JP2008140573A - Electroluminescent device its manufacturing method, and electroluminescent device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electroluminescent device and its manufacturing method wherein contact resistance between a common electrode and a wiring for the common electrode can be reduced, and high brightness and high efficiency can be achieved. <P>SOLUTION: The manufacturing method of the electroluminescent device is equipped with a process of forming the wiring 12a for the common electrode electrically connected to the common electrode on a substrate 2, a process of forming an insulating membrane 240 to cover the wiring 12a for the common electrode on the substrate 2, a process of forming a pixel electrode 111 on the insulating membrane 240, a process of forming an opening part 240b reaching the wire 12a for the common electrode at the insulating membrane 240, and a process of forming the common electrode at the surface of the wiring 12a for the common electrode via the opening part 240b. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

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

  In recent years, development of electroluminescence devices using electroluminescence elements as pixels has been progressing. The electroluminescent device is capable of high-speed response with high brightness and low power consumption. Especially, organic electroluminescent devices using organic light-emitting materials are considered to be easily multicolored due to the diversity of organic compounds. It is expected to be applied to full-color displays, and is actively researched and developed. Hereinafter, “electroluminescence” is simply abbreviated as “EL”.

  The EL element has a structure in which a functional layer composed of at least one thin film including a light emitting layer is sandwiched between a pair of upper and lower electrodes. In an active matrix EL device, a functional layer is stacked over a plurality of pixel electrodes arranged in a matrix, and a common electrode common to each pixel is stacked so as to cover the functional layer. The common electrode is formed over the entire pixel portion, and is laminated on the common electrode wiring so as to cover the periphery of the substrate. The common electrode wiring and the common electrode are electrically connected at a portion where they overlap in a plane.

Here, a protective film made of the same material as the pixel electrode is disposed between the common electrode and the common electrode wiring. This protective film is not necessarily an essential component, but is an essential component when the common electrode wiring is corroded by the etching solution of the pixel electrode. For example, when ITO (indium tin oxide) is used as the pixel electrode, aqua regia is used as an etching solution for the pixel electrode. Therefore, in order to prevent corrosion of the common electrode wiring by aqua regia, the common electrode is used. It is necessary to leave ITO on the wiring for protection as a protective film. Since this protective film is not removed in the subsequent steps, the common electrode is finally laminated on the common electrode wiring via this protective film (see, for example, Patent Document 1).
JP 2005-84675 A

  However, in this structure, since a protective film having a high resistance is formed between the common electrode and the common electrode wiring, the contact resistance between the common electrode and the common electrode wiring is increased, or the common electrode is shared with the common electrode. Sufficient electrical characteristics may not be obtained due to changes in the interface characteristics with the electrode wiring. In addition, since the standard electrode potential of ITO, which is a protective film, is large, if a metal such as Al (aluminum) with a small standard electrode potential is used as a common electrode, electrolytic corrosion occurs at the contact portion between ITO and the metal, and contact occurs. In some cases, problems such as an increase in resistance or disconnection occur.

  As means for solving this problem, Patent Document 1 proposes a method of removing the ITO protective film using a special etching solution that does not corrode the common electrode wiring. However, this method requires a combination of an etching solution that does not corrode the wiring for the common electrode and a wiring material that does not corrode, and there is a problem that restrictions on process or wiring design are large. In addition, in order to form a protective film, a method of forming another protective film having high corrosion resistance to the etching solution has been proposed so that a wiring material having low corrosion resistance to the etching solution can be used. Therefore, this is not a desirable method.

  The present invention has been made in view of such circumstances, and an electroluminescence device capable of reducing contact resistance between a common electrode and a common electrode wiring and achieving high luminance and high efficiency. The purpose is to provide. It is another object of the present invention to provide a method for manufacturing an electroluminescent device capable of realizing such a structure without any restrictions in process or wiring design. Furthermore, an object of the present invention is to provide an electronic device having high reliability and excellent light emission characteristics by including such an electroluminescence device.

  In order to solve the above-described problems, an electroluminescence device of the present invention includes a functional layer including at least one layer including a light emitting layer, and a pair of electrodes including a pixel electrode and a common electrode that sandwich the functional layer. An electroluminescence device comprising: a common electrode wiring electrically connected to the common electrode; an insulating film that insulates the common electrode wiring and the common electrode; and the common electrode and the common electrode The electrode wiring is in direct contact with each other through an opening provided in the insulating film. According to this configuration, since the common electrode and the common electrode wiring are in direct contact, problems such as an increase in contact resistance and a change in interface characteristics do not occur. Therefore, an electroluminescence device having high electrical characteristics and suitable for high luminance and high efficiency can be provided.

  In the present invention, the portion of the common electrode wiring that contacts the common electrode is preferably formed of a material having a standard electrode potential closer to that of the common electrode than the pixel electrode. For example, a portion of the common electrode that contacts the common electrode wiring is formed of any metal selected from Al, Mo, Ti, W, Cr, Ta, and Mg, and the common electrode wiring common The portion that contacts the electrode is desirably formed of any metal selected from Al, Mo, Ti, W, Cr, and Ta. According to this configuration, it is possible to avoid the problem that electrolytic corrosion occurs at the contact portion between the common electrode and the common electrode wiring, resulting in an increase in contact resistance or disconnection.

  In the present invention, a terminal electrically connected to the pixel electrode or the common electrode is provided on the substrate, and a protective film formed of the same material as the pixel electrode is provided on the terminal. desirable. According to this configuration, electrical connection with low contact resistance can be realized between the terminal and the semiconductor chip, FPC, or the like while improving the mechanical strength of the terminal portion. In the terminal part, the deterioration of the electrical characteristics due to the protective film is not a problem as in the connection part between the common electrode and the common electrode wiring, and the protective film functions exclusively to prevent corrosion of the terminal. It is.

  An electroluminescence device manufacturing method according to the present invention includes a functional layer including at least one layer including a light emitting layer, and a pair of electrodes including a pixel electrode and a common electrode sandwiching the functional layer. A method of forming a common electrode wiring electrically connected to the common electrode on a substrate, and a step of forming a first insulating film covering the common electrode wiring on the substrate. Forming the pixel electrode on the first insulating film, forming a first opening reaching the common electrode wiring in the first insulating film, and the common through the first opening. Forming the common electrode on the surface of the electrode wiring. According to this method, since the common electrode and the common electrode wiring are in direct contact with each other, problems such as an increase in contact resistance and a change in interface characteristics do not occur. Therefore, an electroluminescence device having high electrical characteristics and suitable for high luminance and high efficiency can be provided. In addition, since the step of forming the first opening is performed after the patterning of the pixel electrode, the pixel electrode can be patterned without considering the corrosion of the common electrode wiring. Therefore, it is possible to provide an electroluminescence device having a high degree of freedom in element structure design, processing process, etc., and having excellent electrical characteristics and reliability.

  In the present invention, it is preferable that the step of forming the first opening is performed after the pixel electrode is formed and before the functional layer is formed. According to this method, since the first insulating film is patterned before the functional layer is formed, the functional layer is not damaged by the photo-etching process.

  In the present invention, the method includes a step of forming a partition layer on the first insulating film, and the step of forming the partition layer includes a step of forming a second insulating film that covers the pixel electrode on the first insulating film. And forming a second opening reaching the pixel electrode in the second insulating film, and forming a third opening communicating with the first opening in the second insulating film. desirable. According to this method, each light emitting region can be defined by the partition layer. In addition, when the functional layer is formed using a droplet discharge method such as an ink jet method, the partition layer functions as a partition wall that defines a region where the liquid material is disposed, and thus the liquid material is efficiently disposed in a desired region. be able to. In addition, since the third opening portion is provided in communication with the first opening portion, the area of the contact portion can be reduced, which can contribute to an increase in the aperture ratio of the pixel and a narrow frame of the panel.

  In the present invention, it is preferable that the third opening and the first opening are simultaneously formed by a common etching process. According to this method, the manufacturing process can be simplified and the manufacturing cost can be reduced as compared with the case where the first opening and the third opening are formed using different mask materials.

  In the present invention, it is preferable that the first opening, the second opening, and the third opening are simultaneously formed by a common etching process. According to this method, the manufacturing process can be simplified and the manufacturing cost can be reduced as compared with the case where the first opening, the second opening, and the third opening are formed using different mask materials. .

  The electronic apparatus of the present invention includes the electroluminescence device of the present invention described above or the electroluminescence device manufactured by the method of manufacturing the electroluminescence device of the present invention described above. According to this configuration, it is possible to provide an electronic device with high reliability and excellent light emission characteristics.

  Embodiments of the present invention will be described below with reference to the drawings. This embodiment shows one aspect of the present invention, and does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. Moreover, in the following drawings, in order to make each structure easy to understand, an actual structure and a scale, a number, and the like in each structure are different.

  In the following description, an XYZ orthogonal coordinate system is set, and the positional relationship of each member will be described with reference to the XYZ orthogonal coordinate system. At this time, the predetermined direction in the horizontal plane is the X-axis direction, the direction orthogonal to the X-axis direction in the horizontal plane is the Y-axis direction, and the direction orthogonal to each of the X-axis direction and the Y-axis direction (that is, the vertical direction) is the Z-axis direction. And

[Configuration of organic EL device]
FIG. 1 is an equivalent circuit diagram of an organic EL device 1 which is an embodiment of the EL device of the present invention. The organic EL device 1 includes a plurality of scanning lines 101 extending in the X-axis direction, a plurality of signal lines 102 extending in a direction intersecting the scanning lines 101 (Y-axis direction), and a plurality of signals extending in parallel with the signal lines 102. And a light-emitting power supply wiring 103. A pixel region A is provided near the intersection of the scanning line 101 and the signal line 102.

  A data side driving circuit 104 including a shift register, a level shifter, a video line, and an analog switch is electrically connected to the signal line 102. Each signal line 102 is electrically connected to an inspection circuit 106 including a thin film transistor. Further, a scanning side driving circuit 105 including a shift register and a level shifter is electrically connected to the scanning line 101.

  Each pixel region A is provided with a pixel circuit including a switching TFT 112, a storage capacitor Cap, a driving TFT 123, a pixel electrode (first electrode) 111, a functional layer 110, and a common electrode (second electrode) 12. It has been. In the present embodiment, the pixel electrode 111 is an anode and the common electrode 12 is a cathode. However, the pixel electrode 111 may be a cathode and the common electrode 12 may be an anode. The scanning line 101 is electrically connected to the gate electrode of the switching TFT 112. The switching TFT 112 is turned on or off in accordance with the scanning signal supplied from the scanning line 101, and the image signal supplied from the signal line 102 via the switching TFT 112 is held by the holding capacitor Cap. Yes.

  The gate electrode of the driving TFT 123 is electrically connected to the switching TFT 112 and the holding capacitor Cap, and an image signal held by the holding capacitor Cap is supplied to the gate electrode. The pixel electrode 111 is electrically connected to the driving TFT 123, and a driving current is supplied from the light emitting power supply wiring 103 through the driving TFT 123. The functional layer 110 includes at least one layer including a light emitting layer, and is sandwiched between the pixel electrode 111 and the common electrode 12. An organic EL element that is a light emitting element includes a pixel electrode 111, a functional layer 110, and a common electrode 12.

  As the functional layer 110, three types of functional layers are used: a red functional layer 110R that emits red light, a green functional layer 110G that emits green light, and a blue functional layer 110B that emits blue light. The functional layers 110R, 110G, and 110B are arranged in stripes along the Y-axis direction. The functional layers are alternately arranged in the X-axis direction in the order of the red functional layer 110R, the green functional layer 110G, and the blue functional layer 110B. Is arranged. The functional layers 110R, 110G, and 110B are electrically connected to the light emission power supply wirings 103R, 103G, and 103B through the driving TFTs 123, respectively, and the light emission power supply wirings 103R, 103G, and 103B are connected to the light emission power supply circuit 132, respectively. Electrically connected.

  A first capacitance C1 is provided between the common electrode 12 and the light-emitting power supply wirings 103R, 103G, and 103B. Charges are accumulated in the first capacitance C1, and when the potential of the drive current flowing through each light-emitting power supply wiring 103 fluctuates during driving of the organic EL device 1, the first capacitance C1. The electric charge accumulated in C1 is discharged to each light-emitting power supply wiring 103, and the potential fluctuation of the drive current is suppressed.

  In the organic EL device 1 having the above configuration, when a scanning signal is supplied from the scanning line 101 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 held in the holding capacitor Cap. The on / off state of the driving TFT 123 is determined in accordance with the applied potential. Then, a driving current flows from the light emitting power supply wirings 103R, 103G, and 103B to the pixel electrode 111 through the channel of the driving TFT 123, and further a current flows to the common electrode 12 through the functional layers 110R, 110G, and 110B. At this time, light emission corresponding to the amount of current flowing through the functional layer 110 is obtained from the functional layer 110.

  Next, the planar structure of the organic EL device 1 will be described with reference to FIG. The organic EL device 1 has a translucent substrate such as glass, quartz, or plastic as a base, and a light-emitting power supply wiring 103 (103R, 103G, 103B) and a display pixel unit 3 (one point in the figure) In the frame of the chain line). An actual display area 4 (inside the frame of the two-dot chain line in the figure) having a substantially rectangular shape in plan view including a plurality of pixels A is provided at the center of the display pixel section 3, and extends along the outer periphery of the actual display area 4. Scan line driving circuits 105 and 105 and an inspection circuit 106 are provided. On one side parallel to the X axis of the substrate 2, a terminal portion 2A in which a plurality of terminals 104 are formed is provided. Then, scanning line driving circuits 105 and 105 are provided along two sides adjacent to the one side, and an inspection circuit 106 is provided on the remaining one side. Outside the scanning line driving circuit 105, a scanning line driving circuit control signal wiring 105a and a scanning line driving circuit power supply wiring 105b that are electrically connected to the scanning line driving circuit 105 are provided.

  The display pixel unit 3 includes a central real display region 4 and a dummy region 5 (a region between the alternate long and short dash line) arranged around the actual display region 4. In the actual display area 4, a plurality of pixels A are arranged in a matrix, and the plurality of pixels A constitute an actual display area 4 that is a light emitting area. The scanning line driving circuit 105, the inspection circuit 106, the scanning line driving circuit control signal wiring 105a, and the scanning line driving circuit power supply wiring 105b are provided in the dummy region 5, and the light emitting power supply wiring 103 (103R, 103G, 103B). Is provided around the dummy region 5 (that is, around the display pixel unit 3).

  The light-emitting power supply wiring 103 is provided in an L shape in plan view along the outside of the scanning signal driving circuit control signal wiring 105 b and the inspection circuit 106. The light-emitting power supply wiring 103R connected to the red pixel (R) extends in the Y-axis direction along the scanning line driving circuit control signal wiring 105b on the left side of the drawing, and the scanning line driving circuit power supply wiring 105b is interrupted. It bends from the position to the right in the figure and extends in the X-axis direction along the outside of the inspection circuit 106. The light-emitting power supply wiring 103G or 103B connected to the green pixel (G) or the blue pixel (B) extends in the Y-axis direction along the scanning line driving circuit control signal wiring 105b on the right side of the drawing, and scan line driving. The circuit power supply wiring 105b is bent to the left in the drawing from the position where it is interrupted and extends in the X-axis direction along the outside of the inspection circuit 106. The light-emitting power supply wirings 103R, 10RG, and 103B are arranged so as to surround the three sides of the display pixel unit 3, and are electrically connected to the pixel A through wirings not shown.

  A common electrode wiring 12a is provided outside the light-emitting power supply wirings 103R, 103G, and 103B. The common electrode wiring 12a is provided in a U shape in plan view along three sides of the substrate 2 other than the side where the flexible wiring substrate 130 is provided, and surrounds the light emitting power supply wirings 103R, 103G, and 103B. Are arranged as follows. The common electrode 12 is provided on substantially the entire surface of the substrate 2 including the actual display region 4 and the region where the common electrode wiring 12a is provided, and the common electrode 12 and the common electrode wiring 12a overlap with the common electrode 12 at a portion where the common electrode 12 and the common electrode wiring 12a overlap. The common electrode wiring 12a is electrically connected.

  A wiring board 130 is electrically connected to the terminal portion 2 </ b> A of the board 2. The wiring board 130 has a flexible plastic base as a base, and a plurality of terminals 132a are provided at the side edge of the base on the board 2 side. A wiring 132 is connected to the terminal 132a, and a control IC 131 including the data side driving circuit 104, the common electrode power supply circuit 131, and the light emission power supply circuit 132 shown in FIG. . Note that a protective film formed of the same material as the pixel electrode 111 is provided over the terminal 104, and the terminal 104 and the terminal 132 a are electrically connected through this protective film.

  Next, the cross-sectional structure of the organic EL device 1 will be described with reference to FIG. 4A is a cross-sectional view of one pixel A, and FIG. 4B is a cross-sectional view of a connection portion K between the common electrode 12 and the common electrode wiring 12a.

  First, as shown in FIG. 3A, the driving TFT 123 includes a source region 123a, a drain region 123b, a channel region 123c formed in the semiconductor film 210, and a gate insulating film 220 formed on the surface of the semiconductor film. And a gate electrode 123A facing the channel region 123c.

  A first interlayer insulating film 230 covering the semiconductor film 210 and the gate insulating film 220 is formed on the substrate 2. A drain electrode 236 and a source electrode 238 are formed on the first interlayer insulating film 130, and the drain electrode 236 is formed in the contact holes 232 and 234 that penetrate the first interlayer insulating film 230 and reach the semiconductor film 210. A source electrode 238 is embedded. Each electrode 236, 238 is conductively connected to the drain region 123b and the source region 123a, respectively.

  A second interlayer insulating film 240 is formed on the first interlayer insulating film 230, and the pixel electrode 111 is formed on the second interlayer insulating film 240. A part of the pixel electrode 111 is embedded in a contact hole penetrating the second interlayer insulating film 240, and the pixel electrode 111 and the drain electrode 236 (that is, the driving TFT 123) are conductively connected through the contact hole. Yes. A first partition layer 149 made of an inorganic insulating material is formed on the second interlayer insulating film 240 so as to partially run on the peripheral edge of the pixel electrode 111. On the first partition layer 149, a second partition layer 150 made of an organic material is laminated to form a partition member in the organic EL device.

  The organic EL element 200 is configured by stacking a hole injection layer (charge transport layer) 110 </ b> A, a light emitting layer 110 </ b> B, and a common electrode 12 on the pixel electrode 111. The common electrode 12 is formed so as to cover the light emitting layer 110B and the second partition layer 150, and functions as a common electrode common to each pixel.

  In the case of a so-called top emission type organic EL device, the substrate 2 is configured to extract light from the side on which the organic EL element 200 is disposed. Therefore, in addition to a transparent substrate such as glass, an opaque substrate can also be used. . Examples of opaque substrates include ceramics such as alumina, metal sheets such as stainless steel that have been subjected to insulation treatment such as surface oxidation, thermosetting resins and thermoplastic resins, and films thereof (plastic films). It is done.

  The pixel electrode 111 is formed of a light-transmitting conductive material such as ITO (indium tin oxide) in the case of the bottom emission type in which light is extracted through the substrate 2. It is not necessary to have a property, and it can be formed of an appropriate conductive material such as a metal material.

  The common electrode 12 is formed on the substrate 2 so as to cover the upper surfaces of the light emitting layer 110 </ b> B and the second partition layer 150, and the wall surfaces forming the side portions of the second partition layer 150. As a material for forming the common electrode 12, in the case of the top emission type, a transparent conductive material is used. ITO is suitable as the transparent conductive material, but other translucent conductive materials may be used.

  A protective layer may be formed on the upper layer side of the common electrode 12. The protective layer can be formed of an inorganic compound such as a silicon compound such as silicon oxide, silicon nitride, or silicon nitride oxide. By covering the common electrode 12 with a protective layer made of an inorganic compound, intrusion of oxygen or the like into the common electrode 12 made of an inorganic oxide can be satisfactorily prevented.

  Next, referring to the cross-sectional structure of FIG. 3B, the common electrode wiring 12 a is formed on the first interlayer insulating film 230. The common electrode wiring 12a is formed in the same process as the source electrode 238 and the drain electrode 236, for example. A second interlayer insulating film 240 is formed on the first interlayer insulating film 230 so as to cover the common electrode wiring 12a. An inorganic insulating material constituting the first partition layer 149 is formed on the second interlayer insulating film 240. Is formed. Further, the common electrode 12 is formed on the inorganic insulating material 149, and the common electrode 12 and the common electrode wiring 12a are in contact with each other through a contact hole penetrating the inorganic insulating material 149 and the second interlayer insulating film 240. Thus, the common electrode 12 and the common electrode wiring 12a are electrically connected.

  As described above, in the organic EL device 1 of the present embodiment, the common electrode 12 and the common electrode wiring 12a are in direct contact with each other. Compared with the case of connecting through a protective film, a better electrical connection can be made. In addition, since the common electrode 12 and the common electrode wiring 12a are formed of a material having a standard electrode potential, it is possible to prevent the occurrence of electrolytic corrosion at the contact portion between the common electrode 12 and the common electrode wiring 12a. A highly reliable organic EL device can be provided.

  In addition, since the protective film formed of the same material as the pixel electrode 111 is provided over the terminal 104, the mechanical strength of the terminal 104 can be improved and the contact resistance between the terminal 104 and the terminal 132a can be improved. A small electrical connection can be realized. In the connection portion of the terminal portion 2A, the deterioration of the electrical characteristics due to the protective film is not a problem as in the connection portion between the common electrode 12 and the common electrode wiring 12a, and the protective film has the mechanical strength of the terminal 104. This is because it functions as an improvement and prevention of corrosion.

[Method for Manufacturing Organic EL Device]
Next, a method for manufacturing the organic EL device 1 will be described with reference to FIGS. 4 and 5, the left side shows the pixel region A, and the right side shows the connection portion K between the common electrode 12 and the common electrode wiring 12a.

  First, as shown in FIG. 4A, the driving TFT 123 is formed on the substrate 2. A first interlayer insulating film 230 made of an inorganic insulating material such as silicon oxide is formed so as to cover the driving TFT, and contact holes 234 and 232 reaching the source region 123b and the drain region 123a are formed in the first interlayer insulating film 230. Form.

  Next, a source electrode 238 and a drain electrode 236 that are electrically connected to the source region 123b and the drain region 123a through the contact holes 234 and 232, respectively, are formed on the first interlayer insulating film 230. At the same time, the common electrode wiring 12 a is formed on the first interlayer insulating film 230. The common electrode wiring 12a is formed of a material having a standard electrode potential close to that of the common electrode 12. Specifically, it is formed of any metal selected from Al, Mo, Ti, W, Cr, and Ta. Or it is good also as a structure which has a cap layer of these metals on Al. In the present embodiment, the common electrode wiring 12a is simultaneously formed in the same layer as the source electrode 238 and the drain electrode 236, but it is not always necessary to form these simultaneously.

  Next, a second interlayer insulating film (first insulating film) 240 is formed on the first interlayer insulating film 230 to cover the source electrode 238, the drain electrode 236, and the common electrode wiring 12a. The second interlayer insulating film 240 is formed of an inorganic insulating material such as silicon oxide or silicon oxynitride. Subsequently, a contact hole 240 a reaching the source electrode 238 is formed in the second interlayer insulating film 240.

  Next, as illustrated in FIG. 4B, the pixel electrode 111 that is electrically connected to the drain electrode 236 through the contact hole 240 a is formed on the second interlayer insulating film 240. The pixel electrode 111 is formed, for example, by forming ITO on the entire surface of the second interlayer insulating film 240 and etching it with a strongly acidic etching solution such as aqua regia.

  Next, as shown in FIG. 4C, a first partition layer 149 is formed around the pixel electrode 111. The first partition layer 149 is formed, for example, by forming an inorganic insulating material (second insulating film) such as silicon oxide on the second interlayer insulating film 240 and selectively removing the inorganic insulating material on the pixel electrode 111. The The opening (second opening) 149a of the first partition layer 149 is formed to be smaller than the pixel electrode 111 so that the first partition layer 149 partially overlaps with the peripheral portion of the pixel electrode 111 in a planar manner.

  Next, as shown in FIG. 4D, a contact hole penetrating the second interlayer insulating film 240 and the inorganic insulating material 149 is formed on the common electrode wiring 12a. The contact hole includes an opening (first opening) 240 b formed in the second interlayer insulating film 240 and an opening (third opening) 149 b formed in the inorganic insulating material 149. The opening 240b and the opening 149b are simultaneously formed by a common process. Note that the openings 240b and 149b and the opening 149a can be simultaneously formed by a common etching process. In this case, it is necessary to appropriately design the etching conditions. However, if these openings 240b, 149b, and 149a can be formed simultaneously, the manufacturing process can be simplified.

  Next, as shown in FIG. 4E, a second partition layer 150 made of an organic insulating material such as acrylic or polyimide is formed on the first partition layer 149. The height of the second partition layer 150 is set to about 1 to 2 μm, for example, and functions as a partition member for the organic EL element on the substrate 2. When forming the second partition layer 150, it is preferable to form the wall surface of the opening 151 of the second partition layer 150 slightly outward from the opening 149b of the first partition layer 149. As described above, by partially exposing the first partition layer 149 in the opening 151 of the second partition layer 150, the wetting and spreading of the liquid material in the second partition layer 150 can be improved. it can.

Next, as shown in FIG. 5A, the liquid material 114 a containing the hole injection layer forming material is selectively applied to the application position surrounded by the second partition layer 150 by the droplet discharge head 20. The liquid material 114a for forming the hole injection layer includes a hole injection layer forming material and a solvent. In addition, before discharging the liquid material 114a, it is desirable to perform a liquid repellent treatment on the surface of the second partition layer 150 as necessary. As the liquid repellent treatment, a method of treating the surface of the second partition layer 150 with a fluorine-based compound such as CF ₄ , SF ₆ , or CHF ₃ can be employed. By this treatment, the surface of the second partition layer 150 can be made to selectively exhibit non-affinity with respect to the liquid material 114a.

  As the hole injection layer forming material, polyphenylene vinylene whose polymer precursor is polytetrahydrothiophenylphenylene, 1,1-bis- (4-N, N-ditolylaminophenyl) cyclohexane, tris (8-hydroxyquinolinol) Examples thereof include aluminum, polystyrene sulfonic acid, a mixture of polyethylene dioxythiophene and polystyrene sulfonic acid (PEDOT / PSS), and the like. Examples of the solvent include polar solvents such as isopropyl alcohol, N-methylpyrrolidone, and 1,3-dimethyl-imidazolinone.

  Next, as illustrated in FIG. 8B, the solvent of the liquid material 114 a is evaporated by heating, light irradiation, or the like, so that a solid hole injection layer 110 </ b> A is formed on the pixel electrode 111. Subsequently, a liquid material 114b containing a light emitting layer forming material and a solvent is selectively applied onto the hole injection layer 110A in the second partition layer 150 by the same droplet discharge head.

  As the light emitting layer forming material, a known light emitting material capable of emitting fluorescence or phosphorescence can be used. Specifically, (poly) fluorene derivative (PF), (poly) paraphenylene vinylene derivative (PPV), polyphenylene derivative (PP), polyparaphenylene derivative (PPP), polyvinyl carbazole (PVK), polythiophene derivative, polymethyl Polysilanes such as phenylsilane (PMPS) are preferably used. In addition, these polymer materials include polymer materials such as perylene dyes, coumarin dyes, rhodamine dyes, rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, and quinacridone. It can also be used by doping a low molecular weight material such as.

  Next, as shown in FIG. 8C, the solvent of the liquid material 114b is evaporated by heating, light irradiation, etc., and a solid light emitting layer 110B is formed on the hole injection layer 110A. Thus, the functional layer 110 including the hole injection layer 110A and the light emitting layer 110B is formed on the pixel electrode 111.

  Thereafter, the common electrode 12 covering the second partition layer 150, the first partition layer 149, the functional layer 110, and the common electrode wiring 12a is formed on the entire substrate. The common electrode 12 is formed of a material having a standard electrode potential close to that of the common electrode wiring 12a. Specifically, it is formed of any metal selected from Al, Mo, Ti, W, Cr, Ta, and Mg. The common electrode 12 is directly laminated on the common electrode wiring 12 a and is electrically connected to the common electrode wiring 12 a at a portion overlapping the common electrode wiring 12. The common electrode 12 can also be formed by stacking a plurality of layers. In this case, at least the surface in direct contact with the common electrode wiring 12a is formed of the metal.

  When the organic EL element 200 is completed as described above, a protective film is formed on the common electrode 12 as necessary. Then, the surface of the substrate 2 is sealed with a sealing can or a sealing substrate to complete the organic EL device 1.

  As described above, in the method of manufacturing the organic EL device 1 according to the present embodiment, the step of forming the openings 149b and 240b is performed after the patterning of the pixel electrode 111, so that the corrosion of the common electrode wiring 12a is not considered. In addition, the pixel electrode 111 on the common electrode wiring 12a can be removed. Therefore, the degree of freedom in wiring design is increased, and an organic EL device having excellent electrical characteristics and reliability can be provided.

  Moreover, since the opening part 149b and the opening part 240b are simultaneously formed by the same etching process, a manufacturing process can be simplified compared with the case where these are formed separately. In particular, since the opening 149b and the opening 240b are provided in communication within the same plane region, the area of the contact portion can be reduced, which can contribute to the narrowing of the panel.

  Further, since the inorganic insulating material 149 and the second interlayer insulating film 240 are patterned before the functional layer 110 is formed, the functional layer 110 is not damaged by the etching process. For example, this method is particularly effective when the configuration of the pixel electrode 111 is complicated, such as when an optical resonator structure (microcavity structure) is formed inside the organic EL element 200.

[Electronics]
Next, an embodiment of an electronic apparatus provided with the EL device of the present invention will be described with reference to FIG. FIG. 6 is a schematic configuration diagram of an example in which the organic EL device of FIG. 1 which is an example of the EL device of the present invention is applied to a display unit of a mobile phone. A cellular phone 1300 shown in the figure includes the organic EL device of the above embodiment as a small-sized display unit 1301 and includes a plurality of operation buttons 1302, an earpiece 1303, and a mouthpiece 1304. The organic EL device of each of the above embodiments is not limited to the mobile phone, but is an electronic book, a projector, a personal computer, a digital still camera, a television receiver, a viewfinder type or a monitor direct view type video tape recorder, and a car navigation device. , Pagers, electronic notebooks, calculators, word processors, workstations, video phones, POS terminals, devices equipped with touch panels, etc., and can be suitably used as an image display means. An electronic device with excellent characteristics can be provided. Further, the present invention can be applied not only to the display device as described above but also to a light emitting device such as an LED illumination or an LED light source.

1 is an equivalent circuit diagram of an organic EL device which is an embodiment of an EL device of the present invention. It is a plane block diagram of the organic EL device. It is a section lineblock diagram of the organic EL device. It is process drawing explaining the manufacturing method of the organic EL apparatus. It is process drawing explaining the manufacturing method of the organic EL apparatus. It is a schematic block diagram of the mobile telephone which is one Embodiment of the electronic device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Organic EL device (electroluminescence device), 2 ... Substrate, 12 ... Common electrode, 12a ... Common electrode wiring, 104 ... Terminal, 110 ... Functional layer, 110B ... Light emitting layer, 111 ... Pixel electrode, 149 ... First Partition layer (second insulating film), 149a ... opening (second opening), 149b ... opening (third opening), 240 ... second interlayer insulating film (first insulating film), 240b ... opening ( 1st opening), 1300 ... Mobile phone (electronic equipment)

Claims (10)

An electroluminescence device comprising a functional layer composed of at least one layer including a light emitting layer, and a pair of electrodes composed of a pixel electrode and a common electrode sandwiching the functional layer,
A common electrode wiring electrically connected to the common electrode;
An insulating film that insulates the common electrode wiring and the common electrode;
The electroluminescent device, wherein the common electrode and the common electrode wiring are in direct contact with each other through an opening provided in the insulating film.   2. The electroluminescent device according to claim 1, wherein a portion of the common electrode wiring that is in contact with the common electrode is formed of a material having a standard electrode potential closer to the common electrode than the pixel electrode.   The portion of the common electrode that contacts the common electrode wiring is formed of any metal selected from Al, Mo, Ti, W, Cr, Ta, and Mg, and the common electrode wiring The electroluminescent device according to claim 2, wherein the contacting portion is made of any metal selected from Al, Mo, Ti, W, Cr, and Ta. A terminal electrically connected to the pixel electrode or the common electrode is provided on a substrate,
The electroluminescent device according to claim 1, wherein a protective film made of the same material as the pixel electrode is provided on the terminal. A method for manufacturing an electroluminescent device comprising a functional layer comprising at least one layer including a light emitting layer, and a pair of electrodes comprising a pixel electrode and a common electrode sandwiching the functional layer,
Forming a common electrode wiring electrically connected to the common electrode on a substrate;
Forming a first insulating film covering the common electrode wiring on the substrate;
Forming the pixel electrode on the first insulating film;
Forming a first opening reaching the common electrode wiring in the first insulating film;
And a step of forming the common electrode on the surface of the common electrode wiring through the first opening.   6. The method of manufacturing an electroluminescent device according to claim 5, wherein the step of forming the first opening is performed after the pixel electrode is formed and before the functional layer is formed. Forming a partition layer on the first insulating film;
The step of forming the partition layer includes
Forming a second insulating film covering the pixel electrode on the first insulating film;
Forming a second opening reaching the pixel electrode in the second insulating film;
The method of manufacturing an electroluminescent device according to claim 6, further comprising: forming a third opening that communicates with the first opening in the second insulating film.   8. The method of manufacturing an electroluminescent device according to claim 7, wherein the third opening and the first opening are simultaneously formed by a common etching process.   9. The method of manufacturing an electroluminescent device according to claim 8, wherein the first opening, the second opening, and the third opening are simultaneously formed by a common etching process.   An electroluminescent device according to any one of claims 1 to 4 or an electroluminescent device manufactured by the method for manufacturing an electroluminescent device according to any one of claims 5 to 9 is provided. Electronic equipment.

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