KR20110046887A - Display device - Google Patents

Abstract

PURPOSE: A display device is provided to easily monitor a failure of an indentation of a conductive particle. CONSTITUTION: A display device comprises: a display panel for displaying an image through a substrate(120); a driving part for applying an image signal to the display panel; an ACF(Anisotropic Conductive Film)(140) for connecting the display panel and the driving part; a pad comprising an upper electrode and a lower electrode(144) which are connected with each other through a contact hole; and a dummy pad(114) on an insulating layer.

Description

Display device {DISPLAY DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly, to a display device for easily monitoring indentation defects of conductive particles.

Video display devices that realize various information as screens are the core technologies of the information and communication era, and are developing in a direction of thinner, lighter, portable and high performance. In recent years, with the development of the information society, various types of demands on display devices have increased, such as liquid crystal display (LCD), plasma display panel (PDP), electro luminescent display (ELD), field emission display (FED), and OLED ( Research on flat panel displays such as Organic Light Emitting Display is being actively conducted.

A liquid crystal display device displays an image by controlling a transmittance of light passing through a liquid crystal layer by disposing a common electrode on a front surface of a display panel where two substrates are bonded and rearranging liquid crystal molecules of the liquid crystal layer positioned between the two substrates. The organic light emitting diode display displays an image by adjusting an amount of current flowing through the organic light emitting diode positioned in the pixel electrode formed on the display panel.

Such a display apparatus generally includes a display panel including a display unit for displaying an image, a pad unit for supplying a signal of a driving unit to the display unit, and a driver unit for transmitting and controlling an input signal from the outside to the display panel. In order to supply a signal to the display panel, the electrode of the driving unit is a display panel according to a tape carrier package (TCP) mounting method, a chip on film (COF) mounting method, and a chip-on-glass (COG) mounting method. It is connected to the pad portion of.

In this case, the electrode of the driving unit is physically and electrically connected to the electrode of the pad unit using an anisotropic conductive film (ACF) including conductive particles for electrical connection and resin for physical connection. Monitoring of the energized state and working state of the electrode of a drive part and an electrode of a pad part is performed by using a separate measuring instrument or visually confirming the indentation degree of the electroconductive particle of ACF.

However, as the number of layers laminated between the conductive particles and the inner electrodes of the pad portion increases, the distance between the conductive particles and the inner electrodes of the pad portion increases, which makes it difficult to check the indentation degree of the conductive particles. In particular, it is difficult to confirm the energized state of the external electrode and the conductive particles by the opaque internal electrode.

Therefore, it is often the case that the heat and pressure in the ACF compression process is adjusted upward to easily observe the degree of indentation of the ACF conductive particles. However, the upwardly adjusted heat and pressure also affect the display panel, causing malfunction of the display device, thereby lowering the reliability of the display device.

The present invention has been made to solve the above problems, to provide a display device that is easy to monitor the indentation defect of the conductive particles.

A display device according to the present invention is defined as a display unit and a pad unit, and includes a display panel for realizing an image through a substrate, a driver for applying an image signal to the display panel, and an ACF connecting the display panel and the drive unit. Pads of the display panel may include pads including an upper electrode and a lower electrode connected through a contact hole with an insulating layer interposed therebetween, and a dummy pad spaced apart from the pad on the insulating layer. The driving part is provided with a dummy electrode facing the dummy pad.

The pad part is defined as a driving chip area and an FPC area, wherein the driving part includes a driving chip mounted on the substrate and an FPC attached to an edge of the display panel, and the driving chip is mounted on the driving chip area. The FPC is attached to the FPC region.

The lower electrode of the pad is electrically connected to the gate electrode of the display unit, the upper electrode of the pad is formed to be spaced apart from the source electrode and the data electrode of the display unit, and the dummy pad is a source electrode and the data of the display unit. It is formed spaced apart from the electrode.

At least one dummy pad is formed at one side, both sides, or the center of the pad.

The number of dummy pads and the number of dummy electrodes are the same.

The lower electrode of the pad is formed of the same material as the gate electrode formed on the display unit, the upper electrode of the pad is formed of the same material as the source and drain electrodes formed on the display unit, and the dummy pad is the display unit. It is formed of the same material as the source and drain electrodes formed on the, or spaced apart from the same material as the upper electrode of the pad.

An organic light emitting diode is formed on the display unit.

A bump pad electrically connected to the gate electrode of the display unit and a dummy pad for driving chip spaced apart from the bump pad may be formed in the driving chip area, and the bump pad may include a bump pad formed by extending the gate electrode. And an upper electrode of the bump pad electrically connected to the lower electrode of the bump pad with the insulating layer interposed therebetween, wherein the dummy pad for the driving chip is made of the same material as the source and drain electrodes. The pad is spaced apart from the pad and is formed on the insulating layer.

The dummy pad and the pad are formed in the FPC region.

The upper electrode of the bump pad is electrically connected to the bump electrode of the driving chip through the ACF, and the dummy pad for the driving chip is electrically connected to the bump dummy electrode of the driving chip through the ACF. The dummy pad is electrically connected to the lead electrode of the FPC through the ACF, and the dummy pad is electrically connected to the lead dummy electrode of the FPC through the ACF.

In the display device according to the present invention, since the lower electrode, which is an opaque metal material, is not formed under the driving chip dummy pad, the distance between the conductive particles of the ACF and the substrate becomes short, and the conduction state of the driving chip dummy pad and the ACF conductive particles is maintained. It is easy to monitor through the transparent insulating layers and the substrate.

In addition, since the display device according to the present invention easily monitors the indentation of the conductive particles of the ACF, heat and pressure need not be adjusted upward during the ACF compression process, so that the display device has less influence on the display panel, thereby improving reliability of the display device.

Hereinafter, a display device according to the present invention will be described in detail with reference to the accompanying drawings. 1A is a plan view of a display device according to the present invention, and FIG. 1B is a cross-sectional view taken along the line II ′ of the display device shown in FIG. 1A.

1A and 1B, a display device according to the present invention includes a display panel 110 for implementing an image, a driver 130 for applying an image signal to the display panel 110, a display panel 110, and a driver ( An anisotropic conductive film (ACF) 140 connecting the 130. The driver 130 includes a driving chip 134 and a flexible printing circuit board (FPC) 138.

The display panel 110 displays an image. The display panel 110 includes a display unit 116 including a plurality of sub-pixels formed on the substrate 120 and a pad unit for supplying an electrical signal to the display unit 116. It is defined as 118. The display panel 110 is formed by opposing the substrate 120 and the encapsulation substrate 101 to each other with a plurality of sub-pixels interposed therebetween.

The substrate 120 and the encapsulation substrate 101 are transparent insulating substrates made of glass, quartz, ceramic, or plastic. Instead of the encapsulation substrate 101, a protective film made of an insulating material may be used. Light emitted from the plurality of sub pixels is emitted to the outside through the encapsulation substrate 101. Thus, the user visually detects the image implemented through the encapsulation substrate 101.

One sub-pixel formed on the substrate 120 includes a plurality of signal lines, transistors, capacitors, and a plurality of insulating layers and devices. When the device is an organic light emitting device, the transistor includes a switching transistor and a driving transistor. The device according to the present invention is not limited to an organic light emitting device but may be applied to a liquid crystal display device or an electrophoretic device.

For example, if an organic light emitting element is applied, the switching transistor supplies a data signal from the data line in response to the scan signal of the gate line. The driving transistor controls the amount of current flowing through the organic light emitting element array in response to the data signal from the switching transistor. The capacitor serves to allow a constant current to flow through the driving transistor even when the switching transistor is turned off.

Referring to FIG. 2, the driving transistor includes a gate electrode 161 formed on the substrate 120, a gate insulating film 121 covering the gate electrode 161, and a gate insulating film 121 interposed therebetween. ) And an active layer 163 overlapping each other to form a channel, a source electrode 164 and a drain electrode 165 facing each other with the channel interposed therebetween, and a passivation layer 167 formed to expose the drain electrode 165. .

The organic light emitting diode OLED includes a first electrode 107 electrically connected to the drain electrode 165, a second electrode 103 serving as an opposite electrode, and a space between the first electrode 107 and the second electrode 103. And a bank insulating layer 108 that separates the formed organic light emitting layer 105 and the organic light emitting diode into sub pixel units.

The organic light emitting diode OLED further includes a spacer 109 for electrically connecting the driving transistor and the first electrode 107 and maintaining a constant gap between the substrate 120 and the encapsulation substrate 101 facing each other. It may include. The structure of the organic light emitting diode is not limited to the illustration of the figure may be a DOD type.

In the organic light emitting diode OLED, the axtone formed by combining holes and electrons injected from the first electrode 107 and the second electrode 103 by the driving current of the driving transistor falls to the ground state, and thus red, green, Emits blue or white light.

Referring to FIG. 3, the pad unit 118 of the display panel 110 is used to supply a power signal and a data signal to the display unit 116 and is defined as a driving chip region and an FPC region. However, the present invention is not limited thereto, and the driving chip region may be omitted. In the driving chip region, the driving chip is mounted on the substrate 120 in the form of a chip on glass (COG), and a bump pad 111 and a dummy pad 112 for the driving chip are formed for this purpose. In the FPC region, a film is attached to the edge of the substrate 120, and a pad 113 and a dummy pad 114 are formed therefor.

Referring to FIG. 4, the bump pad 111 and the dummy chip 112 for the driving chip are spaced apart from each other in one direction and formed on the driving chip area of the substrate 120. The bump pad 111 has the lower electrode 124 formed on the substrate 120, the gate insulating layer 121, and the insulating layer 122 interposed therebetween, and the lower electrode 124 through the contact hole. ) And an upper electrode 126 electrically connected thereto.

The lower electrode 124 of the bump pad 111 is formed at the same time as the gate electrode 161 in the display unit 116, and is formed on the same layer as the gate electrode 161. The lower electrode 124 of the bump pad 111 is formed by extending the gate electrode 161 in the display unit 116. The lower electrode 124 of the bump pad 111 is selected from an opaque metal material.

The upper electrode 126 of the bump pad 111 is formed at the same time as forming the source electrode and the drain electrode in the display unit 116, and may be formed on the same layer with the same material as the source and drain electrodes. The upper electrode 126 of the bump pad 111 is spaced apart from the source and drain electrodes in the display unit 116.

The upper electrode 126 of the bump pad 111 is electrically connected to the bump electrode 131 of the driving chip 134 through the conductive particles 142 of the ACF 140. Therefore, the lower electrode 124 of the bump pad 111 is electrically connected to the bump electrode 131 of the driving chip 134. The upper electrode 126 of the bump pad 111 is selected from an opaque metal material.

The driving pad dummy pad 112 is formed on the substrate 120 with the gate insulating layer 121 and the insulating layer 122 interposed therebetween. The dummy pad 112 for the driving chip is formed at the same time when the source electrode and the drain electrode are formed in the display unit 116, and may be formed on the same layer with the same material as the source and drain electrodes.

 The driving chip dummy pad 112 is formed of the same material as the upper electrode 126 of the bump pad 111 and is spaced apart from the upper electrode 126 of the bump pad 111 on the same layer. The dummy pad 112 for the driving chip is electrically connected to the bump dummy electrode 132 of the driving chip 134 and the conductive particles 142 of the ACF 140.

The driving pad dummy pad 112 is selected from an opaque metal material and is spaced apart from the source and drain electrodes in the display unit 116. The driving chip dummy pad 112 may be spaced apart from one side, both edges, or the center of the bump pad 111.

Unlike the bump pad 111, the lower electrode is not formed under the driving chip dummy pad 112, so that the distance between the conductive particles of the ACF 140 and the substrate 120 is closer to the conductive particles through the substrate 120. It is easy to check the degree of indentation.

In particular, since the lower electrode, which is an opaque metal material, is not formed, it is easy to monitor the conduction state of the driving pad dummy pad 112 and the conductive particles of the ACF 140 through the transparent insulating layers and the substrate 120. Therefore, as the degree of indentation of the ACF 140 conductive particles is easily observed, there is no need to adjust heat and pressure upward during the ACF 140 pressing process, thereby reducing the influence on the display panel 110, thereby improving reliability of the display device. .

The insulating layer 122 may be formed of the same material as the interlayer insulating layer or the protective layer 167 in the display unit 116.

Referring to FIG. 5, a plurality of pads 113 and dummy pads 114 are spaced apart from each other in one direction and are formed on the FPC region of the substrate 120. The pad 113 may include the lower electrode 144 formed on the substrate 120, the gate insulating layer 121, and the insulating layer 122 therebetween, and the lower electrode 144 through the contact hole. An upper electrode 146 electrically connected thereto.

The lower electrode 144 of the pad 113 is simultaneously formed when the gate electrode 161 in the display unit 116 is formed, and is formed on the same layer as the gate electrode 161. The lower electrode 144 of the pad 113 is formed by extending the lower electrode 124 of the bump pad 112 formed by extending the gate electrode 161 in the display unit 116. The lower electrode 144 of the pad 113 is selected from an opaque metal material.

The upper electrode 146 of the pad 113 is formed at the same time as forming the source electrode and the drain electrode in the display unit 116, and may be formed on the same layer of the same material as the source and drain electrodes. The upper electrode 146 of the pad 113 is formed to be spaced apart from the upper electrode 126 of the bump pad 111 and the dummy pad 112 for the driving chip.

The upper electrode 146 of the pad 113 is electrically connected to the lead electrode 135 of the FPC 138 through the conductive particles 142 of the ACF 140. Accordingly, the lower electrode 144 of the pad 113 is electrically connected to the lead electrode 135 of the FPC 138. The upper electrode 146 of the pad 113 is selected from an opaque metal material.

The dummy pad 114 of the FPC region is formed on the substrate 120 with the gate insulating layer 121 and the insulating layer 122 interposed therebetween. The dummy pad 114 is formed at the same time as forming the source electrode and the drain electrode in the display unit 116, and may be formed on the same layer with the same material as the source and drain electrodes.

The dummy pad 114 is selected from an opaque metal material and is spaced apart from each other on the same layer by the same material as the source and drain electrodes of the display unit 116, the dummy pad 112 for the driving chip, and the upper electrode 126 of the pad 113. Is formed. The dummy pad 114 is electrically connected to the lead electrode 135 of the FPC 138 and the conductive particles 142 of the ACF 140.

The dummy pad 114 may be formed to be spaced apart from the pad 113 at one side, both edges, or the center of the pad 113. One or more dummy pads 114 are formed on the display panel 110. Unlike the pad 113, a lower electrode is not formed below the dummy pad 114, so that the distance between the conductive particles of the ACF 140 and the substrate 120 is closer to the indentation level of the conductive particles through the substrate 120. It is easy to check.

In particular, since the lower electrode, which is an opaque metal material, is not formed, it is easy to monitor the conduction state of the conductive particles of the dummy pad 114 and the ACF 140 through the substrate 120 and the transparent insulating layers. Therefore, as the degree of indentation of the ACF 140 conductive particles is easily observed, there is no need to adjust heat and pressure upward during the ACF 140 pressing process, thereby reducing the influence on the display panel 110, thereby improving reliability of the display device. .

The driver 130 is electrically connected to a plurality of pads formed in the pad unit 118 of the display panel 110 to supply driving signals and power signals to the plurality of sub-pixels in the display unit 116. To this end, the driving unit 130 includes a driving chip 134 and an FPC 138, and is electrically connected to the pad unit 118 of the display panel 110 through the ACF 140. The driver 130 may further include a printed circuit board (PCB) on which components generating various control signals and data signals are mounted.

The driving chip 134 includes a bump electrode 131 facing the upper electrode 126 of the bump pad 111 and a bump dummy electrode 132 facing the dummy pad 112 for the driving chip. The FPC 138 includes a lead electrode 135 opposing the upper electrode 146 of the pad 113 and a lead dummy electrode 136 opposing the dummy pad 114. That is, the number of bump dummy electrodes 132 is the same as the number of dummy pads 112 for driving chips, and the number of lead dummy electrodes 136 is the same as the number of dummy pads 112.

The ACF 140 is an electrically conductive film for electrically connecting the driver 130 and the display panel 110. The ACF 140 includes a plurality of conductive particles 142 and a resin 144 surrounding the conductive particles 142 to electrically connect the electrodes and the pads through the conductive particles 142.

As a result, driving signals such as a power signal, a scan signal, and an image signal are supplied to the pad 1114 of the display panel 110 through the FPC 138 and the ACF 140, and the pad 114 is provided with the driving chip 134 and A driving signal is applied to the plurality of sub-pixels of the display unit of the display panel 110 through the ACF 140 to implement an image through the display panel 110.

The driving chip refers to either a gate driving semiconductor chip package or a data driving semiconductor chip package. In addition, although the present invention has been described with reference to the organic light emitting diode as an example, the present invention is not limited to the display device including the organic light emitting diode.

The bump pad, the dummy chip for the driving chip, the number of pads, the dummy pads, and the arrangement order are not limited to those illustrated in the drawings. The number of driving chips can be variously changed according to the resolution.

 It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be clear to those who have knowledge of.

1A is a plan view of a display device according to the present invention.

FIG. 1B is a cross-sectional view taken along the line II ′ of the display device illustrated in FIG. 1A.

2 is a cross-sectional view illustrating an element structure formed in a display unit of a display panel of a display device according to the present invention.

3 is a plan view illustrating a pad part of a display panel of the display device according to the present invention.

FIG. 4 is a view in which the driving chip is mounted on a sectional view taken along the line II-II 'of FIG. 3.

FIG. 5 is a diagram in which the FPC is attached to a cross-sectional view of the pad part shown in FIG. 3 taken along line III-III '.

<< Explanation of symbols for main part of drawing >>

111: bump pad 112: dummy pad for the driving chip

113: pad 114: dummy pad

116: display portion 118: pad portion

131: bump electrode 132: bump dummy electrode

134: driving chip 135: lead electrode

136: lead dummy electrode 138: FPC

140: ACF

Claims (10)

A display panel defined by a display unit and a pad unit, and configured to implement an image through a substrate; A driver which applies an image signal to the display panel; And An ACF connecting the display panel and the driving unit; Pads of the display panel may include pads including an upper electrode and a lower electrode connected through a contact hole with an insulating layer interposed therebetween, and a dummy pad spaced apart from the pad on the insulating layer. And a dummy electrode facing the dummy pad is formed in the driving part. The method of claim 1, wherein the pad portion is defined as a driving chip region and an FPC region, The driving unit is a driving chip mounted on the substrate, An FPC attached to an edge of the display panel, The driving chip is mounted in the driving chip region, And the FPC is attached to the FPC region. The display device of claim 1, wherein the lower electrode of the pad is electrically connected to a gate electrode of the display unit, and the upper electrode of the pad is formed to be spaced apart from a source electrode and a data electrode of the display unit. And the dummy pad is spaced apart from the source electrode and the data electrode of the display unit. The display device of claim 1, wherein at least one dummy pad is formed on one side, both sides, or the center of the pad. The display device of claim 1, wherein the number of the dummy pads and the number of the dummy electrodes are the same. The display device of claim 1, wherein the lower electrode of the pad is formed of the same material as the gate electrode formed on the display unit, and the upper electrode of the pad is formed of the same material as the source and drain electrodes formed on the display unit. And the dummy pad is formed of the same material as the source and drain electrodes formed on the display unit, or is spaced apart from the same material as the upper electrode of the pad. The display device of claim 1, wherein an organic light emitting element is formed in the display unit.  The method of claim 2, wherein the driving chip region is formed with a bump pad electrically connected to the gate electrode of the display unit and a dummy pad for the driving chip spaced apart from the bump pad, The bump pad includes a lower electrode of the bump pad in which the gate electrode extends, and an upper electrode of the bump pad electrically connected to the lower electrode of the bump pad with the insulating layer therebetween. and, And the dummy pad for the driving chip is formed on the insulating layer to be spaced apart from the bump pad with the same material as the source and drain electrodes. The display device of claim 2, wherein the dummy pad and the pad are formed in the FPC region. The method of claim 8, wherein the upper electrode of the bump pad is electrically connected to the bump electrode of the driving chip through the ACF, The dummy pad for the driving chip is electrically connected to the bump dummy electrode of the driving chip through the ACF. The pad is electrically connected to the lead electrode of the FPC through the ACF, And the dummy pad is electrically connected to the lead dummy electrode of the FPC through the ACF.

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