JP2009252613A - Organic el panel manufacturing method, organic el panel, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem in a method of forming a functional layer of an organic EL panel by using a droplet discharging method by evaporating a first solvent to form a temporary functional layer and supplying a second solvent by a spray coating method to form additional functional layer; that, when a solvent is supplied to the entire surface of the organic EL panel at a time, there is a density distribution of solvent atmosphere accompanied by evaporation of the solvent between the central portion and the peripheral portion of the organic EL panel and this causes a great distribution in the characteristics of the organic EL element. <P>SOLUTION: By using a droplet discharging method, a second solvent 223 is discharged to the functional regions 117 of an organic EL panel 1 and then evaporated so that a checkered pattern in planar view of regions 117 is drawn with the solvent in order to equalize the solvent evaporation rates in the functional regions 117 of the organic EL panel 1. Next a second solvent 223 is discharged to the adjoining functional regions 117A and evaporated. As the result, the gas atmosphere distribution of the second solvent 223 can be suppressed and an organic EL panel 1 having a uniform characteristic can be obtained. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an organic EL panel, an organic EL panel, and an electronic apparatus.

  Organic EL panels have a wider viewing angle than liquid crystal panels. In addition, since the organic EL element constituting the organic EL panel is a self-luminous element, it is superior in black expressive power as compared with a liquid crystal panel, and is highly evaluated as a next-generation display panel. The organic EL panel can emit light of three primary colors of RGB (R: red, G: green, B: blue) by changing the configuration of the organic functional layer, and thus has been developed as a color display. Yes.

  In the case where an organic EL element is used as an RGB display element, a technique for forming an organic functional layer by discharging a liquid organic functional layer precursor corresponding to each color to each pixel using a droplet discharge method and performing drying is known. It has been. By forming the organic functional layer using a droplet discharge method, the organic functional layer precursor can be supplied only to a region where the organic functional layer is to be formed. Therefore, there is an advantage that the amount of waste can be suppressed as compared with a method such as spin coating method, in which an organic functional layer precursor is applied to the entire surface of the substrate and then an area where the organic functional layer is unnecessary is etched away. Therefore, the environmental load can be reduced, the etching process can be omitted, and the amount of the expensive organic functional layer precursor used can be reduced, so that the TAT can be shortened and the manufacturing cost can be reduced. Examples of forming an organic EL element with high homogeneity in an organic EL panel using a droplet discharge method include Patent Document 1 and Patent Document 2.

  In Patent Document 1, an organic functional layer precursor is once discharged and dried in an organic EL element by a droplet discharge method to form an organic functional layer, and then a solvent is applied again by a spray coating method. A technique for improving the uniformity of layer quality in an organic EL panel by re-dissolving is shown. Moreover, in patent document 2, before discharging an organic functional layer precursor in an organic EL element, a solvent is discharged in an organic EL element, and an organic functional layer precursor is discharged continuously, and the drying time of ink is controlled. However, a technique for making the layer quality uniform is shown.

JP 2003-142261 A JP 2004-31070 A

  When the technique of Patent Document 1 is used, the solvent is supplied to the organic EL panel by a spray coating method. Therefore, the solvent is simultaneously supplied to the entire surface of the organic EL panel. In this case, the concentration of the solvent atmosphere accompanying the volatilization of the solvent differs between the central portion and the outer peripheral portion of the organic EL panel. Specifically, the concentration of the solvent atmosphere is high at the center of the organic EL panel, and the concentration of the solvent atmosphere is low at the outer periphery. Therefore, there is a problem that the time required for drying the solvent has a distribution in the organic EL panel and a large distribution occurs in the characteristics of the organic EL element.

  Moreover, when the technique of patent document 2 is used, since the time required for drying of a solvent becomes long, the drying time difference itself for every organic EL element becomes large. Therefore, there is a problem that a large distribution occurs in the layer quality of the organic functional layer in the organic EL panel.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A method for manufacturing an organic EL panel according to this application example is a method for manufacturing an organic EL panel in which a plurality of pixel regions are arranged in a matrix via partition walls, and (1) an organic functional layer Separating the first functional liquid in which the precursor is dissolved or dispersed in the first solvent into the pixel region apart from the partition; and (2) evaporating the first solvent from the first functional liquid. Forming the organic functional layer precursor separated from the partition; and (3) separately ejecting a second solvent into each of the pixel regions into the pixel region, A step of forming a second functional liquid by dissolving or dispersing again; and (4) a step of evaporating the second solvent sequentially from the second functional liquid to form an organic functional layer. To do.

  According to this, the organic functional layer precursor separated from the partition is formed, and then the organic functional layer precursor is again dissolved or dispersed using the second solvent to form a layer, thereby forming a stratification history (particularly, the partition Part) can be prevented from changing the layer shape. Therefore, it is possible to form a uniform layer as compared with a method of once stratifying and then dissolving and re-stratifying again. Further, the second solvent is discharged independently to each pixel region. For this reason, it is possible to remove the second solvent with the second solvent atmosphere concentration in the vicinity of each pixel region, and to form a uniform layer.

  Application Example 2 In the method for manufacturing an organic EL panel according to the application example, the boiling point of the second solvent is lower than the boiling point of the first solvent.

  According to the application example described above, by increasing the boiling point of the first solvent, it is possible to suppress ejection failure associated with dry fixation of the first functional liquid in the ejection unit when performing the ejection process. And by using the 2nd solvent which lowered | hanged the boiling point compared with the boiling point of the 1st solvent, the 2nd solvent is volatilized rapidly without a time lag on the organic EL panel whole surface. Therefore, the layer thickness fluctuation | variation of the organic functional layer resulting from the in-plane distribution of the drying time of a 2nd solvent is suppressed. Therefore, it is possible to obtain an organic functional layer having a uniform layer thickness on the entire surface of the organic EL panel.

  Application Example 3 In the method for manufacturing an organic EL panel according to the application example, the boiling point of the first solvent is 170 ° C. or more and 300 ° C. or less, and the boiling point of the second solvent is 70 ° C. or more and 150 ° C. or less. It is characterized by.

  According to the application example described above, as a result of the experiment, by using the first solvent having a boiling point of 170 ° C. or higher, it has succeeded in suppressing the discharge failure associated with the dry fixation of the first functional liquid in the discharge unit. . Moreover, the vacuum drying after discharging can be easily performed by using the 1st solvent which has a boiling point of 300 degrees C or less.

  Similarly, by using a second solvent having a boiling point of 70 ° C. or higher, transpiration that occurs during ejection can be suppressed, so that a time for dissolving or dispersing again is secured. As a result, it has succeeded in aligning the state of the organic functional layer on the entire surface of the organic EL panel. Moreover, the 2nd solvent discharged by using the 2nd solvent which has a boiling point of 150 degrees C or less rapidly evaporates, and generation | occurrence | production of the nonuniformity accompanying drying is suppressed.

  Application Example 4 In the method for manufacturing an organic EL panel according to the application example, the first solvent is cyclohexylbenzene, tetramethylbenzene, or a mixed solution of cyclohexylbenzene and tetramethylbenzene, and the second solvent is toluene. , Xylene, or a mixed liquid of toluene and xylene.

  According to the application example described above, as a result of the experiment, by using cyclohexyl benzene, tetramethyl benzene, or a mixed liquid of cyclohexyl benzene and tetramethyl benzene as the first solvent, the first functional liquid is dried and fixed in the discharge unit. It has succeeded in suppressing the discharge failure that accompanies this. Moreover, drying after discharging can be easily performed. Further, by using toluene, xylene, or a mixed solution of toluene and xylene as the second solvent, it is possible to align the state of the organic functional layer on the entire surface of the organic EL panel.

  Application Example 5 In the method of manufacturing the organic EL panel according to the application example, the second solvent is discharged in the pixel region located in the vertical direction of the matrix and in the horizontal direction of the matrix. Is performed in a region having a non-ejection state or a transpiration state.

    According to the application example described above, the volatile gas atmosphere of the second solvent generated in the adjacent pixel by discharging the second solvent to the pixel that satisfies the condition that the second solvent is not yet discharged or evaporated in the adjacent pixel. It becomes possible to suppress the influence of the transpiration rate. Therefore, it becomes possible to arrange the evaporation rate of the second solvent with high uniformity, and it is possible to obtain an organic functional layer having a uniform layer thickness on the entire surface of the organic EL panel.

  Application Example 6 An organic EL panel manufacturing method according to this application example is an organic EL panel manufacturing method in which a plurality of pixel regions are arranged in a matrix via partition walls, and (1) an organic functional layer A step of discharging a first functional liquid in which a precursor is dissolved or dispersed in a first solvent into the pixel region in a state of covering a part of the partition; and (2) the first functional liquid from the first functional liquid. A step of evaporating a solvent to form a layered organic functional layer precursor covering a part of the partition; and (3) separately discharging a second solvent into each of the pixel regions in the pixel region. A step of dissolving or dispersing the organic functional layer precursor again to form a second functional liquid; and (4) a step of evaporating the second solvent sequentially from the second functional liquid to form an organic functional layer. It is characterized by including these.

  According to this, the 2nd solvent is discharged independently with respect to each pixel area. For this reason, it is possible to remove the second solvent with the second solvent atmosphere concentration in the vicinity of each pixel region, and to form a uniform layer.

  Application Example 7 In the method of manufacturing an organic EL panel according to the application example, the boiling point of the second solvent is lower than the boiling point of the first solvent.

  According to the application example described above, by increasing the boiling point of the first solvent, it is possible to suppress ejection failure associated with dry fixation of the first functional liquid in the ejection unit when performing the ejection process. And by using the 2nd solvent which lowered | hanged the boiling point compared with the boiling point of the 1st solvent, the 2nd solvent is volatilized rapidly without a time lag on the organic EL panel whole surface. Therefore, the layer thickness fluctuation | variation of the organic functional layer resulting from the in-plane distribution of the drying time of a 2nd solvent is suppressed. Therefore, it is possible to obtain an organic functional layer having a uniform layer thickness on the entire surface of the organic EL panel.

  Application Example 8 In the method for manufacturing an organic EL panel according to the application example, the boiling point of the first solvent is 170 ° C. or more and 300 ° C. or less, and the boiling point of the second solvent is 70 ° C. or more and 150 ° C. or less. It is characterized by.

  According to the application example described above, as a result of the experiment, by using the first solvent having a boiling point of 170 ° C. or higher, it has succeeded in suppressing the discharge failure associated with the dry fixation of the first functional liquid in the discharge unit. . Moreover, the vacuum drying after discharging can be easily performed by using the 1st solvent which has a boiling point of 300 degrees C or less. Similarly, by using a second solvent having a boiling point of 70 ° C. or higher, transpiration that occurs during ejection can be suppressed, so that a time for dissolving or dispersing again is secured. As a result, it has succeeded in aligning the state of the organic functional layer on the entire surface of the organic EL panel. Moreover, the 2nd solvent discharged by using the 2nd solvent which has a boiling point of 150 degrees C or less rapidly evaporates, and generation | occurrence | production of the nonuniformity accompanying drying is suppressed.

  Application Example 9 In the method for manufacturing an organic EL panel according to the application example, the first solvent is cyclohexylbenzene, tetramethylbenzene, or a mixed solution of cyclohexylbenzene and tetramethylbenzene, and the second solvent is toluene. , Xylene, or a mixed liquid of toluene and xylene.

  According to the application example described above, as a result of the experiment, by using cyclohexyl benzene, tetramethyl benzene, or a mixed liquid of cyclohexyl benzene and tetramethyl benzene as the first solvent, the first functional liquid is dried and fixed in the discharge unit. It has succeeded in suppressing the discharge failure that accompanies this. Moreover, drying after discharging can be easily performed. Further, by using toluene, xylene, or a mixed solution of toluene and xylene as the second solvent, it is possible to align the state of the organic functional layer on the entire surface of the organic EL panel.

  Application Example 10 In the method for manufacturing an organic EL panel according to the application example, the second solvent is discharged in the pixel region located in the vertical direction of the matrix and in the horizontal direction of the matrix. Is performed in a region having a non-ejection state or a transpiration state.

  According to the application example described above, the volatile gas atmosphere of the second solvent generated in the adjacent pixel by discharging the second solvent to the pixel that satisfies the condition that the second solvent is not yet discharged or evaporated in the adjacent pixel. It becomes possible to suppress the influence of the transpiration rate. Therefore, it becomes possible to arrange the evaporation rate of the second solvent with high uniformity, and it is possible to obtain an organic functional layer having a uniform layer thickness on the entire surface of the organic EL panel.

  Application Example 11 In the method for manufacturing an organic EL panel according to the application example, a droplet discharge method is used for the discharging step.

  According to the application example described above, it is possible to provide droplets only to necessary portions, and thus it is possible to suppress the amount of waste generated. In addition, since the discharge amount can be precisely controlled, it is possible to obtain an organic functional layer having a uniform layer thickness over the entire surface of the organic EL panel.

  Application Example 12 An organic EL panel according to this application example is formed by using the above-described organic EL panel manufacturing method.

  According to this, the organic EL panel is manufactured including the above-described manufacturing method. Therefore, it is possible to provide an organic EL panel having high display quality as compared with the case where the conventional technique is used.

  Application Example 13 An electronic apparatus according to this application example includes the above-described organic EL panel.

  According to this, since an electronic device including the above-described organic EL panel can be provided, it is possible to provide an electronic device having a high display quality compared to the case where the conventional technique is used.

(Organic EL panel configuration)
Hereinafter, a configuration of an organic EL panel including an organic EL element obtained by using a method for manufacturing an organic EL element will be described with reference to the drawings.

  FIG. 1 is a schematic diagram showing a wiring structure of an organic EL panel. The organic EL panel 1 is of an active matrix type using thin film transistors (hereinafter referred to as TFTs) as switching elements, and has a plurality of scanning lines 101 and a direction that intersects each scanning line 101 at right angles. And a plurality of power lines 103 extending in parallel to each signal line 102 and a pixel (sub-pixel 40) near each intersection of the scanning line 101 and the signal line 102. Is provided.

  A data line driving circuit 100 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102. Further, a scanning line driving circuit 80 including a shift register and a level shifter is connected to the scanning line 101.

  Each of the sub-pixels 40 has a pixel signal formed by sharing the switching TFT 122 to which the scanning signal is supplied to the gate electrode via the scanning line 101 and the signal line 102 via the switching TFT 122. The holding capacitor 113 to be held, the driving TFT 123 to which the pixel signal held by the holding capacitor 113 is supplied to the gate electrode, and the power source line 103 are driven when electrically connected to the power source line 103 through the TFT 123. A pixel electrode (anode) 23 to which a current is applied, a counter electrode (cathode) 50 at a position facing the pixel electrode (anode) 23, and the pixel electrode (anode) 23 and the counter electrode (cathode) 50 are sandwiched between them. Organic EL elements 17 (R, G, B) (R (red), G (green), B (blue)) located at positions are provided.

Next, a specific aspect of the organic EL panel 1 of the present embodiment will be described with reference to FIG. Here, FIG. 2 is a plan view schematically showing the configuration of the organic EL panel 1.
As shown in FIG. 2, in the actual display area 4 on the substrate 20A, sub-pixels 40 provided corresponding to R, G, and B are regularly arranged in a matrix. Here, the substrate 20A includes a substrate body 20 and TFTs 122 and 123 (see FIG. 1) provided on the substrate body 20, for example.

  The sub-pixels 40 (R, G, B) of R, G, and B colors constitute a display unit pixel 41 as one basic unit. In addition, each of the sub-pixels 40 (R, G, B) has an organic EL element 17 corresponding to red light emission (R), green light emission (G), and blue light emission (B) as the TFTs 122 and 123 operate. (R, G, B) (see FIG. 1). Thus, the display unit pixel 41 has a configuration for performing full color display by mixing R, G, and B light emission.

  In the present embodiment, the pixel unit 3 includes an actual display area 4 in the center (within the two-dot chain line in the figure) and a dummy area 5 (one-dot chain line and two-dot chain line) arranged around the actual display area 4. Between the two areas). Further, scanning line driving circuits 80 are arranged on both sides of the actual display region 4 in FIG. The scanning line driving circuit 80 is provided on the lower layer side of the dummy region 5.

  Further, an inspection circuit 90 is disposed above the actual display area 4 in FIG. 2, and the inspection circuit 90 is disposed on the lower layer side of the dummy area 5. The inspection circuit 90 is a circuit for inspecting the operating state of the organic EL panel 1, and includes, for example, inspection information output means (not shown) for outputting inspection results to the outside, It is configured so that the quality and defect inspection of the EL panel can be performed.

(Manufacturing method of an organic EL element-1: a method of forming an organic functional layer precursor apart from a partition wall)
Hereinafter, the manufacturing method of the organic EL element which comprises an organic EL panel is demonstrated using drawing. 3A, 3B, 4A, 4B, 5A, and 5B show a method for manufacturing the organic EL element 17 (R, G, B) shown in this embodiment. It is process sectional drawing for demonstrating. Hereinafter, description will be made with reference to this drawing. For convenience of explanation, the upper side of the drawing is defined as “upper”.

  First, as step 1, a substrate 20A formed by forming TFT 122, TFT 123 (see FIG. 1), etc. on a substrate body 20 (see FIG. 2) using a transparent member such as glass is cleaned to form an interlayer insulating layer 202. A silicon nitride layer is deposited to a thickness of about 400 nm using a CVD method (chemical vapor deposition method) or the like.

  Next, as process 2, ITO is laminated | stacked using a sputtering method so that it may become a thickness of about 50 nm. Then, the anode 204 having light transmittance is formed by etching away unnecessary portions.

  Next, as step 3, a silicon oxide layer is formed to a thickness of about 50 nm, and a region where the light emitting region 211 is formed is removed by etching to form a first partition 205.

  Next, as step 4, a photosensitive acrylic resin is applied to a thickness of about 2 μm, and exposed and developed to form the second partition 206. The planar dimension of the functional region 117 (see FIG. 6) inside the second partition 206 has a substantially rectangular shape with a shape of about 150 μm × 50 μm, for example.

  Next, as step 5, oxygen plasma treatment, plasma treatment with carbon tetrafluoride gas, or the like is performed to impart lyophilicity to the anode 204 and the first partition 205, and to impart lyophobicity to the second partition 206.

  Next, as Step 6, the PEDOT / PSS dispersion is discharged into the second partition 206 using a droplet discharge method. In this case, since the second partition wall 206 is given liquid repellency, the PEDOT / PSS dispersion liquid is repelled in the second partition wall 206 and flows onto the first partition wall 205 and the anode 204, so Some deviation is corrected, and the droplets are arranged on the first partition 205 and the anode 204 with high reproducibility.

  Next, as a process 7, a hole injection layer 207 as a carrier injection layer using PEDOT / PSS is formed by performing a drying process or the like. FIG. 3A shows a cross-sectional view after this process is completed. The thickness of the hole injection layer 207 is preferably about 20 nm, for example.

  Next, as Step 8, the organic functional layer precursor liquid 220 is discharged into the second partition 206 using a droplet discharge method so as not to touch the second partition 206. In this case, as the first solvent 222 constituting the organic functional layer precursor liquid 220, it is preferable to use a solvent having a boiling point of 170 ° C. or higher and 300 ° C. or lower, such as cyclohexylbenzene or tetramethylbenzene. The organic functional layer 224 (see FIG. 5A) includes polyfluorene polymer derivatives, perylene dyes, coumarin dyes, rhodamine dyes, rubrene, perylene, and 9,10-diphenylanthracene. It is possible to use a substance doped with tetraphenylbutadiene, nile red, coumarin 6, quinacridone, etc., and RGB primary colors can be obtained by using one or a mixture of these dopants.

  Here, when the boiling point of the first solvent 222 has a value of 170 ° C. or more, when the droplet is discharged, the droplet discharge is performed in a state where the ejection unevenness caused by the evaporation of the solvent near the discharge head is suppressed. Can be done. Moreover, it becomes possible to evaporate the 1st solvent 222 using a vacuum drying method by having a boiling point of 300 degrees C or less.

  The concentration of the material added to form the organic functional layer 224 (see FIG. 5A) in the first solvent 222 is preferably about 3 wt%. By using such a concentration, the layer thickness of the organic functional layer 224 can be secured, and the viscosity can be suppressed to such an extent that ejection can be easily performed. FIG. 3B shows a cross-sectional view after this step is finished and the organic functional layer precursor liquid 220 is discharged.

  Next, as step 9, vacuum drying is performed. By performing a vacuum drying process, the 1st solvent 222 evaporates and the organic functional layer precursor 221 is formed. The organic functional layer precursor 221 is formed so as not to touch the second partition 206. FIG. 4A shows a cross-sectional view after the process is completed.

  Thus, by forming the organic functional layer precursor 221, a change (history) in the surface state that occurs when the organic functional layer precursor 221 touches the second partition 206 does not occur. Therefore, it is possible to form the organic functional layer 224 (see FIG. 5A) with higher uniformity.

  Next, as Step 10, the second solvent 223 having a boiling point of 70 ° C. or higher and 150 ° C. or lower is discharged into the second partition 206. As the second solvent 223 used here, for example, toluene, xylene, or a mixed solution of toluene and xylene is preferably used. In this discharging step, the organic functional layer precursor 221 is dissolved or dispersed again, and once becomes a liquid, spreads in the second partition 206 in a film shape. FIG. 4B shows a cross-sectional view after this process is completed.

  Then, the organic functional layer 224 is formed by evaporating the second solvent 223. This step easily proceeds at atmospheric pressure, and the film-like organic functional layer 224 can be formed without using a technique such as a vacuum drying method. FIG. 5A shows a cross-sectional view after this process is completed.

  Here, the process 10 will be described in more detail. FIG. 6A is a plan view showing a state in which the organic functional layer precursor 221 is disposed in the functional region 117 partitioned by the second partition 206 in a matrix, and FIG. 6 is a plan view showing a state immediately after the solvent 223 is discharged. FIG.

  As shown in FIG. 6A, when the organic functional layer precursor 221 discharges the second solvent 223 into the region partitioned by the second partition wall 206, the second organic functional layer precursor 221 enters the functional region 117A adjacent in the vertical and horizontal directions. The organic functional layer 224 is preferably formed by discharging the second solvent 223 into the functional region 117 where the solvent 223 does not remain and evaporating the second solvent 223. By discharging the second solvent 223 under these conditions, the generation of the second solvent 223 atmosphere from the functional region 117A can be suppressed. Therefore, it is possible to make the transpiration rate in the functional region 117 uniform in the organic EL panel 1 (see FIG. 2). Therefore, drying unevenness of the organic functional layer 224 generated by performing the transpiration process can be suppressed, and the organic EL panel 1 with high uniformity can be formed.

  The organic functional layer precursor 221 is formed so as not to touch the second partition 206. Therefore, the change (history) of the surface state in the second partition 206 generated when the organic functional layer precursor 221 touches the second partition 206 does not occur. Therefore, it becomes possible to form the organic functional layer 224 with higher uniformity. Further, by performing this step, it is possible to improve uniformity in the functional region 117, and the organic functional layer 224 (see FIG. 5A) is not partially disposed in the functional region 117 ( It is possible to suppress the occurrence of so-called film loss.

  Thus, as a discharge pattern for aligning the transpiration rate in the functional region 117, the second solvent 223 is discharged to the functional region 117 hatched in FIG. 6A as shown in FIG. 6B. After evaporating the second solvent 223 included in the functional region 117, a process of discharging the second solvent 223 into the functional region 117A without hatching may be used. Note that although the example in which the second solvent 223 is discharged in a checkered pattern is described here, a process such as discharging the second solvent 223 with two or more gaps may be used. When the transpiration rate is faster than the discharge rate, the discharge process may be performed after the adjacent functional region 117A (even in this case, the second solvent 223 does not remain in the adjacent functional region 117A. Becomes). Here, the layer thickness of the organic functional layer 224 is preferably about 20 to 30 nm, for example.

  Next, as step 11, a cathode 225 using calcium having a thickness of about 5 nm is formed. Then, an organic EL element 17 (R, G, B) shown in FIG. 5B is formed by forming a light reflecting layer 226 using aluminum having a layer thickness of 200 nm or more so as to cover the cathode 225. Is done.

  Here, the manufacturing method of the bottom emission type organic EL element 17 (R, G, B) for extracting light through the transparent substrate 20A has been described, but this is easily changed to the top emission type manufacturing process. It is possible. That is, by adding a step of forming a reflective layer such as aluminum having a thickness of 200 nm or more between the transparent substrate 20A and the interlayer insulating layer 202, the reflectance on the substrate 20A side is increased, and the optical transparency is obtained. By using Mg / Ag which is resistant to oxidation as the cathode and excluding the manufacturing process of the light reflecting layer 226, a process of obtaining a top emission type structure can be obtained. Further, by omitting the step of forming the light reflecting layer 226 and not performing the step of forming another reflecting layer, it is possible to obtain a structure that can be viewed on both sides.

(Manufacturing method of an organic EL element-2: Method of forming an organic functional layer precursor in contact with a partition wall)
Hereinafter, the manufacturing method of the organic EL element which comprises an organic EL panel is demonstrated using drawing. Since this manufacturing method has many parts in common with the above-described (organic EL element manufacturing method-1), the common parts are appropriately cited to avoid duplication. 7A, 7B, 8A, 8B, 9A, and 9B show a method for manufacturing the organic EL element 17 (R, G, B) shown in this embodiment. It is process sectional drawing for demonstrating. Hereinafter, description will be made with reference to this drawing. For convenience of explanation, the upper side of the drawing is defined as “upper”.

  From Step 1 to Step 7, the same manufacturing steps as in (Organic EL Element Manufacturing Method-1) are used.

  In step 8, the organic functional layer precursor liquid 220 is discharged using a droplet discharge method so as to form a film shape covering the hole injection layer 207 in the second partition wall 206. In this case, as the first solvent 222 constituting the organic functional layer precursor liquid 220, it is preferable to use a solvent having a boiling point of 170 ° C. or higher and 300 ° C. or lower, such as cyclohexylbenzene or tetramethylbenzene. The organic functional layer 224 (see FIG. 8B) includes polyfluorene polymer derivatives, perylene dyes, coumarin dyes, rhodamine dyes, rubrene, perylene, and 9,10-diphenylanthracene. It is possible to use a substance doped with tetraphenylbutadiene, Nile red, coumarin 6, quinacridone, or the like, and RGB primary colors can be obtained by mixing one or more of these dopants.

  Here, when the boiling point of the first solvent 222 has a value of 170 ° C. or more, when the droplet is discharged, the droplet discharge is performed in a state where the ejection unevenness caused by the evaporation of the solvent near the discharge head is suppressed. Can be done. Moreover, it becomes possible to evaporate the 1st solvent 222 using the vacuum drying method performed at the following process by having a boiling point of 300 degrees C or less. The concentration of the material added to constitute the organic functional layer 224 (see FIG. 8B) in the first solvent 222 is preferably about 0.5 to 1.5 wt%. By using such a concentration, it is possible to suppress the viscosity so that the discharge can be easily performed, and it is possible to obtain a high discharge amount reproducibility. FIG. 7A shows a cross-sectional view after this process is completed.

  Next, as the process 9, the organic functional layer precursor 221 is formed by performing a vacuum drying process. The organic functional layer precursor 221 is formed with a film-like structure in contact with the second partition 206 as illustrated. FIG. 7B shows a cross-sectional view after this process is completed.

  Thus, by forming the organic functional layer precursor 221, contact between the second solvent 223 (see FIG. 8A) and the hole injection layer 207 in the next step can be suppressed. Therefore, it is possible to suppress the influence on the characteristics of the hole injection layer 207 and to form the organic functional layer 224 (see FIG. 8B) with high uniformity.

  Next, as Step 10, the second solvent 223 having a boiling point of 70 ° C. or higher and 150 ° C. or lower is discharged into the second partition 206. As the second solvent 223 used here, for example, toluene, xylene, or a mixed solution of toluene and xylene is preferably used. In this discharging step, the organic functional layer precursor 221 is dissolved or dispersed again, and once becomes a liquid, spreads in the second partition 206 in a film shape. FIG. 8A shows a cross-sectional view after this process is completed.

  Then, the organic functional layer 224 is formed by evaporating the second solvent 223. This step easily proceeds at atmospheric pressure, and the film-like organic functional layer 224 can be formed without using a technique such as a vacuum drying method. FIG. 8B shows a cross-sectional view after this process is completed.

  Here, the process 10 will be described in more detail. FIG. 10A is a plan view showing a state in which the organic functional layer precursor 221 is arranged in the functional region 117 partitioned by the second partition 206 in a matrix. FIG. 10B is a plan view showing a state immediately after discharging the second solvent. As shown in FIG. 10B, when the second solvent 223 is discharged into the region partitioned by the second partition 206, the second solvent 223 does not remain in the functional region 117A adjacent in the vertical and horizontal directions. In the state, it is preferable to discharge the second solvent 223 into the functional region 117 and evaporate the second solvent 223 to form the organic functional layer 224 (see FIG. 8B). By discharging the second solvent 223 under these conditions, fluctuation of the transpiration time due to the atmosphere of the second solvent 223 from the functional region 117A can be suppressed. For this reason, the evaporation rate in the functional region 117 can be made uniform in the organic EL panel 1. Therefore, drying unevenness of the organic functional layer 224 (see FIG. 8B) generated by performing the transpiration process can be suppressed, and the organic EL panel 1 with high uniformity can be formed.

  As described above, as a discharge pattern for adjusting the transpiration rate in the functional region 117, the second solvent 223 is discharged to the hatched functional region 117 in FIG. After removing the solvent 223, a process such as discharging the second solvent 223 into the functional area 117A without hatching may be used. Note that although the example in which the second solvent 223 is discharged in a checkered pattern is described here, a process such as discharging the second solvent 223 with two or more gaps may be used. When the transpiration rate is faster than the discharge rate, the discharge process may be performed after the adjacent functional region 117A (even in this case, the second solvent 223 does not remain in the adjacent functional region 117A. Becomes). Here, the layer thickness of the organic functional layer 224 is preferably about 20 to 30 nm, for example.

  Next, as step 11, a cathode 225 using calcium having a thickness of about 5 nm is formed. Then, by forming a light reflection layer 226 using aluminum having a layer thickness of 200 nm or more so as to cover the cathode 225, the organic EL element 17 (R, G, B) shown in FIG. 9 is formed.

  Here, the manufacturing method of the bottom emission type organic EL element 17 (R, G, B) for extracting light through the transparent substrate 20A has been described, but this is easily changed to the top emission type manufacturing process. It is possible. That is, by adding a step of forming a reflective layer such as aluminum having a thickness of 200 nm or more between the transparent substrate 20A and the interlayer insulating layer 202, the reflectance on the substrate 20A side is increased, and the optical transparency is obtained. By using Mg / Ag which is resistant to oxidation as the cathode and excluding the manufacturing process of the light reflecting layer 226, a process of obtaining a top emission type structure can be obtained. Further, by omitting the step of forming the light reflecting layer 226 and not performing the step of forming another reflecting layer, it is possible to obtain a structure that can be viewed on both sides.

(Example of mounting on electronic equipment)
Next, an electronic device using the above manufacturing method will be described. 11A to 11C illustrate mounting examples of electronic devices including the organic EL panel 1 using the organic EL elements 17 (R, G, B) shown in FIGS. 5B and 9 described above. To do. FIG. 11A shows a configuration of a mobile personal computer 2000 provided with the organic EL panel 1. The personal computer 2000 includes the organic EL panel 1 and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002. FIG. 11B shows a configuration of a mobile phone 3000 provided with the organic EL panel 1. The cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and the organic EL panel 1 as a display unit. By operating the scroll button 3002, the screen displayed on the organic EL panel 1 is scrolled. FIG. 11C shows the configuration of a personal digital assistant PDA (Personal Digital Assistants) 4000 to which the organic EL panel 1 is applied. The information portable terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and the organic EL panel 1 as a display unit. When the power switch 4002 is operated, various types of information such as an address book and a schedule book are displayed on the organic EL panel 1.

  The electronic devices on which the organic EL panel 1 is mounted include those shown in FIG. 11, a digital still camera, a liquid crystal television, a viewfinder type, a monitor direct-view type video tape recorder, a car navigation device, a pager, an electronic notebook, Examples include a calculator, a word processor, a workstation, a videophone, a POS terminal, and a device equipped with a touch panel. And the organic EL panel 1 mentioned above is applicable as a display part of these various electronic devices.

The schematic diagram which shows the wiring structure of an organic electroluminescent panel. The top view which shows the structure of an organic electroluminescent panel typically. (A), (b) is process sectional drawing for demonstrating the manufacturing method of an organic EL element. (A), (b) is process sectional drawing for demonstrating the manufacturing method of an organic EL element. (A), (b) is process sectional drawing for demonstrating the manufacturing method of an organic EL element. (A) is a plan view showing a state in which an organic functional layer precursor is disposed in a functional region partitioned in a matrix by the second partition walls, and (b) is a state immediately after the second solvent is discharged. FIG. (A), (b) is process sectional drawing for demonstrating the manufacturing method of an organic EL element. (A), (b) is process sectional drawing for demonstrating the manufacturing method of an organic EL element. (A), (b) is process sectional drawing for demonstrating the manufacturing method of an organic EL element. (A) is a plan view showing a state in which an organic functional layer precursor is disposed in a functional region partitioned in a matrix by the second partition walls, and (b) is a state immediately after the second solvent is discharged. FIG. (A) is a schematic diagram of a mobile personal computer including an organic EL panel, (b) is a schematic diagram of a mobile phone, and (c) is a schematic diagram of an information portable terminal.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Organic EL panel, 3 ... Pixel part, 4 ... Actual display area, 5 ... Dummy area, 17 ... Organic EL element, 20 ... Substrate body, 20A ... Substrate, 40 ... Subpixel, 41 ... Display unit pixel, 80 ... Scanning line driving circuit, 90 ... inspection circuit, 100 ... data line driving circuit, 101 ... scanning line, 102 ... signal line, 103 ... power supply line, 113 ... holding capacitor, 117 ... functional area, 117A ... functional area, 122 ... TFT , 123 ... TFT, 202 ... interlayer insulating layer, 204 ... anode, 205 ... first partition, 206 ... second partition, 207 ... hole injection layer, 211 ... light emitting region, 220 ... organic functional layer precursor liquid, 221 ... organic Functional layer precursor, 222 ... first solvent, 223 ... second solvent, 224 ... organic functional layer, 225 ... cathode, 226 ... light reflecting layer, 2000 ... personal computer, 2001 ... power switch, 2002 Keyboard, 2010 ... the main body portion, 3000 ... mobile phone, 3001 ... operation button, 3002 ... scroll button, 4000 ... portable information terminal, 4001 ... operation button, 4002 ... power switch.

Claims (13)

A method for manufacturing an organic EL panel in which a plurality of pixel regions are arranged in a matrix via partition walls,
(1) a step of discharging a first functional liquid obtained by dissolving or dispersing an organic functional layer precursor in a first solvent into the pixel region apart from the partition;
(2) evaporating the first solvent from the first functional liquid to form the organic functional layer precursor separated from the partition;
(3) In the pixel region, a second solvent is separately discharged into each pixel region, and the organic functional layer precursor is dissolved or dispersed again to form a second functional liquid;
(4) a step of evaporating the second solvent sequentially from the second functional liquid to form an organic functional layer;
The manufacturing method of the organic electroluminescent panel characterized by including.   2. The method of manufacturing an organic EL panel according to claim 1, wherein the boiling point of the second solvent is lower than the boiling point of the first solvent.   It is a manufacturing method of the organic electroluminescent panel of Claim 2, Comprising: The boiling point of the said 1st solvent is 170 degreeC or more and 300 degrees C or less, The boiling point of the said 2nd solvent is 70 degreeC or more and 150 degrees C or less, It is characterized by the above-mentioned. A method for producing an organic EL panel.   4. The method of manufacturing an organic EL panel according to claim 3, wherein the first solvent is cyclohexylbenzene, tetramethylbenzene, or a mixed liquid of cyclohexylbenzene and tetramethylbenzene, and the second solvent is toluene, xylene. Or a mixed solution of toluene and xylene.   5. The method of manufacturing an organic EL panel according to claim 1, wherein the discharge of the second solvent is performed in the pixel region located in the vertical direction of the matrix and in the horizontal direction of the matrix. The method for producing an organic EL panel, which is performed in a region where the second solvent is not ejected or is evaporated. A method for manufacturing an organic EL panel in which a plurality of pixel regions are arranged in a matrix via partition walls,
(1) discharging a first functional liquid obtained by dissolving or dispersing an organic functional layer precursor in a first solvent into the pixel region in a state of covering a part of the partition;
(2) a step of evaporating the first solvent from the first functional liquid to form a layered organic functional layer precursor covering a part of the partition;
(3) In the pixel region, a second solvent is separately discharged into each pixel region, and the organic functional layer precursor is dissolved or dispersed again to form a second functional liquid;
(4) a step of evaporating the second solvent sequentially from the second functional liquid to form an organic functional layer;
The manufacturing method of the organic electroluminescent panel characterized by including.   It is a manufacturing method of the organic electroluminescent panel of Claim 6, Comprising: The boiling point of the said 2nd solvent is low compared with the boiling point of the said 1st solvent, The manufacturing method of the organic electroluminescent panel characterized by the above-mentioned.   The organic EL panel manufacturing method according to claim 7, wherein the boiling point of the first solvent is 170 ° C. or more and 300 ° C. or less, and the boiling point of the second solvent is 70 ° C. or more and 150 ° C. or less. A method for manufacturing an organic EL panel.   9. The method of manufacturing an organic EL panel according to claim 8, wherein the first solvent is cyclohexylbenzene, tetramethylbenzene, or a mixed liquid of cyclohexylbenzene and tetramethylbenzene, and the second solvent is toluene, xylene. Or a mixed solution of toluene and xylene.   10. The method of manufacturing an organic EL panel according to claim 6, wherein the second solvent is discharged in the pixel region located in the vertical direction of the matrix and in the horizontal direction of the matrix. The method for producing an organic EL panel, which is performed in a region where the second solvent is not ejected or is evaporated.   11. The method of manufacturing an organic EL panel according to claim 1, wherein a droplet discharge method is used in the discharging step. 11.   It forms using the manufacturing method of the organic electroluminescent panel as described in any one of Claims 1-11, The organic electroluminescent panel characterized by the above-mentioned.   An electronic apparatus comprising the organic EL panel according to claim 12.

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