JP2008262220A - Light emitting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optical apparatus having a power-supply wiring structure that is capable of supplying sufficient electrical power to a common electrode of an electrooptical element. <P>SOLUTION: The electro-optical apparatus includes the electrooptical element having a stacked structure which includes a first electrode layer formed on the above side on an effective region 11 of a substrate 15 and a second electrode layer 14 disposed on the side of the first electrode layer, wherein a first power source line for performing voltage supply to the first electrode layer and a second power source line 16 electrically connected to the second electrode layer are included, and both of the first power source line and second power source line are disposed on the side of the effective region and the same layer as the first electrode layer, or on the under layer of the first electrode layer. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a power supply wiring structure suitable for an electro-optical device including an electro-optical element.

The organic EL element is a current-driven self-luminous element, which eliminates the need for a backlight and has the advantages of low power consumption, high viewing angle, and high contrast ratio, and is expected in the development of flat panel displays. ing. An organic EL element is an electro-optical element configured by sandwiching a light emitting layer containing a fluorescent substance between an anode and a cathode. By supplying a forward bias current between both electrodes, a positive electrode injected from the anode is provided. Self-emission occurs due to recombination energy when the holes and electrons injected from the cathode recombine. For this reason, in order to cause the organic EL element to emit light, it is necessary to supply power from an external circuit. In a conventional active matrix driving type organic EL display panel, a pixel electrode serving as an anode is disposed on each pixel provided in a pixel region, while a structure in which a cathode as a common electrode is covered over the entire pixel region is employed. It was general. For example, Japanese Patent Laid-Open No. 11-24606 (Patent Document 1) discloses a display device characterized by improving low power consumption and light emission efficiency by optimizing a wiring layout.
Japanese Patent Laid-Open No. 11-24606

However, in order to realize a display panel using an electro-optic element, the wiring resistance of the common electrode becomes a problem. In other words, if the wiring resistance of the common electrode is large, the voltage drop in the pixel at the center of the screen increases, so that sufficient current cannot be supplied near the center of the screen, making accurate gradation display difficult, and display panels The display performance is reduced. Such a problem becomes a serious problem because the wiring resistance of the common electrode increases as the display panel becomes larger. In particular, in a top emission structure that emits light from the transparent cathode side, a suitable material for a light transmissive electrode having a low resistance value similar to that of a metal layer has not yet been developed, and there is a problem in reducing the resistance of the common electrode. It has become.
Accordingly, an object of the present invention is to propose an electro-optical device and a matrix substrate having a power supply wiring structure capable of supplying sufficient power to the common electrode of the electro-optical element. It is another object of the present invention to provide an electro-optical device and a matrix substrate that can realize a narrow frame of a display panel.

  The light emitting device of the present invention includes a substrate, a plurality of scanning lines arranged in a row direction on the substrate, a plurality of data lines arranged in a column direction, and an intersection of the scanning lines and the data lines. Correspondingly arranged switching elements, a first electrode arranged above the plurality of scanning lines and the plurality of data lines, a second electrode arranged on the first electrode, and the first electrode A light emitting layer disposed between one electrode and the second electrode, and an auxiliary wiring disposed below the first electrode, wherein the auxiliary wiring is disposed in the same layer as the data line. The second electrode and the auxiliary wiring are electrically connected via a first contact hole formed in an insulating film disposed between the second electrode and the auxiliary wiring.

  The light emitting device of the present invention includes a substrate, a plurality of scanning lines arranged in a row direction on the substrate, a plurality of data lines arranged in a column direction, and an intersection of the scanning lines and the data lines. Correspondingly arranged switching elements, a first electrode arranged above the plurality of scanning lines and the plurality of data lines, a second electrode arranged on the first electrode, and the first electrode A light emitting layer disposed between one electrode and the second electrode, and an auxiliary wiring disposed below the first electrode, wherein the auxiliary wiring is disposed in the same layer as the scanning line. The second electrode and the auxiliary wiring are electrically connected via a first contact hole formed in an insulating film disposed between the second electrode and the auxiliary wiring.

  In the light emitting device of the present invention, the second electrode and the auxiliary wiring are electrically connected via a multilayer stacked structure, and the multilayer stacked structure is interposed between the second electrode and the auxiliary wiring. And an electrical connection layer formed of the same material as the first electrode, and disposed between the electrical connection layer and the auxiliary wiring, and electrically connecting the electrical connection layer and the auxiliary wiring. And the insulating film in which the first contact hole for connection is formed.

  In the light emitting device of the present invention, the multilayer stacked structure is disposed between the second electrode and the electrical connection layer, and a second contact hole for electrically connecting the second electrode and the electrical connection layer. And a bank layer formed with.

  In the electro-optical device according to the aspect of the invention, the electro-optical element is configured by a stacked structure including a first electrode layer formed above the effective region of the substrate and a second electrode layer provided above the first electrode layer. An electro-optical device, comprising: a first power supply line that supplies voltage to the first electrode layer; and a second power supply line electrically connected to the second electrode layer, wherein the first power supply line and Both of the second power supply lines are provided above the effective region and in the same layer as the first electrode layer or in a layer below the first electrode layer.

  As described above, the second electrode layer has a high resistance by forming the second power supply line electrically connected to the second electrode layer in any layer of the multilayer laminated structure laminated on the effective region of the substrate. However, sufficient power can be supplied. Further, since the electrical connection point between the second electrode layer and the second power supply line can be provided in the multilayer laminated structure, a narrow frame of the display panel can be realized.

  Here, an “electro-optical element” refers to an electronic element that changes the optical state of light by an electrical action. In addition to a self-light-emitting element such as an electroluminescence element, light deflection such as a liquid crystal element. It includes electronic elements that display gradation by changing the state. The “effective area” means an area contributing to electro-optic display on the substrate, that is, an area where an electro-optic element is to be formed, and is synonymous with the “display area” in the present embodiment. “Multilayer laminated structure” means a laminated structure composed of various thin films laminated on a substrate, and includes not only a device layer constituting an electro-optic element but also an interlayer insulating film, an electrode layer, a power supply line, and the like. . In the present invention, an electronic element such as a transistor may be interposed between the first electrode layer and the first power supply line. Further, the first power supply line and the second power supply line may be formed in the same layer (same layer) or may be formed in different layers for convenience of the manufacturing process.

  In the electro-optical device according to the aspect of the invention, it is preferable that at least a part of the first power supply line and the second power supply line are arranged in the same layer. With this configuration, the manufacturing process can be simplified.

  In the electro-optical device according to the aspect of the invention, it is preferable that the second electrode layer functions as a cathode with respect to the electro-optical element. By using the second electrode layer as a cathode, the resistance value of the cathode of the electro-optic element can be lowered.

  In the electro-optical device according to the aspect of the invention, it is preferable that the second power supply line functions as a cathode auxiliary wiring. Thereby, sufficient electric power can be supplied to the cathode of the electro-optic element.

  In the electro-optical device according to the aspect of the invention, it is preferable that the second electrode layer has translucency. Thereby, the top emission structure which inject | emits light from the 2nd electrode layer side is realizable, and an aperture ratio can be raised.

  In the electro-optical device according to the aspect of the invention, it is preferable that the second power supply line is formed in a line shape with a predetermined dispersion density in any layer constituting the multilayer stacked structure. By dispersing the second power supply line at a predetermined dispersion density, the resistance value of the second electrode layer can be lowered.

  In the electro-optical device according to the aspect of the invention, the second power supply line and the second electrode layer are formed in different layers of the multilayer stacked structure, and both are electrically connected in the multilayer stacked structure. Is preferred. By providing the electrical connection position of the second power supply line and the second electrode layer inside the multilayer structure, it is possible to realize a narrow frame of the display panel.

  In the electro-optical device according to the aspect of the invention, positions where the second power supply line and the second electrode layer are electrically connected are scattered in a plurality of locations along the extending direction of the second power supply line. preferable. By providing a plurality of electrical connection points between the second power supply line and the second electrode layer, the resistance of the second electrode layer can be reduced.

  In the electro-optical device according to the aspect of the invention, the second power supply line and the second electrode layer are formed in different layers via an interlayer insulating film, and both are electrically connected through a contact hole opened in the interlayer insulating film. It is preferable that they are connected. By forming the second electrode layer and the second power supply line in different layers of the multilayer laminated structure, the forming steps of both can be separated.

  In the electro-optical device according to the aspect of the invention, the electro-optical elements are arranged in two substantially right-angle directions, and the arrangement direction of the second power supply line is any one of the arrangement directions of the electro-optic elements arranged in two substantially right-angle directions. It is preferably substantially parallel to the arrangement direction. By making the arrangement direction of the second power supply lines parallel to the arrangement direction of the electro-optic elements, sufficient power can be supplied to the second electrode layers of the electro-optic elements arranged in two perpendicular directions.

  In the electro-optical device according to the aspect of the invention, it is preferable that the arrangement pitch of the second power supply lines is equal. By arranging the second power supply lines at equal intervals, electric power can be evenly supplied to the electro-optic elements arranged in two perpendicular directions.

  In the electro-optical device according to the aspect of the invention, it is preferable that the electro-optical element is an electroluminescence element. By using the electroluminescence element, the light emission gradation can be adjusted by current driving.

  The electronic apparatus of the present invention includes the above electro-optical device. The electronic device is not particularly limited as long as it includes a display device. For example, a mobile phone, a video camera, a personal computer, a head mounted display, a projector, a fax device, a digital camera, a portable TV, a DSP device, a PDA, It can be applied to electronic notebooks.

  A matrix substrate of the present invention is a matrix substrate for forming an electro-optic element having a multilayer laminated structure including a first electrode layer and a second electrode layer, and includes a first electrode layer formed above the substrate, A first power line for supplying voltage to the first electrode layer, and a second power line for electrically connecting to a second electrode layer to be formed above the first electrode layer, The first power supply line and the second power supply line are both provided above the effective region and in the same layer as the first electrode layer or below the first electrode layer.

  Thus, by forming the second power supply line for electrically connecting to the second electrode layer in any layer of the multilayered laminated structure of the electro-optic element to be laminated on the effective area of the substrate, Even if the resistance of the two-electrode layer is increased, a sufficient current can be supplied to the electro-optical element. In addition, since the electrical connection point between the second electrode layer and the second power supply line can be provided inside the multilayer laminated structure of the electro-optic element, a narrow frame of the display panel can be realized. Here, the “matrix substrate” refers to a wiring substrate on which an electro-optic element is not yet formed.

  In the matrix substrate of the present invention, it is preferable that at least a part of the first power supply line and the second power supply line are arranged in the same layer. With this configuration, the manufacturing process can be simplified.

  In the matrix substrate of the present invention, it is preferable that the second electrode layer functions as a cathode for the electro-optic element. By using the second electrode layer as a cathode, the resistance value of the cathode of the electro-optic element can be lowered.

  In the matrix substrate of the present invention, it is preferable that the second power supply line functions as a cathode auxiliary wiring. Thereby, sufficient electric power can be supplied to the cathode of the electro-optic element.

  In the matrix substrate of the present invention, it is preferable that the second electrode layer has translucency. Thereby, the top emission structure which inject | emits light from the 2nd electrode layer side is realizable, and an aperture ratio can be raised.

  In the matrix substrate of the present invention, it is preferable that the second power supply line is formed in a line shape with a predetermined dispersion density in any layer constituting the multilayer stacked structure. By dispersing the second power supply line at a predetermined dispersion density, the resistance value of the second electrode layer can be lowered.

  In the matrix substrate of the present invention, the second power supply line and the second electrode layer are formed in different layers of the multilayer stacked structure, and both are electrically connected in the multilayer stacked structure. preferable. By providing the electrical connection position of the second power supply line and the second electrode layer inside the multilayer structure, it is possible to realize a narrow frame of the display panel.

  In the matrix substrate of the present invention, it is preferable that the positions where the second power supply line and the second electrode layer are electrically connected are scattered in a plurality of locations along the extending direction of the second power supply line. . By providing a plurality of electrical connection points between the second power supply line and the second electrode layer, the resistance of the second electrode layer can be reduced.

  In the matrix substrate of the present invention, the second power supply line and the second electrode layer are formed in different layers via an interlayer insulating film, and both are electrically connected through a contact hole opened in the interlayer insulating film. It is preferable. By forming the second electrode layer and the second power supply line in different layers of the multilayer laminated structure, the forming steps of both can be separated.

  In the matrix substrate according to the aspect of the invention, it is preferable that the arrangement direction of the second power supply line is substantially parallel to any one of the arrangement directions of the electro-optic elements to be arranged in two substantially perpendicular directions. By making the arrangement direction of the second power supply lines parallel to the arrangement direction of the electro-optic elements, sufficient power can be supplied to the second electrode layers of the electro-optic elements arranged in two perpendicular directions.

  In the matrix substrate of the present invention, it is preferable that the arrangement pitch of the second power supply lines is equal. By arranging the second power supply lines at equal intervals, electric power can be evenly supplied to the electro-optic elements arranged in two perpendicular directions.

Embodiment 1 of the Invention
Hereinafter, this embodiment will be described with reference to the drawings.
FIG. 1 is an overall configuration diagram of an active matrix organic EL display panel 100 of the present embodiment. As shown in the figure, a scanning signal is output to a scanning line connected to a group of pixels 10 arranged in a row direction on a substrate 15 and a plurality of pixels 10 formed in a multi-layered structure formed on a display region 11. A scanning line driver 12 that performs this operation and a data line driver 13 that supplies data signals and power supply voltages to the data lines and power supply lines connected to the group of pixels 10 arranged in the column direction are arranged. The pixels 10 are arranged in two orthogonal directions of N rows and M columns, forming a pixel matrix. Each pixel 10 is formed with an organic EL element that emits light in RGB three primary colors. A cathode 14 as a common electrode is formed on the entire surface of the multi-layer structure formed on the display region 11. The material used for the cathode 14 is preferably a material that can inject as many electrons as possible, that is, a material having a low work function. As such a conductive material, a metal thin film such as calcium, lithium or aluminum is suitable.

  The organic EL display panel 100 shown in the figure is a so-called bottom emission structure type that emits light from the substrate 15 side. However, the present invention is not limited to this, and a light-transmitting conductive film is used as the cathode 14. Thus, a so-called top emission structure type in which light is emitted from the cathode 14 may be used. In the case of adopting a top emission structure, a conductive translucent metal obtained by thin-film processing a light-transmitting conductive material such as ITO as well as a metal thin film such as calcium, lithium, and aluminum as the cathode 14 so as to transmit light. Layers can be used. By using the conductive translucent metal layer, the resistance of the cathode 14 can be reduced.

FIG. 2 is a main circuit configuration diagram of the pixel 10. The pixel 10 includes a switching transistor Tr1, a driving transistor Tr2, a storage capacitor C, and a light emitting unit OLED, and is driven and controlled by a two-transistor method. The switching transistor Tr1 is an n-channel FET, the scanning terminal V _sel is connected to the gate terminal, and the data line I _dat is connected to the drain terminal. The drive transistor Tr2 is a p-channel FET, and its gate terminal is connected to the source terminal of the switching transistor Tr1. The source terminal of the transistor is connected to the power supply line _Vdd , and the drain terminal thereof is connected to the light emitting unit OLED. Further, a storage capacitor C is formed between the gate and source of the transistor. In the above configuration, when a selection signal is output to the scanning line _Vsel and the switching transistor Tr1 is opened, the data signal supplied via the data line _Idat is written in the storage capacitor C as a voltage value. Then, the holding voltage written in the holding capacitor C is held throughout one frame period, and the conductance of the driving transistor Tr2 changes in an analog manner by the holding voltage, and a forward bias current corresponding to the light emission gradation is applied to the light emitting unit OLED. Supply.

FIG. 3 is a diagram for explaining a wiring layout in the pixel region. In the present invention, in order to reduce the resistance of the cathode 14, the thin-line cathode auxiliary wiring 16 is provided in a layer different from the planar cathode 14 covering the upper surface of the multilayer laminated structure laminated on the display region 11. Then, they are electrically contacted through an interlayer insulating film. The layer for forming the cathode auxiliary wiring 16 is not particularly limited. However, in consideration of the manufacturing process of the display, the cathode auxiliary wiring 16 is formed on the same layer in the same manufacturing process as the metal wiring such as the scanning line V _sel . It can be manufactured at low cost without increasing the number of processes. The cathode auxiliary wiring 16 formed in the same process as the scanning line _Vsel can also be referred to as a gate metal layer. Further, it is preferable to use the dead space of the pixel 10 as much as possible for the position where the auxiliary cathode wiring 16 is formed. Since the dead space differs depending on the layout positions of the data line I _dat , the scanning line V _sel , the power supply line V _dd , the switching transistor Tr 1, etc., the optimum position for various layouts is selected to form the cathode auxiliary wiring 16. To do. However, if the cathode auxiliary wiring 16 is formed at a position overlapping the data line I _{dat in} a plan view, a parasitic capacitance is generated between the data line I _dat and the cathode auxiliary wiring 16, and insufficient data is written to the storage capacitor C. Therefore, the auxiliary cathode wiring 16 is formed in consideration of the positional relationship with the data line I _dat .

In the example shown in the figure, a set of scanning lines composed of two scanning lines _Vsel and the cathode auxiliary wiring 16 are alternately laid out in the row direction. That is, N / 2 auxiliary cathode wirings 16 are formed every other row. The scanning line V _sel and the cathode auxiliary wiring 16 are obtained by patterning metal wirings in the same layer, and the line width of the cathode auxiliary wiring 16 is substantially equal to the total line width of the two scanning lines V _sel. It is adjusted to be equal. On the other hand, one data line I _dat and one power supply line V _dd are wired in each column direction in the column direction. The wiring pattern shown in the figure shows one unit that is periodically repeated, and the wiring layout shown in the figure is used for every pixel 10 in the multilayer laminated structure. That is, the wiring layout of this embodiment is line symmetric with respect to an arbitrary row, and the pixel pitch is set at equal intervals in the row direction and the column direction. A switching transistor Tr1 is formed at a position where the data line I _dat and the scanning line V _sel intersect. The gate terminal of the drive transistor Tr2 is located in the extending direction of the source terminal of the transistor, and the drain terminal of the drive transistor Tr2 is electrically connected to the pixel electrode 17 through the contact hole h1. A storage capacitor C is formed on the voltage supply line V _dd in parallel with the longitudinal direction of the pixel electrode 17.

4 is a cross-sectional view taken along line AA ′ of FIG. As shown in the figure, a multilayer laminated structure 30 in which a cathode auxiliary wiring 16, an interlayer insulating film 21, a source metal layer 22, a planarizing film 20, an ITO layer 18, and a bank layer 19 are sequentially laminated on a substrate 15. Is formed. This multilayer laminated structure 30 is formed on the display area 11. A cathode 14 is formed on the upper layer of the multilayer laminated structure 30. The interlayer insulating film 21 is an insulating film for electrically separating the data line I _dat and the scanning line V _sel from the cathode auxiliary wiring 16, and is the same as the data line I _dat and the scanning line V _sel on the interlayer insulating film 21. A source metal layer 22 patterned in the process is formed in an island shape. The source metal layer 22 is electrically connected to the cathode auxiliary wiring 16 through a contact hole h5 opened in the interlayer insulating film 21. An insulating planarizing film 20 that has been planarized is laminated on the interlayer insulating film 21, and an ITO layer 18 patterned in an island shape is formed thereon. The ITO layer 18 and the source metal layer 22 are electrically connected through a contact hole h3 opened in the planarizing film 20. A plurality of contact holes h3 are opened along the extending direction of the cathode auxiliary wiring 26, and the electrical resistance value is reduced by providing many connection points between the ITO layer 18 and the source metal layer 22.

  On the other hand, a bank layer 19 made of a photosensitive organic material or the like is formed on the planarizing film 20. The bank layer 19 is a partition member that separates the individual pixels 10 and is opened under precise alignment adjustment so that the oval opening h2 is positioned on the pixel electrode 17 (see FIG. 3). A multilayer stack in which a hole transport layer and a light emitting layer are sequentially formed from the lower layer side of the substrate on the pixel electrode 17 exposed on the surface in the opening h2, and a cathode 14 as a common electrode is stacked on the display region 11. A film is formed so as to cover the upper surface of the structure 30. Thereby, the light emitting part OLED composed of the cathode / light emitting layer / hole transporting layer / pixel electrode is formed.

The laminated structure of the device layers constituting the light emitting unit OLED is not limited to the above configuration, but is cathode / light emitting layer / pixel electrode, cathode / electron transport layer / light emitting layer / pixel electrode, cathode / electron transport layer / light emitting layer / The structure may be a hole transport layer / pixel electrode or the like. That is, the hole transport layer and the electron transport layer are not necessarily essential, and these layers can be arbitrarily added. As the hole transport layer, a triphenylamine derivative (TPD), a hydrazine derivative, an arylamine derivative, or the like can be used. As the electron transporting layer, an aluminum chelate complex (Alq ₃ ), a distyryl biphenyl derivative (DPVBi), an oxadiazole derivative, a bistyrylanthracene derivative, a benzoxazole thiophene derivative, a perylene, a thiazole, or the like can be used. The light emitting layer is not limited to an organic material, and may be an inorganic material.

  On the surface of the bank layer 19, openings h <b> 4 that are opened under precise alignment adjustment at positions leading to the ITO layer 18 are scattered at a plurality of locations in the extending direction of the cathode auxiliary wiring 16. The cathode 14 formed on the bank layer 19 is electrically connected to the ITO layer 18 via the contact hole h4, and is further electrically connected to the cathode auxiliary wiring 16 via the source metal layer 22. As described above, the cathode auxiliary wiring 16 and the cathode 14 formed in the multilayer laminated structure 30 are electrically connected to each other so that the electric resistance value of the cathode 14 can be lowered and a sufficient current can be supplied to the pixel 10. It is configured.

  According to the present embodiment, it is possible to reduce the resistance value of the cathode 14, and it is possible to reduce the occurrence of luminance unevenness due to nonuniformity in the amount of current supplied to each pixel. Further, conventionally, a contact region between the cathode 14 and the power supply wiring for the cathode is provided in the frame of the display panel. However, according to the present embodiment, since the contact with the cathode 14 can be secured in the multilayer laminated structure 30, it is narrow. Frame display is possible, and a display panel with little dead space can be realized. Further, since the bank layer made of an organic material is inferior in heat resistance and chemical resistance, it is difficult to form the cathode auxiliary wiring 16 on the bank layer, but on the substrate 15 on which the FET or the like is formed. If so, metal wiring such as the auxiliary cathode wiring 16 can be easily formed.

  In this embodiment, the cathode auxiliary wiring 16 is formed at a ratio of one line per two rows. However, the present invention is not limited to this, and appropriate dispersion such as a ratio of one line per n (n is an integer of 3 or more) lines. The cathode auxiliary wiring 16 may be formed with a density. The position where the auxiliary cathode wiring 16 is formed can be formed in any layer in the multilayer laminated structure 30 and is not limited to the surface of the substrate 15.

[Embodiment 2 of the Invention]
FIG. 5 is a wiring layout diagram of the organic EL display panel 100 showing the second embodiment of the present invention. This embodiment is different from the first embodiment in that the cathode auxiliary wiring 16 is formed in the column direction. In the example shown in the figure, assuming that one pixel is composed of three RGB pixels, the cathode auxiliary wirings 16 are formed at equal intervals in the column direction at a rate of three for every two pixels. Further, two data lines I _dat are formed on both sides of the cathode auxiliary wiring 16. Two power supply lines V _dd are formed as a set in a column between adjacent cathode auxiliary wirings 16, and the total line width of one cathode auxiliary wiring 16 and two data lines I _dat The layout is made such that the total line width of the two power supply lines _Vdd is substantially equal. As a result, the wiring layout shown in the figure is configured to be line-symmetric with respect to an arbitrary column. On the other hand, one scanning line _Vsel is formed for each row in the row direction, and a switching transistor Tr1 is formed at the intersection of the scanning line _Vsel and the data line _Idat . The gate terminal of the drive transistor Tr2 is located in the extending direction of the source terminal of the transistor, and the drain terminal of the drive transistor Tr2 is electrically connected to the pixel electrode 17 through the contact hole h1. A storage capacitor C is formed on the voltage supply line V _dd in parallel with the longitudinal direction of the pixel electrode 17.

6 is a cross-sectional view taken along the line BB ′ of FIG. As shown in the figure, a multilayer laminated structure 30 in which a scanning line V _sel , an interlayer insulating film 21, a cathode auxiliary wiring 16, a planarizing film 20, an ITO layer 18, and a bank layer 19 are sequentially laminated on a substrate 15. Is formed. This multilayer laminated structure 30 is formed on the display area 11. A cathode 14 is formed on the upper layer of the multilayer stacked structure 30. The interlayer insulating film 21 is an insulating film for electrically separating the scanning line V _sel from the cathode auxiliary wiring 16, and the cathode auxiliary wiring 16 is formed in a line shape on the interlayer insulating film 21. On the planarizing film 20 formed on the cathode auxiliary wiring 16, ITO layers 18 patterned in an island shape are scattered at a plurality of locations along the extending direction of the cathode auxiliary wiring 16. A contact hole h3 is opened in the planarizing film 20, and the ITO layer 18 and the auxiliary cathode wiring 16 are configured to be conducted through the contact hole h3. A bank layer 19 made of a photosensitive organic material or the like is formed on the flat film 20, and an oval opening h2 is formed in accordance with the position of the pixel electrode 17 (see FIG. 5). As in the first embodiment, the light emitting unit OLED is formed in the opening h2.

  On the other hand, on the surface of the bank layer 19, openings h <b> 4 opened under precise alignment adjustment at positions leading to the ITO layer 18 are scattered at a plurality of locations along the extending direction of the cathode auxiliary wiring 16. The cathode 14 formed on the bank layer 19 is electrically connected to the ITO layer 18 through the contact hole h4, and is further electrically connected to the cathode auxiliary wiring 16. As described above, the plurality of auxiliary cathode wirings 16 formed in a line along the column direction of the pixels 10 and the cathodes 14 are electrically connected to each other so that a sufficient current can be supplied to the pixels 10. .

  According to the present embodiment, as in the first embodiment, the resistance value of the cathode 14 can be reduced, and the occurrence of luminance unevenness due to nonuniformity in the amount of current supplied to each pixel 10 can be reduced. Is possible. Further, since the contact between the cathode auxiliary wiring 16 and the cathode 14 can be secured inside the multilayer laminated structure 30, a narrow frame can be achieved, and a display panel with less dead space can be realized. In this embodiment, the cathode auxiliary wirings 16 are formed in a ratio of one in two rows. However, the present invention is not limited to this, and appropriate dispersion such as a ratio of one in n (n is an integer of 3 or more) columns. The cathode auxiliary wiring 16 may be formed with a density.

Embodiment 3 of the Invention
FIG. 7 is a wiring layout diagram of an organic EL display panel 100 showing a third embodiment of the present invention. This embodiment is different from the first and second embodiments in that the cathode auxiliary wiring 16 is formed in the row direction and the column direction. Here, in order to distinguish the cathode auxiliary wiring 16 formed in the row direction and the column direction for the sake of convenience, the cathode auxiliary wiring 16 formed along the row direction is referred to as a first cathode auxiliary wiring 16-1 and is arranged along the column direction. The formed cathode auxiliary wiring 16 is referred to as a second cathode auxiliary wiring 16-2. Further, the term “cathode auxiliary wiring 16” includes both unless otherwise specified. In the example shown in the figure, assuming that one pixel is constituted by three RGB pixels, the second cathode auxiliary wiring 16-2 is formed at equal intervals in the column direction at a ratio of three for every two pixels. Further, two data lines I _dat are formed on both sides of the second cathode auxiliary wiring 16-2. Two power supply lines _Vdd are formed as a set in a column between adjacent second cathode auxiliary wirings 16-2, and one second cathode auxiliary wiring 16-2 and two pieces of data are formed. The layout is made such that the total line width of the line I _{dat and} the total line width of the two power supply lines V _dd are substantially equal. As a result, the wiring layout shown in the figure is configured to be line-symmetric with respect to an arbitrary column.

On the other hand, in the row direction, a set of scanning lines composed of two scanning lines _Vsel and the first cathode auxiliary wiring 16-1 are laid out alternately. The scanning line _Vsel and the first cathode auxiliary wiring 16-1 are obtained by patterning metal wirings in a single layer, and the line width of the first cathode auxiliary wiring 16-1 is two scanning lines. The total line width of V _sel is adjusted to be approximately equal. With this configuration, the wiring layout shown in the figure is axisymmetric with respect to an arbitrary row and column.

The intersections of the scanning lines V _sel and the data line I _dat and the switching transistor Tr1 is formed, in the extending direction of the source terminal of the transistor is located the gate terminal of the driving transistor Tr2. The drain terminal of the drive transistor Tr2 is electrically connected to the pixel electrode 17 through the contact hole h1. A storage capacitor C is formed on the voltage supply line V _dd in parallel with the longitudinal direction of the pixel electrode 17.

8 is a cross-sectional view taken along the line CC ′ of FIG. As shown in the figure, a first cathode auxiliary wiring 16-1, an interlayer insulating film 21, a planarizing film 20, a source metal layer 22, an ITO layer 18, and a bank layer 19 are sequentially stacked on the substrate 15. A multilayer laminated structure 30 is formed. This multilayer laminated structure 30 is formed on the display area 11. A cathode 14 is formed on the upper layer of the multilayer stacked structure 30. The interlayer insulating film 21 is an insulating film for electrically separating the data line I _dat and the power supply line V _dd from the first cathode auxiliary wiring 16-1. A second cathode auxiliary wiring 16-2 is formed in the same layer as the data line I _dat and the power supply line V _{dd in} a direction orthogonal to the first cathode auxiliary wiring 16-1, and is opened in the interlayer insulating film 21. Both are electrically connected through the contact hole h6.

  On the interlayer insulating film 21, the source metal layer 22 is formed in islands at a plurality of locations along the extending direction of the first cathode auxiliary wiring 16-1 in the same layer as the second cathode auxiliary wiring 16-2. Yes. The source metal layer 22 is electrically connected to the first cathode auxiliary wiring 16-1 through a contact hole h5 opened in the interlayer insulating film 21. Further, the ITO layer 18 is formed on the planarizing film 20 so as to be scattered in a plurality of islands along the extending direction of the first cathode auxiliary wiring 16-1, and the source is connected through the contact hole h3. The metal layer 22 is electrically connected. A bank layer 19 made of a photosensitive organic material or the like is formed on the flat film 20, and an oval opening h2 is formed in accordance with the position of the pixel electrode 17 (see FIG. 7). As in the first embodiment, the light emitting unit OLED is formed in the opening h2. On the surface of the bank layer 19, contact holes h <b> 4 opened under precise alignment adjustment at positions that communicate with the ITO layer 18 are dotted in the extending direction of the second cathode auxiliary wiring 16-2. The cathode 14 formed on the bank layer 19 is electrically connected to the cathode auxiliary wiring 16 in the multilayer laminated structure 30, and a sufficient current can be supplied to the pixel 10 by reducing the resistance value of the cathode 14. It is configured as follows.

9 is a cross-sectional view taken along the line DD ′ of FIG. As shown in the figure, on the substrate 15, a first cathode auxiliary wiring 16-1, a scanning line V _sel , an interlayer insulating film 21, a second cathode auxiliary wiring 16-2, a planarizing film 20, an ITO layer 18, and A multilayer laminated structure 30 composed of the bank layers 19 is formed. The first cathode auxiliary wiring 16-1 and the second cathode auxiliary wiring 16-2 are formed in directions orthogonal to each other with the interlayer insulating film 21 interposed therebetween, and through a contact hole h6 opened in the interlayer insulating film 21. Are connected to each other. The planarizing film 20 laminated on the upper layer of the second cathode auxiliary wiring 16-2 is formed with a plurality of ITO layers 18 scattered in an island shape along the extending direction of the second cathode auxiliary wiring 16-2. Has been. A contact hole h3 is opened in the planarizing film 20, and the ITO layer 18 and the second cathode auxiliary wiring 16-2 are electrically connected. Further, a plurality of contact holes h4 are dotted and opened along the extending direction of the second cathode auxiliary wiring 16-2 in the bank layer 19, and the cathode 14 and the ITO layer 18 are electrically connected. In this way, the cathode 14 is electrically connected to the auxiliary cathode wiring 16 formed in two directions orthogonal to each other in the multilayer laminated structure 30, thereby greatly reducing the resistance value of the cathode 14 and providing sufficient power to the pixel 10. It is configured so that it can be supplied. For this reason, it is possible to reduce the occurrence of luminance unevenness due to non-uniformity in the amount of current supplied to the pixels 10 and realize excellent display performance. Furthermore, since the contact between the cathode auxiliary wiring 16 and the cathode 14 can be secured inside the multilayer laminated structure 30, it is possible to narrow the frame and to realize a display panel with little dead space.

[Embodiment 4 of the Invention]
FIG. 10 is a diagram illustrating an example of an electronic apparatus to which the electro-optical device of the invention can be applied. FIG. 6A shows an application example to a mobile phone. The mobile phone 230 includes an antenna unit 231, an audio output unit 232, an audio input unit 233, an operation unit 234, and the organic EL display panel 100 of the present invention. Yes. Thus, the organic EL display panel 100 of the present invention can be used as the display unit of the mobile phone 230. FIG. 2B shows an application example to a video camera. The video camera 240 includes an image receiving unit 241, an operation unit 242, an audio input unit 243, and the organic EL display panel 100 of the present invention. Thus, the organic EL display panel 100 of the present invention can be used as a finder or a display unit. FIG. 2C shows an application example to a portable personal computer. The computer 250 includes a camera unit 251, an operation unit 252, and the organic EL display panel 100 of the present invention. Thus, the organic EL display panel 100 of the present invention can be used as a display device.

  FIG. 4D shows an application example to a head mounted display. The head mounted display 260 includes a band 261, an optical system storage unit 262, and the organic EL display panel 100 of the present invention. Thus, the organic EL display panel 100 of the present invention can be used as an image display source. FIG. 6E shows an application example to a rear type projector. The projector 270 includes a housing 271, a light source 272, a composite optical system 273, a mirror 274, a mirror 275, a screen 276, and the organic EL display panel of the present invention. 100. FIG. 5F shows an application example to a front type projector. The projector 280 includes an optical system 281 and the organic EL display panel 100 of the present invention in a housing 282, and can display an image on a screen 283. . Thus, the organic EL display panel 100 of the present invention can be used as an image display source.

1 is an overall configuration diagram of an organic EL display panel of the present invention. It is a main circuit block diagram of a pixel. It is explanatory drawing of the wiring layout concerning 1st Embodiment of this invention. FIG. 4 is a cross-sectional view taken along line AA ′ in FIG. 3. It is explanatory drawing of the wiring layout concerning 2nd Embodiment of this invention. FIG. 6 is a sectional view taken along line BB ′ in FIG. 5. It is explanatory drawing of the wiring layout concerning 3rd Embodiment of this invention. It is CC 'sectional view taken on the line of FIG. FIG. 8 is a cross-sectional view taken along the line DD ′ of FIG. It is a figure which shows the example of application of the organic electroluminescent display panel of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Pixel 11 ... Pixel region 12 ... Scan line driver 13 ... Data line driver 14 ... Cathode 15 ... Substrate 16 ... Cathode auxiliary wiring 16-1 ... First cathode auxiliary wiring 16-2 ... Second cathode auxiliary wiring 17 ... Pixel electrode DESCRIPTION OF SYMBOLS 18 ... ITO layer 19 ... Bank layer 20 ... Planarization film 21 ... Interlayer insulating film 30 ... Multilayer laminated structure 100 ... Organic EL display panel Tr1 ... Switching transistor Tr2 ... Drive transistor C ... Retention capacitor OLED ... Light emitting part _Vsel ... Scanning line I _dat ... Data line V _dd ... Power supply line

Claims (4)

A substrate,
A plurality of scanning lines arranged in a row direction on the substrate; a plurality of data lines arranged in a column direction;
Switching elements arranged corresponding to the intersections of the scanning lines and the data lines;
A first electrode disposed above the plurality of scanning lines and the plurality of data lines;
A second electrode disposed on the first electrode;
A light emitting layer disposed between the first electrode and the second electrode;
An auxiliary wiring disposed on the lower side of the first electrode,
The auxiliary wiring is disposed in the same layer as the data line,
The second electrode and the auxiliary wiring are electrically connected through a first contact hole formed in an insulating film disposed between the second electrode and the auxiliary wiring. A light emitting device. A substrate,
A plurality of scanning lines arranged in a row direction on the substrate; a plurality of data lines arranged in a column direction;
Switching elements arranged corresponding to the intersections of the scanning lines and the data lines;
A first electrode disposed above the plurality of scanning lines and the plurality of data lines;
A second electrode disposed on the first electrode;
A light emitting layer disposed between the first electrode and the second electrode;
An auxiliary wiring disposed on the lower side of the first electrode,
The auxiliary wiring is disposed in the same layer as the scanning line,
The second electrode and the auxiliary wiring are electrically connected through a first contact hole formed in an insulating film disposed between the second electrode and the auxiliary wiring. A light emitting device. The light-emitting device according to claim 1 or 2,
The second electrode and the auxiliary wiring are electrically connected via a multilayer laminated structure,
The multilayer laminated structure is
An electrical connection layer disposed between the second electrode and the auxiliary wiring and made of the same material as the first electrode;
The insulating film disposed between the electrical connection layer and the auxiliary wiring, wherein the first contact hole for electrically connecting the electrical connection layer and the auxiliary wiring is formed;
A light emitting device comprising: The light-emitting device according to claim 3,
The multilayer laminated structure is
It further comprises a bank layer disposed between the second electrode and the electrical connection layer, and having a second contact hole for electrically connecting the second electrode and the electrical connection layer. Light-emitting device.

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