KR20160055374A - Method for manufacturing organic light emitting display device - Google Patents

Abstract

The present invention relates to a method for manufacturing an organic light emitting display device including a dark-spotted pixel. The method includes a process of forming a pixel which includes an organic light emitting diode which comprises a switching thin film on a substrate, a driving thin film transistor connected to the switching thin film transistor, and a first and a second electrode connected to a driving thin film transistor; and a process of repairing a short error between the first electrode and the second electrode by applying a voltage to either the first electrode or the second electrode.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method of manufacturing an organic light-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing an organic light emitting display, and more particularly, to a method of repairing a shorted organic light emitting display.

The organic light emitting display device is a self-emission type display device, unlike a liquid crystal display device, a separate light source is not required, and thus it can be manufactured in a light and thin shape. Further, the organic light emitting display device is not only advantageous from the viewpoint of power consumption by low voltage driving, but also excellent in color implementation, response speed, viewing angle, and contrast ratio (CR), and is being studied as a next generation display.

Hereinafter, a description will be made of a case where a foreign matter flows in the manufacturing process of the OLED display device with reference to FIG. 1 is a cross-sectional view illustrating a process of introducing foreign matter into the organic light emitting display device.

Referring to FIG. 1, the OLED display includes an organic light emitting diode 40 including an anode electrode 42, an organic layer 43, and a cathode electrode 44. The organic light emitting diode 40 functions as a pixel of the OLED. However, the foreign material 60 may be introduced during the manufacturing process of the OLED display. Particularly, the foreign matter 60 that is introduced in the process of manufacturing the organic light emitting diode 40 often causes defective pixels. The organic layer 43 is formed on the anode electrode 42 by a vapor deposition process so that the organic layer 43 is deposited on the anode electrode 42 due to foreign substances when the foreign substance is present on the anode electrode 42. [ It may not be possible. That is, a hole may be formed in the organic layer 43 to expose a part of the upper surface of the anode electrode 42. Thereafter, a cathode electrode 44 is deposited. At the boundary of the above-described holes, the cathode electrode 44 may be in direct contact with the anode electrode 42. [ The cathode electrode 44 and the anode electrode 42 of the organic light emitting diode 40 are shorted and the current supplied to the organic light emitting diode 40 is supplied to the anode electrode 42 and the cathode electrode 44, Through the contact portion (S). Therefore, the corresponding pixel is dark-lit, and the organic light emitting diode loses its function as a pixel. As the dark-lit pixels increase, the production yield of the OLED display may also be lowered.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a method of manufacturing an organic light emitting display device using a process of repairing an organic light emitting display device including short- .

According to an aspect of the present invention, there is provided an organic light emitting diode including a switching thin film transistor, a driving thin film transistor connected to the switching thin film transistor, and an organic light emitting diode having a first electrode and a second electrode connected to the driving thin film transistor, Forming a pixel including the pixel; And a step of repairing a short defect between the first electrode and the second electrode by applying a voltage to one of the first electrode and the second electrode, .

According to the solution of the above-mentioned problems, the present invention has the following effects.

First, it is possible to easily repair the dark-lit pixels by a short circuit, thereby reducing the number of dark spots of the organic light emitting display device that can be generated in the manufacturing process.

Second, the repair yield of the organic light emitting display device can be improved by repairing darkened pixels to normal pixels.

Third, it is possible to prevent degradation of elements in the organic light emitting display device, which may occur in repair processing, and it is possible to apply the present invention without causing a reliability problem even in a GIP (gate-driver in panel) type.

In addition to the effects of the present invention mentioned above, other features and advantages of the present invention will be described below, or may be apparent to those skilled in the art from the description and the description.

1 is a cross-sectional view illustrating a process of introducing foreign matter into the organic light emitting display device.
2A and 2B are cross-sectional views illustrating a method of manufacturing an organic light emitting display according to an exemplary embodiment of the present invention.
3 is a schematic view of a repair device for eliminating a short circuit defect in the organic light emitting display according to an embodiment of the present invention.
4 is a circuit diagram showing a circuit operation of one pixel according to an embodiment of the present invention.
5 is a signal waveform diagram of one pixel according to an embodiment of the present invention.
6A and 6B are circuit diagrams showing circuit driving of one pixel according to another embodiment of the present invention.
7 is a signal waveform diagram of one pixel according to another embodiment of the present invention.
8 is a signal waveform diagram of one pixel according to another embodiment of the present invention.
9 is a schematic view of a repair device for eliminating a short circuit defect in an organic light emitting display according to another embodiment of the present invention.

The meaning of the terms described herein should be understood as follows.

The word " first, "" second," and the like, used to distinguish one element from another, are to be understood to include plural representations unless the context clearly dictates otherwise. The scope of the right should not be limited by these terms. It should be understood that the terms "comprises" or "having" does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof. It should be understood that the term "at least one" includes all possible combinations from one or more related items. For example, the meaning of "at least one of the first item, the second item and the third item" means not only the first item, the second item or the third item, but also the second item and the second item among the first item, Means any combination of items that can be presented from more than one. The term "on" means not only when a configuration is formed directly on top of another configuration, but also when a third configuration is interposed between these configurations.

Hereinafter, preferred embodiments of an aging device for an organic light emitting diode display according to the present invention will be described in detail with reference to the accompanying drawings. In the drawings, like reference numerals are used to denote like elements throughout the drawings, even if they are shown on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

2A and 2B are cross-sectional views illustrating a method of manufacturing an organic light emitting display according to an exemplary embodiment of the present invention.

2A, a driving thin film transistor Tdr is formed on a substrate 100, a planarization layer 160 is formed on the driving thin film transistor Tdr, A bank layer 210 is formed on the first electrode 200 and an organic layer 220 is formed on the first electrode 200. The organic layer 220 is formed on the first electrode 200, The second electrode 230 is formed.

The driving thin film transistor Tdr includes an active layer 110 formed on the substrate 100, a gate insulating layer 120 formed on the active layer 110, a gate insulating layer 120 formed on the gate insulating layer 120, A step of forming an electrode 130 and an interlayer insulating layer 140 on the gate electrode 130 and forming a source electrode 150a and a drain electrode 150b on the interlayer insulating layer 140 . The source electrode 150a and the drain electrode 150b are connected to the active layer 110 through a contact hole provided in the gate insulating layer 120 and the interlayer insulating layer 140, respectively. Although the top gate structure in which the gate electrode 130 is formed on the active layer 110 has been described in the drawing, the present invention is not necessarily limited thereto, and the gate electrode 130 may be formed under the active layer 110 Or may be formed with a bottom gate structure formed thereon.

A contact hole is formed in the planarization layer 160 such that the source electrode 150a of the driving TFT Tdr is exposed and the first electrode 200 is formed in the planarization layer 160 through a contact hole formed in the planarization layer 160. [ And is connected to the source electrode 150a. If the driving thin film transistor Tdr is of the P-type, the drain of the driving thin film transistor Tdr is connected to the planarization layer 160, A contact hole is formed to expose the electrode 150b and the first electrode 200 is connected to the drain electrode 150b through a contact hole formed in the planarization layer 160. [

As shown in the drawing, a foreign substance 300 may be formed on the first electrode 200 in the manufacturing process. In this case, in the region where the foreign substance 300 is formed, the first electrode 200, A short failure may occur between the first electrode 230 and the second electrode 230. That is, since the foreign material 300 covers the upper surface of the first electrode 200, the organic layer 220 and the second electrode 230 are formed on the upper surface of the foreign material 300 in the region where the foreign material 300 is formed So that the organic layer 220 contacting the upper surface of the first electrode 200 and the second electrode 230 formed thereon are cut off.

At this time, the second electrode 230 extends beyond the end of the organic layer 220 and contacts the first electrode 200, resulting in a short circuit between the second electrode 230 and the organic layer 220. The short defect between the first electrode 200 and the second electrode 230 may be eliminated through the process of FIG. 2B, which will be described later.

2B, when a voltage is applied between the first electrode 200 and the second electrode 230 to form the first electrode 200 and the second electrode 230 in the region where the foreign substance 300 is formed, The electrodes 230 are separated from each other.

More specifically, when a voltage is applied between the first electrode 200 and the second electrode 230, a contact area between the first electrode 200 and the second electrode 230, that is, Large heat is generated in the area. This is like the principle that sparks occur when two wires with potential difference are shorted to each other. When heat is generated in the shorted region as described above, the second electrode 230 is expanded due to heat and then cooled to be shrunk. As a result, the second electrode 230 and the first electrode 200 The second electrode 230 is rolled up in a direction away from the first electrode 200 while being separated from each other. The foreign material 300 may be removed in the process of being rolled up in a direction away from the first electrode 200. Accordingly, a hole H is formed in a region of the second electrode 230 that contacts the first electrode 200 in the pixel.

In order to separate the first electrode 200 and the second electrode 230 from each other, a voltage may be applied between the first electrode 200 and the second electrode 230 in various ways. Hereinafter, a method of applying a voltage between the first electrode 200 and the second electrode 230 will be described in more detail.

3 is a schematic view of a repair device for eliminating a short circuit defect in the organic light emitting display according to an embodiment of the present invention.

3, a plurality of pixels P are provided on a substrate 100 for an organic light emitting diode display, in which a plurality of gate lines GL and a plurality of data lines DL intersect each other. Each of the plurality of pixels P is connected to the driving power supply line PL and the cathode electrode CE. The driving power line PL is connected to the source electrode 150a of the driving thin film transistor Tdr of FIG. 2 and the cathode electrode CE corresponds to the second electrode 230 of FIG. do.

In addition, a repair pad region is provided outside the pixel region provided with the plurality of pixels (P). A repair gate pad portion 410, a repair data pad portion 420, a repair driving power pad portion 430, and a repair cathode power pad portion 440 are formed in the repair pad region.

The repair gate pad portion 410 is connected to the plurality of gate lines GL through a gate shorting bar SB_G. The repairing gate pad unit 410 may receive a gate voltage from the repair signal supply unit 500 and supply the gate voltage to the plurality of gate lines GL. The repair gate pad portion 410 and the gate shorting bar SB_G are removed later so that the plurality of gate lines GL are separated from each other.

The repair data pad unit 420 is connected to the plurality of data lines DL through a data indicating bar SB_D. The repair data pad unit 420 may receive the data voltage from the repair signal supply unit 500 and supply the data voltage to the plurality of data lines DL. The repair data pad unit 420 and the data saving bar SB_D are removed later, so that the plurality of data lines DL are separated from each other.

The repair drive power supply pad unit 430 is connected to the drive power supply line PL. Since the common voltage is applied to the driving power line PL, it is not necessary to connect the repair driving power pad unit 430 to the driving power line PL through a separate shorting bar. The repair drive power supply pad unit 430 may receive the pixel drive power supply EVDD from the repair signal supply unit 500 and supply the drive power supply line PL.

The repairing cathode power pad unit 440 is connected to the cathode electrode CE. Since the cathode electrode CE is applied with a common voltage, it is not necessary to connect the repairing cathode power pad unit 440 to the cathode electrode CE through a separate shorting bar. The repair cathode power supply pad unit 440 may supply the cathode power supply EVSS to the cathode electrode CE from the repair signal supply unit 500.

The repair signal supply unit 500 is connected to the repair gate pad unit 410, the repair data pad unit 420, the repair drive power supply pad unit 430, and the repair cathode power supply pad unit 440, Signals are supplied to repair the short defects between the first electrode 200 and the second electrode 230 due to the foreign substances 300 described above in each of the plurality of pixels P. [ That is, the repair signal supply unit 500 may supply a gate voltage to the repair gate pad unit 410, a data voltage to be supplied to the repair data pad unit 420, ) Between the first electrode 200 and the second electrode 230 by controlling the pixel driving power supply EVDD for supplying the pixel power supply unit 440 to the pixel power supply unit 440 and the cathode power supply EVSS for supplying the pixel power supply unit 440 for the repair, ) Defects can be repaired, which will be described with reference to a driving method of individual pixels. As shown in the figure, the repair signal supply unit 500 is configured as an apparatus outside the substrate 100, and is not included in the configuration of the final OLED display.

4 is a circuit diagram showing circuit driving of one pixel according to an embodiment of the present invention, which relates to circuit driving of one pixel for repairing a short defect between a first electrode and a second electrode.

4, the pixel P according to an exemplary embodiment of the present invention includes a switching thin film transistor Tsw, a driving thin film transistor Tdr, a capacitor Cst, and an organic light emitting diode OLED .

The switching thin film transistor Tsw is connected to the gate line GL and the data line DL, respectively. The switching thin film transistor Tsw supplies the data voltage Vdata supplied to the data line DL to the gate electrode of the driving thin film transistor Tdr according to the gate signal GS supplied to the gate line GL .

The driving thin film transistor Tdr is connected to the switching thin film transistor Tsw, the driving power supply line PL, and the organic light emitting diode OLED. The driving thin film transistor Tdr controls the amount of current flowing from the driving power supply line PL to the organic light emitting diode OLED according to the data voltage Vdata supplied from the switching thin film transistor Tsw.

The capacitor Cst is connected between the gate electrode and the source electrode of the driving transistor Tdr.

The organic light emitting diode OLED includes an anode electrode AE connected to the driving thin film transistor Tdr and a cathode electrode CE connected to a cathode power source EVSS.

In the case of one pixel according to an embodiment of the present invention, the gate signal GS and the data voltage Vdata are continuously supplied during the repair period. Therefore, the switching thin film transistor Tsw is always kept on during the repair period, so that the data voltage Vdata is always applied to the gate terminal of the driving thin film transistor Tdr. In this situation, when a voltage difference is generated between the anode electrode AE and the cathode electrode CE of the organic light emitting diode OLED, the short defects can be repaired in the same manner as in FIG. 2B described above. The anode electrode AE corresponds to the first electrode 200 shown in FIG. 2B and the cathode electrode CE corresponds to the second electrode 230 shown in FIG. 2B.

Fig. 5 is a signal waveform diagram in one pixel according to an embodiment of the present invention, which relates to the circuit driving according to Fig. 4 described above.

As can be seen from Fig. 5, the gate signal GS and the data voltage Vdata are continuously supplied during the repair period (T). During the repair period T, the pixel drive power supply EVDD is swung between the first voltage V1 and the second voltage V2 which is lower than the first voltage V1, 1 voltage V1 and a voltage difference is generated between the pixel drive power source EVDD and the cathode power source EVSS.

4 and 5, for example, the data voltage Vdata synchronized with the gate signal GS is supplied at 5 V, the voltage supplied to the driving power supply line PL swings between 0 V and -25 V, As a result, when the cathode power source EVSS supplied to the cathode electrode CE is maintained at 0V, the gate-source voltage Vgs supplied to the driving transistor Tdr during the repairing process becomes 30V. Therefore, there is a possibility that a problem of element deterioration of the driving transistor Tdr may occur during the repair process.

4 and 5 described above, since the gate signal GS and the data voltage Vdata are continuously supplied during the repair period T, the gate-source voltage Vdata of the drive thin film transistor Tdr Vgs) is increased and there is a possibility of device deterioration. Therefore, in order to reduce the possibility of deterioration of the driving thin film transistor Tdr, it may be preferable that the gate signal GS and the data voltage Vdata are not continuously supplied during the repair period T. Hereinafter, same.

6A and 6B are circuit diagrams showing circuit driving of one pixel according to another embodiment of the present invention.

The configuration of the circuit according to Figs. 6A and 6B is the same as that of the circuit of Fig. 4 described above, but differs in the driving of the circuit.

6A corresponds to the initial period of the repair period T. During the initial period, the gate signal GS and the data voltage Vdata synchronized with the gate signal GS are supplied, but the pixel drive power source EVDD A voltage difference does not occur between the cathode power sources EVSS. Therefore, the supplied data voltage Vdata is stored in the capacitor Cst.

6B is a diagram showing a state in which the gate signal GS and the data voltage Vdata are not supplied during the latter period and the voltage Vdata is applied between the pixel drive power source EVDD and the cathode power source EVSS There is a difference. Thus, a voltage difference is generated between the anode electrode AE and the cathode electrode CE of the organic light emitting diode OLED, and the short defects can be repaired in the same manner as in FIG. 2B described above.

Fig. 7 is a signal waveform diagram in one pixel according to another embodiment of the present invention, which relates to the circuit driving according to Figs. 6A and 6B described above.

7, a data voltage Vdata synchronized with the gate signal GS and the gate signal GS is supplied during the first repair period T1 corresponding to the initial period, and the pixel drive power source EVDD is supplied with the data voltage Vdata, And the cathode power source EVSS maintain the first voltage V1 so that no voltage difference is generated between the pixel drive power source EVDD and the cathode power source EVSS. Thereafter, the gate signal GS and the data voltage Vdata are not supplied during the second repair period T2 corresponding to the latter period, and the pixel drive power source EVDD is supplied with the first voltage V1 and the first voltage V2, A second voltage V2 lower than the first voltage V1 while the cathode power source EVSS maintains the first voltage V1 so that a voltage difference is generated between the pixel drive power source EVDD and the cathode power source EVSS.

7, for example, a data voltage Vdata synchronized with the gate signal GS is supplied at 5 V, a voltage of 5 V is stored in the capacitor Cst, and a voltage supplied to the driving power supply line PL is 0 V Assuming that the cathode power source EVSS supplied to the cathode electrode CE is maintained at 0 V, the voltage applied to the gate terminal of the driving thin film transistor is the voltage of the voltage supplied to the driving power source line PL It is affected and swings between 5V and -20V. As a result, the value of the gate-source voltage Vgs supplied to the driving transistor Tdr at the time of the repair process can be reduced to 5V. More specifically, when the voltage supplied to the driving power supply line PL is 0V, the voltage applied to the gate terminal of the driving thin film transistor becomes 5V and the gate-source voltage (Vgs) value becomes 5V. When the voltage supplied to the driving power supply line PL is -25 V, the voltage applied to the gate terminal of the driving thin film transistor becomes -20 V and the gate-source voltage Vgs ) Value becomes 5V. As a result, there is an effect of avoiding the problem of element deterioration of the driving transistor Tdr.

Fig. 8 is a signal waveform diagram in one pixel according to another embodiment of the present invention, which relates to the circuit driving according to Figs. 6A and 6B described above.

8, the gate signal GS and the data voltage Vdata are supplied during the first repair period T1 corresponding to the initial period and the pixel drive power supply EVDD and the cathode power supply EVSS are supplied to the fourth A voltage difference does not occur between the pixel drive power supply EVDD and the cathode power supply EVSS by maintaining the voltage V4. Thereafter, the gate signal GS and the data voltage Vdata are not supplied during the second repair period T2 corresponding to the latter period, the pixel drive power supply EVDD maintains the fourth voltage V4, The voltage difference EVSS swings between the fourth voltage V4 and the third voltage V3 higher than the fourth voltage V4 so that a voltage difference is generated between the pixel driving power source EVDD and the cathode power source EVSS.

9 is a schematic diagram of a repair device for eliminating a short circuit defect in an organic light emitting diode display according to another embodiment of the present invention, except that a gate built-in circuit (GIP) is added instead of a gate shorting bar SB_G. 3 is the same as the repair apparatus according to Fig. Therefore, the same reference numerals are assigned to the same components, and only the different components will be described below.

9, since the gate internal circuit (GIP) 415 is added according to another embodiment of the present invention, the gate signal GS (from the repair signal supply unit 500 to the repair gate pad unit 410) The supplied gate signal GS is supplied to the plurality of pixels P via the gate built-in circuit (GIP) Therefore, the gate signal GS can be sequentially supplied to the plurality of gate lines GL corresponding to each of the plurality of pixels P, respectively. 3, the gate signal GS is simultaneously supplied to the plurality of gate lines GL. However, in the repair apparatus according to FIG. 9, the gate signal GS is sequentially supplied to the plurality of gate lines GL. ) Can be supplied.

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 general inventive concept as defined by the appended claims and their equivalents. Will be clear to those who have knowledge of. Therefore, the scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be interpreted as being included in the scope of the present invention.

100: substrate 200: first electrode
230: second electrode 300: foreign matter
410: repair gate pad portion 415: gate built-in circuit
420: repair data pad unit 430: repair power supply pad unit for repair
440: Cathode power supply pad unit for repair 500: Signal supply unit for repair

Claims (10)

Forming a pixel including a switching thin film transistor on the substrate, a driving thin film transistor connected to the switching thin film transistor, and an organic light emitting diode having a first electrode and a second electrode connected to the driving thin film transistor; And
And applying a voltage to any one of the first electrode and the second electrode to repair short defects between the first electrode and the second electrode. The method according to claim 1,
Wherein the step of applying a voltage to one of the first electrode and the second electrode comprises:
Turning on the switching thin film transistor;
Applying a voltage swinging between a first voltage and a second voltage to either one of the first electrode and the second electrode; And
And applying a first voltage to the other one of the one electrode and the second electrode. 3. The method of claim 2,
Applying a voltage swinging between a first voltage and a second voltage to one of the first electrode and the second electrode; and applying a voltage swinging between the first electrode and the second electrode, Wherein the step of applying the first voltage to the other one of the electrodes is continuously performed during the repair process. 3. The method of claim 2,
Wherein the repair process includes a first repair process period and a second repair process period,
Wherein the step of turning on the switching thin film transistor is performed during the first repair process period,
Wherein the step of applying a voltage swinging between the first voltage and the second voltage to one of the first electrode and the second electrode is performed during the second repair process period,
Wherein the step of applying the first voltage to the other one of the one electrode and the second electrode is performed during the first repair process period and the second repair process period. 5. The method of claim 4,
And the switching thin film transistor is turned off during the second repair process period. 6. The method of claim 5,
Wherein a data voltage supplied from the switching thin film transistor is stored in a capacitor during the first repair process period and a data voltage stored in the capacitor is supplied to the drive thin film transistor during the second repair process period . 5. The method of claim 4,
Wherein the first voltage is applied to both the first electrode and the second electrode during the first repair process period. The method according to claim 1,
Wherein the step of repairing a short defect between the first electrode and the second electrode includes a step of forming a hole in the second electrode region in contact with the first electrode in the pixel . The method according to claim 1,
Wherein a plurality of the pixels are formed, and the plurality of pixels are connected to a gate built-in circuit. 10. The method of claim 9,
Wherein the step of applying a voltage to one of the first electrode and the second electrode includes a step of sequentially supplying a gate signal to each of the plurality of pixels in the gate built-in circuit .

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