JP2007095405A - Organic el display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow efficient light emission by suppressing increase in electric resistance of a wiring even if a plurality of display regions are formed. <P>SOLUTION: An organic EL display comprises display regions 100a and 100b. The organic EL display further comprises a substrate 101, a positive electrode wiring 102 arranged in the display regions 100a and 100b, negative electrode wiring 105 arranged in the display regions 100a and 100b, an organic light emitting layer 107 formed between the positive electrode wiring 102 and negative electrode wiring 105 within the display regions 100a and 100b, and a connection wiring 200 that is formed between the display regions 100a and 100b for connecting the negative electrode wiring 105 in the display regions 100a and 100b, between the display regions 100a and 100b. A surface resistance of the connection wiring 200 is less than that of the negative electrode wiring 105. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic EL display device, and more particularly to an organic EL display device having a plurality of display areas spaced from each other.

  In recent years, an organic EL (Electro Luminescence) display device has attracted attention as an FPD (Flat Panel Display). An organic EL display device is a self-luminous display element, has a wider viewing angle than a liquid crystal display device, and can be thinned because a backlight is not required. In addition, it has a high response speed and is expected as a next-generation display device because of the variety of luminescent properties of organic substances.

In recent years, an organic EL display device that has a plurality of display areas and displays a plurality of information in each of the plurality of display areas at a time has also been proposed.
Patent Document 1 describes an organic EL display device in which a plurality of organic EL display elements are arranged in a matrix. A plurality of display areas are formed by each of the plurality of organic EL display elements.
JP 2005-509904 A

In the technique described in Patent Document 1, a plurality of display regions are formed using a plurality of organic EL display elements. However, in order to reduce manufacturing costs and man-hours, a plurality of organic EL display elements are included in one organic EL display element. Attempts have been made to form display areas.
However, when a plurality of display areas are to be formed in one organic EL display element, for example, a plurality of cathode wirings in the plurality of display areas are newly connected to a plurality of connection wirings respectively connecting the plurality of display areas. There is a need to form. Since this connection wiring is provided between a plurality of display areas, the wiring becomes long as a whole, and the electrical resistance of the wiring is increased. For this reason, there was a problem that the luminance of the organic EL display device could not be obtained sufficiently.

  The present invention has been made in order to solve such problems, and an organic EL display device capable of efficiently emitting light while suppressing an increase in electrical resistance of wiring even when a plurality of display regions are formed. The purpose is to provide.

  An organic EL display device according to the present invention is an organic EL display device having a plurality of display areas spaced apart from each other, and includes a substrate and a first formed on the substrate and disposed in the plurality of display areas. Formed between the wiring, the second wiring formed to intersect the first wiring, and disposed in the plurality of display areas, and the first and second wirings in the plurality of display areas. An organic light emitting layer, and a connection wiring that is formed between the plurality of display areas, and connects one of the first or second wirings in the plurality of display areas between the plurality of display areas; The surface resistance of the connection wiring is smaller than the surface resistance of the first or second wiring to be connected.

  With such a configuration, even when a plurality of display regions are formed, an increase in electrical resistance of wiring can be suppressed and light can be emitted efficiently.

Further, the connection wiring may be a laminate of one of the first or second wirings to be connected and a metal film having a surface resistance smaller than that of the first or second wiring to be connected.
Thus, even when a plurality of display regions are formed, an increase in the electrical resistance of the wiring can be suppressed and light can be emitted efficiently with a simple configuration.

  According to the present invention, even when a plurality of display areas are formed, an increase in electrical resistance of wiring can be suppressed and light can be emitted efficiently.

Embodiment 1 of the Invention
An organic EL display device according to Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the configuration of the organic EL display device according to the first embodiment of the present invention, and is a schematic diagram showing a situation where a substrate is observed from the side where electrodes are formed. 2 is a diagram showing a configuration of the organic EL display device according to the first embodiment of the present invention, and is a cross-sectional view taken along the line XX of FIG. In FIG. 1, the sealing substrate 108 and the water capturing agent 110 are omitted.

As shown in FIGS. 1 and 2, the organic EL element substrate 1000 includes an anode wiring 102 as a first wiring, an insulating film 103, a cathode wiring 105 as a second wiring, and a cathode partition wall 106 on a substrate 101. The organic light emitting layer 107, the low resistance metal film 150, and the like are formed. The organic EL element substrate 1000 is provided with two display areas 100a and 100b that are separated from each other. For example, a gap of 5 mm to 10 mm or more is provided between the display area 100a and the display area 100b.
As shown in FIG. 1, anode wirings 102 are formed in a stripe pattern on a substrate 101. The anode wiring 102 is disposed through the first and second display areas 100a and 100b. For example, a glass substrate is used as the substrate 101. For example, ITO (Indium Tin Oxide) is used as the material of the anode wiring 102.

As shown in FIGS. 1 and 2, an insulating film 103 having an opening 103 a is formed on the anode wiring 102. The opening 103 a is provided at the intersection between the anode wiring 102 and the cathode wiring 105.
As shown in FIGS. 1 and 2, the organic light emitting layer 107 is formed by being laminated on the anode wiring 102. Note that the organic light emitting layer 107 is formed of a laminated body such as a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. In addition, it is not limited to such a structure, It may have a different structure from this.

  As shown in FIGS. 1 and 2, the cathode wiring 105 is formed in a stripe shape substantially orthogonal to the anode wiring 102. The cathode wiring 105 is disposed through the first and second display areas 100a and 100b. As the material of the cathode wiring 105, aluminum or an aluminum alloy is usually used. In addition to Al and Al alloys, alkali metals such as Li, Ag, Ca, Mg, Y, In, and alloys containing these may be used as the material of the cathode wiring 105. The cathode wiring 105 is connected to a cathode auxiliary wiring 105 a arranged on the edge of the substrate 101. The cathode auxiliary wiring 105 a is formed on the substrate 101. Further, the cathode auxiliary wiring 105a is formed by sequentially stacking, for example, a NiMo film, an Al film, and a MoNb film.

As shown in FIGS. 1 and 2, a low resistance metal film 150 is formed between the substrate 101 and the cathode wiring 105 between the first display region 100a and the second display region 100b. The low resistance metal film 150 is formed in close contact with the cathode wiring 105.
Here, as illustrated in FIG. 2, a stacked body of the cathode wiring 105 and the low-resistance metal film 150 between the first display region 100 a and the second display region 100 b is referred to as a connection wiring 200.

The connection wiring 200 is formed between the first display area 100a and the second display area 100b. The cathode wiring 105 in the first display area 100 a and the cathode wiring 105 in the second display area 100 b are electrically connected by the connection wiring 200. The surface resistance of the connection wiring 200 is set to be smaller than the surface resistance of the cathode wiring 105.
As shown in FIGS. 1 and 2, the cathode wiring 105 in the connection wiring 200 is formed integrally with the cathode wiring 105 in the first display area 100a and the second display area 100b.

  The low resistance metal film 150 is formed of a metal material having a surface resistance smaller than that of the cathode wiring 105. In this way, the low-resistance metal film 150 is made of a metal material having a surface resistance smaller than that of the cathode wiring 105, and the cathode wiring 105 is stacked on the low-resistance metal film 150 to form the connection wiring 200. The sheet resistance of the wiring 200 can be made smaller than the sheet resistance of the cathode wiring 105.

The low-resistance metal film 150 can be formed by, for example, a stacked body in which a NiMo film, an Al film, a MoNb film, and a NiMo film are sequentially stacked.
Specifically, when the low-resistance metal film 150 is formed by a stacked body in which a NiMo film with a thickness of 50 nm, an Al film with a thickness of 370 nm, a MoNb film with a thickness of 30 nm, and a NiMo film with a thickness of 50 nm are sequentially stacked, The sheet resistance of the resistive metal film 150 could be about 0.1 ohm (Ω) / □.
On the other hand, when aluminum is used for the cathode wiring 105, the surface resistance of aluminum is about 0.5 ohm (Ω) / □.

  As described above, the sheet resistance of the low resistance metal film 150 can be made smaller than the sheet resistance of the cathode wiring 105. When the width of the low resistance metal film 150 (vertical direction on the paper surface in FIG. 1) is the same as the width of the cathode wiring 105 (vertical direction on the paper surface in FIG. 1), the cathode wiring 105 and the low resistance metal film 150 are stacked. The sheet resistance of the connection wiring 200 which is a body is theoretically (0.1 × 0.5) / (0.1 + 0.5) = about 0.08 ohm (Ω) / □, and the sheet resistance of the connection wiring 200 is Can be made much smaller than the surface resistance of the cathode wiring 105.

As described above, since the plurality of display areas 100a and 100b are formed, it is necessary to add the connection wiring 200 for connecting the plurality of display areas 100a and 100b. By making it smaller than the sheet resistance of 105, an increase in the electrical resistance of the wiring can be suppressed.
Note that the cathode auxiliary wiring 105 a may be a stacked body made of the same material as the low-resistance metal film 150. By doing so, the low-resistance metal film 150 and the cathode auxiliary wiring 105a can be simultaneously formed on the substrate 101 without adding a manufacturing process.

  As shown in FIGS. 1 and 2, the cathode partition 106 is formed on the insulating film 103 so as to be orthogonal to the anode wiring 102. The organic light emitting layer 107, the cathode wiring 105, and the low-resistance metal film 150 are separated using the cathode barrier 106 and a photomask, whereby the organic light emitting layer 107 is formed between the cathode barriers 106, and the striped cathode wiring is formed. 105 is formed, and a low resistance metal film 150 is formed between the first and second display regions 100a and 100b.

At the intersection of the anode wiring 102 and the cathode wiring 105, the anode wiring 102 functions as an anode and the cathode wiring 105 functions as a cathode.
The cross-sectional shape of the cathode partition wall 106 is an inversely tapered shape. By making the cathode partition wall 106 an inversely tapered shape, the side walls and rising portions of the cathode partition wall 106 are shaded, and a plurality of cathode wirings 105 are formed in the manufacturing process. In addition, the low-resistance metal film 150 can be spatially separated. Note that the low-resistance metal film 150 may be formed separately by photoetching.

As shown in FIGS. 2 and 3, the sealing substrate 108 is disposed so as to face the surface of the organic EL element substrate 1000, that is, the surface of the substrate 101 on which the organic light emitting layer 107 and the like are disposed. The organic light emitting layer 107 and the like on 101 are sealed so as to be shielded from the outside air. That is, the sealing substrate 108 and the substrate 101 are bonded together by the sealing material 109 applied to the outer periphery of the sealing substrate 108.
As shown in FIGS. 2 and 3, a water catching agent 110 is applied to the central portion of the sealing substrate 108 on the side facing the substrate 101. Note that a combustion-supporting gas such as oxygen or nitrogen is sealed in a sealing space between the substrate 101 and the sealing substrate 108.

  As described above, the surface resistance of the connection wiring 200 that connects the cathode wiring 105 in the first display area 100a and the second display area 100b between the first and second display areas 100a and 100b is represented by the cathode wiring. By making it smaller than the surface resistance of 105, even if the plurality of display regions 100a and 100b are formed, an increase in the electrical resistance of the wiring can be suppressed, and the light emitting layer in the organic light emitting layer 107 can efficiently emit light. .

Embodiment 2 of the Invention
Next, an organic EL display device according to Embodiment 2 of the present invention will be described with reference to the drawings. FIG. 4 is a diagram showing the configuration of the organic EL display device according to the second embodiment of the present invention, and is a schematic diagram showing a situation where the substrate is observed from the side on which the electrodes are formed. FIG. 5 is a diagram showing the configuration of the organic EL display device according to Embodiment 1 of the present invention, and is a cross-sectional view taken along the line ZZ of FIG. In FIG. 4, the sealing substrate 108 and the water capturing agent 110 are omitted.

  In the first embodiment of the present invention, as shown in FIGS. 1 and 2, the connection wiring 200 is formed between the first and second display regions 100a and 100b, and is connected to the first display region 100a. Whereas the cathode wiring 105 and the cathode wiring 105 in the second display area 100b are connected between the first and second display areas 100a and 100b, in the second embodiment of the present invention, As shown in FIGS. 4 and 5, the connection wiring 200a is formed between the first and second display areas 100c and 100d, and the anode wiring 102 in the first display area 100c and the second display area. The difference is that the anode wiring 102 in the region 100d is connected between the first and second display regions 100c and 100d.

  In the first embodiment of the present invention, as shown in FIG. 2, the low-resistance electric film 150 is between the first and second display regions 100a and 100b, and includes the substrate 101 and the cathode wiring 105. In contrast, in the second embodiment of the present invention, as shown in FIG. 5, the low resistance electric film 150 is provided between the first and second display regions 100c and 100d. The difference is that they are stacked on the anode wiring 102 formed on the substrate 101.

Here, as shown in FIGS. 4 and 5, the connection wiring 200a is configured by a laminate of the anode wiring 102 and the low resistance metal film 150 between the first display region 100c and the second display region 100d. Has been.
The connection wiring 200a is formed between the first display region 100c and the second display region 100d. The anode wiring 102 in the first display area 100c and the anode wiring 102 in the second display area 100d are electrically connected by the connection wiring 200a. The surface resistance of the connection wiring 200 a is set to be smaller than the surface resistance of the anode wiring 102.

As shown in FIGS. 4 and 5, the anode wiring 102 constituting the connection wiring 200a is formed integrally with the anode wiring 102 in the first display area 100c and the second display area 100d.
The low resistance metal film 150 is formed of a metal material having a smaller surface resistance than the anode wiring 102. A metal material having a surface resistance smaller than that of the anode wiring 102 is used for the low resistance metal film 150, and the low resistance metal film 150 is laminated on the anode wiring 102 to form the connection wiring 200a. The resistance can be made smaller than the surface resistance of the anode wiring 102.

  As described above, since the plurality of display areas 100c and 100d are formed, it is necessary to add the connection wiring 200a for connecting the plurality of display areas 100c and 100d. By making it smaller than the surface resistance of 102, an increase in the electrical resistance of the wiring can be suppressed, and the light emitting layer in the organic light emitting layer 107 can emit light efficiently.

Examples of the present invention and conventional examples will be described below.
First, the configuration and dimensions of the organic EL element substrate 1000b used in Examples and Conventional Examples will be described with reference to the drawings. FIG. 6 is a plan view showing the configuration of the organic EL element substrate of the example and the conventional example in the first embodiment of the present invention.

  As shown in FIG. 6, the organic EL element substrate 1000b is provided with three display areas 100e, 100f, and 100g. Although not shown, inside the display areas 100e, 100f, and 100g, as in the case shown in FIGS. 1 and 2, each of the anode wiring 102 and the cathode wiring 105 is substantially orthogonal to each other. It is formed in a stripe shape. At this time, an organic light emitting layer 107 is formed between the anode wiring 102 and the cathode wiring 105. In addition, the distance between the wiring centers of the anode wiring 102 and the cathode wiring 105 in each of the display areas 100e, 100f, and 100g is set to 0.35 mm, and the width of each wiring 102 and 105 is set to 0.33 mm.

  The external dimensions of the organic EL element substrate 1000b are set to a = 85.6 mm and b = 18.3 mm. The external dimensions of the display areas 100e and 100g are set to d = h = 16.1 mm and j = 9.1 mm, and the external dimensions of the display area 100f are f = 12.6 mm and j = 9.1 mm. Is set to Further, the gaps e and g between the display area 100e and the display area 100f are set to e = g = 16.0 mm. As other dimensions, c = 4.4 mm, i = 5.4 mm, and k = 76.8 mm. It is assumed that the cathode auxiliary wiring 105a shown in FIGS. 1 and 3 is not provided.

Example.
In the embodiment, although not shown in the drawing, in the gap between the display region 100e and the display region 100f, a connection made of a laminate of the low-resistance metal film 150 and the cathode wiring 105, as shown in FIGS. A wiring 200 is formed.
A material having a surface resistance of about 0.1 ohm (Ω) / □ was used for the low resistance metal film 150. Specifically, the low-resistance metal film 150 is a stacked body in which a NiMo film having a thickness of 50 nm, an Al film having a thickness of 370 nm, a MoNb film having a thickness of 30 nm, and a NiMo film having a thickness of 50 nm are sequentially stacked. On the other hand, aluminum having a surface resistance of about 0.5 ohm (Ω) / □ was used for the cathode wiring 105.

The distance between the wiring centers of the connection wiring 200 is set to 0.35 mm which is the same as the distance between the wiring centers of the cathode wiring 105. The width of the low resistance metal film 150 is set to 0.33 mm which is the same as the width of the cathode wiring 105. The cathode wiring 105 constituting the connection wiring 200 is formed integrally with the cathode wiring 105 in each display region 100e, 100f, 100g.
Assuming that the organic EL display device configured as described above is operated by applying a drive voltage using, for example, a product name SSD1303 (withstand voltage 16 V) manufactured by Solomon, FIG. The virtual maximum resistance between both ends of the indicated length k = 76.8 mm wiring is 4200 ohms (Ω), and the assumed luminance (luminance at the center of the display region 100f) is 150 candela (cd) / m ² . .

Conventional example.
In the embodiment, the connection wiring 200 formed of the laminated body of the low-resistance metal film 150 and the cathode wiring 105 is used in the gap between the display area 100e and the display area 100f. In this case, the low resistance metal film 150 is not formed, and the cathode wiring 105 is simply provided in the gap between the display region 100e and the display region 100f. The cathode wiring 105 between the display areas 100e, 100f, and 100g is formed integrally with the cathode wiring 105 in the display areas 100e, 100f, and 100g. As in the example, aluminum having a surface resistance of about 0.5 ohm (Ω) / □ was used for the cathode wiring 105.

Assuming that the conventional example of the organic EL display device configured as described above is operated by applying a driving voltage using, for example, a product name SSD1303 (withstand voltage of 16 V) manufactured by Solomon, FIG. The virtual maximum resistance between both ends of the wiring having a length k = 76.8 mm indicated by is 7200 ohm (Ω), and the assumed luminance (luminance at the center of the display region 100f) is 90 candela (cd) / m ^2. It was.

Examples and conventional examples are summarized in Table 1.

As shown in Table 1, in the virtual maximum resistance, the example was 3000 Ω lower than the conventional example. In addition, in the assumed luminance, the example was 60 cd / m ² smaller than the conventional example.

  As described above, since the plurality of display areas 100e, 100f, and 100g are formed, it is necessary to add the connection wiring 200 that connects the plurality of display areas 100e, 100f, and 100g. Is made smaller than the surface resistance of the cathode wiring 105, an increase in the electrical resistance of the wiring can be suppressed, and the organic light emitting layer 107 can efficiently emit light with high luminance.

The above description is for explaining the embodiment of the present invention, and the present invention is not limited to the above embodiment. Moreover, those skilled in the art can easily change, add, and convert each element of the above embodiment within the scope of the present invention.
In the embodiment of the present invention, the passive organic EL display device has been described. However, the present invention can also be applied to an active organic EL display device.

In the above description of the embodiment, the dot matrix type organic EL display device is used as an example. However, the present invention is not limited to this, and the invention according to this embodiment can be applied to a segment type organic EL display device. .
Moreover, although the embodiment of the present invention has been described as an organic EL display device, the present invention can also be applied to an organic EL device manufactured for purposes other than display, such as an organic EL lighting device.

It is a figure which shows the structure of the organic electroluminescence display which concerns on Embodiment 1 of this invention, Comprising: It is a schematic diagram which shows the condition which observed the board | substrate from the side in which an electrode is formed. It is a figure which shows the structure of the organic electroluminescence display which concerns on Embodiment 1 of this invention, Comprising: It is sectional drawing in the XX cutting | disconnection line of FIG. It is a figure which shows the structure of the organic electroluminescence display which concerns on Embodiment 1 of this invention, Comprising: It is sectional drawing in the YY cut line of FIG. It is a figure which shows the structure of the organic electroluminescence display which concerns on Embodiment 2 of this invention, Comprising: It is a schematic diagram which shows the condition which observed the board | substrate from the side in which an electrode is formed. It is a figure which shows the structure of the organic electroluminescence display which concerns on Embodiment 1 of this invention, Comprising: It is sectional drawing in the ZZ cut line of FIG. It is a top view which shows the structure of the organic EL element substrate of the Example in Embodiment 1 of this invention, and a prior art example.

Explanation of symbols

1000, 1000a, 1000b Organic EL element substrate 100a, 100b, 100c, 100d Display area 100e, 100f, 100g Display area 101 Substrate 102 Anode wiring 103 Insulating film 103a Opening 105 Cathode wiring 105a Cathode auxiliary wiring 106 Cathode partition 107 Organic light emitting layer 108 Sealing substrate 109 Sealing material 110 Water trapping agent 150 Low resistance metal film 200, 200a Connection wiring

Claims (2)

An organic EL display device having a plurality of display areas separated from each other,
A substrate,
A first wiring formed on the substrate and disposed in the plurality of display areas;
A second wiring formed intersecting on the first wiring and disposed in the plurality of display areas;
An organic light emitting layer formed between the first and second wirings in the plurality of display regions;
A connection wiring that is formed between the plurality of display areas, and connects one of the first or second wirings in the plurality of display areas between the plurality of display areas;
2. The organic EL display device according to claim 1, wherein a surface resistance of the connection wiring is smaller than a surface resistance of the first or second wiring to be connected.   The connection wiring is a laminate of one of the first or second wiring to be connected and a metal film having a smaller surface resistance than that of the first or second wiring to be connected. 1. The organic EL display device according to 1.

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