Production of substrate for display element and substrate for display element

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a method for manufacturing a display element substrate for manufacturing a plurality of small display element substrates by cutting out a plurality of small display element substrates from a large material substrate which is a material. The present invention particularly relates to a method for cutting out a substrate for a display element without impairing the adhesion strength between the electrode of the metal thin film and the surface of the substrate. INDUSTRIAL APPLICABILITY The present invention is useful for manufacturing a substrate for an organic electroluminescence element (hereinafter referred to as "organic EL element") and a substrate for a field emission type display element (hereinafter referred to as "FED").

【0002】

[Conventional technology]

10 to 14 are views showing a conventional method for manufacturing a substrate for an organic EL element. As shown in FIG. 10, on the insulating material substrate 52 such as large glass, a plurality of electrode portion forming regions 51 serving as substrates for organic EL elements are partitioned by a cut-out line L indicated by a alternate long and short dash line. Before forming a substrate for an organic EL element by cutting along the cutting line L, a layer structure as an organic EL element is formed in each electrode portion forming region 51, and then each electrode portion forming region 51 is formed into a material substrate. Cut out from 52.

【0003】

As shown in FIG. 11, first, in each electrode portion forming region 51, an anode 53, which is a striped electrode portion formed by sputter vapor deposition or the like, is formed by ITO (Indium-Tin Oxide). The striped anode 53 is connected to every other two common electrodes 55 for anodes formed outside the electrode portion forming region 51. That is, the striped anode 53 is divided into two comb-shaped systems, and both systems are combined in a nested manner.

【0004】

Although not shown, an organic layer including a light emitting layer made of an organic compound is formed on the anode 53. This organic layer is composed of, for example, a hole transport layer and an electron transport light emitting layer. Further, on this organic layer, a cathode having a stripe pattern substantially the same as that of the anode 53, such as Mg: Ag, Al: Li, is formed so as to be orthogonal to the anode 53.

【0005】

After the layer structure of the organic EL element is completed, before cutting out each electrode portion forming region 51 from the material substrate 52, the organic EL element formed in each electrode portion forming region 51 is electrically inspected. That is, by applying a predetermined voltage between the common electrode for the anode 55 and the common electrode for the cathode, it is inspected whether or not the anode 53 and the cathode are short-circuited. Further, by applying a predetermined voltage between the two common electrodes 55 and 55 for the anode, the insulation state between the adjacent anodes 53 and 53 is inspected. Similarly, by applying a predetermined voltage between two common electrodes for cathodes, the insulation state between adjacent cathodes is inspected.

【0006】

After the insulation inspection, a groove 57 is formed on the back surface of the material substrate 52 with a super steel bite 56 along the cutting line L shown in FIGS. 10 and 11 as shown in FIG.

【0007】

As shown in FIG. 13, the unnecessary portion of the material substrate 52 is cut off with the groove 57 as a fulcrum. By this folding, a large number of substrates 58 for organic EL elements are taken out from the common material substrate 52.

【0008】

[Problems to be Solved by the Invention]

However, when the groove 57 is formed by the super steel bite 56, the material substrate 52 is pressed by the super steel bite 56 and bends, so that tension is applied to the anode 53 and the cathode formed on the opposite surface of the groove 57. Will work.

【0009】

Further, as shown in FIG. 13, when the material substrate 52 is folded off, a compressive force acts on the bent and deformed anode 53 and the cathode, and a tension acts when the material substrate 52 is further divided.

【0010】

For this reason, the adhesion strength between the anode 53 and the cathode of the extracted organic EL element substrate 58 is reduced, and as shown in FIG. 14, minute interfacial peeling occurs. was there. In other words, the thin film of the electrode sometimes peeled off from the surface of the substrate and floated up.

【0011】

Then, a box-shaped container is sealed on the outer peripheral edge of the organic EL element substrate 58 to form the organic EL element. However, if the anode 53 or cathode formed on the outer peripheral edge of the organic EL element substrate 58 floats from the substrate as described above, when the box-shaped container is sealed at that portion, the sealed portion is sealed. Performance problems are likely to occur. For example, moisture enters from the outside to the inside through the interface peeled part, and the moisture affects the organic layer to generate dark spots that are non-light emitting parts, which causes a decrease in emission brightness and thus a life characteristic of organic EL. Become.

【0012】

The above-mentioned problems are the same in FED. For example, when the container portion (anode substrate) is sealed on the FED substrate (cathode substrate) on which FEC is created, air enters the element and the degree of vacuum deteriorates. This causes a decrease in emission efficiency and damage to the emitter cone.

【0013】

The present invention has been made to eliminate the above-mentioned drawbacks, and an object of the present invention is to manufacture a display element substrate for cutting out a relatively small display element substrate from a relatively large material substrate. In the method, the material substrate is cut without applying tension and compressive force to the electrode portion by removing a part of the electrode pattern drawn outward from the electrode portion inside the cutting line L of the substrate for the display element. The purpose is to prevent interfacial peeling of the electrode portion.

【0014】

Another object is to remove a part of the electrode pattern without damaging the material substrate by evaporating and removing the electrode portion formed in the vicinity of the common electrode with a laser.

【0015】

Another purpose is to cover the material substrate at a position other than the part to be removed before removing a part of the electrode part, so that the constituent substances of the evaporated electrode part can be removed from the other parts of the electrode part and the like. The purpose is to prevent it from being adsorbed on the surface and causing insulation failure.

【0016】

Another object is to seal the inside of the display element substrate by forming the end portions of the electrode portions on the display element substrate inward at a predetermined interval from the outer peripheral edge of the display element substrate. The purpose is to manufacture an excellent display element. Further, this is to prevent the moisture resistance of the display element itself, the improvement of the life characteristic, and the decrease of the degree of vacuum in the element.

【0017】

[Means for solving problems]

In order to achieve each of the above objects, the present invention comprises the following means. The method for manufacturing a display element substrate according to claim 1 is a method for manufacturing a display element substrate for cutting out a display element substrate (organic EL element substrate 2) from the material substrate (1). An electrode portion (anode 3 and cathode 6) is formed inside the cutting line (L) of the display element substrate set to the above, and an electrode pattern is continuously drawn out from the cutting line L to the electrode portion. To form. Next, the electrical characteristics of the electrode portion are inspected using the electrode pattern. Next, a part of the electrode pattern is removed at the cutting line L. Next, the material substrate is cut at the cutting line L, and the display element substrate is taken out.

【0018】

Further, as the method for manufacturing the substrate for the display element, as described in claim 2, a part of the electrode portion (anode 3, cathode 6) may be evaporated and removed by a laser.

【0019】

Further, as described in claim 3, the above two methods for manufacturing a substrate for a display element are described in a position other than the part to be removed before removing a part of the electrode portion (anode 3, cathode 6). The material substrate (1) may be covered.

【0020】

The display element substrate according to claim 4 is the display element substrate (2) manufactured by the method for manufacturing the display element substrate according to any one of claims 1 to 3, wherein the electrode portion (anode 3, cathode) is used. The end of 6) is characterized in that it is formed inside the display element substrate (organic EL element substrate 2) at a predetermined interval from the outer peripheral edge.

【0021】

BEST MODE FOR CARRYING OUT THE INVENTION

First, a method for manufacturing a substrate for an organic EL device having an XY matrix structure according to an embodiment of the present invention will be described with reference to FIGS. 1 to 9.

【0022】

FIG. 1 shows a large insulating material substrate 1. In this example, four organic EL element substrates 2 are cut out from the material substrate 1. As the material substrate 1, a glass or acrylic transparent resin is used.

【0023】

First, the material substrate 1 is thoroughly cleaned. On the surface of the material substrate 1, a cutting line L (indicated by a alternate long and short dash line) for partitioning the substrate 2 for an organic EL element is set, and the inside thereof is an electrode portion forming region.

【0024】

As shown in FIG. 2, ITO having a thickness of 0.1 μm is applied in a stripe shape to each electrode portion forming region to form an anode 3 as a first electrode portion. Anode 3 is striped. Each striped anode 3 extends beyond the electrode portion forming region beyond the cutting line L, and is one for two common electrodes 4 and 4 for anodes formed on both outer sides of the electrode portion forming region. It is connected every other time. That is, the striped anode 3 is divided into two comb-shaped anodes, and both systems are nested in a minute interval.

【0025】

As shown in FIG. 3, the organic layer 5 composed of the hole transport layer and the electron transport light emitting layer is sequentially laminated and formed on the anode 3. These organic layers 5 are formed by thin-film deposition in a vacuum apparatus, and a mask is used if necessary.

【0026】

As shown in FIG. 4, a striped cathode 6 which is a second electrode portion is further formed on the organic layer 5 by mask vapor deposition. The stripes of cathode 6 are orthogonal to the stripes of anode 3. Each striped cathode 6 extends beyond the electrode portion forming region beyond the cutting line L, and is one for each of the two common electrodes 7 and 7 for the cathode formed on both outer sides of the electrode portion forming region. It is connected every other time. That is, the striped cathode 6 is divided into two comb-shaped systems, and both systems are nested in a minute interval. The striped anodes 3 and cathodes 6 that are orthogonal to each other form a matrix for arbitrarily selecting the light emitting position.

【0027】

In the above steps, the main structure of the organic EL element was formed on the substrate 1, but before cutting out the organic EL element substrate 2 from the material substrate 1, the common electrode 4 for the anode and the common electrode 7 for the cathode were used. , Inspect the electrode part and organic layer 5. That is, an insulation inspection between the anode 3 and the cathode 6 facing each other with the organic layer 5 in between, an insulation inspection between the striped anode 3 and the anode 3 arranged at a minute interval, and an arrangement at a minute interval. Perform an insulation inspection between the striped cathode 6 and the cathode 6. These insulation inspections can be performed by applying an appropriate voltage to each of the common electrode 4 for the anode and the common electrode 7 for the cathode in an appropriate combination to see if a short circuit occurs. In recent years, in particular, the electrode pitch of electrodes having a matrix structure has been improved, and it has become difficult to set up a probe on a thin electrode for insulation inspection. However, since the common electrode is provided in this example, the insulation inspection can be easily performed.

【0028】

After this inspection is completed, CO is shown along the cut line L surrounding the electrode formation region in FIG.₂Irradiate with a laser or YAG laser. The stripes of the anode 3 and the cathode 6 were connected to the common electrodes 4 and 7 outside the electrode portion forming region beyond the cutting line L, but by this laser irradiation, as in the example of the anode 3 shown in FIG. It becomes discontinuous at least in the part corresponding to the cutting line L. That is, in the cutting line L, the anode 3 continuous with the common electrode 4 for the anode is divided. The cathode 6 continuous with the common electrode 7 for the cathode is also divided in the same manner.

【0029】

Next, as shown in FIG. 5, a groove 11 is formed along the cutting line L with diamond or a super steel bite 10 on the back surface of the material substrate 1 (the surface on the side where the electrode portion or the like is not formed). At the time of forming the groove, the material substrate 1 is pressed and bent by the super steel bite 10, and a tensile stress acts on the opposite side of the material substrate 1. However, since the electrodes in this portion have already been removed by the laser as described above, tension does not act on the anode 3 and the cathode 6 even if the material substrate 1 is bent by the pressing force of the super steel bite 10. ..

【0030】

After that, as shown in FIG. 6, the material substrate 1 is folded from the back surface to the front surface with each groove 5 as a fulcrum, and the unnecessary portion of the material substrate 1 is removed in a strip shape. Further, in the same manner, the material substrate 1 is folded from the back surface to the front surface with each groove 5 formed in the material substrate 1 as a fulcrum. When this material substrate is folded, since there is no metal thin film continuous with the electrode portion at the folding position, no compressive force acts on the electrode portion (including the cathode 6 in addition to the anode 3 shown in the figure).

【0031】

As a result, as shown in FIGS. 7 and 8, the substrate 2 for the organic EL element is finally obtained. According to the substrate 2 for an organic EL element, the electrode made of a metal thin film (anode 3 in the illustrated example) has strong adhesion to the substrate. Further, since no force is applied to the electrode portion (anode 3 in the illustrated example) when the material substrate is folded, the residual stress of the electrode portion around the substrate is extremely small. The same applies to the cathode 6.

【0032】

An organic EL device is manufactured using the substrate 2 for an organic EL device obtained as described above. Specifically, as shown in FIG. 9, the container portion 12 is sealed on the upper surface side of the substrate 2 for the organic EL element to form an enclosure. Here, the end of the anode 3 is a distance d from the outer peripheral edge of the organic EL element substrate 2.₁Only located inside. In addition, the thickness of the sealed portion of the container portion 12 is the distance d.₁Less than t₁It is said that. Therefore, the container portion 12 is directly fixed to the surface of the substrate 2 with an adhesive. When the substrate 2 and the container portion 12 are sealed between the thin films that are about to peel off, a problem is likely to occur in the sealing property, but such a problem does not occur in this example. In the sealing process, the inside of the outer enclosure is made to have a specific atmosphere with low humidity.

【0033】

In the above-described embodiment, before the part of the anode 3 and the cathode 6 is removed by evaporating with a laser, the portion of the material substrate 1 other than the portion to be irradiated with the laser may be covered with some cover. By covering the electrode portion other than the removed portion and the organic layer 5 in this way, it is possible to prevent contamination due to adhesion of metal that evaporates and scatters around.

【0034】

In the above-described embodiment, the substrate 2 for an organic EL device having an electrode portion having an XY matrix structure has been described, but the present invention is not limited to the electrode portion having a matrix structure. In short, when the element substrate is cut out from the material substrate, the test electrode pattern continuous with the electrode portion of the element substrate extends beyond the cutting line L to the material substrate outside the element substrate. Can be applied to.

【0035】

Further, in the above-described embodiment, the substrate for the organic EL element has been described, but the substrate can also be applied to the FED substrate. That is, before the FED substrate is cut off from the material substrate, the conductive thin film composed of Nb, Al, W, ITO, etc. is removed from the cutting line L. More specifically, in the manufacture of the FED cathode substrate, the cathode conductor and the gate electrode formed beyond the cutting line L are removed. Further, in the manufacture of the Fed anode substrate, the anode conductor formed beyond the cutting line L is removed.

【0036】

In particular, if the present invention is applied to the cathode substrate and the anode substrate of FED, it is possible to perform an insulation test on the anode conductor and the cathode conductor formed at a fine pitch. Further, since the sealing can be performed on the peripheral portions of both substrates without the metal thin film, the sealed state inside the element can be improved, the emission efficiency can be improved, and the emitter cone can be prevented from being damaged.

【0037】

[Effect of the invention]

As described above, in the method for manufacturing a display element substrate according to the present invention, when the display element substrate is cut out from the material substrate, the test electrode pattern continuous with the electrode portion of the display element substrate is displayed beyond the cutting line. When the plate is extended to the material substrate outside the element substrate, a part of this electrode pattern is removed and divided, so that tension and compressive force are applied to the electrode portion when the plate is broken by the cutting line. Can be avoided. This makes it possible to prevent interfacial peeling of the electrode portion.

【0038】

Further, if a laser is used to remove the electrode portion near the cutting line, the metal thin film constituting the electrode portion can be evaporated and removed, and only the unnecessary metal thin film can be removed without damaging the material substrate. it can.

【0039】

Further, by covering the material substrate at a position other than the part to be removed before removing a part of the electrode part, the constituent materials of the electrode part that have been evaporated and removed are adsorbed to the electrode part or the like, resulting in poor insulation or the like. It is prevented that the inconvenience of the above occurs.

【0040】

Further, the end of the electrode portion formed on the display element substrate is formed inside at a predetermined interval from the outer peripheral edge of the display element substrate to manufacture a display element in which the inside is sealed. This makes it possible to improve the moisture resistance and life characteristics of the display element itself and prevent the decrease in the degree of vacuum inside the element.

[Simple explanation of drawings]

[Figure 1]

It is a top view of the material substrate in embodiment of this invention.

[Figure 2]

It is a partially enlarged view of the electrode part formation region set on the material substrate in embodiment of this invention, and is the figure which shows the state which formed the anode.

[Fig. 3]

It is a partially enlarged view of the electrode part formation region set on the material substrate in embodiment of this invention, and is the figure which shows the state which formed the organic layer on the anode.

[Fig. 4]

It is a partially enlarged view of the electrode part formation region set on the material substrate in embodiment of this invention, and is the figure which shows the state which the cathode is formed on the organic layer.

[Fig. 5]

It is a perspective view which shows the state of the material substrate folding in embodiment of this invention.

[Fig. 6]

It is a side view which shows the state of the material substrate folding in embodiment of this invention.

[Fig. 7]

It is a side view which shows the edge part of the substrate for an organic EL element obtained in the Embodiment of this invention.

[Fig. 8]

It is a top view of the substrate for an organic EL element obtained in the Embodiment of this invention.

[Fig. 9]

It is a side view which shows the sealing process of the substrate for organic EL element and the container part obtained in embodiment of this invention.

[Fig. 10]

It is a top view of the conventional material substrate.

[Fig. 11]

It is a partially enlarged view of the electrode part formation region set in the conventional material substrate, and is the figure which shows the state which formed the anode.

[Fig. 12]

It is a perspective view which shows the state of the folding of the conventional material substrate.

[Fig. 13]

It is a side view which shows the state of the folding of the conventional material substrate.

[Fig. 14]

It is a side view which shows the edge part of the substrate for an organic EL element obtained by the conventional manufacturing method.

[Explanation of symbols]

1 ... Material substrate 2 ... Substrate for organic EL elements 3 ... Anode 4 ... Common electrode for anode 5 ... Organic layer 6 ... Cathode 7 ... Common electrode for cathode L ... cutting line