JP2005158493A - Organic electroluminescence device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescence device having a structure by which narrower picture framing is attained after securing current supply capability to a cathode. <P>SOLUTION: The organic electroluminescence device includes a pixel electrode 111, a functional layer having a light emitting layer comprising at least an organic material, and a common cathode in this order on a substrate, a light emitting display region in which a plurality of organic EL elements are arranged in a matrix-like form, and wiring for the common cathode to supply a current to the common cathode, wherein a contact hole 30 for the common cathode which electrically connects the common cathode to the wiring for the common cathode is arranged only within the light emitting display region. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an organic electroluminescence (Electro-Luminescence, hereinafter abbreviated as EL) device and an electronic apparatus.

An organic EL element using electroluminescence has excellent features such as high visibility due to self-emission and excellent impact resistance, and thus has attracted attention as a light emitting element in various display devices. For example, in the case of a top emission type organic EL element, the organic EL element includes a first electrode (anode) made of a reflective metal film, a functional layer including an organic light emitting layer, and a second electrode (cathode) made of a transparent conductive film. ) Is generally used. In particular, in an active matrix EL element having a switching element such as a thin film transistor (hereinafter abbreviated as TFT) for driving an EL element, the first electrode is a pixel electrode connected to each TFT, The second electrode is a solid common electrode shared by a plurality of pixels arranged in a matrix. Therefore, a driving current is supplied to the first electrode (pixel electrode) through the TFT, while a driving current is supplied to the second electrode (common electrode) through the common cathode wiring connected to the common electrode. As an example of the common cathode wiring, among the four sides of the rectangular substrate, the common cathode wiring is arranged in a U shape along the other three sides excluding one side where the external connection terminals are arranged. It has been proposed (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 2003-216064

  In Patent Document 1 described above, the common cathode is formed in a solid shape on substantially the entire surface of the substrate, and the common cathode wiring is formed in the non-display area at the peripheral edge of the substrate. The common cathode and the common cathode wiring are formed in different layers. With such a configuration, a contact portion for electrically connecting the common cathode and the common cathode wiring to a region where the common cathode pattern and the common cathode wiring pattern overlap in a plane at the peripheral portion of the substrate. Was established. However, there is a requirement that the current corresponding to the emission luminance must be supplied to the common cathode, and in the configuration in which only a few cathode contact portions are provided on the substrate, each cathode contact portion has a certain size. It was necessary.

  On the other hand, in recent years, organic EL display devices have been applied to portable electronic devices such as mobile phones, and the demand for downsizing has increased with the downsizing of portable electronic devices. More specifically, there is a demand for reducing the area of the non-display area after securing the area of the predetermined display area, that is, reducing the frame. However, in the configuration as described above, a cathode contact portion having a large occupied area must be disposed in a non-display area of the substrate, that is, a frame portion outside the display area, and there is a limit to narrowing the frame. Alternatively, as a method that does not require the formation of the cathode contact portion, a method in which the cathode is extended to the end portion of the substrate and the end portion of the cathode is directly connected to the driving circuit can be considered. However, even in this method, it is necessary to form a large cathode in the non-display area, and there is a limit to narrowing the frame.

  The present invention has been made to solve the above-described problems, and has an organic EL device having a structure capable of narrowing a frame while ensuring a current supply capability to a cathode, and an electronic apparatus using the same The purpose is to provide.

In order to achieve the above object, the organic EL device of the present invention includes a first electrode, a functional layer having at least a light emitting layer made of an organic material, and a second electrode provided in this order on a substrate, An organic EL device having a light emitting display region in which organic EL elements are arranged in a matrix, wherein a conductive portion for supplying current to the second electrode is provided, and the second electrode and A connection portion that electrically connects the conductive portion is disposed only in the light emitting display region.
That is, in the organic EL device of the present invention, the connection portion (cathode contact portion in the prior art) that electrically connects the second electrode and the conductive portion is disposed only in the light emitting display region, and the substrate It is the structure which is not arrange | positioned in the non-display area | region of a peripheral part. Therefore, the frame can be narrowed because the area occupied by the connecting portion is not required. Further, in the configuration in which the connection portion is provided in the light emitting display region, for example, the connection portion can be provided for each pixel, and the current supply capability to the cathode can be sufficiently ensured.

As a more specific configuration, several patterns can be considered as to which position (layer) the conductive portion is arranged in the cross-sectional structure.
For example, a plurality of switching elements for driving the organic EL element are provided, the conductive portion is formed in a layer on the lower layer side of the switching element, and the second electrode and the conductive portion are interposed between them. A configuration in which the layers are electrically connected through a contact hole penetrating the layers can be employed. In this case, it is desirable to adopt a configuration in which the first electrode is formed of a light transmissive material and the conductive portion is formed of a metal film.
According to this configuration, since the conductive part is located on the lower layer side of the switching element and the organic EL element, a layered (solid) conductive part can be formed without interfering with the structure of these elements. As a result, the conductive portion can function as a low-resistance current supply wiring, and a highly efficient organic EL device can be realized. In particular, when the first electrode is formed of a light-transmitting material, a top emission type organic EL device is obtained, and light is not extracted downward, so that the conductive portion can be formed of an opaque metal film. In this case, the current supply wiring has a lower resistance than that of the transparent conductive film.

Alternatively, it is possible to employ a configuration in which the conductive portion is formed on the lower layer side of the second electrode, and the second electrode and the conductive portion are brought into direct contact with each other so as to be electrically connected.
In this configuration, the conductive portion is located immediately below the second electrode, and the second electrode and the conductive portion are electrically connected in direct contact with each other, and a contact hole is unnecessary. Therefore, the contact area between the second electrode and the conductive portion can be increased, and the reliability of electrical continuity is high. In addition, since the area occupied by the contact hole is not required, the area of the effective light emitting display region is increased, and the luminance of the organic EL element can be improved.

Alternatively, the conductive portion is formed in the same layer as the first electrode, and the second electrode and the conductive portion are electrically connected through a contact hole penetrating an insulating layer interposed therebetween. A configuration can be employed.
According to this configuration, since the conductive portion can be formed in the same layer as the first electrode, that is, in the same process, a special conductive portion forming step is not required, and the manufacturing process is not complicated.

Or while providing the some switching element which drives the said organic EL element, the said electroconductive part is formed in the upper layer side of the said switching element, and the lower layer side of the said 1st electrode, The said 2nd electrode and the said electroconductive part Can be electrically connected via a contact hole penetrating an insulating layer interposed therebetween.
According to this configuration, the conductive portion can be formed in a substantially layer shape (solid shape) while avoiding interference with other wirings, and a low-resistance current supply wiring is realized as in the above configuration. can do. In addition, since the conductive portion is located on the upper layer side of the switching element and the conductive portion is formed after the switching element is formed, the conductive portion is adversely affected in the switching element formation process (for example, there is a conductive portion made of metal or the like). If the crystallization annealing is performed, the heat can be easily escaped, and the annealing efficiency can be eliminated.

Further, the conductive portion may extend to the peripheral edge of the substrate, and the mounting terminal may be configured as it is.
According to this configuration, it is not necessary to form another conductive layer to form the mounting terminal, and a connection portion such as a contact between the conductive layer and the mounting terminal is not necessary. As a result, the mounting terminals can be easily formed.

An electronic apparatus according to the present invention includes the organic EL device according to the present invention.
According to this configuration, since the organic EL device with a narrow frame is provided, the electronic device can be downsized.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In all the following drawings, the scale of each layer and each member is shown to be different from the actual scale so that each layer and each member has a size that can be recognized on the drawings.

FIG. 1 is an equivalent circuit diagram showing a wiring structure of the organic EL display device of this embodiment.
As shown in FIG. 1, the organic EL display device 1 according to the present embodiment includes a plurality of scanning lines 101, a plurality of signal lines 102 extending in a direction intersecting the scanning lines 101, and the signal lines 102 extending in parallel. A plurality of power supply lines 103 are wired in a grid pattern. An area partitioned by the scanning line 101 and the signal line 102 is configured as a pixel area.
The signal line 102 is connected to a data side driving circuit 104 including a shift register, a level shifter, a video line, and an analog switch. Further, a scanning side driving circuit 105 including a shift register and a level shifter is connected to the scanning line 101.

  In each pixel region, a switching TFT 112 to which a scanning signal is supplied to the gate electrode via the scanning line 101, a holding capacitor cap for holding a pixel signal supplied from the signal line 102 via the switching TFT 112, A driving TFT 123 to which a pixel signal held by the holding capacitor cap is supplied to a gate electrode, and a pixel electrode into which a driving current flows from the power supply line 103 when electrically connected to the power supply line 103 via the driving TFT 123 111 (first electrode), a cathode 12 (second electrode), and a functional layer 110 sandwiched between the pixel electrode 111 and the cathode 12 are provided. The pixel electrode 111, the cathode 12, and the functional layer 110 constitute a light emitting portion A. The organic EL display device 1 includes a plurality of light emitting portions A in a matrix to form a light emitting display region.

  According to this configuration, when the scanning line 101 is driven and the switching TFT 112 is turned on, the potential of the signal line 102 at that time is held in the holding capacitor cap, and the driving TFT 123 of the driving TFT 123 is changed according to the state of the holding capacitor cap. The on / off state is determined. Then, current flows from the power supply line 103 to the pixel electrode 111 through the channel of the driving TFT 123, and further current flows to the cathode 12 through the functional layer 110. The functional layer 110 emits light with a luminance corresponding to the amount of current flowing therethrough.

2 is a schematic plan view of the organic EL display device 1, FIG. 3 is a plan view showing the pattern configuration of each pixel constituting the light emitting display region, and FIG. 4 is an enlarged view of the cross-sectional structure of each pixel. It is sectional drawing which follows the -A 'line.
As shown in FIG. 4, in the organic EL display device 1 of the present embodiment, a circuit element unit 14 and a display element unit 10 are sequentially stacked on a substrate 2, and the substrate surface on which the stacked body is formed is sealed by a sealing unit. It has a sealed structure. The display element unit 10 includes a pixel electrode 111 (anode, first electrode), a light emitting element unit 11 including a functional layer 110 stacked on the pixel electrode 111, and a common cathode (on the light emitting element unit 11). Second electrode) 12. The common cathode 12 and the sealing part have translucency, and the organic EL display device 1 of the present embodiment is a so-called top emission type in which display light emitted from the light emitting layer is emitted from the sealing part side. It is configured as an organic EL display device.

As shown in FIG. 2, the substrate 2 is partitioned into a light emitting display region 2a located at the center of the substrate and a non-display region 2b surrounding the light emitting display region 2a located at the periphery of the substrate.
The light emitting display area 2a is an area formed by a plurality of pixels A arranged in a matrix, and a non-display area 2b is formed so as to surround the light emitting display area 2a. In the non-display area 2b, a dummy display area adjacent to the light emitting display area 2a is formed, and a data side driving circuit (not shown), a scanning side driving circuit 105, and the like are formed. As shown in FIGS. 2 and 3, the circuit element unit 14 includes the scanning line 101, the signal line 102, the holding capacitor cap, the switching TFT 112, the driving TFT 123, and the like. The arranged pixels A are driven. One end of a wiring for supplying a signal input to the data side driving circuit, the scanning side driving circuit 105 and the like is connected to a wiring 5 a on the flexible substrate 5. The wiring 5a is connected to a driving IC 6 (driving circuit) provided on the flexible substrate 5.

Further, the above-described power supply lines 103 (103R, 103G, 103B) are wired in the non-display area 2b of the circuit element unit 14.
Further, the above-described scanning side drive circuits 105 and 105 are arranged on both sides of the light emitting display region 2a in FIG. The scanning side drive circuits 105 and 105 are provided in the circuit element section 14 below the dummy area. Further, in the circuit element section 14, a drive circuit control signal wiring 105a and a drive circuit power supply wiring 105b connected to the scanning side drive circuits 105 and 105 are provided. Further, an inspection circuit 106 is disposed above the display area 2a in FIG.

  When each pixel is enlarged, as shown in FIG. 3, the power supply line 103 and the signal line 102 are arranged to extend in the vertical direction in the drawing in parallel, and the scanning line 101 is arranged to be orthogonal to these. Yes. The semiconductor layer 20 (source) of the switching TFT 112 is connected to the signal line 102 through the contact hole 21, while the semiconductor layer 20 (drain) of the switching TFT 112 is connected to the first relay conductive layer 23 through the contact hole 22. It is connected. The semiconductor layer 25 (source) of the driving TFT 123 is connected to the power supply line 103 via the contact hole 26, while the semiconductor layer 25 (drain) of the driving TFT 123 is connected to the second relay conductive layer via the contact hole 27. 24. Further, the pixel electrode 111 is connected to the second relay conductive layer 24 through the contact hole 28. The first relay conductive layer 23 functions as a gate electrode of the driving TFT 123 at a portion where the semiconductor layer 25 of the driving TFT 123 intersects, and a portion arranged so as to overlap with the power supply line 103 is one electrode of the storage capacitor cap. Function as. Reference numeral 30 denotes a common cathode contact hole for electrically connecting a common cathode 12 (to be described later) and a common cathode wiring.

Next, a cross-sectional structure will be described with reference to FIG.
Since the organic EL display device 1 of the present embodiment is a top emission type, any of a transparent substrate, a translucent substrate, and an opaque substrate can be used for the substrate 2. Examples of the transparent or translucent substrate include glass, quartz, and resin (plastic and plastic film). As the opaque substrate, for example, a ceramic sheet such as alumina or a metal sheet such as stainless steel subjected to an insulation treatment such as surface oxidation, a thermosetting resin, a thermoplastic resin, or the like can be given.

  A first protective film 31 made of a silicon oxide film or the like, a common cathode wiring 32 (conductive portion) made of an arbitrary metal material, and a second protective film 33 made of a silicon oxide film or the like are laminated on the substrate 2. In the present embodiment, the common cathode wiring 32 is a wiring layer formed in a solid shape on substantially the entire surface of the substrate 2 although it is called a wiring. Although only the driving TFT 123 is shown in FIG. 3, the semiconductor layer 25 (silicon layer) constituting the driving TFT 123, the gate insulating film 35 made of a silicon oxide film, and the gate electrode are formed on the second protective film 33. A first relay conductive layer 23 is formed. A first interlayer insulating film 36 is formed so as to cover the driving TFT 123, and the power supply line 103 and the second relay conductive layer 24 are formed on the first interlayer insulating film 36. The power line 103 is connected to the semiconductor layer 25 (source) of the driving TFT 123 through a contact hole 26 that penetrates the first interlayer insulating film 36, while the second relay conductive layer 24 penetrates the first interlayer insulating film 36. The contact hole 25 is connected to the semiconductor layer 25 (drain) of the driving TFT 123.

  A second interlayer insulating film 37 made of a silicon oxide film is formed on the first interlayer insulating film 36 so as to cover the power supply line 103 and the second relay conductive layer 24, and a planarized insulating film made of acrylic resin or the like is formed thereon. 38 is formed. A pixel electrode 111 made of a metal having high light reflectivity such as aluminum or silver is formed on the planarization insulating film 38. Thereby, the light emitted to the substrate 2 side is efficiently emitted to the upper sealing portion side. In the case of the present embodiment, the common cathode wiring 32 is formed in a solid shape on the lower layer side of the driving TFT 123, so that the top of the common cathode wiring 32 can be obtained by using a highly light reflective metal. It can also function as a reflection layer in the emission type. In that case, the material of the pixel electrode 111 may be a transparent conductive film such as ITO. The pixel electrode 111 is connected to the second relay conductive layer 24 through a contact hole 28 that penetrates the planarization insulating film 38 and the second interlayer insulating film 37. With this configuration, the pixel electrode 111 is electrically connected to the semiconductor layer 25 (drain) of the driving TFT 123 via the second relay conductive layer 24. A peripheral portion of the pixel electrode 111 is covered with a surface insulating film 39.

  The light emitting element unit 11 mainly includes a functional layer 110 stacked on the pixel electrode 111 and a bank layer 41 (partition) provided between the adjacent pixel electrode 111 and the functional layer 110 to partition each functional layer 110. It is configured. A common cathode 12 including a transparent conductive film such as ITO is disposed on the functional layer 110, and the pixel electrode 111, the functional layer 110, and the common cathode 12 constitute a light emitting unit. The functional layer 110 includes a hole injection / transport layer stacked on the pixel electrode 111 and a light emitting layer formed on the hole injection / transport layer. For the hole injection / transport layer, for example, a mixture of a polythiophene derivative such as polyethylene dioxythiophene (PEDOT) and polystyrene sulfonic acid can be used. The light emitting layer has three types, a red light emitting layer that emits red (R), a green light emitting layer that emits green (G), and a blue light emitting layer that emits blue (B). Are arranged in stripes. As the material of the light emitting layer, cyanopyriphenylene vinylene can be used as the red light emitting layer, and polyphenylene vinylene can be used as the green light emitting layer and the blue light emitting layer. The bank layer 41 is made of acrylic resin, polyimide resin, or the like, and has an opening 41d corresponding to the position where the pixel electrode 111 is formed. Therefore, the opening 41d of the bank layer 41 becomes an effective display area that substantially contributes to display. The bank layer 41 is necessary as a partition wall when the functional layer material is formed by a droplet discharge method such as an ink jet method.

  The common cathode 12 has a two-layer structure of an electron injection layer made of bathophencesium or the like formed on the functional layer 110 and a transparent conductive film made of ITO or the like laminated thereon. In the light emitting display region 2 a, the second protective film 33, the gate insulating film 35, and the first interlayer insulation are provided in a region where various electrodes other than the common cathode wiring 32, conductive layers such as wiring, semiconductor layers, and functional layers do not exist. A common cathode contact hole 30 (connection portion) is formed so as to penetrate all of the film 36, the second interlayer insulating film 37, the planarizing insulating film 38, the surface insulating film 39, and the bank layer 41 and reach the common cathode wiring 32. ing. The solid common cathode 12 is formed along the inner wall surface of the common cathode contact hole 30 and is electrically connected by contacting the common cathode wiring 32 at the bottom of the contact hole. The upper layer of the common cathode 12 is covered with a transparent sealing resin film 43 for preventing intrusion of oxygen and moisture, and a cover glass 45 is further provided via an adhesive layer 44.

  In FIG. 4, the right side of the broken line shows the mounting terminal 47 at the end of the board. As shown in this figure, at the substrate end, a second protective film 33, a gate insulating film 35, a first interlayer insulating film 36, a second interlayer insulating film 37, and a planarizing insulating film 38, which are higher than the common cathode wiring 32, are formed. The insulating layer 39, the insulating layer such as the bank layer 41, the semiconductor layer 25, the gate electrode 23, the power supply line 103, the conductive layer such as the second relay conductive layer 24 are all removed, and the common cathode wiring 32 is formed. Exposed. That is, in the case of the present embodiment, the common cathode wiring 32 extends as it is to the end of the substrate 2 and functions as the mounting terminal 47.

    The structural feature of the organic EL display device 1 of the present embodiment is that the common cathode contact hole 30 for electrically connecting the common cathode 12 and the common cathode wiring 32 is disposed only in the light emitting display region 2a. And is not arranged in the non-display area 2b at the peripheral edge of the substrate. For this reason, it is possible to reduce the frame because the non-display area 2b does not require the area occupied by the conventional cathode contact portion. Further, since the common cathode contact hole 30 is provided outside the effective display area for each pixel, it is possible to sufficiently ensure the current supply capability to the common cathode 12 and to reduce the aperture ratio (luminance). There is nothing. In particular, in the case of the present embodiment, since the common cathode wiring 32 is located on the lower layer side of the TFT and the organic EL element, the layered (solid) common cathode wiring 32 is formed without interfering with the structure of these elements. can do. As a result, the common cathode wiring 32 can function as a low-resistance current supply wiring, and a highly efficient organic EL display device can be realized.

[Second Embodiment]
Hereinafter, a second embodiment of the present invention will be described with reference to FIG.
The basic configuration of the organic EL display device of the present embodiment is the same as that of the first embodiment, and only the common cathode wiring formation position in the cross-sectional structure is different.
FIG. 5 is a diagram showing a cross-sectional structure of the organic EL display device of the present embodiment, and corresponds to FIG. 4 of the first embodiment. In FIG. 5, the same components as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the case of the first embodiment, the common cathode wiring 32 is disposed on the lower layer side than the TFT, whereas in the case of the organic EL display device 50 of the present embodiment, as shown in FIG. The cathode wiring 51 is disposed on the upper surface of the bank layer 41. The common cathode wiring 51 is made of a metal such as chromium (Cr) / gold (Au), titanium (Ti) / copper (Cu) / titanium nitride (TiN), for example. Therefore, in the case of the present embodiment, the common cathode wiring 51 cannot be formed in a solid shape on the entire surface of the substrate, and the common cathode wiring 51 avoids an effective display area and has a predetermined pattern only on the upper surface of the bank layer 41. It is formed with. In the case of the first embodiment, the common cathode 12 is arranged on the upper layer side of the bank layer 41. However, in the case of this embodiment, the common cathode wiring 51 is arranged on the upper surface of the bank layer 41. Therefore, the common cathode 12 and the common cathode wiring 51 are in direct contact with each other. Therefore, the configuration of this embodiment is a configuration that does not require a common cathode contact hole.

  In FIG. 5, the right side of the broken line shows the mounting terminal 47 at the end of the board. As shown in this figure, at the substrate end, the first interlayer insulating film 36, the second interlayer insulating film 37, the planarizing insulating film 38, the surface insulating film 39, the insulating layer such as the bank layer 41, the semiconductor layer 25, The conductive layers such as the gate electrode 23, the power supply line 103, and the second relay conductive layer 24 are all removed, and the common cathode wiring 51 is exposed. That is, in the case of the present embodiment, the common cathode wiring 51 extends as it is to the end of the substrate and functions as the mounting terminal 47.

  In the present embodiment, since the common cathode contact hole does not exist and the common cathode 12 and the common cathode wiring 51 are joined with a certain wide contact area, the current supply capability to the common cathode 12 is sufficiently high. It can be secured and the frame can be narrowed. In particular, in the case of the present embodiment, the area of the effective display region (the opening of the bank layer) can be widened as much as the area occupied by the common cathode contact hole is not required, and the luminance of the organic EL element can be improved. it can. Moreover, since the common cathode wiring 51 is made of a metal material, the resistance of the wiring can be reduced.

[Third Embodiment]
Hereinafter, a third embodiment of the present invention will be described with reference to FIG.
The basic configuration of the organic EL display device of the present embodiment is the same as that of the first embodiment, and only the common cathode wiring formation position in the cross-sectional structure is different.
FIG. 6 is a diagram showing a cross-sectional structure of the organic EL display device of the present embodiment, and corresponds to FIG. 4 of the first embodiment. In FIG. 6, the same components as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the case of the first embodiment, the common cathode wiring 32 is arranged on the lower layer side than the TFT, and in the case of the second embodiment, the common cathode wiring 51 is arranged on the upper surface of the bank layer. On the other hand, in the case of the organic EL display device 60 of the present embodiment, the common cathode wiring 61 is disposed on the lower layer side of the bank layer 41 as shown in FIG. That is, the common cathode wiring 61 is formed in the same layer and in the same process as the pixel electrode 111 and is made of a transparent conductive film such as ITO, for example. In the light emitting display region 2 a, the surface insulating film 39 and the bank layer 41 are penetrated in a region where various electrodes other than the common cathode wiring 61, conductive layers such as wiring, the semiconductor layer 25, and the functional layer 110 do not exist. A common cathode contact hole 62 reaching the common cathode wiring 61 is formed. The solid common cathode 12 is formed along the inner wall surface of the common cathode contact hole 62 and is electrically connected by contacting the common cathode wiring 61 at the bottom of the contact hole.

  In FIG. 6, the right side of the broken line shows the mounting terminal 47 at the end of the board. As shown in this figure, at the substrate end, the first interlayer insulating film 36, the second interlayer insulating film 37, the planarizing insulating film 38, the surface insulating film 39, the insulating layer such as the bank layer 41, the semiconductor layer 25, The conductive layers such as the gate electrode 23, the power supply line 103, and the second relay conductive layer 24 are all removed, and the common cathode wiring 61 is exposed. That is, in the case of the present embodiment, the common cathode wiring 61 extends as it is to the end of the substrate and functions as the mounting terminal 47.

  Also in the present embodiment, since the common cathode contact hole 62 is provided for each pixel, it is possible to sufficiently ensure the current supply capability to the common cathode 12 and the cathode contact is provided on the peripheral edge of the substrate. Narrow frame can be achieved because it is not necessary. In particular, in the case of the present embodiment, the common cathode wiring 61 can be formed in the same layer and in the same process as the pixel electrode 111, so that a special wiring forming process is not required and the manufacturing process is not complicated.

[Fourth Embodiment]
The fourth embodiment of the present invention will be described below with reference to FIG.
The basic configuration of the organic EL display device of the present embodiment is the same as that of the first embodiment, and only the common cathode wiring formation position in the cross-sectional structure is different.
FIG. 7 is a diagram showing a cross-sectional structure of the organic EL display device of the present embodiment, and corresponds to FIG. 4 of the first embodiment. In FIG. 7, the same components as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the case of the organic EL display device 70 of the present embodiment, as shown in FIG. 7, the common cathode wiring 71 is disposed between the second interlayer insulating film 37 and the planarizing insulating film 38. The common cathode wiring 71 can be formed in a solid shape on substantially the entire surface of the substrate excluding the formation region of the TFT 123, the power supply line 103, and the second relay conductive layer 24, and can be composed of any metal material. Then, in the light emitting display region 2 a, the planarization insulating film 38, the surface insulating film 39, and the conductive layer such as various electrodes other than the common cathode wiring 71, wiring, and the like, the semiconductor layer 25, and the functional layer 110 are not present. A common cathode contact hole 72 that penetrates all of the bank layer 41 and reaches the common cathode wiring 71 is formed. A solid common cathode 12 is formed along the inner wall surface of the common cathode contact hole 72 and is electrically connected by contacting the common cathode wiring 71 at the bottom of the contact hole.

  In FIG. 7, the right side of the broken line shows the mounting terminal 47 at the end of the board. As shown in this figure, at the substrate end, the first interlayer insulating film 36, the second interlayer insulating film 37, the planarizing insulating film 38, the surface insulating film 39, the insulating layer such as the bank layer 41, the semiconductor layer 25, The conductive layers such as the gate electrode 23, the power supply line 103, and the second relay conductive layer 24 are all removed, and the common cathode wiring 71 is exposed. That is, in the case of the present embodiment, the common cathode wiring 71 extends as it is to the end of the substrate and functions as the mounting terminal 47.

  Also in the present embodiment, since the common cathode contact hole 72 is provided for each pixel, it is possible to sufficiently ensure the current supply capability to the common cathode 12 and the cathode contact is provided on the peripheral edge of the substrate. Narrow frame can be achieved because it is not necessary. In particular, in the case of the present embodiment, the common cathode wiring 71 can be formed in a substantially solid shape, so that a low-resistance current supply wiring can be realized as in the first embodiment. Further, since the common cathode wiring 71 is positioned on the upper layer side of the TFT 123 and the common cathode wiring 71 is formed after the TFT 123 is formed, the common cathode wiring 71 is adversely affected (for example, made of metal or the like) in the TFT forming process. If crystallization annealing of the Si layer of the TFT is performed in the presence of the common cathode wiring, it is possible to eliminate problems such as heat that easily escapes and annealing efficiency decreases. Further, since it is not necessary to form the common cathode contact hole 72 as deeply as in the first embodiment, there is a problem in the formation process of the common cathode contact hole 72 and a decrease in reliability in electrical connection. Absent.

[Fifth Embodiment]
Hereinafter, a fifth embodiment of the present invention will be described with reference to FIG.
The basic configuration of the organic EL display device of the present embodiment is the same as that of the first embodiment, and only the common cathode wiring formation position in the cross-sectional structure is different.
FIG. 8 is a diagram showing a cross-sectional structure of the organic EL display device of the present embodiment, and corresponds to FIG. 4 of the first embodiment. In FIG. 8, the same components as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the case of the organic EL display device 80 of the present embodiment, as shown in FIG. 8, the planarization insulating film has a two-layer structure of a first planarization insulating film 38a and a second planarization insulating film 38b. A cathode wiring 81 is disposed between the first planarization insulating film 38a and the second planarization insulating film 38b. The common cathode wiring 81 can be formed in a solid shape on substantially the entire surface of the substrate excluding the formation region of the TFT 123, the power supply line 103, and the second relay conductive layer 24, and can be made of any metal material. Then, in the light emitting display region 2a, the second planarization insulating film 38b, the surface layer insulating film are formed in a region where various electrodes other than the common cathode wiring 81, conductive layers such as wiring, the semiconductor layer 25, and the functional layer 110 are not present. 39, a common cathode contact hole 82 that penetrates all of the bank layer 41 and reaches the common cathode wiring 81 is formed. The solid common cathode 12 is formed along the inner wall surface of the common cathode contact hole 82 and is electrically connected by contacting the common cathode wiring 81 at the bottom of the contact hole.

  In FIG. 8, the right side of the broken line shows the mounting terminal 47 at the end of the board. As shown in this figure, at the substrate edge, a first interlayer insulating film 36, a second interlayer insulating film 37, a first planarizing insulating film 38a, a second planarizing insulating film 38b, a surface insulating film 39, and a bank layer Conductive layers such as the insulating layer 41, the semiconductor layer 25, the gate electrode 23, the power supply line 103, the second relay conductive layer 24, and the like are all removed, and the common cathode wiring 81 is exposed. That is, in the case of the present embodiment, the common cathode wiring 81 extends as it is to the end of the substrate and functions as the mounting terminal 47.

  Also in the present embodiment, since the common cathode contact hole 82 is provided for each pixel, it is possible to sufficiently secure the current supply capability to the common cathode 12 and the cathode contact is provided on the peripheral edge of the substrate. Narrow frame can be achieved because it is not necessary. Further, since the common cathode wiring 81 can be formed in a substantially solid shape, a low-resistance current supply wiring can be realized. Since the common cathode wiring 81 is formed after the TFT 123 is formed, the common cathode wiring 81 is common. The same effects as in the fourth embodiment can be obtained, such as eliminating the adverse effects of the cathode wiring.

[Electronics]
Hereinafter, specific examples of the electronic apparatus including the organic EL display device according to the embodiment of the present invention will be described.
FIG. 9 is a perspective view showing an example of the organic EL television 1200. In FIG. 9, reference numeral 1202 denotes a television body, reference numeral 1203 denotes a speaker, and reference numeral 1201 denotes a display unit using the organic EL display device. When the organic EL display device of the above embodiment is used for the display unit of such an electronic device, an electronic device including a display unit with a narrow frame can be realized.

The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, the specific configuration such as the planar shape and material of the common cathode wiring used in the above embodiment, the arrangement of the common cathode contact holes, and the like can be changed as appropriate. Furthermore, although the case where the R, G, and B light emitting layers are arranged in stripes has been described, the present invention is not limited to this, and various arrangement structures can be adopted. For example, in addition to the stripe arrangement, a mosaic arrangement or a delta arrangement may be used.

1 is an equivalent circuit diagram of an organic EL display device according to a first embodiment of the present invention. 2 is a plan view of the organic EL display device. FIG. It is a top view which shows the pattern of one pixel of an organic electroluminescent display apparatus similarly. It is sectional drawing which follows the AA 'line of FIG. It is sectional drawing of the organic electroluminescence display of 2nd Embodiment of this invention. It is sectional drawing of the organic electroluminescence display of 3rd Embodiment of this invention. It is sectional drawing of the organic electroluminescence display of 4th Embodiment of this invention. It is sectional drawing of the organic electroluminescence display of 5th Embodiment of this invention. It is a perspective view which shows an example of the electronic device of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,50,60,70,80 ... Organic EL display device (organic EL device), 2 ... Board | substrate, 12 ... Common cathode (2nd electrode), 30, 62, 72, 82 ... Common cathode contact hole (connection) Part), 32, 51, 61, 71, 81 ... common cathode wiring (conductive part), 110 ... functional layer, 111 ... pixel electrode (first electrode)

Claims (8)

A functional layer having a first electrode, at least a light emitting layer made of an organic material, and a second electrode are provided on the substrate in this order, and a light emitting display region in which a plurality of organic electroluminescent elements are arranged in a matrix is provided. An organic electroluminescence device,
A conductive portion for supplying a current to the second electrode is provided;
An organic electroluminescence device, wherein a connection portion for electrically connecting the second electrode and the conductive portion is disposed only in the light emitting display region.   A plurality of switching elements for driving the organic electroluminescence element are provided, the conductive portion is formed in a layer on the lower layer side of the switching element, and the second electrode and the conductive portion are interposed therebetween. The organic electroluminescence device according to claim 1, wherein the organic electroluminescence device is electrically connected through a contact hole penetrating the insulating layer.   The organic electroluminescence device according to claim 2, wherein the first electrode is made of a light-transmitting material, and the conductive portion is made of a metal film.   2. The organic material according to claim 1, wherein the conductive portion is formed on a lower layer side of the second electrode, and the second electrode and the conductive portion are electrically connected by direct contact. Electroluminescence device.   The conductive portion is formed in the same layer as the first electrode, and the second electrode and the conductive portion are electrically connected via a contact hole penetrating an insulating layer interposed therebetween. The organic electroluminescence device according to claim 1.   A plurality of switching elements for driving the organic electroluminescence element are provided, and the conductive part is formed on an upper layer side of the switching element and on a lower layer side of the first electrode, and the second electrode and the conductive part The organic electroluminescent device according to claim 1, wherein and are electrically connected through a contact hole penetrating an insulating layer interposed therebetween.   The organic electroluminescence device according to claim 1, wherein the conductive portion extends to a peripheral portion of the substrate to constitute a mounting terminal.   An electronic apparatus comprising the organic electroluminescence device according to any one of claims 1 to 7.

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