JP2005202285A - Organic electroluminescence device, method for manufacturing organic electroluminescence device, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescence device reducing a wiring resistance to achieve the reduction of power consumption, suppression of heat generation and uniformalization of luminance. <P>SOLUTION: The organic electroluminescence device is provided with a switching element, 1st electrode layers 6R, 6G, 6B, a 2nd electrode layer 39, and a luminescence functional layer held among the 1st and 2nd electrode layers 6R, 6G, 6B, 39 on a substrate G. In the device, the power supply layers 36R, 36G, 36B, 37 of positive and negative electrodes for supplying power to among the 1st and 2nd electrode layers 6R, 6G, 6B, 39 are provided as layers different from wiring layers 31, 32 for driving the switching element. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic electroluminescent device, a method for manufacturing an organic electroluminescent device, and an electronic apparatus.

Conventionally, in an organic electroluminescence (hereinafter abbreviated as “organic EL”) device, a light emitting functional layer including a plurality of circuit elements, an anode, a hole injection layer and an organic EL substance (light emitting element) on a substrate, a cathode, etc. Are stacked and sealed with a sealing substrate between them and the substrate.
Specifically, indium tin oxide (ITO), tin oxide is formed on a transparent substrate such as a glass substrate on which a switching element such as a thin film transistor (hereinafter abbreviated as TFT) is formed. An anode made of a transparent conductive material such as (SnO ₂ ), a hole injection layer made of a polythiophene derivative (hereinafter abbreviated as PEDOT), a light-emitting layer made of a light-emitting substance such as polyfluorene, and Ca There are those in which a metal material having a low work function and a cathode made of a metal compound are sequentially laminated.

In such an organic EL device, if the wiring resistance connected to the anode or the cathode is large, the voltage for power supply becomes high and the power consumption increases. In addition, since heat is generated with the power supply, the organic EL material having heat-sensitive characteristics deteriorates. In addition, a voltage drop due to the wiring resistance occurs, and a difference in luminance occurs between the end portion and the center portion of the display region, resulting in a disadvantage that display quality is deteriorated.
Therefore, in order to achieve low power consumption, suppression of heat generation, and uniform luminance in the organic EL device, a technique for reducing wiring resistance has been required. In recent years, the following techniques have been proposed as techniques for realizing a reduction in wiring resistance (see, for example, Patent Documents 1, 2, and 3).
JP 2003-122270 A JP 2001-345185 A JP 2002-318556 A

However, in Patent Document 1, since plating is formed on the wiring, it is necessary to immerse in a plating solution after the panel is manufactured, and there is a problem in that the characteristics of the organic EL material having a very weak property to moisture are deteriorated. is there. In addition, there is a problem that the insulating film on the wiring must be removed.
Further, in Patent Document 2, since the auxiliary electrode is provided adjacent to the transparent electrode, when the width of the auxiliary electrode is narrow and the wiring length is long in the large screen display, the wiring resistance is increased as a result. There is a problem of end.
Further, in Patent Document 3, since auxiliary wiring is provided in the same layer as the pixel electrode, when the aperture ratio of the pixel electrode is increased as much as possible due to the nature of the display, the auxiliary wiring is consequently relatively small (thinned). ) Will end up. Therefore, the wiring resistance increases, and this technique cannot be used for a large display.

  The prior art is aimed at lowering resistance on the upper electrode (common cathode) side, and no proposal has been made for lowering resistance on the power supply line (anode) side. When realizing a current-driven display panel such as an organic EL device, it is difficult to realize a large display exceeding 40 inches, for example, for the above reasons, by reducing the resistance of only one electrode. Had.

  The present invention has been devised in view of the above-described problems, and is an organic electroluminescent device and an organic electroluminescent device capable of reducing wiring resistance, achieving low power consumption, suppressing heat generation, and achieving uniform luminance. It is an object to provide a manufacturing method and an electronic device.

In order to achieve the above object, the present invention employs the following configuration.
The organic EL device of the present invention includes a switching element, first and second electrode layers, and a light emitting functional layer sandwiched between the first and second electrode layers on a substrate. The positive and negative power supply layers for supplying power between the first and second electrode layers are provided in a layer different from a wiring layer for driving the switching element. Yes.
In this case, since the power supply layer is formed of a conductive film different from the wiring layer for driving the switching element, for example, the layer in which the signal line and the scanning line are formed, the width of the power supply line can be increased. Therefore, the resistance of the wiring can be reduced.
Therefore, in a large organic EL device (display or the like), voltage drop and heat generation due to wiring resistance can be suppressed, and the light emission luminance can be made uniform, thereby improving display quality.

The organic EL device is characterized in that the positive and negative power supply layers are formed between the substrate and the first electrode layer.
If it does in this way, there will be the same effect as the above.
Further, in the configuration in which light emitted from the light emitting functional layer is emitted from the second electrode layer side, the light emitting light is not transmitted between the substrate and the first electrode layer. Therefore, the emitted light can be emitted without hindering the transmission of the emitted light.

The organic EL device is characterized in that an insulating film is formed between the positive power supply layer and the negative power supply layer.
In this case, since the positive and negative power supply layers are formed by different layers, the area can be increased compared to the case where the positive and negative power supply layers are formed in the same layer. Therefore, low resistance can be achieved.
In particular, since the power supply layer of the negative electrode can be formed solid over substantially the entire display area, the resistance can be further reduced as compared with the power supply layer of the positive electrode. Therefore, in a large-sized organic EL device, voltage drop and heat generation due to wiring resistance can be suppressed, light emission luminance can be made uniform, and display quality can be improved.

In the organic EL device, the positive power supply layer and the negative power supply layer are formed in the same layer.
In this way, the process of forming the insulating film can be omitted, so that the manufacturing process can be simplified and the manufacturing cost can be reduced.
In the case where they are formed in the same layer as described above, the resistance can be reduced by increasing the thickness of the power supply layer within a range in which the planarization of the insulating film can be realized.

In the organic EL device, the positive power supply layer is formed on the substrate side, and the negative power supply layer is formed on the first electrode layer side.
Here, the first electrode layer is an anode, the second electrode layer is a cathode, and a hole injection layer, a light emitting element layer, an electron injection layer, and a cathode are laminated in this order from the anode side. In an organic EL device having a stacked structure, since a positive potential needs to be applied to the anode, a positive power supply layer must be connected to the source region of the driving transistor.
Therefore, since the positive power supply layer is formed on the substrate side of the negative power supply layer as shown as the feature point, the source region of the driving transistor and the positive power supply layer can be easily connected. . Similarly, since it is necessary to apply a negative potential to the cathode, the negative power supply layer can be easily connected to the cathode.

In the organic EL device, the light emitting functional layer includes light emitting elements having different emission wavelengths, and one of the positive and negative power supply layers is formed according to the light emitting element. It is a feature.
In this way, the positive and negative power supply layers can supply power to each of the light emitting elements having different emission wavelengths. It is possible to supply with different supply voltages. Therefore, the characteristics of the light emitting element can be adjusted and optimized for each emission wavelength, and the color balance, luminance, etc. can be easily optimized.

In the organic EL device, the positive and negative power supply layers and the first and second electrode layers are connected via a conductive member in a contact hole, and the contact hole is It is characterized by being provided according to the first or second electrode layer.
In this way, since the electrical connection between the positive and negative power supply layers and the first and second electrode layers can be reliably obtained, a reduction in resistance can be realized.

Moreover, the manufacturing method of the organic EL device of the invention includes a switching element, first and second electrode layers, and a light emitting functional layer sandwiched between the first and second electrode layers on a substrate. A method of manufacturing an organic EL device, comprising: forming a positive and negative power supply layer that supplies power between the first and second electrode layers, and forming the power supply layer Is different from the step of forming the wiring layer for driving the switching element.
In this way, the power supply layer is formed by a conductive layer different from the wiring layer for driving the switching element, for example, the layer in which the signal line and the scanning line are formed, so that the width of the power supply line can be widened. Thus, the resistance of the wiring can be reduced.
Therefore, in a large organic EL device (display or the like), voltage drop and heat generation due to wiring resistance can be suppressed, and the light emission luminance can be made uniform, thereby improving display quality.

In addition, an electronic apparatus according to the present invention is characterized by including the organic EL device described above.
Examples of the electronic device include an information processing device such as a mobile phone, a mobile information terminal, a clock, a word processor, and a personal computer, a TV (television), and the like.
Therefore, according to the present invention, since the display unit using the organic EL device described above is provided, the electronic apparatus includes the display unit with improved image display quality.

(First embodiment of organic EL device)
FIG. 1 is a schematic diagram showing a wiring structure of an organic EL device according to this embodiment.
The organic EL device EX is an active matrix system using TFTs as switching elements, and is an organic EL device capable of full color display that emits R (red), G (green), and B (blue) at a desired gradation. .

  As shown in FIG. 1, the organic EL device EX includes a plurality of scanning lines (wiring layers) 31... And a plurality of signal lines (wiring layers) 32 extending in a direction perpendicular to the scanning lines 31. A plurality of power supply lines (positive power supply layers) 36R, 36G, 36B,... Extending in parallel to the signal lines 32 are respectively wired, and each intersection of the scanning lines 31 and the signal lines 32. In the vicinity, pixel regions X are provided.

  A data line driving circuit 100 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 32. Further, a scanning line driving circuit 80 including a shift register and a level shifter is connected to the scanning line 31.

  Further, each of the pixel regions X is supplied with a control transistor (switching element) 1 to which a scanning signal is supplied to the gate electrode via the scanning line 31 and a signal line 32 via the control transistor 1. A storage capacitor (wiring layer) 4 for holding the pixel signal, a driving transistor (switching element) 2 to which the pixel signal held by the storage capacitor 4 is supplied to the gate electrode, and the driving transistor 2 A pixel electrode (first electrode) 6 into which a drive current flows from the power supply line 36 when electrically connected to the power supply line 36, and the pixel electrode 6 and a common cathode (second electrode) 39 are sandwiched between the pixel electrode 6 and the common cathode 39. The light emitting functional layer Y is provided. In the light emitting functional layer Y, a light emission phenomenon is caused by combining holes and electrons injected from the pixel electrode 6 and the common cathode 39. The light emitting functional layer Y includes a light emitting element having a light emitting color different from R, G, and B, and each of the power lines 36R, 36G, and 36B corresponds to the light emitting colors R, G, and B of the light emitting functional layer Y. The supply voltage at the maximum gradation is different for the light emitting elements provided and having different emission colors (emission wavelengths).

  According to the organic EL device EX, when the scanning line 31 is driven and the control transistor 1 is turned on, the potential of the signal line 32 at that time is held in the holding capacitor 4, and according to the state of the holding capacitor 4. Thus, the on / off state of the driving transistor 2 is determined. Then, current flows from the power supply line 36 to the pixel electrode 6 through the channel of the driving transistor 2, and further current flows to the common cathode 39 through the light emitting functional layer Y. The light emitting functional layer Y emits light according to the amount of current flowing through it.

  Next, specific modes of the organic EL device EX of the present embodiment will be described with reference to FIGS. FIG. 2 is a plan view for explaining the structure of the pixel region X in the organic EL device EX, and FIG. 3 is a configuration diagram for explaining the laminated structure of the organic EL device EX.

As shown in FIG. 2, a scanning line 31 and a signal line 32 extending in a direction perpendicular to the scanning line 31 are provided on a substrate G such as a glass substrate, and the scanning line 31 and the signal line 32 are provided. A control transistor 1, a driving transistor 2, and a storage capacitor 4 are provided in the vicinity of a portion where the crossing points.
Each of these members is formed by a known technique by means such as film formation, annealing, photolithography, ion implantation, and the like. A base protective film, a silicon layer, a gate insulating film, and a plurality of wiring layers are formed on a glass substrate. And an interlayer insulating film are formed and then patterned. Further, in such a laminated structure, electrical conduction is obtained between different layers by appropriately forming contact holes, and electrical conduction is obtained in the same layer by appropriately forming connection lines.
In addition, a first interlayer insulating film (not shown) is formed between the scanning line 31 and the signal line 32 and is in a non-conductive state, and a contact hole is formed in a portion that conducts between the layers. .

The control transistor 1 includes a gate electrode 11, a source electrode 12, and a drain electrode 13. The driving transistor 2 includes a gate electrode 21, a source electrode 22, and a drain electrode 23. The storage capacitor 4 includes a lower electrode 41 made of a silicon material and an upper electrode 42 made of the same wiring layer as the scanning line 31.
The gate electrode 11 is formed as a part of the scanning line 31, and the source electrode 12 is electrically connected to the signal line 32. The drain electrode 13 is connected to the gate electrode 21 of the driving transistor 2 through the first connection line 33.
The lower electrode 41 is electrically connected to power lines 36R, 36G, and 36B, which will be described later, via the second connection line 34, and the upper electrode 42 is formed integrally with the gate electrode 21 of the driving transistor 2 and is controlled from the signal line 32. The charge supplied through the transistor 1 and the connection line 33 is accumulated in the storage capacitor 4. The source electrode 22 of the driving transistor 2 is connected to the lower electrode 41 and the power supply lines 36R, 36G, and 36B via the second connection line 34. The drain electrode 23 of the driving transistor 2 is connected to a pixel electrode 6 described later via a third connection line 35.
A second interlayer insulating film (not shown) is formed on the wiring layer such as the signal line 32 and the first, second, and third connecting lines 33, 34, and 35, and the second and second interlayer insulating films are formed on the second interlayer insulating film. On the three connection lines 34 and 35, contact holes C1 and C2 are formed.

Further, as shown in FIG. 3, on the glass substrate G, a second interlayer insulating film (the outermost surface of the glass substrate G) and power lines 36R, 36G, and 36B corresponding to RGB are formed. Each of the power supply lines 36R, 36G, and 36B is electrically connected to the second connection line 34 through the contact hole C1.
In addition, a conductive electrode 6a is formed on the contact hole C2 to be electrically connected to the pixel electrode 6. The conductive electrode 6a is formed in the same process as the power supply lines 36R, 36G, and 36B, but is in a non-conductive state with the power supply lines 36R, 36G, and 36B.
Here, unlike the scanning lines 31 and the signal lines 32, the power supply lines 36R, 36G, and 36B are formed in a large area so as to sufficiently reduce the wiring resistance, and in this embodiment, have the same dimensions as the RGB pixel column width. Forming.

As materials and structures of the power supply lines 36R, 36G, and 36B, those having a low resistance metal are preferable, and a single layer of an alloy mainly composed of an Al-based metal or a laminated structure in which an Al-based metal is sandwiched is preferable. As an Al alloy, for example, an Al alloy to which Nd or Cu is added is generally known. As the laminated structure having an Al-based metal, it is preferable to adopt a structure in which a Ti film is sandwiched to improve barrier properties and prevent hillocks. Further, the same material and configuration as the scanning line 31 and the signal line 32 may be adopted. In the present embodiment, a laminated structure of Ti / Al / TiN is adopted.
As a method for forming such a material, a vacuum film formation method typified by a sputtering method is preferably employed. In addition to the sputtering method, a method in which a dispersion liquid in which various metal fine particles are dispersed in a solvent may be formed in a predetermined pattern by a droplet discharge method.

Further, a first planarization film (insulating film) 51 is formed on the power supply lines 36R, 36G, and 36B, and an auxiliary electrode (negative power supply layer) 37 is formed thereon. The first planarizing film 51 is made of polyimide resin, acrylic resin, or the like, and an organic material that can be patterned by exposure and development is generally used. In addition, the first planarization film 51 may employ an inorganic insulating material such as silicon oxide or silicon nitride as long as the unevenness on the substrate surface can be sufficiently relaxed only by the second planarization film 52 described later.
Further, the first planarizing film 51 is provided with a contact hole 51a so that the conductive electrode 6b formed together with the auxiliary electrode 37 is connected to the conductive electrode 6a described above. Yes.
The auxiliary electrode 37 functions as a negative power supply layer for the power supply lines 36R, 36G, and 36B functioning as a positive power supply layer. Such an auxiliary electrode 37 is formed in common for all the pixel regions X, unlike the power supply lines 36R, 36G, and 36B. A conductive electrode 6b is formed on the contact hole C2 to be electrically connected to the pixel electrode 6. The conduction electrode 6b is formed in the same process as the auxiliary electrode 37, but is not in conduction with the auxiliary electrode 37.

Further, a second planarizing film (insulating film) 52 is formed on the auxiliary electrode 37, and pixel electrodes 6R, 6G, and 6B are formed thereon. The second planarizing film 52 is made of polyimide resin, acrylic resin, or the like, and an organic material that can be patterned by exposure and development is generally used. The second planarization film 52 is provided with contact holes C3 and C4. The conductive electrode 6b and each pixel electrode 6 are connected by forming the contact hole C3, and the auxiliary electrode 37 and the common cathode 39 are connected by forming the contact hole C4. .
As a material for the pixel electrode 6, ITO is generally used, but the material may be changed according to the purpose. Moreover, you may employ | adopt the laminated structure which consists of the same material or a different material.
Further, when the pixel electrodes 6R, 6G, and 6B are formed, a conduction electrode 39a for conducting the auxiliary electrode 37 and the common cathode is formed at the same time.

  Furthermore, a surface insulating film 7 and a bank 8 are formed on the pixel electrodes 6R, 6G, and 6B so as to cover the boundary portions of the pixel electrodes 6R, 6G, and 6B, and the pixel electrodes 6R, 6G, and 6B are formed. The main surface of is exposed. Openings 7a and 8a are also formed in the surface insulating film 7 and the bank 8 on the contact hole C4, and the common cathode 39 and the auxiliary electrode 37 are in a conductive state via the conductive electrode 39a.

  Further, a light emitting functional layer Y (see FIG. 1) having light emitting elements that emit light of R, G, and B colors is formed on the pixel electrode 6, and a plurality of pixel regions X are formed thereon. A common cathode 39 (see FIG. 1) is formed. The common cathode 39 must be transparent in order to extract light from the light emitting layer. Therefore, ITO and IZO (Indium Zinc Oxide: IZO) are used (made by Idemitsu Kosan Co., Ltd.). However, since the electron injection property for the light emitting functional layer Y is low, It is good also as a laminated structure.

  Furthermore, a sealing thin film for blocking the influence of oxygen and moisture is formed on the common cathode 39. The sealing thin film is formed of an inorganic material, an organic material, or a material combining inorganic and organic materials. Further, on the common cathode 39 or on the sealing thin film, a light extraction structure such as a microlens or a mirror structure for changing the traveling direction of light may be provided, and further a protection made of glass, film, plastic or the like. A member may be provided.

  In the above configuration, the contact holes C3, C4, 51a and the openings 7a, 8a are formed at the positions where the pixel electrode 6 has a high opening, the pixel electrodes 6R, 6G, 6B and the common cathode 39, It is preferable that the connection resistances between the power supply lines 36R, 36G, and 36B and the auxiliary electrode 37 be reduced. In the present embodiment, the configuration formed on each side of the pixel electrodes 6R, 6G, and 6B is adopted. However, the present invention is not limited to this, and the contact holes C3, C4, 51a, Openings 7a and 8a may be formed. Further, it is not always necessary to provide these for each pixel region X. A plurality of pixel regions X may be used as a unit, and these may be provided for each unit. Further, if the contact holes C3 and C4 are formed in the non-display region, it is preferable that the contact holes C3 and C4 be formed so as to be connected in as wide an area as possible.

  In the present embodiment, since the power supply lines 36R, 36G, 36B and the auxiliary electrode 37 are formed on the lower layer side of the pixel electrode 6, light cannot be extracted to the substrate G side, and a top emission type panel is inevitably produced. Become.

  As described above, in the present embodiment, the auxiliary electrode 37 and the power supply lines 36R, 36G, and 36B are provided in layers different from the control and drive transistors 1 and 2 and the scanning lines 31 and the signal lines 32. Thus, the width of the power supply line can be increased, the resistance of the wiring can be reduced, and the current supplied to the light emitting element can be made uniform. Therefore, electric power is supplied between the pixel electrode 6 and the common cathode 39 through the auxiliary electrode 37 and the power lines 36R, 36G, and 36B with reduced resistance, and the light emitting functional layer Y can emit light well. For example, in the large-sized organic EL device EX, by adopting this configuration, it is possible to suppress voltage drop and heat generation due to wiring resistance, to make the light emission luminance uniform, and to improve display quality.

  In addition, since the auxiliary electrode 37 and the power supply lines 36R, 36G, and 36B are formed between the substrate G and the pixel electrode 6, the top emission type in which the light emitted from the light emitting functional layer Y is emitted from the common cathode 39 side. In this configuration, since the transmission of the emitted light is not hindered, the emitted light with high luminance can be emitted.

Further, since the first planarization film 51 is formed between the auxiliary electrode 37 and the power supply lines 36R, 36G, 36B, the auxiliary electrode 37 and the power supply lines 36R, 36G, 36B can be formed in different layers. Compared with the case where both are formed in the same layer, the areas of the auxiliary electrode 37 and the power supply lines 36R, 36G, and 36B can be increased, so that the resistance can be further reduced.
In particular, since the auxiliary electrode 37 can be formed in a solid shape over substantially the entire display area, the resistance can be further reduced as compared with the power supply lines 36R, 36G, and 36B. Therefore, in the large-sized organic EL device EX, voltage drop and heat generation due to wiring resistance can be suppressed, light emission luminance can be made uniform, and display quality can be improved.

  Since the power supply lines 36R, 36G, and 36B are formed on the substrate G side and the auxiliary electrode 37 is formed on the pixel electrode 6 side, the source electrode 22 of the driving transistor 2 and the power supply lines 36R, 36G, and 36B Can be easily connected. Further, the auxiliary electrode 37 can be easily connected to the common cathode 39.

  Further, since the power supply lines 36R, 36G, and 36B are formed according to the pixel electrodes 6R, 6G, and 6B, each of the light emitting elements having different emission colors between the power supply lines 36R, 36G, and 36B and the common cathode 39. Therefore, it is possible to supply different light-emitting elements with different emission colors with different supply voltages at the maximum gradation. Therefore, the characteristics of the light emitting element can be adjusted and optimized for each emission color, and the color balance, luminance, and the like can be easily optimized.

  Further, since the power supply lines 36R, 36G, 36B and the auxiliary electrode 37 are connected to the pixel electrodes 6R, 6G, 6B and the common cathode 39 through conductive members in the contact holes C3, C4, it is ensured. Conductivity can be obtained, and low resistance can be realized.

  In the present embodiment, the pixel electrodes 6R, 6G, and 6B, the light emitting functional layer Y, and the common cathode 39 are arranged from the substrate G side, but this is not a limitation. A so-called reverse structure in which the common cathode 39, the light emitting functional layer Y, and the pixel electrodes 6R, 6G, and 6B are arranged from the substrate G side may be employed.

  In the present embodiment, the light emitting functional layers Y of R, G, and B colors are arranged in a so-called stripe arrangement, but the present invention is not limited to this, and a mosaic arrangement, a delta arrangement, etc. These may be arranged in a predetermined arrangement.

  Further, in the present embodiment, the power supply lines 36R, 36G, and 36B are formed according to different light emitting elements, but it is possible to make the light emitting characteristics of the light emitting elements with respect to voltage uniform in R, G, and B. In this case, the power lines 36R, 36G, and 36B may be made common and supplied with the same voltage. If each color emits light at a desired gradation with the same voltage change amount for all of R, G, and B, the power supply lines 36R, 36G, and 36B can be shared.

  In this embodiment, the power supply lines 36R, 36G, and 36B are provided for each of R, G, and B. However, the common cathode 39 and the auxiliary electrode 37 are provided for each of R, G, and B. The power line may be shared.

(Method for manufacturing organic EL device)
Next, a method for manufacturing an organic EL device will be described with reference to FIGS.
Here, FIGS. 4 and 5 are cross-sectional views taken along the line AA ′ in the plan view of the pixel region X shown in FIG. 6 and 7 are views showing a BB ′ cross section in the plan structure diagram of the pixel region X shown in FIG.

First, a description will be given with reference to FIGS.
As shown in FIG. 4A, a driving transistor 2 including a gate electrode 21 is formed on a substrate G (not shown), and a second electrode connected to the source electrode 22 and the drain electrode 23 of the driving transistor 2 is formed. A connection line 34 and a third connection line 35 are formed. Further, a second interlayer insulating film Z is formed so as to cover the second connection line 34 and the third connection line 35. Further, contact holes C1 and C2 are formed in the second interlayer insulating film Z, and a part of the second connection line 34 and the third connection line 35 is exposed.

  Next, as shown in FIG. 4B, the power supply lines 36R, 36G, and 36B and the conductive electrodes 6a that are non-conductive with the power supply lines 36R, 36G, and 36B are formed on the interlayer insulating film Z (positive power supply). Forming the supply layer). Here, each of the power supply lines 36R, 36G, 36B is connected to the second connection line 34 through the contact hole C1. The conductive electrode 6a is connected to the second connection line 35 through the contact hole C2.

  Next, as shown in FIG. 4C, a first planarization film 51 is formed so as to cover the power supply lines 36R, 36G, and 36B and the conductive electrode 6a. Further, a contact hole 51a is formed so as to expose the conductive electrode 6a.

  Next, as shown in FIG. 4D, the auxiliary electrode 37 and the conductive electrode 6b that is non-conductive with the auxiliary electrode 37 are formed on the first planarizing film 51 (step of forming a negative power supply layer) ). Here, the conductive electrode 6b is connected to the conductive electrode 6a through the contact hole 51a.

  Next, as shown in FIG. 5A, a second planarizing film 52 is formed so as to cover the auxiliary electrode 37 and the conductive electrode 6b. Further, contact holes C3 and C4 are formed so as to expose the auxiliary electrode 37 and the conductive electrode 6b.

Next, as shown in FIG. 5B, pixel electrodes 6R, 6G, and 6B, and conductive electrodes 39a that are non-conductive with the pixel electrodes 6R, 6G, and 6B are formed. Here, each of the pixel electrodes 6R, 6G, and 6B is connected to the conductive electrode 6b through the contact hole C3, and the conductive electrode 39a is connected to the auxiliary electrode 37 through the contact hole C4.
As a result, the pixel electrodes 6R, 6G, and 6B and the power supply lines 36R, 36G, and 36B are connected via the driving transformer 2.

  Further, as shown in the figure, the surface insulating film 7 is formed so as to cover the second planarizing film 52, the pixel electrodes 6R, 6G, and 6B and the conductive electrode 39a. Further, the surface insulating film 7 in the conductive electrode 39a is removed. Here, the surface insulating film 7 is preferably made of a thin film having high lyophilicity. For example, a silicon oxide film is employed.

  Next, as shown in FIG. 5C, the bank 8 is formed so as to cover the second planarization film 52 and the pixel electrodes 6R, 6G, and 6B. The bank 8 is formed by a process such as spin coating, drying, exposure, development, and baking using a liquid material such as a photosensitive acrylic resin. By partially removing the bank 8 as shown in the figure, the conductive electrode 39a is maintained in an exposed state.

Next, as shown in FIG. 5D, a common cathode 39 is formed so as to cover the entire surface of the bank 8.
As a result, the common cathode 39 and the auxiliary electrode 37 are electrically connected.

Next, a description will be given with reference to FIGS.
As shown in FIG. 6A, a lower electrode 41 and an upper electrode 42 are formed on a substrate G (not shown). The lower electrode 41 is made of a silicon material, and the upper electrode 42 is formed on the lower electrode 41 via an insulating film. Here, the lower electrode 41 is formed simultaneously with the silicon film of the driving transistor 2, and the upper electrode 42 is formed simultaneously with the scanning line 31. Further, after forming the first interlayer insulating film covering the upper electrode 42, the signal line 32 is formed, and the second interlayer insulating film Z is formed so as to cover the signal line 32.

Next, as shown in FIG. 6B, power supply lines 36R, 36G, and 36B are formed on the interlayer insulating film Z.
Next, as shown in FIG. 6C, a first planarization film 51 is formed so as to cover the power supply lines 36R, 36G, and 36B.
Next, as illustrated in FIG. 6D, the auxiliary electrode 37 is formed so as to cover the first planarization film 51.
Next, as shown in FIG. 7A, a second planarization film 52 is formed so as to cover the auxiliary electrode 37.
Next, as shown in FIG. 7B, pixel electrodes 6R, 6G, and 6B are formed so as to cover the second planarization film 52, and the surface insulating film 7 is formed at the boundary between the pixel electrodes 6R, 6G, and 6B. Form.
Next, as shown in FIG. 7C, the bank 8 is formed corresponding to the position of the surface insulating film 7, and the light emitting functional layer Y is further formed.
Next, as shown in FIG. 7D, a common cathode 39 is formed so as to cover the entire surface of the bank 8 and the light emitting functional layer Y.

  4 to 7 includes the step of forming the light emitting functional layer Y on the surface of the pixel electrodes 6R, 6G, 6B. The light emitting functional layer Y is formed by using the droplet discharge method after the bank 8 is formed. The specific structure of the light emitting functional layer Y has a laminated structure of a hole injection layer and a light emitting element layer.

As a material for forming the hole injection layer, a conductive polymer material is preferably employed. For example, PEDOT: PSS, polythiophene, polyaniline, polypyrrole, or the like can be employed.
As a material for forming the light-emitting element layer, a known light-emitting material capable of emitting fluorescence or phosphorescence can be used. Specifically, polyfluorene derivative (PF), (poly) paraphenylene vinylene derivative (PPV), polyphenylene derivative (PP), polyparaphenylene derivative (PPP), polyvinyl carbazole (PVK), polythiophene derivative, polymethylphenylsilane A polysilane such as (PMPS) is preferably used. In addition, these polymer materials include polymer materials such as perylene dyes, coumarin dyes, rhodamine dyes, such as rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, A material such as quinacridone can be doped.
Further, the organic EL device EX of the present embodiment is configured to perform color display. That is, each light emitting element layer corresponding to the three primary colors R, G, and B is formed corresponding to each of the three primary colors, and constitutes a light emitting element layer.

Note that an electron injection material may be formed between the light emitting element layer and the common cathode 39 as necessary above the light emitting element.
It is preferable that the electron injection layer has a thickness that allows light transmission. In this way, the emitted light is not shielded by the common cathode 39, and a decrease in emission intensity can be prevented. The material for the electron injection layer is not particularly limited, and includes oxadiazole derivatives, anthraquinodimethane and its derivatives, benzoquinone and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, tetracyanoanthraquinodimethane and Examples thereof include fluorenone derivatives, diphenyldicyanoethylene and derivatives thereof, diphenoquinone derivatives, and metal complexes of 8-hydroxyquinoline and derivatives thereof. Specifically, as with the material for forming the hole transport layer, JP-A-63-70257, JP-A-63-175860, JP-A-2-135359, JP-A-2-135361, and JP-A-2-209888 are disclosed. And the like described in JP-A-3-379992 and 3-152184, particularly 2- (4-biphenylyl) -5- (4-t-butylphenyl) -1,3,4. -Oxadiazole, benzoquinone, anthraquinone, tris (8-quinolinol) aluminum are preferred.

As described above, the method for manufacturing the organic EL device includes the step of forming the power supply lines 36R, 36G, and 36B and the auxiliary electrode 37, and this step includes the step of forming the signal line 32 and the drive line. Since the process is different from the process of forming the wiring layer for driving the transistor 2, the width of the power supply lines 36R, 36G, and 36B and the auxiliary electrode 37 can be increased, and the resistance of the wiring can be reduced. be able to.
Therefore, in the large-sized organic EL device EX, voltage drop and heat generation due to wiring resistance can be suppressed, light emission luminance can be made uniform, and display quality can be improved.
By the way, although the example which used what is called a polymer type organic EL material was shown in the above-mentioned Example, it is not limited to this, A low molecular type organic EL material may be used, and depending on the case. May be used in combination of high-molecular and low-molecular organic EL materials.

(Second Embodiment of Organic EL Device)
Next, a second embodiment of the organic EL device will be described with reference to FIG.
In this embodiment, a different part from 1st Embodiment is demonstrated, the same code | symbol is attached | subjected to the same structure and description is simplified. The outline of the difference between the present embodiment and the first embodiment will be described. The power lines 36R, 36G, and 36B and the auxiliary electrode 37 of the first embodiment are formed in different layers with the first planarizing film interposed therebetween. However, in the present embodiment, the power supply lines 36R, 36G, 36B and the auxiliary electrode 37 are arranged in parallel in the same layer. In the first embodiment, the first and second planarization films 51 and 52 are necessary. However, in the present embodiment, the second planarization film 52 is not necessary, and only the first planarization film 51 is formed. Has been.

In such a configuration, since the power supply lines 36R, 36G, and 36B and the auxiliary electrode 37 are formed in the same layer, the step of forming the second planarizing film 52 can be omitted. Simplification can be achieved to reduce manufacturing costs.
In the case where they are formed in the same layer as described above, the power supply lines 36R, 36G, 36B and the auxiliary electrode 37 are made thick within the range in which the first planarization film 51 can be planarized. Can achieve low resistance. Therefore, display quality can be improved.

(Third embodiment of organic EL device)
Next, a third embodiment of the organic EL device will be described.
The basic configuration of the present embodiment is almost the same as that of the first embodiment, but the differences will be described. Common to three colors instead of the power lines 36R, 36G, and 36B provided for each RGB in the first embodiment. The configuration provided with the power line is adopted.
In this way, since the voltage supplied to the light emitting functional layer Y is the same for RGB, the resistance can be further reduced.

(Electronics)
Next, an example of an electronic apparatus including the organic EL device according to the above embodiment will be described.
FIG. 9A is a perspective view illustrating an example of a television. In FIG. 9A, reference numeral 1000 denotes a television main body, and reference numeral 1001 denotes a display unit using the organic EL device.
FIG. 9B is a perspective view showing an example of a desktop computer. In FIG. 9B, reference numeral 1200 denotes a desktop computer, reference numeral 1210 denotes a display unit using the organic EL device, reference numeral 1220 denotes an arithmetic unit including a CPU and a hard disk, reference numeral 1230 denotes an input unit including a keyboard, Reference numeral 1240 denotes an input unit composed of a mouse.
Since the electronic devices shown in FIGS. 9A and 9B include the organic EL device of the above embodiment, the electronic device includes a display unit with improved image display quality.

  Note that the electronic device is not limited to the above-described television and desktop computer, and can be applied to various electronic devices. For example, notebook computers, liquid crystal projectors, multimedia-compatible personal computers (PCs) and engineering workstations (EWS), pagers, word processors, TVs, viewfinder type or monitor direct view type video tape recorders, electronic notebooks, electronic desks The present invention can be applied to electronic devices such as a computer, a car navigation device, a POS terminal, and a device having a touch panel.

The schematic diagram which shows the wiring structure of the organic electroluminescent apparatus shown in 1st Embodiment of this invention. FIG. 2 is a plan structural view of a pixel region in the organic EL device shown in the first embodiment of the present invention. The figure for demonstrating the laminated structure of the organic electroluminescent apparatus shown in 1st Embodiment of this invention. The figure for demonstrating the manufacturing method of the organic electroluminescent apparatus shown in 1st Embodiment of this invention. The figure for demonstrating the manufacturing method of the organic electroluminescent apparatus shown in 1st Embodiment of this invention. The figure for demonstrating the manufacturing method of the organic electroluminescent apparatus shown in 1st Embodiment of this invention. The figure for demonstrating the manufacturing method of the organic electroluminescent apparatus shown in 1st Embodiment of this invention. The figure for demonstrating the laminated structure of the organic electroluminescent apparatus shown in 2nd Embodiment of this invention. The figure which shows an electronic device provided with the organic electroluminescent apparatus of this invention.

Explanation of symbols

1 ... Control transistor (switching element)
2 ... Driving transistor (switching element)
4 ... Retention capacity (wiring layer)
6: Pixel electrode (first electrode layer)
31 ... Scanning line (wiring layer)
32 ... Signal line (wiring layer)
36R, 36G, 36B ... power line (positive power supply layer)
37 ... Auxiliary electrode (negative power supply layer)
39 ... Common cathode (second electrode layer)
51. First planarizing film (insulating film)
52 ... Second planarizing film (insulating film)
C1, C2, C3, C4, 51a ... Contact hole

Claims (9)

An organic electroluminescence device comprising a switching element, a first electrode layer, a second electrode layer, and a light emitting functional layer sandwiched between the first electrode layer and the second electrode layer on a substrate,
Organic electroluminescence characterized in that a positive and negative power supply layer for supplying electric power between the first and second electrode layers is provided in a layer different from a wiring layer for driving the switching element. apparatus.   2. The organic electroluminescence device according to claim 1, wherein the positive and negative power supply layers are formed between the substrate and the first electrode layer.   The organic electroluminescence device according to claim 1, wherein an insulating film is formed between the positive power supply layer and the negative power supply layer.   The organic electroluminescence device according to claim 1, wherein the positive power supply layer and the negative power supply layer are formed in the same layer.   4. The power supply layer of the positive electrode is formed on the substrate side, and the power supply layer of the negative electrode is formed on the first electrode layer side. 5. Organic electroluminescence device. The light emitting functional layer includes light emitting elements having different emission wavelengths,
6. The organic electroluminescence device according to claim 1, wherein one of the positive and negative power supply layers is formed for each light emitting element. The positive and negative power supply layers and the first and second electrode layers are connected via a conductive member in a contact hole,
The organic electroluminescence device according to claim 1, wherein the contact hole is provided in accordance with the first or second electrode layer. A method for manufacturing an organic electroluminescence device comprising a switching element, a first electrode layer, a second electrode layer, and a light emitting functional layer sandwiched between the first electrode layer and the second electrode layer on a substrate,
Forming a positive and negative power supply layer for supplying power between the first and second electrode layers;
The process for forming the power supply layer is performed differently from the process for forming a wiring layer for driving the switching element. An electronic apparatus comprising the organic electroluminescence device according to claim 1.

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