JP2007073504A - Element body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an element body mounted with a protecting membrane to appropriately reduce damage toward the element by moisture or the like. <P>SOLUTION: In an organic EL display device P including an organic EL element 100 protected by the protecting membrane a barrier membrane 12, the barrier membrane has an organic membrane 124. The organic membrane 124 is composed of a first organic membrane layer 124a and a second organic membrane layer b. The first organic membrane layer 124a has a smaller contact angle than the second organic membrane layer b has. The second organic membrane layer b is formed in a nearer position toward an organic EL element 100 side than the first organic membrane layer a. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an element body, an inorganic film manufacturing method, and more particularly to an element body including an element protected by a protective film.

  An element body including a protective film and an element protected by the protective film is known. An organic EL display device is an example of such an element body. The organic EL display device includes an organic EL element as an element.

  An organic EL device includes an electrode and an organic solid layer having at least a light emitting layer between the electrodes, and injects electrons and holes from the electrodes on both sides into the light emitting layer in the organic solid layer. It is an element that causes light emission, and can emit light with high brightness. In addition, since it uses light emission of an organic compound, it has characteristics such as a wide selection range of emission colors, and is expected as a light source or an organic EL display device. In particular, an organic EL display device is generally expected as a flat panel display having a wide field of view, high contrast, high-speed response and visibility, thin and light, and low power consumption.

  In general, an organic EL display device includes a pixel composed of an organic EL element including at least an anode, an organic light emitting layer, and a cathode, and an element for lighting and controlling the organic EL element, for example, a transistor. The driving method of the organic EL display device includes a passive matrix method in which organic EL elements arranged in a matrix are driven from the outside by stripe-shaped scanning electrodes and data electrodes (signal electrodes) orthogonal to each other, and a thin film transistor ( Hereinafter, there is an active matrix system that includes a switching element, a driving element, and a memory element, each of which is also referred to as a TFT, and illuminates an organic EL element.

  In general, in the organic EL display device, as the number of pixels increases, the active matrix method in which an organic EL element is driven by a TFT (Thin Film Transistors) is more advantageous than the passive matrix method. This is because the organic EL element of each pixel is lit only during the period when the scan electrode is selected in the passive matrix method, and as the number of pixels increases, the lighting period of the organic EL element becomes shorter and the average luminance tends to decrease. On the other hand, the active matrix method has a switching element and a memory element made of TFT for each pixel, so that the lighting state of the organic EL element is maintained, and operation with high luminance, high efficiency and long life is possible. This is because there is a tendency to be advantageous for high definition and large display. Here, the use of organic TFTs as TFTs may lead to cost reduction and reduction of environmental load. Moreover, since organic TFT can be produced at a low process temperature, it can be produced on a film substrate, and a flexible display is expected to be realized.

  By the way, organic EL elements and organic TFTs are susceptible to erosion due to moisture and oxygen in the air, and in the presence of these elements, degradation such as dark spots or short-circuiting of the elements may occur. In order to prevent such deterioration, it is necessary to provide a means for protecting the element from erosion due to moisture or oxygen in the air. Currently, the entire element is covered with a cover glass or can package in an atmosphere such as dry nitrogen or argon gas. A method of sealing with, for example, is used.

  However, such a sealing method using glass, cans, etc. is expensive to manufacture, and there are cases where there is a limit to thinning the element. Therefore, a structure in which an element such as an organic ELEL element and an organic TFT is covered with a protective film having a moisture-proof function without using glass or a can package has been proposed as shown in Patent Document 1 below.

The protective film for protecting the element from factors that damage the element from the outside such as moisture and oxygen is not limited to the element such as the organic EL element and the organic TFT, and may include an inorganic film as a constituent film. It is normal.
JP 2003-255857 A

  However, the inorganic film may partially have pinholes and may not be dense enough. In this way, a pinhole is partially generated, and moisture may enter the surface of the element from the outside through the pinhole generated in the inorganic film, thereby damaging the element.

  Furthermore, it is conceivable that pinholes generated in the inorganic film are filled by including an organic film in the protective film. In FIG. 1, the protective film 12 according to the background art is composed of an inorganic film 122a / organic film 124 / inorganic film 124b, and an organic EL display device (element) shown by a cross-sectional structure of the substrate 10 / protective film 12 / organic EL element 100 is shown. An enlarged view of the vicinity of the protective film 12 is shown.

  However, since the organic EL display device shown in FIG. 1 is surely covered with the inorganic film 122, the moisture indicated by the arrow a from the substrate side can be shut out by the inorganic film 122a. Some of the moisture indicated by a, which could not be shut out by the inorganic film 122a, and the moisture entering from the side of the organic film as indicated by the arrow b, are indicated by the arrow c. As described above, the organic EL element 00 may be reached through the inorganic film 122b, and the organic EL element 100 may be damaged.

  In addition, such a subject arises even if an element body is not restricted to an organic EL display apparatus, but is another element body.

  The present invention has been made in view of the above problems, and it is a main object of the present invention to provide an element body including a protective film that can more suitably reduce damage to the element due to moisture or the like.

  The invention according to claim 1 is an element body including a protective film and an element protected by the protective film, wherein the protective film includes at least an organic film, and the organic film includes a first organic film layer and a first organic film layer. The first organic film layer has a smaller contact angle than the second organic film layer, and the second organic film layer is closer to the element side than the first organic film layer. It is formed in these.

"Examination of protective film"
The present inventors examined an element body including an organic film in a protective film. As a result, it has been found that an element body having a protective film that can reduce damage to the element due to moisture or the like can be provided by improving the organic film.

  The inventors include two or more organic film layers of the organic film, that is, the first organic film layer and the second organic film layer, and the second organic film layer is closer to the element side than the first organic film layer. We focused on the structure formed at a position close to. As a result of intensive studies, it was surprisingly found that the water can be controlled to move in a certain direction by making the contact angle different between the first organic film layer and the second organic film layer. As a result of further studies on this control, by making the contact angle of the first organic film layer smaller than the contact angle of the second organic film layer, moisture that has penetrated into the organic film layer, particularly the edge of the second organic film layer, is obtained. Moisture that has entered from the portion can be controlled in the direction of movement toward the first organic film layer having a smaller contact angle. Further, it has also been found that when the first organic film layer contains a hydrophilic group such as an OH group, the hydrophilic group traps moisture.

  This will be specifically described with reference to the drawings. In FIG. 2, the protective film 12 is composed of an inorganic film 122a / organic film 124 (first organic film layer 124a, second organic film layer 124b) / inorganic film 122b, and the substrate 10 / protective film 12 / organic EL element 100 is shown. The vicinity of the protective film of the organic EL display device (element body) shown by the cross-sectional structure is shown. The contact angle of the first organic film layer 124a is smaller than the contact angle of the second organic film layer 124b.

  In FIG. 2, the movement direction of moisture that has entered the organic film is controlled as indicated by arrows d, e, and f. The movement of moisture shown for each arrow will be described.

  Arrow d: Moisture present in the first organic film layer 124a (such as moisture a that has entered from a pinhole in the inorganic film 122a) reaches the first organic film layer 124a. Even if moisture tries to enter the second organic film layer 124b from the first organic film layer 124a, due to the difference in contact angle, the first organic film layer 124a side at the boundary surface between the first organic film layer 124a and the second organic film layer 124b. Will be returned.

  Arrow e: For the moisture (arrow e) that has entered from the end (lateral direction) of the second organic film layer 124b, the moving direction from the second organic film layer 124b to the first organic film layer 124a is changed due to the difference in contact angle. Be controlled. Eventually, the first organic film layer 124a is moved over the boundary surface between the first organic film layer 124a and the second organic film layer 124b.

  Arrow f: Moisture in the second organic film layer 124b (such as moisture existing in the second organic film layer 124b in advance) moves from the second organic film layer 124b to the first organic film layer 124a due to a difference in contact angle. Eventually, the boundary between the first organic film layer 124a and the second organic film layer 124b is moved to the first organic film layer 124a.

  In this way, the movement direction of moisture is controlled in a direction far from the organic EL element (on the first organic film layer 124a side) so that moisture that has entered the organic EL element side does not move, so that moisture reaches the organic EL element. Further, it is possible to more suitably prevent the organic EL element from being damaged. Therefore, a more reliable organic EL display device (element body) can be provided.

  In addition, the present inventors have found that the contact angle of the first organic film layer is 40 ° or less, or that the contact angle of the second organic film layer is 100 ° or more (particularly preferably 110 ° or more). It is more suitable for movement control, and when the contact angle of the first organic film layer is 40 ° or less and the contact angle of the second organic film layer is 100 ° or more (particularly preferably 110 ° or more), further moisture movement control is performed. It was also found to be suitable for. The contact angle is defined as “the angle between the liquid surface, the solid surface, and the interior of the liquid where the free surface of the restraining liquid is in contact with the solid wall” as defined in the Physical and Chemical Dictionary (Iwanami Shoten 4th edition).

  The inventors have also found that it is preferable that the first organic film layer comprises at least one of polyvinyl alcohol, cellulose, and starch.

  In addition, the inventors of the present invention preferably include the second organic film layer containing at least one of acrylic resin, epoxy resin, fluorine resin, polystyrene, polyethylene, and polypropylene, and more preferably PTFE ( Polytetrafluoroethylene) and fluorine compounds such as polytrifluoroethylene and polyvinylidene fluoride have been found to be suitable.

  2A and 2B, as another embodiment, the protective film 12 is composed of an inorganic film 122a / organic film 124 (first organic film layer 124a, second organic film layer 124b) / inorganic film 122b as in FIG. The vicinity of the protective film of the organic EL display device (element body) is shown. Similarly, the contact angle of the first organic film layer 124a is smaller than the contact angle of the second organic film layer 124b.

  The structure according to FIG. 2A is shown by the cross-sectional structure of the substrate 10 / the protective film 12 / the organic EL element 100 as in FIG. 2, but the first organic film layer 124a is the second organic film with respect to the organic film 124 of the protective film 12. The layer is covered to the end by the layer 124b. The portion where the first organic film layer 124a is provided has a two-layer structure of the first organic film layer 124a / second organic film layer 124b. The region where the first organic film layer 124a outside from the end is not provided has a single-layer structure of the second organic film layer 124b. Even in the structure in the present embodiment, the moisture moving direction is controlled in the direction far from the organic EL element (first organic film layer 124a side) so that the moisture that has entered the organic EL element side does not move. It is possible to more suitably prevent the organic EL element from being damaged and damaging the organic EL element.

  Further, in the structure according to FIG. 2A, since the end of the first organic film layer 124a is not exposed to the outside air, the air from the outside air to the first organic film layer 124a as indicated by the arrow b in FIG. There will be no ingress of moisture. Accordingly, moisture absorption as an EL element is relatively suppressed, so that the influence of moisture can be further reduced.

  The structure according to FIG. 2B includes a two-layer protective film 12 a and a protective film 12 b as the protective film 12, and is shown by a cross-sectional structure of the protective film 12 b / substrate 10 / protective film 12 a / organic EL element 100. Even in the structure in the present embodiment, the moisture moving direction is controlled in the direction far from the organic EL element (first organic film layer 124a side) so that the moisture that has entered the organic EL element side does not move. It is possible to more suitably prevent the organic EL element from being damaged and damaging the organic EL element. In the structure according to this embodiment, since there are two layers, it can be prevented more suitably in addition to the case of a single layer.

  Note that when a two-layer inorganic film is provided as in the organic EL display device shown in FIGS. 2, 2A, and 2B, moisture is shut out due to the presence of the inorganic film, thereby preventing damage to the element. The inorganic film can be selected as appropriate (one side farther from the element than the first organic film layer or closer to the element than the second organic film layer side) or both (more than the first organic film layer). The side far from the element and the side closer to the element than the second organic film layer side may be omitted. The inorganic film preferably includes at least one of oxide films of SiNx, SiOxNy, SiOx, and Al.

"Organic EL display device"
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, about this embodiment, it is only one form for implementing this invention, and this invention is not limited by this embodiment.

  FIG. 3 is a schematic cross-sectional view of the organic EL display device P according to this embodiment. The organic EL display device P covers the film substrate 10, the barrier film 12 formed on the substrate 10, the organic EL element 100 and the organic TFT 50 formed on the barrier film 12, and the organic TFT 50. And the sealing film 20 that protects the organic TFT 50 from erosion from the outside. Both the barrier film 12 and the sealing film 20 are protective films.

<Board>
The substrate 10 may be formed by appropriately selecting the constituent materials. For example, as the resin, thermoplastic resin, thermosetting resin, polycarbonate, polymethyl methacrylate, polyarylate, polyether sulfone, polysulfone, polyethylene terephthalate polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride, Polystyrene, polyamide, polyimide, polyvinylidene chloride, polyvinyl alcohol, saponified ethylene / vinyl acetate copolymer, fluororesin, chlorinated rubber, ionomer, ethylene / acrylic acid copolymer, ethylene / acrylic acid ester copolymer, etc. A simple substrate can be used. In addition, the substrate may be a glass substrate, a glass-plastic bonded substrate, or a metal plate instead of a resin-based substrate, and the substrate surface may be coated with an alkali barrier film or a gas barrier film. . Further, in the case of a top emission type in which light is emitted from the opposite side to these transparent substrates, the substrate 10 does not necessarily have to be transparent.

<Barrier film>
FIG. 3A shows a cross-sectional view of the barrier film 12 according to the present embodiment. The barrier film 12 uses both an organic film and an inorganic film only in the present embodiment, but may be only an inorganic film. The barrier film 12 is one of protective films.

  The barrier film 12 has a structure of inorganic film 122a / organic film 124 (first organic film layer 124a / second organic film layer 124b) / inorganic film 122b from the substrate 10 side toward the organic EL element 100 side.

  The inorganic film can be appropriately selected and used without any particular limitation. A suitable example of the inorganic film is an inorganic film containing at least one of SiNx, SiOxNy, SiOx, and Al oxide films. The inorganic film can be omitted as necessary. When the two inorganic films 122 such as the inorganic film 122a and the inorganic film 122b are provided as in this embodiment, moisture can be shut out due to the presence of the inorganic film and damage to the element can be prevented. One of the inorganic films (the inorganic film 122a farther to the element than the first organic film layer or the inorganic film 122b closer to the element than the second organic film layer side) or both (the inorganic film 122a and the inorganic film 122b) is omitted. May be.

  Examples of the method for forming the inorganic film include a sputtering method and a CVD method, but are not particularly limited, and an appropriate method may be used. For example, a general thin film forming method such as vacuum deposition, ion plating, sol-gel method, spray method, or CVD can be used.

  The organic film 124 preferably has a configuration in which the contact angle of the first organic film layer 124a is smaller than that of the second organic film layer 124b. In order to reduce the contact angle of the first organic film layer 124a, a hygroscopic agent or the like may be mixed, but from the viewpoint of maintaining smoothness, the hygroscopic agent is not mixed and the first organic film layer 124a and the second organic film It is preferable that the contact angle of the first organic film layer 124a is smaller than that of the second organic film layer 124b using the material of the layer 124b.

  The material of the first organic film layer 124a is not particularly limited and can be appropriately selected and used. For example, an organic film layer containing at least one of polyvinyl alcohol, cellulose, and starch is preferable.

  The contact angle of the first organic film layer 124a is preferably 40 ° or less from the viewpoint of moisture movement control.

  The material of the second organic film layer 124b is not particularly limited and can be appropriately selected and used. For example, the second organic film layer 124b includes at least one of acrylic resin, epoxy resin, fluorine resin, polystyrene, polyethylene, and polypropylene. The organic film layer is suitable, and particularly preferably contains a fluorine compound such as PTFE (polytetrafluoroethylene), polytrifluoroethylene, and polyvinylidene fluoride.

  The contact angle of the second organic film layer 124b is preferably 100 ° or more, particularly preferably 110 ° or more from the viewpoint of moisture movement control.

  The organic film can be formed by plasma polymerization, which is an organic film vapor deposition method that uses a gas containing an organic monomer such as methane or ethylene as a raw material and decomposes it using plasma. A mold resin, a thermosetting resin, or the like can be applied by spin coating or the like, and can be cured after application to form a solid film. However, the present invention is not limited thereto, and an appropriate method can be used as appropriate. it can.

  In order to apply by spin coating or the like, the organic layer material is made of toluene, benzene, chlorobenzene, dichlorobenzene, chloroform, tetralin, xylene, anisole, dichloromethane, γ-butyrolactone, butyl cellosolve, cyclohexane, NMP (N-methyl-2). -Pyrrolidone), dimethyl sulfoxide, cyclohexanone, dioxane or THF (tetrahydrofuran), PGME (propyleneglycol monoethyl ether), PGMEA (propyleneglycol ether ethyl ether), ethyl lactate, DMAc (N.N-dimethyl). , MIBK (methyl isobu yl ketone), IPA (iso propyl alcohol), ethanol, one or more selected from solvents such as water, to dissolve the precursor, a method such as spin coating can be employed. Further, these solvents may not be employed as long as they are solvent-free coatings.

  In the present embodiment, the barrier film 12 is composed of an inorganic film 122a / organic film 124 (first organic film layer 124a / second organic film layer 124b) / inorganic film 122b from the substrate 10 side toward the organic EL element 100 side. Although it consists of composition, it is not restricted to this but can take various composition.

  For example, the structure may be a multi-layer / inorganic film 122b of the inorganic film 122a / organic film 124 (first organic film layer 124a / second organic film layer 124b) from the substrate 10 side toward the organic EL element 100 side. In this case, the movement of moisture is more suitably performed by forming the organic film 124 into a plurality of layers. Alternatively, the inorganic film 122a / organic film 124 (first organic film layer 124a / second organic film layer 124b) and the inorganic film 122b may be formed in a plurality of layers from the substrate 10 side toward the organic EL element 100 side. Since the number of layers of the inorganic film 122b increases in addition to the number of layers of the organic film 124, a moisture barrier effect by the inorganic film can be obtained.

<Organic EL device>
FIG. 4 shows an enlarged view of the vicinity of the organic EL element 100 of the organic EL display device P. The organic EL element 100 is formed by laminating an anode 14 / an organic solid layer 16 / a cathode 18 from the barrier film 12 side.

  The anode 14 may be a layer having an energy level at which holes are easily injected. A transparent electrode such as ITO (Indium tin oxide) can be used, but the organic EL display device is a top emission type. In this case, a general electrode may be used instead of the transparent electrode.

  A transparent conductive material such as ITO is formed to a thickness of, for example, 150 nm by sputtering or the like. Instead of ITO, a zinc oxide (ZnO) film, IZO (indium zinc oxide alloy), gold, copper iodide, or the like may be employed instead.

  The organic solid layer 16 includes a positive hole injection layer 162 / a positive hole transport layer 164 / a light emitting layer 166 / an electron transport layer 167 / an electron injection layer 168 from the anode 14 side.

  The hole injection layer 162 is a layer that is provided between the anode 14 and the hole transport layer 164 and promotes injection of holes from the anode 14. With the hole injection layer 162, the driving voltage of the organic EL element 100 can be lowered. Also, it may play a role such as stabilizing hole injection and extending the life of the element, or covering an uneven surface such as a protrusion formed on the surface of the anode 14 to reduce element defects. is there.

  The material of the hole injection layer 162 may be appropriately selected so that the ionization energy is between the work function of the anode 14 and the ionization energy of the hole transport layer 164. For example, triphenylamine tetramer (TPTE), copper phthalocyanine, and the like can be used.

  The hole transport layer 164 is a layer that is provided between the hole injection layer 162 and the light emitting layer 166 and promotes the transport of holes, and has a function of appropriately transporting holes to the light emitting layer 166.

  The material of the hole transport layer 164 may be appropriately selected so that the ionization energy is between the hole injection layer 162 and the light emitting layer 166. For example, TPD (triphenylamine derivative) and NPB (N, N-di (naphthalene-1-yl) -N, N-diphenyl-benzidine) can be employed.

The light emitting layer 166 is a layer that recombines the transported holes and the transported electrons, which will be described later, to emit fluorescence or phosphorescence. The material of the light-emitting layer 166 may be selected as appropriate so as to satisfy the properties corresponding to the above light-emitting modes. For example, tris (8-quinolinolato) aluminum complex (Alq), bis (benzoquinolinolato) beryllium complex (BeBq), tri (dibenzoylmethyl) phenanthroline europium complex (Eu (DBM) 3 (Phen)), ditoluyl Vinyl biphenyl (DTVBi), poly (p-phenylene vinylene), π-conjugated polymers such as polyalkylthiophene, and the like can be used. For example, an aluminum quinolinol complex (Alq ₃ ) can be used to emit green light.

The electron transport layer 167 is provided between the electron injection layer 168 and the light emitting layer 166 and has a function of transporting electrons to the light emitting layer 166. For the electron-transport layer 167, for example, an aluminum quinolinol complex (Alq ₃ ) or the like can be used.

  The electron injection layer 168 is provided between the electron transport layer 167 and the cathode 18 and has a function of promoting the injection of electrons from the cathode 18.

The material of the electron transport layer 168 may be appropriately selected so as to be between the work function of the cathode 18 and the electron affinity of the light emitting layer 166. For example, the electron transport layer 168 may be a thin film (for example, 0.5 nm) such as LiF (lithium fluoride) or Li ₂ O (lithium oxide).

  Each layer constituting the organic solid layer 16 is usually made of an organic material, and may be made of a high molecular weight organic material when it is made of a low molecular weight organic material. As a method for forming the organic solid layer 16, for example, an organic solid layer made of a low-molecular organic substance is generally dried by a vapor deposition method or the like (vacuum process), and an organic solid layer made of a high-molecular organic substance is generally spin-coated. Each can be formed by a wet process such as blade coating, dipping, spraying, and printing.

  Examples of the organic material used for each layer constituting the organic solid layer 16 include polymer materials such as PEDOT, polyaniline, polyparaphenylene vinylene derivative, polythiophene derivative, polyparaphenylene derivative, polyalkylphenylene, and polyacetylene derivative.

  In the present embodiment, the organic solid layer 16 includes a hole injection layer 162, a hole transport layer 164, a light emitting layer 166, an electron transport layer 167, and an electron injection layer 168. There is no limitation, and the light-emitting layer 166 may be included at least.

  For example, depending on the characteristics of the organic material used, etc., in addition to a single layer structure of the light emitting layer, etc., a two-layer structure such as a hole transport layer / light emitting layer, a light emitting layer / electron transport layer, etc. / A three-layer structure of an electron transport layer, or a multilayer structure including a charge (hole, electron) injection layer and the like.

Further, a hole blocking layer may be provided between the light emitting layer 166 and the electron transport layer 168 in the organic solid layer 16. The holes may pass through the light emitting layer 166 and reach the cathode 18. For example, when Alq ₃ or the like is used for the electron transport layer 168, the holes flow into the electron transport layer, so that the Alq ₃ emits light or the holes cannot be trapped in the light emitting layer, resulting in a decrease in light emission efficiency. there's a possibility that. Therefore, a hole blocking layer may be provided to prevent holes from flowing out from the light emitting layer 166 to the electron transporting layer 168.

  For the cathode 18, a material having a small work function or electron affinity may be selected in order to improve electron injection into the organic solid layer 16. For example, an alloy type (mixed metal) such as an Mg: Ag alloy or an Al: Li alloy can be suitably used. The cathode 18 can be formed of a metal material such as Al, Mg, or Ag by vacuum deposition or the like to a thickness of 150 nm, for example.

<Organic transistor (organic TFT)>
In the present embodiment, the organic EL display device P that is driven using an organic transistor (organic TFT) has been described. However, the present invention is not limited to this, and the driving means can be selected as appropriate. .

  FIG. 5 shows an enlarged view of the vicinity of the organic TFT 50 of the organic EL display device P. The organic TFT 50 includes a gate electrode 52 formed on the barrier film 12 from the barrier film 12 side, and a gate insulating film 54 formed so as to cover the surface of the gate electrode 52.

  On the gate insulating film 54, an organic semiconductor layer 56, a source electrode 58 on the left edge side, and a drain electrode 60 on the right edge side are formed. Here, the drain electrode 60 is electrically connected to the anode 14 of the organic EL element 100. That is, in the organic TFT 50, the source electrode 58 and the drain electrode 60 are provided separately from each other, the organic semiconductor layer 56 is interposed between the source electrode 58 and the drain electrode 60, and the source electrode 58 is interposed via the gate insulating film 54. , A drain electrode 60, and a gate electrode 52 disposed to face the organic semiconductor layer 56.

  The gate electrode 52 may be any metal that can be anodized as a gate electrode material, and a single substance such as Al, Mg, Ti, Nb, Zr, or an alloy thereof may be used, but is not limited thereto. The gate electrode only needs to have sufficient conductivity. For example, Pt, Au, W, Ru, Ir, Al, Sc, Ti, V, Mn, Fe, Co, Ni, Zn, Ga, Y, Zr, Nb, Mo, Tc, Rh, Pd, Ag, Cd, Ln, Sn, Ta, Re, Os, Tl, Pb, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, A single metal such as Er, Tm, Yb, or Lu, or a laminate or a compound thereof may be used. In addition, organic conductive materials including conjugated polymer compounds such as metal oxides such as ITO and IZO, polyanilines, polythiophenes, and polypyrroles may be used.

  The manufacturing method of the gate electrode 52 may be a general method for forming the wiring pattern of the gate electrode 52 on the substrate 10. A sputtering method, a CVD method, and the like can be given, but there is no particular limitation, and an appropriate method may be used. For example, general thin film forming methods such as vacuum deposition, ion plating, sol-gel method, spin coating method, spray method, and CVD are also possible.

The gate insulating film 54 may be preferably formed as the gate insulating film 54 by anodizing the surface of the material used as the material of the gate electrode 52. However, the present invention is not limited to this, and any insulating material such as an inorganic material or an organic material can be used. Further, not limited to metal oxides, sulfides such as FeS, Al ₂ S ₃ , MgS, ZnS, fluorides such as LiF, MgF ₂ , SmF ₃ , chlorides such as HgCl, FeCl ₂ , CrCl ₃ , AgBr, CuBr, MnBr bromides such as _2, PbI _{2, CuI,} not particularly limited and may be a metal oxynitride such as iodide or SiAlON, such FeI _2. Moreover, it is not restricted to a metal or a metal compound, You may use organic materials, such as polymer materials, such as a polyimide, polyamide, polyester, polyacrylate, an epoxy resin, a phenol resin, and polyvinyl alcohol.

  The method for forming the gate insulating film 54 is not particularly limited, and an appropriate method may be used. For example, a sputtering method, a CVD method, and the like can be mentioned, but a general thin film forming method such as vacuum deposition, ion plating, sol-gel method, spin coating method, spray method, and CVD can also be used. As long as it is an organic film, it may be formed by a spin coating method, a printing method, a vapor deposition method, or the like.

  The source electrode 58 and / or the drain electrode 60 are applicable as long as they have sufficient conductivity, and are not particularly limited. For example, Pt, Au, W, Ru, Ir, Al, Sc, Ti, V, Mn, Fe, Co, Ni, Zn, Ga, Y, Zr, Nb, Mo, Tc, Rh, Pd, Ag, Cd, Ln, Sn, Ta, Re, Os, Tl, Pb, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, etc. Metal simple substance or laminate or compound thereof, Metal oxide such as ITO, IZO, Polyaniline, Polythiophene And organic conductive materials containing conjugated polymer compounds such as polypyrroles can be used.

  The source electrode 58 and the drain electrode 60 may be manufactured by a general method. A sputtering method, a CVD method, and the like can be given, but there is no particular limitation, and an appropriate method may be used. For example, a general thin film forming method such as vacuum deposition, ion plating, sol-gel method, spray method, spin coating method, CVD, lift-off, or the like is also possible.

  The organic semiconductor 56 may be any organic material that exhibits semiconductor characteristics, such as pentacene, and is not particularly limited. For example, phthalocyanine derivatives, naphthalocyanine derivatives, azo compound derivatives, perylene derivatives, indigo derivatives, quinacridone compounds, and the like. Derivatives, polycyclic quinone derivatives such as anthraquinones, cyanine derivatives, fullerene derivatives, or nitrogen-containing compounds such as indole, carbazole, oxazole, inoxazole, thiazole, imidazole, pyrazole, oxadiazole, pyrazoline, thiathiazole, triazole Cyclic compound derivatives, hydrazine derivatives, triphenylamine derivatives, triphenylmethane derivatives, stilbenes, quinone compound derivatives such as anthraquinone diphenoquinone, anthracene, bilene, fluoro Polycyclic aromatic compound derivatives such as nanthrene and coronene whose structure is used in the main chain of polymer such as polyethylene chain, polysiloxane chain, polyether chain, polyester chain, polyamide chain, polyimide chain, etc. Attached in a pendant form as a chain, or an aromatic conjugated polymer such as polyparaphenylene, an aliphatic conjugated polymer such as polyacetylene, a heterocyclic conjugated polymer having a polypinol or polythiophene ratio, a polyaniline, Hetero-atom conjugated polymers such as polyphenylene sulfide, composite type having a structure in which structural units of conjugated polymers such as poly (phenylene vinylene), poly (annelen vinylene) and poly (chenylene vinylene) are alternately bonded Carbon-based conjugated polymers such as conjugated polymers are used. Also, oligosilanes such as polysilanes, disilanylene allylene polymers, (disilanylene) ethenylene polymers, and disilanylene carbon-based conjugated polymer structures such as (disilanylene) ethynylene polymers alternate with carbon-based conjugated structures. Polymers linked to are used. In addition, polymer chains made of inorganic elements such as phosphorus and nitrogen may be used, and polymers having aromatic chain ligands such as phthalocyanate polysiloxane coordinated, perylenetetracarboxylic Polymers in which perylenes such as acids are heat-treated and condensed, ladder-type polymers obtained by heat-treating polyethylene derivatives having a cyano group such as polyacrylonitrile, and organic compounds intercalated in perovskites The composite material may be used.

  A method for forming the organic semiconductor 56 includes a vapor deposition method and the like, but is not particularly limited, and an appropriate method may be used. For example, a general thin film forming method such as ion plating, a sol-gel method, a spray method, or a spin coating method can be used.

  In the present embodiment, the organic TFT 50 is used as a drive element of the organic EL element 100, but the present invention is not limited to this, and another transistor can be used. Further, in the case of a passive method, a transistor may not be used.

<Sealing film>
FIG. 3B shows a cross-sectional view of the sealing film 20 according to the present embodiment. The sealing film 20 is one of protective films. The sealing film 20 has a structure of inorganic film 202a / organic film 204 (second organic film layer 204b / first organic film layer 204a) / inorganic film 204b from the organic EL element 100 side toward the outside.

  The inorganic film can be appropriately selected and used without any particular limitation. A suitable example of the inorganic film is an inorganic film containing at least one of SiNx, SiOxNy, SiOx, and Al oxide films. The inorganic film can be omitted as necessary. When the two inorganic films 202 such as the inorganic film 202a and the inorganic film 202b are provided as in this embodiment, moisture can be shut out due to the presence of the inorganic film and damage to the element can be prevented. One of the inorganic films (the inorganic film 202a farther to the element than the first organic film layer or the inorganic film 202b closer to the element than the second organic film layer side) or both (the inorganic film 202a and the inorganic film 202b) is omitted. May be.

  Examples of the method for forming the inorganic film include a sputtering method and a CVD method, but are not particularly limited, and an appropriate method may be used. For example, a general thin film forming method such as vacuum deposition, ion plating, sol-gel method, spray method, or CVD can be used.

  The organic film 204 is preferably configured such that the first organic film layer 204a has a smaller contact angle than the second organic film layer 204b. In order to reduce the contact angle of the first organic film layer 204a, a hygroscopic agent or the like may be mixed, but from the viewpoint of maintaining smoothness, the hygroscopic agent is not mixed and the first organic film layer 204a and the second organic film It is preferable that the contact angle of the first organic film layer 204a is smaller than that of the second organic film layer 204b using the material of the layer 204b.

  The material of the first organic film layer 204a is not particularly limited and can be appropriately selected and used. For example, an organic film layer containing at least one of polyvinyl alcohol, cellulose, and starch is preferable.

  The contact angle of the first organic film layer 204a is preferably 40 ° or less from the viewpoint of moisture movement control.

  The material of the second organic film layer 204b is not particularly limited and can be appropriately selected and used. For example, the second organic film layer 204b includes at least one of acrylic resin, epoxy resin, fluorine resin, polystyrene, polyethylene, and polypropylene. The organic film layer is suitable, and particularly preferably contains a fluorine compound such as PTFE (polytetrafluoroethylene), polytrifluoroethylene, and polyvinylidene fluoride.

  The contact angle of the second organic film layer 204b is preferably 100 ° or more, particularly preferably 110 ° or more from the viewpoint of moisture movement control.

  The organic film can be formed by plasma polymerization, which is an organic film vapor deposition method that uses a gas containing an organic monomer such as methane or ethylene as a raw material and decomposes it using plasma. A mold resin, a thermosetting resin, or the like can be applied by spin coating or the like, and can be cured after application to form a solid film. However, the present invention is not limited thereto, and an appropriate method can be used as appropriate. it can.

  In order to apply by spin coating or the like, the organic layer material is made of toluene, benzene, chlorobenzene, dichlorobenzene, chloroform, tetralin, xylene, anisole, dichloromethane, γ-butyrolactone, butyl cellosolve, cyclohexane, NMP (N-methyl-2). -Pyrrolidone), dimethyl sulfoxide, cyclohexanone, dioxane or THF (tetrahydrofuran), PGME (propyleneglycol monoethyl ether), PGMEA (propyleneglycol ether ethyl ether), ethyl lactate, DMAc (N.N-dimethyl). , MIBK (methyl isobu yl ketone), IPA (iso propyl alcohol), 1 or more kinds selected from a solvent such as ethanol, to dissolve the precursor, a method such as spin coating can be employed. Further, these solvents may not be employed as long as they are solvent-free coatings.

  In the present embodiment, the structure of the sealing film 20 is the structure of the inorganic film 202a / organic film 204 (second organic film layer 204b / first organic film layer 204a) / inorganic film 202b from the organic EL element 100 side toward the outside. However, the present invention is not limited to this, and various configurations are possible.

  For example, the structure may be a multi-layer / inorganic film 202b of the inorganic film 202a / organic film 204 (second organic film layer 204b / first organic film layer 204a) from the organic EL element 100 side toward the outside. In this case, the movement control of moisture is more suitably performed by forming the organic film 204 into a plurality of layers. Moreover, it is good also as a structure which makes the inorganic film 202a / organic film 204 (2nd organic film layer 204b / first organic film layer 204a) and the inorganic film 202b into multiple layers toward the outer side from the organic EL element 100 side. Since the number of layers of the inorganic film 202b increases in addition to the number of layers of the organic film 204, a moisture barrier effect by the inorganic film can be obtained.

  In the present embodiment, the barrier film 12 and the sealing film 20 are not only used as a protective film for protecting the organic EL element 100 from moisture yesterday, but also filled with pinholes and surface irregularities in which the organic film is formed on the inorganic film, Flatten the surface. Also, it may play a role of relaxing the film stress of the inorganic film.

  The manufacturing method of each layer of the organic EL element 100 and the organic TFT 50 in the organic EL display device P includes, for example, gravure coating, gravure reverse coating, comma coating, die coating, lip coating, cast coating, roll coating, and air knife as printing methods. Coat, Mayer bar coat, Extruded coat, Offset, UV curable offset, Flexo, Stencil, Silk, Curtain flow coat, Wire bar coat, Reverse coat, Gravure coat, Kiss coat, Blade coat, Smooth coat, Spray coat, Overflow coat, Various printing methods such as brushing can be applied. In addition to coating the lower layer as a dry film, the lower layer and the upper layer can be dried in two layers in a wet state.

<Light emission mode of organic EL display device>
The light emission mode of the organic EL display device P will be described.

  When a voltage is applied between the gate electrode 52 and the source electrode 58, holes are generated at the interface (region of about several nm) between the organic semiconductor 56 and the gate insulating film 54. When a voltage is applied between the source electrode 58 and the drain electrode 60 after the holes are generated, the holes can be transported. On the other hand, holes are not transported unless a voltage is applied between the gate electrode 52 and the source electrode 58. Thus, switching can be performed using the non-conducting state (the switch is off) and the conducting state (the switch is on).

  Holes (holes) are supplied from the source electrode 58 to the drain electrode 60 through the gate insulating film 54. Holes are transmitted to the anode 14 of the organic EL element 100 through the drain electrode 60.

  In the organic EL element 100, holes are transported from the anode 14 to the hole injection layer 162 in the organic solid layer 16. The transported holes are injected into the hole transport layer 164. The holes injected into the hole transport layer 164 are transported to the light emitting layer 166.

  In the organic EL element 100, electrons are transported from the cathode 18 to the electron injection 168 in the organic solid layer 16. The transported electrons are injected into the electron transport layer 167. The transported electrons are transported to the light emitting layer 166.

  The transported holes and electrons recombine in the light emitting layer 166. During recombination, light emitted by EL is generated by the energy emitted. This light emission is led out to the outside through the hole transport layer 164, the hole injection layer 162, the anode 14, the barrier film 12, and the substrate 10 in order, and the light emission can be visually recognized.

  When Al is used for the cathode 18, the interface between the cathode layer 18 and the electron transport layer 168 becomes a reflection surface, and is reflected at this interface, proceeds to the anode 14 side, passes through the substrate 10, and goes to the outside. Is injected. Therefore, when the organic EL element having the above configuration is employed in a display or the like, the substrate 10 side becomes the display observation surface.

  For example, when a full color display is to be realized in an organic EL display device, for example, a method of manufacturing organic EL elements that emit RGB colors by painting (coloring method), an organic EL element that emits white light, and a monochromatic light emitting device. A method combining a color filter (color filter method), a method combining a single color light emitting organic EL element such as blue light emission or white light emission and a color conversion layer (color conversion method), a single color organic EL element, and organic A method for realizing a plurality of light emission by irradiating the light emitting layer with electromagnetic waves (photo bleaching method) or the like is exemplified, but it is not particularly limited.

  In the organic EL display device (element body) of this embodiment, it is possible to control the moisture to move in a certain direction by making the contact angle different between the first organic film layer and the second organic film layer. I found it. As a result of further studies on this control, by making the contact angle of the first organic film layer smaller than the contact angle of the second organic film layer, moisture that has penetrated into the organic film layer, particularly the edge of the second organic film layer, is obtained. Moisture that has entered from the portion can be controlled in the direction of movement toward the first organic film layer having a smaller contact angle. Thereby, the protective film which can reduce the damage to the element by moisture etc. more suitably can be provided. In addition, when the first organic film layer includes a hydrophilic group such as an OH group, the hydrophilic group traps moisture.

  In the above embodiment, the barrier film 12 has been described for convenience of explanation, but the present invention is not limited to this and can be applied to general protective films. Of course, you may use for the sealing film 20 in the said embodiment, It can use as a protective film of an element body provided with the element general used for an organic solar cell and a display, without being restricted to this. The display as the element body is not limited to the organic EL display device, but may be a semiconductor laser, a display in general, for example, a liquid crystal display, an electrophoretic display, an electronic paper, a toner display, etc. (For example, CNT-FET), diodes, capacitors, general circuit elements such as compound semiconductors, and the like.

  In the above embodiment, the barrier film 12 and the sealing film 20 are used because they are more suitable for protection, but either one of them can be omitted.

It is typical sectional explanatory drawing near the protective film of the organic electroluminescence display in background art. It is typical sectional explanatory drawing near the protective film of the organic electroluminescence display in this embodiment. It is typical sectional explanatory drawing near the protective film of the organic electroluminescence display in this embodiment. It is typical sectional explanatory drawing near the protective film of the organic electroluminescence display in this embodiment. It is typical sectional drawing of the organic electroluminescence display in this embodiment. It is sectional drawing of the protective film in this embodiment. It is sectional drawing of the protective film in this embodiment. It is a typical enlarged view near the organic EL element of the organic EL display device in the present embodiment. It is a typical enlarged view near organic TFT of the organic electroluminescence display in this embodiment.

Explanation of symbols

10 Substrate 12 Barrier film (protective film)
14 Anode 16 Organic Solid Layer 18 Cathode 20 Sealing Film (Protective Film)
50 Organic TFT
100 Organic EL element P Organic EL display device

Claims (8)

An element body including a protective film and an element protected by the protective film,
The protective film comprises at least an organic film,
The organic film includes a first organic film layer and a second organic film layer,
The first organic film layer has a smaller contact angle than the second organic film layer,
The element body in which the second organic film layer is formed at a position closer to the element side than the first organic film layer. The element body according to claim 1,
The protective film is an element body in which an inorganic film is provided on at least one of a side farther from the element than the first organic film layer and a side closer to the element than the second organic film layer side. The element body according to claim 2,
The inorganic film is an element body including at least one of SiNx, SiOxNy, SiOx, and Al oxide films. The element body according to any one of claims 1 to 3,
The first organic film layer is an element body including at least one of polyvinyl alcohol, cellulose, and starch. The element body according to any one of claims 1 to 4,
The element body whose contact angle of said 1st organic film layer is 40 degrees or less. The element body according to any one of claims 1 to 5,
The second organic film layer is an element body including at least one of acrylic resin, epoxy resin, fluorine resin, polystyrene, polyethylene, and polypropylene. The element body according to any one of claims 1 to 6,
The element body whose contact angle of said 2nd organic film layer is 100 degrees or more. The element body according to any one of claims 1 to 7,
An element body in which the element is an organic EL element.

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