JP2005292700A - Electroluminescence display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescence display device in which high contrast and little fluctuation in voltage is realized by increasing the efficiency of light taking-out, and consequently high definition and little fluctuation in light emission efficiency is realized. <P>SOLUTION: The organic electroluminescence display device includes: a stainless steel substrate 201; a diamond-like carbon insulating film 102 on the substrate 201; and, on the insulating film 102, a driving TFT part 103 provided with a source electrode and a drain electrode, and a white light emission layer 113 which is placed between a cathode 112 and an anode 114 and comprises a red light emission layer 121, a green light emission layer 122, and a blue light emission layer 123, and intensities of light emission of respective light emission layers are adjusted by hole transport layers 224-1 and 324-1, and light from the white light emission layer 113 is emitted to the outside through the ITO anode 114 and a color filter 116 provided with stainless steel black stripes 117. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electroluminescence (EL) display device and a manufacturing method. In particular, with a single drive voltage, by improving light extraction efficiency, improving chromaticity characteristics with a high-definition display unit, reducing power consumption, improving lifespan, and providing drive TFTs suitable for high-intensity and high-speed display The present invention relates to an organic electroluminescence display device capable of obtaining full-color light emission suitable for a monitor, a TV, and the like and having high productivity, and a manufacturing method.

  In recent years, an electroluminescence driving display element having a plurality of light emitting layers having different wavelengths has been devised. FIG. 4 shows the same structure as FIG. 1 shown in Japanese Patent Laid-Open No. 2002-164170. An anode 1 is formed by sputtering ITO (indium-tin oxide) on a transparent glass substrate 10 having a thickness of 0.7 mm, and a hole transport layer 11 is formed on the ITO anode 1 by a vacuum deposition apparatus. On the hole transport layer 11, the host layer “DPVBi” is doped with 1% by mass of the dopant “BCzVBi” to form an organic light emitting material 3 a of a blue light emitting layer, on which “Alq3” is evaporated to form an electron. The transport layer 12 is formed, and the cathode 2 is formed. Similarly, the host layer “Alq3” doped with 1% by mass of the dopant “Coumarin 6” is vapor-deposited on the hole transport layer 11 to form the organic light-emitting material 3b that emits green light. “Alq3” is deposited thereon to form the electron transport layer 12, and the cathode 2 is formed. Further, after the hole transport layer 11 is formed, a red light emitting material 3c is formed by vapor-depositing the host layer “Alq3” doped with 1% by mass of the dopant “DCJTB”. An example in which the electron transport layer 12 is formed by depositing “Alq3” thereon and the cathode 2 is formed is shown. However, since each pixel is formed in a stripe shape, full color electroluminescence of blue + green + red type is shown. There was a problem that the display part became large.

Further, as a method for driving the electroluminescence display, an active matrix driving method using a thin film transistor (TFT) is attracting attention as a high image quality driving method. In a liquid crystal display (LCD), an image drive element and a signal storage element (pixel capacitance) are integrated into each pixel arranged in a matrix, and each pixel performs one type of storage operation to drive the liquid crystal quasi-statically. It is similar to the method to do. When a large screen is formed using the above thin film transistor, there is a problem that 1) the power supply voltage varies due to the resistance variation of the wiring pattern. 2) There is a problem in that brightness unevenness and color unevenness occur due to variations in on-current and off-current of the driving TFT. 3) There was a problem that there was a variation in luminous efficiency, a current variation, and a lifetime variation due to variations in manufacturing of the electroluminescence element. 4) Due to the difference in thermal expansion coefficient between the substrate and the mask layer, there was a defect that the display position accuracy deteriorated when forming a large screen. 5) When a thin roll substrate is used When the display device is completed, there is a defect that warping occurs due to a difference in coefficient of thermal expansion of the constituent members. 7) Since the conventional substrate is made of glass, it has the disadvantages of poor heat dissipation, impact resistance and drop characteristics. 8) Conventionally, since the substrate is made of glass, it takes time to move it in and out of the magazine, and there is a disadvantage that continuous production cannot be performed. 9) Conventionally, there has been a drawback that the position of the window portion where the black stripe is formed is difficult to improve the contrast, and the displacement becomes larger as the screen becomes larger. 10) There was a problem that the flatness of the substrate was so difficult that it became a large screen. 11) Conventionally, when a thin film transistor (TFT) driving unit is formed on a substrate, an electroluminescent light emitting element layer is formed thereon, an anode is formed below the electroluminescent light emitting element layer, and a cathode is formed above, The upper cathode “Al” reflects light downward and emits light from the substrate side, but there is a problem that light is shielded by the thin film transistor driving unit on the substrate. 12) Also, a thin film transistor driver is formed on the substrate, an electroluminescent light emitting element layer is formed thereon, an anode is formed below the electroluminescent light emitting element layer, and a cathode is formed above the light emitting element on the opposite side of the substrate. In order to emit the light, the anode has to be made of metal and the cathode has to be light transmissive, so that there has been a problem that a special electrode material has to be used.
JP 2002-164170 A

  The present invention solves the above problems, and there is no displacement or warping due to thermal expansion in the display portion during formation of a large screen display device, and light extraction efficiency is increased by extracting light through the anode. Improvement of power supply voltage variation by contrast and anode resistance reduction, white electroluminescence display part formed by multiple light emitting layers, high output by electron and hole movement efficiency, whiteness improvement, high definition , Improved luminous efficiency variation, current variation, life variation variation, and improved on-current / off-current variation of driving TFTs to improve brightness unevenness, color unevenness, impact resistance, drop characteristics, suitable for high-speed display Another object of the present invention is to provide an organic electroluminescence display device.

  The electroluminescence display device according to the present invention comprises a driving thin film transistor portion having a source electrode and a drain electrode on a substrate, and a light emitting element layer sandwiched between both the cathode and anode electrodes. And the electroluminescence display part is driven by the driving thin film transistor part, and light from the electroluminescence display part is emitted to the outside through an anode.

  The electroluminescence display device according to the present invention comprises an insulating layer on a substrate, a driving thin film transistor portion having a source electrode and a drain electrode, and a light emitting element layer sandwiched between both the cathode and anode electrodes. And an electroluminescence display portion are formed in order, the electroluminescence display portion is driven by the driving thin film transistor portion, and light from the electroluminescence display portion is emitted to the outside through the anode. Features.

  The electroluminescent display device is characterized in that a color filter layer is formed on the anode.

  The electroluminescent display device is characterized in that a black stripe made of a metal layer is formed on the anode.

  The electroluminescence display device is characterized in that the black stripe made of the metal layer is formed of stainless steel.

  The electroluminescence display device is characterized in that the electroluminescence display portion is composed of an electron transport layer, first and second light emitting layers, and first and second hole transport layers between a cathode and an anode. To do.

  In the electroluminescence display device, the electroluminescence display section includes an electron transport layer, a first light emitting layer, a first hole transport layer having a width smaller than that of the first light emitting layer, and a second layer between the cathode and the anode. And a second hole transport layer.

  In the electroluminescence display device, the electroluminescence display section includes an electron transport layer between the cathode and the anode, first, second, and third light emitting layers, and first, second, and third hole transport layers. It is characterized by comprising.

  In the electroluminescence display device, the electroluminescence display section includes an electron transport layer, a first light emitting layer, a first hole transport layer having a width smaller than that of the first light emitting layer, and a second layer between the cathode and the anode. The light-emitting layer comprises a second hole transport layer, a third light-emitting layer, and a third hole transport layer that are narrower than the second light-emitting layer.

  The electroluminescence display device is characterized in that the light quantity of the light emitting layer is adjusted by changing the width of the transport layer sandwiched between the light emitting layers.

  The electroluminescent display device is characterized in that a transport layer sandwiched between the light emitting layers is formed in a comb shape and a mesh shape.

  The electroluminescent display device is characterized in that the light emitting layers have different emission spectra.

  The electroluminescent display device is characterized in that the emission color is white light by the combination of the light emitting layers.

  As described above in detail, according to the organic electroluminescence display device of the present invention, a plurality of light emitting layers are formed in layers to enable high definition and continuous production, and a light emitting layer between these light emitting layers. Inserting a transport layer that is the same as the width of the light emitting layer or narrower than the width of the light emitting layer improves the recombination rate of electrons and holes, and increases the light extraction efficiency by extracting light from the anode formed on the top of the display section. The black stripe and color filter layer made of stainless steel formed on the anode improve the contrast and reduce the wiring resistance, improve the power supply voltage variation, reduce the influence of external light, improve the warp, and improve the display position. By forming an amorphous silicon film active layer formed on the insulating layer, the output of the drive circuit is improved, the chromaticity characteristics are improved, the life is improved, and the power consumption is improved. Reduced high intensity to emit light in a single driving voltage with becomes possible, the impact resistance, the organic electroluminescent display device having excellent drop characteristics, and it is possible to provide a manufacturing method thereof.

  Hereinafter, details of the present invention will be described with reference to the drawings. FIG. 1A is a schematic diagram showing a basic configuration of an organic electroluminescence (EL) display device 115 according to the first embodiment of the present invention. In FIG. 1A, a driving TFT portion 103, an Al cathode 112, a white light emitting element layer 113, and an ITO anode 114 are formed on a glass substrate 101. FIG. 1B is a schematic diagram showing a basic configuration of an organic electroluminescence display device 215 according to the second embodiment of the present invention. In FIG. 1B, the insulating layer 102 and the insulating layer 102 are formed on the stainless steel substrate 201 in the same manner as in FIG. In more detail, FIG. 2A shows a schematic diagram of the driving TFT portion 103 and the white light emitting layer 113. The driving TFT portion 103 is formed on a 0.7 mm glass substrate 101 in FIG. 1A, and the top of the glass substrate 101 is the same as the upper portion of the insulating layer 102 in FIG. The description will be made with reference to FIG. In FIG. 1B, diamond-like carbon (DLC) coating is performed on the 0.7 mm stainless steel substrate 201 as the insulating layer 102. This DLC film is formed by an ion vapor deposition method, a high frequency discharge plasma CVD method, or the like.

  In the driving TFT section 103 of FIG. 2A, hydrogen is added on the insulating layer 102 by plasma CVD using thermal decomposition of monosilane (SiH 4) or disilane (Si 2 H 6) at a processing temperature of about 300 ° C. Thus, the reaction is promoted to form an amorphous silicon film active layer 104 (film thickness of 500 mm). A gate insulating layer 109 is formed on the amorphous silicon film active layer 104 with a thickness of 1000 mm by a silicon oxide film by a CVD method. A gate electrode 110 is formed on the gate insulating layer 109 by patterning into a predetermined shape. The gate electrode 110 is formed using a CVD method. Impurity implantation and activation without providing a special heat treatment process by irradiating an ion shower with a mixed gas of phosphine gas (PH3) or diborane gas (B2H6) with hydrogen gas using the gate electrode 110 as a mask by self-alignment technology Simultaneously, the drain region 106 and the source region 105 are formed on the amorphous silicon film active layer 104. The drain contact hole 106a of the drain region portion 106 and the gate insulating layer 109 is formed, and the drain electrode 108 made of an aluminum metal is formed. An interlayer insulating film 111 is formed on the entire surface of the device using a silicon oxide film by a CVD method. A source contact hole 105a in contact with the source region 105 is formed in the interlayer insulating layer 111, and the source electrode 107 is connected to the cathode 112 of the organic electroluminescence display portion by the source contact hole 105a made of an aluminum metal. Note that the gate insulating film 109 and the interlayer insulating film 111 may be formed by DLC coating in the same manner as the insulating layer 102. The cathode 112 is formed by depositing “Al” on the interlayer insulating layer 111 to a thickness of 1500 mm.

  In the white light emitting element layer 113 of FIG. 2A, lithium fluoride “LiF” is deposited on the cathode 112 to a thickness of 5 mm, and LUMO 2.85 eV, HOMO 5.62 eV, energy band gap 2. The electron transport layer 120 is formed by evaporating 200 e of 77 eV of “Alq3”. Then, a host layer “Alq3” on the electron transport layer 120 is doped with 1 wt% of a red dopant “DCJTB” to form a red light emitting layer 121 by vapor deposition with a thickness of 200 mm. “NBP” is deposited on the red light-emitting layer 121 to a thickness of 400 mm using a mask to form a hole transport layer (224-1) having LUMO of 2.45 eV, HOMO of 5.46 eV, and an energy band gap of 3.0 eV.

  On the hole transport layer (224-1), a green light emitting layer 122 in which the host layer “Alq3” is doped with 1 wt% of the green dopant “Coumarin 6” is formed by vapor deposition of 500 μm. On the green light emitting layer 122, “NBP” is deposited to a thickness of 400 mm using a mask to form a hole transport layer (324-1).

  On the hole transport layer (324-1), a host layer “BAlq” with LUMO 2.6 eV, HOMO 5.3 eV, and energy band gap 2.7 eV is doped with 1% by weight of dopant “Perylene” to a thickness of 500 mm. Thus, the blue light emitting layer 123 is formed of the blue light emitting organic light emitting material. On the blue light-emitting layer 123, “NBP” is deposited to a thickness of 400 to form a hole transport layer 124 having LUMO 2.45 eV, HOMO 5.46 eV, and energy band gap 3.0 eV.

  Next, “CuPc” is deposited to a thickness of 20 nm on the hole transport layer 124 to form the anode 114 on the “CuPc”. When a positive voltage is applied to the anode 114 and a negative voltage is applied to the cathode 112, electrons injected into the light emitting layer 113 through the electron transport layer 120 and holes injected through the hole transport layer 124 are contained in the light emitting layer 113 or the light emitting layer. The light is emitted by recombination at the interface between 113 and the hole transport layer 124.

  Here, in the white electroluminescent light emitting layer 113 of the present invention, the LUMO band gap energy difference between the host layer of the light emitting layer and the dopant is 0.3 eV or more in the light emitting portions 121, 122, 123 formed in three layers. The layer emits light. Further, the hole transport layer is sandwiched between the three host layers. Each light-emitting layer is formed of two organic layers, “Alq3” with a hole transport layer (224-1) interposed therebetween, and further “BAlq” with a hole transport layer (324-1) and each organic material. It is characterized by. Since the hole transport layers (224-1) and (324-1) pass holes and do not allow electrons to pass through, the opening of the hole transport layer (224-1) moves upward, but the hole transport layer (224-1) Then the electrons are stopped. Since the holes pass through the hole transport layer (224-1) to the cathode 112, the electrons from the cathode 112 and the holes that have passed through the hole transport layer (224-1) are recombined at the bottom of the hole transport layer (224-1). The red light emitting layer 121 emits red light below the hole transport layer (224-1).

  Since the hole transport layer (324-1) does not pass electrons injected from the cathode 112, the electrons move upward in the opening of the hole transport layer (324-1). Since the hole transport layer (324-1) allows holes injected from the cathode 114 to pass therethrough, the green light emitting layer 122 emits green light at the opening of the hole transport layer (214-1) and below the hole transport layer (324-1). . Electrons injected from the cathode 112 in the openings of the hole transport layers (224-1) and (314-1) travel toward the anode 114. The holes injected from the anode 114 and the blue light emitting layer 123 or the hole transport layer 124 are recombined to emit blue light. The light emitting layer has a spectrum different from each other and is mixed by red, green, and blue light emission to form a white light emitting layer 113 having a high output that is about twice as high as that of a single color. Since the white light-emitting layer 113 is formed of three layers with the hole transport layer (224-1) and the hole transport layer (324-1) interposed therebetween, the same amount of light can be obtained with about half of the conventional current. Further, by forming the three layers in an overlapping manner, the variation in the luminous efficiency due to the decrease in the variation in the film thickness compared with the variation in the film thickness of the single-layer electroluminescent element is improved, and the current consumption is halved. Life variation can be improved by reducing current consumption and current consumption by half. Compared to a white element obtained by emitting blue, green, and red light separately, the driving voltage can be a single voltage because the three layers are overlapped. Therefore, driving is easier and the circuit can be omitted compared to the conventional FIG.

  Also, since it has three layers compared to the white element obtained by emitting blue, green, and red separately in FIG. 4, it can have a light emission area of 1/3, and it emits solid light instead of the stripe light emission shown in FIG. For example, since it is not necessary to set the light emission width to 0.5 mm and the pitch to 0.5 mm, the light emission area can be halved. By combining these, the same amount of light emission can be obtained with an area of 1/6, so that high definition and high luminance can be achieved.

  Furthermore, another embodiment of the white light emitting layer 113 in the present invention is shown in FIG. The portion below the electron transport layer 120 is the same as FIG. On the electron transport layer 120, LUMO 2.85 eV, HOMO 5.62 eV, host layer “Alq3” with an energy band gap of 2.77 eV, LUMO 3.11, HOMO 5.26 eV, dopant “DCM2” with an energy band gap of 2.65 eV are added. The orange layer 221 is formed by evaporating by weight%. Using a mask, “NBP” is deposited to a thickness of 400 mm on “DCM2” on the orange layer 221 to form a hole transport layer (424-1). A blue-green layer 222 is formed by depositing a host layer “Alq3” doped with 1 wt% dopant “CuPc copper phthalocyanine” on the hole transport layer (424-1) in a thickness of 500 mm. A hole transport layer 124 is formed on the blue-green layer 222 in the same manner as in FIG. The portion above the hole transport layer 124 is the same as that shown in FIG.

  Here, in the white electroluminescence light-emitting layer 213 of the organic electroluminescence display device 415 according to the fourth embodiment of the present invention, the orange layer 221 and the blue-green layer 222 formed in two layers, Since the LUMO band gap energy difference between the host layer and the dopant is 0.3 eV or less, the present invention is characterized in that both the host layer and the dopant layer emit light. That is, in terms of spectrum, blue by “CuPc”, green by “Alq3”, combined blue-green layer 222, green by “Alq3” across the hole transport layer (424-1), red by “DCJTB”, and orange 221 Since these are mixed, the whiteness can be improved in a well-balanced manner.

  Furthermore, since each light emitting layer has a common host layer of “Alq3”, the same material can be used and productivity is good. In addition, the light emitting layer has a spectrum different from each other, and the hole transport layer is interposed between the light emitting layers, so that the movement of the holes becomes efficient, and the white light emitting layer 213 having a high output of about twice is formed by the orange and blue green light emitting colors. Since the white light emitting layer 213 is formed of two layers, the same amount of light can be obtained with half the current. In addition, by forming two layers, the film thickness variation can be improved compared to the film thickness variation of a single-layer electroluminescent element, and the variation can be reduced. Thus, the current variation is improved, and the life variation is improved by reducing the current consumption by half. The driving voltage may be a single voltage as compared with the white element shown in FIG. 4 obtained by emitting blue, green, and red separately, so that the driving is easier and the circuit can be omitted than in the conventional FIG.

  In addition, compared with the white element obtained by individually emitting blue, green, and red shown in FIG. 4, two layers are stacked with the hole transport layer (424-1) interposed therebetween, so that the emission area can be reduced to 1/3. The light emission area can be halved since it is not necessary to set the light emission width to 0.5 mm and the pitch to 0.5 mm, for example, because the light is emitted solidly instead of the stripe-shaped light emission shown in FIG. By combining these, the same amount of light emission can be obtained with an area of 1/6, so that high definition and high luminance can be achieved.

  3A and 3B show another example of the white light emitting layer 113 shown in FIGS. 1A and 1B. FIG. 3A shows a white electroluminescent light emitting layer 313 of an organic electroluminescence display 515 which is another embodiment according to the present invention. A hole transport layer (224-2) narrower than the width of each light-emitting layer between the light-emitting layers (red light-emitting layer 121, green light-emitting layer 122, and blue light-emitting layer 123) of the white light-emitting layer 113 in FIG. The layer (324-2) is sandwiched between them. The hole transport layer (224-2) and the hole transport layer (324-2) are narrower than the width of each light emitting layer using a mask, and the hole transport layer (224-2) has an opening at the center and “NBP” of 400 mm. It is formed by vapor deposition. Since each of the light emitting layers 121 and 122 is a host layer “Alq3” and the light emitting layer 123 is a host layer “BAlq”, the movement of holes becomes more efficient.

  In FIG. 3A, since the hole transport layer (224-2) does not pass electrons through holes, electrons injected from the cathode 112 and the anode 114 are injected below the hole transport layer (224-2). The holes recombine and the blue light emitting layer 121 emits blue light. In the hole transport (224-2) opening, since electrons pass, holes and electrons recombine above the opening of the hole transport layer (224-2) and below the hole transport layer (424-2), and green. The light emitting layer 122 emits green light. Since electrons are stopped by the hole transport layer (324-2), electrons pass outside the hole transport layer (324-2), and the red light-emitting layer 123 or the red light-emitting layer 123 emits red light at the interface of the hole transport layer 124. To do.

  The light quantity of a light emitting layer is controllable by the width | variety of a hole transport layer (224-2) and (324-2). Thereby, the whiteness of the white light emitting layer 313 can be adjusted. In addition, the hole transport layer (224-2) and the hole transport layer (324-2) may be comb-shaped or mesh-shaped, their upper and lower positions may be aligned, or may be alternately shifted.

  In FIG. 3B, a hole transport layer (424-2) narrower than the width of the light emitting layer is sandwiched between the light emitting layers (orange light emitting layer 221 and blue green light emitting layer 222) of the white light emitting layer 213 in FIG. 2B. It is a thing. The hole transport layer (424-2) is formed by depositing 400 nm of "NBP" having an opening at the center narrower than the width of the light emitting layer using a mask. The host layers of the orange light-emitting layer 221 and the blue-green light-emitting layer 222 are “Alq3”, and the movement of holes is made efficient by sandwiching the hole transport layer (424-2).

  In FIG. 3B, since the hole transport layer (424-2) does not pass electrons through the holes, the electrons injected from the cathode 112 and the holes injected from the anode 114 are below the hole transport layer (424-2). It recombines with the orange light emitting layer 221 through the hole transport layer (424-2) and emits orange light. Since electrons pass through the opening of the hole transport (424-2), electrons injected from the cathode 112 recombine with the blue-green light emitting layer 222, or electrons and holes recombine at the interface of the hole transport layer 124. Emits blue-green light.

  The light amount of the light emitting layer can be controlled by the width of the hole transport layer (424-2). Thereby, the whiteness of the white light emitting layer 413 can be adjusted. The hole transport layer (424-2) may be comb-shaped or mesh-shaped.

In the electroluminescence display driving TFT section 103 according to the present invention, the current consumption of the white light emitting layers 113, 213, 313, 413 may be about ½, so that the current of 10 mA / cm ² is 5 mA / cm ² . Since the same amount of light emission can be obtained, the amorphous silicon film active layer 104 shown in FIGS. 2 (a), 2 (b), 3 (a), and 3 (b) reduces the on-current. In addition, since the white light emitting layers 113, 213, 313, and 413 can be driven sufficiently, luminance unevenness and color unevenness are eliminated, and high-speed display is possible. Since the thin film transistor (TFT) driving portion 103 can be formed of the amorphous silicon film active layer 104, the cost can be reduced by reducing the number of steps.

  2 (a), 2 (b), 3 (a), and 3 (b), an anode 114 made of an ITO film is vacuum-deposited on the hole transport layer 124, and ITO with 10% SnO2 is heated and evaporated with an electron gun. To a film thickness of about 0.4 μm. An ITO film having a thickness of 300 nm is formed on the ITO film by a sputtering apparatus. In the embodiment of the present invention, the anode 114 and the cathode 112 are formed of the same material as that of the prior art, so that it is not necessary to use a special electrode material. In addition, since light from the light emitting layers 113, 213, 313, and 413 is extracted to the outside through the anode 114, light is not absorbed by the driving TFT portion 103, so that the efficiency of external extraction of light is increased. Further, the ITO anode 114 is excellent in mechanical strength, and is characterized in that the electroluminescence display portions 113, 213, 313, and 413 are hardly deteriorated even in a high temperature and high humidity environment.

  Further, by forming an anode 114 made of this ITO film, stainless steel is used in the electroluminescence display devices 315, 415, 515, and 615 shown in FIGS. 2 (a), 2 (b), 3 (a), and 3 (b). Since the black stripe 117 formed by vapor deposition is formed on the anode 114, the conductivity of the ITO film anode 114 is improved and the resistance is lowered, thereby improving the power supply voltage variation due to the resistance variation of the wiring pattern. There is a feature.

  In the electroluminescent display devices 315, 415, 515, and 615 of FIGS. 2 (a), 2 (b), 3 (a), and 3 (b), the substrate 201 is formed on the lower portion and formed on the upper portion. In addition, since the black stripes 117 are all made of metal stainless steel, the coefficient of thermal expansion is the same as that of the lower ones. Therefore, the display devices 315, 415, 515, and 615 are characterized by no increase in strength and no warping. In order to form black stripes 117 by depositing stainless steel on the anode 114, the light extraction portion 116 that has passed through the anode 114 is formed by photoresist coating, exposure, and etching, but an etching mask is formed of stainless steel. As a result, the same thermal expansion coefficient is obtained with the same material as the substrate 201 and the black stripe 117, so that there is no displacement of each light emitting portion after etching, and a display device with high display accuracy can be obtained when forming a large screen. is there.

  Further, for the same reason as described above, vapor deposition is performed on the anode 114 in the electroluminescence display devices 315, 415, 515, and 615 shown in FIGS. 2 (a), 2 (b), 3 (a), and 3 (b). The alignment of the window 116 of the black stripe 117 formed by etching the formed stainless steel can be facilitated. Blue, green and red color filters 216 are formed in the window 116. The color filter 216 is formed by an ink jet method or a printing method. A protective layer 118 such as an antireflection film is attached on the color filter 216 and the black stripe 117. Here, since the electroluminescent light emitting layers 113, 213, 313, and 413 do not emit light due to external light, the contrast can be improved together with the effect of the black stripe 117.

  As another example of the driving TFT unit 103 shown in FIGS. 2A, 2B, 3A, and 3B, monosilane (on the insulating layer 102 is formed by plasma CVD). Hydrogen is added at a processing temperature of about 300 ° C. using thermal decomposition of SiH 4) or disilane (Si 2 H 6) to promote the reaction, thereby forming an amorphous silicon film active layer 104 (thickness 500 mm). Further, the polycrystalline silicon film active layer 204 (not shown) can be formed by melt recrystallization or solid phase growth of the amorphous silicon film active layer 104. Specifically, by irradiating the amorphous silicon film active layer 104 with laser light by a laser annealing method, the melt recrystallization method heats and melts only the surface of the amorphous silicon film active layer 104 to perform recrystallization. This is a method of keeping the temperature of the substrate 201 at 600 ° C. or lower while achieving the temperature. The solid phase growth method is a method in which only the surface of the amorphous silicon film active layer 104 is heated to a temperature that does not lead to melting, and the temperature of the substrate 201 is maintained at 600 ° C. or lower while recrystallization is performed in the solid phase. . As the heating method, an energy beam such as lamp light, laser light, or electron beam is irradiated.

In the driving TFT 203 (not shown) on which the low-temperature polycrystalline silicon film active layer 304 is formed, the electron mobility is 100 to 300 cm ² / Vs, so that the driver IC 119 can be formed on the stainless steel substrate 201 and the insulating layer 102. Therefore, the wiring connecting the driving TFT and the driver IC can be largely omitted.

Furthermore, a single crystal silicon film active layer 304 (not shown) is formed on the insulating layer 102 at an epitaxial growth temperature of 700 to 800 ° C. by using MOCVD or the like. Since the single-crystal silicon driving TFT 303 (not shown) has an electron mobility of 1000 cm ² / Vs, a driver IC 119, a monitor driving circuit, a color TV circuit, and the like can be formed over the stainless steel substrate 201 and the insulating layer 102. Wiring can be greatly omitted, and the display devices 315, 415, 515, and 615 can be thinned, production efficiency can be improved, and cost can be reduced.

Here, the formal names of the materials described by the above names are as follows.
“NBP”... N, N′-Di ((naphthalene-1-yl) -N,
N'-diphenyl-benzidine)
"Alq3" Tris (8-hydroxyquinolinato)
aluminum
“DCJTB”... (2- (1,1-Dimethylethyl) -6- (2- (2,3,6,7-tetrahydro-1,1,7,7-tertylmethyl-1H, 5H-benzo [ij] quinolizin-9-yl) ethenyl) -4H-pyran-4-ylidene) preparedintrile.
“Coumarin 6”... 3- (2-Benzothiazolyl) -7- (diethylamino) coumarin.
“BAlq”... (1,1′-Bisphenyl-4-Olato) bis (2-methyl-8-quinolineplate-N1,08) Aluminum.
In addition, this invention is not limited to the said embodiment, A various deformation | transformation is possible based on the meaning of this invention, and they are not excluded from the scope of the present invention.

  Although an n-type TFT has been described in the present invention, a p-type TFT may be used.

  In addition, as an example of the active layer of the drive layer, an example of an amorphous silicon film, a polycrystalline silicon film, and a single crystal silicon film has been shown.

  In the present invention, a stainless steel substrate has been described as the substrate, but a glass substrate or a plastic substrate may be used as shown in FIG.

  In the present invention, the DLC film is used as the insulating layer. However, since the DLC film has a good flatness, a low-priced plastic substrate or glass substrate having a poor surface flatness is used to reduce the overall price. Also good.

  In the present invention, an example of the hole transport layer is shown as a transport layer having the same width as the light-emitting layer inserted between the light-emitting layers and / or a width narrower than the light-emitting layer, but the electron transport layer and the hole transport are adapted to the characteristics of the host layer. A layer and an electron transport layer may be mixed.

  In the present invention, the three-layer and two-layer white light emitting portions have been described. However, by stacking n layers as white units, the driving current becomes 1 / 2n, so that the consumption current and the consumption power can be reduced.

  Further, since the substrate of the present invention is made of metal or plastic and has a strong structure against bending, it can be bent so that the display surface can be seen at an angle of 180 ° or more.

Further, after forming the display device using the substrate of the present invention as a thin film metal, it may be bonded to a plastic base material.

1 is a schematic view of an electroluminescence display device according to a first embodiment of the present invention. It is the schematic of the electroluminescent display apparatus which is the 2nd Embodiment concerning this invention. It is the schematic of the TFT for a drive of the electroluminescent display apparatus which concerns on this invention, and a white light emitting layer. It is the schematic of the drive TFT and white light emitting layer of the other electroluminescent display apparatus which concerns on this invention. It is the schematic of the white light emitting layer in the other electroluminescent display apparatus which concerns on this invention. It is the schematic of the white light emitting layer in the other electroluminescent display apparatus which concerns on this invention. It is the schematic of the conventional electroluminescent element.

Explanation of symbols

201 Substrate 102 Insulating layer 103 Driving TFT portion 107 Source electrode 108 Drain electrode 109 Gate insulating layer 110 Gate electrode 112 Cathode 113 White light emitting layer 114 Anode 120 Electron transport layer 121 Red layer 122 Green layer 123 Blue layers 124 and 224-1 224-2, 324-1 Hole transport layer

Claims (13)

  A driving thin film transistor unit having a source electrode and a drain electrode and an electroluminescence display unit composed of a light emitting element layer sandwiched between the cathode and anode electrodes are sequentially formed on the substrate, and the electroluminescence The display unit is driven by the driving thin film transistor unit, and light from the electroluminescence display unit is emitted to the outside through an anode.   An insulating layer is provided on the substrate, and a driving thin film transistor portion provided with a source electrode and a drain electrode, and an electroluminescence display portion formed of a light emitting element layer sandwiched between the cathode and anode electrodes are sequentially formed. The electroluminescence display unit is driven by the driving thin film transistor unit, and light from the electroluminescence display unit is emitted to the outside through an anode.   The electroluminescent display device according to claim 1, wherein a color filter layer is formed on the anode.   4. The electroluminescent display device according to claim 3, wherein a black stripe made of a metal layer is formed on the anode.   The electroluminescent display device according to claim 4, wherein the black stripe made of the metal layer is made of stainless steel.   6. The electroluminescent display unit includes an electron transport layer, first and second light emitting layers, and first and second hole transport layers between a cathode and an anode. An electroluminescent display device according to claim 1.   The electroluminescence display unit includes an electron transport layer, a first light emitting layer, a first hole transport layer having a width smaller than that of the first light emitting layer, a second light emitting layer, and a second hole between the cathode and the anode. It consists of a transport layer, The electroluminescent display apparatus as described in any one of Claims 1-5 characterized by the above-mentioned.   The electroluminescent display unit includes an electron transport layer, first, second, and third light-emitting layers, and first, second, and third hole transport layers between a cathode and an anode. Item 6. The electroluminescent display device according to any one of Items 1 to 5.   The electroluminescence display unit includes an electron transport layer, a first light-emitting layer, a first hole transport layer whose width is narrower than the first light-emitting layer, a second light-emitting layer, and a width between the cathode and the anode. The electroluminescent display device according to claim 1, comprising a second hole transport layer, a third light emitting layer, and a third hole transport layer that are narrower than the light emitting layer.   The electroluminescent display according to any one of claims 6 to 9, wherein the transport layer sandwiched between the plurality of light emitting layers is adjusted in light quantity by changing a width thereof. apparatus.   The electroluminescent display device according to claim 1, wherein the transport layer sandwiched between the light emitting layers is formed in a comb shape and a mesh shape.   The electroluminescent display device according to claim 1, wherein the light emitting layers have emission spectra different from each other. The electroluminescent display device according to any one of claims 1 to 12, wherein an emission color is white light by a combination of the light emitting layers.

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