KR20110034789A - Organic light emitting display device and manufacturing method of the same - Google Patents

Abstract

PURPOSE: An organic light emitting display device and a manufacturing method thereof are provided to minimize adhesion difference with an ACF(Anisotropic Conductive Film) by forming an COF(Chip On Film) film and an FPC film with the same materials. CONSTITUTION: A display panel comprised of a display unit which implements images and a pad unit which applies a driving signal to the display unit is prepared(S2). An ACF is formed on one side of the pad unit. The COF film and the FPC film are simultaneously aligned on the pad unit of the display panel(S4). The COF film and the FPC film are bonded with the pad unit by pressurizing the COF film and the FPC film(S6). The display panel is finally inspected(S8).

Description

Organic light emitting display and manufacturing method thereof {ORGANIC LIGHT EMITTING DISPLAY DEVICE AND MANUFACTURING METHOD OF THE SAME}

The present invention relates to an organic light emitting display device and a method of manufacturing the same, and more particularly, to an organic light emitting display device and a method of manufacturing the same that can improve reliability by preventing alignment defects and conductive ball indentation defects.

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.

Among them, an organic light emitting display (OLED), which displays an image by controlling the amount of light emitted from the organic light emitting layer, has been spotlighted as a flat panel display that can reduce weight and volume, which is a disadvantage of a cathode ray tube (CRT). An organic light emitting display device is a self-luminous device using a thin light emitting layer between electrodes, and has an advantage of thinning like a paper.

Such an organic light emitting display device includes a flat panel display panel that implements an image and a driving unit that supplies image data to the flat panel display panel. In order to input image data to the flat panel display panel, the driving unit displays the flat panel display according to a TCP (Tape Carrier Package) mounting method, a Chip on Film (COF) mounting method, and a Chip-On-Glass (COG) mounting method. Can be connected with the panel.

The COG mounting method does not need to form TCP separately, thereby reducing the manufacturing cost, but has the disadvantage of increasing the size of the glass substrate required for manufacturing the display device. TCP is a method of mounting a driving chip on a film including an insulating film and a metal thin film, and a circuit pattern connected to the driving chip is formed on the metal thin film. Chip-On-Film has the advantage of being able to bend more than 90 degrees using a material that is more flexible than TCP.

In the module process of the organic light emitting display device, the driving unit is electrically connected to the flat panel display panel by using an anisotropic conductive film (ACF) containing conductive balls therein by using a TCP mounting method and a COF mounting method. At this time, since the driving unit by the COF mounting method is electrically connected first and then the driving unit by the TCP mounting method is electrically connected, the process is complicated, yields are lowered, and alignment defects of the circuit lines are generated.

In addition, the film used in the TCP mounting method and the COF mounting method is different from each other, the pressure difference caused by the step difference during the pressurization using the ACF caused a bad indentation of the conductive ball to reduce the reliability of the organic light emitting display device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide an organic light emitting display device and a method of manufacturing the same, which can improve reliability by preventing alignment defects and conductive ball indentation defects.

According to an aspect of the present invention, there is provided a method of manufacturing an organic light emitting display device, the method comprising: preparing a display panel including an organic light emitting diode module configured to display an image and a pad unit applying a driving signal to the display unit; Forming an ACF, aligning the film for the COF and the film for the FPC at the same time to the pad portion of the display panel, and performing a pressing process on the film for the COF and the film for the FPC. Bonding an FPC film to the pad portion through the ACF.

The film for COF and the film for FPC are formed to the same thickness.

The film for COF and the film for FPC are formed of the same material.

The pressing step is performed by pressing the film for COF and the film for FPC at the same pressure.

Alternatively, the pressing step includes pressing the COF film and the FPC film at a first pressure, and pressing the COF film or the FPC film with a thin thickness at a second pressure.

Alternatively, the pressing step includes pressing the COF film and the FPC film at a first pressure, and pressing the FPC film at a second pressure.

A power signal is applied through the film for COF, and a scan signal and a data signal are applied through the film for FPC.

An organic light emitting display device according to the present invention includes a display panel consisting of an organic light emitting diode module for displaying an image and a pad portion for applying a driving signal to the display portion, a COF film and an FPC attached to one side of the pad portion. ACF containing the conductive film for electrically connecting the film for CO and the said film for COF, and the said film for FPC to the said display panel.

The organic light emitting display device and the method of manufacturing the same according to the present invention can simplify the process by simultaneously performing the attaching process of the film for COF and the film for FPC, it is possible to improve the yield by preventing alignment failure.

In addition, the present invention can form a film for COF and a film for FPC by the same material can minimize the difference in adhesion with the ACF.

In addition, the present invention can improve the reliability of the organic light emitting display device by preventing the indentation defect with the conductive ball of the ACF due to the height difference by the same thickness of the film for COF and the film for FPC.

Hereinafter, an organic light emitting display device and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings.

1A and 1B, an organic light emitting display device according to an exemplary embodiment of the present invention includes a display panel 110 that implements an image by using an organic light emitting diode module and a driver 190 that applies an image signal to the display panel 110. And a conductive film 150 connecting the display panel 110 and the driver 190.

The display panel 110 displays an image, and is defined as a display unit in which a plurality of pixels are formed and a pad unit supplying electrical signals to the display unit, and an encapsulation substrate bonded to the device substrate 120 and the device substrate 120. 140). A polarizer (not shown) may be attached to the front surface of the display panel 120 to improve viewing angle characteristics of the image.

The device substrate 120 is a transparent insulating substrate made of glass, quartz, ceramic or plastic. The encapsulation substrate 140 protects the cell driver array 132 and the organic light emitting diode array 134 formed on the display unit of the device substrate 120 from external impact and prevents impurities from penetrating. The cell driver array 132 ) And the organic light emitting diode array 134 therebetween are attached to the device substrate 120. In this case, the encapsulation substrate 140 may be formed of the same material or a metal material as the device substrate 120, but is not limited thereto.

The cell driver array 132 includes a plurality of sub pixel drivers, and one sub pixel driver includes a plurality of signal lines, a transistor, a capacitor, and a plurality of insulating layers, and the transistor includes a switch transistor and a driving transistor. do.

The switching transistor supplies a data signal from the data line in response to the scan signal of the gate line, and 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.

The organic light emitting element array 134 is divided into a plurality of sub-pixels, and emits red, green, and blue light in accordance with the flow of current to display predetermined image information. The organic light emitting diode array 134 includes a first electrode connected to the driving transistor, a second electrode serving as an opposing electrode, and an organic light emitting layer disposed between and emitting light.

The first electrode is used as the anode electrode and the second electrode is used as the cathode electrode. The organic light emitting layer is a layer in which light is emitted while the axtone formed by combining holes and electrons injected from the first electrode and the second electrode falls to the ground state, and emits red, green, and blue light in sub-pixel units.

A driving unit 190 for supplying driving signals and power signals to a plurality of pixels included in the display unit is attached to the pad unit formed at one side of the long side of the display panel 110. The driving unit 190 includes a film 160 for a chip on film (COF), a film 170 for a flexible printed circuit (FPC), and a printed circuit board (PCB), and an anisotropic conductive film (ACF) 150. ) Is electrically connected to the pad portion of the display panel 110 through.

The film 160 for COF is used to apply a power signal to the display panel 110 and includes an insulating base film, a signal line (not shown) of a metal thin film formed on the base film, and a driving chip 164. The film 160 for COF is attached to the ACF 150 through the COF solder resistor 162 on both edges of the pad portion of the display panel 110.

The FPC film 170 is for applying scan signals and image data to the display panel 110. The FPC film 170 protects an insulating flexible film, circuit patterns (not shown) and circuit patterns printed on the upper and lower portions of the flexible film. Protective film. The FPC film 170 is attached to the ACF 150 through the FPC solder resistor 172 between the COF film 160 in the pad portion of the display panel 110. However, the present invention is not limited thereto, and the FPC film 170 may include a driving chip necessary to transmit a driving signal.

At this time, the film for COF 160 and the film for FPC 170 is made of the same material to make the adhesion of the ACF 150 the same. In addition, the same thickness of the COF film 160 and the FPC film 170 to prevent the pressure difference due to the step height of the film when attached to the ACF 150, the indentation defect of the conductive ball of the ACF 150 To prevent. As a result, the reliability and yield of the organic light emitting display device according to the present invention are improved.

The ACF 150 is used to electrically connect the driving unit 190 and the display panel 110, and is an adhesive conductive film. The ACF 150 electrically connects the COF film 160 and the FPC film 170 on which the driving chip 164 is mounted, including the conductive balls, to the pad portion of the display panel 110.

As a result, driving signals such as a power signal, a scan signal, and an image signal from a printed circuit board (not shown) may be applied to the pad of the display panel 110 through the COF film 160, the FPC film 170, and the ACF 150. The pad unit applies a driving signal to the cell driver array of the display unit of the display panel 110, and the cell driver array drives the organic light emitting diode to implement an image through the display panel 110.

Hereinafter, a method of manufacturing an organic light emitting display device according to the present invention will be described.

Referring to FIG. 2, after the display panel is prepared (step S2), one side of the film for COF and the film for FPC are simultaneously attached to one side of the exposed display panel (step S4). Subsequently, the other side of the film for COF and the film for FPC is attached to the printed circuit board (PCB) (step S6), and then an organic light emitting display device is manufactured by performing final inspection (step S8) of the display panel. Looking at this in detail.

Referring to FIG. 3A, a display panel 110 defined by a display unit D in which a plurality of pixels are formed and a pad unit P for supplying an electrical signal to the display unit D is prepared. The display panel 110 displays an image and includes an element substrate 120 and an encapsulation substrate 140 bonded to the element substrate 120. A polarizer (not shown) may be attached to the front surface of the display panel 120 to improve the viewing angle characteristic of the image.

The device substrate 120 is a transparent insulating substrate made of glass, quartz, ceramic or plastic. The encapsulation substrate 140 protects the cell driver array 132 and the organic light emitting diode array 134 formed on the display unit D of the device substrate 120 from external impact and prevents impurities from penetrating the cell driver. The array is attached to the device substrate 120 with the array (not shown) and the organic light emitting device array (not shown) therebetween. In this case, the encapsulation substrate 140 may be formed of the same material or a metal material as the device substrate 120, but is not limited thereto.

The cell driver array (not shown) includes a plurality of sub pixel drivers, and one sub pixel driver includes a plurality of signal lines, a transistor, a capacitor, and a plurality of insulating layers, and the transistor includes a switch transistor and a driving transistor. Include.

The switching transistor supplies a data signal from the data line in response to the scan signal of the gate line, and 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.

The organic light emitting diode array (not shown) is divided into a plurality of sub-pixels and emits red, green, and blue light according to the flow of current to display predetermined image information. A second electrode which is an electrode and an organic light emitting layer disposed between and emitting light.

The first electrode is used as the anode electrode and the second electrode is used as the cathode electrode. The organic light emitting layer is a layer in which light is emitted while the axtone formed by combining holes and electrons injected from the first electrode and the second electrode falls to the ground state, and emits red, green, and blue light in sub-pixel units.

Referring to FIG. 3B, an ACF 150 is formed on one side of the pad portion P of the display panel 110. The ACF 150 is for electrically connecting the driving unit (not shown) and the display panel 110 and is an adhesive conductive film. The ACF 150 includes an adhesive and a conductive ball to allow the driving unit to be electrically connected to the display panel 110.

Referring to FIG. 3C, the COF film 160 and the FPC film 170 are simultaneously aligned in line on the ACF 150 formed on the pad portion P of the display panel 110, and then pressurized to press the ACF 150. ) And bond together. As a result, the conductive balls included in the ACF 150 are pressed so that the signal line of the COF film 160 and the circuit pattern of the FPC film 170 and the display panel 110 are simultaneously energized.

As described above, the present invention can simplify the process by simultaneously attaching the film 160 for COF and the film 170 for FPC to the display panel 110, thereby improving yield. In addition, alignment defects between the lead wires (not shown) formed on the pad part of the display panel 110, the signal line of the COF film 160, and the circuit pattern of the FPC film 170 may be minimized.

The attachment portion A of the COF film 160 and the FPC film 170 will be described in detail with reference to FIGS. 3D and 3E. Referring to FIG. 3D, even if the thickness of the COF film 160 and the FPC film 170 are equalized and pressurized to the same pressure, the conductive ball of the ACF 150 may be formed due to a step height. To prevent indentation defects).

In order to make the thickness of the film 160 for COF and the film 170 for FPC the same, it can achieve by making the thickness of the signal line or circuit pattern of the metal thin film formed in a thinner film thick. In addition, the COF film 160 and the FPC film 170 may be formed to have the same thickness with the same material, and when the COF film 160 and the FPC film 170 are made of the same material, the ACF 150 may be formed. ), The difference in adhesion with) is minimized, so it is more firmly attached and prevents leakage.

Referring to FIG. 3E, when the thicknesses of the film 160 for the COF and the film 170 for the FPC are different from each other according to another embodiment of the present invention, the film 160 for the COF and the FPC at the first pressure P1 are different. Simultaneously press the film for 170, and then press the film for COF 160 or FPC 170 thinner at a second pressure (P2).

For example, when the thickness of the COF film 160 is thicker than the FPC film 170 by the signal line of the COF film 160, the COF film 160 and the FPC film ( Simultaneously pressurizing the 170, the second pressure (P2) to press the thinner FPC film 170. Thereby, even if the thickness of the film 160 for COF and the film 170 for FPC differs, the indentation defect of the conductive ball in ACF 150 by the thickness difference can be prevented. As a result, the reliability of the organic light emitting display device can be improved.

Meanwhile, the COF film 160 is attached to both edges of the pad portion P of the display panel 110, and the FPC film 170 is attached to the display panel 110 between the COF films 160. . However, the present invention is not limited thereto. Subsequently, the printed circuit board (not shown) is conductively attached to the other side of the film 160 for COF and the film 170 for FPC, followed by final inspection to complete the organic light emitting display device.

 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 an organic light emitting display device according to an exemplary embodiment of the present invention.

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

2 is a flowchart illustrating a method of manufacturing an organic light emitting display device according to the present invention.

3A to 3E are diagrams for describing a method of manufacturing the OLED display illustrated in FIG. 1A.

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

110: display panel 1120: device substrate

140: sealing board 150: ACF

160: film for COF 170: film for FPC

Claims (10)

Preparing a display panel including an organic light emitting device module, the display unit configured to implement an image, and a pad unit configured to apply a driving signal to the display unit; Forming an ACF on one side of the pad part; Simultaneously aligning a film for COF and a film for FPC with the pad portion of the display panel; And Bonding the COF film and the FPC film to the pad part through the ACF by performing a pressing process on the COF film and the FPC film. The method of claim 1, wherein the film for COF and the film for FPC are formed to have the same thickness. The method of claim 1, wherein the film for COF and the film for FPC are formed of the same material. The method of claim 2, wherein the pressing process is performed by pressing the COF film and the FPC film at the same pressure. The method of claim 1, wherein the pressing step is a step of pressing the film for COF and the film for FPC at a first pressure, And pressurizing the COF film or the FPC film at a second pressure. 2. The method of claim 1, wherein the pressing step is a step of pressing the film for COF and the film for FPC at a first pressure, And pressurizing the FPC film at a second pressure. The method of claim 1, wherein a power signal is applied through the film for COF, And a scan signal and a data signal are applied through the FPC film.  A display panel including an organic light emitting diode module configured to display an image and a pad unit configured to apply a driving signal to the display unit; COF film and FPC film attached to one side of the pad portion; And And an ACF containing a conductive ball for electrically connecting the film for COF and the film for FPC to the display panel. The organic light emitting display device of claim 8, wherein the film for COF and the film for FPC are formed of the same material. The organic light emitting display device of claim 8, wherein a thickness of the film for COF and a thickness of the film for FPC are the same.

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