various shapes by etching the third pixel defining layer in a predetermined pattern. The organic light emitting display device of claim 9, wherein the third organic layer is formed using a pattern mask disposed on the third anode electrode and on the third pixel defining layer. The alloy of claim 4, 7 or 10, wherein the pattern mask comprises a metal material such as tungsten (W), chromium (Cr), molybdenum (Mo), aluminum (Al) or silver (Ag). and at least one metallic material among (ally).

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