JP4263474B2 - Method for manufacturing element substrate for display device and transfer body - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a display device element substrate manufacturing method and a transfer body, and more particularly, a display device element substrate manufacturing method including various elements used in a liquid crystal display device or an EL display device, and a manufacturing method thereof. The present invention relates to a transfer body.
[0002]
[Prior art]
In recent years, display devices such as liquid crystal display devices or EL (Electroluminescence) display devices are rapidly expanding their applications to information equipment. In these display devices, an element substrate including various dot matrix elements corresponding to the simple matrix method and the active matrix method is used. As the dot matrix element, a striped transparent electrode is used in the simple matrix system, while an active element such as a TFT (Thin Film Transistor) element or an MIM (Metal Insulator Metal) element is used in the active matrix system.
[0003]
As a base substrate of such an element substrate, there is one using a plastic film instead of a glass substrate for weight reduction or damage prevention. A plastic film has low rigidity and a low thermal deformation temperature, and thus is likely to undergo thermal deformation such as warping and expansion / contraction in a manufacturing process involving heat treatment.
[0004]
For this reason, in a manufacturing method in which a dot matrix element or a color filter layer is directly formed on a plastic film, conditions such as a manufacturing process involving heat treatment are limited, and high-precision alignment becomes difficult. It may be impossible to manufacture an element substrate having
[0005]
In order to avoid such problems, a transfer layer is formed by aligning dot matrix elements and color filter layers with high precision on a glass substrate with high rigidity and high heat resistance without limiting manufacturing conditions. Then, there is a method of forming the transfer layer by transferring it onto a plastic film. More specifically, first, a dot matrix element, a color filter layer, and the like are formed on a glass substrate via a peeling layer and a buffer layer (silicon oxide film or the like) to form a transfer layer. At this time, since the dot matrix element, the color filter layer, and the like are formed on the glass substrate, the formation conditions are not limited and are formed with high precision alignment.
[0006]
Next, after the transfer layer is transferred to a plastic film, the uppermost release layer is removed. The buffer layer under the release layer is formed to protect the dot matrix element and the like from being damaged when the release layer is removed.
[0007]
By using such a transfer technology, the plastic film does not undergo thermal deformation because the manufacturing process involving heat treatment is performed on a glass substrate. Therefore, a color filter layer, a dot matrix element, etc. are formed on the plastic film with desired characteristics. In addition, it can be formed by alignment with high accuracy.
[0008]
For example, Patent Documents 1 to 5 describe a method of manufacturing an element substrate including various elements for a display device by using a technique related to the transfer technique as described above.
[0009]
[Patent Document 1]
JP 2002-189219 A
[Patent Document 2]
JP 2002-116455 A
[Patent Document 3]
JP 2001-356710 A
[Patent Document 4]
JP-A-11-24081
[Patent Document 5]
Japanese Patent Laid-Open No. 10-125931
[0010]
[Problems to be solved by the invention]
In the transfer technique as described above, as a method of removing the release layer after transferring the transfer layer onto the plastic film, ₂ And CF _Four A plasma etching using a mixed gas with or a wet etching such as a high-temperature alkaline solution, or a combination of these is employed.
[0011]
At this time, the etching selectivity (etching rate of the peeling layer / etching rate of the buffer layer) with respect to the underlying buffer layer (silicon oxide film) when the peeling layer (polyimide resin film) is subjected to plasma etching or wet etching is considerably low. For this reason, when the peeling layer is removed, the underlying buffer layer is etched, which may damage the Dod matrix element and the like under the buffer layer.
[0012]
For example, when an element substrate for an active matrix type organic EL display device is manufactured, an organic EL layer is formed on a pixel electrode connected to a TFT element or the like. For this reason, when the pixel electrode is damaged when the peeling layer is removed and unevenness is generated on the surface thereof, the organic EL layer formed on the pixel electrode is formed with uneven thickness. Since organic EL elements are self-emitting, if the thickness varies, defects such as defective light emission are likely to occur.
[0013]
Also, when manufacturing an element substrate for a liquid crystal display device, various elements under the buffer layer may be damaged, and the manufacturing yield may be reduced.
[0014]
O ₂ Although it is possible to increase the above-mentioned etching selectivity by using plasma etching using only the substrate, it is necessary to devise measures such as raising the substrate temperature in order to obtain a practical release layer etch rate. It is extremely difficult to apply to the processing of plastic films with low heat resistance.
[0015]
In Patent Documents 1 to 5 described above, it is described that an element substrate for a display device is manufactured using a transfer technique, but when the release layer is removed, the underlying buffer layer is etched and pulled. No consideration is given to the problem of damaging the various elements below.
[0016]
The present invention was created in view of the above-described problems, and in a method for manufacturing an element substrate for a display device using a transfer technique, a display capable of removing a release layer without causing any problem. It is an object of the present invention to provide a method for manufacturing an element substrate for an apparatus and a transfer member used in the manufacturing method.
[0017]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention relates to a method for manufacturing an element substrate for a display device, the step of forming a release layer made of a resin on the substrate, and the entire surface of the release layer on the substrate. , Resistant to oxygen plasma or aqueous alkali Forming a first buffer layer made of a conductive thin film; forming a second buffer layer made of an inorganic insulating film on the first buffer layer; and at least driving or active on the second buffer layer A step of forming an element layer; peeling from an interface between the substrate and the peeling layer; and on a plastic film through an adhesive layer, in order from the bottom, the driving or active element layer, the second buffer layer, the second buffer layer, A step of transferring and forming one buffer layer and the release layer; a step of removing the release layer using the first buffer layer as a barrier film; and the entire first buffer layer with respect to the second buffer layer And a step of selectively removing.
[0018]
In a preferred aspect of the present invention, first, a peeling layer, a first buffer layer, a second buffer layer, a drive or active element layer, and the like are formed on a substrate (such as a glass substrate) in order from the bottom to form a transfer layer. . Thereafter, the transfer layer is transferred and formed on the plastic film with the transfer layer turned upside down via an adhesive layer. Then the top release layer is for example O ₂ / CF _Four It is removed by plasma using gas or alkaline solution.
[0019]
At this time, O under the release layer ₂ / CF _Four Since the first buffer layer (conductive thin film) resistant to plasma, alkaline solution, etc. is provided, there is no possibility that the second buffer layer (inorganic insulating film) below, the driving or active element layer, etc. are damaged. Subsequently, after the first buffer layer is used as a barrier film for removing the release layer, it is selectively removed with respect to the underlying second buffer layer. The second buffer layer is left on the element substrate as a transparent buffer layer.
[0020]
By doing so, the peeling layer is removed without causing any damage to the second buffer layer or the driving or active element layer, so that the manufacturing yield of the element substrate for display device can be improved. The element substrate for a display device of the present invention is applied to a liquid crystal display device or an EL display device.
[0021]
In one preferable aspect of the present invention, the drive or active element layer is a striped transparent electrode, or an active element and a pixel electrode provided on the active element, and the first buffer layer is removed. Thereafter, a step of forming an opening in a predetermined portion of the second buffer layer on the stripe-shaped transparent electrode or on the pixel electrode provided in the active element, and the stripe-shaped transparent exposed in the opening The display device element substrate includes a step of forming an organic EL layer on an electrode or a pixel electrode provided in the active element, and a step of forming an upper electrode connected to the organic EL layer. It becomes an EL display device.
[0022]
As described above, in the present invention, since the first buffer layer functions as a barrier film in the step of removing the release layer, the lower first buffer layer is etched, or the drive or active element layer is There is no problem of unevenness on the surface due to damage.
[0023]
Therefore, when the driving or active element layer is an active element such as a TFT element or an MIM element and a pixel electrode connected to the active element, the organic EL layer formed on the pixel electrode is formed in a flat state without unevenness in thickness. As a result, the light emission characteristics of the organic EL layer can be improved. The same applies when the element layer is a striped transparent electrode corresponding to the simple matrix type.
[0024]
In order to solve the above-described problems, the present invention relates to a transfer body, and at least a release layer, a first buffer layer, a second buffer layer, and a driving or active element layer are sequentially formed on the substrate and the substrate. And a transfer layer formed and configured.
[0025]
In the transfer body of the present invention, the transfer layer is peeled off at the interface between the substrate and the peeling layer, and is transferred and formed on the plastic film via an adhesive layer to form an element substrate for a display device. In the transfer layer of the transfer body of the present invention, as described above, when the release layer is removed after being transferred onto the plastic film, the underlying first buffer layer functions as a barrier film. For this reason, desired various element layers and the like can be formed on the plastic film with a high yield without causing any problems.
[0026]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0027]
(First embodiment)
1 to 3 are cross-sectional views sequentially showing a method for manufacturing an element substrate for a display device according to the first embodiment of the present invention. In the first embodiment, a method for manufacturing an element substrate for an organic EL display device as an element substrate for a display device will be described as an example. In the method for manufacturing an element substrate for a display device according to the first embodiment of the present invention, as shown in FIG. 1A, first, a glass substrate 20 (substrate) such as soda-lime glass having heat resistance is prepared, A release layer 22 made of a polyimide resin having a thickness of about 4 μm is formed on the glass substrate 20. As an example of a method for forming the release layer 22, a coating solution in which a polyimide precursor solution and ethylene glycol monomethyl ether are mixed at a ratio of 1: 1 is applied on the glass substrate 20 with a spinner at 1000 rpm for 12 seconds. After the application, the release layer 22 is obtained by curing by heat treatment at a temperature of 220 ° C. for 1 hour.
[0028]
Subsequently, as shown in FIG. 1B, the first buffer layer 24 is formed on the release layer 22 by sputtering, vapor deposition, ion plating, or the like. As will be described later, the first buffer layer 24 functions as a barrier film when the release layer 22 is removed after the transfer layer is transferred and formed on the plastic film.
[0029]
Therefore, the first buffer layer 24 is an O used for removing the release layer 22. ₂ / CF _Four A material that is resistant to gas plasma and an alkaline solution and that can be selectively removed with respect to a second buffer layer (inorganic insulating film) described later is used. As the first buffer layer 24, for example, a single layer film selected from the group of conductive thin films such as a copper (Cu) film, an aluminum (Al) film, an ITO film, a chromium (Cr) film, and a nickel (Ni) film A laminated film or an alloy film thereof is used.
[0030]
The film thickness of the first buffer layer 24 is not particularly limited, but it can be easily removed, has sufficient barrier properties when removing the release layer 22, and has an etching selectivity with the release layer 22. In consideration, it is preferable to set the thickness to 5 to 300 nm, desirably 50 to 150 nm.
[0031]
Next, a second buffer layer 26 having a thickness of 5 to 30 nm is formed on the first buffer layer 24. The second buffer layer 26 is preferably a film resistant to chemicals such as phosphoric acid and nitric acid that are used when the first buffer layer 24 is removed. As the second buffer layer 26, for example, a silicon oxide film (SiO _X An inorganic insulating film such as a film) or a silicon nitride film (SiNx film) is used. Further, a silicon oxide film and a silicon nitride film may be laminated. As the formation method, sputtering, vapor deposition, CVD or the like is used.
[0032]
Next, as shown in FIG. 1C, an active element (not shown) such as a TFT element or an MIM element and an anode 28 (pixel electrode) made of an ITO film connected thereto are formed on the second buffer layer 26. To do. The active element and the anode 28 (pixel electrode) connected to the active element are an example of the active element. Although not particularly shown, when a TFT element is used, an n-type polycrystalline silicon layer patterned in an island shape is first formed on the second buffer layer 26. Thereafter, a gate insulating film is formed on the polycrystalline silicon layer, and then a gate electrode made of an Al film or the like is formed on the gate insulating film. Next, using this gate electrode as a mask, a p-type conductive impurity is introduced to form a source portion and a drain portion, and a p-channel TFT element is obtained. The anode 28 is electrically connected to the source portion of the TFT element.
[0033]
In the case of manufacturing a simple matrix type display device element substrate, a transparent electrode (an example of a drive element layer) made of a striped ITO film is formed.
[0034]
In the present embodiment, an organic EL layer is finally formed on the anode 28. The organic EL layer is an ultraviolet light related to a photolithography process for forming a subsequent color filter layer, a process for removing the peeling layer, and the like. It is vulnerable to moisture, heat, organic solvents, etc., and the light emission characteristics are likely to deteriorate due to these effects. For this reason, it is important that the organic EL layer is formed after a transfer layer including a TFT element or the like is transferred to a plastic film.
[0035]
Subsequently, as shown in FIG. 1 (d), a resin coating solution such as an acrylic thermosetting resin is applied on the structure of FIG. 1 (c), and then heated and cured to have a thickness of 2 to 5 μm. A transparent protective film 30 is formed. As a result, the step between the active element and the anode 28 connected thereto is filled with the transparent protective film 30 and flattened.
[0036]
In this embodiment, a white light emitting layer is used as the organic EL layer, and an EL display device of a type that performs color display by combining the color filter layers is exemplified, so that the color filter layer 32 is formed in the following process. That is, first, the light shielding layer 32 d is patterned between the patterns of the anode 28 on the transparent protective film 30. Subsequently, the red color filter layer 32a is patterned on the portion constituting the red pixel portion. Next, the green color filter layer 32b is patterned on the portion constituting the green pixel portion. Thereafter, the blue color filter layer 32c is patterned on the portion constituting the blue pixel portion.
[0037]
In this manner, the color filter layer 32 including the red color filter layer 32a, the green color filter layer 32b, the blue color filter layer 32c, and the light shielding layer 32d is formed. The color filter layers 32a to 32d for each color are formed, for example, by patterning a pigment dispersion type photosensitive coating film by photolithography.
[0038]
Needless to say, when the light emitting layers of three colors of red, green and blue are used as the organic EL layer, it is not necessary to form the color filter layer 32.
[0039]
Next, as shown in FIG. 2A, by spraying a small amount of spacer particles having a particle size of 2 to 15 μm mixed and dispersed in an ultraviolet curable resin, the film thickness is 2 to 2 on the color filter layer 32. A 15 μm adhesive layer 34 is formed. At this time, the level difference of the color filter layer 32 is buried and flattened by the adhesive layer 34.
[0040]
Thereby, on the glass substrate 20, in order from the bottom, the peeling layer 22, the first buffer layer 24, the second buffer layer 26, the anode 28 (or striped transparent electrode) connected to the active element, and the transparent protective film 30. A transfer layer 35 composed of the color filter layer 32 and the adhesive layer 34 is formed. In this way, the transfer body 37 of the present embodiment configured by the glass substrate 20 and the transfer layer 35 formed thereon is obtained.
[0041]
When the color filter layer 32 is omitted, the active element and the anode 28 (pixel electrode) may be embedded with the adhesive layer 34 without forming the transparent protective film 30.
[0042]
Next, a method for transferring the transfer layer 35 formed on the glass substrate 20 onto the plastic film will be described. Similarly, as shown in FIG. 2A, first, a plastic film 10 corresponding to the size of the glass substrate 20 is prepared. As the plastic film 10, a polyethersulfone film or a polycarbonate film having a film thickness of 100 to 200 μm can be used.
[0043]
Thereafter, the plastic film 10 is placed on the surface of the transfer body 37 facing the adhesive layer 34 so as to face each other. Subsequently, the plastic film 10 and the transfer body 37 are bonded together by curing the adhesive layer 34 that is an ultraviolet curable resin by performing UV irradiation from the plastic film 10 side with a high-pressure mercury lamp.
[0044]
A pulse xenon light source may be used instead of the high pressure mercury lamp. Since the pulse xenon light source has high emission intensity and can cure the adhesive layer 34 in a short irradiation time, the temperature rise of the plastic film 10 due to irradiation can be suppressed.
[0045]
2A, a roll 40 having a diameter of about 200 mm is fixed to one end of the plastic film 10, and the plastic film 10 is peeled off while the roll 40 is rotated. At this time, it peels along the interface (A part of Fig.2 (a)) of the glass substrate 20 and the peeling layer 22. FIG.
[0046]
As a result, as shown in FIG. 2B, the adhesive layer 34, the color filter layer 32, the transparent protective film 30, and the anode 28 (or stripe-shaped anode connected to the active element) are sequentially formed on the plastic film 10 from the bottom. A transfer layer 35 composed of the transparent electrode), the second buffer layer 26, the first buffer layer 24, and the release layer 22 is transferred and formed.
[0047]
Next, as shown in FIG. 2 (c), the release layer 22 on the plastic film 10 is made O. ₂ / CF _Four Etching is removed by plasma using gas. At this time, under the release layer 22, O ₂ / CF _Four Since the first buffer layer 24 (conductive thin film) having a low etching rate with gas plasma is formed over the entire surface, the surface of the second buffer layer 26 is not exposed in the step of removing the release layer 22. Therefore, in the step of removing the release layer 22, the second buffer layer 26 (inorganic insulating film), the active element, and the anode 28 connected thereto are not likely to be etched and are not damaged.
[0048]
Moreover, even if the surface layer portion of the first buffer layer 24 is O ₂ / CF _Four Even if the etching is damaged by the plasma, the first buffer layer 24 is selectively removed with respect to the underlying second buffer layer 26 in the next step, so there is no problem.
[0049]
Similarly, when the peeling layer 22 is removed by wet etching using a high-temperature alkali solution or an alkali solvent mixed solution, the first buffer layer 24 becomes a barrier film, and therefore the second buffer layer 26 below the first buffer layer 26. There is no risk of etching.
[0050]
Next, as shown in FIG. 3A, the first buffer layer 24 is selectively removed with respect to the underlying second buffer layer 26. For example, when an Al film is used as the first buffer layer 24, the first buffer layer 25 is selected without damaging the underlying second buffer layer 26 (such as a silicon oxide film) by wet etching using phosphoric acid. Can be removed. When a Cu film is used as the first buffer layer 24, the first buffer layer 24 may be selectively removed by wet etching using a cupric chloride solution.
[0051]
Next, as shown in FIG. 3B, an opening 26x is formed in the portion of the second buffer layer 26 corresponding to the anode 28 connected to the active element, thereby exposing the upper surface 28a of the anode 28. At this time, the opening 26x is preferably formed with an area smaller than the area of the anode 28 (pixel electrode). Also, when a simple matrix type striped transparent electrode is used, the opening 26x is formed with a width smaller than the width of the transparent electrode.
[0052]
As described above, in the step of removing the release layer 22, the anode 28 is completely protected by the first and second buffer layers 24, 26, so that the upper surface 28a of the anode 28 is flat as in the film formation. Have Since the organic EL layer is formed on the upper surface 28a of the anode 28 in a later step, it is important to reduce the surface roughness of the upper surface 28a of the anode 28 from the viewpoint of suppressing the thickness unevenness of the organic EL layer.
[0053]
Further, the anode 28 in FIG. 3B is obtained by turning the anode 28 (ITO film) in FIG. 1C formed by sputtering or the like onto the plastic film 10 and turning upside down. Therefore, the upper surface 28a of the anode 28 in FIG. 3 (b) corresponds to the lower surface of the anode 28 in FIG. 1 (c).
[0054]
As a result of measuring the surface roughness Ra of the upper surface of the anode 28 (ITO film) of FIG. 1C formed by sputtering, the inventor of the present application showed Ra = 1.8 nm (maximum step Rmax = 19.4 nm). . Further, as a result of measuring the surface roughness Ra of the upper surface (corresponding to the lower surface of the anode 28 in FIG. 1C) of the anode 28 (ITO film) after being transferred and formed on the plastic film 10, Ra = 0. It was 7 nm (maximum step Rmax = 7.9 nm). Thus, it was found that the surface roughness Ra of the ITO film formed by sputtering is smaller on the lower surface (back surface) than on the upper surface (front surface).
[0055]
In other words, since the transfer technique is used in the present embodiment, the upper surface of the anode 28 uses the lower surface of the ITO film immediately after the film formation, and therefore the surface roughness of the upper surface of the anode 28 compared to the case where the transfer technique is not used. It is also convenient in that Ra can be reduced.
[0056]
Next, as shown in FIG. 3C, a hole transport layer, a white light emitting layer, and an electron transport layer are sequentially formed on the upper surface 28a of the anode 28 exposed at the opening 26x of the second buffer layer 26 by printing or the like. The organic EL layer 36 is used. At this time, since the organic EL layer 36 is formed on the anode 28 having a small surface roughness for the reasons described above, the organic EL layer 36 is formed in a flat state without causing unevenness in thickness.
[0057]
Next, a cathode 38 (upper electrode) that covers the organic EL layer 36 is formed on the entire surface. In the case of the simple matrix type, a striped cathode (upper electrode) orthogonal to the striped transparent electrode (anode) is formed. In this way, the organic EL element 42 having a structure in which the organic EL layer 36 is sandwiched between the anode 28 and the cathode 38 is formed.
[0058]
Thereafter, as shown in FIG. 3D, a protective film 39 covering the cathode 38 is formed. This protective film 39 is provided to prevent the deterioration of the organic EL element 42 due to an oxidizing atmosphere or moisture from the outside.
[0059]
Thus, the display device element substrate 1 (organic EL display device) manufactured by the manufacturing method of the first embodiment is completed.
[0060]
In the element substrate 1 for a display device according to the present embodiment, a positive voltage is applied to the anode 28 of the organic EL element 42 and a negative voltage is applied to the cathode 38, whereby the anode 28 is injected through the hole injection layer. White light is emitted by recombination of holes and electrons injected from the cathode 38 through the electron transport layer inside the organic EL layer 36. Then, the white light passes through the color filter layer 32 and the like and is emitted to the outside to obtain an image (in the direction of the arrow in FIG. 3D).
[0061]
Since the organic EL layer 36 according to this embodiment is formed in a flat state with no thickness unevenness as described above, it is possible to prevent the occurrence of light emission failure and improve the display characteristics of the organic EL display device.
[0062]
As described above, in the method for manufacturing an element substrate for a display device according to the present embodiment, first, the peeling layer 22, the first buffer layer 24, the second buffer layer 26, and the active element are sequentially formed on the glass substrate 20 from the bottom. A transfer layer 35 composed of the anode 28 (or stripe-shaped transparent electrode), the transparent protective film 30, the color filter layer 32, and the adhesive layer 34 connected to is formed.
[0063]
Thereafter, the transfer layer 35 is transferred and formed on the plastic film 10 via the adhesive layer 34. Next, the release layer 22 is O ₂ / CF _Four It is removed by plasma or high temperature alkaline solution. At this time, O under the release layer 22 ₂ / CF _Four Since the first buffer layer 24 having resistance to plasma or high-temperature alkaline solution is provided, there is no possibility that the second buffer layer 26 below, the active element, the anode 28 connected thereto, and the like are damaged.
[0064]
As a result, the performance of the active element and the light emission characteristics of the organic EL layer 36 can be improved. In addition, since various elements transferred and formed on the plastic film 10 are not damaged at all when the release layer 22 is removed, the manufacturing yield of the element substrate using the plastic film 10 can be improved. Furthermore, even when an element substrate is manufactured using a large substrate, it is possible to stably manufacture the device substrate without causing any problem, and thus there is an advantage that the manufacturing cost can be reduced.
[0065]
By the way, when forming active elements, such as a TFT element, on the glass substrate 20 through the peeling layer 22, processes, such as a vacuum evaporation and heat processing, are required. For this reason, impurities (such as alkali metals) contained in the release layer 22 (polyimide resin film) in these manufacturing steps diffuse into the constituent layers of the active element, thereby adversely affecting the performance of the active element. This may cause display defects in the display device.
[0066]
In the manufacturing method of the present embodiment, the active element is formed after the first buffer layer 24 and the second buffer layer 26 are stacked on the release layer 22. Since the first and second buffer layers 24 and 26 are each made of a dense conductive thin film and a dense inorganic insulating film, they also function as barrier films that prevent diffusion of impurities from the release layer 22. In addition, the function as a barrier film can be improved as compared with the case where the buffer layer is formed as a single layer. Thus, the buffer layer having a two-layer structure made of different materials as in the present embodiment is advantageous from the viewpoint of improving the performance and reliability of the active element.
[0067]
Further, when the transfer layer 35 is transferred to the plastic film 10 by peeling from the interface between the glass substrate 20 and the release layer 22, a peeling force acts in the vertical direction of the plastic film 10, so that the buffer layer has low rigidity. In some cases, the active element or the like may be peeled off from the plastic film 10. However, in the manufacturing method of the present embodiment, since the buffer layer is made of a two-layer structure made of different materials and the rigidity thereof is increased, the transfer layer 35 is stably transferred to the plastic film 10, which is used for a display device. The manufacturing yield of the element substrate can be improved.
[0068]
(Second Embodiment)
FIG. 4 is a cross-sectional view showing a method for manufacturing a display device element substrate according to the second embodiment of the present invention, and FIG. 5 is a cross-sectional view showing a liquid crystal display device using the display device element substrate according to the second embodiment of the present invention. It is. The second embodiment is different from the first embodiment in that the present invention is applied to an element substrate for a liquid crystal display device. In the second embodiment, detailed description of steps similar to those in the first embodiment is omitted.
[0069]
In the manufacturing method of the element substrate for display device of the second embodiment, as shown in FIG. 4A, first, a structure similar to that of FIG. 3A is created by the same method as that of the first embodiment. In the present embodiment, a simple matrix type liquid crystal display device will be described as an example. Therefore, the anode 28 of the organic EL element 42 in FIG. 3A of the first embodiment is striped transparent in FIG. 4A. Electrode 29 is formed. When an active matrix type liquid crystal display device is manufactured, a TFT element connected to the pixel electrode as described in the first embodiment, an MIM element connected to the pixel electrode, or the like may be formed.
[0070]
Also in the second embodiment, as in the first embodiment, since the element substrate is manufactured by providing the first and second buffer layers 24 and 26 having a two-layer structure, the transparent electrode 29 may be damaged. The production yield can be improved. In addition, the same manufacturing effects as those of the first embodiment can be obtained.
[0071]
Thereafter, as shown in FIG. 4B, an alignment film 44 for aligning a liquid crystal material with a film thickness of about 100 nm is formed on the second buffer layer 26, and the surface of the alignment film 44 is rubbed. Thereby, the scanning electrode substrate 1a (display device element substrate) for the liquid crystal display device according to the second embodiment is obtained.
[0072]
Next, a signal electrode substrate that is a counter substrate of the scan electrode substrate 1a is formed. That is, as shown in FIG. 5, the adhesive layer 34a, the transparent electrode 29a, and the second buffer layer 26a are formed on the plastic film 10b in order from the bottom using the same method as the transfer technique of the first embodiment. To do. Subsequently, an alignment film 44a is formed on the second buffer layer 26a, and a rubbing process is performed on the surface of the alignment film 40a. As a result, a signal electrode substrate 1b (a display device element substrate) serving as a counter substrate of the scanning electrode substrate 1a is obtained. Similarly, when the signal electrode substrate 1b is manufactured, there is no possibility of damaging the transparent electrode 29a.
[0073]
After that, as shown in FIG. 5 as well, the above-described scan electrode substrate 1a is prepared, and a seal material for enclosing the liquid crystal material in a predetermined region is applied by a dispenser device or a screen printing device to form the seal layer 46. Subsequently, an adhesive spacer having a particle size of about 5 μm is applied on the scan electrode substrate 1a.
[0074]
Next, the surface of the scan electrode substrate 1a on which the seal layer 46 is formed and the surface of the signal electrode substrate 1b on which the alignment film 44a is formed are connected to the transparent electrodes 29 and 29a of the two electrode substrates 1a and 1b, respectively. Align and arrange so as to be substantially orthogonal, and heat. At this time, since there is an adhesive spacer between the two electrode substrates 1a and 1b, a constant interval is maintained.
[0075]
Subsequently, individual members for a liquid crystal display device are obtained by cutting predetermined portions of the adhered scan electrode substrate 1a and signal electrode substrate 1b. Next, a liquid crystal material is injected between the scan electrode substrate 1a and the signal electrode substrate 1b from a liquid crystal injection port previously opened in the seal layer 46, and then the liquid crystal injection port is sealed with a sealant. 48 is formed.
[0076]
Thus, as shown in FIG. 5, the liquid crystal display device 2 using the display device element substrate (scanning electrode substrate 1a and signal electrode substrate 1b) of the second embodiment is completed.
[0077]
Instead of providing the color filter layer 32 on the scanning electrode substrate 1a, the color filter layer 32 may be provided, for example, between the transparent electrode 29a and the adhesive layer 34a of the signal electrode substrate 1b.
[0078]
The details of the present invention have been described above by the first and second embodiments. However, the scope of the present invention is not limited to the examples specifically shown in the above-described embodiments, and the gist of the present invention is not deviated. Variations in the above-described embodiments in scope are within the scope of the invention.
[0079]
For example, the first buffer layer 24 is a film that is resistant to plasma treatment and an alkaline solution when removing the release layer and is selectively removed with respect to the second buffer layer (inorganic insulating film) underlying the first buffer layer 24. I just need it.
[0080]
Therefore, the first buffer layer 24 is not limited to the conductive thin film described above, and various films having similar characteristics can be used. Further, since the first buffer layer 24 is finally removed, the film thickness, the material, and the like are not particularly limited, and can be formed under various conditions.
[0081]
Moreover, although the form applied to an organic EL display apparatus and a liquid crystal display device was illustrated as an element substrate for display apparatuses, it can apply to other various display apparatuses. The driving or active element layer includes a striped transparent electrode corresponding to a simple matrix type, various three-terminal elements such as a TFT element corresponding to an active matrix type, and various two-terminal elements such as an MIM element. Can be used.
[0082]
【The invention's effect】
As described above, in the present invention, the element layer, the second buffer layer (inorganic insulating film), the first buffer layer (conductive thin film), the release layer, and the like are formed on the plastic film via the adhesive layer. Like to do.
[0083]
Since the first buffer layer (conductive thin film) has resistance when the peeling layer is removed with plasma or an alkaline solution, there is no possibility that the second buffer layer and the element layer below the damage are damaged. For this reason, the manufacturing yield of the element substrate for display devices can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view (No. 1) showing a method for manufacturing an element substrate for a display device according to a first embodiment of the present invention.
FIG. 2 is a sectional view (No. 2) showing the method for manufacturing the element substrate for a display device according to the first embodiment of the present invention.
FIG. 3 is a sectional view (No. 3) showing the method for manufacturing the element substrate for a display device according to the first embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a method for manufacturing an element substrate for a display device according to a second embodiment of the present invention.
FIG. 5 is a cross-sectional view showing a liquid crystal display device using an element substrate for a display device according to a second embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Display device element substrate (organic EL display device), 1a ... Scanning electrode substrate (display device element substrate), 1b ... Signal electrode substrate (display device element substrate), 2 ... Liquid crystal display device, 10 ... Plastic film 20 ... glass substrate, 22 ... release layer, 24 ... first buffer layer, 26, 26a ... second buffer layer, 26x ... opening, 28 ... anode or stripe-like transparent electrode connected to active element (drive or Active element layer), 28a ... upper surface, 29, 29a ... transparent electrode (drive or active element layer), 30 ... transparent protective film, 32 ... color filter layer, 32a ... red color filter layer, 32b ... green color filter layer, 32c ... blue color filter layer, 32d ... light-shielding layer, 34, 34a ... adhesive layer, 35 ... transfer layer, 37 ... transfer body, 38 ... cathode, 39 ... protective film, 40 ... roll, 2 ... organic EL device, 44, 44a ... orientation film 46 ... seal layer, 48 ... liquid crystal layer.

Claims (11)

Forming a release layer made of resin on a substrate;
Forming a first buffer layer made of a conductive thin film having resistance to oxygen plasma or an alkaline aqueous solution on the entire surface of the substrate on the release layer;
Forming a second buffer layer made of an inorganic insulating film on the first buffer layer;
Forming at least a driving or active device layer on the second buffer layer;
The driving or active element layer, the second buffer layer, the first buffer layer, and the peeling layer are peeled off from the interface between the substrate and the peeling layer, and sequentially on the plastic film via an adhesive layer. A process of transferring and forming;
Removing the release layer using the first buffer layer as a barrier film;
And a step of selectively removing the entire first buffer layer with respect to the second buffer layer.   2. The method of manufacturing an element substrate for a display device according to claim 1, wherein the driving or active element layer is a striped transparent electrode, or an active element and a pixel electrode provided on the active element. After the step of removing the first buffer layer, forming an opening in a predetermined portion of the second buffer layer on the stripe-shaped transparent electrode or on the pixel electrode provided in the active element;
Forming an organic EL layer on the striped transparent electrode exposed in the opening, or on a pixel electrode provided in the active element;
Forming an upper electrode connected to the organic EL layer,
The method for manufacturing an element substrate for a display device according to claim 2, wherein the element substrate for a display device is an organic EL display device.   4. The method according to claim 3, wherein in the step of forming the opening in a predetermined portion of the second buffer layer, the opening is formed with an area smaller than an area of the transparent electrode or the pixel electrode. A method for manufacturing an element substrate for a display device.   The method for manufacturing an element substrate for a display device according to claim 1, wherein the element substrate for a display device is an element substrate for a liquid crystal display device. After the step of forming the driving or active device layer and before the step of transferring,
Forming a protective film covering the driving or active element layer;
Forming a color filter layer on the protective film,
In the transferring step, the color filter layer, the protective film, the driving or active element layer, the second buffer layer, the first buffer layer and the plastic film on the plastic film in order from the bottom. The method for manufacturing an element substrate for a display device according to claim 1, wherein the release layer is transferred. The conductive thin film is a single layer film, a laminated film or an alloy film selected from the group of a copper film, an aluminum film, a chromium film, a nickel film and an ITO film,
6. The device substrate for a display device according to claim 1, wherein the inorganic insulating film is a single layer film or a laminated film of any one of a silicon oxide film and a silicon nitride film. Method. In the step of removing the release layer, the release layer is removed by dry etching or an alkaline solution using a mixed gas of oxygen gas and a gas containing fluorine atoms, and
6. The method according to claim 1, wherein, in the step of removing the first buffer layer, the first buffer layer is selectively removed with respect to the second buffer layer by wet etching. The manufacturing method of the element substrate for display apparatuses of description. A transfer body for manufacturing an element substrate for a display device,
A substrate,
On the substrate, at least a release layer made of resin , a first buffer layer made of a conductive thin film resistant to oxygen plasma or an alkaline aqueous solution , a second buffer layer made of an inorganic insulating film, and a drive or active element layer A transfer body comprising a transfer layer formed and configured in order.   The transfer body according to claim 9, wherein the driving or active element layer is a stripe-shaped transparent electrode, or an active element and a pixel electrode provided on the active element.   The transfer body according to claim 9 or 10, wherein the transfer layer is peeled off from an interface between the substrate and the release layer, and is transferred and formed on a plastic film via an adhesive layer.

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