JP2012204250A - Organic el element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To mitigate stress exerted by an upper electrode due to division of the upper electrode into a plurality of regions by a partition wall, and also adequately prevent see-through phenomenon in the partition wall part in an organic EL element including a light-emitting pixel obtained by holding an organic film composed of an organic material between the upper electrode and a lower electrode in which the upper electrode is divided by the partition wall.SOLUTION: A partition wall 80 for dividing an organic film 30 and an upper electrode 40 into a plurality of regions 51 and 52 is disposed on a lower electrode 20 in a region of a light emitting pixel 50. A metal auxiliary electrode 90, which is a shading part and an auxiliary electrode of the lower electrode 20, is disposed between the partition wall 80 and the lower electrode 20. End portions of the metal auxiliary electrode 90 extending to a laminate part of the upper electrode 40 and the organic film 30 which are located on both sides of the partition wall 80 enter a portion between the organic film 30 and the lower electrode 20, thereby allowing for the presence of overlapped regions S1 overlapped with the upper electrode 40 with the organic film 30 interposed therebetween.

Description

  The present invention relates to an organic EL (electroluminescence) element in which an organic film made of an organic material is sandwiched between upper and lower electrodes, and particularly relates to an organic EL element excellent in light emission stability in which display failure due to luminance unevenness is suppressed.

  Since the organic EL element is self-luminous, it has excellent visibility and can be driven at a low voltage of several volts to several tens of volts, so that the weight including the driving circuit can be reduced. Therefore, it can be expected to be used as a thin film display, lighting, and backlight.

  In general, an organic EL element is composed of a laminate in which a lower electrode made of a transparent material, an organic film made of an organic material, and an upper electrode made of a material that does not transmit light are sequentially laminated on one surface of a transparent substrate. A light emitting pixel that emits light from the organic film by applying a voltage between the lower electrode and the upper electrode is provided, and light emitted from the organic film is extracted to the other side of the transparent substrate through the transparent substrate.

  On the other hand, an organic EL element described in Patent Document 1 has been proposed as an example in which a light emitting pixel is divided into a plurality of regions by partition walls. In this case, a light emitting pixel is divided into a plurality of small pixels by a partition, and a part of the partition for forming a small pixel is notched, so that when a short circuit occurs in the small pixel, an electrode is formed at the notched portion. This prevents melting and affecting the entire pixel.

JP 2001-319778 A

  The present inventor has made a trial examination based on a conventional general organic EL element. FIG. 9 is a schematic plan view of an organic EL element as the first prototype of the present inventor, and FIG. 10 is a schematic plan view showing a planar shape of each component in FIG. ) Shows the lower electrode 20, (b) shows the insulating film 60, (c) shows the organic film 30, and (d) shows the upper electrode 40.

  Here, for convenience of identification, in FIG. 9, dot hatching is applied to the insulating film 60 in FIG. 9, in the insulating film 60 in FIG. 10B, in the organic film 30 in FIG. 10C, and in FIG. Each upper electrode 40 is hatched. 10C, the end of the upper electrode 40 is indicated by a one-dot chain line, and the end of the insulating film 60 is indicated by a broken line. In FIG. 10D, the end of the organic film 30 is indicated by a one-dot chain line. The end is indicated by a broken line.

  As shown in FIGS. 9 and 10, the lower electrode 20 made of a transparent material such as ITO, the organic film 30 made of an organic material, and light such as metal are not allowed to pass through on one surface 11 of the transparent substrate 10 such as glass. A light emitting pixel 50 made of a laminate in which upper electrodes 40 made of a material are sequentially laminated is provided.

  Further, on the one surface 11 of the transparent substrate 10, outside the light emitting pixel 50, is a region where the stacked body constituting the light emitting pixel 50 is continuously expanded, and between the lower electrode 20 and the organic film 30. There is a non-light emitting region 50a in which the electrically insulating insulating film 60 is interposed. The light emitting pixel 50 is defined as a region inside the opening of the insulating film 60 as an outline of the opening. That is, the outline of the opening of the insulating film 60 corresponds to the outline of the light emitting pixel 50.

  9 and 10, the planar shape of the lower electrode 20 has an arrow shape, and the opening of the insulating film 60 has an arrow shape corresponding to the lower electrode 20 and is slightly smaller than the lower electrode 20. I am doing. And the inner edge part of the opening part of the insulating film 60 covers the outer edge part of the lower electrode 20, and the covering area | region of the lower electrode 20 by this insulating film 60 is made into the non-light-emission area | region 50a. Thereby, the light emitting pixel 50 has an arrow shape.

  Further, as shown in FIGS. 9 and 10A, the peripheral portion of the one surface 11 of the transparent substrate 10 is a drawing region R to be connected to an external circuit or the like. Are provided with extraction electrodes 21 and 22 made of the same transparent material as that of the lower electrode 20.

  The extraction electrodes 21 and 22 are formed by patterning simultaneously with the lower electrode 20, and the extraction electrode 21 for the lower electrode is formed integrally with the lower electrode 20, and the extraction electrode 22 for the upper electrode. Is in direct contact with the upper electrode 40 on the upper side to conduct.

  Also, as shown in FIGS. 10C and 10D, the organic film 30 on the lower electrode 20 and the upper electrode 40 on the organic film 30 are abbreviated except for the extraction region R on one surface 11 of the transparent substrate 10. It is formed on the entire surface.

  Here, in the lead-out region R, the end of the insulating film 60 is most widened. The end of the upper electrode 40 is located inside the end of the insulating film 60, and the organic is located inside the end of the upper electrode 40. The end of the membrane 30 is located.

  That is, the end of the organic film 30 is covered with the upper electrode 40, and the end of the upper electrode 30 is covered with the end of the insulating film 60. Thereby, the connection of the upper electrode 40 to the lead electrode 22 and the insulation and protection by the insulating film 60 are appropriately performed.

  In such a light emitting pixel 50, the organic film 30 emits light by applying a voltage between the lower electrode 20 and the upper electrode 40 via an external circuit connected to each of the extraction electrodes 21 and 22. On the other hand, in the non-light emitting region 50a, the insulating film 60 is interposed between the lower electrode 20 and the organic film 30, so that the organic film 30 does not emit light due to the voltage application.

  The light emitted from the organic film 30 is taken out through the transparent substrate 10 to the other surface side opposite to the one surface 11 of the transparent substrate 10, and a user located on the other surface side of the transparent substrate 10 visually recognizes the light. It is.

  When the first prototype is examined, the upper electrode 40 of the light emitting pixel 50 and the upper electrode 40 in a region other than the light emitting pixel 50 are continuously formed as in the first prototype. In this case, the heat generated by the light emitting pixel 50 is transmitted through the upper electrode 40 so that the entire upper electrode 40 has heat.

  According to the study of the present inventor, in the segment panel or the like, when the light emitting pixel 50 becomes a large area, the influence of the thermal stress of the upper electrode 40 as a whole increases, and between the upper electrode 40 and the organic film 30. It was found that peeling of the film occurred and luminance unevenness occurred in the light emitting pixel 50.

  Therefore, as a second prototype, the present inventor divides the upper electrode 40 into a plurality of regions by the partition wall 80 and relaxes the stress caused by the upper electrode 40 as shown in FIG. Tried to suppress. 11A and 11B are diagrams showing the configuration of the organic EL element as the second prototype, wherein FIG. 11A is a schematic plan view, and FIG. 11B is a schematic cross section taken along the dashed line AA in FIG. FIG.

  The second prototype shown in FIG. 11 is different from the first prototype shown in FIG. 9 in that a partition wall 80 is further added. In FIG. 11, point hatching is not applied to a portion of the insulating film 60 that overlaps with the partition wall 80.

  As shown in FIG. 11, the partition wall 80 is provided so as to cross the light emitting pixel 50 and completely divides the light emitting pixel 50 into a plurality of regions (here, two regions) 51 and 52.

  Specifically, the partition wall 80 is made of an electrically insulating photo-curing resin or the like, and extends on the lower electrode 20 in the region of the light emitting pixel 50 to divide the organic film 30 and the upper electrode 40 into a plurality. It is divided into areas 51 and 52. Here, the upper electrodes 40 of the plurality of regions 51 and 52 located with the partition wall 80 in between are both connected to the lead electrode 22 for the upper electrode and emit light simultaneously.

  The partition wall 80 extends to the non-light emitting region 50a, and is formed on the insulating film 60 on the lower electrode 20 in the non-light emitting region 50a. Further, in the region where the lower electrode 20 outside the non-light emitting region 50 a does not exist, the insulating film 60 is formed in direct contact with the one surface 11 of the transparent substrate 10, but the partition wall 80 is formed on the insulating film 60. Yes.

  Further, the planar shape of the lower electrode 20, the insulating film 60, and the extraction electrodes 21 and 22 of the second prototype is the same as that of the first prototype shown in FIG. The electrode 40 has a shape further divided by a partition wall 80 in the shape of FIG.

  The thermal stress increases as the area of the upper electrode 40 increases. However, if the upper electrode 40 of the light emitting pixel 50 is divided by the partition wall 80 as in the second prototype, the thermal stress is reduced, The peeling of the film between the electrode 40 and the organic film 30 can be suppressed, and the luminance unevenness of the light emitting pixel 50 can be reduced.

  In addition, although the thing of the said patent document 1 has divided the light emission pixel into the some small pixel by the partition, when the short circuit occurred in the small pixel by notching a part of a partition, it was notched The electrode is fused at the portion, and the purpose is different from that of the partition wall 80 of the second prototype. In addition, since the upper electrode is connected at the notch, stress concentrates at the notch and peeling of the film occurs between the upper electrode and the organic film, so it is difficult to suppress luminance unevenness. is there.

  Further, as a result of studying the second prototype, the present inventor has found that a medium-visible phenomenon occurs in the partition wall 80 and its vicinity. Next, the inside-visible phenomenon will be described.

  As shown in FIG. 11B, when the organic EL element is not emitting light, external light from the other surface 12 side of the transparent substrate 10 is incident on the partition wall 80 or the gap between the partition wall 80 and the upper electrode 40. In this case, depending on the incident angle, the external light cannot be reflected by the upper electrode 40 and the external light is transmitted.

  Then, it may happen that the back surface material 110 such as a case located behind the organic EL element is visible. This is the phenomenon of internal appearance. If this phenomenon of inside appearance occurs, it may cause misidentification of the user, which is not preferable.

  The present invention has been made in view of the above problems, and aims to alleviate the stress caused by the upper electrode by dividing the upper electrode into a plurality of regions by partition walls and to appropriately prevent the above-described phenomenon of appearance. And

  In order to achieve the above object, according to the first aspect of the present invention, the lower electrode (20) made of a transparent material, the organic film (30) made of an organic material, light, and the like are formed on one surface (11) of the transparent substrate (10). The upper electrode (40) made of a material that does not pass through is formed of a laminate in which the organic film (30) is formed by applying a voltage between the lower electrode (20) and the upper electrode (40). In the organic EL device, which includes a light emitting pixel (50) that emits light, and extracts light emitted from the organic film (30) through the transparent substrate (10) to the other surface (12) side of the transparent substrate (10). It has the following characteristics.

That is, in the first aspect of the present invention, in the region of the light emitting pixel (50), the organic film (30) and the upper electrode (40) are divided to extend over the lower electrode (20) to divide the plurality of regions (51, 52). ) Are provided on the lower electrode (20).
A plurality of regions (51, 52) located across the partition wall (80) emit light simultaneously,
Between the partition wall (80) and the lower electrode (20) therebelow is provided a metal auxiliary electrode (90) that is a light shielding part that blocks light and is configured as an auxiliary electrode of the lower electrode (20). ,
The metal auxiliary electrode (90) extends from the partition wall (80) to the laminated portion of the organic film (30) with the upper electrode (40) located on both sides of the partition wall (80) across the partition wall (80).
The end of the metal auxiliary electrode (90) located in the laminated portion enters between the organic film (30) and the lower electrode (20), so that the upper electrode (40) and the upper electrode (40) are interposed through the organic film (30). An overlapping region (S1) that overlaps exists.

  According to this, when a user or the like looks at the organic EL element from the other surface (12) side of the transparent substrate (10) on the light extraction side, the portion located between the divided regions of the light emitting pixels (50), that is, Since the gap between the partition wall (80) and the partition wall (80) and the organic film (30) and the upper electrode (40) is shielded by the metal auxiliary electrode (90), the back substance (110) can be seen. Disappear.

  Therefore, by dividing the upper electrode (40) into the plurality of regions (51, 52) by the partition wall (80), the stress caused by the upper electrode (40) can be relieved and the above-described phenomenon of appearance can be prevented appropriately. it can. Further, according to the present invention, since the metal auxiliary electrode (90) functions as an auxiliary electrode of the lower electrode (20), the wiring resistance of the lower electrode (20) can be apparently reduced.

  According to a second aspect of the present invention, in the organic EL element according to the first aspect, the upper electrode (40) and the metal auxiliary electrode (90) are made of the same material.

  According to this, since the reflectance can be made substantially the same between the upper electrode (40) and the metal auxiliary electrode (90), the external surface from the other surface (12) side of the transparent substrate (10) which is the light extraction side. The reflected light of the light can be made substantially the same level in the upper electrode (40) and the metal auxiliary electrode (90), and the appearance is improved.

Moreover, in invention of Claim 3, in the organic electroluminescent element of Claim 1 or 2, it is a light emitting pixel on the outer side of a light emitting pixel (50) on one surface (11) of a transparent substrate (10). (50) is a region in which the laminated body continuously expands, and the electric insulating insulating film (60) is interposed between the lower electrode (20) and the organic film (30). There is a non-light emitting region (50a) in which light emission of the organic film (30) due to voltage application does not occur,
The light emitting pixel (50) is defined as an inner portion of the opening as a region in the opening of the insulating film (60).
In the non-light emitting region (50a), a low resistance for reducing the resistance of the lower electrode (20) made of a lower resistance material than the lower electrode (20) between the lower electrode (20) and the insulating film (60). An auxiliary electrode (100) is provided.

  According to this, it is apparent that the wiring resistance of the lower electrode (20) can be further reduced, which is preferable.

  In addition, the code | symbol in the bracket | parenthesis of each means described in the claim and this column is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a schematic perspective view which shows the attachment state to the vehicle-mounted meter of the organic EL element which concerns on 1st Embodiment of this invention. It is a figure which shows the structure of the organic EL element which concerns on 1st Embodiment, (a) is a schematic plan view, (b) is a BB schematic sectional drawing in (a). It is CC schematic sectional drawing in Fig.2 (a). It is a figure which shows the structure of the organic EL element which concerns on 2nd Embodiment of this invention, (a) is a schematic plan view, (b) is DD schematic sectional drawing in (a). It is a schematic plan view of the organic EL element which concerns on 3rd Embodiment of this invention. It is EE schematic sectional drawing in FIG. It is a schematic plan view of the organic EL element which concerns on 4th Embodiment of this invention. It is FF schematic sectional drawing in FIG. It is a schematic plan view of the organic EL element as a 1st trial product of this inventor. FIG. 10 is a schematic plan view showing individual components in FIG. 9, wherein (a) shows a lower electrode, (b) shows an insulating film, (c) shows an organic film, and (d) shows an upper electrode. (A) is a schematic plan view of the organic EL element as a 2nd trial product of this inventor, (b) is AA schematic sectional drawing in (a).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other are given the same reference numerals in the drawings in order to simplify the description.

(First embodiment)
FIG. 1 is a schematic perspective view showing a state where the organic EL element 1 according to the first embodiment of the present invention is attached to a vehicle-mounted meter. 2A and 2B are diagrams showing a configuration of the organic EL element 1 according to the present embodiment, in which FIG. 2A is a schematic plan view, and FIG. 2B is a schematic cross section taken along a dashed line BB in FIG. FIG. FIG. 3 is a schematic cross-sectional view along the alternate long and short dash line CC in FIG.

  For convenience of identification, in FIG. 1, the insulating film 60 is dot-hatched. As will be described later, the insulating film 60 is also present immediately below the partition wall 80, but in FIG. 1, the portion of the insulating film 60 that overlaps the partition wall 80 is not subjected to point hatching.

  The organic EL element 1 shown in FIGS. 1 to 3 substantially includes a metal auxiliary electrode 90 (shown by a broken line in FIG. 2A) in contrast to the second prototype shown in FIG. Although it is an added structure and there are some overlaps, it will be described mainly focusing on supplementary items and differences from the second prototype.

  As shown in FIG. 1, the organic EL element 1 of the present embodiment is attached to the front face of a dial face 110 of the meter as a display of an in-vehicle meter. The front side of the dial plate 110 is a user side such as a driver, that is, a side on which a so-called viewer is located. Therefore, the dial 110 is a back material 110 located behind the organic EL element 1.

  As shown in FIG. 2, the organic EL element 1 of the present embodiment is also made of a transparent electrode 10, a lower electrode 20 made of a transparent material, an organic film 30 made of an organic material, and a material that does not transmit light. A light emitting pixel 50 that is formed of a laminated body in which the upper electrode 40 is sequentially laminated and emits the organic film 30 by applying a voltage between the lower electrode 20 and the upper electrode 40 is provided.

  Also in the present embodiment, on the one surface 11 of the transparent substrate 10, on the outer side of the light emitting pixel 50, there is a region in which the laminated body constituting the light emitting pixel 50 continuously extends, and the lower electrode 20 and the organic Between the film 30, there is a non-light emitting region 50 a where the organic film 30 does not emit light due to voltage application due to the presence of the electrically insulating insulating film 60.

  The light emitting pixel 50 is defined as a region inside the opening of the insulating film 60 as an inner portion of the opening, and the inner portion of the opening of the insulating film 60 corresponds to the outer portion of the light emitting pixel 50. It has become.

  Furthermore, also in the present embodiment, in the region of the light emitting pixel 50, the electrically insulating partition wall 80 that extends onto the lower electrode 20 and divides the organic film 30 and the upper electrode 40 to partition the region into a plurality of regions 51 and 52 is provided. 20 and a plurality of regions 51 and 52 located across the partition wall 80 emit light simultaneously.

  Here, each planar shape of the lower electrode 20, the extraction electrodes 21 and 22, the insulating film 60, the organic film 30, the upper electrode 40, the partition wall 80, and the light emitting pixel 50 on the one surface 11 of the transparent substrate 10 is the second shape described above. It is the same as that of the prototype.

  In more detail about each part, the transparent substrate 10 is an electrically insulating plate-like thing made of transparent glass or resin. The lower electrode 20, the lower electrode lead electrode 21 formed integrally therewith, and the separate upper electrode lead electrode 22 are made of the same transparent electrode material, for example, ITO (indium tin oxide) or indium zinc. It consists of a transparent conductive film such as an oxide film.

  The lower electrode 20 and the extraction electrodes 21 and 22 are formed by vapor deposition, sputtering, or the like, and are patterned so that the planar shape of the lower electrode 20 becomes an arrow shape, as in the second prototype. . The film thickness is, for example, about 100 nm to 1 μm, and preferably about 150 nm.

  The organic film 30 is formed by a vacuum deposition method, and is sequentially formed from the lower electrode 20 side, for example, a hole injection layer made of a hole injecting organic material and a positive electrode made of a hole transporting organic material. A hole transport layer, a light emitting layer made of an organic EL material doped with a fluorescent dye in a hole transport organic material or an electron transport organic material, and an electron transport layer made of an electron transport organic material are laminated.

  The organic film 30 is made of an organic material, and may have a structure that emits light when a forward bias voltage is applied between the lower electrode 20 and the upper electrode 40, and is limited to the above stacking example. is not. Similar to the second prototype, the organic film 30 is formed on substantially the entire surface other than the extraction region R while being divided by the partition wall 80.

  The upper electrode 40 can employ a cathode material that can be employed in a normal organic EL element. For example, the upper electrode 40 is made of an aluminum film having a thickness of about 100 nm and is formed by sputtering or vapor deposition.

  Similarly to the second prototype, the upper electrode 40 is also formed on substantially the entire surface other than the extraction region R while being divided by the partition wall 80. Similarly to the above, on the extraction region R side, the end of the upper electrode 40 extends from the end of the organic film 30 and covers the end of the organic film 30.

  The insulating film 60 is formed on the lower electrode 20 in the non-light emitting region 50a where the lower electrode 20 is present, and the one surface 11 of the transparent substrate 10 in a region where the lower electrode 20 outside the non-light emitting region 50a is not present. The film is formed directly on the film. In the non-light emitting region 50 a, the insulating film 60 is interposed between the lower electrode 20 and the organic film 30, and both the films 20 and 30 are electrically insulated by the insulating film 60.

  Such an insulating film 60 is generally formed of a polymer such as a photosensitive resist or polyimide, or an inorganic material such as a silicon oxide film. The insulating film 60 is formed by patterning using a technique such as photolithography or etching.

  Also in the present embodiment, the partition wall 80 is provided so as to cross the light emitting pixel 50 and completely divides the light emitting pixel 50 into a plurality of regions (here, two regions) 51 and 52. Also in this case, the partition wall 80 is formed on the lower electrode 20 in the light emitting region 50a, but is formed on the insulating film 60 in a region outside the non-light emitting region 50a and the non-light emitting region 50a. The upper electrode 40 is divided.

  Here, as shown in FIG. 2B, the partition wall 80 has a reverse taper shape that expands in a direction away from the one surface 11 side of the transparent substrate 10 (upward in FIG. 2B). The partition wall 80 is made of, for example, a negative photosensitive resin resist material.

  The cross-sectional shape of the reverse taper in the partition wall 80 is that the organic film 30 and the upper electrode 40 are appropriately defined in the step of forming the organic film 30 and the upper electrode 40 as shown in FIG. It is to do.

  Thus, in the light emitting region 50 a, that is, in the opening of the insulating film 60, the organic film 30 and the upper electrode 40 are completely divided into two regions 51 and 52 without being connected by the partition wall 80.

  Here, the plurality of regions 51 and 52 located across the partition wall 80 are both connected to the lead electrode 22 for the upper electrode and emit light simultaneously. The detailed connection configuration is shown in FIG. Please refer to.

  Here, the lead electrode 22 for the upper electrode has two portions on the upper electrode 40 side corresponding to the two regions 51 and 52, but the connection configuration of each branch portion is As shown in FIG.

  As shown in FIG. 3, an insulating film 60 is formed on one surface 11 of the transparent substrate 10 and on the lead electrode 22 for the upper electrode. Among these, the connection portion with the upper electrode 40 is formed. Since the insulating film 60 is removed, the upper electrode 40 and the extraction electrode 22 are in direct contact with each other to achieve conduction.

  In addition, as shown by an arrow L in FIG. 3, the contact portion between the two 22 and 40 may be welded with a laser L so that the two 22 and 40 are melted. Can be expected to improve the bondability between the two members 22 and 40.

  In the organic EL element 1 of this embodiment, as shown in FIG. 2, a light-shielding portion that blocks light between the partition wall 80 and the lower electrode 20 therebelow is an auxiliary of the lower electrode 20. A metal auxiliary electrode 90 configured as an electrode is provided.

  Here, the metal auxiliary electrode 90 is laminated on the lower electrode 20 and functions as an auxiliary electrode by being in direct contact with the lower electrode 20 to be conductive. The metal auxiliary electrode 90 is made of the same material as that of the upper electrode 40, such as aluminum. However, any other conductive material having a light shielding property such as an aluminum alloy or chromium may be used.

  As shown in FIG. 2, the metal auxiliary electrode 90 extends from the partition wall 80 to the stacked portion of the upper electrode 40 and the organic film 30 located on both sides of the partition wall 80 with the partition wall 80 interposed therebetween. That is, the metal auxiliary electrode 90 extends not only below the partition wall 80 but also on the surface of the lower electrode 20 in this way, and is wider than the width of the partition wall 80.

  Specifically, the wiring of the metal auxiliary electrode 90 is formed wider than the upper end width of the partition wall 80. For example, the upper end width of the partition wall 80 is 10 μm, and the wiring width of the metal auxiliary electrode 90 is 20 μm.

  The light from the light emitting pixels 50 is extracted from the other surface 12 side of the transparent substrate 10, but the light cannot be extracted at the portion where the metal auxiliary electrode 90 is formed, and becomes a non-light emitting portion. In order to prevent the non-light-emitting portion due to the metal auxiliary electrode 90 from being confirmed with the naked eye, the wiring width of the metal auxiliary electrode 90 is preferably 20 μm or less.

  Further, in the present embodiment, as shown in FIG. 2, the end portions of the metal electrode 90 located in the laminated portion of the upper electrode 40 and the organic film 30 located on both sides of the partition wall 80 are connected to the organic film 30 and the lower electrode. In this way, there is an overlapping region S1, which is a region overlapping the upper electrode 40 through the organic film 30.

  The organic EL element 1 according to this embodiment is manufactured as follows. On the surface 11 of the transparent substrate 10, film formation and patterning are performed using a general method such as sputtering, vapor deposition, CVD, photolithography, etching, and the like, and the lower electrode 20 and the extraction electrodes 21 and 22 are formed.

  A metal auxiliary electrode 90 is formed thereon by performing film formation and patterning by a general method. Next, an insulating film 60 is formed thereon by photolithography and patterning. Subsequently, the partition wall 80 is formed thereon by photolithography and patterning.

  Thereafter, when the organic film 30 and the upper electrode 40 are formed, the organic film 30 and the upper electrode 40 are formed in a state of being separated by the partition wall 80. Thus, the organic EL element of this embodiment is completed.

  Also in the light emitting pixel 50 of the present embodiment, the organic film 30 is caused to emit light by applying a voltage between the lower electrode 20 and the upper electrode 40 via the extraction electrodes 21 and 22. Specifically, a positive voltage is applied to the lower electrode 20 and a negative voltage is applied to the upper electrode 40. On the other hand, in the non-light emitting region 50a, the insulating film 60 is interposed between the lower electrode 20 and the organic film 30, so that the organic film 30 does not emit light due to the voltage application.

  Then, the light emitted from the organic film 30 is extracted through the transparent substrate 10 to the other surface 12 side opposite to the one surface 11 of the transparent substrate 10, and the user located on the other surface 12 side of the transparent substrate 10 extracts the light. It comes to be visually recognized. In the illustrated example, the arrow shape is visually recognized in accordance with the shape of the display pixel 50.

  By the way, according to the present embodiment, when the user or the like sees the organic EL element from the other surface 12 side of the transparent substrate 10 on the light extraction side, the part located between the divided regions of the light emitting pixels 50, that is, the partition wall 80 and the gap between the partition wall 80 and the organic film 30 and the upper electrode 40 are completely shielded by the metal auxiliary electrode 90.

  Specifically, by providing the metal auxiliary electrode 90 so as to form not only the lower portion of the partition wall 80 but also the overlapping region S1 with the upper electrode 40, an external portion is emitted during non-light emission as indicated by an arrow in FIG. When light is incident on the lower end of the partition wall 80, the transmission of external light can be suppressed by the metal auxiliary electrode 90, and the phenomenon of visible appearance of the back material 110 can be eliminated.

  Further, by dividing the upper electrode 40 into a plurality of regions 51 and 52 by the partition wall 80, the stress caused by the upper electrode 40 can be relaxed. In this embodiment, since the upper electrode 40 is completely divided into two regions, the stress due to the upper electrode 40 can be reduced by about 50%.

For example, although the area of the light emitting pixel 50 is about 40 mm ² , in this embodiment, by reducing the stress of the upper electrode 40 to about 50%, the luminance unevenness is reduced from about 50% to 98% without causing a problem. Can do.

  Thus, according to this embodiment, the partition electrode 80 divides the upper electrode 40 into a plurality of regions 51 and 52 to relieve the stress caused by the upper electrode 40 and to appropriately prevent the above-described visible phenomenon. Can do.

  In the present embodiment, the upper electrode 40 is completely divided into two regions 51 and 52 by the partition wall 80. However, the upper electrode can be increased by increasing the number of regions to be completely divided (for example, three regions, four regions or more). The stress due to 40 can be further relaxed. In other words, the number of regions to be divided is not limited. The larger the pixel size, the better the number of regions, and it may be selected as appropriate according to the pixel size.

  Further, according to the present embodiment, since the metal auxiliary electrode 90 functions as an auxiliary electrode of the lower electrode 20, it is possible to apparently reduce the wiring resistance of the lower electrode 20, and each region 51 in the light emitting pixel 50, The power supply to 52 can be made uniform.

  In the present embodiment, it is desirable that the upper electrode 40 and the metal auxiliary electrode 90 are made of the same material. According to this, since the reflectance can be made substantially the same between the upper electrode 40 and the metal auxiliary electrode 90, the reflected light of the external light from the other surface 12 side of the transparent substrate 10, which is the light extraction side, is reflected on the upper electrode. 40 and the metal auxiliary electrode 90 can be at substantially the same level, and the appearance is improved.

  Specifically, as shown by the arrow in FIG. 2B, the case where external light is reflected by the upper electrode 40 in the region where the upper electrode 40 other than the partition 80 is formed, and the metal auxiliary electrode The external light may be reflected by 90, and in each case, the passage path of the external light to the reflective films 40 and 90 is different.

  That is, the difference is that the external light passes through the organic film 30 in the region where the upper electrode 40 is not formed on the partition wall 80. However, since the organic film 30 is generally as thin as about 200 nm and has a transmittance of 95% or more in the entire wavelength region, the influence of the organic film 30 on the reflected light is small. That is, in the two passage paths of the external light to the reflection film, the difference in reflectance between the upper electrode 40 and the metal auxiliary electrode 90 is a main cause of the difference in reflected light.

  When the reflectance differs greatly between the upper electrode 40 and the metal auxiliary electrode 90, the reflected light of the external light from the other surface 12 side of the transparent substrate 10 that is the light extraction side differs between the upper electrode 40 and the metal auxiliary electrode 90. This difference is easily recognized by the user, but according to the present embodiment, such a difference is not recognized and the appearance is improved.

(Second Embodiment)
4A and 4B are diagrams showing a configuration of an organic EL element according to the second embodiment of the present invention, in which FIG. 4A is a schematic plan view, and FIG. 4B is a schematic diagram along a one-dot chain line DD in FIG. It is sectional drawing.

  This embodiment is different from the organic EL element 1 of the first embodiment (see FIG. 2 and the like) in that a low-resistance auxiliary electrode 100 is further added. The point will be described mainly. In FIG. 4A, the outer shape of the low-resistance auxiliary electrode 100 is indicated by a one-dot chain line.

  As shown in FIG. 4, also in the present embodiment, a non-light emitting region 50 a similar to the above is present outside the light emitting pixel 50 on the one surface 11 of the transparent substrate 10. Although not shown in the first embodiment, the cross-sectional configuration of the non-light emitting region 50a is shown in FIG. 4B in the present embodiment.

  As shown in FIG. 4B, each of the lower electrode 20, the organic film 30, and the upper electrode 40 constituting the stacked body of the light emitting pixels 50 continuously extends from the light emitting region 50a to the non-light emitting region 50a. Further, the non-light emitting region 50 a has a stacked structure in which the insulating film 60 is interposed between the lower electrode 20 and the organic film 30 in the stacked body.

  Accordingly, the light emitting pixel 50 is defined as a region inside the opening of the insulating film 60 as an inner portion of the opening, and in the non-light emitting region 50a, the organic film 30 by applying voltage to the upper and lower electrodes 20 and 40. It is supposed that no light emission occurs.

  Here, in the present embodiment, as shown in FIG. 4, in the non-light emitting region 50 a, the lower electrode 20 is made of a lower resistance material than the lower electrode 20 between the lower electrode 20 and the insulating film 60. A low-resistance auxiliary electrode 100 is provided for achieving the above.

  The low resistance auxiliary electrode 100 is made of a film having a resistance lower than that of ITO, such as Cr, and is formed by a general film formation or patterning technique. Further, the same material as the metal auxiliary electrode 90 may be used. Specifically, in the method for manufacturing the organic EL element 1 described in the first embodiment, the low-resistance auxiliary electrode 100 may be formed between the formation of the lower electrode 20 and the formation of the insulating film 60.

  According to this, the wiring resistance of the lower electrode 20 can be further reduced apparently. Specifically, the lower electrode 20 located in the non-light emitting region 50a outside the light emitting pixel 50 is a portion connected to the lead electrode 21 connected to the outside, and the low resistance auxiliary electrode 100 is provided in the portion. Thus, the wiring resistance of the portion can be reduced. And the voltage drop by resistance from the extraction electrode 21 to the light emitting pixel 50 can be made small.

(Third embodiment)
FIG. 5 is a schematic plan view of an organic EL element according to the third embodiment of the present invention. FIG. 6 is a schematic cross-sectional view taken along one-dot chain line EE in FIG.

  Although the segment pattern organic EL element has been described in the first embodiment, the present embodiment is different in that the first embodiment is applied to a passive dot matrix pattern.

  In FIG. 5, for the sake of identification, the insulating film 60 is hatched for convenience, and the metal auxiliary electrode 90 is indicated by a broken line. In FIG. 5, the insulating film 60 also exists immediately below the partition wall 80, but in FIG. 5, the portion of the insulating film 60 that overlaps with the partition wall 80 is not subjected to point hatching.

  In this dot matrix pattern, the openings of the insulating film 60 are provided in the overlapping portion of the lower electrode 20, the organic film 30, and the upper electrode 40 arranged in a plurality of stripes, so that the light emitting pixels 50 are arranged in a lattice shape. Is to be placed.

  In the example shown in FIG. 5, two lower electrodes 20 extending in the vertical direction in the drawing are shown, and four light emitting pixels 50 partitioned by partition walls 70 for light emitting pixel partitioning are shown. Here, each light emitting pixel 50 has a rectangular shape. Further, as shown in FIG. 5, also in the present embodiment, on the one surface 11 of the transparent substrate 10, a non-light emitting region 50 a similar to the above exists outside the light emitting pixel 50.

  As shown in FIGS. 5 and 6, each light emitting pixel 50 is further divided into two regions 51 and 52 by a partition wall 80 similar to that in the first embodiment. Here, the partition wall 70 for partitioning the light emitting pixel is formed by patterning integrally with the partition wall 80 using the same material.

  A desired light emitting pixel 50 is selectively made to emit light or not emit light through the extraction electrodes 21 and 22, thereby making it possible to display various information unique to the dot matrix pattern.

  Here, also in the present embodiment, as shown in FIGS. 5 and 6, the metal auxiliary electrode 90 is provided for each light emitting pixel 50. The configuration and arrangement of the metal auxiliary electrode 90 are the same as those in the first embodiment.

  Thereby, also in this embodiment, when a user etc. sees an organic EL element from the other surface 12 side of the transparent substrate 10 which is the light extraction side, the gap between the partition wall 80 and the partition wall 80 and the organic film 30 and the upper electrode 40. However, since the light is shielded by the metal auxiliary electrode 90, the back material 110 is not seen.

  Therefore, according to the present embodiment, by dividing the upper electrode 40 into the plurality of regions 51 and 52 by the partition wall 80, the stress caused by the upper electrode 40 can be relieved and the above-described phenomenon of appearance can be appropriately prevented. . Also in this embodiment, the metal auxiliary electrode 90 functions as an auxiliary electrode of the lower electrode 20, so that the wiring resistance of the lower electrode 20 can be apparently reduced.

(Fourth embodiment)
FIG. 7 is a schematic plan view of an organic EL element according to the fourth embodiment of the present invention. FIG. 8 is a schematic cross-sectional view taken along one-dot chain line FF in FIG.

  The present embodiment is different from the organic EL element having the dot matrix pattern shown in FIG. 5 of the third embodiment in that a low-resistance auxiliary electrode 100 is further added. That is, FIG. 7 is obtained by adding the low-resistance auxiliary electrode 100 to the above-described FIG. 5, and in FIG. 7, the outer shape of the low-resistance auxiliary electrode 100 is indicated by a dashed line.

  As shown in FIGS. 7 and 8, in the present embodiment, in the non-light emitting region 50a, the lower electrode 20 is made of a material having a lower resistance than the lower electrode 20 between the lower electrode 20 and the insulating film 60. A low-resistance auxiliary electrode 100 is provided for achieving the above.

  The low resistance auxiliary electrode 100 is the same as that of the second embodiment, and is made of a film having a resistance lower than that of ITO such as Cr, and is formed by a general film formation or patterning technique. Further, the same material as the metal auxiliary electrode 90 may be used. Thus, according to the present embodiment, as in the second embodiment, it is expected that the wiring resistance of the lower electrode 20 can be further reduced.

(Other embodiments)
In each of the above embodiments, the extraction electrodes 21 and 22 do not have to be made of the same material as that of the lower electrode 20 and may be formed separately from different materials.

DESCRIPTION OF SYMBOLS 1 Organic EL element 10 Transparent substrate 11 One surface of a transparent substrate 12 The other surface of a transparent substrate 20 Lower electrode 30 Organic film 40 Upper electrode 50 Light emitting pixel 50a Non-light emitting area 51, 52 The area | region of the light emitting pixel divided | segmented by the partition 80 Partition 90 Metal Auxiliary electrode 100 Low resistance auxiliary electrode S1 Overlapping region

Claims (3)

On one surface (11) of the transparent substrate (10), a lower electrode (20) made of a transparent material, an organic film (30) made of an organic material, and an upper electrode (40) made of a material that does not transmit light were sequentially laminated. A light emitting pixel (50) comprising a laminate, wherein the organic film (30) emits light by applying a voltage between the lower electrode (20) and the upper electrode (40),
In the organic EL element which takes out the light emitted from the organic film (30) to the other surface (12) side of the transparent substrate (10) through the transparent substrate (10),
In the region of the light emitting pixel (50), it extends over the lower electrode (20), divides the organic film (30) and the upper electrode (40), and divides it into a plurality of regions (51, 52). Partition wall (80) is provided on the lower electrode (20),
The plurality of regions (51, 52) located across the partition wall (80) emit light simultaneously,
A metal auxiliary electrode (90) configured as an auxiliary electrode of the lower electrode (20) is provided between the partition wall (80) and the lower electrode (20) therebelow as a light shielding portion that blocks light. And
The metal auxiliary electrode (90) is a stacked portion of the upper electrode (40) and the organic film (30) positioned on both sides of the partition wall (80) with the partition wall (80) interposed between the partition wall (80). Has spread to
An end portion of the metal auxiliary electrode (90) located in the stacked portion enters between the organic film (30) and the lower electrode (20), so that the upper portion is interposed through the organic film (30). An organic EL element characterized in that there is an overlapping region (S1) overlapping with the electrode (40).   The organic EL element according to claim 1, wherein the upper electrode (40) and the metal auxiliary electrode (90) are made of the same material. On one surface (11) of the transparent substrate (10), outside the light emitting pixel (50) is a region in which the stacked body constituting the light emitting pixel (50) is continuously expanded, A non-light emitting region in which light emission of the organic film (30) due to the voltage application does not occur by interposing an electrically insulating insulating film (60) between the lower electrode (20) and the organic film (30). 50a) exists,
The light emitting pixel (50) is defined as an inner part of the opening as a region in the opening of the insulating film (60).
In the non-light emitting region (50a), the lower electrode (20) is made of a material having a resistance lower than that of the lower electrode (20) between the lower electrode (20) and the insulating film (60). The organic EL element according to claim 1, wherein a low resistance auxiliary electrode (100) is provided.

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