JP6612406B2 - Light emitting device - Google Patents

Description

  The present invention relates to a light emitting device.

  In recent years, organic EL (Organic Electroluminescence) elements have attracted attention as new light emitting elements. Organic EL elements are used as displays and lighting devices.

  Patent Document 1 describes that an anode and a cathode of an organic EL element are protruded from an organic EL layer, and an FPC (flexible printed circuit board) is attached to the protruded portion.

  In Patent Document 2, a part of the substrate of the organic EL element is protruded, and a conductor connected to the anode and a conductor connected to the cathode are provided on the protruded part, thereby connecting the protruded part. It is described that it is used as a part.

JP 2007-66709 A JP 2004-55535 A

  In the case where the organic EL element is formed over a flexible substrate, the light emitting device such as a display or a lighting device can be flexible. On the other hand, in order to make it easy to attach the light emitting device, it is preferable to give flexibility to the external connection portion of the light emitting device. A general method for giving flexibility to the external connection portion is a method of attaching an FPC (flexible printed circuit board) to the external connection terminal of the light emitting device. However, in this method, since the FPC is attached to the light emitting device, the number of manufacturing steps of the light emitting device increases.

  As an example of the problem to be solved by the present invention, it is possible to give flexibility to the external connection portion of the light emitting device and to suppress an increase in the number of manufacturing steps of the light emitting device.

The first invention is a flexible substrate having a main body region and a protruding region protruding in a planar direction from the main body region,
An organic EL element formed in the main body region;
A first wiring formed in the protruding region and partially insulated;
It is a light-emitting device provided with.

The second invention includes a step of forming an organic EL element on the pair of first flexible substrates included in the second flexible substrate;
Removing the first flexible substrate from the second flexible substrate;
With
The first flexible substrate includes a main body region and a protruding region protruding in a planar direction from the main body region,
Of the pair of first flexible substrates, the main body region of one of the first flexible substrates is adjacent to the protruding region of the other first flexible substrate. It is a manufacturing method of a light-emitting device.

It is a top view which shows the structure of the light-emitting device which concerns on embodiment. It is a figure for demonstrating the manufacturing method of a light-emitting device. 1 is a diagram illustrating a configuration of a light emitting device according to Example 1. FIG. It is a figure which shows the usage method of the light-emitting device shown in FIG. 6 is a plan view of a light emitting device according to Example 2. FIG. It is the figure which removed the 2nd electrode, the contact bonding layer, and the sealing layer from FIG. It is AA sectional drawing of FIG. It is BB sectional drawing of FIG. 6 is a plan view showing a configuration of a light emitting device according to Example 3. FIG. It is a top view for demonstrating the manufacturing method of the light-emitting device shown in FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  FIG. 1 is a plan view showing a configuration of a light emitting device 10 according to the embodiment. The light emitting device 10 according to the present embodiment includes a flexible substrate 100, an organic EL element 200, and lead wires 112 and 114 (first wires). The flexible substrate 100 has flexibility. The flexible substrate 100 has a main body region 102 and a protruding region 104. The protruding region 104 protrudes from the main body region 102 in the planar direction. Here, projecting from the main body region 102 in the planar direction means projecting from the main body region 102 when the flexible substrate 100 is viewed from above. The organic EL element 200 is formed in the main body region 102 of the flexible substrate 100. The lead wires 112 and 114 are formed in the protruding region 104 of the flexible substrate 100. Hereinafter, the light emitting device 10 will be described in detail.

  The flexible substrate 100 is, for example, a resin substrate, but may be a thin glass substrate. A part of the edge of the protruding region 104 forms the same line as the edge of the main body region 102.

  Specifically, the planar shape of the main body region 102 of the flexible substrate 100 is, for example, a polygon such as a quadrangle, a pentagon, or a hexagon. This polygon may be a regular polygon or may not be a regular polygon. In the example shown in the figure, the main body region 102 is rectangular. The main body region 102 may be rectangular or square. The protruding region 104 extends from the top of the main body region 102, for example, one of the vertices. In the example shown in the figure, the protruding region 104 has a shape in which a part of the main body region 102 is protruded along one side of the main body region 102. In the direction in which the protruding region 104 protrudes (the x direction in the figure), the length of the protruding region 104 is equal to or less than the width of the main body region 102. Further, it is preferable that the length of the protruding region 104 is ½ or more of the width of the main body region 102.

  The organic EL element 200 is formed on one surface of the main body region 102 and has a configuration in which an organic layer is provided between the first electrode and the second electrode. One of the first electrode and the second electrode is a transparent electrode, and the other is a metal electrode. The lead wiring 112 is electrically connected to the first electrode, and the lead wiring 114 is electrically connected to the second electrode.

  The lead wires 112 and 114 are formed on the same surface as the organic EL element 200 in the protruding region 104. The lead wires 112 and 114 may be formed of a single conductive layer, or may have a structure in which a plurality of conductive layers are stacked. In any case, it is preferable that the lead wires 112 and 114 have at least one metal layer (for example, an Al layer or a Cu layer).

  A part of the lead wires 112 and 114 is insulated. Thereby, it can suppress that the lead-out wiring 112,114 contacts with another member accidentally, and is conducted. In the example shown in the drawing, the insulated portions of the lead wires 112 and 114 are covered with the first insulating member 120. The first insulating member 120 is, for example, a resin layer such as a resist, but may be formed of other insulating materials. The first insulating member 120 covers most of the lead wires 112 and 114. And the part which is not covered with the 1st insulating member 120 among the extraction wirings 112 and 114 becomes the terminal part 110. The terminal part 110 is a terminal for connecting the organic EL element 200 to the outside. In the example shown in this drawing, the terminal portion 110 is provided at the tip of the protruding region 104.

  FIG. 2 is a diagram for explaining a method of manufacturing the light emitting device 10. First, a second flexible substrate (flexible substrate 101) is prepared. The flexible substrate 101 includes at least a pair of flexible substrates 100 (first flexible substrate). Then, an organic EL element is formed on each of the flexible substrates 100. Next, the flexible substrate 100 is taken out from the flexible substrate 101. As described above, the flexible substrate 100 has the main body region 102 and the protruding region 104. Of the pair of flexible substrates 100, the main body region 102 of one flexible substrate 100 and the protruding portion 104 of the other flexible substrate 100 are adjacent to each other. Details will be described below.

  First, the flexible substrate 101 is prepared. Since the flexible substrate 101 is larger than the flexible substrate 100, the plurality of light emitting devices 10 are cut out from the flexible substrate 101.

  In the example shown in FIG. 1, the main body region 102 of the flexible substrate 100 is rectangular. The protruding region 104 extends along one side of the main body region 102. Therefore, when two flexible substrates 100 are arranged and one flexible substrate 100 is rotated 180 ° with respect to the other flexible substrate 100, the two flexible substrates 100 are combined. The shape is almost rectangular. Therefore, when the plurality of flexible substrates 100 are cut out from the flexible substrate 101, the portions of the flexible substrate 101 that are not used are reduced.

  In order to cut out in this way, as described above, the length of the protruding region 104 is equal to or less than the width of the main body region 102 in the direction in which the protruding region 104 extends, that is, in the longitudinal direction of the protruding portion 104. Yes.

  Next, the organic EL element 200 is formed in each of the regions to be the main body region 102 in the flexible substrate 101. In addition, the lead wirings 112 and 114 and the first insulating member 120 are formed in each of the regions to be the protruding regions 104 in the flexible substrate 101. The lead wires 112 and 114 are preferably formed in the same process as one of the components of the organic EL element 200. The first insulating member 120 is also preferably formed in the same process as the other component of the organic EL element 200.

  Thereafter, the flexible substrate 101 is divided into a plurality of flexible substrates 100. In this way, the light emitting device 10 is formed.

  As described above, in this embodiment, a part of the flexible substrate 100 is the protruding region 104, and the lead-out wirings 112 and 114 are formed in the protruding region 104. That is, the protruding region 104 has a function similar to that of the FPC. For this reason, it is not necessary to attach FPC to the light-emitting device 10. Further, since the protruding region 104 is a part of the flexible substrate 100, the lead wirings 112 and 114 can be formed simultaneously with the organic EL element 200. Therefore, the number of manufacturing steps of the light emitting device 10 can be reduced as compared with the case where an FPC is externally attached to the light emitting device 10.

  Further, there is no need to provide an attachment portion for attaching the FPC to the light emitting device 10. Therefore, the width of the region (edge) in the main body region 102 where the organic EL element 200 is not formed can be reduced.

Example 1
FIG. 3 is a diagram illustrating a configuration of the light emitting device 10 according to the first embodiment. The light emitting device 10 according to this example has the same configuration as the light emitting device 10 according to the embodiment except for the following points.

  First, at least the end side of the protruding region 104 is divided into a first protruding region 104a and a second protruding region 104b. In other words, the protruding region 104 has a first protruding region 104a and a second protruding region 104b on the end side. At least the end portion of the lead wiring 112 is located in the first projecting region 104a, and at least the end portion of the lead wiring 114 is located in the second projecting region 104b. A first terminal 110a is formed at the tip of the first protruding region 104a, and a second terminal 110b is formed at the end of the second protruding region 104b. The first terminal 110 a is formed using a portion of the lead wiring 112 that is not covered with the first insulating member 120, and the second terminal 110 b is covered with the first insulating member 120 of the lead wiring 114. It is formed using no part. The first terminal 110a is located, for example, at the end of the first projecting area 104a, and the second terminal 110b is located, for example, at the end of the second projecting area 104b.

  FIG. 4 is a diagram illustrating a method of using the light emitting device 10 illustrated in FIG. As described in the embodiment, the organic EL element 200 has a configuration in which an organic layer is provided between the first electrode and the second electrode. The lead wiring 112 is connected to the first electrode, and the lead wiring 114 is connected to the second electrode. Therefore, when a plurality of light emitting devices 10 are arranged and the first terminal 110a of the first protruding region 104a is connected to the second terminal 110b of the second protruding region 104b of the adjacent light emitting device 10, the plurality of light emitting devices 10 are connected in series. can do.

  As described above, according to this embodiment, the number of manufacturing steps of the light emitting device 10 can be reduced as compared with the case where an FPC is externally attached to the light emitting device 10. Further, since the projecting region 104 is divided into the first projecting region 104 a and the second projecting region 104 b, the first terminal 110 a of the first projecting region 104 a is used as the second terminal 110 b of the second projecting region 104 b of the adjacent light emitting device 10. A plurality of light emitting devices 10 can be connected in series. Therefore, the light emitting device 10 can be easily installed.

(Example 2)
FIG. 5 is a plan view of the light emitting device 10 according to the second embodiment. FIG. 6 is a view in which the second electrode 240, the adhesive layer 260, and the sealing layer 270 are removed from FIG. 7 is a cross-sectional view taken along the line AA in FIG. 5, and FIG. 8 is a cross-sectional view taken along the line BB in FIG.

  In the example shown in this figure, the flexible substrate 100 is formed of resin. Therefore, a barrier film 210 is formed on the surface of the flexible substrate 100 where the organic EL element 200 is formed. The barrier film 210 is provided to prevent moisture from permeating from the flexible substrate 100 to the organic EL element 200. The barrier film 210 is at least one inorganic film, for example, a SiON film. The barrier film 210 may have a configuration in which a plurality of layers are stacked. The barrier film 210 may have a configuration in which an inorganic film / organic film / inorganic film is stacked. The barrier film 210 is formed in both the main body region 102 and the protruding region 104.

  Note that when the flexible substrate 100 is formed of glass, the barrier film 210 is unnecessary.

  A first electrode 220, an organic layer 230, and a second electrode 240 are stacked on a portion of the barrier film 210 located in the main body region 102.

  The first electrode 220 is a transparent electrode formed of an inorganic material such as ITO (Indium Thin Oxide) or IZO (indium zinc oxide) or a conductive polymer such as a polythiophene derivative. The first electrode 220 may be a metal thin film that is thin enough to transmit light. For example, the first electrode 220 is formed on the entire surface of the region to be the organic EL element 200.

  A wiring 222 (second wiring) is formed on the first electrode 220. The wiring 222 is formed of, for example, a material (for example, metal) having a resistance lower than that of the first electrode 220. The wiring 222 is provided to reduce the apparent resistance of the first electrode 220. The wiring 222 may have a single-layer structure or a structure in which a plurality of layers are stacked. The wiring 222 has a configuration in which, for example, a Mo layer, an Al alloy layer, and a Mo layer are stacked in this order. In the example shown in this figure, a plurality of wirings 222 are provided in parallel to each other. The ends of the plurality of wirings 222 are connected to each other and then connected to the lead-out wiring 112. In the example shown in this figure, the lead-out wiring 112 and the wiring 222 are integrally formed.

  A wiring 242 (second wiring) is formed on a region of the barrier film 210 where the first electrode 220 is not formed. The wiring 242 is provided to connect the lead wiring 114 to the second electrode 240. At least a part of the wiring 242 is formed along the edge of the main body region 102. In the example shown in the figure, the wiring 242 is formed along three sides of the rectangular main body region 102 excluding the side from which the protruding region 104 protrudes. The wiring 242 is formed integrally with the lead wiring 114. Further, since the wiring 242 and the lead-out wiring 114 are formed in the same process as the wiring 222, they have the same layer structure as the wiring 222.

  The wirings 222 and 242 are covered with an insulating layer 250 (second insulating member). The insulating layer 250 is a photosensitive resin such as a polyimide resin, and is formed in a desired pattern by exposure and development. As the insulating layer 250, for example, a positive photosensitive resin is used. The insulating layer 250 may be a resin other than a polyimide resin, for example, an epoxy resin or an acrylic resin. The first insulating member 120 is formed in the same process as the insulating layer 250. For this reason, the first insulating member 120 is formed of the same material as the insulating layer 250. In the example shown in this drawing, the first insulating member 120 is formed integrally with the insulating layer 250.

  The insulating layer 250 has a plurality of stripe-shaped first openings 252. An organic layer 230 is formed on a region of the first electrode 220 located at the first opening 252. The organic layer 230 is formed by stacking, for example, a hole transport layer, a light emitting layer, and an electron transport layer. The hole transport layer is in contact with the first electrode 220, and the electron transport layer is in contact with the second electrode 240.

  A second opening 254 is formed in the insulating layer 250. The second opening 254 overlaps part of the wiring 242. In other words, a portion of the wiring 242 that overlaps with the second opening 254 is exposed from the insulating layer 250. In the example shown in this drawing, the second openings 254 are provided on each of two sides facing each other in the main body region 102 of the flexible substrate 100.

  A second electrode 240 is formed on the organic layer 230 and the insulating layer 250. The second electrode 240 is formed of, for example, a metal layer formed of a metal material such as Ag or Al, or an oxidized conductive material such as IZO. A part of the second electrode 240 overlaps the second opening 254. In other words, the second electrode 240 is connected to the wiring 242 in the second opening 254.

  In this way, the organic layer 230 is sandwiched between the first electrode 220 and the second electrode 240. A hole injection layer may be formed between the first electrode 220 and the hole transport layer, and an electron injection layer may be formed between the second electrode 240 and the electron transport layer. . Also, not all of the above layers are necessary. For example, when recombination of holes and electrons occurs in the electron transport layer, the light-emitting layer is unnecessary because the electron transport layer also functions as the light-emitting layer. Further, at least one of the first electrode 220, the hole injection layer, the hole transport layer, the electron transport layer, the electron injection layer, and the second electrode 240 may be formed using a coating method. Examples of the coating method used here include spray coating, dispenser coating, inkjet, and printing. Further, an electron injection layer made of an inorganic material such as LiF may be provided between the organic layer 230 and the second electrode 240.

  A sealing layer 270 is provided on the second electrode 240 via an adhesive layer 260. The sealing layer 270 is provided to prevent moisture from entering the organic layer 230. The sealing layer 270 is a metal foil, for example, an Al foil. Note that as the sealing layer 270, a resin substrate provided with a barrier film may be used.

  Next, a method for manufacturing the light emitting device 10 according to this example will be described. First, a flexible substrate 101 (see FIG. 2) is formed on a support substrate (for example, a glass substrate). The film thickness of the flexible substrate 101 is, for example, about 10 μm or more and about 50 μm or less. The flexible substrate 101 is formed using, for example, a coating method. Next, a barrier film 210 is formed on the flexible substrate 101. The barrier film 210 is formed by, for example, a sputtering method, but may be formed by using a CVD method or an ALD method. Note that when the support substrate is not used, the thickness of the flexible substrate 101 may be about 50 μm or more and about 300 μm or less.

  Next, the first electrode 220 is formed on the barrier film 210. The first electrode 220 is formed using, for example, a sputtering method. Thereafter, unnecessary portions of the first electrode 220 are removed by etching using the resist pattern as a mask. As a result, the first electrode 220 is formed in the main body region 102.

  Next, conductive films to be the wirings 222 and 242 and the lead wirings 112 and 114 are formed on the barrier film 210 and the first electrode 220. This conductive film is formed using, for example, a sputtering method. Next, unnecessary portions of the film are removed by etching using the resist pattern as a mask. Thereby, the wirings 222 and 242 and the lead-out wirings 112 and 114 are formed. The wires 222 and 242 and the lead wires 112 and 114 may be formed by sputtering using a mask.

  Next, the insulating layer 250 is formed on the barrier film 210, the first electrode 220, the wirings 222 and 242, and the lead wirings 112 and 114. At this time, the first opening 252 and the second opening 254 are also formed. The insulating layer 250 is formed, for example, by forming a photosensitive resin layer, and exposing and developing the resin layer. However, the insulating layer 250 may be formed using a screen printing method or an inkjet method.

  Next, the organic layer 230 is formed in the first opening 252 of the insulating layer 250. Next, the second electrode 240 is formed on the organic layer 230 by using, for example, a vacuum deposition method or a sputtering method. Next, the sealing layer 270 is attached on the insulating layer 250 using the adhesive layer 260.

  Thereafter, the flexible substrate 101 is divided using a laser or a cutter, and a plurality of light emitting devices 10 are cut out. At this time, the support substrate may also be divided. In this case, the support substrate is detached from the flexible substrate 101 after the division.

  The protruding area 104 of the flexible substrate 100 may be divided into a first protruding area 104a and a second protruding area 104b as in the first embodiment.

  Also according to the present embodiment, the number of manufacturing steps of the light emitting device 10 can be reduced as compared with the case where an FPC is externally attached to the light emitting device 10. Further, the lead wiring 112 is formed integrally with the wiring 222, and the lead wiring 114 is formed integrally with the wiring 242. Therefore, the light emitting device 10 can be easily manufactured. Furthermore, since the first insulating member 120 is formed integrally with the insulating layer 250, the light emitting device 10 can be manufactured more easily.

  Note that a region where the insulating layer 250 is not provided may be formed at the edge of the main body region 102, and the sealing layer 270 may be fixed to the main body region 102 using this region. In this case, the sealing performance of the organic EL element 200 is improved.

  In addition, since it is not necessary to attach the FPC to the light emitting device 10, it is not necessary to provide a terminal for external connection in the main body region 102. For this reason, the entire surface of the main body region 102 can be covered with the sealing layer 270. Thereby, the main body region 102 can be reinforced by the sealing layer 270. Thereby, it can suppress that the curvature of the main body area | region 102 becomes small too much, and the organic EL element 200 breaks.

  In this embodiment, the first insulating member 120 may have a multilayer structure including the same layer as the insulating layer 250. In this case, the strength of the protruding region 104 can be increased by increasing the thickness of the first insulating member 120.

Example 3
FIG. 9 is a plan view illustrating the configuration of the light emitting device 10 according to the third embodiment. The light emitting device 10 according to the present example has the same configuration as the light emitting device 10 according to the embodiment or any one of Examples 1 and 2 except for the position of the protruding region 104.

  In the present embodiment, the protruding region 104 extends from the central portion of one side of the main body region 102 in a direction (x direction in the drawing) orthogonal to the one side.

  Also in this embodiment, the number of manufacturing steps of the light emitting device 10 can be reduced as compared with the case where an FPC is externally attached to the light emitting device 10. Further, by arranging as shown in FIG. 10, the light emitting device 10 can be efficiently cut out from the flexible substrate 101. Specifically, the light emitting devices 10 are arranged in two rows in the x direction in the figure. The light emitting devices 10 belonging to the second row are directed in a direction in which the light emitting devices 10 belonging to the second row are rotated by 180 °. And the protrusion area | region 104 which belongs to the 2nd row | line | column is arrange | positioned between the main body area | regions 102 which belong to a 1st row | line.

  As mentioned above, although embodiment and the Example were described with reference to drawings, these are illustrations of this invention and can also employ | adopt various structures other than the above.

10 Light Emitting Device 100 Flexible Substrate (First Flexible Substrate)
101 flexible substrate (second flexible substrate)
102 Main body region 104 Protruding region 104a First protruding region 104b Second protruding region 110 Terminal portion 112 Lead wiring (first wiring)
114 Lead wiring (first wiring)
120 First insulating member 200 Organic EL element 222 Wiring 242 Wiring 250 Insulating layer (second insulating member)

Claims (7)

A flexible substrate;
An organic EL element that is located on the flexible substrate and has a first electrode, an organic layer, and a second electrode in that order from the flexible substrate side;
Terminals located on the flexible substrate ;
Wiring connecting the second electrode and the terminal;
An insulating member covering at least a part of the wiring;
With
The flexible substrate is
A main body region having a first side where the organic EL element is located;
A protruding region that is continuous with the first side of the main body region and protrudes from the first side of the main body region, and in which the terminal is located;
Have
The insulating member covers at least a part of the wiring in the protruding region;
A light-emitting device in which at least a part of the protruding region overlaps the main body region when viewed from the side where one surface of the main body region is located . The light-emitting device according to claim 1.
The light emitting device, wherein a width of a portion connected to the first side in the protruding region is narrower than a width of the first side. The light-emitting device according to claim 1 or 2,
The light emitting device, wherein the protruding region has a portion bent so that at least a part of the protruding region overlaps the main body region. In the light-emitting device as described in any one of Claims 1-3,
A first wiring formed in the protruding region;
A first insulating member covering the first wiring;
A second wiring formed in the main body region;
A second insulating member covering the second wiring;
A light emitting device comprising: The light-emitting device according to claim 4.
The first wiring is integrally formed with the second wiring,
The first insulating member is integrally formed with the second insulating member,
The second wiring is connected to either the first electrode or the second electrode,
The first wiring is a light emitting device electrically connected to the one. The light emitting device according to claim 5.
The light emitting device, wherein the second wiring is connected to the first electrode.   In the light-emitting device as described in any one of Claims 1-6,
  At least an end of the protruding region opposite to the main body region is divided into a first protruding region and a second protruding region,
  The first protruding region has a first terminal connected to the first electrode;
  The light emitting device, wherein the second projecting region has the terminal connected to the second electrode.

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