JP2008123700A - Organic el display device and repairing method therefor, and manufacturing method for the organic el display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an active-matrix type organic EL display device that can flows a current that can open destruct a defective part. <P>SOLUTION: The active-matrix type organic EL display device has a plurality of organic EL elements, respectively in which an organic light-emitting layer is sandwiched between a cathode electrode and an anode electrode. Each organic EL element is connected to each of a plurality of signal lines, each of a plurality of scanning lines, and each of a plurality of anode lines, respectively. A protrusion part is formed to the anode line, and the protruding part of the anode line and the anode electrode or an electrode, having the same potential as that of the anode electrode, are laminated across an insulating film. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention belongs to a technical field of an organic EL display device, a repair method thereof, and a method of manufacturing an organic EL display device.

  The organic EL display device has a structure in which an organic light emitting layer is sandwiched between an anode electrode and a cathode electrode. When the anode electrode and the cathode electrode are short-circuited, the organic EL element in that portion does not emit light. A lighting defect occurs.

  A method called aging is known as a method for repairing such non-lighting defects. In the manufacturing process of the organic EL element, an aging process is performed in which a voltage is applied between the anode electrode and the cathode electrode, so that the film defect portion is preliminarily broken open.

  For example, Patent Literature 1 and Patent Literature 2 disclose an aging method for an active matrix organic EL display device. FIG. 4 shows a circuit configuration of the pixel portion disclosed in the patent document. Each pixel includes a switching TFT, a driving TFT, an organic light emitting (EL) element, and a capacitor.

JP 2003-51384 A JP 2005-340149 A

  In an active matrix type organic EL display device, a drive circuit is constituted by a polysilicon TFT in order to control a minute current, and a current that can be supplied to the drive TFT is several μA. Therefore, a current required for open breakdown cannot be obtained, and a sufficient aging effect cannot be obtained.

  SUMMARY OF THE INVENTION In view of the above problems, the present invention has an object to provide an active matrix organic EL display device capable of passing an open breakable current to a defective portion, a repair method thereof, and a method of manufacturing the organic EL display device. To do.

As means for solving the problems of the background art, an organic EL display device according to the invention described in claim 1 is:
A plurality of organic EL elements each having an organic light emitting layer sandwiched between a cathode electrode and an anode electrode, and each organic EL element is connected to each of a plurality of signal lines, a plurality of scanning lines, and a plurality of anode lines. In an active matrix type organic EL display device connected to each other,
A protrusion is formed on the anode line, and the protrusion of the anode line and the anode electrode or an electrode having the same potential as the anode electrode are stacked with an insulating layer interposed therebetween.

  According to the present invention, the protrusion formed on the anode line and the anode electrode or the electrode having the same potential as the anode electrode are stacked with the insulating layer interposed therebetween. The laminated portion is irradiated with laser to connect the anode line and the cathode electrode. Thereafter, when a voltage is applied between the anode electrode and the cathode electrode to age the defect portion and open break, a current flows through the organic EL element without passing through the driving TFT. Therefore, a current can be passed without being restricted by the characteristics of the driving TFT, and the defective portion can be surely broken open.

  Hereinafter, embodiments of an organic EL display device, a repair method thereof, and a method of manufacturing an organic EL display device according to the present invention will be described with reference to the drawings. In addition, the well-known or well-known technique of the said technical field is applied regarding the part which is not illustrated or described in particular in this embodiment. Moreover, this embodiment is one embodiment of the invention, and is not limited thereto.

<First Embodiment>
First, the structure of the organic EL display device according to the present invention will be described along the manufacturing method.

A polysilicon layer 102 was formed on an insulating substrate 101 such as a glass substrate, and a gate insulating film 103 made of, for example, SiO ₂ was formed thereon (see FIG. 2). The thickness of the gate insulating film 103 is preferably 100 nm to 200 nm, and an oxide such as Ta ₂ O ₅ may be used in order to improve driving capability.

  On the gate insulating film 103, for example, a metal material such as Cr, MoW, or Al is formed by sputtering to form the gate electrode 104, the anode line 105, the gate line 107, and the gate electrode of the switching TFT 117. Then, a pattern was formed by a photoetching method or the like. At this time, the protrusion 106 is formed on the anode line 105, and the anode connection electrode 109 is laminated with the interlayer insulating film 108 interposed therebetween (see FIGS. 1 and 2). Note that the thickness of the gate electrode 104 and the anode line 105 is preferably 150 nm to 350 nm.

An interlayer insulating film 108 made of SiO ₂ or the like was formed so as to cover them, and a signal line 110 and an anode connection electrode 109 were formed thereon. As a result, the protrusion 106 of the anode line 105 has a laminated structure with the anode connection electrode 109 with the interlayer insulating film 108 interposed therebetween. In the repair process of the defective pixel, in order to connect the protrusion 106 of the anode line 105 and the anode connection electrode 109 by laser irradiation at this portion, the size of the stacked portion is 5 μm × 5 μm or more, and the interlayer insulating film The thickness of 108 is preferably 600 nm or less.

  Incidentally, in the above process, the signal line 110 is connected to the source electrode of the transistor through a through hole. As the material of the signal line 110, a laminated film such as Cr, MoW, Al or Mo / Al / Mo is used, and the thickness is preferably 300 nm to 800 nm in order to reduce the wiring resistance.

  A planarizing film 111 such as an acrylic resin is formed on the substrate by a spin coat method or the like in order to alleviate the unevenness of the transistors and wirings, and a through hole 112 for connecting the anode electrode 113 and the anode connection electrode 109 later is formed. Formed. In order to obtain sufficient flatness, the thickness of the planarizing film 111 is preferably 1 μm to 3 μm.

  An anode electrode 113 was formed on the planarizing film 111 and connected to the anode connection electrode 109 through the through hole 112. The anode electrode 113 is preferably a light-reflective member, and is preferably made of a material such as Cr, Al, Ag, Au, or Pt. This is because the higher the reflectance, the higher the light extraction efficiency.

  An element isolation film 114 was formed so as to cover the through hole 112 and the edge of the anode electrode 113.

  The organic light emitting layer 115 and the cathode electrode 116 were laminated on such a substrate by a known means to produce an organic EL element in each pixel region, thereby obtaining an organic EL display device.

  The organic light emitting layer 115 may be a plurality of layers, for example, a stacked layer of a hole transport layer, a light emitting layer, and an electron transport layer, or a hole injection layer, a hole transport layer, a light emitting layer, and an electron. It may be a laminate of a transport layer and an electron injection layer.

  The cathode electrode 116 is preferably a light-transmitting member, and is preferably made of a transparent conductive material such as ITO or IZO. Moreover, a semi-transmissive reflective member may be used. In this case, for example, a metal film having a thickness of about 1 nm to 60 nm is preferable.

  In the present invention, the light extraction direction may be either the lower electrode side or the upper electrode side. In the case where light is extracted from the lower electrode side, the lower electrode is preferably a light transmissive member, and the upper electrode is preferably a light reflective member, contrary to the above description.

  Next, a method for repairing the organic EL display device having the above configuration will be described.

  First, the entire surface of the organic EL display device having the above configuration is turned on to detect non-light emitting pixels. Next, a laser is applied to the laminated portion of the protrusion 106 of the anode line 105 and the anode connection electrode 109 of the detected pixel (see FIG. 3A). When the laser power is sufficiently high, the metal melts, the interlayer insulating film 108 is destroyed, and the protrusion 106 of the anode line 105 and the anode connection electrode 109 are connected (see FIG. 3B). ). Then, since the anode electrode 113 and the anode line 105 are directly connected without passing through the driving TFT 118, if a voltage is applied between the anode line 105 and the cathode electrode 116, a sufficient current can be supplied to the defective pixel. . Therefore, a current necessary for open breakdown of the defective portion is supplied to repair the defective pixel. Since the organic EL element is directly driven, an arbitrary voltage, current, and waveform can be applied, and defective pixels can be repaired efficiently.

  Next, the anode wire 105 and the protrusion 106 are cut by laser irradiation (see FIG. 3C). Then, the anode line 105 and the anode electrode 113 are electrically disconnected, and the repaired pixel operates in the same manner as a normal pixel (see FIG. 3D).

<Second Embodiment>
In the second embodiment, laser irradiation is used as a method for open destruction of defective pixels. In the step of FIG. 3B, when a current is passed between the cathode electrode 116 and the anode line 105, the defective portion generates heat. When this is observed with a thermoviewer or an infrared camera, a heat generation point can be specified. This heat generating portion is irradiated with a laser to open the defective portion.

  Thereafter, similarly to the first embodiment, the anode line 105 and the protrusion 106 are cut by laser irradiation (see FIG. 3C). Then, the anode line 105 and the anode electrode 113 are electrically disconnected, and the repaired pixel operates in the same manner as a normal pixel (see FIG. 3D).

1 is a schematic plan view showing an organic EL display device according to the present invention. It is a cross-sectional schematic diagram showing the structure between the A point and B point shown in FIG. It is a figure which shows the repair process of the defective pixel of the organic electroluminescence display which concerns on this invention. It is a figure which shows the prior art example of a pixel circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 Glass substrate 102 Polysilicon layer 103 Gate insulating film 104 Gate electrode 105 Anode line 106 Projection part 107 Gate line 108 Interlayer insulating film 109 Anode connection electrode 110 Signal line 111 Planarization film 112 Through hole 113 Cathode electrode 114 Element isolation film 115 Organic light emitting layer 116 Cathode electrode 117 Switching TFT
118 Driving TFT

Claims (4)

A plurality of organic EL elements each having an organic light emitting layer sandwiched between a cathode electrode and an anode electrode, and each organic EL element is connected to each of a plurality of signal lines, a plurality of scanning lines, and a plurality of anode lines. In an active matrix type organic EL display device connected to each other,
A projection is formed on the anode line, and the projection of the anode line and the anode electrode or the electrode having the same potential as the anode electrode are stacked with an insulating layer interposed therebetween, and the organic EL display apparatus. A plurality of organic EL elements each having an organic light emitting layer sandwiched between a cathode electrode and an anode electrode, and each organic EL element is connected to each of a plurality of signal lines, a plurality of scanning lines, and a plurality of anode lines. Each connected,
A projection is formed on the anode line, and the projection of the anode line and the anode electrode or the electrode having the same potential as the anode electrode of the active matrix type organic EL display device laminated with an insulating layer interposed therebetween A repair method,
Detecting the position of the organic EL element short-circuited between the cathode electrode and the anode electrode;
A step of irradiating a laser beam to the protruding portion of the anode line of the detected organic EL element and directly connecting the anode line and the anode electrode;
Applying a voltage to the anode line and the cathode electrode to open-break the defective portion;
Cutting the projection of the anode line by laser irradiation;
A method of repairing an organic EL display device, comprising: A plurality of organic EL elements each having an organic light emitting layer sandwiched between a cathode electrode and an anode electrode, and each organic EL element is connected to each of a plurality of signal lines, a plurality of scanning lines, and a plurality of anode lines. Each connected,
A projection is formed on the anode line, and the projection of the anode line and the anode electrode or the electrode having the same potential as the anode electrode of the active matrix type organic EL display device laminated with an insulating layer interposed therebetween A repair method,
Detecting the position of the organic EL element short-circuited between the cathode electrode and the anode electrode;
A step of irradiating a laser beam to the protruding portion of the anode line of the detected organic EL element and directly connecting the anode line and the anode electrode;
Applying a voltage to the anode line and the cathode electrode to generate heat at the defective portion;
Detecting heat or infrared rays emitted from the defective portion, irradiating the detection portion with a laser, and opening the defective portion; and
Cutting the projection of the anode line by laser irradiation;
A method of repairing an organic EL display device, comprising: A plurality of organic EL elements each having an organic light emitting layer sandwiched between a cathode electrode and an anode electrode, and each organic EL element is connected to each of a plurality of signal lines, a plurality of scanning lines, and a plurality of anode lines. In the manufacturing method of the active matrix type organic EL display device each connected,
In the step of forming the anode line, a protrusion is formed in advance on the anode line, and the anode electrode or the anode electrode and the electrode having the same potential are stacked with the protrusion of the anode line sandwiched between the insulating films. A method for manufacturing an organic EL display device.

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