JP2005243571A - Manufacturing methods of substrate for organic el display element and organic el display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate for an organic EL display element in which an unnecessary region can be made small and the positioning mark for cutting apart can be formed without generating the unnecessary region, and a manufacturing method of the organic EL display element. <P>SOLUTION: The substrate for organic EL display element comprises a plurality of organic EL display elements having a positive electrode wiring 1, an organic EL layer, and a negative electrode wiring 2. The positive electrode wiring 1 is connected to a common wiring for positive electrode 3 through a positive electrode connection wiring 5. Then, the negative electrode wiring 2 is connected to a common wiring for negative electrode 4 through a negative electrode connection wiring 6. A positioning mark 9 for cutting apart the plurality of organic EL display elements is formed on the common wiring for positive electrode 3 and/or the common wiring for negative electrode 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic EL (Electro Luminescence) display element substrate and an organic EL display element manufacturing method, and more particularly to an organic EL display element substrate and an organic EL display element manufacturing method capable of performing efficient aging treatment. About.

  An organic EL display device using an organic EL light emitting element has a wider viewing angle than a liquid crystal display device, and has a high response speed. ing. The organic EL display element constituting the organic EL display device has an anode formed on a substrate, a thin-film organic compound (organic EL layer) including a light emitting layer is laminated on the anode, and further on the organic EL layer. Further, a cathode is formed so as to face the anode formed on the substrate. The organic EL display element is a current-driven display element that emits light when a current is supplied to an organic EL layer disposed between an anode and a cathode that are provided to face each other. Since the organic EL display element has characteristics similar to those of a semiconductor light emitting diode, it is sometimes called an organic LED.

  The organic EL display element emits light when the anode side is set to the high voltage side, a predetermined voltage is applied between both electrodes, and a current is supplied to the organic EL layer. Conversely, when the cathode side is set to a high potential, no current flows and no light is emitted. When a constant voltage is applied to the organic EL layer of the organic EL display element, the light emission luminance greatly varies depending on a change in temperature or a change with time. Therefore, when driving an organic EL display element, a constant current driving method is generally used. That is, in order to obtain a predetermined light emission luminance, a constant current is supplied to the organic EL display element using a drive circuit having a constant current circuit.

  A plurality of anode wirings connected to the anode on the glass substrate or forming the anode itself in parallel, and connected to the cathode or forming the cathode itself in a direction perpendicular to the anode wiring An organic EL display element having a structure in which wirings are arranged in parallel and an organic EL layer is held between both electrodes is realized. In the organic EL display element in which the anode wiring and the cathode wiring are arranged in a matrix, the intersection of the anode wiring and the cathode wiring is a pixel. That is, the pixels are arranged in a matrix. In general, the cathode wiring is formed of metal, and the anode wiring is formed of a transparent conductive film such as ITO (indium / tin / oxide).

  When an organic EL display element in which anode wiring and cathode wiring are arranged in a matrix is driven by a simple matrix driving method, one of anode wiring and cathode wiring is used as a scanning electrode, and the other is used as a data electrode. . Then, a scan electrode driving circuit including a constant voltage circuit is connected to the scan electrode, and the scan electrode is driven at a constant voltage. Then, one of the scan electrodes is sequentially scanned every predetermined period to be in a selected state, and the other scan electrodes are in a non-selected state. In general, scanning is performed from a scanning electrode located at one end of a plurality of scanning electrodes arranged in parallel toward a scanning electrode located at the other end, and all the scanning electrodes are performed during a certain period. Are sequentially selected.

  A data electrode driving circuit having a constant current circuit at the output stage is connected to the data electrode. Then, a current corresponding to the display data of the row corresponding to the scan electrode in the selected state is supplied to each data electrode in synchronization with the scan. The current supplied from the constant current circuit to the data electrode flows to the scan electrode in the selected state through the organic EL layer located at the intersection of the scan electrode and the data electrode in the selected state. A pixel in the organic EL display element emits light in a period in which a scan electrode forming the pixel is in a selected state and a current is supplied from the data electrode. Further, when the supply of current from the data electrode is stopped, the light emission is also stopped. When driving, the anode wiring of the organic EL display element may be a scanning electrode or a data electrode.

  When the organic EL display element is driven with a constant current, the luminance decreases with time. The higher the initial luminance, the larger the rate of luminance decrease. For example, if the initial luminance is doubled, the time until the luminance is halved is approximately half. The reduction in luminance of the organic EL display element leads to reduction in luminance in an organic EL display device formed by incorporating a drive circuit or the like into the organic EL display element. Furthermore, the longer the pixel that has been emitting light, the darker it is, which causes a phenomenon that the luminance varies depending on the pixel. This phenomenon is called “burn-in”. If adjacent pixels have a luminance difference of about 3 to 5%, it is visually recognized that there is a luminance difference.

Due to technological development, the luminance half-life of the organic EL display element reaches several tens of thousands of hours at an initial luminance of about 100 cd / m ² , but burn-in occurs with a luminance drop of about 3 to 5%. It will occur in a hundred hours. This is a disadvantage with respect to other flat panel type display devices such as a liquid crystal display device.

  In many cases, the luminance of the organic EL display element is greatly reduced in the initial stage due to energization, and then gradually decreases. In the case where the luminance is so reduced, if the organic EL display element is driven for a while to reduce the luminance to a new initial state, the subsequent reduction method becomes gentle. The process of driving the organic EL display element for a while and reducing the luminance before the organic EL display device using the organic EL display element is actually used is called an aging process.

  As the aging treatment, for example, the anode wirings of the organic EL display element are short-circuited with a lead wire and connected to the voltage application device, and the cathode wirings are short-circuited with a lead wire and connected to the voltage application device. Then, a voltage pulse is applied from the voltage application device between the lead wire connecting the anode wiring person and the lead wire connecting the cathode wirings.

  On the other hand, due to dust, dust or the like generated when forming a thin film of an electrode or an organic EL layer, a defective portion may occur in the electrode or the organic EL layer. In the organic EL display element, since the organic EL layer between the electrodes is extremely thin, even if the defective portion is minute, current is easily concentrated, and the anode wiring and the cathode wiring are short-circuited. There is a problem that it leads to deterioration and non-light emission.

By using the above-described aging process, such a defective portion can be removed (see, for example, Patent Document 1). The short-circuit portion of the defective portion is destroyed by Joule heat generated during the aging process. Although the destroyed defective portion becomes a local non-light emitting portion, the defective portion is originally a minute one that cannot be visually recognized, and does not affect the display quality.
JP 61-114493 A

  Generally, a plurality of organic EL display elements are formed simultaneously on a single glass substrate by dividing them individually. At this time, the lead wire for connecting the anode wirings of the organic EL display elements and the lead wire for connecting the cathode wirings are located in a region between the divided organic EL display elements, that is, the divided organic EL display elements ( Cell).

  For this reason, it is necessary to provide a certain region in order to form the lead wire between the organic EL display elements on the glass substrate before division, and there is a problem in that the area efficiency is lowered.

  In addition, in order to divide the glass substrate, it is necessary to form a dividing positioning mark on the glass substrate because of the necessity of alignment.

  The present invention has been made to solve such problems, and one object of the present invention is to provide an organic EL display element substrate and an organic EL display element manufacturing method capable of reducing unnecessary regions. Is to provide. Another object of the present invention is to provide an organic EL display element substrate and an organic EL display element manufacturing method capable of forming a positioning mark for alignment without generating an unnecessary region. .

  An organic EL display element substrate according to the present invention includes a plurality of organic EL display elements having an anode wiring, an organic EL layer, and a cathode wiring, and the anode wiring and anode connection wiring in the plurality of organic EL display elements. A substrate for an organic EL display element, comprising: a connected anode common line; a cathode line in the plurality of organic EL display elements; and a cathode common line connected via the cathode connection line. Positioning marks for dividing a plurality of organic EL display elements are formed on the anode common wiring and / or the cathode common wiring. According to such a configuration, the organic EL display element can be accurately divided based on the positioning mark. In particular, since the positioning marks are formed on the anode common wiring and / or the cathode common wiring, it is not necessary to provide a dedicated area for forming the positioning marks, so that the area efficiency can be improved.

  Here, the positioning mark is preferably formed by an opening in the wiring.

  Further, it is preferable that a dividing line for dividing the plurality of organic EL display elements is provided on the anode common wiring and / or the cathode common wiring. With such a configuration, the area efficiency can be further increased.

  The organic EL display element manufacturing method according to the present invention includes a step of forming a plurality of organic EL display elements having an anode wiring, an organic EL layer, and a cathode wiring on a substrate, and an anode in the plurality of organic EL display elements. The anode connection wiring connected to the wiring, the anode common wiring connected to the anode connection wiring, the cathode connection wiring connected to the cathode wiring in the plurality of organic EL display elements, and the cathode connection Forming a cathode common wiring connected to the wiring, applying an aging voltage to the anode common wiring and the cathode connection wiring, and each organic EL display element after applying the voltage To separate all or part of the common wiring for anode and the common wiring for cathode to remain in the organic EL display element. A. According to such a method, generation of unnecessary portions can be suppressed, so that area efficiency can be improved.

  Here, in the step of dividing the organic EL display element, it is preferable to divide the anode common wiring and / or the cathode common wiring.

  Another method of manufacturing an organic EL display element according to the present invention includes a step of forming a plurality of organic EL display elements having an anode wiring, an organic EL layer, and a cathode wiring on a substrate, and the plurality of the organic EL display elements. The anode connection wiring connected to the anode wiring, the anode connection wiring connected to the anode connection wiring and having the dividing positioning mark formed thereon, and the cathode wiring in the plurality of organic EL display elements Forming a cathode connection wiring and a cathode common wiring connected to the cathode connection wiring; applying an aging voltage to the anode common wiring and the cathode connection wiring; And a step of dividing the organic EL display element based on at least the positioning mark after voltage application.

  Another method of manufacturing an organic EL display element according to the present invention includes a step of forming a plurality of organic EL display elements having an anode wiring, an organic EL layer, and a cathode wiring on a substrate, and the plurality of the organic EL display elements. Anode connection wiring connected to the anode wiring, a common wiring for anode connected to the anode connection wiring and having a first positioning mark formed thereon, and cathodes in the plurality of organic EL display elements Forming a cathode connection wiring connected to the wiring, a cathode common wiring connected to the cathode connection wiring and having a second positioning mark for separation, and the anode common wiring; Applying a voltage for aging to the cathode connection wiring; and, after applying the voltage, the organic EL display element is connected to the first positioning mark and the second positioning mark. It is obtained by a step of dividing based on.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the organic EL display element substrate which can reduce an unnecessary area | region, and an organic EL display element can be provided. Furthermore, it is possible to provide an organic EL display element substrate and a method for manufacturing the organic EL display element that can form a positioning mark for dividing without generating an unnecessary region.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view for explaining an example of a method for manufacturing an organic EL display device. FIG. 2 is a perspective view for explaining an example of the manufacturing method of the organic EL display device.

  As shown in FIGS. 1 and 2, a large number of organic EL display elements each including a display region 7 are formed on one glass substrate 8. Each anode line 1 in each organic EL display element is connected to a first common line 3 as an anode common line by an anode connection line 5 as an anode connection member. Therefore, the same signal can be supplied from the first common wiring 3 to each anode wiring 1 in all organic EL display elements.

  Each cathode wiring 2 in each organic EL display element is connected to a second common wiring 4 as a cathode common wiring by a cathode connection wiring 6 as a cathode connecting member. Therefore, the same signal can be supplied from the second common wiring 4 to each cathode wiring 2 in all organic EL display elements. In FIG. 2, the first common wiring 3 is indicated by a broken line, and the second common wiring 4 is indicated by a solid line.

  FIG. 3 is an explanatory diagram showing a connection portion between the anode wiring 1 and the first common wiring 3. As shown in FIG. 3, the anode wiring 1 and the first common wiring 3 are connected by an anode connection wiring 5 having a narrower line width than them. Similarly, the cathode wiring 2 and the second common wiring 4 are connected by a cathode connection wiring 6 having a narrower line width than them.

  FIG. 4 is a process diagram for explaining an example of a method for manufacturing an organic EL display device. In the process shown in FIG. 4, each organic EL display element includes an organic EL element forming process for forming a wiring group and an organic EL layer on one glass substrate 8, and glass or the like for protecting the organic EL layer from moisture or the like. The organic EL display element is separated from the outside air by the opposite substrate, the aging process is performed for aging the organic EL display element, and the glass substrate 8 is divided into a plurality of organic EL display elements. An organic EL display device that is manufactured through a separation process that separates and an optical film application process that attaches an optical film such as a circularly polarizing plate to prevent reflection, and a mounting process that mounts peripheral circuits such as a drive circuit. Is produced.

  In the organic EL display element forming step, ITO is formed on the glass substrate 8, and the ITO is etched to form the anode wiring 1, the anode connection wiring 5, and the cathode connection wiring 6.

  Next, a metal film is formed, and the metal film is etched to form the lead wiring, the first common wiring 3 and the second common wiring 4 in each organic EL display element.

  On top of that, an insulating film is applied, and exposure development is performed to form an opening to be a light emitting portion of each pixel. Furthermore, an organic thin film as an organic EL layer is laminated thereon. As the organic thin film, a first hole transport layer, a second hole transport layer, a light emitting layer, and a cathode interface layer are sequentially formed. Finally, as the cathode wiring 2, a scanning electrode is formed of a metal such as aluminum and connected to the cathode lead wiring.

  FIG. 5 shows a top view of the organic EL display element before division. As shown in the figure, the first common wiring 3 extends substantially vertically, and a plurality of anode connection wirings 5 extend substantially vertically from the extending portion toward the adjacent display region 7. . The plurality of anode connection wirings 5 are connected to the anodes of adjacent organic EL display elements.

  Further, the second common wiring 4 is arranged in parallel with the first common wiring 3. The extending portion extending substantially vertically from the second common wiring 4 is routed to the vicinity of the anode connection wiring 5. A plurality of cathode connection wirings 6 extend toward the display region 7 from the vicinity of the tip of the extending portion of the second common wiring 4.

  In this example, a division positioning mark (alignment mark) 9 is provided on the first common wiring 3 to be used for alignment of the division in the division process. The positioning mark is a negative shape of the first common wiring 3. That is, in the first common wiring 3, the positioning mark 9 is formed by the shape of the area (opening) where there is no wiring. The positioning mark 9 is provided, for example, so as to sandwich the dividing line. The positioning mark 9 is formed by applying an insulating film on the first common wiring 3 and performing exposure development and the like.

  When the organic EL element forming step is completed, each anode wiring 1 in the plurality of simple matrix type organic EL display elements formed on the glass substrate 8 is formed on the glass substrate 8 via the anode connection wiring 5. A structure in which each cathode wiring 2 in the plurality of organic EL display elements is electrically connected to the second common wiring 4 via the cathode connection wiring 6 on the glass substrate 8. A substrate for an organic EL display device is formed.

  In the sealing step, another glass substrate as the second substrate is opposed to the glass substrate 8 in order to protect the organic EL layer formed on the glass substrate 8 in the organic EL element forming step from moisture. It arrange | positions and both glass substrates are joined by the peripheral sealing material as a gap | interval material. Then, dry nitrogen gas is sealed in the sealed space formed by the two glass substrates and the peripheral sealing material.

  Next, an aging process is performed before the dividing process. In the aging process executed in the aging process, an aging voltage application device is applied to the first common wiring 3 and the second common wiring 4 in order to perform the energization processing for aging on the anode wiring 1 and the cathode wiring 2. Connecting. In the aging step, the energization process is performed by setting the ambient temperature of the glass substrate 8 on which the plurality of organic EL display elements are formed to a room temperature or higher, preferably 80 ° C. or higher. By performing the energization process at a high temperature, a desired luminance can be reduced in a short time. The temperature at which the energization treatment is performed is preferably as high as possible within a range in which the organic EL display element is not deteriorated. Even if the temperature is high, since the process is performed in a process prior to the optical film application process for applying an optical film such as a circularly polarizing plate, the optical film is not adversely affected by heat.

Further, in order to reduce the desired luminance in a shorter time, the energization conditions are set so that the luminance of each pixel in the aging process is higher than the luminance when the rated display operation is performed as the organic EL display device. Set. For example, luminance level of the organic EL display device as long as 200 cd / ^{m 2,} is energized to emit light at 400 cd / ^{m 2.} By emitting light with a luminance twice as high as the luminance specification as the organic EL display device, the aging process is completed in about half the time compared to when aging is performed with the luminance specification as the organic EL display device.

Further, in the aging process, static driving (1/1 duty) is performed in which the anode wiring 1 and the cathode wiring 2 are always energized. At this time, it is not necessary to make the current density higher than the current density when operating as an organic EL display device. For example, the current density of the organic EL display device for multiplex driving at 1/50 duty is a 300 mA / cm ^2, if 12 mA / cm ² at static drive for aging, because the time average of the brightness is doubled It is. By the aging process, the defective portion where the anode wiring 1 and the cathode wiring 2 are short-circuited is destroyed and removed.

  When the aging process is completed, a dividing process is performed. In the dividing step, a dividing line is set so as to surround the display area 7. In FIG. 5, A1-A1 'and A2-A2' are dividing lines of the display surface side substrate, and B1-B1 'is a dividing line of the back surface side substrate. The dividing lines A1-A1 ', A2-A2', B1-B1 'intersect with the anode connection wiring 5 and the cathode connection wiring 6, respectively, and are arranged so as to divide each wiring.

  In the figure, C1-C1 'and C2-C2' are common dividing lines of the display surface side substrate and the back surface side substrate. As shown in FIG. 5, the dividing line C <b> 1-C <b> 1 ′ and the dividing line C <b> 2-C <b> 2 ′ are arranged on the first common wiring 3.

  Along the dividing line, the glass substrate 8 is divided into a plurality of organic EL display elements. That is, each anode wiring 1 and each cathode wiring 2 are separated from the first common wiring 3 and the second common wiring 4. The first common wiring 3 and the second common wiring 4 remain in the organic EL display element after the dividing step. By arranging the dividing lines in this way, it is possible to suppress the generation of unnecessary regions and increase the area efficiency. Further, the dividing lines C1-C1 ′ and C2-C2 ′ are arranged between the first common wiring 3 and the second common wiring 4, and the positioning mark 9 is arranged between the first common wiring 3 and the second common wiring 4. Each may be formed on the wiring 4.

  Next, in the optical film attaching step, an optical film such as a circularly polarizing plate is attached to the organic EL display element to prevent reflection. Then, in the mounting process, peripheral circuits such as a drive circuit are mounted on each organic EL display element to obtain an organic EL display device.

  As described above, in the present embodiment, a plurality of organic EL display elements can be energized at once in the aging process. As a result, the labor for performing the aging process is reduced. Moreover, since an aging process is implemented before an optical film sticking process, an aging process can be implemented in a high temperature environment.

  In the present embodiment, in the organic EL element forming step, ITO of a transparent conductive film is formed on the glass substrate 8, and the ITO is etched to etch the anode wiring 1 and the anode connection wiring 5 as the anode connection member. In addition, a cathode connection wiring 6 as a cathode connection member is formed. Next, a metal film is formed, and the metal film is etched to form a first common wiring 3 as an anode common wiring and a second common wiring 4 as a cathode common wiring. Further, an organic EL layer is laminated, and finally a metal cathode wiring 2 is formed. Metal is used as the common wiring for the anode and the common wiring for the cathode, and the transparent conductive film is used as the connecting member for the anode and the connecting member for the cathode. The connecting member for the anode and the connecting member for the cathode are connected to the anode wiring. It can be formed simultaneously when 1 is formed. Further, before the organic EL layer is laminated, the common anode wiring and the common cathode wiring can be formed at the same time.

  For example, the first common wiring 3 and the second common wiring 4 preferably have a wiring width of 200 μm or more because low resistance is obtained. In consideration of the occupied area on the glass substrate 8 (occupied area in the part to be cut off and occupied area in the part where the peripheral sealing material is installed) and the like, it is preferably 3 mm or less. The first common wiring 3 and the second common wiring 4 are made of metal such as molybdenum, silver, copper, aluminum, or chromium in order to reduce resistance.

It is a top view for demonstrating an example of the manufacturing method of the organic electroluminescent display apparatus concerning this invention. It is a perspective view for demonstrating an example of the manufacturing method of the organic electroluminescent display apparatus concerning this invention. It is explanatory drawing which shows the connection part of the anode wiring and 1st common wiring of the organic electroluminescent display apparatus concerning this invention. It is process drawing for demonstrating an example of the manufacturing method of the organic electroluminescence display concerning this invention. It is a top view for demonstrating an example of the connection wiring of the organic electroluminescent display apparatus concerning this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Anode wiring 2 Cathode wiring 3 1st common wiring 4 2nd common wiring 5 Anode connection wiring 6 Cathode connection wiring 7 Display area 8 Glass substrate 9 Positioning mark

Claims (7)

A plurality of organic EL display elements each having an anode wiring, an organic EL layer, and a cathode wiring; an anode common wiring connected via the anode wiring and the anode connection wiring in the plurality of organic EL display elements; A substrate for an organic EL display element in which a cathode wiring in an organic EL display element and a cathode common wiring connected via a cathode connection wiring are formed,
A substrate for organic EL display elements, wherein a positioning mark for dividing a plurality of organic EL display elements is formed on the common wiring for anode and / or the common wiring for cathode.   The organic EL display element substrate according to claim 1, wherein the positioning mark is formed by an opening in the wiring.   2. The organic EL display element according to claim 1, wherein a dividing line for dividing the plurality of organic EL display elements is provided on the anode common wiring and / or the cathode common wiring. substrate. Forming a plurality of organic EL display elements having an anode wiring, an organic EL layer, and a cathode wiring on a substrate;
The anode connection wiring connected to the anode wiring in the plurality of organic EL display elements, the anode common wiring connected to the anode connection wiring, and the cathode connected to the cathode wiring in the plurality of organic EL display elements Forming a connection wiring for the cathode and a common wiring for the cathode connected to the connection wiring for the cathode;
Applying a voltage for aging to the common wiring for anode and the connecting wiring for cathode; and
In order to separate the individual organic EL display elements after voltage application, a step of dividing so that all or part of the common wiring for anode and the common wiring for cathode remains in the organic EL display element is provided. Manufacturing method of organic EL display element.   5. The method for manufacturing an organic EL display element according to claim 4, wherein in the step of dividing the organic EL display element, the common wiring for anode and / or the common wiring for cathode is divided. Forming a plurality of organic EL display elements having an anode wiring, an organic EL layer, and a cathode wiring on a substrate;
The anode connection wiring connected to the anode wiring in the plurality of organic EL display elements, the anode common wiring connected to the anode connection wiring and formed with a dividing positioning mark, and the plurality of the organic EL display elements Forming a cathode connection wiring connected to the cathode wiring and a cathode common wiring connected to the cathode connection wiring;
Applying a voltage for aging to the common wiring for anode and the connecting wiring for cathode; and
And a step of dividing the organic EL display element based on at least the positioning mark after voltage application. Forming a plurality of organic EL display elements having an anode wiring, an organic EL layer, and a cathode wiring on a substrate;
An anode connection wiring connected to the anode wiring in the plurality of organic EL display elements; an anode common wiring connected to the anode connection wiring and having a first positioning mark for separation; Forming a cathode connection wiring connected to the cathode wiring in the organic EL display element, and a cathode common wiring connected to the cathode connection wiring and having a second positioning mark for separation; ,
Applying a voltage for aging to the common wiring for anode and the connecting wiring for cathode; and
And a step of dividing the organic EL display element based on the first positioning mark and the second positioning mark after voltage application.

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