JP5043600B2 - Organic EL element panel - Google Patents

Description

  The present invention relates to an organic EL element panel.

  In recent years, organic EL element panels, which are self-luminous devices, have attracted attention as flat panel displays.

  Usually, an organic EL element has a sandwich structure in which an organic light emitting layer is sandwiched between two electrodes on a glass substrate. In order to extract light from the organic light emitting layer to the outside, one of the electrodes is transparent, and a transparent electrode such as ITO (Indium Tin Oxide) is generally used for the anode. . Furthermore, the outer peripheral surface of the organic EL element is sealed with a sealing material, and emits light when a current is passed through an external drive circuit.

  Organic EL elements that emit light based on the above principle are excellent in visibility and flexibility, and have various color development properties. Therefore, they are used in displays and display elements such as in-vehicle car components and mobile phones. Development is thriving.

  Although it is an organic EL element panel having these characteristics, the problem that the organic EL element is extremely weak against moisture is well known. As an example, moisture contained in an environmental atmosphere when sealing a glass substrate on which an organic light emitting layer is formed or moisture that permeates through a defective portion of the sealing layer enters the organic EL element. As a result, a non-light-emitting region called a dark spot is generated, and there is a problem in life that light emission cannot be maintained.

  As one measure for solving the problem relating to the lifetime of the organic EL element, a protective film for the organic EL element has been actively developed, and the protective film is formed from the outside of the organic light emitting layer to a wide range around the outside. A method of blocking moisture is used.

  Patent Document 1 discloses a method of forming a protective film having a multilayer structure by plasma CVD so as to cover an organic EL element.

  On the other hand, the organic EL element panel is required to have not only high brightness and high viewing angle but also lighter weight, thinner thickness, narrow frame, and the like. Therefore, Patent Document 2 discloses a wiring method capable of narrowing the frame of the organic EL element panel.

  By the way, in the electrode terminal portion of the organic EL element, an anisotropic conductive film (ACF) is used to bond the flexible printed circuit board (FPC), which is an external connection electrode corresponding to the plurality of electrode terminal portions, by thermocompression bonding. The method performed by is generally used.

  Usually, the electrode terminal portion is located at the end of the substrate, and the formation of a film is prevented by a mask or the like so that a protective film is not formed on the electrode terminal portion. Therefore, in the organic EL element in which the protective film is formed, the FPC is bonded via the ACF to the electrode terminal portion (exposed portion of the electrode) exposed to the outside from the final end of the protective film.

  FIG. 8 is a top view schematically showing a stage before joining external connection electrodes in a conventional organic EL element panel. FIG. 9A is a partial cross-sectional view schematically showing between the point C and the point C ′ in FIG. FIG. 9B is a partial cross-sectional view schematically showing a state in which the external connection electrode is joined between the point C and the point C ′ in FIG. 8.

  Hereinafter, the illustrated organic EL element panel will be described in accordance with a manufacturing method.

  First, the lower electrode 42 is formed on the substrate 41. An organic layer 43 is formed thereon. The organic layer 43 is composed of at least one organic layer. An upper electrode 44 is formed thereon, and a protective film 45 is further formed thereon by plasma CVD. The protective film 45 is formed on the entire surface other than the region covered with a mask so as not to be formed in a necessary length of the electrode terminal portions 46 and 47, for example, a 1.5 mm portion. Subsequently, an FPC 48 is joined to the electrode terminal portions 46 and 47 by thermocompression bonding using ACF (not shown) to produce an organic EL element panel.

JP 2002-329720 A JP 2004-355998 A

  However, the protective film formed by plasma CVD as in Patent Document 1 has a slope shape in which the film thickness distribution is generated at the edge of the mask and the film thickness gradually decreases as the protective film reaches the edge.

  Therefore, in order to achieve sufficiently long-term stabilization performance, the coverage of the uneven part of the substrate and the film thickness distribution of the mask edge sufficiently cover the element at the end while taking into account the element shape. The film thickness must be as high as possible. Therefore, the film forming distance from the element end to the electrode terminal portion has to be long.

  Furthermore, since it is necessary to mount the FPC on the electrode terminal portion where the protective film is not formed, two distances are required, that is, the generation length of the film thickness distribution and the length of the electrode terminal portion, and it is difficult to narrow the frame. There was a problem.

  Further, as in Patent Document 2, in order to achieve a narrow frame, in order to route the electrode under the protective film formed on the entire surface to the surface opposite to the substrate, etching is performed to form a connection hole, and There is a method of connecting to the electrode formed in the above. However, this method requires the etching of the connection holes and the subsequent formation of the conductors for the connection with the electrodes, firing, etc., which adds a number of processes and increases costs. It was. In addition, since the entire surface opposite to the substrate is used for wiring, there is a problem that it can be used only with a bottom emission type element.

  In addition, in order to obtain a narrow frame, when the length of the electrode terminal portion or the like is formed short and the FPC is mounted only on the electrode terminal portion using a conventional joining method, the electrode terminal portion is only a very short distance. . For this reason, there is a problem in the bonding strength that stress is applied to the end and peeling occurs when the bonding distance is short, so that all of the peeling occurs immediately.

  Accordingly, the present invention provides an organic EL element panel that can ensure the bonding strength of the external connection electrode even if the exposed electrode length is short without increasing the cost and the process, and thus can obtain a narrow frame. The purpose is to provide.

As means for solving the above problems, the present invention provides:
A first electrode formed on the substrate, an organic light emitting layer, a second electrode, and a protective film covering at least one of the electrodes so as to expose an electrode terminal portion located at an end of the substrate; Have
An inclined part is formed at the end of the protective film,
Across the top of the inclined portion of the electrode terminal, a front Symbol protective film is adhered external connection electrodes through an anisotropic conductive film, and the electrode terminal portion and the external connection electrodes are electrically connected and,
The anisotropic conductive film includes conductive particles,
The diameter of the conductive particles is larger than the thickness of the protective film .

  The organic EL element panel of the present invention has the effect of ensuring the bonding strength of the external connection electrode even if the exposed electrode length is short without increasing the cost and the process, and thus obtaining a narrow frame. is there.

  Hereinafter, embodiments of the organic EL element panel of the present invention will be described.

<Embodiment 1>
First, the organic EL element panel of Embodiment 1 will be described along with a manufacturing method.

  FIG. 1 is a partial cross-sectional view schematically showing the organic EL element panel of Embodiment 1. As shown in FIG. FIG. 2A is a partial cross-sectional view schematically showing a stage before joining the FPC in the vicinity of the electrode terminal portion. FIG. 2B is a partial cross-sectional view schematically showing a state in which the electrode terminal portion and the FPC are joined with ACF particles. In FIG. 1, ACF is omitted. 2A and 2B are schematic views that are close to the actual size ratio.

  1 and 2, 1 is a glass substrate on which a TFT circuit is formed, 2 is an anode electrode (first electrode), 3 is an organic layer, 4 is a cathode electrode (second electrode), 5 is a protective film, and 6 is a protective film. It is an inclined part of the film. 7 is an electrode terminal portion (exposed portion of the electrode), 8 is an FPC (external connection electrode), 9 is an ACF (anisotropic conductive film), 10 is a conductive particle, 11 is an element isolation film, and 12 is a planarization film. .

  First, a planarizing film 12 made of an acrylic resin is formed on a glass substrate 1 on which a TFT circuit is formed by a photolithography method, and unevenness due to the circuit is flattened.

An anode electrode 2 is formed. The anode electrode 2 may be a transparent electrode such as ITO or In ₂ O ₃ , or contains at least one kind of Au, Ag, Al, Pt, Cr, Pd, Se, Ir, copper iodide, etc. A reflective electrode made of an alloy or the like may be used.

  The organic layer 3 is formed. The organic layer 3 is composed of at least one organic layer. More specifically, for example, it is composed of an organic layer 3 such as a hole injection layer, a hole transport layer, an organic light emitting layer, an electron transport layer, and an electron injection layer. There are cases where light is emitted from only one organic layer 3, and light emission may occur at the interface between adjacent organic layers. In the present embodiment, the number of layers of the organic layer 3 can be appropriately selected in consideration of the light emitting function.

  A cathode electrode 4 is formed. The cathode electrode 4 may also be transparent or a reflective electrode.

A protective film 5 is formed. The protective film 5 only needs to be a material having electrical insulation and airtightness. For example, if the protective film 5 can suppress or prevent deterioration of the organic EL structure by forming SiO ₂ or SiN by plasma CVD. Good. The protective film 5 is preferably formed in all regions other than at least the electrode terminal portion 7 of at least one of the anode electrode 2 and the cathode electrode 4.

  When the protective film 5 is formed into a mask by plasma CVD, the thickness of the mask end portion becomes thinner toward the end, and an inclined portion 6 having a slope shape is formed. The method for forming the protective film 5 is not limited to plasma CVD, and any other method such as sputtering or vapor deposition may be used as long as the inclined portion 6 is formed by a forming method in which the film thickness decreases toward the periphery of the protective film 5. But you can. If the end of the protective film 5 is rectangular, it may be processed into a slope by etching or the like.

  The maximum thickness of the protective film 5 is preferably less than the conductive particle diameter in the ACF 9. For example, if the conductive particle diameter of ACF9 is 10 μm, the maximum thickness of the protective film 5 is preferably less than 10 μm. The conductive particles 10 of the ACF 9 are not limited to the size of the particle diameter but are crushed and deformed to electrically connect the electrode terminal portion 7 and the FPC 8 via the conductive particles 10 of the ACF.

  In addition, since the ACF bonding is adjusted so that the substrate and the heater head are substantially parallel to each other and uniformly apply pressure, when the protective film 5 is thicker than the conductive particles 10, the conductive particles 10 are not crushed. This is because they often do not conduct.

It is desirable that the length of the electrode terminal portion 7 to be exposed is a minimum necessary length. The length of the electrode terminal portion 7 to be exposed is related to the allowable current amount of the ACF 9 and the actual amount of current that flows. For example, when the width of one electrode terminal portion 7 is 0.3 mm and the length is 0.5 mm, if the allowable current amount of ACF 9 is 500 mA / mm ² , 0.3 × 0.5 × 500 mA = 75 mA. Thus, the amount of current that can flow is 75 mA.

Further, if the allowable current amount of ACF 9 is 1000 mA / mm ² , it becomes 150 mA. When the amount of drive current that actually flows is, for example, 200 mA, the allowable current amount per area becomes insufficient. In that case, for example, if the method of increasing the width of the electrode terminal portion 7 or increasing the number of lines through which a large amount of current flows is used, the amount of current that actually flows is less than the allowable amount of current per area. Therefore, there is no problem with the amount of current. Even when the width of the electrode terminal portion 7 is increased or the number of the electrode terminal portions 7 is increased, there is a margin that can be increased to the left and right of the electrode terminal portion 7 as shown in the figure. Never do. Further, if the allowable current amount of ACF 9 exceeds 1000 mA / mm ² , the necessary current amount can be sufficiently supplied without increasing the line width or increasing the number of lines.

  Therefore, the length of the electrode terminal portion 7 to be exposed can be set as appropriate based on the relationship between the allowable current amount of the ACF 9, the amount of current actually passed, and the layout of the wiring, and the length of the electrode terminal portion 7 to be exposed is zero. The length is not limited to 5 mm, and may be less than that.

  Subsequently, the ACF 9 is temporarily bonded over the electrode terminal portion 7 and the inclined portion 6 of the protective film, and then the FPC 8 is bonded by thermocompression bonding. As a result, the FPC 8 is formed over the electrode terminal portion 7 and the inclined portion 6 of the protective film, and the electrode terminal portion 7 and the FPC 8 are electrically connected.

  Since the FPC 8 is formed over the electrode terminal portion 7 and the inclined portion 6 of the protective film, even if the exposed length of the electrode terminal portion 7 is short, the bonding area of the FPC 8 can be earned, There is no peeling. That is, without increasing the cost and the process, the bonding strength with the external connection electrode can be ensured even if the exposed electrode length is short, and thus a narrow frame can be obtained.

  Moreover, since the conductive particle diameter of the ACF is thicker than the maximum thickness of the protective film 5 as described above, the electrode terminal portion 7 is deformed by crushing and deforming the conductive particles 10 even if the sectional shape around the protective film 5 is inclined. However, the FPC 8 can be electrically connected through the conductive particles 10.

  In addition, since the protective film 5 is thinned over the electrode terminal portion 7 and the final end (outer peripheral end) of the inclined portion 6 of the protective film has almost no step with the electrode terminal portion 7, the FPC 8 is joined through the ACF 9. Then, even if the exposed area is small, it can be joined to almost the entire region of the electrode terminal portion 7.

  Note that a circularly polarizing plate (for example, a polarizing plate formed by a combination of a linear polarizing plate and a retardation plate such as a λ / 4 plate) can be directly attached on the protective film 5. Further, after the protective film 5 is formed, sealing can be performed with glass, a glass substrate may be used, or a glass cap having a step formed by processing the glass substrate may be used. It can also be sealed with a resin or the like.

<Embodiment 2>
Next, the organic EL element panel of Embodiment 2 will be described along with a manufacturing method. The process up to the formation of the protective film 5 is the same and will not be described.

  After the protective film 5 is formed, an extraction electrode is formed across the electrode terminal portion 7 and the inclined portion 6 of the protective film (not shown). For example, when the left and right layout of the electrode terminal portion 7 has no margin, the allowable electrode amount of the ACF 9 is small, and when the length and thickness of the electrode terminal portion 7 and the number of currents that can be flowed are not sufficient, the extraction electrode is removed. It is good to form.

The extraction electrode may be a transparent electrode such as ITO or In ₂ O ₃ , or contains at least one of Au, Ag, Al, Pt, Cr, Pd, Se, Ir, copper iodide, etc. An alloy or the like may be used.

  As a method for forming the extraction electrode, any method may be used as long as a wiring pattern can be formed in one step, such as sputtering, vapor deposition, plating, and the like, as long as it can be electrically connected to an external substrate such as FPC8.

The length of the extraction electrode is related to the allowable current amount of the ACF 9 and the actual amount of current to be passed, as with the electrode terminal portion 7. For example, when the width of one extraction electrode is 0.3 mm and the length is 1.5 mm, if the allowable current amount of ACF9 is 500 mA / mm ² , 0.3 × 1.5 × 500 mA = 225 mA, The amount of current that can be passed is 225 mA. When the amount of drive current that actually flows is, for example, 200 mA, the drive current amount is smaller than the allowable current amount per area. Therefore, it is sufficient that the length of the extraction electrode is 1.5 mm. It is only necessary to form a length that can reduce the amount of current that actually flows than the allowable current amount per area, and it is necessary to add the length on the slope of the protective film to the length on the electrode terminal. It is only necessary to form a take-out electrode having such a length that the amount of driving current can be reduced.

  Subsequently, the FPC 8 is joined to the extraction electrode by thermocompression bonding via the ACF 9. When the protective film 5 is formed as a mask, the film thickness at the edge of the mask becomes thinner toward the edge, resulting in a slope shape. The take-out electrode formed thereon also has a sloped shape following it. Since the conductive particle diameter of the ACF is thicker than the thickness of the protective film 5, the conductive particle 10 can electrically take out the electrode and the FPC 8 at any position by crushing and deforming the conductive particle 10 even if the cross-sectional shape is inclined. Can be connected.

  In the first and second embodiments, after the FPC 8 is bonded over the electrode terminal portion 7 and the inclined portion 6 of the protective film, or over the electrode terminal portion 7 and the inclined portion 6 of the protective film. After forming the take-out electrode and joining the FPC 8, it is preferable to apply a protective resin. The protective resin can prevent moisture from entering the joint from the outside and suppress the occurrence of ion migration. Further, since the joining force is not so strong with ACF 9 alone, it is preferable to apply it from the viewpoint of reinforcing the joining force.

<Example 1>
An embodiment to which the present invention can be applied will be described with reference to FIGS.

  Below, the organic EL element panel of a present Example is described along the preparation methods.

[Planarization film forming process]
A planarizing film 12 made of an acrylic resin was formed on the glass substrate 1 on which the TFT circuit was formed by a photolithography method, and unevenness due to the circuit was flattened.

[Anode electrode formation process]
A Cr target was DC sputtered on the glass substrate on which the planarizing film 12 was formed, and a Cr film having a thickness of 100 nm was formed as the anode electrode 2. At this time, a pixel electrode of 20 μm × 100 μm was formed using a film formation mask. The film formation was performed using Ar gas under a pressure of 0.2 Pa and an input power condition of 300 W.

[Element isolation film forming step]
In order to separate each pixel, an element isolation film 11 made of polyimide resin was formed by a photolithography method.

[Pretreatment process]
It moved to the organic electroluminescent vapor deposition apparatus, evacuated, and 50-W RF electric power was supplied to the ring-shaped electrode provided near the board | substrate in the pre-processing chamber, and the oxygen plasma cleaning process was performed. The oxygen pressure was 0.6 Pa and the treatment time was 40 seconds.

[Hole transport layer forming step]
The substrate is moved from the pretreatment chamber to the film formation chamber, and after the film formation chamber is evacuated to 1 × 10 ⁻⁴ Pa, αNPD having hole transportability is formed at a film formation rate of 0.2 to 0 by resistance heating vapor deposition. The film was formed under the condition of 3 nm / sec to form a 35 nm-thick hole transport layer. Note that the hole transport layer, the organic light emitting layer, and the electron injection layer were deposited on predetermined portions by using the same deposition mask. The predetermined portion is a portion where the pixel electrode Cr is exposed on the substrate.

[Organic light emitting layer forming step]
On the hole transport layer, Alq ₃ which is an alkylate complex was formed by resistance heating vapor deposition under the same film formation conditions as the hole transport layer to form an organic light emitting layer having a film thickness of 15 nm.

[Electron injection layer forming step]
A film is formed on the organic light-emitting layer by adjusting each deposition rate so that Alq ₃ and cesium carbonate (Cs ₂ CO ₃ ) are mixed at a ratio of 9: 1 by resistance heating co-evaporation. An electron injection layer having a thickness of 35 nm was formed. Specifically, the material set in each evaporation boat is evaporated by resistance heating method, the organic layer is ~ 5 A / S, and the co-deposition layer is also adjusted to the respective boat current value. Film formation was performed at a speed.

[Cathode electrode (transparent conductive film) formation process]
The substrate was transferred to another film formation chamber, and the cathode electrode 4 made of ITO was formed on the electron injection layer by using a ITO magnet target by DC magnetron sputtering.

[Protective film formation process]
The substrate was moved to another film formation chamber, and mask film formation was performed so that no film was formed on the electrode terminal portion 7. After evacuating the vacuum vessel to 0.2 Pa or less, silane gas 30 sccm and ammonia 300 sccm were flowed to control the pressure in the reaction space to 100 Pa. Thereafter, high-frequency power of 100 mW / cm ² is supplied to the high-frequency electrode, and a silicon nitride film is deposited and formed to a thickness of 3 μm by plasma CVD without covering the organic EL element and part of the electrode and without heating the substrate. The film 5 and the inclined portion 6 of the protective film were formed. At this time, the protective film 5 and the inclined portion 6 of the protective film were formed so that the exposed length of the electrode terminal portion 7 was 0.5 mm.

[Mounting process]
FPC mounting necessary for connecting a drive circuit for driving the organic EL element panel was performed. First, ACF 9 was temporarily pressure-bonded over the electrode terminal portion 7 on the substrate 1 and the inclined portion 6 of the protective film. Next, the FPC 8 is aligned with the electrode terminal portion 7. Thereafter, joining of the FPC 8 was completed across the electrode terminal portion 7 and the inclined portion 6 of the protective film by thermocompression bonding with a heater head.

[Protective resin application process]
A protective resin was applied to the portion where the FPC 8 was joined across the electrode terminal portion 7 and the inclined portion 6 of the protective film. As the protective resin, an acrylic ultraviolet curable resin was used, and after application, the resin was cured by irradiation with ultraviolet rays.

  The organic EL element panel manufactured by the above processes can ensure the bonding strength of the FPC 8 and the bonding strength of the FPC 8 even if the exposed electrode length is short, without increasing the cost and the process. I was able to get it.

<Example 2>
An embodiment to which the present invention can be applied will be described with reference to FIGS.

  FIG. 3 is a top view schematically showing a stage before joining the external connection electrodes in the organic EL element panel of the present embodiment. FIG. 4A is a partial cross-sectional view schematically showing between point A and point A ′ in FIG. 3. FIG. 4B is a partial cross-sectional view schematically showing a state in which the FPC that is the external connection electrode is joined between the point A and the point A ′ in FIG. 3.

  As shown in the drawing, the organic EL element panel of this example is a passive matrix panel. 3 and 4, 13 is a glass substrate, 14 is a lower electrode (first electrode), 15 is an organic layer, 16 is an upper electrode (second electrode), 17 is an electrode terminal portion, 18 is a protective film, 19 is An inclined portion of the protective film, 20 is an FPC.

  Below, the organic EL element panel of a present Example is described along the preparation methods.

[Lower electrode formation process]
An Al target was DC sputtered on the glass substrate 13 on which the planarizing film was formed, and an Al film was formed as the lower electrode 14 to a thickness of 100 nm. Using Ar gas, the pressure was 0.2 Pa and the input power was 300 W.

[Hole transport layer forming step] [Organic light emitting layer forming step] [Electron injection layer forming step]
Since it is the same formation method as Example 1, it abbreviate | omits.

[Upper electrode formation process]
The substrate was transferred to another film formation chamber, and a film was formed on the electron injection layer by a DC magnetron sputtering method using an ITO target so as to have a film thickness of 130 nm, thereby forming an upper electrode 16 made of ITO.

[Protective film formation process]
The substrate was moved to another film formation chamber, and mask film formation was performed so that no film was formed on the electrode terminal portion 17. After evacuating the vacuum vessel to 0.2 Pa or less, silane gas 30 sccm and ammonia 300 sccm were flowed to control the pressure in the reaction space to 100 Pa. Thereafter, high-frequency power of 100 mW / cm ² is supplied to the high-frequency electrode, and a silicon nitride film is deposited and formed to a thickness of 4 μm by plasma CVD without covering the organic EL element and part of the electrode and heating the substrate. And the inclined part 19 of the protective film was formed. At this time, the protective film 18 and the inclined portion 19 of the protective film were formed so that the exposed length of the electrode terminal portion 17 was 0.5 mm.

[Mounting process]
FPC mounting necessary for connecting a drive circuit for driving the organic EL element panel was performed. First, ACF (not shown) was temporarily pressure-bonded over the electrode terminal portion 17 on the substrate 13 and the inclined portion 19 of the protective film. Next, the FPC 20 was aligned with the electrode terminal portion 17. Thereafter, the FPC 20 was joined across the electrode terminal portion 17 and the inclined portion 19 of the protective film by thermocompression bonding with a heater head. This was performed on four sides to complete the FPC joining.

[Protective resin application process]
A protective resin was applied to the portion where the FPC 20 was joined across the electrode terminal portion 17 and the inclined portion 19 of the protective film. As the protective resin, an acrylic ultraviolet curable resin was used, and after application, the resin was cured by irradiation with ultraviolet rays.

  The organic EL element panel manufactured by the above processes can ensure the bonding strength and the bonding strength of the FPC 20 even if the exposed electrode length is short, without increasing the cost and the process, and thus the narrow frame can be secured. I was able to get it.

  Further, since it is a passive matrix type, the four sides can be narrowed, and the overall substrate size can be reduced as compared with the conventional panel.

<Example 3>
An embodiment to which the present invention can be applied will be described with reference to FIG.

  FIG. 5A is a partial cross-sectional view schematically showing a state in which an extraction electrode is formed across the electrode terminal portion and the inclined portion of the protective film. FIG. 5B is a partial cross-sectional view schematically showing a state in which an FPC is joined to the extraction electrode.

  In FIG. 5, 21 is a glass substrate on which a TFT circuit is formed, 22 is an anode electrode, 23 is an organic layer, 24 is a cathode electrode, 25 is a protective film, 26 is an inclined portion of the protective film, 27 is an electrode terminal portion, 28 Is an extraction electrode, 29 is an FPC, 30 is an element isolation film, and 31 is a planarization film.

  Below, the organic EL element panel of a present Example is described along the preparation methods. Since most of the manufacturing methods are the same as those in the first embodiment, only different portions will be described in detail.

  A planarization film 31 was formed on the TFT substrate, and an anode electrode was formed. Subsequently, an element isolation film 30 was formed. After moving to an organic EL vapor deposition apparatus and performing pretreatment, hole transport layer formation, organic light emitting layer formation, and electron injection layer formation were performed.

[Cathode electrode (transparent conductive film) formation process]
The substrate was transferred to another deposition chamber, and a cathode electrode 24 made of ITO was formed on the electron injection layer by using a ITO magnet target by DC magnetron sputtering.

[Protective film formation process]
The substrate was moved to another film formation chamber, and mask film formation was performed so that no film was formed on the electrode terminal portion 27. After evacuating the vacuum vessel to 0.2 Pa or less, silane gas 30 sccm and ammonia 300 sccm were flowed to control the pressure in the reaction space to 100 Pa. Thereafter, high-frequency power of 100 mW / cm ² is supplied to the high-frequency electrode, and a silicon nitride film is deposited to a thickness of 3 μm by plasma CVD without covering the organic EL element and part of the electrode and without heating the substrate, and the protective film 25 And the inclined part 26 of the protective film was formed. At this time, the protective film 25 and the inclined portion 26 of the protective film were formed so that the exposed length of the electrode terminal portion 27 was 0.3 mm.

[Extraction electrode formation process]
The substrate was transferred to another deposition chamber, a Cr target was DC sputtered, and a Cr film having a thickness of 100 nm was formed as the extraction electrode 28. At this time, the thickness was set to 300 μm × 1.5 mm using a film formation mask. The extraction electrode 28 is formed over the electrode terminal portion 27 and the inclined portion 26 of the protective film using a mask when the protective film 25 is formed. Since the width and length of the extraction electrode 28 are not required to be precise, they can be sufficiently formed only by mask film formation. This panel requires a large amount of drive current, and additional electrodes cannot be formed on the left and right sides of the panel layout or cannot be made thick. Therefore, the extraction electrode 28 is disposed on the electrode terminal portion 27 and the inclined portion 26 of the protective film. Formed. In this embodiment, the extraction electrodes 28 are formed on all the electrode terminal portions 27 and the inclined portions 26 of the protective film, but they may be formed only where there is a large amount of drive current.

[Mounting process]
FPC mounting necessary for connecting a drive circuit for driving the organic EL element panel was performed. First, temporary crimping of ACF (not shown) was performed on the extraction electrode 28. Next, the FPC 29 was taken out and aligned with the electrode 28. Thereafter, joining of the extraction electrode 28 and the FPC 29 was completed by thermocompression bonding.

[Protective resin application process]
A protective resin was applied to the portion where the extraction electrode 28 and the FPC 29 were joined. As the protective resin, an acrylic ultraviolet curable resin was used, and after application, the resin was cured by irradiation with ultraviolet rays.

  The organic EL element panel manufactured by the above processes can ensure the bonding strength because the FPC 29 has a sufficient bonding area even if the exposed electrode length is short, without increasing the cost and the process, and thus a narrow frame. Could get.

  In addition, due to the layout of the wiring and the amount of drive current, the amount of current was insufficient with only the electrode terminal portion 27. However, by forming the extraction electrode 28, the amount of current can be secured even in a narrow frame without changing the frame size. did it.

<Example 4>
An embodiment to which the present invention can be applied will be described with reference to FIGS.

  FIG. 6 is a top view schematically showing a stage before joining the external connection electrodes in the organic EL element panel of the present embodiment. FIG. 7A is a partial cross-sectional view schematically showing between point B and point B ′ in FIG. 6. FIG. 7B is a partial cross-sectional view schematically showing a state in which the FPC that is the external connection electrode is joined between the point B and the point B ′ in FIG. 6.

  As shown in the drawing, the organic EL element panel of this example is a passive matrix panel. 6 and 7, 32 is a glass substrate, 33 is a lower electrode (first electrode), 34 is an organic layer, 35 is an upper electrode (second electrode), 36 is an electrode terminal portion, 37 is a protective film, 38 is An inclined portion of the protective film, 39 is an extraction electrode, and 40 is an FPC.

  Below, the organic EL element panel of a present Example is described along the preparation methods.

[Lower electrode formation process]
An Al target was DC sputtered on the glass substrate 32 on which the planarizing film was formed, and an Al film was formed as a lower electrode 33 to a thickness of 100 nm. Using Ar gas, the pressure was 0.2 Pa and the input power was 300 W.

[Hole transport layer forming step] [Organic light emitting layer forming step] [Electron injection layer forming step]
Since it is the same formation method as Example 1, it abbreviate | omits.

[Upper electrode formation process]
The substrate was transferred to another film formation chamber, and a film was formed on the electron injection layer to have a film thickness of 130 nm by DC magnetron sputtering using an ITO target to form an upper electrode 35 made of ITO.

[Protective film formation process]
The substrate was moved to another film formation chamber, and mask film formation was performed so that no film was formed on the electrode terminal portion 36. After evacuating the vacuum vessel to 0.2 Pa or less, silane gas 30 sccm and ammonia 300 sccm were flowed to control the pressure in the reaction space to 100 Pa. Thereafter, high-frequency power of 100 mW / cm ² is supplied to the high-frequency electrode, and a silicon nitride film is deposited to a thickness of 4 μm by plasma CVD without covering the organic EL element and part of the electrode and without heating the substrate. 37 and the inclined portion 38 of the protective film were formed. At this time, the protective film 37 and the inclined portion 38 of the protective film were formed so that the exposed length of the electrode terminal portion 36 was 0.4 mm.

[Extraction electrode formation process]
The substrate was transferred to another film formation chamber, and Al was DC sputtered to form an Al film with a thickness of 120 nm as the extraction electrode 39. At this time, the size was set to 200 μm × 1.2 mm using a film formation mask. The extraction electrode 39 is formed over the electrode terminal portion 36 and the inclined portion 38 of the protective film using a mask when the protective film 37 is formed. Since the width and length of the extraction electrode 39 are not required to be precise, they can be sufficiently formed only by mask film formation. In this panel, the allowable current amount of ACF is small, and additional electrodes cannot be formed on the left and right in the panel layout, or the thickness cannot be increased. Formed.

[Mounting process]
FPC mounting necessary for connecting a drive circuit for driving the organic EL element panel was performed. First, temporary crimping of ACF (not shown) was performed on the extraction electrode 39. Next, the FPC 40 was taken out and aligned with the electrode 39. Thereafter, joining of the extraction electrode 39 and the FPC 40 was completed by thermocompression bonding.

[Protective resin application process]
A protective resin was applied to the portion where the extraction electrode 39 and the FPC 40 were joined. As the protective resin, an acrylic ultraviolet curable resin was used, and after application, the resin was cured by irradiation with ultraviolet rays.

  The organic EL element panel manufactured by the above processes can ensure the bonding strength because the bonding strength area of the FPC 40 is sufficient even if the exposed electrode length is short, without increasing the cost and the process. I was able to get a picture frame.

  Further, since it is a passive matrix type, the four sides can be narrowed, and the overall substrate size can be reduced as compared with the conventional panel.

  Furthermore, from the wiring layout and the allowable current amount, the current amount was insufficient with only the electrode terminal portion 36, but by forming the extraction electrode 39, the current amount could be secured even in a narrow frame without changing the frame size. .

  As mentioned above, although the top emission type organic EL element panel was demonstrated in this invention, it is applicable not only to it but a bottom emission type organic EL element panel. In addition, the present invention is applied to a passive type, but can also be applied to an active organic EL element panel.

  In the present invention, one FPC is connected to one side, but a plurality of FPCs may be connected to one side.

It is a fragmentary sectional view which shows typically the organic EL element panel of Embodiment 1 and Example 1 of this invention. (A) is a fragmentary sectional view which shows typically the stage before joining an external connection electrode straddling on the exposed part of an electrode, and the inclined part of a protective film. (B) is a partial cross-sectional view schematically showing a state in which the external connection electrode is joined over the exposed portion of the electrode and the inclined portion of the protective film. It is a top view which shows typically the stage before joining the external connection electrode in Example 2 of this invention. FIG. 4A is a partial cross-sectional view schematically showing between a point A and a point A ′ in FIG. 3. FIG. 4B is a partial cross-sectional view schematically showing a state where an external connection electrode is joined between a point A and a point A ′ in FIG. 3. (A) is a fragmentary sectional view which shows typically the state where the taking-out electrode was formed straddling on the exposed part of an electrode, and the inclined part of a protective film. (B) is a partial cross-sectional view schematically showing a state in which an external connection electrode is bonded onto the extraction electrode. It is a top view which shows typically the stage before joining the external connection electrode in Example 4 of this invention. FIG. 7A is a partial cross-sectional view schematically showing between a point B and a point B ′ in FIG. 6. FIG. 7B is a partial cross-sectional view schematically showing a state in which an external connection electrode is joined between a point B and a point B ′ in FIG. 6. In the conventional organic EL element panel, it is a top view which shows typically the stage before joining an external connection electrode. FIG. 9A is a partial cross-sectional view schematically showing between a point C and a point C ′ in FIG. 8. FIG. 9B is a partial cross-sectional view schematically showing a state in which the external connection electrode is joined between the point C and the point C ′ in FIG. 8.

Explanation of symbols

1, 13, 21, 32 Substrate 2, 22 Anode electrode (first electrode)
3, 15, 24, 34 Organic layer 4, 24 Cathode electrode (second electrode)
5, 18, 25, 37 Protective film 6, 19, 26, 38 Protective film inclined part 7, 17, 27, 36 Electrode terminal part (exposed part of electrode)
8, 20, 29, 40 FPC (External connection electrode)
9 ACF
10 Conductive particles 14, 33 Lower electrode (first electrode)
16, 35 Upper electrode (second electrode)
28, 39 Extraction electrode

Claims (2)

A first electrode formed on the substrate, an organic light emitting layer, a second electrode, and a protective film covering at least one of the electrodes so as to expose an electrode terminal portion located at an end of the substrate; Have
An inclined part is formed at the end of the protective film,
Across the top of the inclined portion of the electrode terminal, a front Symbol protective film is adhered external connection electrodes through an anisotropic conductive film, and the electrode terminal portion and the external connection electrodes are electrically connected and,
The anisotropic conductive film includes conductive particles,
The diameter of the said electroconductive particle is larger than the thickness of the said protective film, The organic EL element panel characterized by the above-mentioned . 2. The organic EL element panel according to claim 1, wherein an extraction electrode is formed between the electrode terminal portion and the external connection electrode so as to straddle the inclined portion of the protective film.

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