JP2007004993A - Organic el device, its manufacturing method, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL device wherein contrast is not deteriorated even if used under outdoor daylight by suppressing the excitation of an organic EL material by outdoor daylight, and its manufacturing method. <P>SOLUTION: This organic EL device having respective pixel electrodes 31-33 arranged in a matrix shape on a substrate 102, a counter electrode 118 facing the respective pixel electrodes 31-33, and three types of organic electroluminescent layers 116 existing between the respective pixel electrodes 31-33 and the counter electrode 118 to emit red, green, and blue, respectively, for every pixel electrode is equipped with respective pigment thin films 71-73 for absorbing light having a wavelength capable of exciting the types of organic luminescent layers between the organic luminescent layer and a display surface. Thereby, the excitation of the organic EL material by outdoor daylight is suppressed, and the deterioration of contrast can be suppressed even if used under the outdoor daylight. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic EL device, a manufacturing method thereof, and an electronic device including the organic EL device.

  One type of self-luminous display device is an EL device using electroluminescence (hereinafter referred to as EL). EL is a phenomenon in which when a voltage is applied to a substance sandwiched between a pair of electrodes and a current is passed, light is emitted by excitation of electrons. Depending on the substance used, organic EL and inorganic EL It is divided roughly into. In recent years, development of full-color organic EL devices using organic EL materials corresponding to three different primary colors of red, green, and blue has been promoted in order to achieve both a large screen size and low power consumption.

  Among both electrodes that sandwich the organic EL material, Al (aluminum), Mg (magnesium), or an alloy containing these metals is used for the back side electrode, that is, the electrode on the opposite side of the light extraction direction. There are many. This is because the work function is small and formation is easy. However, the electrode on the back side made of the above material reflects external light incident from the light extraction direction, and forms an image (image of an external scenery) separate from the light emitted from the EL on the device display surface. There is a possibility that the contrast of the apparatus can be lowered.

  Therefore, in the development process of the organic EL device, investigations have been made on the influence of external light (hereinafter referred to as external light), that is, means for suppressing the decrease in contrast. For example, Patent Document 1 proposes an organic EL device in which a circularly polarizing plate is disposed on the light extraction direction side of the device to suppress the influence of the electrode on the back side.

Japanese Patent Laid-Open No. 8-322138

  However, the organic EL device having the above configuration cannot suppress a decrease in contrast due to excitation of the organic EL material by external light. This is because the circularly polarizing plate suppresses the external light reflected by the electrode on the back side from reaching the device display surface and cannot prevent the external light from passing through the organic EL material. Many organic EL materials that are currently in practical use are excited not only by current but also by transmission of light to generate light emission. For this reason, the current organic EL device emits light on the entire display surface under the outside light such as outdoors, and the contrast is inevitably lowered.

  Therefore, an object of the present invention is to provide an organic EL device that suppresses excitation of an organic EL material by external light and suppresses a decrease in contrast when used under external light.

  In order to solve the above problems, an organic EL device according to the present invention includes a pixel electrode arranged in a matrix on a substrate, a counter electrode facing the pixel electrode, and a gap between the pixel electrode and the counter electrode. An organic EL device having three types of organic light-emitting layers that emit red, green, and blue for each pixel electrode, and at least one type of organic light-emitting layer among the organic light-emitting layers And a display surface, a light-shielding layer that absorbs light having a wavelength capable of exciting the organic light-emitting layer of the type is provided.

  The organic EL material used for the light emitting layer of the organic EL device has a property of not only emitting light when energized but also absorbing (absorbing) external light (light outside the device) to emit light. And the wavelength of the said external light to absorb is shorter than the wavelength of the light which this organic EL material light-emits. Therefore, if a transparent material having an appropriate hue is used as the light-shielding layer, it is possible to block light that can excite the light-emitting layer without substantially preventing light emission by energization of the organic EL material. Therefore, with such a configuration, it is possible to provide an organic EL device in which the light-emitting layer is excited by external light and unintentional light emission is suppressed, and a decrease in contrast is suppressed when used under external light.

  In addition, it is preferable that the ratio at which light emission is blocked by the light-shielding layer by energization of the red, green, and blue pixels is within 3%. This is because a decrease in luminance due to hindering light emission due to the energization is not preferable. However, implementation is possible even if it is hindered within 5%, 7% or even 10% or more. This is because the effect obtained by suppressing the unintentional light emission may exceed the loss due to the decrease in luminance, and the decrease in luminance can be dealt with by means such as an increase in applied voltage.

  Preferably, the light shielding layer is capable of blocking light having a wavelength below the upper limit, the upper limit being in the range of 440 nm to 570 nm, and the light shielding layer is disposed between the organic light emitting layer emitting red light and the display surface. Is formed.

  Among the three types of organic light emitting layers that emit red, green, and blue, respectively, the red type organic light emitting layer is most affected by external light. The organic EL material used for the red-type light emitting layer can absorb light having a wavelength up to 570 nm, but the peak of the absorption ratio (absorbance) is at a wavelength of incident light of 440 nm or less. . Therefore, with such a configuration, it is possible to effectively suppress the red light emitting layer from emitting light by external light, and it is possible to obtain an organic EL device in which a decrease in contrast is suppressed when used under external light.

  Preferably, a light-shielding layer capable of shielding light having a wavelength below the upper limit within the range of 440 nm to 570 nm is formed between the organic light-emitting layer emitting red light and the display surface of the organic EL device. In addition, a light shielding layer capable of blocking light having a wavelength below the upper limit with an upper limit in the range of 440 nm to 500 nm is formed between the organic light emitting layer emitting green light and the display surface.

  Of the three types of organic light emitting layers that emit red, green, and blue, respectively, the green type organic light emitting layer is affected by external light next to the red type. The organic EL material used for the green light-emitting layer can absorb light having a wavelength of up to 500 nm, but the absorption ratio (absorbance) starts to decrease when the wavelength of incident light exceeds 440 nm. Therefore, with this configuration, it is possible to suppress the influence of external light on the light emitting layer of green type (not only red), and obtain an organic EL device in which a decrease in contrast is further suppressed when used under external light. be able to.

  Preferably, the light shielding layer is capable of blocking light having a wavelength below the upper limit having an upper limit in the range of 440 nm to 500 nm, and the light shielding layer is disposed between the organic light emitting layer emitting red light and the display surface. And an organic light emitting layer that emits green light and the display surface.

  As described above, the organic EL material used for the red light emitting layer can absorb light having a wavelength of up to 570 nm. However, the absorption ratio (absorbance) starts to decrease when the wavelength of incident light exceeds 440 nm, and becomes considerably smaller than 500 nm (see FIG. 14). Further, as described above, the wavelength of light that can be absorbed by the green light emitting layer is up to 500 nm. Therefore, by using the above-described structure, that is, the light shielding layer common to the red type and the green type, and setting the upper limit of the light shielding wavelength range of the light shielding layer to 440 nm to 500 nm, It is possible to obtain an organic EL device in which a decrease in contrast is suppressed when the organic EL device is used under external light while suppressing an increase in cost while reducing the steps required for formation.

  Preferably, the display surface includes a film that blocks light having a wavelength equal to or shorter than the upper limit, the upper limit being in the range of 380 nm to less than 440 nm.

  With this configuration, it is possible to suppress the influence of external light on the blue-type light emitting layer, and it is possible to obtain an organic EL device in which a decrease in contrast is further suppressed when used under external light.

  Preferably, a light shielding layer capable of blocking light having an upper limit wavelength of 440 nm or less is formed between the organic light emitting layer emitting blue light and the display surface.

  The human eye does not sense light with a wavelength of 380 nm or less. In addition, since light with a wavelength of more than 380 nm and less than 440 nm is hardly sensed, even if the light with the wavelength is cut off, the display performance (light emission by current) is hardly affected. On the other hand, the organic light-emitting layer that emits blue light (as well as other types of organic light-emitting layers) can have low contrast due to the influence of external light. Therefore, with such a configuration, it is possible to obtain an organic EL device in which a decrease in contrast is further suppressed during use under external light without degrading display performance.

  Preferably, the light shielding layer also serves as the pixel electrode.

  By combining the light shielding layer with other components of the organic EL device, the number of steps for forming a thin film can be suppressed to the same level as that of a conventional organic EL device, and the effects of the present invention can be obtained while suppressing an increase in cost. Can do.

  Preferably, a hole injection layer is provided between the pixel electrode and the organic light emitting layer, and the light shielding layer also serves as the hole injection layer.

  By combining the light shielding layer with other components of the organic EL device, the number of steps for forming a thin film can be suppressed to the same level as that of a conventional organic EL device, and the effects of the present invention can be obtained while suppressing an increase in cost. Can do.

  Preferably, the light shielding layer is obtained by mixing a conductive transparent material with a pigment or dye having a property of absorbing light having a predetermined wavelength as an upper limit.

  With this configuration, the effect of the present invention can be obtained by the light-shielding layer having the required characteristics while suppressing the influence on the characteristics of other elements constituting the organic EL device.

  Preferably, the light shielding layer is formed between the pixel electrode and a switching element for controlling the pixel electrode, and the pixel electrode and the switching element are electrically connected without passing through the light shielding layer.

  With this configuration, the light shielding layer can be formed of an insulating material such as a resin containing a pigment or the like, and the effects of the present invention can be obtained while suppressing an increase in manufacturing cost.

  Preferably, the organic EL device has a circularly polarizing plate on the display surface.

  Since the pigment is a particle, it can absorb light of a certain range of wavelengths and diffusely reflect light of other wavelengths. Therefore, even when a light shielding layer mixed with a pigment is formed by carrying out the present invention, it is possible to prevent the external light irregularly reflected by the light shielding layer from being emitted from the display surface and reducing the contrast. .

  In order to solve the above problems, an electronic apparatus according to the present invention includes the above-described organic EL device as a display device.

  Since the organic EL device described above suppresses a decrease in contrast when used under external light, this configuration can provide an electronic device that exhibits stable display performance even when used under external light.

  In addition, in order to solve the above-described problems, an organic EL device manufacturing method according to the present invention includes a step of forming a pixel electrode on a substrate, and three light-emitting elements each emitting red, green, and blue on the pixel electrode. Forming an organic light emitting layer of a type, wherein the pixel electrode laminated with at least one type of organic light emitting layer among the pixel electrodes is mixed with a pigment It is characterized by being formed by dripping an ITO solution by an ink jet method and then curing it.

  When an inkjet method is used, a thin film can be formed only in a very limited region. Therefore, by implementing this manufacturing method, it becomes easy to mix different pigments for each electrode corresponding to each light emission type, and to block light of different wavelengths for each electrode. It is also possible to form a light shielding layer only on electrodes corresponding to any light emission type, for example, only on the electrodes of pixels that emit red light. Therefore, it becomes possible to provide an organic EL device having stable display performance in which a decrease in contrast is suppressed even under external light at a lower cost.

  In order to solve the above problems, a method for manufacturing an organic EL device according to the present invention includes a step of forming a pixel electrode on a substrate, a step of forming a hole injection layer on the pixel electrode, Forming three types of organic light-emitting layers that emit red, green, and blue on the hole injection layer, respectively, and includes at least one of the hole injection layers. The hole injection layer to be laminated with one type of organic light emitting layer is characterized by being formed by dripping and curing a liquid material in which a pigment is mixed and having a hole injection material as a solute by an inkjet method Yes.

  By mixing the pigment, a hue can be imparted to the hole injection layer, and a function as a light-shielding layer that absorbs light of a predetermined wavelength or less can be provided. Depending on the selection of the pigment to be mixed, the three different types of red, green, and blue can be imparted with different hues, and the hue can be imparted only to the hole injection layer of any color type. In addition, the hole injection layer of the organic EL device is generally formed by an ink jet method. Therefore, by implementing such a manufacturing method, the function of a light-shielding layer can be imparted to the hole injection layer of an arbitrary pixel without greatly changing the current manufacturing equipment and the like, and an organic EL in which a decrease in contrast is suppressed even under external light The apparatus can be easily provided.

  In addition, in order to solve the above-described problems, an organic EL device manufacturing method according to the present invention includes a step of forming a pixel electrode on a substrate, and three light-emitting elements each emitting red, green, and blue on the pixel electrode. Forming an organic light emitting layer of a type, wherein the pixel electrode laminated with at least one type of organic light emitting layer among the pixel electrodes is mixed with a pigment It is formed by sputtering using ITO as a target.

  The ITO thin film can be imparted with a hue without losing transparency and conductivity by mixing a pigment. Therefore, a pixel electrode having a function of a light shielding layer can be formed by an ITO thin film colored with a pigment. Further, the sputtering method can form a thin film with high film thickness uniformity. Therefore, by implementing this manufacturing method, it is possible to form a light shielding layer that also serves as a pixel electrode and has improved film thickness uniformity. Therefore, it is possible to obtain an organic EL device in which a decrease in contrast is suppressed even under external light and generation of color unevenness due to nonuniformity of the light shielding layer thickness is suppressed.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In addition, in each figure, in order to make each layer and each member into a size that can be recognized on the drawing, the scale is different for each layer and each member. In addition, descriptions that are unnecessary when describing the present invention are omitted.

(First embodiment)
FIG. 13 shows a cross-sectional view of the organic EL device according to the first embodiment of the present invention. A pixel emitting red light (hereinafter referred to as an R pixel), a pixel emitting green light (hereinafter referred to as a G pixel), and a pixel emitting blue light (hereinafter referred to as a B pixel). ), A total of three types of pixels are regularly arranged. Color display is possible by controlling the intensity of light emission of each pixel by the amount of current that is conducted. This is a bottom emission type organic EL device that extracts light from the back surface of the substrate 102. The pixel electrode is made of a transparent material, and the counter electrode 118 is made of a metal thin film. Hereinafter, the manufacturing process of the organic EL device according to the first embodiment of the present invention will be described with reference to FIGS.

  First, as shown in FIG. 1, a thin film transistor (hereinafter referred to as TFT) 104 is formed on a transparent substrate (hereinafter referred to as substrate) 102 as a switching element for driving the colored pixel electrodes 21 to 23 (see FIG. 8). A silicon oxide film 106 as an interlayer insulating film is formed on the upper layer. Since it is a bottom emission type, the substrate needs to be transparent. Further, since the pixel electrodes are formed in a matrix on the substrate 102, the TFTs 104 are also formed in a matrix.

  Next, as shown in FIG. 2, a part of the silicon oxide film is selectively removed by photolithography to form a contact hole 108 at a predetermined position on the TFT 104.

Next, as shown in FIG. 3, a polyimide film 110 is formed on the entire surface of the substrate 102, and further a plasma treatment of CF ₄ is performed on the surface. By the above treatment, fluorine atoms enter the surface of the polyimide film 110, and the surface of the polyimide film 110 becomes liquid repellent.

Next, as shown in FIG. 4, a part of the polyimide film 110 is selectively removed by photolithography, and a partition 112 is formed in the remaining part. Since FIG. 4 is a cross-sectional view, it seems that the partition walls 112 are formed in a striped pattern, but in actuality, it is formed in a grid pattern. Then, a substantially square portion surrounded by the partition 112 (a portion where the polyimide film 110 is selectively removed) is a pixel region of each type. Specifically, Ra is an R pixel region (region where pixels emitting red light are formed), Ga is a G pixel region (regions where pixels emitting green light are formed), and Ba is a B pixel region (blue). A region where pixels emitting light are formed). (The pixel area referred to here is an area that finally becomes a pixel.)
As described above, the surface of the polyimide film 110 has liquid repellency, while the material called polyimide exhibits lyophilicity particularly when the surface treatment is not performed, so that the partition wall 112 has liquid repellency on the upper surface, The side surface will be lyophilic.

  5 to 7, an ITO (indium tin oxide alloy) film that also serves as a light-shielding layer is formed in each pixel region Ra, Ga, Ba using a known inkjet method and a similarly known sol-gel method. It is a process to do. The sol-gel method is a method in which a sol obtained by alkoxideizing a metal is used as a gel that loses fluidity by hydrolysis and polycondensation reaction, and this gel is heated to obtain an oxide.

  As shown in FIG. 5, ITO sol Sr in which pigment fine particles 11 are dispersed is dropped from an nozzle 130 of an ink jet apparatus into an R pixel region Ra. Here, the pigment fine particles 11 have a property of absorbing light having a wavelength of 550 nm or less. Thereby, the ITO thin film formed by the hardening process mentioned later is provided with the property to interrupt | block by absorbing light with a wavelength of 550 nm or less, maintaining transparency and electroconductivity. Due to the nature of the pigment fine particles 11, the formed ITO thin film has an orange-yellow color. Note that since the upper surface of the partition 112 has liquid repellency, the dropped sol Sr can be prevented from flowing into the adjacent pixel region. The same applies to the dropping of sol Sg and sol Sb described later.

  Next, as shown in FIG. 6, ITO sol Sg in which pigment fine particles 12 are dispersed is dropped from a nozzle 130 of an ink jet device into a G pixel region Ga. Here, the pigment fine particles 12 having a property of absorbing light having a wavelength of 480 nm or less are used. Thereby, the ITO thin film formed by the hardening process mentioned later is provided with the property to interrupt | block by absorbing light with a wavelength of 480 nm or less, maintaining transparency and electroconductivity. The formed ITO thin film has a yellow color due to the properties of the pigment fine particles 12.

  Next, as shown in FIG. 7, ITO sol Sb, in which pigment fine particles 13 are dispersed, is dropped from a nozzle 130 of an ink jet apparatus into a B pixel region Ba. The pigment fine particles 13 used here have a property of absorbing light having a wavelength of 440 nm or less. Thereby, the ITO thin film formed by the hardening process mentioned later is provided with the property to interrupt | block by absorbing light with a wavelength of 440 nm or less, maintaining transparency and electroconductivity. Due to the properties of the pigment fine particles 13, the formed ITO thin film has a yellow-green color.

  Next, as shown in FIG. 8, the substrate 102 is heat-treated, and the fine particles 11, 12, and 13 of each pigment dropped onto the pixel regions Ra, Ga, and Ba by the steps shown in FIGS. The dispersed indium-tin sol (Sr, Sg, Sb) is cured to form a pixel electrode (hereinafter referred to as a colored pixel electrode) made of a colored ITO film. The ITO thin film on the R pixel region Ra becomes the R colored pixel electrode 21, the ITO film on the G pixel region Ga becomes the G colored pixel electrode 22, and the ITO film on the B pixel region Ba becomes the B colored pixel electrode 23. As described above, the colored pixel electrodes 21 to 23 exhibit different colors depending on the color of the pigment that has been dispersed.

  Next, as shown in FIG. 9, a liquid material (hereinafter referred to as a hole liquid material) obtained by dissolving a hole injection material in a solvent on each of the colored pixel electrodes 21 to 23 by a known ink jet method. C) is dropped.

  Then, as shown in FIG. 10, after the dropping of the hole liquid material C is completed, the solvent is removed by a drying / curing process to form the hole injection layer 114 on each of the colored pixel electrodes 21 to 23. The hole injection layer 114 is formed for the purpose of improving the light emission efficiency of the organic light emitting layer, and is common to the pixel regions Ra, Ga, and Ba regardless of the color type in this embodiment.

  Next, as shown in FIG. 11, an EL material is dissolved in a solvent on each of the colored pixel electrodes 21 to 23 (actually on the hole injection layer 114) by a known ink jet method. A liquid material (hereinafter referred to as EL liquid material) D is dropped. Since the upper surface of the partition 112 has liquid repellency, it is possible to avoid the EL liquid material D from flowing out onto the adjacent pixels as in the case of the liquid material C described above.

  Here, the solute (organic EL material) dissolved in the EL liquid material D needs to be different depending on the color type of light emission. For the EL liquid material D dropped onto the R colored pixel electrode 21, for example, rhodamine and its derivatives are used as the organic EL material. Similarly, for the EL liquid material D dropped on the G colored pixel electrode 22, for example, quinacridone and its derivatives are used, and for the EL liquid material D dropped on the B colored pixel electrode 23, for example, distyryl biphenyl and its Derivatives are used.

  Then, after the dropping of the EL liquid material D is completed, as shown in FIG. 12, the solvent is removed by a drying / curing process, and an organic material is formed on each of the colored pixel electrodes 21 to 23 (on the hole injection layer 114). A light emitting layer 116 is formed. Due to the difference in materials described above, the organic light emitting layer 116 on the R colored pixel electrode 21 emits red light, the organic light emitting layer 116 on the G colored pixel electrode 22 emits green light, and the organic light emitting layer 116 on the B colored pixel electrode 23. Emits blue light respectively.

  Finally, as shown in FIG. 13, the counter electrode 118 and the sealing layer 120 that are paired with the colored pixel electrodes 21 to 23 are formed on the upper surface of the substrate 102, and the back surface of the substrate 102 (pixel electrodes and the like are formed). The circularly polarizing plate 122 is pasted on the other side. Since the counter electrode has a common potential between all the pixels, the counter electrode is formed over the entire surface of the substrate 102 without the need for patterning that separates the pixels. Moreover, since this embodiment is a bottom emission type, transparency is not necessary. As the material of the counter electrode 118, a laminate of a calcium layer and an aluminum layer, an alloy of magnesium and silver, or the like is used, and the formation is performed by a sputtering method or the like.

  The sealing layer 120 is for protecting the counter electrode 118 and the like from moisture contained in the outside air, and is formed by applying a resin on the entire surface of the substrate 102 and curing it with heat or ultraviolet rays. The circularly polarizing plate 122 is for suppressing changes in the color tone of the display surface caused by pigment fine particles mixed in the colored pixel electrodes 21 to 23 irregularly reflecting external light.

  As described above, the ITO forming the colored pixel electrodes 21 to 23 is colored by being mixed with a pigment. Coloring means that light is blocked by absorbing light of a certain wavelength region.

  In general, an organic light emitting material used for an organic EL device has not only light emission by electroluminescence (electroluminescence) but also photoluminescence property that emits light by light (light irradiation). Specifically, each light emitting layer has a property that light having a wavelength less than or equal to the lower limit of the wavelength of light emitted from each light emitting layer generates light having substantially the same wavelength as that of light emitted by current. For this reason, when used under external light, the entire display surface emits light, and a phenomenon may occur in which the contrast decreases.

  As a countermeasure against this, a technique is adopted in which a film that blocks light of a predetermined wavelength or less is attached to the entire display surface (entire surface). The human eye cannot sense light having a wavelength of 380 nm or less, and hardly senses light in the range from more than 380 nm to 440 nm or less. Therefore, by attaching a film that blocks light having a wavelength below the upper limit within the range of 380 nm to less than 440 nm to the entire display surface, the light emitted from each light emitting layer is not adversely affected. This is because a decrease in contrast due to the above can be suppressed to some extent.

  However, the above method is not sufficient for R and G pixels. This is because the R and G pixels can be excited by light having a wavelength exceeding 440 nm. However, as long as a film is applied to the entire display surface, light exceeding 440 nm (included in the light emitted from the B pixel) cannot be blocked. .

  The present embodiment is for solving the above-mentioned problems. A pigment is mixed in each of the R, G, and B colored pixel electrodes 21 to 23 to block light having wavelengths different from the upper limit for each type of pixel electrode. A function of a possible light shielding layer is provided, and external light having a wavelength equal to or shorter than a lower limit region of light emitted from each of the R, G, and B light emitting layers (hereinafter referred to as light emission) is blocked. As a result, the light emission of each of the R, G, and B light emitting layers due to external light is suppressed, and a decrease in contrast is suppressed even when used under strong external light, thereby obtaining an organic EL device that exhibits stable display performance. ing.

  As described above, in the present embodiment, by forming a light-shielding layer that can block light having an optimum hue and a wavelength equal to or less than the optimum upper limit value on each of the R, G, and B types of pixels, A reduction in contrast during use under light is effectively suppressed, and at the same time, the manufacturing cost is reduced by eliminating the film sticking step.

  In addition, it is preferable to determine the amount of fine particles 11 to 13 of each pigment mixed in the colored pixel electrodes 21 to 23 from the viewpoint of the balance between the elimination of the influence of external light and the efficient use of power. Specifically, an amount capable of blocking 90% or more of external light that can excite each light emitting layer while transmitting 90% or more of the light emitted from each of the R, G, and B light emitting layers is preferable. This is because sufficient display performance can be ensured by transmitting about 90% of emitted light, and sufficient contrast can be obtained if outside light can be blocked by 90% or more.

  Here, in the above-described embodiment, the light shielding layer formed on the R-colored pixel electrode 21 is configured to block light having a wavelength shorter than 550 nm, but the upper limit is not limited to 550 nm. Absent. FIG. 14 shows the relationship between the intensity of emitted light and the wavelength of the organic EL material that generates red emitted light, and the relationship between the absorbance (absorption rate) and wavelength when irradiated with external light having a certain intensity. Show. As shown in the figure, since the wavelength of light emission (photoluminescence) due to external light is up to around 570 nm, the upper limit is preferably set to 570 nm in order to completely eliminate the influence of external light.

  However, on the other hand, the external light absorptance starts to decrease when the external light is 460 nm or more, and the slope becomes large when the external light is 480 nm or more, and becomes a considerably small value when the external light is 500 nm or more. Further, the lower limit of the wavelength of light emission (electroluminescence) due to electric current is around 520 nm. And the wavelength of the intersection of the light emission by the current and the light emission curve by the external light is around 540 nm. Therefore, it can be said that the upper limit is preferably 520 nm from the viewpoint of efficiently using the power applied to the organic EL device, and the upper limit from the viewpoint of the balance between the efficient use of power and the exclusion of the influence of external light. Is preferably 540 nm.

  In addition, in order to widen the range of wavelengths that can be absorbed, considering the possibility that the concentration and type of pigments mixed in the light shielding layer may need to be increased, the upper limit is set to 480 nm where the influence of external light starts to decrease rapidly. It is also preferable to set the upper limit to 460 nm, at which the influence of external light starts to decrease.

  Similarly, in the above-described embodiment, the light shielding layer formed on the G-colored pixel electrode 22 shields light having a wavelength shorter than 480 nm, but the upper limit is not limited to 480 nm. . FIG. 15 shows the relationship between the intensity of emitted light and the wavelength of the organic EL material that generates green emitted light, and the relationship between the absorbance (absorption rate) and wavelength when irradiated with external light of a certain intensity. Show. As shown in the figure, since the photoluminescence wavelength is up to around 500 nm, the upper limit is preferably set to 500 nm in order to completely eliminate the influence of external light.

  However, on the other hand, the external light absorptance starts to decrease when the wavelength of the external light is 440 nm or more, increases greatly when the wavelength is 450 nm or more, and rapidly decreases when the wavelength is 460 nm or more. Moreover, the lower limit of the wavelength of light emission (electroluminescence) due to electric current is around 460 nm. And the wavelength of the intersection of the light emission by the current and the light emission curve by the external light is around 480 nm. Therefore, from the viewpoint of efficiently using the power applied to the organic EL device, it can be said that the upper limit is preferably 460 nm. From the viewpoint of the balance between the efficient use of power and the influence of external light, the upper limit is set. It can be said that 480 nm is preferable.

  In addition, in order to widen the range of wavelengths that can be absorbed, considering the possibility that the concentration and type of pigments mixed in the light shielding layer may need to be increased, the upper limit of 450 nm at which the influence of external light begins to decrease rapidly is considered. It is also preferable to set the upper limit to 440 nm at which the influence of external light starts to decrease.

  In the above-described embodiment, the light shielding layer formed on the B-colored pixel electrode 23 shields light having a wavelength lower than 440 nm as an upper limit, but the upper limit is preferably in the range of 380 nm to 440 nm. The human eye cannot perceive light below 380 nm and can perceive light in the range of 380 nm to 440 nm.

  Therefore, the upper limit value should be 380 nm only from the viewpoint of efficient use of power, and the upper limit value should be 440 nm only from the viewpoint of eliminating the influence of external light. This is because the upper limit value should be set between the above two values from the viewpoint of the balance between use and elimination of the influence of external light.

(Second Embodiment)
FIG. 23 shows an organic EL device according to the second embodiment of the present invention. Similar to the first embodiment, this is a bottom emission type organic EL device in which three types of pixels of R, G, and B are regularly arranged. Hereinafter, the implementation procedure of this embodiment is demonstrated using FIGS. In addition, the same code | symbol is provided to the element corresponding to the element shown by FIGS. 1-13 concerning 1st Embodiment.

  First, as shown in FIG. 16, an ITO thin film 202 is formed on the entire surface of a substrate 102 on which a TFT 104 as a switching element, a silicon oxide film 106 as an interlayer insulating film, and a contact hole 108 are formed by a known sputtering method. . The R pixel region Ra, the G pixel region Ga, and the B pixel region Ba are determined by the above elements.

  Next, as shown in FIG. 17, the ITO thin film 202 is patterned by photolithography to form pixel electrodes 31 to 33 in the pixel regions Ra, Ga, and Ba. Unlike the first embodiment, no pigment is mixed in the ITO thin film 202 at this stage. Accordingly, all the three pixel electrodes 31 to 33 are colorless and transparent, and there is no difference, but in the future (see FIG. 23), three types of organic light emitting layers will be formed on the pixel electrodes in the same manner as in the first embodiment. For this reason, different symbols are assigned. Each pixel electrode 31 to 33 is electrically connected to the TFT 104 through the contact hole 108.

  Next, as shown in FIG. 18, a second silicon oxide film is formed on the substrate 102 on which the pixel electrodes 31 to 33 are formed, and is patterned by photolithography to form a lower partition 204. In FIG. 18, although it seems to be patterned in a striped pattern, in reality, a part of the pixel electrode overlaps with the pixel electrode, and the periphery of each of the pixel electrodes 31 to 33 is similar to the partition 112 in the first embodiment. It is formed to surround.

  Next, as shown in FIG. 19, a polyimide thin film is formed on the entire surface of the substrate 102 on which the pixel electrodes 31 to 33 and the like are formed, and is patterned by photolithography so that the center line is aligned with the lower partition wall 204. An upper partition wall 206 having a width slightly smaller than that of the lower partition wall 204 as viewed from the vertical direction is formed on the rust substrate. As shown in the figure, the lower partition 204 is partially covered with the upper partition 206, but both ends (as viewed from the cross-sectional direction) and side surfaces of the upper partition 204 are exposed.

Next, as shown in FIG. 20, the entire surface of the substrate 102 formed up to the upper partition 206 is subjected to CF ₄ plasma treatment. Fluorine atoms enter the surface of the upper partition 206 formed of polyimide, react with the carbon atoms contained in the polyimide, and (surface) becomes liquid repellent.

Next, as shown in FIG. 21, the entire surface of the substrate 102 formed up to the upper partition 206 is subjected to O ₂ plasma treatment. Residues or foreign matters are removed from the surfaces of the lower partition 204 and the pixel electrodes 31 to 33 by oxidation, so that the surface has lyophilic properties.

  Next, by the method shown in FIG. 5 of the first embodiment, an indium tin sol Br in which pigment fine particles 11 are dispersed is dropped onto the pixel electrode 31 from the nozzle 130 of the inkjet device, and the inkjet is applied to the pixel electrode 32. Indium-tin sol Bg in which pigment fine particles 12 are dispersed is dropped from a nozzle 130 of the apparatus. (Does not drop on the pixel electrode 33.) Then, the sol is cured, and as shown in FIG. 22, pigment fine particles 11 are mixed on the pixel electrode 31 to block light having a wavelength of 550 nm or less. A colored pixel electrode 41 is formed, and on the pixel electrode 32, a G-colored pixel electrode 42 in which pigment fine particles 12 are mixed to block light having a wavelength of 480 nm or less is formed.

  Thereafter, as in FIGS. 9 to 13 of the first embodiment, the hole injection layer 114 and the organic light emitting layer 116 are formed on the pixel electrodes 31 to 33, and the counter electrode is formed on the upper layer (over the entire surface of the substrate). 118 and the sealing layer 120 are formed, and the circularly polarizing plate 122 is attached to the back surface of the substrate 102 (the surface on which the pixel electrode or the like is not formed). The formation method, material, and the like of each element are the same as those in the first embodiment. Further, a UV cut filter 124 capable of blocking light having a wavelength of 440 nm or less is stuck on the circularly polarizing plate 122 to obtain the organic EL device shown in FIG.

  This embodiment is the same as the first embodiment in that an ITO thin film colored by a sol-gel method is formed, but is different in that it is used in combination with an ITO thin film formed by a normal method. That is, the ITO thin film of each pixel electrode 31-33 is formed by a normal method, and the ITO thin film colored by the inkjet method is formed thereon. An advantage of this embodiment is that an ITO thin film having a function of a light shielding layer can be formed only where necessary. In each pixel region Ra, Ga, Ba, since a colorless ITO thin film is formed by a known means, the function as a pixel can be maintained without forming an ITO thin film serving as a light-shielding layer thereon. Therefore, for example, the light shielding layer can be formed only on the R and G pixels without forming the light shielding layer on the B pixel (on the pixel electrode 33) which does not need to consider the excitation of the light emitting layer by external light. . In that case, two types of pigments are sufficient, and the cost can be reduced. Further, it is possible to further reduce the cost by forming a light shielding layer only on the R pixel.

  The UV cut filter 124 blocks light having a wavelength of 440 nm or less that can excite the B light emitting layer, and compensates for the absence of a light-shielding layer made of colored ITO on the pixel electrode 33. is there.

  Further, the upper limit of the wavelength that can be blocked by each light shielding layer is not limited to the above values (550 nm for the R pixel and 480 nm for the G pixel), as in the first embodiment. Further, the amount of pigment fine particles mixed in the R colored pixel electrode 41 and the G colored pixel electrode 42 is an amount capable of blocking 90% or more of external light capable of exciting each light emitting layer while transmitting 90% or more of the emitted light. Preferred points are the same as those in the first embodiment.

(Third embodiment)
FIG. 30 shows an organic EL device according to the third embodiment of the present invention. As in the first embodiment, this is a bottom emission type organic EL device in which three types of pixels of R, G, and B are made regular. The point that the light shielding layer is formed in the R pixel region Ra and the G pixel region Ga is the same as in the second embodiment, but the light shielding layer is formed in the R pixel region Ra and the G pixel region Ga. The second embodiment is different from the second embodiment in that the light shielding layer has the same color and the upper limit of the wavelength of light that can be blocked is unified to 500 nm. Hereinafter, the implementation procedure of this embodiment is demonstrated using FIGS. In addition, the same code | symbol is attached | subjected to the element corresponding to the element shown by FIGS. 1-13 concerning 1st Embodiment, and FIGS. 16-23 concerning 2nd Embodiment.

  First, as shown in FIG. 24, the TFT 104, the silicon oxide film 106, and the contact hole 108 are formed on the substrate 102 by the steps shown in FIGS. 1 to 3 of the first embodiment. As described in the first embodiment, an organic EL device in which three types of pixels of R, G, and B are regularly arranged is formed. At this stage, the R pixel region Ra, the G pixel region Ga, The B pixel area Ba is specified.

  Next, as shown in FIG. 25, a colored ITO thin film 302 is formed on the entire surface of the substrate 102 by sputtering. At the time of sputtering, an ITO target 300 in which pigment fine particles 14 are mixed in ITO as a target material is used instead of a normal ITO target. This is for forming a transparent and colored ITO thin film. Here, as the fine particles 14 of the pigment, those having a property of absorbing light having a wavelength of 500 nm or less are used. The ITO thin film formed by the pigment fine particles 14 has a yellow color.

  FIG. 26 shows an aspect in which an ITO thin film colored with a pigment is formed by sputtering. In normal magnetron sputtering, the substrate 102 and the ITO target 300 are disposed in the high vacuum chamber 303 so as to face each other. The side on which the target is disposed is a cathode 306, and a magnet 308 is disposed at the base as shown. When Ar gas is introduced into the high vacuum chamber 303 while applying a high DC voltage with the side on which the substrate 102 is disposed as the anode 304, (Ar gas) enters a plasma state. Then, Ar atoms accelerated by the electric field collide with the ITO target 300 as shown in the figure, and the ITO particles jump out and adhere onto the substrate 102 by the impact. At this time, since the pigment fine particles 14 also jump out at the same time, an ITO thin film mixed with the pigment fine particles 14 is formed on the surface of the substrate 102. The magnet 308 is for increasing the sputtering efficiency.

  The pigment fine particles 14 are different from the pigment fine particles 12 used in forming the G colored pixel electrode 22 in the first embodiment. However, since the upper limit of the wavelength of the light to be blocked is not so different (at 500 nm and 480 nm), the formed ITO thin film is substantially the same in color and yellow.

Next, by patterning the colored ITO film 302 by photolithography, as shown in FIG. 27, the G ₂ colored pixel electrode 51 in the R pixel region Ra, to form a G ₂ colored pixel electrode 52 in the G pixel region Ga. (Forming materials 51 and 52 are the same, but are formed at different positions.) At this stage, the colored ITO thin film 302 is not left in the B pixel region Ba, and no pixel electrode is formed. The G ₂ colored pixel electrode 51 and the G ₂ colored pixel electrode 52 are electrically connected to the TFT 104 through the contact hole 108.

Next, as shown in FIG. 28, an ITO thin film 202 is formed (again) on the entire surface of the substrate on which the G ₂ colored pixel electrode 51 and the G ₂ colored pixel electrode 52 are formed. The ITO thin film 202 is a normal one, that is, a colorless one not mixed with a pigment.

Next, as shown in FIG. 29, the ITO thin film 202 is patterned by photolithography to form colorless ITO pixel electrodes 31, 32, and 33 in the R pixel region Ra, the G pixel region Ga, and the B pixel region Ba. To do. The pixel electrode 33 is electrically connected to the TFT 104 through the contact hole 108. As shown in the drawing, on the R pixel region Ra, the G ₂ colored pixel electrode 51 colored by mixing fine pigment particles and the pixel electrode 31 made of colorless ITO overlap with each other at substantially the same position and in a planar shape. Yes. Similarly, on the G pixel area Ga, the G ₂ colored pixel electrode 52 colored by the mixing of pigment fine particles and the pixel electrode 32 made of colorless ITO are overlapped at substantially the same position and planar shape. The same method and steps as those shown in the first embodiment and the second embodiment are used to form the lower partition wall 204 on each of the pixel electrodes 31 to 33 through the same steps as in the second embodiment. Upper upper partition walls 206 are formed. Then, after performing CF ₄ plasma and O ₂ plasma, the hole injection layer 114 and the organic light emitting layer 116 are formed in the depression surrounded by the two layers of partition walls, and the counter electrode 118 is formed thereon (over the entire surface of the substrate). The sealing layer 120 is formed. Then, a circularly polarizing plate 122 and a UV cut filter 124 capable of blocking light having a wavelength of 440 nm or less are attached to the back surface (the surface on which the pixel electrode or the like is not formed) of the substrate 102, and the organic EL device shown in FIG. Get.

  The feature of this embodiment is that the light shielding layer is formed by sputtering. The pixel electrode of the organic EL device is generally formed by patterning an ITO thin film obtained by sputtering. Accordingly, as shown in the present embodiment, by using a sputter target mixed with pigment fine particles, a light shielding layer can be formed in the pixel region without any other change in the process or increase in equipment. In addition, since the thin film formed by sputtering has high film thickness uniformity, it is one of the characteristics that the flatness of the surface of the substrate 102 after the formation of the light shielding layer is improved.

  In this embodiment, the upper limit of the wavelength of light that can be blocked by the light shielding layer is set to 500 nm because the same light shielding layer is used for the R pixel and the G pixel. A numerical value is selected. Therefore, the upper limit value can be selected as long as it is applicable to both pixels, and is preferably 460 nm or 480 nm. The purpose of attaching the UV cut filter 124 to the back surface of the substrate 102 is the same as in the second embodiment.

The amount of fine pigment particles mixed in the G ₂ colored pixel electrodes 51 and 52 is preferably such that it can block 90% or more of external light that can excite the light emitting layer while transmitting 90% or more of the emitted light. This is the same as the first embodiment. Moreover, the pigment used for this embodiment uses the thing excellent in plasma resistance.

(Fourth embodiment)
FIG. 36 shows an organic EL device according to the fourth embodiment of the present invention. As in the first embodiment, three types of pixels of R, G, and B are regularly formed, and a light-shielding layer having a different upper limit of the wavelength of light that can be blocked is formed in each pixel region Ra, Ga, and Ba. Yes. Hereinafter, the implementation procedure of this embodiment is demonstrated using FIGS. 31-36. Elements corresponding to those shown in FIGS. 1 to 13 according to the first embodiment, FIGS. 16 to 23 according to the second embodiment, and FIGS. 24 to 30 according to the third embodiment. Are denoted by the same reference numerals.

First, a TFT 104, a silicon oxide film 106, and a contact hole 108 formed in a matrix are formed on the substrate 102 by the steps shown in FIGS. Next, an ITO thin film 202 is formed on the entire surface of the substrate by a sputtering method by the steps shown in FIGS. As in the second embodiment, no pigment or the like is mixed in the ITO thin film. Then, the ITO thin film 202 is patterned by photolithography to form pixel electrodes 31, 32, and 33 that are electrically connected to the TFT 104 through the contact holes 108 in the respective pixel regions Ra, Ga, and Ba. Further, after the formation of the lower partition 204 and the upper partition 206 of the upper layer by the steps shown in FIGS. 18 to 21, CF ₄ plasma and O ₂ plasma are formed, and the configuration shown in FIG. 31 is obtained. Each pixel region Ra, Ga, Ba is surrounded by the two layers of barrier ribs, and a recess having each pixel electrode 31 to 33 as a bottom is formed. Here, the hole injection layer formed in the R pixel region Ra is the R hole injection layer, the hole injection layer formed in the G pixel region Ga is the G hole injection layer, and the positive hole formed in the B pixel region Ba. The hole injection layer is referred to as a B hole injection layer (see FIG. 35).

  Next, as shown in FIG. 32, the liquid material Pr in which the fine particle 11 of the pigment is dispersed on the pixel electrode 31 with the hole injection material as a solute and used in the first embodiment is discharged from the nozzle 130 of the ink jet apparatus. Dripping.

  Next, as shown in FIG. 33, the liquid material Pg in which the fine particle 12 of the pigment is dispersed on the pixel electrode 32 using the hole injection material as a solute from the nozzle 130 of the ink jet apparatus, which is also used in the first embodiment. Dripping.

  Next, as shown in FIG. 34, the liquid material Pb in which the hole injecting material is used as a solute on the pixel electrode 33 and the pigment fine particles 13 are dispersed is used from the nozzle 130 of the ink jet apparatus. Dripping.

  Next, as shown in FIG. 35, the entire substrate 102 is heated to dry and cure the liquid materials Pr, Pg, and Pb on the pixel electrodes 31 to 33 to remove the solvent. Hole injection layers (114r, 114g, 114b) are formed. An R hole injection layer 114r that blocks light having a wavelength of 550 nm or less is formed on the pixel electrode 31, a G hole injection layer 114g that blocks light having a wavelength of 480 nm or less is formed on the pixel electrode 32, and the pixel electrode 33 A B hole injection layer 114b that blocks light having a wavelength of 440 nm or less is formed thereon.

  Finally, as shown in FIG. 36, an organic light emitting layer 116 that emits red, green, and blue is formed on each of the hole injection layers 114r, 114g, and 114b. A stop layer 120 is formed, and a circularly polarizing plate 122 is attached to the display surface to obtain an organic EL device.

  The feature of this embodiment is that the hole injection layer also serves as a light shielding layer. As described above, the organic light-emitting material used in the organic EL device also has the property of photoluminescence that emits light by irradiation. Specifically, each light emitting layer has a property that light having a wavelength less than or equal to the lower limit of the wavelength of light emitted from each light emitting layer generates light having substantially the same wavelength as that of light emitted by current. Due to its nature, the contrast of a general organic EL device is lowered when used under external light. However, each of the hole injection layers 114r, 114g, and 114b of the organic EL device according to the present embodiment is colored by mixing fine pigment particles, and is blocked by absorbing light of a certain wavelength region.

  Specifically, depending on the hue of the pigment, the R hole injection layer 114r emits light having a wavelength of 550 nm or less, the G hole injection layer 114g emits light of a wavelength of 480 nm or less, and the B hole injection layer 114b Light with a wavelength of 440 nm or less is blocked. This means that external light that can excite each of the R, G, and B light-emitting layers is blocked to a considerable extent. That is, as in the first embodiment, by forming a light-shielding layer that can block light having an optimum hue and a wavelength equal to or less than the optimum upper limit value on each of the R, G, and B type pixels, This effectively suppresses a decrease in contrast when the pixels are used under external light.

  In an organic EL device, particularly a polymer organic EL device, a light emitting layer or a hole injection layer sandwiched between electrodes is generally formed by an ink jet method. Therefore, by carrying out the manufacturing method according to the present embodiment, the current manufacturing equipment is hardly changed, and only by mixing the pigment into the liquid material having the hole injection material as a solute, the contrast can be improved even under external light. It becomes possible to provide an organic EL device in which the decrease is suppressed.

  The upper limit value of the wavelength of light blocked by the R hole injection layer 114r is not limited to 550 nm, and the first embodiment also has a preferable effect even at 570 nm, 540 nm, 520 nm, 480 nm, or 460 nm. It is the same. Similarly, the upper limit value of the wavelength of light blocked by the G hole injection layer 114g is not limited to 480 nm, and a favorable effect can be obtained even at 500 nm, 460 nm, 450 nm, or 440 nm as in the first embodiment. It is the same. Further, the upper limit value of the wavelength of light blocked by the B hole injection layer 114b is not limited to 440 nm, and a preferable effect can be obtained if it is in the range of 380 nm to 440 nm, as in the first embodiment. is there.

  Further, the amount of pigment fine particles mixed in each of the hole injection layers 114r, 114g, and 114b is preferably an amount capable of blocking 90% or more of external light that can excite the light emitting layer while transmitting 90% or more of the emitted light. Is the same as that of the first embodiment.

(Fifth embodiment)
FIG. 40 shows an organic EL device according to the fifth embodiment of the present invention. As in the first embodiment, this is a bottom emission type organic EL device in which three types of pixels of R, G, and B are regularly formed. A light shielding layer having a different upper limit of the wavelength of light that can be blocked is formed in each of the pixel regions Ra, Ga, and Ba. Hereinafter, the implementation procedure of this embodiment is demonstrated using FIGS. 1 to 13 according to the first embodiment, FIGS. 16 to 23 according to the second embodiment, FIGS. 24 to 30 according to the third embodiment, and diagrams according to the fourth embodiment. Elements corresponding to those shown in FIGS. 31 to 36 are denoted by the same reference numerals.

  First, as shown in FIG. 37, the TFT 104, the silicon oxide film 106, and the contact hole 108 formed in a matrix are formed on the substrate 102 by the steps shown in FIGS. 1 to 3 of the first embodiment. Then, the R pixel region Ra, the G pixel region Ga, and the B pixel region Ba are determined.

  Next, as shown in FIG. 38, a pigment thin film (hereinafter referred to as a pigment thin film) is formed in a part of each of the pixel regions Ra, Ga, and Ba by a known printing method. Specifically, a process of printing and applying a pigment dispersed in a solvent and removing the solvent by heating is repeated a total of three times for each color to obtain a light-transmitting thin film colored with the pigment. Here, the pigment thin film formed in the R pixel region Ra is referred to as an R pigment thin film 71, the pigment thin film formed in the G pixel region Ga is referred to as a G pigment thin film 72, and the pigment thin film formed in the B pixel region Ba is referred to as a B pigment thin film 73.

  Similar to the ITO thin film formed in the first embodiment, the color of each pigment thin film 71 to 73 varies depending on the color type of the corresponding pixel region. Since the pigment used is the same as the fine particles 11, 12, 13 of each pigment used in the first embodiment, the pigment thin film 71 absorbs light at a wavelength of 550 nm or less, and the pigmented thin film 72 has a wavelength of 480 nm or less. Yellow which absorbs light at a wavelength of yellow, and yellow-green which absorbs light at a wavelength of 440 nm or less.

  Next, a normal (colorless) ITO thin film is formed on the entire surface of the substrate 102 on which the pigment thin films 71 to 73 are formed. Then, the ITO thin film is patterned by photolithography to form pixel electrodes 31, 32, and 33 as shown in FIG. Each pixel electrode 31 to 33 is electrically connected to the TFT 104 through the contact hole 108, and is formed so as to cover each pigment thin film 71 to 73.

Next, as in the first and second embodiments, a lower partition 204 and an upper partition 206 are formed around each pixel region Ra, Ga, Ba, and CF ₄ plasma and O ₂ plasma are performed. A hole injection layer 114 and an organic light emitting layer 116 are formed on the pixel electrodes 31 to 33, a counter electrode 118 and a sealing layer 120 are formed thereon (over the entire surface of the substrate), and the back surface of the substrate 102 (pixel electrode or the like). 40 is attached to the surface on which no is formed, and the organic EL device shown in FIG. 40 is obtained.

  A feature of the present embodiment is that the light-shielding layer (each pigment thin film 71 to 73) does not require conductivity, and therefore the forming material is not limited to ITO or hole injection material. This is because the pixel electrodes 31 to 33 are electrically connected to the TFT 104 without passing through the light shielding layer while the light shielding layer is formed between the pixel electrodes 31 to 33 and the silicon oxide film 106. Therefore, with this configuration, the light shielding layer can be formed by a known technique such as a printing method, and the present invention is almost unchanged, with only an increase in equipment and processes required for printing. The effect of can be obtained.

  The upper limit value of the wavelength of light blocked by the pigment thin film 71 is not limited to 550 nm, and the effect of the present invention can be obtained even at 570 nm, 540 nm, 520 nm, 480 nm, or 460 nm. It is the same. Similarly, the upper limit of the wavelength of light blocked by the pigment thin film 72 is not limited to 480 nm, and the effect of the present invention can be obtained even at 500 nm, 460 nm, 450 nm, or 440 nm, as in the first embodiment. It is. Furthermore, the upper limit value of the wavelength of light blocked by the pigment thin film 73 is not limited to 440 nm, and the effect of the present invention can be obtained as long as it is in the range of 380 nm to 440 nm, as in the first embodiment. .

  Further, the pigment thin films 71 to 73 are preferably formed so as to be able to block 90% or more of external light that can excite each light emitting layer while transmitting 90% or more of the emitted light. It is the same as the form.

(Electronics)
The organic EL device of the present invention is applied to various electronic devices including a display unit. Hereinafter, application examples of an electronic apparatus including the organic EL device of the present invention will be described.

  FIG. 41 is a perspective view showing an example in which the organic EL device of the present invention is applied to a mobile phone. The cellular phone 410 includes the organic EL device of the present invention as a small-sized display unit 411, and includes a plurality of operation buttons 412, an earpiece 413, and a mouthpiece 414.

  In addition to the examples described above, other examples include wristwatches, mobile computers, liquid crystal televisions, viewfinder type and monitor direct view type video tape recorders, car navigation devices, pagers, electronic notebooks, calculators, word processors, workstations. , A video phone, a POS terminal, and a device equipped with a touch panel. The organic EL device of the present invention can also be applied as a display unit of such an electronic device.

(Modification 1)
As a modification of the third embodiment, a form in which the G ₂ colored pixel electrode 52 is not formed is conceivable. That is, the pixel electrode colored only in the R pixel region Ra is formed in the patterning process of the colored ITO thin film formed by sputtering mixed with the pigment. This has the effect that the upper limit of the wavelength of light that can be blocked can be set to an optimum value (for the R light emitting layer). This is because it is not necessary to consider common use with the light emitting layer of G.

(Modification 2)
As a modified example of the third embodiment, a form in which the ITO thin film 202 is formed by sputtering using an ITO target mixed with a pigment having a property of absorbing light having a wavelength of 440 nm or less can be considered. That is, each pixel electrode 31 to 33 is formed of a colored ITO thin film. This provides an effect that a light-shielding layer corresponding to the B light-emitting layer can be obtained, so that it is not necessary to form a UV cut filter, and man-hours and the number of parts can be reduced. Further, when applied to the first modification, the light shielding layer corresponding to the G light emitting layer can also be formed. This is because, as described in the first embodiment, in the G light-emitting layer, even if light having a wavelength of 440 nm or less is blocked, it is effective in improving the contrast.

(Modification 3)
In the third embodiment, a form in which the ITO thin film 202 is formed by sputtering in a low oxygen atmosphere is conceivable. An ITO thin film formed in an atmosphere having a low oxygen concentration of about 1% has a light transmittance of a wavelength of about 400 nm or less as compared with a general ITO thin film formed in an atmosphere having an oxygen concentration of about 3% ( Since it is considerably lower than the ratio of wavelengths exceeding that, it also functions as a light-shielding layer for light of the above wavelengths. Therefore, there is no need to form the UV cut filter 124, and the effect of reducing the number of steps and the number of parts is produced.

(Modification 4)
In the fifth embodiment, a form in which the pixel electrodes 31 to 33 are formed of IZO (indium oxide / lead alloy) is conceivable. Unlike ITO, IZO does not require high-temperature treatment in the process from film formation to electrode formation, and therefore has an effect that a material having low heat resistance such as a resin colored with a dye can be used as a light shielding layer.

(Modification 5)
In the fifth embodiment, the order of the steps may be partially changed to form the contact hole 108 after forming the pigment thin films 71 to 73 on the silicon oxide film 106. Since the surface of the contact hole 108, particularly the bottom, is not contaminated by a process such as printing, there is an effect that the process can be immediately transferred to the process of forming the ITO thin film 202 without performing a process such as cleaning the contact hole 108.

Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 1st Embodiment. The figure which shows an example of the relationship between the wavelength of organic electroluminescent material which produces red light emission, and absorptance. The figure which shows an example of the relationship between the wavelength of organic electroluminescent material which produces green light emission, and absorptance. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 2nd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 3rd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 3rd Embodiment. The figure explaining the sputtering device using the ITO target in which the pigment was mixed. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 3rd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 3rd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 3rd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 3rd Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 4th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 4th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 4th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 4th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 4th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 4th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 5th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 5th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 5th Embodiment. Sectional drawing explaining the manufacturing method of the organic electroluminescence display which concerns on 5th Embodiment. 1 is a perspective configuration diagram illustrating an example of an electronic apparatus including an organic EL device according to the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Pigment particulate, 12 ... Pigment particulate, 13 ... Pigment particulate, 14 ... Pigment particulate, 21 ... R colored pixel electrode, 22 ... G colored pixel electrode, 23 ... B colored pixel electrode, 31 ... R pixel electrode , 32 ... G pixel electrode, 33 ... B pixel electrode, 41 ... R colored pixel electrode, 42 ... G colored pixel electrode, 51 ... G ₂ colored pixel electrode, 52 ... G ₂ colored pixel electrode, 71 ... R pigment film, 72 ... G pigment thin film, 73 ... B pigment thin film, 102 ... transparent substrate, 104 ... TFT, 106 ... silicon oxide film as an interlayer insulating film, 108 ... contact hole, 110 ... polyimide film, 112 ... partition, 114 ... positive Hole injection layer, 114r ... R hole injection layer, 114g ... G hole injection layer, 114b ... B hole injection layer, 116 ... light emitting layer, 118 ... counter electrode, 120 ... sealing layer, 122 ... circularly polarizing plate, 124 ... UV cut fill , 130 ... inkjet device nozzle, 202 ... ITO thin film, 204 ... lower partition, 206 ... upper partition, 300 ... ITO target, 302 ... colored ITO thin film, 303 ... high vacuum chamber, 304 ... anode, 306 ... cathode, 308 DESCRIPTION OF SYMBOLS: Magnet, 410: Mobile phone, 411: Display unit, 412 ... Operation button, 413 ... Earpiece, 414 ... Mouthpiece, C ... Hole liquid material, D ... EL liquid material, Pr ... Fine particles 11 of pigment are dispersed Hole injection material liquid material, Pg... Hole injection material liquid material in which pigment fine particles 12 are dispersed, Pb... Hole injection material liquid material in which pigment fine particles 13 are dispersed, Ra... R pixel Region, Ga ... G pixel region, Ba ... B pixel region, Sr ... ITO sol in which pigment fine particles 11 are dispersed, Sg ... ITO sol in which pigment fine particles 12 are dispersed, Sb ... pigment fine particles 13 Sol of the dispersed ITO.

Claims (15)

Pixel electrodes arranged in a matrix on the substrate;
A counter electrode facing the pixel electrode;
Three types of organic light-emitting layers that exist between the pixel electrode and the counter electrode and emit red, green, and blue for each pixel electrode,
An organic EL device having
Among the organic light emitting layers, a light shielding layer that absorbs light having a wavelength capable of exciting the organic light emitting layer of at least one type is provided between the organic light emitting layer and the display surface. Organic EL device.   The light shielding layer is capable of blocking light having an upper limit within a range of 440 nm to 570 nm and having a wavelength shorter than the upper limit, and the light shielding layer is formed between an organic light emitting layer emitting red light and a display surface. The organic EL device according to claim 1, wherein:   Between the organic light emitting layer that emits red light and the display surface, a light shielding layer that has an upper limit in the range of 440 nm to 570 nm and that can block light of the wavelength below the upper limit is formed, and organic light emission that emits green light 2. The organic material according to claim 1, wherein a light-shielding layer capable of blocking light having a wavelength equal to or lower than the upper limit within a range of 440 nm to 500 nm is formed between the layer and the display surface. EL device.   The light-shielding layer can block light having an upper limit within a range of 440 nm to 500 nm and having a wavelength equal to or shorter than the upper limit, and the light-shielding layer has a green color between an organic light-emitting layer that emits red and a display surface. The organic EL device according to claim 1, wherein the organic EL device is formed between an organic light emitting layer that emits light and a display surface.   The organic EL according to any one of claims 2 to 4, wherein the display surface includes a film that blocks light having a wavelength equal to or shorter than the upper limit, the upper limit being in a range of 380 nm to less than 440 nm. apparatus.   5. The light-shielding layer capable of blocking light having an upper limit of a wavelength of 440 nm or less is formed between the organic light-emitting layer that emits blue light and the display surface. The organic EL device described in 1.   The organic EL device according to claim 1, wherein the light shielding layer also serves as the pixel electrode.   2. The organic EL device according to claim 1, wherein a hole injection layer is provided between the pixel electrode and the organic light emitting layer, and the light shielding layer also serves as the hole injection layer. .   The light shielding layer is obtained by mixing a transparent material having conductivity with a pigment or dye having a property of absorbing light having an upper limit of a predetermined wavelength. 9. The organic EL device according to any one of 8 above.   The light shielding layer is formed between the pixel electrode and a switching element that controls the pixel electrode, and the pixel electrode and the switching element are electrically connected without passing through the light shielding layer. The organic EL device according to claim 1.   The organic EL device according to claim 1, further comprising a circularly polarizing plate on the display surface.   An electronic apparatus comprising the organic EL device according to claim 1. Forming a pixel electrode on the substrate;
Forming three types of organic light emitting layers for emitting red, green and blue on the pixel electrode,
A method of manufacturing an organic EL device having
Among the pixel electrodes, the pixel electrode laminated with at least one type of organic light emitting layer is formed by dropping an ITO solution mixed with a pigment by an ink jet method and then curing the organic material. Manufacturing method of EL device. Forming a pixel electrode on the substrate;
Forming a hole injection layer on the pixel electrode;
Forming three types of organic light emitting layers for emitting red, green and blue on the hole injection layer,
A method of manufacturing an organic EL device having
Among the hole injection layers, the hole injection layer laminated with at least one type of organic light emitting layer is mixed with a pigment, and a liquid material having a hole injection material as a solute is dropped by an inkjet method, A method for producing an organic EL device, wherein the organic EL device is formed by curing. Forming a pixel electrode on the substrate;
Forming three types of organic light emitting layers for emitting red, green and blue on the pixel electrode,
A method of manufacturing an organic EL device having
A method of manufacturing an organic EL device, wherein the pixel electrode laminated with at least one type of organic light emitting layer among the pixel electrodes is formed by a sputtering method using ITO mixed with a pigment as a target. .

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