JP2020080322A - Flexible OLED device, manufacturing method thereof, and supporting substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an ultraviolet laser beam used in a peeling process from deteriorating a TFT element and an OLED element.
According to a method of manufacturing a flexible OLED device of the present disclosure, a base (10), a functional layer region (20) including a TFT layer and an OLED layer, and a functional layer located between the base and the functional layer region are provided. A laminated structure (100) comprising a flexible film (30) supporting a layer region and a dielectric multilayer mirror (36) located between the flexible film and the functional layer region is prepared. The flexible film is irradiated with the peeling light (216) transmitted through the base to peel the flexible film from the base.
[Selection diagram] Fig. 7D

Description

  The present disclosure relates to a flexible OLED device and a manufacturing method thereof. The invention also relates to a support substrate used in a method of manufacturing a flexible OLED device.

  A typical example of the flexible display is a film (hereinafter referred to as “resin film”) formed of a synthetic resin such as polyimide, a TFT (Thin Film Transistor) and an OLED (Organic Light Emitting Diode) supported by the resin film. It is equipped with the element. The resin film functions as a flexible substrate. Since the organic semiconductor layer forming the OLED is easily deteriorated by water vapor, the flexible display is sealed with a gas barrier film (sealing film).

  The flexible display may be manufactured using a glass base on which a resin film is formed. The glass base functions as a support (carrier) that keeps the shape of the resin film flat during the manufacturing process. By forming elements such as TFTs and OLEDs and a gas barrier film on the resin film, the structure of the flexible OLED device is realized while being supported by the glass base. The flexible OLED device is then peeled from the glass base to gain flexibility. A portion where elements such as TFTs and OLEDs are arranged can be collectively called a “functional layer region”.

  Patent Document 1 discloses a method of irradiating the interface between the flexible substrate and the glass base with ultraviolet laser light (peeling light) in order to peel the flexible substrate on which the OLED device is mounted from the glass base. In the method disclosed in Patent Document 1, an amorphous silicon layer is arranged between the flexible substrate and the glass base. Irradiation with the ultraviolet laser light generates hydrogen from the amorphous silicon layer and peels the flexible substrate from the glass base.

International Publication No. 2009/037797

  Conventionally, since the resin film used for the flexible substrate absorbs ultraviolet rays, the influence of the peeling light irradiation on the TFT element and the OLED element has not been particularly studied. According to the study by the present inventor, it was found that the ultraviolet laser light used in the peeling step may deteriorate the TFT element and the OLED element.

  The present disclosure provides a flexible OLED device, a method for manufacturing the same, and a supporting substrate that can solve the above problems.

  In an exemplary embodiment, a method of manufacturing a flexible OLED device according to the present disclosure includes a base, a functional layer region including a TFT layer and an OLED layer, and the functional layer located between the base and the functional layer region. A step of preparing a laminated structure comprising a flexible film supporting a region and a dielectric multilayer film mirror located between the flexible film and the functional layer region, and a flexible film with an ultraviolet laser beam transmitted through the base And peeling off the flexible film from the base.

  In one embodiment, the step of preparing the laminated structure includes the step of forming the dielectric multilayer film mirror on the flexible film, the step of forming a gas barrier film on the dielectric multilayer film mirror, and the gas barrier. A step of forming a semiconductor layer on the film, and a step of irradiating the semiconductor layer with laser light having a second wavelength different from the first wavelength of the ultraviolet laser light to modify the semiconductor layer. Including, the reflectance of the dielectric multilayer mirror is relatively lower at the second wavelength than at the first wavelength.

  In one embodiment, the ultraviolet laser light having the first wavelength is incident on the dielectric multilayer mirror after passing through the base and the flexible film, and the laser light having the second wavelength is After passing through the semiconductor layer, it enters the dielectric layer film mirror.

  In one embodiment, the step of preparing the laminated structure is a step of forming the dielectric multilayer mirror on the flexible film, and forming a high refractive index layer having a first refractive index, And a step of repeatedly forming a low refractive index layer having a second refractive index lower than the first refractive index.

  In one embodiment, the total thickness of the high refractive index layers included in the dielectric multilayer mirror is 100 nm or more.

  In one embodiment, the gas barrier film has a thickness of 200 nm or less.

In one embodiment, the high refractive index layer comprises Si ₃ N ₄ , SiN _x , Al ₂ O ₃ , HfO ₂ , Sc ₂ O ₃ , Y ₂ O ₃ , ZrO ₂ , Ta ₂ O ₅ , TiO ₂ , and The low refractive index layer is formed of at least one material selected from the group consisting of Nb ₂ O ₅ , and the low refractive index layer is composed of SiO ₂ , MgF ₂ , CaF ₂ , AlF ₃ , YF ₃ , LiF, and NaF. It is formed of at least one material selected from

  In one embodiment, the thickness of the flexible film is 5 μm or more and 20 μm or less.

  The flexible OLED device of the present disclosure is, in an exemplary embodiment, a functional layer region including a TFT layer and an OLED layer, a flexible film supporting the functional layer region, and between the flexible film and the functional layer region. And a dielectric multilayer mirror located therein.

  In one embodiment, the dielectric multilayer mirror has three or more high-refractive index layers each having a first refractive index, and a second refractive index lower than the first refractive index. And two or more low refractive index layers positioned between the three or more high refractive index layers.

  The support substrate of the present disclosure is, in an exemplary embodiment, a support substrate of a flexible OLED device, which includes a base formed of a material that transmits ultraviolet light, a flexible film supported by the base, and the flexible film. A supported dielectric multilayer mirror.

  In one embodiment, the dielectric multilayer mirror has three or more high-refractive index layers each having a first refractive index, and a second refractive index lower than the first refractive index. And having two or more low refractive index layers located between the three or more high refractive index layers.

  According to the embodiments of the present invention, a new method for manufacturing a flexible OLED device and a supporting substrate that solve the above problems are provided.

FIG. 6 is a plan view showing a configuration example of a laminated structure used in the method for manufacturing a flexible OLED device according to the present disclosure. FIG. 1B is a cross-sectional view taken along line BB of the laminated structure shown in FIG. 1A. FIG. 7 is a process cross-sectional view illustrating the method for manufacturing the support substrate according to the embodiment of the present disclosure. FIG. 7 is a process cross-sectional view illustrating the method for manufacturing the support substrate according to the embodiment of the present disclosure. FIG. 7 is a process cross-sectional view illustrating the method for manufacturing the support substrate according to the embodiment of the present disclosure. FIG. 6 is a process cross-sectional view illustrating a method for manufacturing a flexible OLED device according to an embodiment of the present disclosure. FIG. 6 is a process cross-sectional view showing a method for manufacturing a flexible OLED device in an embodiment of the present disclosure. FIG. 6 is a process cross-sectional view illustrating a method for manufacturing a flexible OLED device according to an embodiment of the present disclosure. FIG. 6 is a process cross-sectional view showing a method for manufacturing a flexible OLED device in an embodiment of the present disclosure. It is an equivalent circuit schematic of one sub pixel in a flexible OLED device. It is a perspective view of a laminated structure in the middle of a manufacturing process. It is sectional drawing which shows the division position of a laminated structure typically. It is a top view which shows the division position of a laminated structure typically. It is a figure which shows typically the state just before a stage supports a laminated structure. It is a figure which shows typically the state which has supported the laminated structure by the stage. It is a figure which shows typically the state which irradiates the interface of the base and resin film of a laminated structure with the laser beam (peeling light) shape|molded in the shape of a line. FIG. 5 is a cross-sectional view schematically showing reflection of peeling light by a dielectric multilayer film mirror according to an embodiment of the present disclosure. It is a perspective view which shows typically a mode that the laminated structure is irradiated with the line beam emitted from the line beam light source of the peeling apparatus. It is a figure which shows typically the position of the stage at the time of the irradiation start of peeling light. It is a figure which shows typically the position of the stage at the time of completion|finish of irradiation of peeling light. It is sectional drawing which shows typically the state before isolate|separating a laminated structure into a 1st part and a 2nd part after irradiation of peeling light. It is sectional drawing which shows typically the state which separated the laminated structure into the 1st part and the 2nd part. FIG. 3 is a cross-sectional view showing a flexible OLED device according to an embodiment of the present disclosure.

  Conventionally, the flexible substrate has been formed from a resin material typified by polyimide. Since such a resin material absorbs ultraviolet rays, it has been considered that it is not necessary to study the influence of the irradiation of peeling light on the TFT element and the OLED element. However, according to the study by the present inventor, when the thickness of the flexible substrate becomes as thin as about 5 μm to 15 μm, it may not sufficiently absorb the ultraviolet rays, and the ultraviolet laser light used in the peeling step may cause the TFT element and the OLED element to be absorbed. It has been found that there is a possibility of deteriorating. This problem occurred even when the release layer made of amorphous silicon was provided. This is because amorphous silicon can transmit ultraviolet rays. On the other hand, when the release layer is formed of a refractory metal, the refractory metal absorbs or reflects and does not transmit ultraviolet rays, so that the influence of peeling light irradiation on the TFT element and the OLED element can be prevented. However, forming a release layer using a refractory metal causes a significant increase in manufacturing cost.

  The method for manufacturing a flexible OLED device of the present disclosure enables reduction of the influence of irradiation of peeling light on a TFT element and an OLED element even when peeling light can pass through the flexible film.

  Hereinafter, embodiments of a method and an apparatus for manufacturing a flexible OLED device according to the present disclosure will be described with reference to the drawings. In the following description, more detailed description than necessary may be omitted. For example, detailed description of well-known matters or duplicate description of substantially the same configuration may be omitted. This is to prevent the following description from being unnecessarily redundant and to facilitate understanding by those skilled in the art. The present inventors provide the accompanying drawings and the following description for those skilled in the art to fully understand the present disclosure. They are not intended to limit the claimed subject matter.

<Laminate structure>
Please refer to FIG. 1A and FIG. 1B. In the method of manufacturing a flexible OLED device according to this embodiment, first, the laminated structure 100 illustrated in FIGS. 1A and 1B is prepared. 1A is a plan view of the laminated structure 100, and FIG. 1B is a sectional view taken along line BB of the laminated structure 100 shown in FIG. 1A. For reference, an XYZ coordinate system having an X axis, a Y axis, and a Z axis that are orthogonal to each other is shown in FIGS. 1A and 1B.

  The laminated structure 100 in the present embodiment includes a base (mother substrate or carrier) 10, a flexible film 30 located between the base 10 and the functional layer region 20 to support the functional layer region 20, and a flexible film 30. A dielectric multilayer film mirror (dielectric reflective film) 36 located between the functional layer region 20 and the functional layer region 20. The functional layer region 20 has a TFT layer 20A and an OLED layer 20B. The laminated structure 100 further includes a protective sheet 50 that covers the plurality of functional layer regions 20, and a gas barrier film 40 that covers the entire functional layer region 20 between the plurality of functional layer regions 20 and the protective sheet 50. I have it. The laminated structure 100 may have other layers (not shown) such as a buffer layer.

  A typical example of the base 10 is a rigid glass base. A typical example of the flexible film 30 is a flexible synthetic resin film. Hereinafter, the "flexible film" is simply referred to as "resin film". The structure including the dielectric multilayer mirror 36, the resin film 30 that supports the dielectric multilayer mirror 36, and the base 10 that supports the resin film 30 as a whole is a "support substrate" of the flexible OLED device. Called.

  The first surface 100a of the laminated structure 100 in the present embodiment is defined by the base 10, and the second surface 100b is defined by the protective sheet 50. The base 10 and the protective sheet 50 are members that are temporarily used during the manufacturing process and are not elements that make up the final flexible OLED device.

  The illustrated resin film 30 includes a plurality of flexible substrate regions 30d respectively supporting the plurality of functional layer regions 20, and an intermediate region 30i surrounding each flexible substrate region 30d. The flexible substrate region 30d and the intermediate region 30i are merely different portions of one continuous resin film 30 and do not need to be physically distinguished. In other words, the portion of the resin film 30 located directly below each functional layer region 20 is the flexible substrate region 30d, and the other portion is the intermediate region 30i.

  Each of the functional layer regions 20 finally constitutes a panel of the flexible OLED device. In other words, the laminated structure 100 has a structure in which one base 10 supports a plurality of flexible OLED devices before division. Each functional layer region 20 has, for example, a shape having a thickness (Z-axis direction size) of several tens of μm, a length (X-axis direction size) of about 12 cm, and a width (Y-axis direction size) of about 7 cm. is doing. These sizes can be set to any size according to the size of the required display screen. The shape of each functional layer region 20 in the XY plane is a rectangle in the illustrated example, but is not limited to this. The shape of each functional layer region 20 in the XY plane may be a square, a polygon, or a shape including a curved line in its contour.

  As shown in FIG. 1A, the flexible substrate regions 30d are two-dimensionally arranged in rows and columns corresponding to the arrangement of the flexible OLED devices. The intermediate region 30i is composed of a plurality of orthogonal stripes and forms a lattice pattern. The width of the stripe is, for example, about 1 to 4 mm. The flexible substrate region 30d of the resin film 30 functions as a "flexible substrate" of each flexible OLED device in the form of the final product. On the other hand, the intermediate region 30i of the resin film 30 is not an element that constitutes the final product.

  In the embodiment of the present disclosure, the configuration of the laminated structure 100 is not limited to the illustrated example. The number of functional layer regions 20 (the number of OLED devices) supported by one base 10 does not have to be plural, and may be singular. When the functional layer region 20 is singular, the intermediate region 30i of the resin film 30 forms a simple frame pattern surrounding one functional layer region 20.

  It should be noted that the size or ratio of each element described in each drawing is determined from the viewpoint of intelligibility, and does not necessarily reflect the actual size or ratio.

Support Substrate With reference to FIG. 2A and FIG. 2B, the support substrate and the manufacturing method thereof according to the embodiment of the present disclosure will be described. 2A and 2B are process cross-sectional views showing the method of manufacturing the support substrate 200 according to the embodiment of the present disclosure.

<Base>
First, as shown in FIG. 2A, the base 10 is prepared. The base 10 is a carrier substrate for the process, and the thickness thereof can be, for example, about 0.3 to 0.7 mm. The base 10 is typically made of glass. The base 10 is required to transmit the peeling light that is applied in a later step.

<Resin film>
Next, as shown in FIG. 2B, a resin film 30 is formed on the base 10. The resin film 30 in the present embodiment is, for example, a polyimide film having a thickness of 5 μm or more and 20 μm or less, for example, about 10 μm. The polyimide film can be formed from a precursor polyamic acid or a polyimide solution. Thermal imidization may be performed after forming the polyamic acid film on the surface of the supporting substrate 200, or the film may be formed on the surface of the base 10 from a polyimide solution obtained by melting polyimide or dissolving it in an organic solvent. The polyimide solution can be obtained by dissolving a known polyimide in any organic solvent. A polyimide film may be formed by applying a polyimide solution to the surface of the base 10 and then drying.

  In the case of a bottom emission type flexible display, it is preferable that the polyimide film realizes a high transmittance in the entire visible light region. The transparency of the polyimide film can be expressed by the total light transmittance according to JIS K7105-1981, for example. The total light transmittance can be set to 80% or higher, or 85% or higher. On the other hand, in the case of a top emission type flexible display, the transmittance is not affected. The refractive index of the polyimide film is, for example, about 1.7.

  The resin film 30 may be a film formed of a synthetic resin other than polyimide. However, in the embodiment of the present disclosure, the heat treatment at 350° C. or higher is performed in the step of forming the thin film transistor, so that the resin film 30 is formed from a material that is not deteriorated by the heat treatment.

  The resin film 30 may be a laminated body of a plurality of synthetic resin films. In an aspect of this embodiment, when peeling the structure of the flexible display from the base 10, a peeling light irradiation step of irradiating the resin film 30 with the ultraviolet laser light (wavelength: 300 to 360 nm) that passes through the base 10 is performed. .. A release layer such as an amorphous silicon layer that absorbs ultraviolet laser light and emits hydrogen gas may be disposed between the base 10 and the resin film 30. In the peeling step described below, part of the resin film 30 (layered portion) is vaporized at the interface between the base 10 and the resin film 30 by irradiation with ultraviolet laser light, and the resin film 30 can be peeled from the base 10. The release layer has the effect of suppressing the generation of ash.

  In the embodiment of the present disclosure, the dielectric multilayer mirror 36 described below functions as an ultraviolet ray transmission suppressing layer in the peeling light irradiation step. As a result, it is avoided or suppressed that the ultraviolet laser light enters the functional layer region 20 from the base 10 and deteriorates the characteristics of the TFT layer 20A and the OLED layer 20B.

  It has been generally considered that even the highly transparent resin film 30 absorbs almost all ultraviolet rays. However, since the resin film 30 used in the flexible OLED device is an extremely thin layer, the ultraviolet laser light can enter the functional layer region 20 in the peeling light irradiation step. The ultraviolet laser light may deteriorate not only the characteristics of the TFT layer 20A and the OLED layer 20B but also the sealing performance of the organic film and the inorganic film forming the sealing structure. Further, since the resin film 30 which is widely used at present is formed of a yellowish brown or brownish brown polyimide material, it is not recognized that the transmission of the ultraviolet laser light may cause the characteristic deterioration of the functional layer region. This is because such a polyimide material having low transparency strongly absorbs the ultraviolet laser light. However, according to the study by the present inventor, it has been found that even if the resin film 30 has low transparency, the ultraviolet laser light can reach the functional layer region 20 as long as the thickness is only about 5 to 20 μm. . Therefore, the method according to the embodiment of the present disclosure is not limited to an OLED device including a resin film (flexible substrate) formed of a material having high transparency and easily transmitting ultraviolet rays, but also a thin resin film 30 having low transparency (thickness: The thickness is about 5 to 20 μm).

  When a polishing target (target) such as particles or convex portions is present on the surface of the resin film 30, the target may be polished by a polishing device to be flattened. The foreign matter such as particles can be detected by processing an image acquired by an image sensor, for example. After the polishing process, the surface of the resin film 30 may be flattened. The flattening process includes a step of forming a film (flattening film) for improving flatness on the surface of the resin film 30. The flattening film does not have to be formed of resin.

<Dielectric multilayer mirror>
Next, as shown in FIG. 2C, a dielectric multilayer film mirror 36 is formed on the resin film 30.

  In the present disclosure, a “dielectric multilayer mirror” is a stack of multi-layers composed of k dielectric layers, where k is an integer of 5 or more, It means a laminated body in which the optical thickness of each dielectric layer is adjusted so that the light reflected by the interface of the dielectric layers having different refractive indexes causes constructive interference.

  The dielectric layer constituting the dielectric multilayer film mirror is counted from the side on which the separation light is incident, and the i-th layer is referred to as a dielectric layer (i). i is an integer of 1 or more and k or less. The refractive index of the dielectric layer (i) is n(i), and the thickness is d(i). In an embodiment of the present disclosure, n(i+1) is lower than n(i) and n(i+2) when i is an odd number. Therefore, the odd-numbered dielectric layers (odd numbers) are referred to as “high refractive index layers”, and the even-numbered dielectric layers (even numbers) are referred to as “low refractive index layers”.

  The optical thickness of the dielectric layer (i) is defined by n(i)×d(i). When the wavelength of the peeling light in vacuum is λ, the optical thickness in this embodiment, that is, n(i)×d(i), is equal to λ/4. If n(i)×d(i)=λ/4 holds, the respective refractive indexes and thicknesses of all “high refractive index layers” do not need to match each other. Similarly, the respective refractive indices and thicknesses of all "low refractive index layers" need not match each other. However, since the “high refractive index layer” is typically formed from the same material having the same refractive index, the thickness of each “high refractive index layer” is the same. In addition, typically, the “low refractive index layer” is also formed of the same material having the same refractive index, so that the thickness of each “low refractive index layer” is the same. However, the embodiment of the present disclosure is not limited to such an example.

  In the example shown in FIG. 2C, the dielectric multilayer mirror 36 has five dielectric layers (1), a dielectric layer (2), a dielectric layer (3), a dielectric layer (4), and a dielectric layer. It is composed of (5). The dielectric layer (1), the dielectric layer (3) and the dielectric layer (5) are the high refractive index layer 36A. The dielectric layer (2) and the dielectric layer (4) are the low refractive index layer 36B. In other words, the dielectric multilayer mirror 36 in the illustrated example has three or more high refractive index layers 36A each having a first refractive index, and a second refractive index lower than the first refractive index. And two or more low refractive index layers 36B located between the three or more high refractive index layers 36A. It should be noted that "high" and "low" in the terms "high refractive index layer" and "low refractive index layer" are not absolute sizes but exist between adjacent dielectric layers so as to form an interface. It only means the relative relationship of the refractive indices.

High refractive index layer is, for _{example, Si 3 N 4, SiN x} , Al 2 O 3, HfO 2, Sc 2 O 3, Y 2 O 3, ZrO 2, Ta 2 O 5, TiO 2, and Nb ₂ O ₅ It may be formed of at least one material selected from the group consisting of: The low refractive index layer can be formed of at least one material selected from the group consisting of SiO ₂ , MgF ₂ , CaF ₂ , AlF ₃ , YF ₃ , LiF, and NaF, for example. The “high refractive index layer” included in one dielectric multilayer film mirror 36 may be formed of a plurality of types of materials having different refractive indexes. In that sense, the "first refractive index" is not limited to the singular. The terms "low refractive index layer" and "second refractive index" can be similarly interpreted.

  The reflectance at the interface between the high refractive index layer and the low refractive index layer increases as the difference in the refractive index between the high refractive index layer and the low refractive index layer increases. For this reason, it is preferable to select the material so that the difference in refractive index becomes large. The low refractive index layer is preferably formed of, for example, a fluorine-based material, and its refractive index is preferably less than 1.5. The high refractive index layer is preferably formed of, for example, silicon nitride, tantalum (Ta), hafnium (Hf), yttrium (Y), or a metal oxide such as niobium (Nb), and has a refractive index of 1. It is desirable that it is 7 or more.

  The refractive index of the resin film 30 differs depending on the synthetic resin material. The refractive index of the synthetic resin is typically in the range of about 1.5 to 1.7. Therefore, when the dielectric multilayer mirror 36 directly contacts the resin material of the resin film 30, the high refractive index layer 36A included in the dielectric multilayer mirror 36 is arranged so as to contact the resin material. With such an arrangement, the reflectance at the interface between the resin film 30 and the high refractive index layer 36A can be increased.

  In the illustrated example, when peeling light passes through the base 10 and the resin film 30 and enters the dielectric multilayer mirror 36, a part of the peeling light is first a high refractive index layer which is the dielectric layer (1). It is reflected by the interface between 36A and the resin film 30. The light transmitted through this interface is then coupled to the dielectric layer (1) and the dielectric layer (2), the dielectric layer (2) and the dielectric layer (3), and the dielectric layer (3) and the dielectric layer (3). Reflection and transmission are repeated at the interface of the body layer (4) and the interface of the dielectric layer (4) and the dielectric layer (5), respectively. When the peeling light enters the low refractive index layer 36B from the high refractive index layer 36A, so-called fixed-end reflection occurs at the interface and the phase shifts by π, that is, a half wavelength. On the other hand, when the peeling light enters the high refractive index layer 36A from the low refractive index layer 36B, so-called free end reflection occurs at the interface, and the phase does not shift. Therefore, if the optical thicknesses of the high-refractive index layer 36A and the low-refractive index layer 36B are adjusted to λ/4, the phases of the reflections at the interfaces are aligned, and constructive interference of the reflected light is realized. In order to obtain the effect of the present invention, the optical thickness does not need to be exactly equal to the value of λ/4, and a shift of ±20% or less can be allowed. Further, the optical thickness when the reflected light from each interface realizes constructive interference is more generally λ/4+(L×λ/2). Here, L is an integer of 0 or more.

  In the example of the figure, the repetition of the high refractive index layer 36A and the low refractive index layer 36B is 2.5 cycles. Embodiments of the present disclosure are not limited to this example. The high-refractive index layer 36A and the low-refractive index layer 36B may have a repeating cycle of two cycles or three or more cycles.

  With respect to the configuration example of the dielectric multilayer film mirror 36 that can be adopted in the embodiment of the present disclosure, the reflectance was obtained by simulation. The result of this simulation will be described later.

  The dielectric multilayer mirror 36 is manufactured by alternately forming the high refractive index layers 36A and the low refractive index layers 36B by a thin film deposition technique such as vapor deposition. The high refractive index layer 36A and the low refractive index layer 36B are typically continuous films, but may be patterned. It suffices that the dielectric multilayer mirror 36 exists in a region that suppresses the peeling light from entering the TFT layer 20A and the OLED layer 20B.

  When the sheet-shaped resin film 30 is attached to the base 10, the dielectric multilayer film mirror 36 may be formed on the resin film 30 before attachment.

  The dielectric multilayer mirror 36 is a member that exerts an optical function when irradiated with peeling light in the lift-off process. However, when it is used as a flexible OLED device, ultraviolet rays included in ambient light cause the TFT layer 20A and the OLED layer to be exposed. A function of suppressing the incident on 20B and deterioration over time can also be exhibited. Further, the dielectric multilayer film mirror 36 can not only exhibit an optical function, but also a gas barrier film function described below.

<Lower layer gas barrier film>
Next, as shown in FIG. 3A, a gas barrier film 38 is formed on the dielectric multilayer film mirror 36. The gas barrier film 38 can have various structures. An example of the gas barrier film is a film such as a silicon oxide film or a silicon nitride film. Another example of the gas barrier film may be a multilayer film in which an organic material layer and an inorganic material layer are laminated. This gas barrier film may be referred to as a “lower layer gas barrier film” in order to distinguish it from a later-described gas barrier film covering the functional layer region 20. Further, the gas barrier film that covers the functional layer region 20 can be called an “upper gas barrier film”.

  The gas barrier film 38 may be in contact with the high-refractive index layer 36A or the low-refractive index layer 36B forming the dielectric multilayer film mirror 36, or between the gas barrier film 38 and the dielectric multilayer film mirror 36. Other layers may intervene. When the gas barrier film 38 and the dielectric multilayer film mirror 36 are in direct contact with each other, it is preferable that the separation light is strongly reflected also by the interface between the gas barrier film 38 and the dielectric multilayer film mirror 36. Therefore, the dielectric layer in contact with the gas barrier film 38 is preferably formed of a material having a refractive index that is substantially different from the refractive index of the gas barrier film 38.

Functional Layer Region Next, a process of forming the functional layer region 20 including the TFT layer 20A and the OLED layer 20B, and the upper gas barrier film 40 will be described. More specifically, the functional layer region 20 includes the TFT layer 20A located in the lower layer and the OLED layer 20B located in the upper layer. The TFT layer 20A and the OLED layer 20B are sequentially formed by a known method. The TFT layer 20A includes a TFT array circuit that realizes an active matrix. OLED layer 20B includes an array of OLED elements, each of which may be independently driven. The TFT layer 20A has a thickness of, for example, 4 μm, and the OLED layer 20B has a thickness of, for example, 1 μm.

<TFT layer>
First, as shown in FIG. 3B, the semiconductor layer 21 is formed on the lower gas barrier film 38. The semiconductor layer is amorphous at this stage. The semiconductor layer 21 is irradiated with laser light in order to polycrystallize (modify) at least a part of the semiconductor layer 21. At this time, a part of the laser light may pass through the semiconductor layer 21 and enter the dielectric multilayer mirror 36. When the laser beam is reflected by the dielectric multilayer film mirror 36 and enters the semiconductor layer 21, the heat treatment conditions such as the temperature rising rate of the semiconductor layer 21 may change as compared with the case where the dielectric multilayer film mirror 36 is not provided. .

However, when the semiconductor layer 21 is made of silicon, a large difference in refractive index occurs between the lower gas barrier film 38 and the semiconductor layer 21. Specifically, when the lower gas barrier film 38 is made of, for example, SiN _x (refractive index: about 1.9), since the refractive index of silicon is 4 or more, a large refractive index difference occurs at the interface, The laser light is strongly reflected at this interface. Therefore, the influence of the laser light transmitted through this interface and reflected by the dielectric multilayer film mirror 36 is reduced. This means that it is not necessary to change the laser light irradiation conditions for polycrystallizing the semiconductor layer 21 depending on the presence or absence of the dielectric reflection mirror.

  When the wavelength of the laser light for polycrystallizing the semiconductor layer is different from the wavelength of the peeling light, the reflectance of the dielectric multilayer film mirror 36 is optimized according to the wavelength of the peeling light. Therefore, such a dielectric multi-layer film mirror 36 does not strongly reflect light of other wavelengths, and thus variations in semiconductor polycrystallization conditions are unlikely to occur in the first place.

  Next, as shown in FIG. 3C, a TFT layer 20A is formed by a known TFT manufacturing process. Specifically, after patterning the semiconductor layer 21, the ground line GL is formed. After forming the gate insulating film 22, the gate electrode G is formed so as to cover the channel region of the semiconductor layer 21. Source/drain regions self-aligned with the gate electrode G are formed in the semiconductor layer 21 by ion implantation. After depositing the interlayer insulating film 23, contact holes are formed, and the source electrode S and the drain electrode D of the transistor Tr and the electrode E1 on the ground line GL are formed. After depositing the first inorganic barrier layer 24 covering these, the organic planarizing film 25 and the second inorganic barrier layer 26 are formed. In this way, the TFT layer 20A is formed. The structure and manufacturing method of the TFT layer 20A are not limited to this example, and may be various.

<OLED layer>
Next, as shown in FIG. 3D, after forming contact holes in the organic planarizing film 25 and the second inorganic barrier layer 26, the anode electrode E2 and the cathode electrode E3 of the OLED light emitting element 28 are formed. After forming the bank 27, the OLED light emitting element 28 is formed on the anode electrode E2. The OLED light emitting device 28 includes organic semiconductor layers such as a hole transport layer, a light emitting layer, and an electron transport layer. The OLED layer 20B is formed by forming the transparent electrode 29 that electrically connects the electron transport layer of the OLED light emitting element 28 and the cathode electrode E3. The configuration and manufacturing method of the OLED layer 20B are not limited to this example, and may be various. In this way, the functional layer region 20 is completed.

<Upper gas barrier film>
After forming the functional layer region 20, as shown in FIG. 3D, the entire functional layer region 20 is covered with the thin film sealing layer (upper gas barrier film) 40. A typical example of the upper gas barrier film 40 is a multilayer film in which an inorganic material layer and an organic material layer are laminated. Elements such as an adhesive film, other functional layers constituting a touch screen, and a polarizing film may be arranged between the upper gas barrier film 40 and the functional layer region 20, or further on the upper gas barrier film 40. .. The upper gas barrier film 40 can be formed by a thin film encapsulation (TFE) technique. From the viewpoint of sealing reliability, the WVTR (Water Vapor Transmission Rate) of the thin film sealing structure is typically required to be 1×10 ⁻⁴ g/m ² /day or less. According to the embodiments of the present disclosure, this criterion is achieved. The thickness of the upper gas barrier film 40 is, for example, 1.5 μm or less.

<Protection sheet>
Next, the protective sheet 50 (FIG. 1B) is attached to the upper surface of the laminated structure 100. The protective sheet 50 may be formed of a material such as polyethylene terephthalate (PET) or polyvinyl chloride (PVC). As described above, the typical example of the protective sheet 50 has a laminate structure having a release agent coating layer on its surface. The thickness of the protective sheet 50 may be, for example, 50 μm or more and 150 μm or less.

  After the laminated structure 100 manufactured in this manner is prepared, the manufacturing method according to the present disclosure can be performed using the manufacturing apparatus (peeling apparatus 220) described below.

  The laminated structure 100 that can be used in the manufacturing method of the present disclosure is not limited to the example illustrated in FIGS. 1A and 1B. The protective sheet 50 may cover the entire resin film 30 and may extend outside the resin film 30. Alternatively, the protective sheet 50 may cover the entire resin film 30 and may extend outside the base 10. As will be described later, after the base 10 is separated from the laminated structure 100, the laminated structure 100 becomes a flexible thin sheet-like structure having no rigidity. The protective sheet 50 impacts the functional layer region 20 when the functional layer region 20 collides with or contacts an external device or instrument in the process of peeling the base 10 and the process after the peeling. It plays a role of protecting from friction. Since the protective sheet 50 is finally peeled off from the laminated structure 100, a typical example of the protective sheet 50 has a laminated structure having an adhesive layer (releasing agent coating layer) having a relatively small adhesive force on the surface. is doing. A more detailed description of the laminated structure 100 will be given later.

<Equivalent circuit>
FIG. 4 is a basic equivalent circuit diagram of sub-pixels in an organic EL (Electro Luminescence) display. One pixel of the display may be composed of sub-pixels of different colors such as R (red), G (green), and B (blue). The example shown in FIG. 4 has a selection TFT element Tr1, a driving TFT element Tr2, a storage capacitor CH, and an OLED element EL. The selection TFT element Tr1 is connected to the data line DL and the selection line SL. The data line DL is a wiring that carries a data signal that defines an image to be displayed. The data line DL is electrically connected to the gate of the driving TFT element Tr2 via the selecting TFT element Tr1. The selection line SL is a wiring that carries a signal for controlling ON/OFF of the selection TFT element Tr1. The driving TFT element Tr2 controls the conduction state between the power line PL and the OLED element EL. When the driving TFT element Tr2 is turned on, a current flows from the power line PL to the ground line GL via the OLED element EL. This current causes the OLED element EL to emit light. Even if the selecting TFT element Tr1 is turned off, the holding capacitor CH keeps the driving TFT element Tr2 in the on state. The driving TFT element Tr2 corresponds to the transistor Tr in FIG. 3D.

  The TFT layer 20A includes a selection TFT element Tr1, a driving TFT element Tr2, a data line DL, a selection line SL, and the like. The OLED layer 20B includes the OLED element EL. Before the OLED layer 20B is formed, the upper surface of the TFT layer 20A is flattened by an interlayer insulating film that covers the TFT array and various wirings. The structure that supports the OLED layer 20B and realizes active matrix driving of the OLED layer 20B is referred to as a "backplane".

  Some of the circuit elements and wirings shown in FIG. 4 may be included in either the TFT layer 20A or the OLED layer 20B. Further, the wiring shown in FIG. 4 is connected to a driver circuit (not shown).

  In the embodiments of the present disclosure, the specific configurations of the TFT layer 20A and the OLED layer 20B may vary. These configurations do not limit the content of this disclosure. The structure of the TFT element included in the TFT layer 20A may be a bottom gate type or a top gate type. The light emission of the OLED element included in the OLED layer 20B may be of the bottom emission type or the top emission type. The specific configuration of the OLED element is also arbitrary.

  The material of the semiconductor layer forming the TFT element includes, for example, crystalline silicon, amorphous silicon, and an oxide semiconductor. In the embodiment of the present disclosure, in order to improve the performance of the TFT element, a part of the step of forming the TFT layer 20A includes a heat treatment step at 350° C. or higher.

  FIG. 5 is a perspective view schematically showing the upper surface side of the laminated structure 100 at the stage when the upper gas barrier film 40 is formed. One laminated structure 100 includes a plurality of OLED devices 1000 supported by the base 10. In the example shown in FIG. 5, one laminated structure 100 includes more functional layer regions 20 than the example shown in FIG. 1A. As described above, the number of the functional layer regions 20 supported by one base 10 is arbitrary.

<Division of OLED device>
In the method of manufacturing the flexible OLED device of the present embodiment, after the step of preparing the laminated structure 100 is performed, the step of dividing the intermediate region 30i of the resin film 30 and each of the plurality of flexible substrate regions 30d is performed. The step of dividing does not have to be performed before the LLO step, and may be performed after the LLO step.

  The division can be performed by cutting the central part of the adjacent OLED device with a laser beam or a dicing saw. In the present embodiment, the portion of the laminated structure other than the base 10 is cut, and the base 10 is not cut. However, the base 10 may be cut and divided into a partial laminated structure including individual OLED devices and a base portion supporting each OLED device.

  Hereinafter, a process of cutting the laminated structure other than the base 10 by irradiating the laser beam will be described. The irradiation position of the laser beam for cutting is along the outer periphery of each flexible substrate region 30d.

  FIGS. 6A and 6B are a cross-sectional view and a plan view schematically showing the position where the intermediate region 30i of the resin film 30 and each of the plurality of flexible substrate regions 30d are divided. The irradiation position of the laser beam for cutting is along the outer periphery of each flexible substrate region 30d. In FIG. 6A and FIG. 6B, the irradiation position (cutting position) CT indicated by an arrow or a broken line is irradiated with a laser beam for cutting, and the portion of the laminated structure 100 other than the base 10 is provided with a plurality of OLED devices 1000 and others. Cut into unnecessary parts. Due to the cutting, a gap of several tens μm to several hundreds μm is formed between each OLED device 1000 and its periphery. As described above, such cutting can be performed by a dicing saw instead of the laser beam irradiation. Even after cutting, the OLED device 1000 and other unnecessary parts are fixed to the base 10.

  As shown in FIG. 6B, the planar layout of the “unnecessary portion” in the laminated structure 100 matches the planar layout of the intermediate region 30i of the resin film 30. In the illustrated example, this "waste" is a continuous sheet-like structure having an opening. However, the embodiments of the present disclosure are not limited to this example. The irradiation position CT of the cutting laser beam may be set so as to divide the “unnecessary part” into a plurality of parts. The sheet-like structure that is the “unnecessary part” includes not only the intermediate region 30i of the resin film 30 but also the cut part of the laminate (for example, the gas barrier film 40 and the protective sheet 50) existing on the intermediate region 30i. Contains.

  In the case of cutting with a laser beam, the wavelength of the laser beam may be in the infrared, visible light, or ultraviolet region. From the viewpoint of reducing the influence of cutting on the base 10, a laser beam having a wavelength in the green to ultraviolet range is desirable. For example, according to the Nd:YAG laser device, the cutting can be performed using the second harmonic (wavelength 532 nm) or the third harmonic (wavelength 343 nm or 355 nm). In that case, if the laser output is adjusted to 1 to 3 watts and scanning is performed at a speed of about 500 mm per second, the laminate supported by the base 10 can be made into an OLED device and unnecessary portions without damaging the base 10. It can be cut (divided).

  According to the embodiment of the present disclosure, the timing of performing the above cutting is earlier than in the related art. Since the cutting is performed with the resin film 30 fixed to the base 10, even if the interval between the adjacent OLED devices 1000 is narrow, the positioning of the cutting can be performed with high accuracy and precision. Therefore, the interval between the adjacent OLED devices 1000 can be shortened to reduce the useless portion that is finally unnecessary.

<Irradiation of peeling light>
FIG. 7A is a diagram schematically showing a state immediately before the stage 212 in the manufacturing apparatus (separation apparatus) (not shown) supports the laminated structure 100. The stage 212 in this embodiment is a suction stage having a large number of holes for suction on its surface. The structure of the suction stage is not limited to this example, and may include an electrostatic chuck or another fixing device that supports the laminated structure. The laminated structure 100 is arranged such that the second surface 100b of the laminated structure 100 faces the surface 212S of the stage 212 and is in close contact with the stage 212.

  FIG. 7B is a diagram schematically showing a state in which the stage 212 supports the laminated structure 100. The positional relationship between the stage 212 and the laminated structure 100 is not limited to the illustrated example. For example, the stacked structure 100 may be turned upside down, and the stage 212 may be located below the stacked structure 100.

  In the example shown in FIG. 7B, the laminated structure 100 is in contact with the surface 212S of the stage 212, and the stage 212 adsorbs the laminated structure 100.

  Next, as shown in FIG. 7C, the interface between the resin film 30 and the base 10 is irradiated with ultraviolet laser light (peeling light) 216. FIG. 7C is a diagram schematically showing a state in which the resin film 30 is irradiated from the side of the base 10 by the peeling light 216 formed in a line shape extending in the direction perpendicular to the paper surface of the drawing. The resin film 30 absorbs the ultraviolet laser light and is heated in a short time. Part of the resin film 30 vaporizes or decomposes (disappears) at the interface between the base 10 and the resin film 30. By scanning the resin film 30 with the peeling light 216, the degree of fixation of the resin film 30 to the base 10 is reduced. The wavelength of the peeling light 216 is in the ultraviolet range. The light absorptance of the base 10 is, for example, about 10% in the wavelength region of 343 to 355 nm, but can increase to 30 to 60% at 308 nm.

  FIG. 7D schematically shows how the peeling light 216 enters the resin film 30. In this figure, the peeling light 216 is obliquely incident on the resin film 30 for easy understanding. The peeling light 216 typically enters the resin film 30 perpendicularly.

  FIG. 7D schematically illustrates a state in which a part of the separation light 216 that has passed through the resin film 30 is reflected from the dielectric multilayer film mirror 36.

<Simulation of peeling light reflection>
The reflectance of peeling light at a wavelength of 308 nm was calculated for the layer configurations having the materials, refractive indexes, and thicknesses shown in Table 1, Table 2, Table 3, and Table 4 below. The reflectances of 79%, 56%, 60%, and 60% were obtained for the configurations of Table 1, Table 2, Table 3, and Table 4, respectively.

  In the above example, the repetition of the high refractive index layer and the low refractive index layer is 2.5 cycles, but the reflectance increases as the number of cycles is increased. For example, in the layer structure shown in Table 2, a reflectance of 82% was realized when the number of repeating cycles was 4.5, and a reflectance of 90% was realized when the number of repeating cycles was 5.5. .. However, it is not necessary to achieve such a high reflectance, and the reflectance may be 30% or more, and the effect is sufficiently obtained if the reflectance is 50% or more.

  As described above, after depositing the semiconductor layer 21 for the TFT layer 20A, in the embodiment of the present disclosure, the semiconductor layer 21 is irradiated with laser light to perform modification for increasing the crystallinity of the semiconductor layer 21. This laser light enters the semiconductor layer 21 from the direction shown in FIG. 3B. As shown in FIGS. 7C and 7D, the peeling light 216 is incident on the dielectric multilayer mirror 36 after passing through the base 10 and the resin film 30, but the laser light that polycrystallizes the semiconductor layer 21 is a semiconductor. After passing through the layer 21, it is incident on the dielectric multilayer mirror 36. The wavelength of the laser light for modifying the semiconductor does not need to match the wavelength of the peeling light, and can be selected from a band suitable for polycrystallization of the semiconductor layer 21. As a laser irradiation device for polycrystallizing a semiconductor layer such as silicon, an excimer laser device which emits a laser beam having a wavelength of 308 nm is widely used.

  In the embodiment of the present disclosure, focusing on the fact that the wavelength of the peeling light and the wavelength of the laser light used for modifying the semiconductor layer may be different, the presence of the dielectric multilayer film mirror 36 effectively realizes the reflection of the peeling light. On the other hand, it was considered to reduce the influence on the modification of the semiconductor layer. This is because if there is unevenness in the degree of modification of the semiconductor layer 21, the characteristics of the TFTs that drive the sub-pixels of the organic EL display will differ from TFT to TFT. In the organic EL display that operates by current drive, the characteristic variation of the TFT causes unevenness in the brightness of each pixel and deteriorates the display quality. Therefore, it is desirable to reduce the reflection by the dielectric multilayer film mirror 36 with respect to the laser light (for polycrystallization annealing) that enters from the direction of the arrow in FIG. 3B. As a result of the study by the present inventors, a gas barrier film 38 made of an inorganic material is disposed between the semiconductor layer 21 and the dielectric multilayer mirror 36, and the thickness of the gas barrier film 38 is adjusted to an appropriate size. It was found that the desired function can be realized by.

  Hereinafter, Table 5, Table 6, Table 7, and Table 8 show that the reflectance is relatively high at the wavelength of laser light used for peeling (346 nm or 355 nm), and the wavelength of laser light used for polycrystallization of a semiconductor layer. At (308 nm), an example of a structure in which the reflectance is relatively reduced is shown.

According to the configuration example of Table 5 below, the reflectance at the wavelength of 308 nm is set to 45.2% by setting the thickness of the gas barrier film 38 formed of SiN _x (refractive index n=1.94) to 190 nm. At the same time, the reflectance at wavelengths of 343 nm and 355 nm is set to 76.4% and 85.7%, respectively.

In the configuration example shown in Table 6 below, the reflectance at the wavelength of 308 nm is 12.4% by setting the thickness of the gas barrier film 38 formed of SiN _x (refractive index n=1.94) to 181.8 nm. In addition, the reflectance at wavelengths of 343 nm and 355 nm is set to 60.9% and 63.6%, respectively.

In the configuration example shown in Table 7 below, the reflectance at the wavelength of 308 nm is set to 17.1% by setting the thickness of the gas barrier film 38 formed of SiN _x (refractive index n=1.94) to 24 nm. At the same time, the reflectance at wavelengths of 343 nm and 355 nm is set to 60.8% and 78.0%, respectively.

In the configuration example shown in Table 8 below, by setting the thickness of the gas barrier film 38 formed of SiN _x (refractive index n=1.94) to 190 nm, the reflectance at the wavelength of 308 nm is set to 20.4%. At the same time, the reflectances at wavelengths of 343 nm and 355 nm are set to 53.8% and 71.5%, respectively.

  As described above, by adjusting the configuration of the dielectric multilayer mirror 36 and the optical thickness of the gas barrier film 38, the reflectance of the dielectric multilayer mirror 36 is set to be higher than that of the wavelength of peeling light (first wavelength) in the semiconductor. The wavelength of the laser light for layer modification (second wavelength) can be relatively low.

  The high refractive index layer included in the dielectric multilayer mirror 36 is generally made of a dense material and exhibits a barrier effect against gases such as water vapor. Therefore, if the total thickness of the high refractive index layers included in the dielectric multilayer mirror 36 is 100 nm or more, it can be expected that the moisture resistance of the flexible OLED device is improved. When the gas barrier film 38 is arranged between the dielectric multilayer film mirror 36 and the functional layer region 20, the dielectric multilayer film mirror 36 can exhibit a function of improving the moisture resistance in addition to the optical function. It is also possible for the thickness of 38 to be 200 nm or less.

<Details of peeling light irradiation>
Hereinafter, the irradiation of peeling light in this embodiment will be described in detail.

  The peeling device according to the present embodiment includes a line beam light source that emits peeling light 216. The line beam light source includes a laser device and an optical system that shapes the laser light emitted from the laser device into a line beam.

  FIG. 8A is a perspective view schematically showing how the laminated structure 100 is irradiated with a line beam (peeling light 216) emitted from the line beam light source 214 of the peeling device 220. For the sake of clarity, the stage 212, the laminated structure 100, and the line beam light source 214 are shown separated from each other in the Z-axis direction in the drawing. The second surface 100 b of the laminated structure 100 is in contact with the stage 212 when the peeling light 216 is irradiated.

  FIG. 8B schematically shows the position of the stage 212 when the peeling light 216 is irradiated. Although not shown in FIG. 8B, the laminated structure 100 is supported by the stage 212.

Examples of the laser device that emits the separation light 216 include a gas laser device such as an excimer laser, a solid-state laser device such as a YAG laser, a semiconductor laser device, and other laser devices. According to the XeCl excimer laser device, laser light having a wavelength of 308 nm can be obtained. If neodymium (Nd) is doped yttrium vanadium tetraoxide (YVO _4), or ytterbium (Yb) uses YVO ₄ doped as lasing medium, a laser beam (fundamental emitted from the laser gain medium Since the wavelength of the (wave) is about 1000 nm, it can be used after being converted into laser light (third harmonic) having a wavelength of 340 to 360 nm by a wavelength conversion element.

  From the viewpoint of suppressing the generation of ash, it is more effective to use the laser light having the wavelength of 308 nm by the excimer laser device than the laser light having the wavelength of 340 to 360 nm. Further, when the release layer is provided, a remarkable effect is exerted in suppressing the generation of ash.

The irradiation of the peeling light 216 can be performed at an energy irradiation density of 50 to 400 mJ/cm ² , for example. The line-beam-shaped separation light 216 has a size that traverses the base 10, that is, a line length (long axis dimension, Y-axis direction size in FIG. 8B) that exceeds the length of one side of the base. The line length can be, for example, 750 mm or more. On the other hand, the line width of the peeling light 216 (short axis dimension, size in the X-axis direction in FIG. 8B) may be, for example, about 0.2 mm. These dimensions are the size of the irradiation region at the interface between the resin film 30 and the base 10. The stripping light 216 can be emitted as a pulsed or continuous wave. The pulsed irradiation can be performed at a frequency of about 200 times per second, for example.

  The irradiation position of the peeling light 216 moves relative to the base 10, and the scanning of the peeling light 216 is executed. In the peeling device 220, the light source 214 that emits peeling light and the optical device (not shown) may be fixed, and the laminated structure 100 may move, or vice versa. In the present embodiment, irradiation of the peeling light 216 is performed while the stage 212 moves from the position shown in FIG. 8B to the position shown in FIG. 8C. That is, the separation light 216 is scanned by the movement of the stage 212 along the X-axis direction.

<Lift off>
FIG. 9A describes a state in which the laminated structure 100 is in contact with the stage 212 after irradiation with the peeling light. While maintaining this state, the distance from the stage 212 to the base 10 is increased. At this time, the stage 212 in this embodiment adsorbs the OLED device portion of the laminated structure 100.

  A drive unit (not shown) holds the base 10 and moves the entire base 10 in the direction of the arrow, so that peeling (lift-off) is performed. The base 10 can move together with the suction stage while being sucked by a suction stage (not shown). The direction of movement of the base 10 does not have to be perpendicular to the first surface 100a of the laminated structure 100, and may be inclined. The movement of the base 10 does not have to be a linear movement, but may be a rotational movement. Further, the base 10 may be fixed by a holding device (not shown) or another stage, and the stage 212 may move upward in the drawing.

  FIG. 9B is a cross-sectional view showing the first portion 110 and the second portion 120 of the laminated structure 100 thus separated. The first portion 110 of the laminated structure 100 includes a plurality of OLED devices 1000 in contact with a stage 212. Each OLED device 1000 has a functional layer region 20 and a plurality of flexible substrate regions 30d of the resin film 30. On the other hand, the second portion 120 of the laminated structure 100 is the base 10.

  The individual OLED devices 1000 supported by the stage 212 can be easily removed from the stage 212, either simultaneously or sequentially, because they are in a disconnected relationship with each other.

  In the above embodiment, each OLED device 1000 is cut and separated before the LLO process, but each OLED device 1000 may be cut and separated after the LLO process. Also, cutting and separating each OLED device 1000 may include dividing the base 10 into corresponding portions.

  FIG. 10 is a sectional view showing a flexible OLED device according to an embodiment of the present disclosure. The functional layer region 20 is supported by the flexible substrate region 30d of the resin film 30 separated from the base 10.

  According to an embodiment of the present disclosure, when a flexible film is used from highly transparent polyimide and PET that transmit ultraviolet light, or a flexible film that has low transparency but is thin (5 to 20 μm in thickness) and transparent to ultraviolet light is used. Even in this case, it is possible to suppress the characteristic deterioration of the functional layer region and the performance deterioration of the gas barrier film due to the ultraviolet rays.

  Embodiments of the present invention provide a method for manufacturing a new flexible OLED device. The flexible OLED device can be widely applied to smartphones, tablet terminals, in-vehicle displays, and small-to-medium-sized to large-sized television devices.

  10... Base, 20... Functional layer region, 20A... TFT layer, 20B... OLED layer, 30... Resin film, 30d... Flexible substrate region of resin film, 30i... Intermediate region of resin film, 40... Gas barrier film, 50... Protective sheet, 100... Laminated structure, 212... Stage, 1000... OLED device

Claims (3)

A functional layer region including a TFT layer and an OLED layer,
A flexible film supporting the functional layer region,
A dielectric multilayer mirror located between the flexible film and the functional layer region,
The flexible OLED device, wherein the reflectance of the dielectric multilayer mirror is relatively lower at a wavelength of 308 nm than at a wavelength of 355 nm. The dielectric multilayer mirror is
Three or more high refractive index layers each having a first refractive index;
Two or more low refractive index layers each having a second refractive index lower than the first refractive index and located between the three or more high refractive index layers;
The flexible OLED device of claim 1, comprising: The flexible OLED device according to claim 1, wherein the TFT layer has a polycrystallized semiconductor layer.

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