JP2011154796A - Manufacturing method of organic el device, and organic el device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of an organic EL device and an organic EL device in which, when vapor depositing is carried out by using a mask, peeling of a part of a composition material adhered on the mask is prevented and thereby a sealing defect or the like are prevented from occurring. <P>SOLUTION: The manufacturing method of an organic EL device provided with an organic EL element having an organic functional layer 40 including at least an organic light emitting layer between a pixel electrode 20 and a counter electrode 60 includes a process for forming a pixel electrode 20 on a substrate 10, a process for forming barrier ribs 34 surrounding the pixel electrode 20, a process for forming an organic functional layer 40 on the pixel electrode 20 and the barrier ribs 34, and a process for forming a counter electrode 60 on the organic functional layer 40. The process for forming the counter electrode 60 has a process for forming a fluorine-containing layer 60b on an opposite side to the organic functional layer 40, on the counter electrode 60. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an organic EL device manufacturing method and an organic EL device.

  In recent years, with the diversification of information equipment and the like, there is an increasing need for flat display devices that consume less power and are lighter. As one of such flat display devices, an organic electroluminescence device (organic EL device) that performs display by emitting light from an organic electroluminescence device (organic EL device) having a functional layer (organic functional layer) including an organic light emitting layer. ) Has been proposed.

  The organic EL device has a so-called top emission method in which light emitted from an organic EL element is extracted from a side opposite to the substrate side on which the element is formed, and is transmitted through the substrate from the side on which the organic EL element is formed. There are two types of display methods, the so-called bottom emission method. Comparing these two types of display methods, the top emission type organic EL device has a structure that is easy to increase the pixel aperture ratio and is advantageous for high definition and high image quality of the display screen.

  Moreover, in an organic EL device, it is necessary to use a light-transmitting electrode as an electrode on the side from which light emitted from the light emitting layer is extracted. Therefore, in the top emission method, the cathode (electrode) on the light extraction side needs to be light transmissive. As such a light-transmitting cathode, a transparent conductive material such as ITO (Indium Tin Oxide) is used, or a metal material (alloy material) such as silver, aluminum, or MgAg is sufficiently formed into a thin film. For this reason, light transmittance is imparted.

  However, the transparent (light transmissive) cathode formed in this way has a high resistance value due to the physical properties (conductivity) of the forming material itself and the reduced cross-sectional area due to the formation of a thin film. Become. Therefore, particularly in the case of a large organic EL display (organic EL device), due to the voltage drop of the cathode that becomes remarkable due to the high resistance value, for example, between the organic EL elements at the outer peripheral portion and the central portion of the display region. As a result, there is a problem in that the luminance varies, and the display quality deteriorates due to display unevenness such as light emission unevenness and luminance unevenness.

  Therefore, an auxiliary electrode (auxiliary wiring) is formed in a state where it is in conduction with the transparent cathode, and the resistance of the cathode is set to the resistance of the entire electrode including the transparent cathode and the auxiliary electrode, thereby substantially reducing the cathode. It has been proposed to realize resistance and eliminate display unevenness.

  By the way, as a formation method of the said functional layer in an organic EL element, wet coating methods (liquid phase method), such as an inkjet method, and a vapor deposition method (vapor phase method) are known. In addition, regardless of the liquid phase method or the gas phase method, in order to prevent a short circuit between the pixel electrodes (anodes) and to ensure insulation between pixels (between organic EL elements), pixel electrodes ( A method of forming a partition wall on a substrate in a state of surrounding an anode) is known. By forming such a partition wall, for example, even when a functional layer is formed on the entire surface by vapor deposition, each pixel can be separated and independent, and the emitted light is emitted to the adjacent pixel side. Thus, it is possible to prevent the desired display performance from being obtained. Further, by forming the auxiliary electrode as a wiring on such a partition wall, it is possible to realize a substantial reduction in resistance of the cathode as described above.

  By the way, when forming an auxiliary electrode as a wiring on a partition, it is usually formed on a transparent cathode by mask vapor deposition of a highly conductive metal material such as Al. At this time, if the auxiliary electrode passes directly above the pixel electrode, and thus passes through the pixel, the light emission from the pixel is partially blocked, and the display performance is impaired. Therefore, when performing mask vapor deposition for forming such an auxiliary electrode, the mask is closely attached to the transparent cathode, and the auxiliary electrode is selectively formed with high accuracy and directly above the partition without being displaced. (For example, refer to Patent Document 1).

JP 2008-223067 A

  However, when the mask is brought into close contact with the transparent cathode, the transparent cathode has a thin thickness of, for example, about 10 to 50 nm. Therefore, the transparent cathode and the organic functional layer that is the lower layer adhere to the mask. When removed, a part of the transparent cathode and the organic functional layer below it may be peeled off from the substrate side. Such peeling is more likely to occur immediately above the partition wall because the mask adheres more directly above the partition wall.

And if the transparent cathode and the organic functional layer are peeled from the substrate side in this way, the peeled portion becomes a stepped shape or a bowl shape, and then the sealing layer is covered by covering the transparent cathode and the auxiliary electrode. When formed, a sealing defect occurs at the peeled portion, and the durability of the organic EL device is lowered.
In addition, since a mask to which a transparent cathode or an organic functional layer is attached cannot be removed unless it is washed, if it is reused as it is without washing, the deposit is re-transferred to the product and causes a defect.

  The present invention has been made in view of the above circumstances, and the object of the present invention is that when vapor deposition is performed using a mask, the constituent material adheres to the mask and a part thereof peels off, thereby causing a sealing defect or the like. An object of the present invention is to provide a method for manufacturing an organic EL device and an organic EL device, which are prevented from being caused.

In order to achieve the above object, an organic EL device manufacturing method according to the present invention includes an organic E device having an organic functional layer including at least an organic light emitting layer between a pixel electrode and a counter electrode. A manufacturing method of
Forming the pixel electrode on a substrate;
Forming a partition wall surrounding the pixel electrode;
Forming the organic functional layer on the pixel electrode and the partition;
Forming the counter electrode on the organic functional layer,
The step of forming the counter electrode includes a step of forming a fluorine-containing layer on the side of the counter electrode opposite to the organic functional layer.

  According to this method of manufacturing an organic EL device, a fluorine-containing layer is formed on the opposite side of the counter electrode from the organic functional layer. For example, when an auxiliary electrode (auxiliary wiring) is formed on the counter electrode by mask vapor deposition. Further, it is possible to prevent the counter electrode and the organic functional layer underneath from adhering to the mask and partly peeling off. That is, since the fluorine-containing layer has low surface energy and low adhesion, forming the fluorine-containing layer on the surface side of the counter electrode sufficiently reduces the adhesion to the mask. The organic functional layer is prevented from adhering to the mask.

Further, in the method of manufacturing the organic EL device, the step of forming the counter electrode includes a step of forming a counter electrode layer made of a counter electrode material, and fluorinating a surface layer portion of the counter electrode layer. And a step of forming the fluorine-containing layer by forming a fluorine-containing layer.
Thus, if the surface layer portion of the counter electrode layer is fluorinated so that the surface layer portion is a fluorine-containing layer, the fluorine-containing layer can be easily formed by a general process such as plasma treatment. Is possible.

In this method of manufacturing an organic EL device, it is preferable to use magnesium and silver as the counter electrode material, and to form the counter electrode layer with a co-evaporated film of magnesium and silver.
Since the co-evaporated film of magnesium and silver is superior in smoothness, flatness and denseness compared to other counterelectrode materials, the formed counterelectrode is also excellent in smoothness, flatness and denseness. Become. Further, the surface can be easily fluorinated by plasma treatment.

Further, in the method of manufacturing the organic EL device, the step of forming the counter electrode includes a step of forming a counter electrode layer made of a counter electrode material, and a fluorine-containing layer made of a fluoropolymer film on the surface of the counter electrode layer. And forming the fluorine-containing layer by forming a layer.
Thus, if a fluorine-containing layer made of a fluoropolymer film is formed on the surface of the counter electrode layer, the surface energy of the fluorine-containing layer becomes smaller and the adhesiveness is sufficiently low. On the other hand, the adhesiveness is sufficiently low, and therefore, it is more reliably prevented that the counter electrode and the organic functional layer below the counter electrode adhere to the mask.

The method for manufacturing an organic EL device may include a step of forming an auxiliary counter electrode on the fluorine-containing layer located immediately above the partition after the step of forming the counter electrode. .
When the auxiliary counter electrode is formed by a vapor deposition method using a mask (mask vapor deposition), the fluorine-containing layer is formed as described above even if the mask is brought into close contact with the counter electrode in order to improve accuracy. Therefore, it is possible to prevent the counter electrode and the organic functional layer below the mask from adhering to the mask and partly peeling off.

The organic EL device of the present invention is an organic EL device comprising an organic E element having an organic functional layer including at least an organic light emitting layer between a pixel electrode and a counter electrode,
The pixel electrode provided on the substrate;
A partition wall surrounding the pixel electrode;
The organic functional layer provided on the pixel electrode and the partition;
The counter electrode provided on the organic functional layer,
The counter electrode has a fluorine-containing layer on the side opposite to the organic functional layer.

  According to this organic EL device, since the counter electrode forms a fluorine-containing layer on the side opposite to the organic functional layer, for example, when the auxiliary electrode (auxiliary wiring) is formed on the counter electrode by mask vapor deposition, the above-mentioned is described. In this way, it is possible to prevent the counter electrode and the organic functional layer below it from adhering to the mask and partly peeling off.

In the organic EL device, the fluorine-containing layer may be formed by fluorination of a surface layer portion of a counter electrode layer made of a counter electrode material.
Since the fluorine-containing layer is formed by fluorination of the surface layer portion of the counter electrode layer, the fluorine-containing layer can be easily formed by a general process such as plasma treatment.

In this organic EL device, the counter electrode layer is preferably formed of a co-evaporated film of magnesium and silver.
Since the co-evaporated film of magnesium and silver is superior in smoothness, flatness and denseness compared to other counterelectrode materials, the formed counterelectrode is also excellent in smoothness, flatness and denseness. Become. Further, the surface can be easily fluorinated by plasma treatment.

In the organic EL device, the fluorine-containing layer may be a fluorine polymer film formed on the surface of the counter electrode layer made of a counter electrode material.
If the fluorine-containing layer is made of a fluorine polymer film formed on the surface of the counter electrode layer made of the counter electrode material, the surface energy of the fluorine-containing layer becomes smaller and the adhesiveness becomes sufficiently low, Adhesion to the mask is sufficiently low.

In the organic EL device, an auxiliary counter electrode may be provided on the fluorine-containing layer located immediately above the partition.
When the auxiliary counter electrode is formed by a vapor deposition method using a mask (mask vapor deposition), the fluorine-containing layer is formed as described above even if the mask is brought into close contact with the counter electrode in order to improve accuracy. Therefore, it is possible to prevent the counter electrode and the underlying organic functional layer from adhering to the mask, and a part of the counter electrode from peeling off.

It is a schematic diagram which shows the wiring structure of the organic electroluminescent apparatus concerning this invention. 1 is a plan view schematically showing a configuration of an organic EL device according to the present invention. It is a principal part enlarged plan view which shows 1st Embodiment of the organic electroluminescent apparatus of this invention. (A) is an AA arrow directional cross-sectional view of FIG. 3, (b) is a BB arrow directional cross-sectional view. (A)-(c) It is principal part side sectional drawing for demonstrating the manufacturing method of this invention. It is a perspective view which shows an example of the electronic device using the organic EL apparatus of this invention.

Hereinafter, an organic electroluminescence device of the present invention (hereinafter referred to as an organic EL device) will be described in detail with reference to the drawings. In each drawing referred to below, the size of each part is appropriately changed and shown in order to make the drawing easy to see.
First, a schematic configuration of the organic EL device according to the present invention will be described with reference to FIGS.

  FIG. 1 is a schematic diagram showing a wiring structure of an organic EL device 1 according to the present invention. This organic EL device 1 is of an active matrix type using thin film transistors (hereinafter referred to as TFTs) as switching elements, and has a plurality of scanning lines 101 and a direction that intersects each scanning line 101 at a substantially right angle. And a plurality of power lines 103 extending in parallel to each signal line 102, and sub-pixels X are formed in the vicinity of each intersection of the scanning line 101 and the signal line 102. Is. In the present invention, an active matrix using a TFT or the like is not essential, and simple matrix driving may be performed using an element substrate for a simple matrix.

A data line driving circuit 104 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102. Further, a scanning line driving circuit 105 including a shift register and a level shifter is connected to the scanning line 101.
Further, each of the sub-pixels X holds a switching TFT 112 to which a scanning signal is supplied to the gate electrode via the scanning line 101 and a pixel signal shared from the signal line 102 via the switching TFT 112. A capacitor 113, a driving TFT 123 to which a pixel signal held by the holding capacitor 113 is supplied to the gate electrode, and driving from the power line 103 when electrically connected to the power line 103 through the driving TFT 123 A pixel electrode (anode) 20 through which current flows and an organic functional layer 40 sandwiched between the pixel electrode 20 and the counter electrode (cathode) 60 are provided.

  Under such a configuration, when the scanning line 101 is driven and the switching TFT 112 is turned on, the organic EL device 1 holds the potential of the signal line 102 at that time in the storage capacitor 113, and the storage capacitor 113. Depending on the state, the on / off state of the driving TFT 123 is determined. Then, current flows from the power supply line 103 to the pixel electrode 20 through the channel of the driving TFT 123, and further current flows to the counter electrode 60 through the functional layer 40. Thereby, the organic light emitting layer which comprises the functional layer 40 light-emits according to the electric current amount which flows through this.

FIG. 2 is a plan view schematically showing the configuration of the organic EL device 1 according to the present invention.
As shown in FIG. 2, the organic EL device 1 includes a substrate 10, and a pixel portion 130 having a rectangular shape in plan view is formed on the substrate 10. The pixel unit 130 is partitioned into an actual display area 140 in which the sub-pixels X are arranged in a matrix and a dummy area 150 arranged around the actual display area 140.

In this embodiment, the organic functional layer 40 included in each sub-pixel X is configured to emit white light. Accordingly, the sub-pixels X emit light of each color of red (R), green (G), and blue (B) by color filters corresponding to R, G, and B.
In the actual display area 140, the sub-pixels X of the same color are arranged in the vertical direction in the figure, and form a so-called stripe arrangement. In the actual pixel area 140, full-color display is enabled by mixing the light emitted from the sub-pixels X arranged in a matrix and having each color of RGB by a color filter.

  Scanning line driving circuits 105 are arranged on both sides of the actual display area 140 in FIG. 2, and these scanning line driving circuits 105 are arranged on the lower layer side of the dummy area 150. Further, an inspection circuit 160 is disposed on the upper side of the actual display area 140 in FIG. 2, and the inspection circuit 160 is disposed on the lower layer side of the dummy area 150. The inspection circuit 160 is a circuit for inspecting the operating state of the organic EL device 100 and includes, for example, inspection information output means (not shown) for outputting the inspection result to the outside, and is displayed during manufacture or at the time of shipment. It is configured to be able to inspect the quality and defects of the apparatus.

Next, the first embodiment of the present invention will be described as a specific configuration example of the organic EL device. 3 is an enlarged plan view of an essential part showing the first embodiment of the organic EL device of the present invention, FIG. 4A is a cross-sectional view taken along line AA in FIG. 3, and FIG. 4B is FIG. It is a BB arrow directional cross-sectional view.
The organic EL device 1 according to the present embodiment has a plurality of sub-pixels X arranged in an oblong shape (track shape) in the vertical and horizontal directions as indicated by a broken line in FIG.

  The planar view shape of these subpixels X corresponds to the planar view shape of the pixel electrode (anode) 20 exposed in the opening of the partition wall 34, and the pixel electrode 20 is independent for each subpixel X in an island shape. Is formed. Therefore, the sub-pixels X are formed independently and function as independent light-emitting elements (organic EL elements).

  In the organic EL device 1, as shown in FIGS. 4A and 4B, the base 13, the pixel electrode 20 formed on the base 13, and the peripheral edge of the pixel electrode 20 are opened. An insulating film 32 that exposes and exposes the pixel electrode 20 in 32 a, the partition wall 34 that is formed on the insulating film 32 and surrounds the pixel electrode 20, and a functional layer that covers the exposed surface of the pixel electrode 20. 40 and a counter electrode 60 formed on the base 13 so as to cover the functional layer 40. In this embodiment, the pixel electrode (anode) 20 exposed in the opening 32a of the insulating film 32, the functional layer 40 disposed immediately above the pixel electrode (anode) 60, and the counter electrode (cathode) 60 covering the functional layer 40 are provided. Thus, the organic EL element 70 is formed. Further, in the organic EL device 1 of the present embodiment, a top emission method is employed in which light emitted from the organic EL element 70 is emitted to the counter electrode 60 side.

  The base 13 includes a substrate 10 and an element layer 11 that is formed on the substrate 10 and includes wiring, driving elements, and the like. Since the top emission method is adopted as the substrate 10 in this embodiment, either a transparent substrate or an opaque substrate can 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. As the transparent substrate, for example, an inorganic substance such as glass, quartz glass, or silicon nitride, or an organic polymer (resin) such as an acrylic resin or a polycarbonate resin can be used. A composite material formed by laminating or mixing the materials can also be used. In the present embodiment, the above-described opaque plastic film is used as the material of the substrate 10.

  The element layer 11 includes various wirings for driving the organic EL device 1, driving elements such as switching TFTs and driving TFTs shown in FIG. 1, and an insulating film made of an inorganic material or an organic material. Yes. Various wirings and driving elements are formed by patterning using a photolithography technique, an etching technique, etc., and the insulating film is formed by a known film forming method such as a vapor deposition method, a CVD method, or a sputtering method. ing.

  On the element layer 11, as shown in FIG. 4A, an electrode 22 connected to a source electrode of a driving TFT (not shown) included in the element layer 11 is formed. Further, a planarizing layer 12 is formed on the element layer 11 so as to cover the electrode 22. The planarization layer 12 is formed in order to eliminate unevenness due to each component formed in the element layer 11 and realize a flat surface suitable for forming an organic EL element. As a material for forming the planarization layer 12, an organic insulating material such as an acrylic resin or an inorganic insulating material is used.

  A contact hole 12a leading to the electrode 22 is formed in the planarizing layer 12, and a pixel electrode 20 is formed in a region on the planarizing layer 12 including the contact hole 12a. Thereby, the electrode 22 and the pixel electrode 20 are electrically connected via the conductive portion in the contact hole 12a.

  The pixel electrode 20 is formed of a material having a high hole injection effect with a work function of 5 eV or more. As such a material, for example, a metal oxide such as ITO (Indium Tin Oxide) is used. In this embodiment, since the top emission method is adopted, the pixel electrode 20 does not need to have translucency. Therefore, in this embodiment, a light reflective metal layer such as Al is formed below the transparent conductive layer made of ITO to form a laminated structure, and the pixel electrode 20 is formed by this laminated structure. Such pixel electrodes 20 are formed into independent island shapes by being patterned by a known deposition method and then patterned.

The insulating film 32 is formed on the planarizing layer 12. As described above, the insulating film 32 partially covers the peripheral portion of the pixel electrode 20 to cover the peripheral portion, and exposes the pixel electrode 20 in the opening 32a. Here, the opening 32a is formed in an oval shape (track shape) in plan view, as indicated by a broken line in FIG.
The insulating film 32 is formed of an inorganic insulating material such as silicon oxide (SiO ₂ ), silicon nitride (SiN), or silicon oxynitride (SiON), and is sufficiently thinner than the partition wall 34. The opening 32a is formed by a known patterning method such as etching. Therefore, almost no step is formed between the upper surface of the insulating film 32 and the upper surface of the pixel electrode 20 exposed in the opening 32a. Therefore, the upper surface of the insulating film 32 and the upper surface of the pixel electrode 20 are almost the same. A flat surface is formed.

  A partition wall 34 is formed on the insulating film 32 as shown in FIG. The partition wall 34 is formed so as to cover almost the entire surface of the insulating film 32 only by exposing a part of the insulating film 32 riding on the peripheral edge of the pixel electrode 20, and the opening 34a communicating with the opening 32a. Is formed. Therefore, the pixel electrode 20 is exposed in the opening 34a. The partition 34 is formed of an organic material such as acrylic resin, and is formed by a known patterning method.

  The organic functional layer 40 is formed on the pixel electrode 20 and the partition wall 34 in the opening 34a so as to cover them. In this embodiment, the organic functional layer 40 is formed including an organic light emitting layer made of a low molecular weight organic EL material. As such an organic functional layer 40, for example, a structure in which a hole injection layer, a hole transport layer, an organic light emitting layer, an electron transport layer, and an electron injection layer are sequentially stacked from the anode (pixel electrode 20) side is known. In addition, a structure in which the hole transport layer and the electron transport layer are omitted, a hole injection / transport layer having both functions of the hole injection layer and the hole transport layer, or an electron injection layer and an electron transport are used. A structure using an electron injection / transport layer having both functions of a layer is known. In the present invention, an appropriate structure is selected and formed from such structures.

Moreover, as a material of the organic functional layer 40, a well-known thing can each be used.
For example, as the material for the organic light emitting layer, in the present embodiment, a styrylamine light emitting material, a styrylamine light emitting material, or the like is used as an organic light emitting material that emits white light.
Furthermore, as the material for the hole injection layer, triarylamine (ATP) multimers are used, and as the material for the hole transport layer, TDP (triphenyldiamine) -based materials are used. Aluminum quinolinol (Alq3) or the like is used as the material for the transport layer.

  A counter electrode (cathode) 60 is formed on the organic functional layer 40 so as to cover the organic functional layer 40. The counter electrode 60 is a top emission type in the present embodiment, and is formed so as to have light transmittance since it is on the light extraction side. In this embodiment, magnesium (Mg) and silver (Ag) are formed to a thickness of about 12 nm by a co-evaporation method so that the film thickness ratio is Mg: Ag = 10: 1. Such a co-deposited film of Mg and Ag is superior in smoothness, flatness, and denseness compared to other counterelectrode materials, so that the formed counterelectrode 60 has smoothness, flatness, and denseness. It has become an excellent one.

  The counter electrode 60 includes a counter electrode layer 60a made of a co-deposited film of MgAg in this embodiment, and a fluorine-containing layer 60b formed on the opposite side of the counter electrode layer 60a to the organic functional layer 40. It is made up of. As will be described later, the fluorine-containing layer 60b is formed by fluorinating the surface layer portion of the counter electrode layer 60a, and has a thickness of 10 nm or less, for example, about 2 to 5 nm. By being fluorinated in this way, the fluorine-containing layer 60b has low surface energy and low adhesion. Further, since the thickness is 10 nm or less, conduction between the counter electrode 60 (counter electrode layer 60a) and the auxiliary wiring (auxiliary counter electrode) formed thereon is ensured, and formation of a contact hole is achieved. It becomes unnecessary.

  An auxiliary wiring (auxiliary counter electrode) 50 is formed on the fluorine-containing layer 60b of the counter electrode 60 as shown in FIGS. 3 and 4B. The auxiliary wiring 50 is formed on the partition wall 34 along the direction orthogonal to the long side of the subpixel X (the length direction of the short side of the subpixel X), and is a material having higher conductivity than the counter electrode 60. It is formed by. Specifically, a low-resistance metal material such as gold, silver, copper, aluminum, or chromium is used as the highly conductive material.

In this embodiment, it is selectively formed of Al by a vapor deposition method using a mask (mask vapor deposition method). That is, on the partition wall 34, the stripes are formed in a direction orthogonal to the long side of the sub-pixel X. The auxiliary wiring 50 is formed to be sufficiently thick, for example, about 200 nm compared to the thickness of the counter electrode 60.
The counter electrode 60 is connected to a cathode contact portion connected to a cathode extraction terminal (not shown). The auxiliary wiring 50 may also be connected to the cathode contact portion.

  Based on such a configuration, the organic EL element 70 including the pixel electrode 20, the functional layer 40, and the counter electrode 60 is formed. That is, when a voltage is applied between the pixel electrode 20 and the counter electrode 60, holes are injected from the pixel electrode 20 into the hole injection layer and transported to the organic light emitting layer through the hole transport layer. Further, electrons are injected from the counter electrode 60 into the electron injection layer and transported to the organic light emitting layer through the electron transport layer. Then, the holes and electrons transported to the organic light emitting layer are recombined, so that the organic light emitting layer emits light.

  The light emitted from the organic light emitting layer to the pixel electrode 20 side is transmitted through the transparent conductive layer, reflected by the light reflective metal layer, and incident again on the organic light emitting layer side. Since the counter electrode 20 functions as a transflective film, light other than a wavelength in a predetermined range is reflected to the light reflective metal layer side and reciprocates between the counter electrode 60 and the light reflective metal layer. In this way, only light having a resonance wavelength corresponding to the optical distance between the counter electrode 60 and the light reflective metal layer is amplified and extracted. In other words, the space between the counter electrode 60 and the light-reflecting metal layer that functions as a resonator can emit light having a high emission luminance and a sharp spectrum. . Here, the optical distance is obtained by the sum of the optical distances of the layers included between the counter electrode 60 and the light-reflecting metal layer, and the optical distance of each layer is determined by the film thickness and the refractive index. Calculated by product.

  Although not shown, a transparent sealing layer is formed on the surface of the counter electrode 60 and the auxiliary wiring 50 so as to cover them and block moisture and oxygen. A transparent adhesive layer is formed on the transparent sealing layer. Transparent sealing substrates, such as glass, are bonded together through the material. In the present embodiment, red (R), green (G), and blue (B) color filters are formed on the sealing substrate. The transparent sealing layer is formed to have a gas barrier layer and a protective layer formed so as to cover the gas barrier layer. The gas barrier layer is made of an inorganic compound such as silicon nitride, silicon oxynitride, or silicon oxide, and the protective layer is a flexible resin having a low glass transition point, such as urethane, acrylic, epoxy, or polyolefin. It is made of material.

  In manufacturing the organic EL device 1 having such a configuration, in particular, in order to form the organic functional layer 40, the hole injection / transport layer, the organic light emitting layer, and the electron transport / injection layer are formed by a vapor deposition method similar to the conventional one. Sequentially formed. At that time, as shown in FIG. 5A corresponding to the sectional view taken along the line B-B in FIG. 3, the pixel electrode 20 formed in the same manner as the conventional one is covered and the partition wall 34 is also covered and the entire surface is organic. Each forming material of the functional layer 40 is deposited.

In order to form the counter electrode 60, first, a co-deposited film of MgAg is formed by covering the organic functional layer 40 by a co-evaporation method similar to the conventional one, and the counter electrode layer is formed as shown in FIG. 60a is formed. Next, the surface layer portion of the counter electrode layer 60a is fluorinated to form the surface layer portion as a fluorine-containing layer 60b as shown in FIG. As a method for fluorinating the counter electrode layer 60a, plasma treatment using CF ₄ as a gas is preferably employed. Specifically, as such plasma processing, an RIE (reactive ion etching) apparatus is used, the inside of the apparatus is depressurized to about 13 Pa, and the plasma processing is performed with a power of about 0.05 W / cm ² . In addition to CF ₄ , a fluorine-containing gas made of an acyclic compound having no unsaturated bond, such as C ₂ F ₆ or SF ₆ , can be used as the gas for fluorination during the plasma treatment. .

When the plasma treatment is performed in this manner, the counter electrode layer 60a is fluorinated by substituting a fluorine group derived from CF _{4 on the} surface (surface layer portion), and the surface layer portion contains fluorine having a thickness of about 2 to 5 nm, for example. Layer 60b is formed. As described above, the formed fluorine-containing layer 60b has a small surface energy and low adhesion. Note that the surface of the co-deposited film of Mg and Ag is easily fluorinated by plasma treatment as compared with other counter electrode materials to form the fluorine-containing layer 60b.

  Then, in order to form the auxiliary wiring (auxiliary counter electrode) 50 on the counter electrode 60 thus formed, Al is selectively formed using an evaporation mask (not shown) in the same manner as in the prior art. Then, the auxiliary wiring 50 is formed as shown in FIG. At this time, if the auxiliary wiring 50 is directly over the pixel electrode 20 and passes through the sub-pixel X, the light emission from the sub-pixel X is partially blocked, and the display performance is impaired. Therefore, the vapor deposition mask is closely attached to the counter electrode 60, and the auxiliary wiring 50 is selectively formed directly on the partition wall 34 with high accuracy without being displaced.

  When the vapor deposition mask is brought into close contact with the counter electrode 60 in this way, conventionally, the counter electrode and the organic functional layer which is the lower layer adhere to the vapor deposition mask, particularly immediately above the partition wall, and when the vapor deposition mask is removed, The counter electrode and the underlying organic functional layer may peel off from the partition wall 34 (substrate 10 side). However, in the present embodiment, as described above, the surface layer portion of the counter electrode 60 is the fluorine-containing layer 60b having low adhesion, and therefore the fluorine-containing layer 60b is deposited on the fluorine-containing layer 60b even if the deposition mask is adhered to the fluorine-containing layer 60b. Therefore, when the mask is removed, it is possible to prevent the counter electrode 60 and the underlying organic functional layer 40 from being separated from the partition wall 34 (substrate 10 side).

Therefore, in the manufacturing method of the present embodiment, since the fluorine-containing layer 60b having low adhesion is formed on the surface layer portion of the counter electrode 60, the auxiliary wiring (auxiliary counter electrode) 50 is formed on the counter electrode 60 by mask vapor deposition. When the electrode is formed, it is possible to prevent the counter electrode 60 and the organic functional layer 40 underneath from adhering to the vapor deposition mask and partly peeling off.
Furthermore, since the deposited mask to which the counter electrode 60 and the organic functional layer 40 are attached cannot be removed unless it is washed, if it is reused as it is without washing, the deposited matter is re-transferred to the product, causing defects. However, according to the manufacturing method of this embodiment, since the counter electrode 60 and the organic functional layer 40 do not adhere to the vapor deposition mask, it is possible to prevent defects due to retransfer of the deposit on the product. In addition, since the deposition mask does not need to be cleaned, the cost required for cleaning can be reduced.

  Further, in the organic EL device 1 obtained by such a manufacturing method, the counter electrode 60 and the organic functional layer 40 underneath are attached to the vapor deposition mask and a part thereof is peeled off. As a result, when the transparent sealing layer is formed so as to cover the counter electrode 60 and the auxiliary wiring 50, a sealing defect is generated, and the disadvantage that the durability is lowered is prevented.

Next, a second embodiment of the organic EL device of the present invention will be described.
The second embodiment is different from the first embodiment in the configuration of the counter electrode 60 and the manufacturing method thereof.
That is, in the second embodiment, the counter electrode 60 is composed of the counter electrode layer 60a and the fluorine-containing layer 60b, as in the first embodiment, but the fluorine-containing layer 60b is opposite to the previous embodiment. The surface layer portion of the electrode layer 60a is not formed by fluorination, but is made of a fluoropolymer film newly formed on the surface of the counter electrode layer 60a.

  In order to form the fluorine-containing layer 60b made of such a fluoropolymer film, after forming the counter electrode layer 60a as shown in FIG. 5B, a fluoropolymer film is formed on the surface of the counter electrode layer 60a. Then, as shown in FIG. 5C, a fluorine-containing layer 60b made of a fluoropolymer film is formed to a thickness of 10 nm or less, for example, about 2 to 5 nm. If the thickness is 10 nm or less, conduction between the counter electrode 60 (counter electrode layer 60a) and the auxiliary wiring (auxiliary counter electrode) formed thereon can be ensured, formation of a contact hole, etc. Can be made unnecessary.

As a method for forming the fluoropolymer film, a technique of using, for example, CHF ₃ as a gas and subjecting it to plasma polymerization is suitably employed. Specifically, an RIE (reactive ion etching) apparatus is used as such a plasma polymerization process, and the inside of the apparatus is depressurized to about 13 Pa, and the plasma process is performed with a power of about 0.05 W / cm ² . As the fluoropolymer film to be formed, for example - a fluororesin film having a structure of _{[(CF 2 -CF 2) n-} ].

When the plasma polymerization treatment is performed in this manner to form a fluoropolymer film (fluorine-containing layer 60b), the fluorine-containing layer 60b has low surface energy and low adhesion.
Therefore, even in the manufacturing method of the present embodiment, the fluorine-containing layer 60b having low adhesion is formed on the surface of the counter electrode layer 60a. Therefore, auxiliary wiring (auxiliary counter electrode) is formed on the fluorine-containing layer 60b by mask vapor deposition. ) 50 is formed, it is possible to prevent the counter electrode 60 and the organic functional layer 40 underneath from adhering to the vapor deposition mask and peeling off part thereof.
Furthermore, since the counter electrode 60 and the organic functional layer 40 do not adhere to the vapor deposition mask, it is possible to prevent defects due to the retransfer of deposits on the product, and it is not necessary to clean the vapor deposition mask, which is necessary for cleaning. Cost can be reduced.

  Moreover, in the organic EL device obtained by such a manufacturing method, as in the organic EL device 1 of the first embodiment, the counter electrode 60 and the underlying organic functional layer 40 are attached to the vapor deposition mask, Due to part of the peeling, there is a disadvantage that sealing defects are generated when the transparent sealing layer is formed so as to cover the counter electrode 60 and the auxiliary wiring 50 and the durability is lowered. It will be prevented.

(Experimental example)
The organic EL display was each manufactured with the manufacturing method of 1st Embodiment, and the manufacturing method of 2nd Embodiment. For comparison, an organic EL display having a conventional structure that does not include a fluorine-containing layer as a counter electrode was manufactured. These organic EL displays were 8 inches diagonal and 800 × RGB × 480. These organic EL displays were evaluated by emitting light without forming a special sealing structure on the auxiliary wiring.

When these organic EL displays were made to emit light and the number of pixels (sub-pixels) that became a light emission defect was examined, there were several in the first embodiment and the second embodiment, whereas In the comparative example, about 120,000 pieces had light emission defects.
Further, when the number of pixels (sub-pixels) that were stored for 160 hours under the conditions of 85 ° C. and 90% relative humidity and then caused light emission to become a light emission defect was examined, the second embodiment and second In the embodiment, the number of light emitting defects was substantially increased to about 300,000, while in the comparative example, the number was almost unchanged.
Furthermore, when the number of pixels (sub-pixels) that had been stored for 1000 hours under conditions of 85 ° C. and 90% relative humidity and then caused light emission to become a light-emitting defect was examined, the second embodiment and second In the embodiment, the number of light emitting defects was substantially increased to about 800,000, while in the comparative example, the number was almost the same.

From these experimental results, in the conventional one (comparative example), a large amount of initial defects occurred, and after the storage under high temperature and high humidity, the light emitting defects increased further, whereas the first embodiment and the second embodiment It was found that the product had few initial defects, and the state was maintained even after storage under high temperature and high humidity.
In addition, when the organic EL display of the comparative example was observed after the experiment, it was confirmed that almost all of the pixels (sub-pixels) having the light emission defect had the organic functional layer peeled off on the partition wall.
Moreover, when the counter electrode of the organic EL display of 1st Embodiment and 2nd Embodiment was observed by cross-sectional TEM, respectively, and the EDX analysis was carried out, the fluorine of atomic ratio 3% or more was detected on the surface of the counter electrode.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the first and second embodiments, an organic light emitting layer that emits white light is formed and light of each color of RGB is emitted by a color filter. However, an organic functional layer is also formed on the partition wall. In such a case, the material for forming the organic light emitting layer may be separately coated with materials that emit light of each color of RGB to form three types of organic light emitting layers, and the formation of the color filter may be omitted.

(Electronics)
Next, an electronic apparatus will be described as an application example of the organic EL device of the present invention. FIG. 6 is a perspective view showing an example of an electronic apparatus using the organic EL device of the present invention. A cellular phone 1300 shown in FIG. 6 includes the organic EL device of the present invention as a small-sized display portion 1301 and includes a plurality of operation buttons 1302, a mouthpiece 1303, and a mouthpiece 1304. Thereby, it becomes the outstanding mobile telephone 1300 which comprised the display part comprised by the organic electroluminescent apparatus of this invention.

  The organic EL device of the present invention is not limited to the mobile phone, but 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, a car navigation device, It can be suitably used as an image display means for pagers, electronic notebooks, calculators, word processors, workstations, videophones, POS terminals, devices with touch panels, and the like.

  DESCRIPTION OF SYMBOLS 1 ... Organic EL apparatus, 10 ... Board | substrate, 20 ... Pixel electrode, 34 ... Partition, 40 ... Organic functional layer, 50 ... Auxiliary wiring (auxiliary counter electrode), 60 ... Counter electrode, 60a ... Counter electrode layer, 60b ... Fluorine containing layer

Claims (10)

A method of manufacturing an organic EL device including an organic E element having an organic functional layer including at least an organic light emitting layer between a pixel electrode and a counter electrode,
Forming the pixel electrode on a substrate;
Forming a partition wall surrounding the pixel electrode;
Forming the organic functional layer on the pixel electrode and the partition;
Forming the counter electrode on the organic functional layer,
The step of forming the counter electrode includes a step of forming a fluorine-containing layer on the side of the counter electrode opposite to the organic functional layer.   The step of forming the counter electrode includes the step of forming a counter electrode layer made of a counter electrode material, and fluorinating the surface layer portion of the counter electrode layer to make the surface layer portion a fluorine-containing layer. The method for producing an organic EL device according to claim 1, further comprising: forming a containing layer.   3. The method of manufacturing an organic EL device according to claim 2, wherein magnesium and silver are used as the counter electrode material, and the counter electrode layer is formed of a co-evaporated film of magnesium and silver.   The step of forming the counter electrode includes a step of forming a counter electrode layer made of a counter electrode material, and a step of forming the fluorine-containing layer by forming a fluorine-containing layer made of a fluoropolymer film on the surface of the counter electrode layer. The method of manufacturing an organic EL device according to claim 1, further comprising: a step of forming.   5. The method according to claim 1, further comprising a step of forming an auxiliary counter electrode on the fluorine-containing layer located immediately above the partition after the step of forming the counter electrode. A method for producing an organic EL device according to one item. An organic EL device including an organic E element having an organic functional layer including at least an organic light emitting layer between a pixel electrode and a counter electrode,
The pixel electrode provided on the substrate;
A partition wall surrounding the pixel electrode;
The organic functional layer provided on the pixel electrode and the partition;
The counter electrode provided on the organic functional layer,
The organic EL device, wherein the counter electrode has a fluorine-containing layer on a side opposite to the organic functional layer.   The organic EL device according to claim 6, wherein the fluorine-containing layer is formed by fluorination of a surface layer portion of a counter electrode layer made of a counter electrode material.   8. The organic EL device according to claim 7, wherein the counter electrode layer is formed of a co-evaporated film of magnesium and silver.   2. The organic EL device according to claim 1, wherein the fluorine-containing layer is made of a fluoropolymer film formed on the surface of the counter electrode layer made of a counter electrode material.   The organic EL device according to any one of claims 6 to 9, wherein an auxiliary counter electrode is provided on the fluorine-containing layer located immediately above the partition wall.

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