JP6885099B2 - Display device manufacturing method and light irradiation device - Google Patents

Description

The present invention relates to a method for manufacturing a display device and a light irradiation device.

Conventionally, a display device (organic EL display device) has been developed in which an organic EL (electroluminescence) element is used as a light emitting element and the light emitted from the light emitting element is used as display light. The applications of such display devices are expanding not only to televisions and desktop monitors, but also to portable electronic devices such as portable laptop computers, mobile phones, portable game machines, electronic readers, and electronic books. Therefore, further weight reduction, miniaturization, and thinning are required.

In such a situation, as a display device member constituting the display device, a display device member using a flexible substrate made of a flexible film is proposed instead of the glass support substrate which has been mainly used so far. Has been done. By using a flexible substrate such as a resin base material instead of the glass support substrate in the display device member, it is possible to make the display device flexible.

When producing such a flexible display device, a release layer (photoheat exchange membrane) and a resin base material (PI layer) are formed in this order on a glass base material, and a thin film transistor (TFT) or the like is formed on the resin base material. After the formation, the peeling layer is irradiated with a laser beam to peel the glass base material from the resin base material (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2015-138895

However, the thickness of the glass base material may be non-uniform in the plane or may vary from glass base material to glass base material. If the thickness of the glass substrate is uneven, the focus of the laser light may deviate from the peeling layer, and the irradiation amount of the laser light applied to the peeling layer may change. In this case, if the amount of laser light irradiation is small, there is a problem that the glass base material is torn when the glass base material is peeled off, and if the amount of laser light irradiation is large, the resin base material is burnt. There was a problem that soot was generated on the resin base material.

The present invention has been made in consideration of such a point, and even if the thickness of the glass base material is uneven, the glass base material can be reliably peeled off from the resin base material, and the display device can be used. An object of the present invention is to provide a method for manufacturing a display device and a light irradiation device that can be manufactured with high productivity.

The present invention is a method for manufacturing a display device, which comprises a glass base material, a peeling layer laminated on the glass base material and decomposed by absorbing light, and a peeling layer laminated on the peeling layer. A step of preparing an intermediate for a display device having a metal layer capable of reflecting the light transmitted through the layer, and linear or linear light from the glass base material side of the intermediate toward the peeling layer. A method for manufacturing a display device, which comprises a step of decomposing the peeling layer by irradiating in a plane shape and peeling the glass base material from the metal layer.

The present invention is a method for manufacturing a display device, wherein the light is a laser beam.

The present invention is a method for manufacturing a display device, wherein the light is a solid-state laser light.

The present invention is a light irradiation device, in which a glass base material, a release layer laminated on the glass base material and decomposed by absorbing light, and the release layer laminated on the release layer are provided. A stage on which an intermediate for a display device including a metal layer capable of reflecting the transmitted light is placed, and the glass base material side of the intermediate placed on the stage toward the release layer. The light irradiation device is provided with a light source unit that decomposes the release layer by irradiating the light linearly or in a planar manner.

The present invention is a light irradiation device characterized in that the light is laser light.

The present invention is a light irradiation device characterized in that the light is a solid-state laser light.

The present invention is a light irradiation device characterized in that the light source unit includes a light source that irradiates the light and a diffractive optical element that shapes the light from the light source into a linear or planar shape.

According to the present invention, even if the thickness of the glass base material is uneven, the glass base material can be reliably peeled off from the resin base material, and the display device can be manufactured with high productivity.

FIG. 1 is a cross-sectional view showing a display device forming substrate used in a method for manufacturing a display device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing a display device manufactured by the method for manufacturing a display device according to an embodiment of the present invention. 3 (a)-(c) are cross-sectional views showing a method of manufacturing a substrate for forming a display device. 4 (a)-(e) are cross-sectional views showing a method of manufacturing a display device according to an embodiment of the present invention. 5 (a)-(c) are cross-sectional views showing a method of manufacturing a display device according to an embodiment of the present invention. 6 (a)-(d) are cross-sectional views showing a method of manufacturing a display device according to an embodiment of the present invention. FIG. 7 is a schematic perspective view showing a light irradiation device according to an embodiment of the present invention. FIG. 8 is a schematic cross-sectional view showing a light source unit of a light irradiation device according to an embodiment of the present invention. 9 (a)-(c) are cross-sectional views showing a modified example (modified example 1) of a method for manufacturing a display device. 10 (a)-(b) is a cross-sectional view showing a modified example (modified example 1) of a method for manufacturing a display device. 11 (a)-(c) are cross-sectional views showing a modified example (modified example 2) of a method for manufacturing a substrate for forming a display device. 12 (a)-(b) are cross-sectional views showing a modified example (modified example 2) of a method for manufacturing a substrate for forming a display device. 13 (a)-(c) are cross-sectional views showing a modified example (modified example 2) of a method for manufacturing a substrate for forming a display device.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 6. In each of the following figures, the same parts are designated by the same reference numerals, and some detailed description may be omitted.

(Structure of substrate for forming display device)
First, with reference to FIG. 1, an outline of a display device forming substrate used in the method for manufacturing a display device according to the present embodiment will be described. FIG. 1 is a cross-sectional view showing a substrate for forming a display device.

The display device forming substrate 10 shown in FIG. 1 is for manufacturing a display device 20 (see FIG. 2) described later. The display device forming substrate 10 is a metal that is laminated on the glass base material 11, the release layer 12 laminated on the glass base material 11, and the release layer 12 and can reflect the laser beam transmitted through the release layer 12. It includes a layer 13.

Of these, the glass base material 11 supports the entire display device forming substrate 10 and is made of a flat plate-shaped member. As the glass base material 11, a material capable of transmitting laser light can be used, and for example, transparent glass such as non-alkali glass, quartz glass, and Pyrex (registered trademark) can be used. _{The thickness t 1} of the glass base material 11 can be set in consideration of the strength of the material, handling suitability, and the like, and can be appropriately set in the range of, for example, about 150 μm or more and 900 μm or less. The glass size of the glass base material 11 is arbitrary, and for example, a G6 size (1800 mm × 1500 mm) glass base material 11 can be used.

The release layer 12 is composed of a flat layer (adhesive layer) directly formed on the glass base material 11. The release layer 12 adheres the glass base material 11 and the metal layer 13 in the manufacturing process of the display device forming substrate 10 described later, and attaches the glass base material 11 to the metal layer 13 in the subsequent manufacturing process of the display device 20. It is to be peeled off from.

As the release layer 12, a layer that generates heat by absorbing laser light, is decomposed, and the adhesion is reduced or disappears is used. Further, as the release layer 12, a layer having good adhesion to the material of the glass base material 11 is used. The release layer 12 is a release material such as amorphous silicon or polyimide having a property of absorbing light composed of laser light of a specific wavelength such as a solid-state laser having a wavelength of 355 nm (for example, BREWER BOND series manufactured by Brewer Science, Inc.). , UPIA series (product name) manufactured by Ube Kosan Co., Ltd., Uimide series (product name) manufactured by Unitika Co., Ltd., Optomer AL series (product name) manufactured by JSR Co., Ltd., TZNR-A manufactured by Tokyo Oka Kogyo Co., Ltd. Series (product name)) can be used. In particular, the release layer 12 preferably contains polyimide. As a result, the release layer 12 can efficiently absorb the laser beam. Further, the thickness t ₂ of the release layer 12 can be appropriately set in the range of, for example, about 50 nm or more and 150 nm or less. By setting the thickness t ₂ of the release layer 12 to 50 nm or more, the adhesion between the glass base material 11 and the metal layer 13 can be improved when the display device forming substrate 10 is manufactured. _{Further, by setting the thickness t 2} of the release layer 12 to 150 nm or less, the cost of the release layer 12 can be reduced.

As will be described later, the release layer 12 may be formed on a glass substrate 11 by a die coating method, an inkjet method, a spray coating method, a plasma CVD method or a thermal CVD method, a capillary coating method, a slit and spin method, a central dropping method, or the like. It is a dried product obtained by coating and forming according to the above method. The release layer 12 made of such a coating layer can improve the flatness as a whole, and can form the release layer 12 with high dimensional accuracy. In the present embodiment, the release layer 12 is formed by applying a polyimide precursor on a glass base material 11 by a spin method and drying it.

The metal layer 13 is for protecting the resin base material 22 described later, which is formed on the display device forming substrate 10. Specifically, the metal layer 13 is formed by the release layer 12 when the resin base material 22 and the release layer 12 are separated from each other and the release layer 12 is modified by laser light in the manufacturing process of the display device 20 described later. By reflecting the laser light that has passed through the release layer 12 without being absorbed, it plays a role of protecting the resin base material 22 from the laser light. That is, the metal layer 13 reflects the laser beam to modify the release layer 12 without damaging the resin base material 22.

Examples of the laser used for modifying the release layer 12 include an excimer laser (wavelength 248 nm, 308 nm), a solid-state laser such as a YAG laser (wavelength 355 nm, 532 nm, 1064 nm), and a CO _{2 laser (wavelength 10640 nm).} Therefore, the metal layer 13 preferably has reflectivity to the laser used for modifying the release layer 12. In particular, the metal layer 13 preferably has reflectivity to an excimer laser, a solid-state laser, and a CO _{2 laser.} In the present embodiment, as will be described later, a solid-state laser can be preferably used as the laser for modifying the release layer 12. Examples of the solid-state laser include a titanium sapphire laser and its second high wavelength and third high wavelength, in addition to the YAG laser. In the following, a case where a solid-state laser is used as the laser will be described as an example.

Further, the metal layer 13 shields the gas from the release layer 12 side when the release layer 12 is modified in the manufacturing process of the display device 20, and prevents heat diffusion from occurring in the resin base material 22. Play a role. Therefore, the metal layer 13 has good reflectivity of the above-mentioned laser light, shielding of gas from the peeling layer 12, and good adhesion to the peeling layer 12, or oxidation resistance, moisture resistance, or acid resistance. Is used.

As will be described later, such a metal layer 13 is formed on the peeling layer 12 by a method such as a sputtering method, a vapor deposition method, an ion plating method, or a CVD method. The metal layer 13 can be, for example, a layer having a reflectance of 60% or more of laser light. Examples of the material of the metal layer 13 include metal materials such as chromium, nickel, molybdenum, titanium, aluminum, silver, palladium, copper, tungsten, and alloys containing at least one of them. In particular, the metal layer 13 preferably contains a molybdenum alloy, whereby the laser light transmitted through the release layer 12 can be efficiently reflected. Specifically, the metal layer 13 is preferably made of an alloy containing molybdenum, nickel and titanium, or an alloy containing molybdenum and niobium. Further, the thickness t ₃ of the metal layer 13 can be appropriately set so that the reflectance of the laser light is 60% or more, and is preferably about 30 nm or more and 150 nm or less, for example. By setting the thickness t ₃ of the metal layer 13 to 30 nm or more, the laser beam can be reliably reflected. _{Further, by setting the thickness t 3} of the metal layer 13 to 150 nm or less, the cost of the metal layer 13 can be reduced. The molybdenum alloy has a high reflectance of laser light, and the difference in reflectance depending on the thickness is small. As a result, when the metal layer 13 is made of a molybdenum alloy, the reflectance of the laser light can be increased regardless of the thickness of the metal layer 13, and the thickness of the metal layer 13 can be reduced. Therefore, the cost of the metal layer 13 can be reduced. Further, since the molybdenum alloy has good adhesion to polyimide, when the metal layer 13 is made of molybdenum alloy and the release layer 12 is made of polyimide, when the display device forming substrate 10 is manufactured, The adhesion between the release layer 12 and the metal layer 13 can be improved.

In the present embodiment, as shown in FIG. 1, the release layer 12 and the metal layer 13 cover the entire area of the glass base material 11, but the present invention is not limited to this, and the metal layer 13 will be described later. As long as the entire area of the resin base material 22 can be covered, the peripheral edge portion 12e of the release layer 12 and the peripheral edge portion 13e of the metal layer 13 may be retracted inward from the peripheral edge portion 11e of the glass base material 11. That is, the planar shape of the release layer 12 may be smaller than the planar shape of the glass base material 11 over the entire circumference.

(Display device configuration)
Next, with reference to FIG. 2, the outline of the display device manufactured by the method of manufacturing the display device according to the present embodiment will be described. FIG. 2 is a cross-sectional view showing a display device according to the present embodiment. In this display device, a plurality of organic EL elements 24 and the like, which will be described later, are arranged on the display device forming substrate 10 described above, the glass base material 11 and the release layer 12 are removed, and then the individual organic EL elements 24 are cut. It was formed by individualizing.

The display device 20 shown in FIG. 2 is a support base material 21, a metal layer 13 constituting the above-mentioned display device forming substrate 10 laminated on the support base material 21, and a resin arranged on the metal layer 13. The base material 22, the thin film transistor (TFT) 23 arranged on the resin base material 22, the organic EL element (element) 24 arranged on the resin base material 22, and the sealing arranged on the organic EL element 24. It includes a resin (TFE) 25.

Of these, the support base material 21 supports the entire display device 20 and is made of a flexible film. The supporting base material 21 is attached to the metal layer 13 with an adhesive, as will be described later. As the supporting base material 21, for example, polyethylene terephthalate can be used. The thickness of the support base material 21 can be set in consideration of the strength of the material, handling suitability, etc., and can be appropriately set in the range of, for example, about 50 μm or more and 250 μm or less.

The metal layer 13 constitutes the above-mentioned display device forming substrate 10, and is interposed between the support base material 21 and the resin base material 22. The structure of the metal layer 13 is the same as that of the metal layer 13 of the display device forming substrate 10 described above, and detailed description thereof will be omitted here.

The resin base material 22 supports the thin film transistor 23, the organic EL element 24, and the like in the manufacturing process of the display device 20 described later, and is composed of a flexible flat layer directly formed on the metal layer 13. .. As will be described later, the resin base material 22 may be subjected to a die coating method, an inkjet method, a spray coating method, a plasma CVD method or a thermal CVD method, a capillary coating method, a slit and spin method, a central dropping method, or the like on the metal layer 13. It is coated and formed by the method. It is preferable that the resin base material 22 is made of a material that is more flexible than the glass base material 11 described above and has excellent heat resistance. As the resin base material 22, for example, colored opaque or transparent polyimide (for example, UPIA-ST (product name) manufactured by Ube Industries, Ltd.) can be used. The thickness of the resin base material 22 can be set in consideration of the strength of the material, handling suitability, and the like, and can be appropriately set in the range of, for example, about 5 μm or more and 20 μm or less.

The thin film transistor 23 is for driving the organic EL element 24, and controls the voltage applied to the first electrode 26 and the second electrode 28, which will be described later, of the organic EL element 24.

The organic EL element 24 is electrically connected to the thin film transistor 23. As shown in FIG. 2, the organic EL element 24 includes a first electrode (reflection electrode) 26 arranged on the resin base material 22, an organic light emitting layer 27 arranged on the first electrode 26, and an organic light emitting layer. It has a second electrode (transparent electrode) 28 arranged on 27. Here, an example in which the first electrode 26 constitutes an anode and the second electrode 28 constitutes a cathode will be described. However, the polarities of the first electrode 26 and the second electrode 28 are not particularly limited.

As will be described later, the first electrode 26 is formed on the resin base material 22 by a method such as a sputtering method, a vapor deposition method, an ion plating method, or a CVD method. As the material of the first electrode 26, it is preferable to use a material capable of efficiently injecting holes. Examples of the material of the first electrode 26 include metal materials such as aluminum, chromium, molybdenum, tungsten, copper, silver or gold and alloys thereof.

As will be described later, the organic light emitting layer 27 is formed on the first electrode 26 by a vapor deposition method, a nozzle coating method in which a coating liquid is applied from a nozzle, or a printing method such as an inkjet. The organic light emitting layer 27 preferably contains a fluorescent organic substance configured to emit white light by applying a predetermined voltage, and for example, a quinolinol complex, an oxazole complex, various laser dyes, and polyparaphenylene. Examples include vinylene.

As will be described later, the second electrode 28 is formed on the organic light emitting layer 27 by a method such as a sputtering method, a vapor deposition method, an ion plating method, or a CVD method. As the material of the second electrode 28, it is preferable to use a material that is easy to inject electrons and has good light transmission. Examples of the material of the second electrode 28 include lithium oxide, cesium carbonate and the like.

The light emitted by the organic EL element 24 is taken out to the side opposite to the side where the resin base material 22 is located. That is, the light from the organic EL element 24 is taken out from above the sealing resin 25. As described above, the display device 20 in the present embodiment is a so-called top emission type display device.

The sealing resin 25 is for sealing the organic EL element 24 and protecting the organic EL element 24. As will be described later, the sealing resin 25 is subjected to a die coating method, an inkjet method, a spray coating method, a plasma CVD method or a thermal CVD method, or a capillary coating on the resin base material 22, the thin film transistor 23, the first electrode 26, and the second electrode 28. It is coated and formed by a method such as a method, a slit and spin method, or a central dropping method. As the sealing resin 25, it is preferable to use a material having more flexibility than the glass base material 11 described above. As the sealing resin 25, for example, a silicone resin or an acrylic resin can be used. The thickness of the sealing resin 25 (distance from the upper surface of the resin base material 22 in FIG. 2 to the upper surface of the sealing resin 25) can be set in consideration of the strength of the material, handling suitability, etc., for example, 1 μm or more. It can be appropriately set within a range of about 50 μm or less.

In the present embodiment, as shown in FIG. 2, an example in which the display device 20 is a top emission type is shown, but the present invention is not limited to this, and the display device 20 may be a so-called bottom emission type. Good.

(Manufacturing method of substrate for forming display device)
Next, the method for manufacturing the above-mentioned display device forming substrate will be described with reference to FIGS. 3 (a) and 3 (c). 3 (a)-(c) are cross-sectional views showing a method of manufacturing a substrate for forming a display device.

First, as shown in FIG. 3A, a glass base material 11 made of a flat plate-shaped member is prepared. At this time, for example, a G6 size (1800 mm × 1500 mm) glass base material 11 is prepared. As the glass base material 11, for example, non-alkali glass, quartz glass, and Pyrex (registered trademark) can be used.

Next, as shown in FIG. 3B, the release layer 12 is directly laminated on the glass base material 11 to form the glass base material 11. As the release layer 12, as described above, a layer that generates heat by absorbing laser light, is decomposed, and the adhesion is reduced or disappears is used. For example, as the release layer 12, a release material such as amorphous silicon or polyimide having a property of absorbing a specific wavelength (for example, a wavelength of 355 nm) such as a solid-state laser can be used. In particular, the release layer 12 preferably contains polyimide.

The release layer 12 is formed by, for example, a die coating method, an inkjet method, a spray coating method, a capillary coating method, a slit and spin method, or a central dropping method. Therefore, as compared with the case where a foam-type adhesive film, tape or the like is attached on the glass base material 11, there is no possibility that the film, tape or the like has waviness or uneven thickness of the adhesive or the like, and the release layer 12 is flat. You can improve your sex. In this way, the release layer 12 is formed on the glass base material 11. In the present embodiment, for the release layer 12, for example, the rotation speed of the glass base material 11 is set to 2500 rpm, a polyimide precursor is applied onto the glass base material 11 by a spin method, and then a vacuum drying device is used. It is formed by drying with (VCD) under a reduced pressure condition of 25 Pa and firing at 300 ° C. for 5 minutes.

Subsequently, as shown in FIG. 3C, the metal layer 13 is laminated on the release layer 12. The metal layer 13 is for protecting the resin base material 22 formed on the display device forming substrate 10 in the subsequent process. As the metal layer 13, a metal layer 13 having good reflectivity of laser light and good shielding property of gas from the release layer 12 side is used. The metal layer 13 may be made of a metal material such as chromium, molybdenum, titanium, aluminum, silver, copper, nickel, palladium, tungsten or an alloy containing at least one of them. In particular, the metal layer 13 preferably contains a molybdenum alloy. Specifically, the metal layer 13 is preferably made of an alloy containing molybdenum, nickel and titanium, or an alloy containing molybdenum and niobium. The metal layer 13 is formed on the release layer 12 by a method such as a sputtering method, a vapor deposition method, an ion plating method, or a CVD method. Therefore, the thin-film metal layer 13 can be formed uniformly and flatly.

In this way, the display device forming substrate 10 shown in FIG. 1 is obtained.

(Manufacturing method of display device)
Next, a method of manufacturing the display device according to the present embodiment will be described with reference to FIGS. 4 (a)-(e), 5 (a)-(c) and 6 (a)-(d). 4 (a)-(e), 5 (a)-(c) and 6 (a)-(d) are cross-sectional views showing a method of manufacturing a display device according to the present embodiment.

First, for example, the display device forming substrate 10 is manufactured by the method shown in FIGS. 3 (a)-(c) (FIG. 4 (a)).

Next, the resin base material 22 is arranged on the metal layer 13 of the display device forming substrate 10 (FIG. 4B). As the resin base material 22, one having more flexibility than the glass base material 11 and having excellent heat resistance may be used. For example, as the resin base material 22, colored opaque or transparent polyimide can be used. The resin base material 22 is formed on the metal layer 13 by a method such as a die coating method, an inkjet method, a spray coating method, a plasma CVD method or a thermal CVD method, a capillary coating method, a slit and spin method, or a central dropping method. ..

Next, the thin film transistor 23 is placed on the resin base material 22 (FIG. 4 (c)). At this time, although not shown, a plurality of thin film transistors 23, each of which corresponds to each display device 20, are arranged on the resin base material 22. In this way, the first intermediate 20a of the display device 20 is formed. After the plurality of thin film transistors 23 are arranged on the resin base material 22, the first intermediate 20a of the display device 20 is cut into, for example, half the size in a plan view by a cutting device (not shown). To.

Next, the organic EL element 24 is arranged on the resin base material 22 (FIG. 4 (d)). At this time, although not shown, a plurality of organic EL elements 24, each of which corresponds to each display device 20, are arranged on the resin base material 22. Each of the organic EL elements 24 has a first electrode 26 arranged on the resin base material 22, an organic light emitting layer 27 arranged on the first electrode 26, and a second electrode arranged on the organic light emitting layer 27. It has 28 and. In this case, first, the first electrode 26 is formed on the resin base material 22. A material capable of efficiently injecting holes is used for the first electrode 26. For example, as the first electrode 26, a metal material such as aluminum, chromium, molybdenum, tungsten, copper, silver or gold and an alloy thereof can be used. The first electrode 26 is formed on the resin base material 22 by a method such as a sputtering method, a vapor deposition method, an ion plating method, or a CVD method. At this time, the first electrode 26 of the organic EL element 24 is electrically connected to the thin film transistor 23.

Next, the organic light emitting layer 27 is formed on the first electrode 26. As the organic light emitting layer 27, a layer containing a fluorescent organic substance configured to emit white light by applying a predetermined voltage is used. For example, as the organic light emitting layer 27, a quinolinol complex, an oxazole complex, various laser dyes, polyparaphenylene vinylene and the like can be used. The organic light emitting layer 27 is formed on the first electrode 26 by a vapor deposition method, a nozzle coating method in which a coating liquid is applied from a nozzle, or a printing method such as an inkjet.

Next, the second electrode 28 is formed on the organic light emitting layer 27. A material that is easy to inject electrons and has good light transmission is used for the second electrode 28. For example, as the second electrode 28, lithium oxide, cesium carbonate or the like can be used. The second electrode 28 is formed on the organic light emitting layer 27 by a method such as a sputtering method, a vapor deposition method, an ion plating method, or a CVD method. In this way, the organic EL element 24 is arranged on the resin base material 22.

Next, the organic EL element 24 arranged on the resin base material 22 is sealed with the sealing resin 25 (FIG. 4 (e)). As the sealing resin 25, a material having a flexibility more than that of the glass base material 11 described above may be used. For example, as the sealing resin 25, a silicone resin or an acrylic resin is used. The sealing resin 25 is formed on the resin base material 22, the thin film transistor 23, the first electrode 26 and the second electrode 28 by a die coating method, an inkjet method, a spray coating method, a plasma CVD method or a thermal CVD method, a capillary coating method, a slit and a spin. It is formed by a method such as a method or a central dropping method. In this way, the organic EL element 24 is covered with the sealing resin 25.

Next, the temporary support base material 29 is placed on the sealing resin 25 (FIG. 5A). The temporary support base material 29 temporarily supports the first intermediate 20a of the display device 20 manufactured in the manufacturing process of the display device 20. A flexible film is used as the temporary support base material 29. For example, as the temporary support base material 29, a film made of polyethylene terephthalate can be used. The temporary support base material 29 may be attached on the sealing resin 25 with an adhesive. The thickness of the temporary support base material 29 can be set in consideration of the strength of the material, handling suitability, etc., and can be appropriately set in the range of, for example, about 50 μm or more and 250 μm or less. In this way, the second intermediate 20b of the display device 20 on which the temporary support base material 29 is arranged is produced.

Subsequently, the second intermediate 20b of the produced display device 20 is inverted, and the glass base material 11 is peeled from the metal layer 13. At this time, laser light L such as a YAG laser is irradiated from the glass substrate 11 side (FIG. 5 (b)). The laser light L is irradiated linearly or planarly from, for example, a light irradiation device 60 described later, and the laser light L is uniformly scanned in the plane of the second intermediate 20b. The laser beam L irradiated in this way passes through the transparent glass base material 11 and reaches the release layer 12. As described above, the release layer 12 loses or loses its adhesive force by being modified or decomposed. Therefore, the adhesive force of the release layer 12 is reduced or eliminated by being modified or decomposed by the laser beam L, and the glass base material 11 is separated from the metal layer 13 (FIG. 5 (c)).

On the other hand, a metal layer 13 is provided on the surface of the release layer 12 opposite to the glass base material 11. Therefore, the laser beam L transmitted through the release layer 12 is reflected by the metal layer 13 and returned to the glass base material 11. Therefore, the laser light L does not reach the resin base material 22, and the laser light L transmitted through the release layer 12 does not adversely affect the resin base material 22. The metal layer 13 maintains a state of being in close contact with the resin base material 22.

Next, the support base material 21 that supports the display device 20 is placed on the metal layer 13 from which the glass base material 11 has been peeled off (FIG. 6A). As the support base material 21, a film having a flexibility more than that of the glass base material 11 described above is used. For example, as the supporting base material 21, a film made of polyethylene terephthalate can be used. The support base material 21 may be attached to the metal layer 13 with an adhesive. In this way, the second intermediate 20b of the display device 20 is supported by the support base material 21.

Next, the second intermediate 20b of the display device 20 is inverted (FIG. 6 (b)).

Then, the temporary support base material 29 is peeled off from the sealing resin 25 (FIG. 6 (c)). After the temporary support base material 29 is peeled from the sealing resin 25, the second intermediate 20b of the display device 20 is cut and individualized for each display device 20 by a cutting device (not shown). (Fig. 6 (d)).

Through the above series of steps, the display device 20 shown in FIG. 2 can be obtained (FIG. 6 (d)).

Next, with reference to FIGS. 7 and 8, a step of irradiating the laser beam L from the glass base material 11 side in order to separate the glass base material 11 from the metal layer 13 (FIG. 5 (b)) will be further described. To do. FIG. 7 is a schematic perspective view showing a light irradiation device according to an embodiment of the present invention, and FIG. 8 is a schematic cross-sectional view showing a light source unit of the light irradiation device.

As shown in FIG. 7, the light irradiation device 60 includes a stage 61 and a light source unit 64 arranged above the stage 61.

Of these, the second intermediate 20b for the display device 20 is placed on the stage 61. The stage 61 has a flat surface 61a facing the light source unit 64 side, and the second intermediate 20b is placed on the surface 61a. The second intermediate 20b contains a glass base material 11, a release layer 12, a metal layer 13, a resin base material 22, a thin film transistor 23, an organic EL element 24, and a sealing resin 25 in this order from the upper side. And a temporary support base material 29. Further, the stage 61 is movable in a horizontal plane, whereby the second intermediate 20b mounted on the stage 61 can be moved in the horizontal direction.

The light source unit 64 irradiates light linearly or planarly (linearly in FIG. 7) from the glass base material 11 side toward the peeling layer 12 in order to separate the glass base material 11 from the metal layer 13. is there. The light source unit 64 includes a light source 62 that irradiates light, and a diffractive optical element 63 that shapes the light from the light source 62 into a linear or planar shape.

Of these, the light source 62 irradiates laser light L, which is straight light, and more specifically, irradiates solid-state laser light L (wavelength 355 nm, 532 nm, 1064 nm) such as a YAG laser.

Further, the diffractive optical element 63 shapes the laser beam L, which is straight light, into a linear or planar shape, and as shown in FIG. 8, a plurality of diffracting optical elements 63 projecting from the main body portion 63a and the main body portion 63a, respectively. It has a protrusion 63b of the above. The pitch p of the plurality of protrusions 63b is, for example, 0.1 μm or more and 10 μm. In this way, by using the diffractive optical element 63 to make the laser beam L linear or planar toward the second intermediate 20b, it is possible to irradiate the laser beam L over a wide range while narrowing it down to a specific range. it can. This makes it possible to efficiently carry out the work of disassembling the release layer 12 and peeling the glass base material 11 from the metal layer 13.

When irradiating the second intermediate 20b with the laser beam L using the light irradiation device 60, first, the second intermediate 20b is placed on the stage 61 on the light irradiation device 60. Next, the laser beam L is irradiated from the light source 62 of the light source unit 64. The laser beam L is shaped linearly or planarly (linearly in FIG. 7) in the diffractive optical element 63, and reaches on the second intermediate 20b. During this time, by moving the second intermediate 20b in the horizontal direction using the stage 61, the laser beam L is uniformly scanned in the plane of the second intermediate 20b. The laser beam L irradiated on the second intermediate 20b passes through the transparent glass base material 11 and reaches the release layer 12. Subsequently, the release layer 12 is decomposed by absorbing the laser beam L, and the adhesion is reduced or disappears. In this way, the glass base material 11 can be peeled from the metal layer 13 in the next step (FIG. 5 (c)).

By the way, in general, a solid-state laser (wavelength 355 nm) such as a YAG laser has an advantage that the running cost of the irradiation device is low as compared with an excimer laser (wavelength 308 nm), but has a problem that the depth of focus is narrow. For example, the depth of focus of the excimer laser light is about 100 μm, whereas the depth of focus of the solid-state laser light is about 10 μm. Therefore, especially when solid-state laser light is used as the laser light L, the focus of the laser light L is the thickness from the release layer 12 due to the non-uniform thickness of the glass base material 11 and the temporary support base material 29. It may be displaced in the direction, making it difficult to disassemble the release layer 12. On the other hand, according to the present embodiment, since the metal layer 13 reflects the laser light L transmitted through the release layer 12, the release layer 12 can be decomposed by the light reflected by the metal layer 13. It is possible to prevent the release layer 12 from being unable to be decomposed due to insufficient irradiation of the laser beam L. As a result, the glass base material 11 can be reliably peeled off from the metal layer 13. As a result, it becomes possible to use a solid-state laser light having a narrow depth of focus as the laser light L, and even in this case, the laser light L can be absorbed into the peeling layer 12 and the peeling layer 12 can be reliably decomposed. .. By using the solid-state laser light as the laser light L in this way, the running cost of the light irradiation device 60 can be suppressed.

Further, by using the diffractive optical element 63, it becomes easier to control the light distribution of the laser light L on the second intermediate 20b as compared with the case where a diffuser plate is used, for example. As a result, it is possible to reduce the variation of the focal point of the laser beam L in the thickness direction in the second intermediate 20b. As a result, it becomes possible to use a solid-state laser beam having a narrow depth of focus as the laser beam L, and the running cost of the light irradiation device 60 can be suppressed.

As described above, according to the present embodiment, the release layer 12 is decomposed by absorbing the laser light L, and the metal layer 13 can reflect the laser light L transmitted through the release layer 12. Thereby, in the manufacturing process of the display device 20, the glass base material 11 can be surely peeled from the metal layer 13, and when the peeling layer 12 is heated by the laser light L, the resin base material 22 is separated from the laser light L. Can be protected. As a result, it is possible to suppress the tearing of the glass base material 11 or the generation of soot on the resin base material 22. That is, in consideration of the uneven thickness of the glass base material 11, the focal point of the laser beam L can be set so as to surely reach the release layer 12. In this case, even if the focus of the laser beam L is shifted to the resin substrate 22 side due to the uneven thickness of the glass substrate 11, the laser beam L is reflected by the metal layer 13. As a result, the resin base material 22 is protected by the metal layer 13, and the problem that the laser beam L reaches the resin base material 22 is prevented.

Further, since the focal point of the laser beam L surely reaches the peeling layer 12, the peeling layer 12 can be decomposed without damaging the fragile element such as the organic EL element 24, and the glass base material 11 can be reliably removed. it can.

In particular, according to the present embodiment, the release layer 12 is decomposed by irradiating the release layer 12 with the laser beam L linearly or in a planar manner from the side of the glass substrate 11, and the glass substrate 11 is decomposed. It peels off from the metal layer 13. As a result, the laser light L can be efficiently irradiated on the second intermediate 20b, so that the work of decomposing the release layer 12 using the laser light L can be efficiently performed in a short time, and as a result, the display device. The productivity of 20 can be increased.

Further, according to the present embodiment, since the diffractive optical element 63 shapes the laser light L from the light source 62 into a linear or planar shape, the laser light L can be narrowed down to a specific range and irradiated over a wide range. .. As a result, the work of decomposing the release layer 12 and peeling the glass base material 11 from the metal layer 13 can be efficiently performed. Further, since it becomes easy to control the light distribution of the laser light L on the second intermediate body 20b, it becomes possible to use a solid-state laser light having a narrow depth of focus as the laser light L.

Further, according to the present embodiment, the laser light L is used as the light emitted from the light source unit 64. Since the laser light L has a strong light irradiation intensity and the same wavelength, the release layer 12 can be stably decomposed and the glass base material 11 can be reliably separated from the metal layer 13.

Further, according to the present embodiment, the solid-state laser light L is used as the light emitted from the light source unit 64. As a result, the running cost of the light irradiation device 60 can be suppressed, and the manufacturing cost of the display device 20 can be reduced.

Further, according to the present embodiment, after the glass base material 11 is peeled from the metal layer 13, the support base material 21 that supports the display device 20 is arranged on the metal layer 13 from which the glass base material 11 has been peeled off. .. By arranging the support base material 21 on the metal layer 13 with the metal layer 13 left in this way, it is not necessary to separately provide a step of removing the metal layer 13, so that the display device 20 can be efficiently produced. Is possible.

Further, since the metal layer 13 contains the molybdenum alloy, the laser light L transmitted through the release layer 12 can be efficiently reflected. Further, since the metal layer 13 containing the molybdenum alloy has good gas shielding property from the release layer 12 side, the release layer 12 side is modified when the release layer 12 is modified in the manufacturing process of the display device 20. It is possible to shield the gas from the resin base material 22 and prevent heat diffusion from occurring in the resin base material 22. Further, the metal layer 13 made of a molybdenum alloy can improve the oxidation resistance, moisture resistance and acid resistance of the metal layer 13.

Further, since the release layer 12 contains polyimide, the release layer 12 can efficiently absorb the laser beam L. Therefore, the glass base material 11 can be efficiently peeled from the metal layer 13. Further, since the release layer 12 made of polyimide can efficiently absorb the laser beam L, the thickness t ₂ of the release layer 12 can be reduced, and the cost of the release layer 12 can be reduced. Further, since the polyimide is excellent in heat resistance, since the release layer 12 is made of polyimide, the release layer 12 can be imparted with heat resistance against the heat when the thin film transistor 23 is provided. Therefore, when the thin film transistor 23 is provided on the resin base material 22, problems such as the glass base material 11 being peeled off from the metal layer 13 can be suppressed.

(Modification example 1)
Next, a modification (modification example 1) of the present embodiment will be described. 9 (a)-(c) and 10 (a)-(b) are cross-sectional views showing a modified example of the manufacturing method of the display device. In the manufacturing method of the display device 20 shown in FIGS. 9 (a)-(c) and 10 (a)-(b), a step of removing the metal layer 13 is provided. The configuration is substantially the same as that shown in FIGS. 4 (a)-(e), 5 (a)-(c) and 6 (a)-(d) described above. In FIGS. 9 (a)-(c) and 10 (a)-(b), the same parts as those of the embodiments shown in FIGS. 1 to 6 are designated by the same reference numerals, and detailed description thereof will be omitted.

In the manufacturing method of the display device 20 shown in FIGS. 9 (a)-(c) and 10 (a)-(b), first, FIGS. 4 (a)-(e) and 5 (a)-(c) The second intermediate 20b of the display device 20 is produced in the same manner as in the above. Next, after the glass base material 11 is peeled from the metal layer 13 (see FIG. 5 (c)), the metal layer 13 is removed from the resin base material 22 (FIG. 9 (a)). In this case, for example, after removing the residue of the peeling layer 12 adhering on the metal layer 13 by oxide plasma or oxide solvent stripping (ozone plasma, pyrania cleaning, RCA cleaning) or the like, a caustic potassium hydrogen peroxide solution is used as an etching solution. The metal layer 13 is removed from the resin base material 22 by a selective etching method using or the like.

Next, the support base material 21 that supports the display device 20 is placed on the resin base material 22 from which the metal layer 13 has been removed (FIG. 9 (b)). The support base material 21 may be attached to the resin base material 22 with an adhesive. In this way, the second intermediate 20b of the display device 20 is supported by the support base material 21.

Next, the second intermediate 20b of the display device 20 is inverted (FIG. 9 (c)).

Then, the temporary support base material 29 is peeled off from the sealing resin 25 (FIG. 10 (a)). After the temporary support base material 29 is peeled from the sealing resin 25, the second intermediate 20b of the display device 20 is cut and individualized for each display device 20 by a cutting device (not shown). (Fig. 10 (b)).

The display device 20 can be obtained by the above series of steps (FIG. 10 (b)).

Also in this case, the glass base material 11 can be reliably peeled from the metal layer 13 in the manufacturing process of the display device 20, and when the peeling layer 12 is heated by the laser light L, the resin base material is removed from the laser light L. 22 can be protected. Therefore, it is possible to suppress the tearing of the glass base material 11 or the generation of soot on the resin base material 22.

(Modification 2)
Next, another modification (modification 2) of the present embodiment will be described. 11 to 13 are schematic views showing a modified example (modified example 2) of the manufacturing method of the display device. The modified examples shown in FIGS. 11 to 13 differ in that the liquid crystal element 94 is mainly used instead of the organic EL element 24. In FIGS. 11 to 13, the same parts as those in the embodiments shown in FIGS. 1 to 10 are designated by the same reference numerals, and detailed description thereof will be omitted.

That is, in FIGS. 1 to 10, a case where the display device 20 including the organic EL element 24 is manufactured has been described as an example. However, the present invention is not limited to this, and a liquid crystal display device may be used as the display device 20. 11 to 13 show a method of manufacturing a display device forming substrate for forming such a liquid crystal display device. Hereinafter, a method for manufacturing such a display device forming substrate will be described.

First, as shown in FIGS. 11A and 11B, the color filter layer side intermediate product 80A and the thin film transistor side intermediate product 80B are prepared, respectively.

Of these, as shown in FIG. 11A, the color filter layer side intermediate product 80A is laminated on the first glass base material 81 and the first glass base material 81, and is decomposed by absorbing the laser beam L. The first peeling layer 82 and the first metal layer 83 which are laminated on the first peeling layer 82 and can reflect the laser beam L transmitted through the first peeling layer 82, and are provided on the first metal layer 83. It has a first resin base material 84. Further, the color filter layer 85 is provided on the first resin base material 84, and the first alignment layer 86 is provided on the color filter layer 85. The first release layer 82 and the first metal layer 83 may have substantially the same configurations as the release layer 12 and the metal layer 13 of the display device forming substrate 10 for organic EL described above, respectively.

On the other hand, as shown in FIG. 11B, the thin film transistor side intermediate product 80B is laminated on the second glass base material 87 and the second glass base material 87, and is decomposed by absorbing the laser beam L. A second metal layer 89 laminated on the second peeling layer 88 and capable of reflecting the laser beam L transmitted through the second peeling layer 88, and a second metal layer 89 provided on the second metal layer 89. It has a resin base material 91. Further, the thin film transistor 92 is provided on the second resin base material 91, and the second alignment layer 93 is provided on the thin film transistor 92. The second release layer 88 and the second metal layer 89 may have substantially the same configurations as the release layer 12 and the metal layer 13 of the display device forming substrate 10 for organic EL described above, respectively.

Next, a sealing material containing a UV curable resin and / or a thermosetting agent on one of the intermediate products 80A and 80B of the color filter layer side intermediate product 80A and the thin film transistor side intermediate product 80B (not shown). Is applied, and the liquid crystal is further dropped. Then, the other intermediate products 80B and 80A are bonded together, and the sealing material is cured by ultraviolet rays and / or heat. As a result, the first intermediate 90a having the color filter layer side intermediate product 80A, the thin film transistor side intermediate product 80B, and the liquid crystal element 94 sandwiched between the color filter layer side intermediate product 80A and the thin film transistor side intermediate product 80B. Is obtained (see FIG. 11 (c)).

Subsequently, as shown in FIG. 12A, using the light irradiation device 60 according to the present embodiment, laser light is emitted from the first glass base material 81 side of the first intermediate body 90a toward the first release layer 82. By irradiating L linearly or planarly, the first release layer 82 is decomposed and the first glass base material 81 is separated from the first metal layer 83. After that, the first release layer 82 and the first metal layer 83 remaining on the first resin base material 84 are removed.

Next, as shown in FIG. 11B, the first polarizing plate 95 is attached onto the first resin base material 84 from which the first release layer 82 and the first metal layer 83 have been removed, thereby forming a second intermediate. Body 90b is obtained.

Next, as shown in FIG. 13A, the laser beam L is directed from the second glass base material 87 side of the second intermediate 90b toward the second peeling layer 88 by using the light irradiation device 60 described above. The second release layer 88 is decomposed and the second glass base material 87 is separated from the second metal layer 89 by irradiating the second glass base material 88 in a shape or a plane shape. After that, the second release layer 88 and the second metal layer 89 remaining on the second resin base material 91 are removed.

Then, as shown in FIG. 13B, the second polarizing plate 96 is attached onto the second resin base material 91 from which the second release layer 88 and the second metal layer 89 have been removed. As a result, the first polarizing plate 95, the first resin base material 84, the color filter layer 85, the first alignment layer 86, the liquid crystal element 94, the second alignment layer 93, the thin film transistor 92, and the second resin A display device forming substrate 100 (flexible LCD cell) for a liquid crystal display device in which a base material 91 and a second polarizing plate 96 are sequentially laminated can be obtained.

As described above, in the present modification, the first glass base material 81 and the second glass base material 87 can be reliably peeled from the first metal layer 83 and the second metal layer 89, respectively, and the first peeling can be performed. When the layer 82 and the second release layer 88 are heated by the laser light L, respectively, the first resin base material 84 and the second resin base material 91 can be protected from the laser light L. As a result, it is possible to prevent problems such as tearing of the first glass base material 81 and the second glass base material 87 and generation of soot on the first resin base material 84 and the second resin base material 91. As a result, even if the focus of the laser beam L shifts toward the first resin base material 84 and the second resin base material 91 due to the uneven thickness of the first glass base material 81 and the second glass base material 87, the first The laser beam L is reflected by the metal layer 83 and the second metal layer 89. As a result, the first resin base material 84 and the second resin base material 91 are protected by the first metal layer 83 and the second metal layer 89, and the laser light L is applied to the first resin base material 84 and the second resin base material 91. Reaching defects are prevented.

It is also possible to appropriately combine a plurality of components disclosed in the above-described embodiments and modifications as necessary. Alternatively, some components may be removed from all the components shown in the above embodiments and modifications.

10 Display device forming substrate 11 Glass substrate 12 Peeling layer 13 Metal layer 20 Display device 20b Second intermediate 21 Support substrate 22 Resin substrate 23 Thin film transistor 24 Organic EL element 25 Encapsulating resin 29 Temporary support substrate 60 Light irradiation Equipment 61 Stage 62 Light source 63 Diffractive optical element 64 Light source unit

Claims (7)

It is a manufacturing method of display devices.
A glass substrate, a release layer laminated on the glass substrate and decomposed by absorbing light, and a metal layer laminated on the release layer and capable of reflecting the light transmitted through the release layer. , A resin base material directly formed on the metal layer, a thin film transistor arranged on the resin base material, an organic EL element arranged on the resin base material, and an organic EL element arranged on the organic EL element. The process of preparing an intermediate for a display device having a sealing resin, and
A step of decomposing the peeling layer by irradiating the peeling layer with the light linearly or planarly from the glass base material side of the intermediate and peeling the glass base material from the metal layer. Prepare ,
A method for manufacturing a display device , wherein the peripheral edge portion of the release layer and the peripheral edge portion of the metal layer are recessed inward from the peripheral edge portion of the glass base material. The method for manufacturing a display device according to claim 1, wherein the light is laser light. The method for manufacturing a display device according to claim 2, wherein the light is a solid-state laser light. It is a light irradiation device
A glass substrate, a release layer laminated on the glass substrate and decomposed by absorbing light, and a metal layer laminated on the release layer and capable of reflecting the light transmitted through the release layer. , A resin base material directly formed on the metal layer, a thin film transistor arranged on the resin base material, an organic EL element arranged on the resin base material, and an organic EL element arranged on the organic EL element. A stage on which an intermediate for a display device, including a sealing resin, is placed, and
A light source unit for decomposing the peeling layer by irradiating the peeling layer with the light linearly or planarly from the glass base material side of the intermediate placed on the stage is provided .
A light irradiation device characterized in that the peripheral edge portion of the release layer and the peripheral edge portion of the metal layer are recessed inward from the peripheral edge portion of the glass base material. The light irradiation device according to claim 4, wherein the light is a laser beam. The light irradiation device according to claim 5, wherein the light is a solid-state laser beam. The light source unit according to any one of claims 4 to 6, wherein the light source unit includes a light source that irradiates the light and a diffractive optical element that shapes the light from the light source into a linear or planar shape. The light irradiation device described.

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