JP5015237B2 - Manufacturing method of organic EL display panel - Google Patents

Description

  The present invention relates to an organic electroluminescent device and a method for manufacturing the same, and more particularly to an organic electroluminescent device that is simply patterned without deterioration of an organic functional layer and a method for manufacturing the same.

  Organic electroluminescence (hereinafter, referred to as organic EL) devices characterized by thin surface light emission, high efficiency, and the like are attracting attention. In order to produce such an organic EL device, it is necessary to sequentially laminate a first electrode, one or more organic functional layers including a light emitting layer, and a second electrode on a support substrate. At this time, since the organic functional layer is generally easily affected by heat, an organic solvent, and humidity, when the photolithography method is used for patterning the second electrode, the already formed organic functional layer is deteriorated. There is a fear.

  Therefore, when forming the second electrode on the organic functional layer, a method of forming a film only at a necessary portion by shadow mask vapor deposition is generally employed. However, it has become difficult to produce a high-definition shadow mask as the pattern of the second electrode becomes high-definition, and there is a problem that extremely high accuracy is required for alignment of the shadow mask.

  In such a situation, as shown in Japanese Patent Laid-Open No. 11-111455, a partition made of an insulator is formed on the first electrode, and an organic functional layer and a conductive thin film to be the second electrode are formed on the entire surface. A method of patterning by cutting the upper organic functional layer and the conductive thin film using a blade has been proposed.

  Also, as shown in Japanese Patent Application Laid-Open No. 8-96961, in an inorganic EL device, a photolithography method is not used by making a cut in the back electrode in contact with the reflective insulating layer and peeling off unnecessary portions of the back electrode. A method for forming an electrode pattern is disclosed.

  However, in Japanese Patent Application Laid-Open No. 11-111455, it is generally necessary to form a partition made of a resin, and thus a gas generated therefrom may adversely affect the device. Moreover, since the space between adjacent pixels cannot be made narrower than the width of the partition wall, it is difficult to realize a high-definition pattern. Furthermore, since cutting scraps are generated during pattern creation, there is a concern about short circuit.

  In Japanese Patent Application Laid-Open No. 8-96961, since adjacent pixels are separated by partially peeling back electrodes, it is necessary to make at least two cuts between adjacent pixels. is there. Therefore, it is inappropriate for forming a high-definition pattern.

  An object of the present invention is to provide a means for solving various problems mentioned above as an example.

  The organic EL device of the present invention has a plurality of organic EL cells formed on a substrate, and adjacent ones of the organic EL cells sandwich a single mechanical cutting line. And

The organic EL display panel manufacturing method of the present invention includes a step of forming a first electrode on a substrate, a step of forming an organic functional layer, a step of forming a second electrode composed of a plurality of strip-shaped electrodes, A method of manufacturing an organic EL display panel comprising: a step of forming the second electrode by mechanically cutting a conductive thin film formed on the organic functional layer, thereby strip electrodes adjacent to each other viewed contains a separation step allowed to form across the single mechanical cutting streaks in, cut in the separation step includes a Tokubi to be a rolling cutting the circular blade on the substrate To do.

  FIG. 1 is a plan view of an organic EL display panel including an organic EL device according to an embodiment of the present invention.

  2 is a cross-sectional view taken along the one-dot chain line II-II in FIG.

  3A to 3F are cross-sectional views illustrating a method of manufacturing an organic EL display panel including the organic EL device according to the embodiment of the present invention.

  FIG. 4 is a partially enlarged sectional view of the organic EL display panel.

  FIG. 5 is a partially enlarged sectional view of an organic EL display panel according to an embodiment of the present invention.

  FIG. 6 is a cross-sectional view of an organic EL display panel.

  FIG. 7 is a plan view showing an arrangement state of the blades used in the manufacturing method of the present invention.

  FIG. 8 is a block diagram of the control system of the embodiment of the present invention.

  FIG. 9 is a flowchart of the cutting step in the manufacturing method of the embodiment of the present invention.

  FIG. 10 is a cross-sectional view of an alternative example of an organic EL display panel provided with the organic EL device of the present invention.

  FIG. 11 is a cross-sectional view of an alternative example of an organic EL display panel provided with the organic EL device of the present invention.

  FIG. 12 is a cross-sectional view of an alternative example of an organic EL display panel provided with the organic EL device of the present invention.

  FIG. 13 is a plan view of an alternative example of an organic EL display panel provided with the organic EL device of the present invention.

  FIG. 14 is a plan view of an alternative example of an organic EL display panel provided with the organic EL device of the present invention.

  FIG. 15 is a plan view of an alternative example of an organic EL display panel provided with the organic EL device of the present invention.

  FIG. 16 is a plan view of an alternative example of an organic EL display panel including the organic EL device of the present invention.

  FIG. 17 is a cross-sectional view showing a manufacturing method of an alternative example of an organic EL display panel provided with the organic EL device of the present invention.

  FIG. 18 is a flowchart of the insulation / short-circuit inspection step in the manufacturing method according to the embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

  Hereinafter, an organic EL display panel including an organic EL device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 is a plan view of an organic EL display panel including an organic EL device according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken in the direction of the arrow when the panel of FIG. 1 is cut along a dashed line II-II. It is. In these drawings, 3 rows × 5 columns of light emitting cells (organic EL cells) are shown for the sake of simplicity, but the present invention is limited to such a matrix. is not. In the following description, an area where the plurality of light emitting cells are arranged is referred to as a light emitting area.

  In an organic EL display panel including an organic EL device according to an embodiment of the present invention, striped first electrodes 20 made of a conductive material are arranged on a support substrate 10 in the column direction. In the case of a bottom emission type panel, light is extracted to the outside through the substrate 10 and the first electrode 20, so that both the substrate 10 and the first electrode 20 are formed of a light-transmitting material. For example, alkali-free glass, polycarbonate, or the like is used for the substrate 10, and indium tin oxide (ITO), indium zinc oxide (IZO), or the like is used for the first electrode 20. As will be described later, a conductive thin film serving as a second electrode is formed above the substrate 10 and the first electrode 20 and then mechanically cut using a blade, so that the substrate 10 and the first electrode 20 are formed. Both of them preferably have a hardness higher than the cutting edge of the blade. Thereby, it is avoided that the board | substrate 10 and the 1st electrode 20 are damaged or deform | transformed in the case of the cutting | disconnection by the said cutter.

  In addition, the hardness of a laminated film can be measured and compared by Vickers hardness. In particular, as for the hardness of the thin film, a diamond indenter is pushed into the thin film in the same manner as the measurement of Vickers hardness, and the indentation depth and load at that time are measured to obtain the hardness of the thin film. If it is difficult to measure the hardness of the thin film itself, the hardness of the thin film may be determined by measuring the hardness of a bulk material having the same composition as the thin film.

  On the first electrode 20, at least one organic functional layer is formed. Such an organic functional layer is made of an organic compound such as a low molecule, a dendrimer, or a polymer, and may partially contain an inorganic material. The organic functional layer is a single layer structure of a light emitting layer, a two layer structure composed of a hole transport layer and a light emitting layer, a three layer structure composed of a hole transport layer, a light emitting layer and an electron transport layer, or a hole injection layer, a hole Various structures such as a five-layer structure including a transport layer, a light emitting layer, an electron transport layer, and an electron injection layer can be taken.

  In the present embodiment, these organic functional layers are collectively formed in the light emitting region, the first organic functional layer 30, and the second organic functional layer 40 that is separately formed for each light emitting cell and formed into an island shape. They are distinguished. For example, when the first electrode 20 is an anode, the first organic functional layer 30 is a hole injection layer made of copper phthalocyanine or the like and a hole transport layer made of triphenylamine derivative or the like. In addition, when it is not necessary to coat the light emitting layer separately, the light emitting layer can also be included in the first organic functional layer 30. The second organic functional layer 40 is a light emitting layer made of, for example, an aluminum chelate complex. When the first electrode 20 is an anode, an electron injection layer made of Li2O or the like and an electron transport layer made of Alq3 or the like can be included in the second organic functional layer 40 as necessary.

  On the 1st and 2nd organic functional layers 30 and 40, the striped 2nd electrode 55 which consists of an electroconductive material is arrange | positioned in the direction orthogonal to the 1st electrode 20, ie, a row direction. Here, the adjacent strip electrodes of the second electrode 55 are arranged with a single mechanical cutting mark L interposed therebetween. In the case of a top emission type panel, light is extracted to the outside through the second electrode 55, and therefore, a material such as ITO or IZO having a light transmitting property is used for the second electrode 55. Moreover, since the 2nd electrode 55 is formed by cut | disconnecting an electroconductive thin film with a blade etc. so that it may mention later, it is desirable to use a material softer than the blade edge | tip of the said blade.

  On the organic EL display panel, a lead electrode connected to the first electrode 20 and / or the second electrode 55 is further provided. The material of the extraction electrode is required to have low resistance and environmental resistance. Generally, a single layer film such as Cr, Ti, Al, Al—Nd alloy, Ag alloy, ITO, or a laminated film thereof is used. The lead electrode has a connection part electrically connected to the first electrode 20 or the second electrode 55 at one end thereof. Note that the extraction electrode may be omitted unless particularly required. In the present embodiment, an extraction electrode 70 connected to the second electrode 55 is shown as an example.

  As described above, the organic EL device of the present embodiment is configured by a matrix-like light emitting cell formed at the crossing position of the stripe-shaped first electrode 20 and the stripe-shaped second electrode 55 orthogonal to the stripe-shaped first electrode 20. The light emitting cells adjacent to each other are arranged with a single cut line interposed therebetween. Thus, since the organic EL devices of the present invention are adjacent to each other with the light emitting cells sandwiching only the cut streak, it is possible to realize a light emitting cell with high brightness and high definition. In addition, since the second electrode is not formed using a chemical process such as photolithography that deteriorates the organic functional layer, the life of the product can be extended.

In the present embodiment, the description has been made on the assumption that the first electrode and the second electrode are an anode and a cathode, respectively, but the present invention is not limited to this case, and the first electrode and the second electrode are not limited thereto. May be a cathode and an anode, respectively.
Next, a method for manufacturing an organic EL display panel including the above-described organic EL device will be described. First, as shown to FIG. 3A, the 1st electrode 20 which consists of an electroconductive material is formed on the board | substrate 10 used as the support substrate of the organic electroluminescent display panel of an Example. Specifically, a conductive material is formed on the substrate 10 by vapor deposition or sputtering, and then patterned by photolithography to form the first electrode 20.

  Here, it is desirable that the cross-sectional shape of the edge portion of the first electrode 20 is a forward tapered shape as shown in FIG. 4A, and the taper angle α is 45 degrees or less. More desirable. This is because, when the cross section of the edge portion of the first electrode 20 stands up as shown in FIG. 4B or has an inversely tapered shape, the conductivity that becomes the organic functional layer and the second electrode above the edge portion. This is because the interface between the thin film becomes steep and the conductive thin film cannot be cut reliably.

  Furthermore, it is desirable that the tapered portion in the vicinity of the edge portion of the first electrode 20 has a gentle slope without an uneven portion. This is because if the taper portion has irregularities, the interface between the organic functional layer and the conductive thin film that becomes the second electrode is undulated above, and the conductive thin film is cut as described above. This is because the conductive thin film may not be cut reliably. Therefore, it is preferable that the first electrode 20 is in an amorphous state rather than a crystalline state during etching. Thus, the tapered portion of the edge is etched almost uniformly without being dissolved for each crystal unit as in the case of crystallinity, and becomes a gentle surface.

In the case of a passive matrix drive type organic EL display panel, as shown in FIG. 1, the first electrode 20 is patterned in a stripe shape, but in the case of an active matrix drive type, it is patterned in an island shape corresponding to a pixel. In the case of an active matrix drive type organic EL display panel, it is necessary to form an active circuit (not shown). Specifically, it is necessary to form at least two thin film transistors for driving the organic EL device, that is, a switching transistor and a driving transistor.
It is more preferable that the first electrode 20 has high adhesion to the substrate 10. Specifically, it is desirable that the first electrode 20 has a level of adhesion that does not cause peeling by a cross-cut test of JIS-K5400-8.5.2. Thereby, the problem that the 1st electrode 20 peels from the board | substrate 10 is avoided. In order to manufacture a full color organic EL display panel, the substrate 10 may be provided with a color filter, a color conversion layer, and the like.

  Next, an extraction electrode for extracting the first electrode 20 and a second electrode described later is formed. FIG. 3B shows an extraction electrode 70 for extracting the second electrode to the outside. The extraction electrode 70 is formed by, for example, forming a film by a vapor deposition method or a sputtering method and then patterning the film by a photolithography method. When high definition is not required for the pattern of the extraction electrode 70, the film may be formed using mask vapor deposition. The extraction electrode 70 may be formed simultaneously with the first electrode 20 in the step of forming the first electrode 20 described above.

  Next, as shown in FIG. 3C, the first organic functional layer 30 is formed so as to cover the entire upper surface of the first electrode 20. The first organic functional layer 30 is formed by, for example, a dry process such as an evaporation method or a sputtering method, or a wet process such as spin coating, an inkjet method, or a spray method.

  Here, the first organic layer 30 is preferably formed so as to sufficiently cover the edge portion of the first electrode 20. This is because if the first organic layer 30 does not sufficiently cover the edge portion of the first electrode 20, the conductive thin film that becomes the second electrode described later is insufficiently cut, and a short-circuited portion may occur at the cut portion. Because there is. For this purpose, specifically, it is desirable to use a vapor deposition method or a coating method in which the substrate is rotated and revolved. Among these, the coating method is particularly preferable from the viewpoint of the coverage of the edge portion of the first electrode 20.

  In addition, as shown in FIG. 5, it is desirable that the film thickness H1 of the first organic functional layer 30 is larger than the film thickness H2 of the first electrode 20. As a result, the lowermost surface of the conductive thin film 50 serving as the second electrode is always formed at a position higher than the uppermost surface of the first electrode 20. Therefore, even if the interface between the conductive thin film 50 and the organic functional layer is moved up and down so as to wave in the cutting direction, the conductive thin film 50 can be reliably cut.

  Next, as shown in FIG. 3D, the second organic functional layer 40 is formed in an island shape on the first organic functional layer 30. Unlike the first organic functional layer 30, the second organic functional layer 40 is formed separately for each pixel, and thus is formed by, for example, shadow mask vapor deposition.

  Note that the first organic functional layer 30 and the second organic functional layer 40 are stacked in the order in which at least one organic functional layer is formed in at least a cut portion of the conductive thin film 50 to be the second electrode. It is also possible to replace the film or not to form either film. Further, the film formation may be performed in a plurality of steps.

  Next, as shown in FIG. 3E, when a region covering at least the light emitting region and the extraction electrode are provided, a conductive thin film 50 is formed at the connection portion by vapor deposition or sputtering.

  Finally, as shown in FIG. 3F, patterning is performed by mechanically cutting the conductive thin film 50, thereby forming the second electrode 55 as shown in FIG. When the conductive thin film 50 is cut, it is cut while pushing the cutting edge while pressing the cutting edge with the relative speed in the direction parallel to the substrate surface of the contact point between the blade edge of the blade B and the conductive thin film 50 being zero. Therefore, it is not preferable to cut the blade B by dragging the blade edge. This is because, when cutting the blade B by dragging the blade edge, excessive friction occurs between the first electrode 20 or the substrate 10 and the blade edge of the blade B, and the surface of the first electrode 20 or the substrate 10 may be damaged. Because there is. Moreover, since the adhesive force of the conductive thin film 50 to the organic functional layer is generally weak, a burr 50a as shown in FIG. 6 is likely to occur.

  A specific method of cutting while pressing the conductive thin film 50 includes, for example, a method of cutting by rolling while pressing a circular blade against the substrate. Alternatively, there is a method of cutting the conductive thin film 50 by pressing the Thomson blade against the substrate. When a Thomson blade is used, the conductive thin film 50 can be efficiently cut by forming a Thomson blade shape in advance according to the pattern of the second electrode.

  The cutting step is preferably performed in a vacuum or in a dry gas. Thereby, it becomes possible to suppress deterioration of the organic functional layer.

  When cutting using a circular blade, the number of circular blades obtained by subtracting 1 from the number of the plurality of strip electrodes constituting the second electrode 55 (that is, the number equal to the number of mechanical cutting striations) is arranged in a row once. A method of cutting the conductive thin film 50 can be considered. However, when the pattern of the striped second electrodes 55 has a narrow pitch, the rotation axes of the circular blades adjacent to each other physically interfere with each other, so that a plurality of blades B are, for example, as shown in FIG. Alternatively, every few pieces may be arranged so as to be shifted back and forth with respect to the cutting direction and cut at a time.

  Alternatively, as shown in FIG. 7B, the interval between the adjacent circular blades is n times the pitch p of the adjacent electrode strips of the second electrode 55 (n = 3 in FIG. 7B). A plurality of circular blades are arranged so as to be cut and cut from end to end of the conductive thin film 50, and then the plurality of circular blades are put together in a direction perpendicular to the cutting direction (in FIG. 7B, an arrow M The conductive thin film 50 may be cut in n times by shifting from the end to the end again by shifting the pitch p. In the example shown in FIG. 7A, nine rotary blades are required to form nine mechanical cut striations L (that is, the second electrode 55 composed of ten strip electrodes). However, since the cutting is completed by one scan, the time for the cutting step can be shortened. On the other hand, in the example shown in FIG. 7B, in order to form nine mechanical cutting striations L, it is necessary to scan in three times, but compared to the case shown in FIG. Therefore, it is possible to reduce the cost of the equipment.

  In order to completely cut the conductive thin film 50, it is necessary to cut the conductive thin film 50 while the blade edge of the blade reaches the first organic functional layer 30. In order to cut more reliably without damaging the substrate 10 and the first electrode 20 in the lower layer, it is ideal that the cutting edge is always present in the layer of the first organic functional layer 30. However, the first organic functional layer 30 is usually a thin film of about 100 nm, and in the cutting direction, as described above, the interface between the conductive thin film 50 and the first organic functional layer 30 is waved up and down. Therefore, it is difficult to always maintain the position of the blade edge in the first organic functional layer 30. Therefore, a method of cutting the blade edge so as to contact the first electrode 20 or the substrate 10 is recommended. This makes it possible to cut the conductive thin film 50 easily and reliably. At this time, if the material used for the first electrode 20 or the substrate 10 has higher hardness than the cutting edge, the first electrode 20 and the substrate 10 will not be damaged or deformed.

  The method of cutting while the blade edge is always in contact with the first electrode 20 or the substrate 10 can be performed, for example, in the control system shown in FIG. 8 according to the flowchart shown in FIG. First, after the substrate on which the conductive thin film 50 is formed is placed at a predetermined position of the cutting apparatus, the blade is moved to the initial position by the scanning drive motor 171 (step S1). At this initial position, the blade is gradually pressed against the substrate by the vertical drive motor 172 while the pressure sensor 162 monitors the pressing of the blade against the substrate (step S2). If it is determined that the pressing of the blade against the substrate has reached a predetermined pressure, the driving of the vertical drive motor 172 is stopped (step S3), and the scan driving motor 171 is driven while the predetermined pressure is maintained, so that the conductive thin film 50 is removed. Disconnect (step S4).

  Thereafter, sealing and connection of external circuits are performed by a conventional method, and further, the panel is separated as necessary.

  The above steps complete the production of an organic EL display panel including an organic EL device composed of a plurality of light emitting cells arranged in a matrix. In the method of manufacturing the organic EL display panel according to the present embodiment, the patterning of the conductive thin film serving as the second electrode is performed not by a chemical process such as lithography but by mechanical cutting using a blade. Patterning can be easily performed without deterioration. In addition, since an organic functional layer is always provided below the mechanically cut portion, the organic functional layer plays a role of a cushion at the time of cutting, and thus the substrate and the first electrode provided in the lower layer. It is possible to reliably cut the conductive thin film serving as the second electrode without damaging the film. Furthermore, since the substrate, the first electrode, and the second electrode are generally formed of an inorganic material, the adhesion is high at the interface between them, and thus it is difficult to pattern only the second electrode. Since the organic functional layer is always provided below the mechanically cut portion, it is possible to easily pattern only the second electrode. Furthermore, it is possible to prevent a short circuit between the first electrode and the second electrode by the organic functional layer provided in the mechanically cut portion.

Example 1
A passive matrix driving type organic EL display panel was prepared by the following procedure.
1) ITO is formed on a glass substrate by a sputtering method, and 256 striped first electrodes are formed at a pitch of 0.3 mm by photoetching.
2) A lead electrode made of a metal film of Ti (50 nm) / Al (200 nm) / Ti (50 nm) is formed by sputtering and photoetching.
3) A first organic functional layer of CuPC (25 nm) / TPD (50 nm) / Alq3 (600 nm) / Li2O (1 nm) is formed in a solid shape on the portion corresponding to the light emitting region by mask vapor deposition.
4) A conductive thin film made of Al (100 nm) is formed in a solid shape in the light emitting region including the connection portion of the extraction electrode by mask vapor deposition.
5) Using an OLFA rotary cutter S type having a circular blade with a diameter of 28 mm, make 63 notches with a pitch of 0.3 mm in the direction perpendicular to the striped first electrode in the Al film (conductive thin film). By such a cutting operation, the Al film is patterned into a stripe shape composed of 64 strip electrodes.
6) Further sealing is performed to complete the organic EL display panel according to Example 1 of the present invention.

(Example 2)
A passive matrix driving type organic EL display panel was prepared by the following procedure.
1) ITO is formed on a glass substrate by a sputtering method, and 256 striped first electrodes are formed at a pitch of 0.3 mm by photoetching.
2) A lead electrode made of a metal film of Ti (50 nm) / Al (200 nm) / Ti (50 nm) is formed by sputtering and photoetching.
3) A 100-nm-thick first organic functional layer made of PEDOT is formed on the portion corresponding to the light-emitting region by a coating method such as an inkjet method or a spray method.
4) For each pixel, a second organic functional layer of TPD (50 nm) / Alq3 (600 nm) / Li2O (1 nm) is formed in an island shape by mask vapor deposition.
5) A conductive thin film made of Al (100 nm) is formed in a solid shape in the light emitting region including the connection portion of the extraction electrode by mask vapor deposition.
6) Using an OLFA rotary cutter S type having a circular blade having a diameter of 28 mm, 63 cuts of 0.3 mm pitch are made in the direction perpendicular to the stripe-shaped first electrode in the Al film (conductive thin film). By such a cutting operation, the Al film is patterned into a stripe shape composed of 64 strip electrodes.
7) Further sealing is performed to complete the organic EL panel according to Example 2 of the present invention.

  The organic EL display panel described in the above embodiment forms the pattern of the second electrode by forming the conductive thin film 50 and then cutting the conductive thin film 50 using a blade. However, after the conductive thin film 50 is formed and before the cutting, a separation preventing layer 60 may be provided at the cut portion as shown in FIG.

  The peeling prevention layer 60 preferably has high adhesion to the conductive thin film 50. Specifically, the adhesion between the peeling prevention layer 60 and the conductive thin film 50 is such that the conductive thin film 50 and the underlying layer of the conductive thin film 50 (that is, the first organic functional layer 30 or the second layer in FIG. 10). It must be higher than the adhesion between the organic functional layer 40). When it is necessary to easily determine whether or not the peel prevention layer 60 satisfies the above-described adhesion, for example, the materials used for the peel prevention layer 60, the conductive thin film 50, and the first organic functional layer 30 are solid. Lamination so as to form a three-layer structure with a film, and a cross-cut test of JIS-K5400-8.5.2 may be performed. That is, as a result of this test, if the interface between the conductive thin film and the first organic functional layer is peeled off, it can be determined that the above-described adhesion is satisfied.

  Further, the peeling prevention layer 60 is preferably formed of a material that is softer than the conductive thin film 50. Thereby, it is avoided that a crack is generated in the peeling prevention layer 60 when the conductive thin film 50 is cut, and further, it is avoided that the peeling is difficult due to the provision of the peeling prevention layer 60. Moreover, it is preferable that the material used for the peeling prevention layer 60 is low outgases, such as an inorganic substance.

  In the above description, the peeling prevention layer 60 has been described on the assumption that it is formed only at the cut portion. However, the present invention is not limited to this case. For example, as shown in FIG. 11, the conductive thin film 50 is formed. You may form in the area | region substantially the same as the area | region currently done. Or as shown in FIG. 12, you may form widely so that the electroconductive thin film 50 may be covered.

  Furthermore, when forming the peeling prevention layer 60 as shown in FIGS. 11 and 12, if the peeling prevention layer 60 is formed of a conductive material such as a metal, the resistance of the second electrode can be reduced. preferable. Examples of such a metal material include low-melting point metals such as Bi, Pb, Sn, Cd, or In. Since these low-melting-point metals also have relatively soft characteristics, they are excellent in the effect of avoiding burrs. Of these, Bi, Sn, or In is particularly desirable from the viewpoint of toxicity.

(Example 3)
1) A conductive thin film to be the second electrode is formed by the same method as in the first and second embodiments.
2) A 200 nm-thickness peeling prevention layer made of In was formed on the Al film by mask vapor deposition so as to have the same pattern as the Al film. Thus, the production method according to the present invention can be realized in exactly the same manner as in Examples 1 and 2 except for the formation of the peeling prevention layer.
In the organic EL display panel according to the embodiment of the present invention described above, the organic functional layer is formed only in the light emitting region. As a result, when the second electrode 55 and the extraction electrode 70 are electrically connected, there is no organic functional layer interposed therebetween, so that a good contact state can be ensured between the two electrodes. It becomes possible. However, in the manufacturing method according to the present invention, when the first and second organic functional layers are formed as shown in FIG. 1, no organic functional layer is formed between the extraction electrodes adjacent to each other. In this case, a conductive thin film to be the second electrode is formed directly on the substrate. Therefore, when the conductive thin film is cut, the conductive thin film formed between the adjacent lead electrodes may not be completely cut.

  Therefore, in an alternative example of the organic EL panel according to the present invention, as in the organic EL display panel 120 shown in FIG. 13, the conductive thin film 50 is formed in the film formation region of the first organic functional layer 31 except for the lead electrode 70. The film is formed in a wider area than the film formation area. As a result, the organic functional layer always exists under the portion where the conductive thin film 50 to be the second electrode is cut, which causes a connection failure between the second electrode and the extraction electrode. Therefore, the second electrode can be surely cut.

  Further, like the organic EL display panel 121 shown in FIG. 14, the film formation region of the first organic functional layer 32 is further expanded as compared with FIG. 13 described above, and is formed so as to cover a part of the edge of the extraction electrode. May be. As a result, the upper surface of the first organic functional layer 32 can form a gently inclined surface in the vicinity of the edge portion of the extraction electrode 70, so that the second electrode that is likely to occur at the step portion of the edge portion of the extraction electrode 70 is formed. The disconnection problem is solved, and the second electrode and the extraction electrode can be reliably connected.

  Further, as in the organic EL display panel 122 shown in FIG. 15, the end on the lead electrode side of the conductive thin film 51 serving as the second electrode may be formed in a comb blade shape. In this case, since the interval between adjacent comb blades can be made larger than the interval between adjacent strip electrodes of the second electrode 55 in the light emitting region, a conventional film forming method such as mask vapor deposition is used. It becomes possible to form a comb blade shape easily.

  Further, as in the organic EL display panel 123 shown in FIG. 16, a conductive thin film 52 serving as the second electrode is formed only in the light emitting region, and the so-called “connection” is used to connect the second electrode and the extraction electrode later. Electrode 58 "may be formed. The connecting electrode 58 may be formed before the conductive thin film 52 to be the second electrode is formed, or may be formed after the conductive thin film 52 is cut.

  Further, as in the organic EL display panel 130 shown in FIG. 17, the insulating film 80 may be formed before the first organic functional layer 30 is formed on the cut portion of the conductive thin film. The insulating film 80 is preferably formed thicker than the first organic functional layer 30. This makes it possible to increase the distance between the first electrode 20 and the conductive thin film 50 serving as the second electrode at the cut portion as compared with FIG. 3F. It becomes possible to prevent a short circuit between them more completely. In addition, since the conductive thin film 50 used as the 2nd electrode 20 is isolate | separated by pushing out instead of cutting on this insulating film as mentioned above, a burr | flash does not arise.

  When the cutting tool used for cutting becomes worn, cutting of the conductive thin film may be partially incomplete. Also, the cutting may be incomplete due to other factors such as the presence of foreign matter.

  Therefore, after cutting the conductive thin film 50 to be the second electrode 20, an insulation / short-circuit inspection step for inspecting whether or not the adjacent strip electrodes of the second electrode are completely insulated may be added. . For example, it is possible to determine insulation or short-circuit by applying a predetermined voltage between adjacent strip electrodes and measuring a current value using a short-circuit sensor 163 of the control system as shown in FIG.

  Further, when a plurality of panels are repeatedly cut using the same blade, for example, the time for blade replacement can be notified according to the flowchart shown in FIG. That is, a short circuit is determined using the above-described short circuit sensor 163 (step S11), and the inspection results of each of the plurality of organic EL display panels cut using the same blade are accumulated in the storage medium of the control device 150. If it is stored (step S12) and the inspection result determined to be a short circuit exceeds a predetermined frequency (step S13), the information is output to a cutting device or the like to notify the time for blade replacement. (Step 14). In addition, when repeatedly cutting a plurality of panels using a plurality of blade sets, in step S12, by accumulating and storing the inspection results for each blade constituting the blade set, individual blades are stored. It becomes possible to determine the replacement time.

Claims (14)

A method of manufacturing an organic EL display panel comprising: forming a first electrode on a substrate; forming an organic functional layer; and forming a second electrode comprising a plurality of strip electrodes.
In the step of forming the second electrode, the conductive thin films formed on the organic functional layer are mechanically cut, so that adjacent strip electrodes in the plurality of strip electrodes are mechanically cut into a single piece. Including a separation step for forming a streak;
The manufacturing method characterized in that the cutting in the separation step is rolling cutting of a circular blade on the substrate. Formation step of the organic function layer, the manufacturing method according to claim 1, comprising the steps of forming at least one layer of the organic functional layer in the portion where the mechanical cutting streaks are formed.   The manufacturing method according to claim 1, further comprising a step of forming an anti-peeling layer on at least an upper layer portion of the portion where the mechanical cut streaks are formed.   The manufacturing method according to claim 3, wherein the peeling prevention layer is formed in a region substantially the same as a region where the conductive thin film to be the second electrode is formed.   The manufacturing method according to claim 3, wherein the peeling prevention layer is formed so as to cover the conductive thin film to be the second electrode.   The manufacturing method according to claim 3, wherein the peeling prevention layer is made of a metal.   6. The manufacturing method according to claim 3, wherein the peeling prevention layer is made of at least one of Bi, Pb, Sn, Cd, and In.   The manufacturing method according to claim 1, further comprising a step of forming an extraction electrode connected to the second electrode.   The manufacturing method according to claim 8, wherein the organic functional layer is formed in a region wider than a region where the conductive thin film serving as the second electrode is formed except for the region of the extraction electrode. Method.   9. The organic functional layer is formed in a region wider than a region where a conductive thin film serving as the second electrode is formed except for a region of a non-edge portion of the extraction electrode. The manufacturing method as described in.   2. The manufacturing method according to claim 1, wherein the step of forming the second electrode includes a step of forming an end portion on the lead electrode side in the conductive thin film to be the second electrode in a comb blade shape. 9. The manufacturing method according to claim 8 , wherein the step of forming the second electrode includes a step of forming a connecting electrode that connects the second electrode and the extraction electrode.   The manufacturing method according to claim 1, further comprising a step of inspecting an insulation state of the second electrode after completion of the step of forming the second electrode. For a plurality of organic EL display panels in which the second electrode is formed using the same blade, a step of accumulating and storing the results of the inspection step, and an insulation failure in the accumulated and stored inspection results Determining whether the frequency exceeds a set value;
The manufacturing method according to claim 13, further comprising a step of notifying if the frequency of insulation failure exceeds a set value as a result of the determination.

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