KR20080014426A - Organic electro-luminescence display - Google Patents

Abstract

An organic electro-luminescence display device is provided to increase the number of contact-hole of a common voltage and a driving voltage on a pad unit by forming the contact-holes of the common voltage pad unit and the driving voltage pad unit closely which are formed on the display panel. An organic electro-luminescence display device comprises a light emitting unit(50), and a pad unit. The light emitting unit displays an image using an organic light emitting cell having an organic layer formed between a cathode electrode and an anode electrode. The pad unit provides a driving signal to at least one of the cathode electrode and the anode electrode. The pad unit has a first conductive layer(96), a second conductive layer(98), and insulation layer. The first conductive layer is formed on a substrate. The second conductive layer is connected to the first conductive layer. The insulation layer has a plurality of contact holes which are formed between the first conductive layer and the second conductive layer. The insulation layer is formed as at least one layer of a multi-step structure.

Description

Organic electroluminescent display device {ORGANIC ELECTRO-LUMINESCENCE DISPLAY}

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

2 is a plan view illustrating a contact hole of a common voltage pad unit according to the present invention.

3 is a cross-sectional view illustrating a contact hole of a common voltage pad unit according to the present invention.

<Brief description of symbols for the main parts of the drawings>

20: data pad portion 30: data pad portion

40: driving voltage pad part 50: light emitting part

60: common voltage pad portion 70: substrate

80 supply line 82 common voltage line

91: contact hole 92: the first contact hole

93: first insulating portion 94: second contact hole

95: second insulating portion 96: first conductive layer

97: insulating film 98: second conductive layer

The present invention relates to an organic light emitting display device, and more particularly, to an organic light emitting display device capable of reducing the outermost size of a display panel.

In general, an organic light emitting display device is a display device that emits light when a driving current is applied to a fluorescent organic compound. The organic light emitting display device displays an image by driving N * M organic light emitting cells. In this case, the organic light emitting cell includes an anode electrode, a cathode electrode facing the anode electrode, and an organic light emitting layer formed between the anode electrode and the cathode electrode.

The driving voltage VDD is supplied to the anode electrode and the common voltage VCOM is supplied to the cathode electrode to emit light of the organic light emitting cell. The driving voltage pad portion for supplying the driving voltage to the anode electrode and the common voltage pad portion for supplying the common voltage to the cathode electrode are positioned on the outer portion of the substrate. There is a problem that the outer portion of the substrate becomes larger by the area occupied by the driving voltage pad portion and the common voltage pad portion on the substrate. In particular, as the size of the substrate increases, the driving voltage and the common voltage pad portion also increase the driving voltage and the common voltage level. Therefore, the driving voltage pad portion and the common voltage pad portion have a problem in that the area occupied by the substrate is also increased in order to facilitate voltage supply.

Accordingly, an aspect of the present invention is to provide an organic light emitting display device capable of reducing the outermost size of a display panel.

In order to achieve the above technical problem, the organic light emitting display device according to the present invention includes a light emitting unit for displaying an image using an organic light emitting cell comprising an organic layer formed between the cathode electrode and the anode electrode; A pad portion supplying a driving signal to at least one of the cathode electrode and the anode electrode, the pad portion comprising: a first conductive layer formed on a substrate; A second conductive layer connected to the first conductive layer; And at least one insulating layer having a plurality of contact holes formed between the first and second conductive layers adjacent to each other and having a multi-stage structure.

The at least one insulating layer may be formed on the first conductive layer in a multi-stage structure in which the width thereof becomes narrower as it moves away from the first conductive layer.

In addition, the contact hole may include a first contact hole penetrating the insulating layer of the at least one layer with a first width to expose the first conductive layer; And a second contact hole vertically connected to the first contact hole and penetrating the at least one insulating layer to a second width wider than the first width.

Here, the distance between the first contact hole and the first contact hole is characterized in that 0.3 ~ 0.5mm.

The pad part may be a common voltage pad part supplying a common voltage to the cathode electrode.

Other technical problems and advantages of the present invention in addition to the above technical problem will be apparent from the description of the preferred embodiment of the present invention with reference to the accompanying drawings.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to FIGS. 1 to 3.

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

The organic light emitting display shown in FIG. 1 includes a light emitting unit 50 for displaying an image, a data pad unit 20 for supplying a data signal to a data line DL of the light emitting unit 50, and a gate signal. A gate pad unit 30 which is generated and supplied to the gate line GL of the light emitting unit 50, a common voltage pad unit 60 which supplies a common voltage VCOM to the light emitting unit 50, and a driving voltage ( A driving voltage pad part 40 for supplying VDD to the light emitting part 50.

The light emitting unit 50 is positioned on the substrate 70 together with the driving voltage pad unit 40 and the common voltage pad unit 60 and protected by an encap bonded to the substrate 70. The light emitting unit 50 includes a plurality of subpixels, and each subpixel includes a cell driver connected to a gate line GL, a data line DL, and a power supply line.

The cell driver is connected between the switch thin film transistor T1 connected to the gate line GL and the data line DL, a power supply line supplying the switch thin film transistor T1 and the driving voltage VDD, and an anode of the OEL cell. The driving thin film transistor T2 and the storage capacitor Cst connected between the power supply line and the drain electrode of the switch thin film transistor T1.

The gate electrode of the switch thin film transistor T1 is connected to the gate line GL, the source electrode is connected to the data line DL, and the drain electrode is connected to the gate electrode and the storage capacitor Cst of the driving thin film transistor T2. do. The source electrode of the driving thin film transistor T2 is connected to the power supply line and the drain electrode is connected to the pixel electrode serving as the anode of the OEL cell. The storage capacitor Cst is connected between the power supply line and the gate electrode of the driving thin film transistor T2.

The switch thin film transistor T1 is turned on when a scan pulse is supplied to the gate line GL, and supplies the data signal supplied to the data line DL to the gate electrode of the storage capacitor Cst and the driving thin film transistor T2. do. The driving thin film transistor T2 controls the amount of light emitted from the OEL cell by controlling the current I supplied from the power line to the OEL cell in response to the data signal supplied to the gate electrode. In addition, even when the switch thin film transistor T1 is turned off, the driving thin film transistor T2 is supplied with a constant current I until the data signal of the next frame is supplied by the voltage charged in the storage capacitor Cst. Keep the cell luminescent.

The OEL cell includes an anode electrode supplied with the driving voltage Vdd from the power line through the driving thin film transistor T2, a cathode electrode supplied with the common voltage Vcom, and a light emitting layer formed between the anode electrode and the cathode electrode. It consists of an organic layer. The organic layer is composed of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer laminated from a pixel electrode. The light emitting layer included in the organic layer emits light according to the amount of current supplied to the anode electrode and emits light toward the substrate or the encap via the anode electrode or the cathode electrode.

The data pad unit 20 supplies a data signal generated by the data driver integrated circuit to the data line DL positioned in the light emitting unit. To this end, the data pad unit 20 is connected to the tape carrier package in which the data driving integrated circuit is mounted and to the data line DL. The data pad part 20 is formed on the upper side of the substrate 70. On the other hand, the data driving integrated circuit may be directly mounted on the substrate 70 or formed of a plurality of transistors having the same structure as the driving thin film transistor T2 on the substrate 70.

The gate pad part 30 supplies a gate signal generated by the gate driving integrated circuit to the gate line GL positioned in the light emitting part. For this purpose, the gate pad part 30 is connected to the tape carrier package on which the gate driving integrated circuit is mounted and to the gate line GL. The gate pad part 30 is formed on the left side of the substrate 70. Meanwhile, the gate driving integrated circuit is directly mounted on the substrate 70 or formed of a plurality of transistors having the same structure as the driving thin film transistor T2 on the substrate 70.

The driving voltage pad part 40 is formed between the light emitting part 50 and the data pad part 20. The driving voltage pad part 40 is supplied with a driving voltage Vdd generated by a power supply unit mounted on a separate printed circuit board, and a power line PL having the driving voltage Vdd in the light emitting unit 50. Supplies). Meanwhile, the contact hole 91 included in the driving voltage pad part 40 has the same structure as the contact hole 91 of the common voltage pad part 60.

The common voltage pad part 60 is formed between the light emitting part 50 and the gate pad part 30. The common voltage pad part 60 supplies the common voltage Vcom to the cathode of the light emitting cell positioned in the light emitting part 50. To this end, the common voltage pad unit 60 may include at least one first conductive layer 96 formed on the substrate 70 and at least one first conductive layer 96 as illustrated in FIGS. 2 and 3. The insulating film 97 of the layer, the contact hole 91 formed to penetrate the insulating film 97 to expose the first conductive layer 96, and the first conductive layer 96 connected through the contact hole 91. A second conductive layer 98 is included.

The first conductive layer 96 is supplied with the common voltage Vcom generated by the power supply unit mounted on a separate printed circuit board through the supply line 80.

At least one insulating layer 97 is formed to have a plurality of contact holes 91 between the first conductive layer 96 and the second conductive layer 97. That is, at least one insulating layer 97 is formed on the first conductive layer 96 and is formed between the contact holes 91. Accordingly, the at least one insulating layer 91 has a first insulating portion 93 having a first width W1 on the first conductive layer 96 and a first width on the first insulating portion 93. The second insulating portion 95 having a second width W2 narrower than the width W1 is included. The first and second insulating parts 93 and 95 may be integrally formed with one insulating film 97 or may be formed with different insulating films 97. On the other hand, the at least one insulating film 97 has a multi-stage structure that becomes narrower as it moves away from the first conductive layer 96. The first and second insulating portions 93 and 95 are formed on the first conductive layer 96. It has been described taking the form of a two-stage structure by way of example, but can also be formed of a structure of two or more stages. Here, the width of the second insulating portion 95 is 0.3 to 0.5 mm, preferably 0.4 mm.

The contact hole 91 includes first and second contact holes 92 and 94 formed to penetrate at least one insulating layer 97 at different widths. The first contact holes 92 and 94 are formed to penetrate at least one layer of the insulating layer 91 at a first width W1, and the second contact hole 94 is a second width wider than the first width W1. It is formed to pass through the insulating film 97 of at least one layer (W2) and is connected to the first contact hole 92. As described above, the number of the contact holes 91 according to the present invention having the first and second contact holes 92 and 94 is increased by about 70 to 80% or more compared with the conventional contact holes.

The second conductive layer 98 is connected to the first conductive layer 96 through the contact hole 91 and to the common voltage line 82. Accordingly, the second conductive layer 98 has a common voltage Vcom connected to the cathode electrode positioned in the light emitting unit 50 with the common voltage Vcom from the supply line 80 connected to the first conductive layer 96. 82). Here, the second conductive layer 98 is formed not only on the upper surface of the first conductive layer 96 exposed through the contact hole 91 but also on the side surfaces and the upper surfaces of the insulating film 97 formed in a multi-stage structure. . In this case, the second conductive layer 98 has a relatively large area occupied by the common voltage pad unit 60 as compared with the second conductive layer 98 of the conventional common voltage pad unit 60. Accordingly, the common voltage pad unit 60 according to the present invention can smoothly supply the common voltage Vcom as compared to the conventional common voltage pad unit 60.

On the other hand, when the second conductive layer 98 is formed to have the same area as the related art, the common voltage pad part 60 is used in the display device when the contact hole is increased by reducing the width of the adjacent insulating layer or when the number of contact holes that are used are used. It can reduce the area occupied by). The common voltage pad part 60 according to the present invention is reduced in width by about 40 to 50% or more compared with the conventional common voltage pad part. Accordingly, the size of the organic light emitting display device may be reduced by the area where the common voltage pad unit 60 is reduced.

As described above, in the organic light emitting display device according to the present invention, contact holes formed in the common voltage pad portion and the driving voltage pad portion formed on the display panel are closely formed.

Accordingly, the size of the pad portion of the common voltage and the driving voltage is reduced, so that the outermost size of the display panel may be reduced, or the number of contact holes of the common voltage and the driving voltage may be increased to the size of the pad portion that is used previously.

In addition, since the size of the display panel is reduced, an increase in power consumption can be prevented.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the technical spirit of the present invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the description of the specification but should be defined by the claims.

Claims (5)

A light emitting unit displaying an image using an organic light emitting cell including an organic layer formed between the cathode and the anode; A pad unit supplying a driving signal to at least one of the cathode electrode and the anode electrode, The pad part A first conductive layer formed on the substrate; A second conductive layer connected to the first conductive layer; And at least one insulating layer having a plurality of contact holes formed adjacent to each other between the first and second conductive layers and having a multi-stage structure. The method of claim 1, The at least one insulating film layer The organic light emitting display device of claim 1, wherein the organic light emitting display device is formed on the first conductive layer in a multi-stage structure in which the width becomes narrower as the distance from the first conductive layer increases. The method of claim 1, The contact hole is A first contact hole penetrating the at least one insulating layer with a first width to expose the first conductive layer; And a second contact hole vertically connected to the first contact hole and penetrating the insulating layer of the at least one layer to a second width wider than a first width. The method of claim 3, wherein And an interval between the first contact hole and the first contact hole is 0.3 to 0.5 mm. The method of claim 1, And the pad part is a common voltage pad part supplying a common voltage to the cathode electrode.

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