JP3901675B2 - Organic electroluminescence display panel and manufacturing method thereof - Google Patents

Description

  The present invention uses electroluminescence (hereinafter referred to as EL) of an organic compound material that emits light by current injection, and a plurality of organic EL elements each having a light-emitting layer made of a thin film of the organic EL material are arranged in a matrix. The present invention relates to an organic EL display panel.

  In general, micropatterning of the cathode and organic EL medium layer of an organic EL element means that the organic EL medium used for the charge injection layer and the light emitting layer has low heat resistance (generally 100 ° C. or lower), solvent resistance, and moisture resistance. Because it is difficult. For example, when a photolithography method usually used for patterning a thin film is used for an organic EL element, a solvent in the photoresist enters the element, a high-temperature atmosphere in the photoresist baking, an element of a photoresist developer or an etching solution There arises a problem that the characteristics of the organic EL element deteriorate due to intrusion into the substrate or damage due to plasma during dry etching.

  There is also a method of patterning using a vapor deposition mask. However, the organic EL may be caused by wraparound of the vapor deposition due to poor adhesion between the substrate and the mask during vapor deposition, or contact with the mask when the substrate and vapor deposition mask are forcibly adhered. Insufficient mask strength when the media layer is damaged and the anode and cathode made of indium tin oxide (hereinafter referred to as ITO) are short-circuited, or when the aperture is large and the mask is narrow, such as the stripe pattern of the cathode. However, a fine pattern cannot be formed due to problems such as bending of the mask.

  Currently, display panels using organic EL materials are disclosed in JP-A-2-66873, JP-A-5-275172, JP-A-5-258859 and JP-A-5-258860. There is something. This full-color display is a light-emitting device having an image display array composed of a plurality of light-emitting pixels arranged in intersecting rows and columns.

  In this light emitting device, each pixel is disposed on a common electrically insulating light-transmitting substrate. The pixels in each row contain and are joined by a common light transmissive first electrode disposed extending on the substrate. The first electrodes in adjacent rows are spaced laterally on the substrate. The organic EL medium is disposed on a support surface formed by the first electrode and the substrate. Each column of pixels contains and is connected by a commonly extended second electrode disposed on the organic EL medium. The second electrodes in the adjacent rows are arranged at intervals in the lateral direction on the organic EL medium. In this light emitting device, a simple matrix type using a line of first and second electrodes intersecting with an organic EL medium interposed therebetween is adopted.

  A method for solving the above-mentioned problem is disclosed in the above publication. For example, the technique disclosed in Japanese Patent Laid-Open No. 2-66873 is a method in which a photoresist using a solvent that does not dissolve the organic EL medium is patterned on the element, and the cathode is etched using dilute sulfuric acid. However, during etching, the organic EL medium is damaged by dilute sulfuric acid.

  In addition, the techniques disclosed in JP-A-5-275172, JP-A-5-258859, and JP-A-5-258860 have a stripe shape of several to several tens of μm arranged in parallel on a substrate after ITO patterning. In this method, a partition wall having a height is prepared, and an organic EL medium or a cathode material is vapor-deposited on the substrate in a direction perpendicular to the partition wall and in a direction oblique to the substrate surface. That is, a manufacturing method is employed in which the first electrode line and the organic EL medium thin film are selectively formed by oblique vacuum deposition by blocking a predetermined gas flow by a wall having a high boundary provided in advance on the substrate. . However, this method can be patterned only in a direction perpendicular to the oblique deposition direction, and only forms a stripe shape. For this reason, it is impossible to realize a display panel in which RGB are arranged in a delta arrangement or the cathode is bent or meandered.

  In this conventional technique, a high wall perpendicular to the substrate is provided and the high wall is used as a vapor deposition mask, but the aspect ratio (base / height) of the cross section is very large, especially when the pattern is fine. It is difficult to form the wall with a photoresist or the like, and there are many unstable factors in the reliability of the first and second electrode lines and the organic EL medium film after the formation. In addition, there are problems such as the accuracy of oblique vacuum deposition and the complexity of the process.

  The present invention has been made to solve such problems, and an object of the present invention is to provide a display in which the organic EL medium layer and the cathode can be patterned into a free shape without deteriorating the characteristics of the device.

The present invention is an organic EL display panel having an image display array composed of a plurality of light emitting units,
A substrate on which a plurality of first display electrodes corresponding to the light emitting portion are formed;
A plurality of electrically insulating partition walls protruding on the substrate exposing at least a portion of the first display electrode;
A thin film of at least one layer of organic EL medium formed on each of the exposed portions of the first display electrode;
A plurality of second display electrodes formed on a thin film of the organic EL medium,
An overhang portion projecting in a direction parallel to the substrate on the partition;
The second display electrode is not in contact with the partition wall.

In the organic EL display panel, an end portion of the second display electrode may define a light emitting pixel region in the vicinity of the partition wall. Further, in the organic EL display panel may have a first display electrode on or the exposed insulating film formed on at least one edge portion of the first display electrodes under the overhang portion Thereby, a short circuit between the first and second display electrodes can be prevented. Furthermore, in the organic EL display panel, the insulating film may define a light emitting pixel region.

  The organic EL display panel includes an insulating sealing film formed on the first display electrode, the thin film of the organic electroluminescence medium, and the second display electrode, and the insulating sealing film is at least the first The two display electrodes can be completely covered, and thereby the deterioration of the panel can be prevented.

  In the organic EL display panel, the first display electrode and the second display electrode may be a plurality of striped electrodes and arranged at positions orthogonal to each other.

  In the organic EL display panel, the substrate and the first display electrode are transparent, and the second display electrode has a metallic luster, or a reflective film formed on the second display electrode is provided. It is preferable to have.

  Furthermore, in the organic EL display panel according to another embodiment, when the second display electrode is transparent, the first display electrode has a metallic luster or a reflective film formed outside the first display electrode. It is preferable to have.

  According to the present invention, the following effects can be obtained.

  (1) After the organic EL film is formed, it is not necessary to perform a step of damaging the organic EL medium such as patterning. The partition walls can prevent the organic EL medium layer from being damaged and can protect the organic functional layer.

  (2) The number of steps is less than that of the conventional organic EL display panel manufacturing method, the RGB organic layers can be reliably separated, and the RGB medium can be applied with high accuracy.

  (3) The electrode can be patterned into a free shape.

  (4) Since the adjacent second display electrodes can be reliably divided at both side portions of the partition wall, a short circuit between the second display electrodes can be prevented.

  Embodiments according to the present invention will be described below with reference to the drawings.

  As shown in FIG. 1, the organic EL display panel of the embodiment has an image display arrangement that is arranged in a matrix and includes a plurality of light emitting pixels 1 each of which has red R, green G, and blue B light emitting portions. Yes. In addition, a monochrome display panel can be formed by replacing all of the RGB light emitting portions with a single color light emitting portion.

  As shown in FIG. 2, a first display electrode line 3 made of ITO or the like is provided on the substrate 2 of the organic EL display panel. The first display electrode lines 3 are arranged in a plurality of parallel stripes.

  Further, a plurality of electrically insulating partition walls 7 protruding from the substrate 2 are formed over the substrate 2 and the first display electrode line 3 so as to be orthogonal to the first display electrode line 3 as shown in FIGS. Has been. That is, the partition wall 7 is formed so as to expose at least a part of the first display electrode line 3.

  An overhang portion 7 a protruding in a direction parallel to the substrate is formed on the partition wall 7 along the extending direction of the partition wall 7.

  A thin film of at least one layer of the organic EL medium 8 is formed on each exposed portion of the first display electrode line 3. For example, the organic EL medium 8 is a single layer of an organic light emitting layer, or a medium having a three-layer structure of an organic hole transport layer, an organic light emitting layer and an organic electron transport layer, or an organic hole transport layer and a two layer structure of an organic light emitting layer. Media.

  A second display electrode line 9 is formed on the thin film of the organic EL medium 8 along the extending direction. In this manner, the portion of the organic EL medium sandwiched between the first and second display electrode lines corresponds to the light emitting portion.

  A protective film 10 or a protective substrate is preferably provided on the second display electrode 9 of the simple matrix panel. Further, in the organic EL display panel of the above embodiment, the substrate and the first display electrode are transparent, and light emission is emitted from the substrate side. Therefore, as shown in FIG. It is preferable to provide the reflective film 21 above or through a protective film. On the other hand, in the organic EL display panel of another embodiment, the second display electrode can be made of a transparent material, and light emission can be emitted from the second display electrode side. In this case, it is preferable to provide a reflective film outside the first display electrode in order to increase the luminous efficiency.

  Next, an organic EL display panel manufacturing process will be described.

  As shown in FIG. 4, a plurality of conductive transparent films (for example, 0.3 mm pitch, 0.28 mm width, 0.2 μm film thickness) made of ITO or the like are formed in parallel as the first display electrode 3 by the patterning process. A transparent substrate 2 made of glass or the like is prepared.

Next, in the partition wall forming step, a non-photosensitive polyimide 70 as a partition wall material is formed on the first display electrode 3 of the transparent substrate 2 to a film thickness of 3 μm by, for example, a spin coating method, and an overhang portion on the upper portion of the partition wall. The material SiO ₂ 71 is formed on the polyimide film 70 to a thickness of 0.5 μm, for example, by sputtering.

Next, as shown in FIG. 5A, a photoresist is usually formed on the SiO ₂ film 71 by spin coating to a film thickness of, for example, 1 μm, so that a photoregistry 72 having a width of, for example, 20 μm is left. A photoresist pattern is formed using a technique such as photolithography.

Subsequently, as shown in FIG. 5B, the SiO ₂ film 71 is etched into the same pattern shape as that of the photoresist by using reactive ion etching or the like using the photoregistration 72 as a mask. When performing this reactive ion etching, for example, CF ₄ is used as the etching gas, and the etching is completed in 10 minutes at a gas flow rate of 100 sccm and an RF power of 100 W.

Thereafter, as shown in FIG. 5C, by using dry etching or wet etching, the partition wall main body of the polyimide film 70 and the SiO ₂ film 71 of the overhang portion 7a protruding in the direction parallel to the substrate are formed on the partition wall main body. A partition wall 7 having a substantially T-shaped cross section is formed. The height of the T-shaped partition wall 7 from the substrate may be any height as long as the cathode 9 and the ITO anode 3 of the second display electrode to be formed later are not electrically short-circuited. Specifically, it is preferably 1 μm or more and 10 μm or less. For the same reason, it is sufficient that the T-shaped lateral overhang 7a has a width of about 1 μm on one side and a thickness of about 0.2 μm or more.

As shown in FIG. 6A, the T-shaped partition 7 is first subjected to reactive ion etching (anisotropic etching) using a gas such as O ₂ so that the polyimide film 70 is not undercut. Then, as shown in FIG. 6B, the side surface 70a of the polyimide film 70 is isotropically etched by performing wet etching for about 30 seconds with an alkaline solution. In this two-stage etching process, uniform side etching can be performed. FIG. 7A is a cross-sectional view of the T-shaped partition wall 7 prepared by the two-step process.

As another method for etching the polyimide film 70, anisotropic etching is not performed in advance, but isotropic etching is performed for 1 to 2 minutes with an alkaline solution which is a polyimide etchant, using the SiO ₂ film 71 as a mask. The polyimide film 70 can be etched. At this time, since polyimide is etched by wet etching, isotropic etching is performed, and an undercut state is obtained as shown in FIG.

It should be noted that what has been referred to as polyimide so far is a material in a precursor state before imidization, and it goes without saying that it becomes a real polyimide when cured at 300 ° C. in the state of FIG. However, if there are no inconveniences such as strength, the material need not be cured. In addition, as the material instead of polyimide and SiO ₂ , any material can be used as long as it is an insulator that is not etched when the lower partition wall material and the upper overhang material are etched. An electrically insulating material that can maintain strength before film formation can be used.

  Further, instead of such a two-layer structure partition, as shown in FIGS. 7C to 7H, a T-shaped cross section or a reverse tapered cross section (FIG. 7) is obtained by a method such as chlorobenzene treatment of a photoresist. A partition wall having an upper overhang portion such as a partition wall having (c) and (d)) may be formed.

  Thereafter, as shown in FIGS. 8A to 8D, an organic EL medium is deposited on each exposed portion of the first display electrode 3 in the light emitting layer forming step, so that at least one layer of organic EL is deposited. A thin film of the medium is formed, and a second display electrode is formed on the plurality of thin films of the organic EL medium in the next second display electrode forming step. In the figure, only two pixels of RGB three colors are described, but actually, a plurality of pixels are simultaneously formed in two dimensions.

  First, in the light emitting layer forming step, as shown in FIG. 8A, after aligning each one hole 31 of the film formation mask 30 with each one of the recesses of the substrate 2 on which the partition walls 7 are formed, A mask is placed on the partition wall, and the first (for example, red) organic EL medium 8a is formed to a predetermined thickness using a method such as vapor deposition. The substrate may be formed at a free angle with respect to the vapor flow of the organic EL medium, but it is preferable that the vapor flow goes around the overhang portion of the partition wall.

  In the step of FIG. 8B, for example, the film-forming mask is shifted to the left by one partition wall, and then aligned, and then the second organic EL medium 8b (for example, green) is mounted by placing the mask on the partition wall. A film is formed to a predetermined thickness.

  After the film-forming mask is aligned with one concave portion remaining in the process of FIG. 8C, the mask is placed on the partition wall, and the third (for example, blue) organic EL medium 8c is formed to a predetermined thickness. The film is formed. In this manner, the light emitting layer forming step of sequentially moving the mask so that one opening is disposed on one first display electrode and on the adjacent first display electrode is sequentially repeated. Further, since the partition wall 7 is provided, the organic EL medium layer by the mask is not damaged when the deposition mask is aligned or moved and deposited.

  In the second display electrode formation step of FIG. 8D, after forming RGB three types of organic EL media at predetermined locations, the film formation mask is removed, and a method without step coverage (for example, vapor deposition or the like) is used. Vapor is deposited at a predetermined thickness on each of the three types of organic EL media from right above the substrate substantially perpendicularly to form the cathode 9 of the second display electrode. By the vertical incidence of the metal vapor, the cathode 9 is divided at the overhang portion 7a of the partition wall. As a result, the cathodes 9 on both sides of the partition wall are electrically insulated as shown in FIG. Further, the degree to which the metal vapor enters the overhang portion 7a of the partition wall is smaller than the degree of the organic EL medium material particle flow, and the organic EL medium 8 protrudes from the cathode 9 as shown in FIG. A short circuit with the ITO anode 3 is not caused. The thickness of the electrically conductive cathode 9 may be made thick as long as there is no problem. Any material can be used for the cathode as long as it is electrically conductive, but it is a matter of course that a metal having a low resistivity such as Al, Cu, or Au is desirable.

  Next, an organic EL display panel manufacturing method as another embodiment will be described.

  As shown in FIG. 9A, a partition wall 7 having a reverse taper cross section is formed on a substrate 2 on which an ITO anode 3 has been patterned in advance in a predetermined shape. Is formed so as to block the cathode edge portion 9a.

  As shown in FIG. 9B, RGB organic EL media are respectively deposited on the substrate 2 using the deposition mask 30 as described above. Vapor deposition of the organic EL medium is performed by bringing the substrate and the vapor deposition mask into close contact. At this time, since the partition wall serves as a spacer and a gap is formed between the vapor deposition mask and the organic EL medium on the ITO, both come into contact with the organic EL medium. There is no damage. Further, this vapor deposition is performed by rotating the substrate around itself or by using a plurality of evaporation sources from the other direction so as to wrap around the base of the reverse-tapered partition wall. This is for preventing the cathode from protruding from the organic EL medium layer and short-circuiting with the ITO anode when the cathode material is vapor-deposited later.

  Next, as shown in FIG. 9C, a cathode material is deposited from a direction substantially perpendicular to the substrate surface. As shown in the figure, since the overhang portion 7a of the reverse tapered cross-section partition wall blocks the cathode edge portion 9a, the cathode is divided at the upper surface of the partition wall and the root of the partition wall, and the adjacent cathode patterns are electrically insulated.

  Finally, moisture-proof sealing is performed to complete an organic EL full-color display.

  It is clear that a single color display can be achieved by forming an organic EL medium for one color on the entire surface instead of the three-color organic EL medium in the steps of FIGS. 9B and 8A to 8C. is there. If this one color is white and combined with RGB filters, a full color display can be obtained.

  The organic EL display according to the present invention is highly efficient without impairing the original characteristics because there is no wet process after the organic EL medium layer is formed. Further, since the cathode is formed from a substantially vertical direction, an arbitrary cathode pattern can be formed. Further, since the reverse-tapered partition wall is usually made by using a photolithography technique, fine patterning of 10 μm or less is possible.

The feature of the present invention is that there is a partition having an overhang portion in which one or all of the T-shaped cross-section or cross-sectional shape is a reverse taper on the organic EL display substrate, and the base of the reverse taper partition. In other words, the particle flow of the organic EL medium material is more circulated than the particle flow of the cathode metal material.
Example 1
When an organic EL display panel was manufactured using a chemically amplified resist as a partition wall material, a glass substrate patterned with ITO in a stripe shape was sufficiently washed, and a negative photoresist LAX-1 made by Nippon Zeon was spin-coated with 5.6 μm. Next, after pre-baking in a warm air circulation oven, exposure was performed using a striped photomask (cathode gap 20 μm) orthogonal to ITO. Furthermore, in a warm air circulation oven E. After B, development was carried out to form a partition wall having a width of 20 μm and a height of 5.6 μm (see the drawing substitute photo in FIG. 10). While rotating this substrate, TPD was deposited at 700 Å and Alq ₃ was deposited at 550 Å, and then the substrate was stopped and Al was deposited at 1000 Å from a direction perpendicular to the substrate surface (photograph substituted for drawing in FIG. 11). reference). As shown in FIG. 11, the Al film was cut at the upper surface and the root of the partition wall, and the adjacent cathode lines were completely insulated. Furthermore, since the edge of the organic EL medium layer protruded from the edge of Al, no short circuit occurred between Al and ITO.
(Example 2)
When an organic EL display panel is manufactured using a resist treated with C ₆ H ₅ Cl, a glass substrate on which ITO is patterned in a stripe shape is sufficiently washed, spin-coated with a Hoechst positive photoresist AZ6112, and heated in a hot air circulation oven After pre-baking at 30 ° C., it was immersed in a C ₆ H ₅ Cl solution at 32 ° C. for 30 minutes. Next, exposure was performed using a striped photomask (cathode gap: 2 μm) orthogonal to ITO, and development was performed to form a partition wall having a width of 2 μm and a height of 1 μm (see the photo in FIG. 12). . After that, vapor deposition was performed in the same process as in Example 1. As a result, the A1 film was cut off at the upper surface and the base of the partition wall, and the adjacent cathode lines were completely insulated. Furthermore, since the edge of the organic EL medium layer protruded from the edge of Al, a short circuit between A1 and ITO did not occur.

As described above, according to the present invention, electrical insulation between the upper portion of the partition wall and the portion on which the organic EL medium is formed is ensured, and the patterning of the cathode is automatically completed without a photolithography process or the like later. Further, the organic EL medium is formed by matching the partition wall with the mask, so that the organic EL medium is not deteriorated, and the organic EL medium formed on the adjacent pixels does not wrap around because the partition wall exists. It is possible to paint in different areas, and a high-definition full-color display can be realized.
(Example 3)
As another means for realizing a fine pitch display, as shown in FIG. 13, a non-linear element (for example, a thin film transistor (TFT), a capacitor, etc.) connected to the second display electrode is used together with a data signal line and a scanning signal line. There is a full color display formed on the substrate plane. As shown in the figure, a front glass substrate 2 on which an ITO film 3, an organic EL medium layer 8 and a second display electrode 9 are formed is formed in the same manner as in the above embodiment, and a predetermined number of pixels is formed separately from this front substrate. A back glass substrate 102 in which a non-linear element 101 such as a TFT to be connected to the second display electrode is formed is formed, and both substrates are electrically connected only to the second display electrode 9 corresponding to the non-linear element 101. In this way, the anisotropic conductive adhesive 103 is laminated to form a display.

  When a display is manufactured by this method, a cathode independent of each pixel must be formed on the organic EL medium and insulated from the cathodes of other pixels. In order to realize this condition, the above-described T-shaped partition walls can be produced in a two-dimensional matrix.

Furthermore, the present invention solves the problem of dielectric breakdown of the first and second display electrodes and the organic EL layer, and provides a display in which the light emitting functional layer and the second electrode are patterned into a free shape without deteriorating the characteristics of the element. An element that can be produced with a high yield and a method thereof are also provided. That is, as Example 4, a method and an element for adding an insulating film between the first and second display electrodes under the overhang portion of the partition, and as Example 5, an insulating sealing film is added on the partition and the second display electrode. The present invention provides methods and elements.
(Embodiment 4) Addition of insulating film Second display electrode A short circuit between the first and second display electrodes, particularly a short circuit at the edge of the second display electrode is prevented.

  As shown in FIG. 14A, an insulating film 40 is formed at least on a portion corresponding to an edge of a second display electrode pattern to be deposited later on a substrate on which a first display electrode 3 (ITO anode) is patterned in advance in a predetermined shape. Form.

  Next, as shown in FIG. 14 (b), the partition wall 7 having a reverse taper cross-sectional shape is formed on the edge of the second display electrode, ie, the insulating film 40. Form to block. The insulating film 40 is formed in a portion corresponding to the gap of the second display electrode pattern.

  Next, as shown in FIG. 14C, RGB organic materials are vapor-deposited on the substrate 2 using the vapor deposition mask 30 in the same manner as described above. Using the vapor deposition mask 30, R, G, and B organic EL media are vapor-deposited on the substrate. Vapor deposition of the organic EL medium is performed by bringing the substrate and the vapor deposition mask into close contact. At this time, the partition 7 serves as a spacer, and a gap is formed between the vapor deposition mask and the organic EL medium on the first display electrode. The organic EL medium is not damaged.

  Next, as shown in FIG. 14D, a second display electrode material is further deposited on the entire surface so as to cover at least the display region of the substrate. The second display electrode material is deposited at an angle θ (θ <θ ′) that is smaller than the taper angle θ ′ of the inversely tapered partition wall from the normal line from the substrate. For example, as shown in the figure, the cathode material is deposited from a direction substantially perpendicular to the substrate surface. Since the cross section of the partition wall has an inverse taper shape, that is, an overhang portion, the second display electrode is divided at the upper surface of the partition wall and the base of the partition wall, and the adjacent second display electrode patterns are electrically insulated. Even if the edge of the second display electrode overlaps the edge of the organic film, both the second display electrode and the first display electrode are insulated by the insulating film 7 formed in the step of FIG. Does not short circuit.

  Finally, sealing for moisture prevention is performed to complete an organic EL full color display.

  It is apparent that a single color display can be obtained by depositing a material for one color instead of three colors in the process of FIG. If this one color is made white and combined with RGB filters, a full color display is obtained.

  The formation range of the insulating film formed in the process of FIG. 14A is at least the edge portion of the second display electrode divided by the partition walls and the entire surface of the substrate excluding the display dots (segments) at the maximum. For example, in the plan view of the substrate in this insulating film forming step, the insulating film is a pair of parallel insulating film stripes 40a and 40b extending perpendicularly to the first display electrode 3, as shown in FIG. As shown in FIG. 16, it is formed so as to sandwich the root of the partition wall 7 to be formed later. In addition, as shown in FIG. 17, the insulating film may be formed into a stripe in which the pair of stripes shown in FIG. 15 are combined into one, and the partition wall 7 can extend on the center line as shown in FIG. it can. Furthermore, as shown in FIG. 19, the insulating film is connected in the first display electrode extending direction so as to cover the entire surface excluding the pixel, that is, the exposed portion 50 of the first display electrode, and the edge 60 of the first display electrode. If formed in this manner, short-circuiting between the first display electrode edge and the second display electrode can be prevented.

  The organic EL display according to the present invention has high efficiency without impairing the original characteristics because there is no wet process after the light emitting functional layer is formed, and has a degree of freedom in the vapor deposition direction of the second display electrode. Two display electrode pattern shapes are possible. In addition, since an insulating film is inserted between the second display electrode edge portion and the first display electrode, no short circuit occurs in this portion. Furthermore, since the insulating film and the reverse-tapered partition wall are usually formed using a photolithography technique, fine patterning of 10 μm or less is possible.

  Specifically, an organic EL display was fabricated by inserting a process for forming an insulating film between the first display electrode and the partition forming process similar to that in Example 1 above.

  For example, a glass substrate on which ITO is patterned in a stripe shape as a first display electrode is sufficiently washed, and a photoresist OFPR-8000 manufactured by Tokyo Ohka Kogyo Co., Ltd. as an insulating film is pre-baked in a hot air circulation oven, about 1 μm, and ITO. After exposure, development and rinsing using an orthogonal stripe photomask (line width 20 μm), post-baking was performed in a hot air circulation oven. A stripe insulating film 40 shown in FIG. 17 was formed. Next, a negative photoresist LAX-1 made by Nippon Zeon Co., Ltd. is spin-coated with 5.6 μm, pre-baked in a hot air circulating oven, and then the stripe shape so that the center line matches the pattern of the insulating film formed earlier. Exposure was performed using a photomask (line width 18 μm). Furthermore, in a warm air circulation oven E. After B, development was performed to form a reverse-tapered partition wall having a width of 20 μm and a height of 5.6 μm. The taper angle θ ′ of the reverse tapered partition wall was measured and found to be about 30 degrees.

Next, the positional relationship as shown in FIG. 20, that is, the substrate 2 is attached to the turntable in the vacuum processing chamber of the vapor deposition apparatus, the chamber is evacuated to -5 × 10 ⁻⁶ torr, and the first display electrode formation surface of the substrate While rotating so as to rotate with respect to one normal line, TPD as a light emitting functional layer with a thickness of 700 mm, Alq ₃ as a film thickness of 550 mm, and Al as a second display electrode with a thickness of 1000 mm by resistance heating. Vapor deposited. The evaporation source 55 of various materials is arranged on the rotation center line of the substrate 2, and the vapor deposition is performed at an angle θ = 20 degrees between the cone bus line from the evaporation source to the edge of the rotation substrate and the substrate normal, and the inverse taper partition wall is formed. The taper angle θ ′ was performed at an angle smaller than 30 degrees. When the completed element was examined for continuity between adjacent Al lines, it was completely insulated. Further, when a voltage of 10 V was applied between ITO and Al of this element, the selected part emitted bright green light and no short circuit occurred between ITO and Al.
To increase the additional sealing effect of (Example 5) sealing the insulating film of the additional fourth embodiment of causes wrap on the back side of the reverse taper partition wall sealing film, completely covers the second display electrode pattern. Similarly to Example 4, an insulating sealing film 45 having a high moisture-proof effect is deposited on the substrate on which the second display electrode is formed in the steps shown in FIGS. Then, the film is formed by a method with good wraparound such as CVD.

  As shown in FIG. 21, the sealing film wraps around and adheres to the back side of the reverse tapered partition wall 7, so that it reaches the insulating film 40 and completely covers the second display electrode line 9 as shown in FIG. It becomes a covering shape. Further, as shown in FIG. 23, the sealing film 45 may have any shape as long as it completely covers the second display electrode line so as to cover the reverse tapered side wall of the insulating film 40.

  Further, this sealing structure can also be applied to the case of the above-described embodiment without the insulating film of Embodiment 4, and the first sealing film material is made to wrap around the reverse taper partition wall 7 as shown in FIG. The second display electrode line 9 can be completely covered by adhering to the display electrode and the substrate or covering the reverse tapered side wall as shown in FIG.

  The organic EL display according to the present invention has the same effect as that of the fourth embodiment, and the sealing film completely covers the second display electrode pattern, thereby preventing the non-light emitting portion from proceeding from the second display electrode edge. That is, the durability is very high.

  Specifically, an organic EL display was produced by adding a sealing film after the second display electrode forming step of Example 4 above.

In the same process as in Example 4, Al was vapor-deposited to produce an element, and a SiO ₂ film having a thickness of 1 μm was further formed by sputtering. As a result of examining the conduction between adjacent Al lines for the device thus fabricated, it was completely insulated. Further, when a voltage of 10 V was applied between ITO and Al of this element, the selected part emitted bright green light and no short circuit occurred between ITO and Al. Furthermore, when this element was left in the atmosphere, the expansion of the non-light emitting portion from the Al edge was suppressed.

1 is a schematic partially enlarged plan view of an organic EL display panel according to the present invention. 1 is a schematic partial perspective view of an organic EL display panel according to the present invention. 1 is a schematic partial cross-sectional view of an organic EL display panel according to the present invention. The schematic perspective view of the board | substrate of the organic electroluminescence display panel of the Example by this invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of the Example by this invention. The general | schematic partial expanded sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of the Example by this invention. 1 is a schematic partial enlarged cross-sectional view of a partition wall in an organic EL display panel according to an embodiment of the present invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of the Example by this invention. The schematic fragmentary sectional view of the board | substrate in the organic EL display panel manufacturing process of the other Example by this invention. The drawing substitute microscope (SEM) photograph which image | photographed the partition in the organic electroluminescent display panel of Example 1 by this invention. The drawing substitute microscope (SEM) photograph which image | photographed the partition vicinity in the organic electroluminescent display panel of Example 1 by this invention. The drawing substitute microscope (SEM) photograph which image | photographed the partition in the organic electroluminescent display panel of Example 2 by this invention. FIG. 6 is a schematic partial cross-sectional view of an organic EL display panel according to Example 3 of the present invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of Example 4 by this invention. The schematic partial top view of the board | substrate in the organic EL display panel manufacturing process of Example 4 by this invention. FIG. 16 is a sectional view taken along line AA in FIG. 15. The schematic partial top view of the board | substrate in the organic EL display panel manufacturing process of Example 4 by this invention. FIG. 18 is a cross-sectional view taken along line AA of FIG. The schematic partial top view of the board | substrate in the organic EL display panel manufacturing process of Example 4 by this invention. The schematic of the board | substrate in a vapor deposition apparatus and the vapor deposition source in the organic EL display panel manufacturing process of Example 4 by this invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of Example 5 by this invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of Example 5 by this invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of Example 5 by this invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of Example 5 by this invention. The schematic fragmentary sectional view of the board | substrate in the organic electroluminescent display panel manufacturing process of Example 5 by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light emitting pixel 2 Substrate 3 1st display electrode line 5 Non-linear element 7 Partition 7a Overhang part 8 Organic EL medium 9 Second display electrode line 10 Protective film 40 Insulating film 45 Sealing film

Claims (10)

An organic electroluminescence display panel having an image display array composed of a plurality of light emitting units,
A substrate on which a plurality of first display electrodes corresponding to the light emitting portion are formed;
A plurality of electrically insulating partition walls protruding on the substrate exposing at least a portion of the first display electrode;
A thin film of the organic electroluminescent medium of the small of Kutomo one layer formed on each of the exposed part of the first display electrode,
A plurality of second display electrodes formed on a thin film of the organic electroluminescence medium,
An overhang portion projecting in a direction parallel to the substrate on the partition;
The organic electroluminescence display panel, wherein the second display electrode is in non-contact with the partition on both sides of the partition. 2. The organic electroluminescence display panel according to claim 1, wherein an end portion of the second display electrode defines a light emitting pixel region in the vicinity of the partition wall. 2. The organic electroluminescence device according to claim 1, further comprising an insulating film formed on the first display electrode under the overhang portion or at least one of the edge portions of the exposed portion of the first display electrode. Luminescence display panel. The organic electroluminescence display panel according to claim 1, wherein the insulating film defines a light emitting pixel region. An insulating sealing film formed on the first display electrode, the thin film of the organic electroluminescence medium, and the second display electrode, and the insulating sealing film completely covers at least the second display electrode; The organic electroluminescence display panel according to any one of claims 1 to 4, wherein the organic electroluminescence display panel is provided. 2. The organic electroluminescence display panel according to claim 1, wherein the first display electrode and the second display electrode are a plurality of stripe-shaped electrodes and are arranged at positions orthogonal to each other. The organic electroluminescence display panel according to claim 1, wherein the substrate and the first display electrode are transparent. 8. The organic electroluminescence display panel according to claim 7, further comprising a reflective film formed on the second display electrode. The organic electroluminescence display panel according to claim 1, wherein the second display electrode is transparent. The organic electroluminescence display panel according to claim 9, further comprising a reflective film formed outside the first display electrode.

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