JP4954515B2 - Method for manufacturing display device - Google Patents

Description

  The present invention relates to a display device, a manufacturing method thereof, and a manufacturing apparatus thereof, and more particularly to a display device provided on a foldable flexible substrate, a manufacturing method thereof, and a manufacturing apparatus thereof.

  In recent years, research and development of display devices using light-emitting elements have been actively conducted. A display device using a light emitting element does not require a backlight unlike a display device using liquid crystal, and has an advantage that a display can be performed with a high viewing angle. Recently, a film-like display device that can be bent is attracting attention.

  As a method for manufacturing a film-like display device, there are roughly two methods. First, a flexible substrate such as plastic is prepared in advance, and a circuit pattern such as a wiring or a pixel electrode is directly formed on the substrate using a metal material or an insulating material. There are ways to go. Another method is to form a circuit pattern such as wiring and pixel electrodes on a rigid substrate such as glass in advance using a metal material or an insulating material, and then grind and polish only the rigid substrate. There is a method in which a thin film is formed or a rigid substrate and a flexible substrate are replaced.

  However, in the case where a film-like display device is manufactured by directly forming a metal material or an insulating material on a flexible substrate such as plastic, manufacturing conditions are limited due to heat resistance of the substrate. That is, the display device must be manufactured in consideration of various resistances such as heat resistance and strength of the flexible substrate. For example, when a pixel of a display device, a driver circuit, or the like is formed using a thin film transistor (TFT), conditions for heat treatment and the like are limited, and a semiconductor film cannot be sufficiently crystallized. Can't get.

  On the other hand, when a display device is formed on a rigid substrate such as a glass substrate, and then the display device is peeled off from the rigid substrate and transferred to a flexible substrate, a film-like display device is manufactured. There is a problem of disconnection of wiring or the like due to stress applied to the display device, and a problem that makes it difficult to manufacture a large display device because the size of the display device depends on the size of the substrate (here, a glass substrate). .

  In view of the above problems, the present invention can efficiently produce a film-like display device, and a production method capable of forming a large-sized film-like display device, an apparatus for producing a film-like display device, and a film-like device It is an object to provide a display device.

  The display device manufacturing apparatus according to the present invention includes a transport unit that transports a substrate on which an element forming unit constituting the display device is provided, and one surface of the element forming unit is bonded to the first sheet material, A first peeling means for peeling the element forming portion; a second peeling means for peeling the element forming portion from the first sheet material by bonding the other surface of the element forming portion to the second sheet material; It is characterized by having processing means for forming a pixel portion in the element formation portion and sealing means for sandwiching and sealing the processed element formation portion between the second sheet material and the third sheet material.

  Further, as another configuration of the display device manufacturing apparatus of the present invention, a transport means for transporting a substrate provided with an element forming portion constituting the display device, and a first supply in which a first sheet material is wound. A first peeling means for bonding one surface of the roll and the element forming portion to the first sheet material, and peeling the element forming portion from the substrate; and a second wound around the second sheet material The supply roll, the second surface of the element forming portion are bonded to the second sheet material, the second peeling means for peeling the element forming portion from the first sheet material, and the pixel portion is formed in the element forming portion Processing means, a third supply roll around which the third sheet material is wound, and a sealing means for sandwiching and sealing the processed element forming portion between the second sheet material and the third sheet material And a recovery roll for winding up the sealed display device It is. In the present invention, in the above configuration, as a method of sealing the processed element forming portion with the second sheet material and the third sheet material, the third sheet material is supplied while being extruded in a heated and melted state. It can be sealed.

  The display device manufacturing apparatus of the present invention can also be applied to the case where, in the above configuration, the display device is formed by connecting element forming portions constituting the display device provided on a plurality of different substrates. . In this case, the arrangement of the plurality of substrates is accurately adjusted by the control means before the element forming portion provided on the substrate is peeled off. Further, when arranging the substrates, the substrates may be bonded to each other.

  In the above configuration, the processing means is means for forming a pixel portion. As used herein, the pixel portion may be anything that constitutes a pixel portion such as a conductive film such as a wiring or an electrode, an insulating film such as an interlayer insulating film or a protective film, a light emitting layer such as an EL element, or a liquid crystal. But included. In addition, a conductive film such as a wiring connecting the driver circuit portion and the like provided in the periphery of the pixel region and the pixel portion, an insulating film covering the wiring, and the like can be formed by the processing means. As processing means, various printing methods such as a droplet discharge method, a screen printing method or a gravure printing method, or an atmospheric pressure plasma apparatus can be used. The droplet discharge method is a method of selectively discharging (jetting) droplets (also referred to as dots) of a composition containing a material such as a conductor or an insulator to form a pattern at an arbitrary place. Depending on the method, it is also called an inkjet method. Moreover, the sealing means has at least two rollers provided to face each other.

  In the method for manufacturing a display device of the present invention, a release layer is formed over a substrate, an element formation portion that forms part of the display device is formed over the release layer, and an opening is formed in the element formation portion. Is exposed, an etching agent is introduced into the opening, the peeling layer is removed, one surface of the element forming portion is adhered to the first sheet material, and the element forming portion is peeled off from the substrate. The other surface of the element is adhered to the second sheet material, the element forming portion is peeled from the first sheet material, the pixel portion is formed in the element forming portion using the processing means, and one surface of the element forming portion is formed. Is bonded to a third sheet material and sealed. In other words, a part of an element forming portion that constitutes a display device that requires heat treatment or the like is formed on a rigid substrate in advance, and then the remaining portion that constitutes the display device after being peeled and provided on a flexible substrate Form.

  In addition, as a different structure of the method for manufacturing the display device of the present invention, a separation layer is formed over a substrate, a base insulating film is formed over the separation layer, and a channel region and a source or drain region formed over the base insulating film are included. A semiconductor film; a gate electrode formed above the channel region of the semiconductor film via a gate insulating film; an interlayer insulating film formed to cover the gate electrode; and a source of the semiconductor film formed on the interlayer insulating film Or a source or drain electrode and wiring electrically connected to the drain region, a pixel electrode electrically connected to one of the source or drain electrode, and an insulating film formed so as to cover an end of the pixel electrode. An element forming portion is formed, an opening reaching the peeling layer is formed in the insulating film, the interlayer insulating film, the gate insulating film, and the base insulating film to expose the peeling layer, and an etching agent is introduced into the opening. Then, the peeling layer is removed, the first sheet material is adhered to one surface of the element forming portion, the element forming portion is peeled from the substrate, and the second sheet material is peeled from the other surface of the element forming portion. The element forming portion is peeled off from the first sheet material, the light emitting layer and the counter electrode are formed on the pixel electrode using the processing means, the protective film is formed on the counter electrode, and the surface of the protective film And a third sheet material is adhered and sealed.

  Further, in the above structure according to the present invention, the base insulating film is formed over the peeling layer provided over the substrate before performing the peeling treatment, and the semiconductor film including the channel region and the source or drain region formed over the base insulating film; A structure comprising a gate insulating film may be formed, and then the release layer may be removed and peeled off. After transferring to a flexible substrate, the remaining structure may be formed to produce a film display device. . In addition, a base insulating film on a separation layer provided over the substrate before the separation treatment, a semiconductor film including a channel region and a source or drain region formed on the base insulating film, a gate insulating film, A structure comprising a gate electrode formed over the channel region of the semiconductor film via a gate insulating film and an interlayer insulating film formed so as to cover the gate electrode is formed, and then the release layer is removed and the interlayer insulating film is removed. An opening reaching the source or drain region of the semiconductor film may be formed in the film, and the film may be peeled off and transferred to a flexible substrate, and then the remaining structure may be formed to manufacture a film display device.

  In the display device manufacturing method of the present invention, a separation layer is formed over a plurality of substrates, an element formation portion that forms part of the display device is formed over the separation layer, and an opening is formed in the element formation portion. Then, the release layer is exposed, an etching agent is introduced into the opening, the release layer is removed, a plurality of substrates each provided with an element formation portion are arranged, and an element formed on each of the plurality of substrates is formed. The first sheet material is bonded to the first sheet material, the element forming portion is peeled from the plurality of substrates, and the other surface of the element forming portion is bonded to the second sheet material. The element forming portion is peeled off, a pixel portion is formed in the element forming portion using a processing means, and one surface of the element forming portion is bonded to a third sheet material and sealed. In the above structure, the present invention can also be applied to a case where the structure of the element forming portions among the element forming portions formed on the plurality of substrates is different. In this case, one display device can be formed by combining structures of element formation portions having different functions.

  In the above configuration, the processing means is means for forming a pixel portion. The pixel portion includes any conductive layer such as a wiring or an electrode, an insulating film such as an interlayer insulating film or a protective film, a light emitting layer such as an EL element, or a pixel portion such as a liquid crystal. In addition, a conductive film such as a wiring connecting the driver circuit portion and the like provided in the periphery of the pixel region and the pixel portion, an insulating film covering the wiring, and the like can be formed by the processing means. As the processing means, a droplet discharge method, various printing methods such as a screen printing method and a gravure printing method, and an atmospheric pressure plasma apparatus can be used.

  By using the display device manufacturing apparatus of the present invention, a display device provided over a flexible substrate can be efficiently manufactured at low cost. In addition, by using the manufacturing method of the present invention, a display device including a thin film transistor with high characteristics can be obtained.

  Embodiments of the present invention will be described below with reference to the drawings. However, the present invention is not limited to the following description, and it is easily understood by those skilled in the art that modes and details can be variously changed without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the description of the embodiments below. Note that in the structures of the present invention described below, the same reference numerals are used in common in different drawings.

  In the present invention, at least a part of a display device is formed in advance on a substrate having rigidity such as glass, and then the substrate is peeled and provided on a flexible substrate, and then the remaining portion of the display device is formed. Thus, a display device is manufactured. The schematic diagram is shown in FIG. 1A illustrates a manufacturing process of a display device, and FIG. 1B illustrates a schematic diagram of a display device in each process.

  As shown in FIG. 1A, a display device manufacturing apparatus proposed by the present invention transports a substrate 101 provided with an element formation portion 102 (hereinafter referred to as an element formation portion 102) constituting the display device. Means 100, a first sheet material 103 having an adhesive layer on at least one surface, and a second sheet material 104 and a third sheet material 106 for sealing the display device. Further, a control unit 111 that controls the position of the substrate 101, a first peeling unit 112 that peels the element forming unit 102 from the substrate 101, and a second peeling unit 113 that peels the element forming unit 102 from the first sheet material 103. The element forming portion 102 is provided with a processing means 114 for forming one or both of a conductive film and an insulating film, a sealing means 115 for sealing the element forming portion 102, and the like. Note that all these configurations may be provided, or some configurations may be combined.

  In the apparatus shown in FIG. 1, first, the substrate 101 provided with the element formation portion 102 is transported by the transport means 100. At this time, the position of the substrate is adjusted by the control means 111. In addition, when one display device is formed by connecting element formation portions formed respectively on a plurality of substrates, the position of the plurality of substrates is adjusted by the control unit 111. In this case, the substrates may be bonded together.

  As the control unit 111 (used for adjusting the position of the substrate), a CCD (charge coupled device) camera or the like can be used. By arranging a plurality of substrates with high precision, a large display device can be manufactured by connecting element forming portions constituting a display device provided on the plurality of substrates. Note that in the case where a display device is formed by connecting a plurality of substrates, it is necessary to make the boundary between the connected portions inconspicuous when performing display on the pixel portion. In the present invention, it is possible to prevent the boundary from being noticeable by forming the gap between the pixels at the boundary, or by forming the wiring, the electrode, the light emitting layer, the liquid crystal, or the like after the connection. It becomes.

  Subsequently, the element forming portion 102 provided on the substrate 101 is bonded to the first sheet material 103 by the first peeling means 112 and peeled from the substrate 101. Then, the peeled element forming portion 102 flows to the next process while being adhered to the first sheet material. At the same time, the substrate 101 is recovered and reused.

  Next, the element forming portion 102 which is a thin film bonded to the first sheet material 103 is bonded to the second sheet material 104 by the second peeling means 113 and peeled off from the first sheet material 103. Then, the element forming portion 102 is bonded to the second sheet material 104 and flows to the next process.

  Next, wiring, a light emitting layer, an electrode, and the like are formed by the processing means 114 on the surface of the element forming portion 102 bonded to the second sheet material 104. As the processing unit 114, it is preferable to use a unit that can be directly formed on the element forming portion 102. For example, various printing methods such as a droplet discharge method, screen printing, and gravure printing can be used. By directly forming a wiring, a light emitting layer, an electrode, and the like in the element formation portion 102 by using a droplet discharge method or a printing method, it is possible to improve material utilization efficiency and work efficiency.

  Subsequently, the third sheet material 106 is adhered to the surface of the element forming unit 105 processed by the processing unit 114 by the sealing unit 115, and the element forming unit 105 is bonded to the second sheet material 104 and the third sheet. Sealed with a material 106.

  Through the above process, a display device can be manufactured. Note that a film-like display device can be manufactured by using a flexible film-like sheet material for the second sheet material and the third sheet material. The manufacturing method and the manufacturing apparatus of the display device of the present invention can be used for any display device including a liquid crystal display device and a display device using a light emitting element. Further, the present invention can be applied to either an active matrix display device or a passive matrix display device.

  Hereinafter, a more specific configuration of the present invention will be described with reference to the drawings.

(Embodiment 1)
In the first embodiment, a more specific configuration of the display device manufacturing apparatus shown in FIG. 1 will be described with reference to the drawings.

  As shown in FIG. 2, the apparatus shown in the first embodiment is a transfer means 10 for transferring a substrate 11 provided with an element forming portion 12 (hereinafter referred to as an element forming portion 12) that constitutes a part of the display device. And the control means 21 for adjusting the position of the substrate 11, the first supply roll 14 around which the first sheet material 13 is wound, and the element forming portion 12 from the substrate 11 are bonded to the first sheet material 13. The first peeling means 22 having the roller 26 to peel off, the second supply roll 17 around which the second sheet material 16 is wound, and the element forming unit 12 from the first sheet material 13 to the second The second peeling means 23 provided with rollers 27 and 28 that are adhered and peeled to the sheet material 16, the collecting roll 15 for collecting the first sheet material 13, and the process for forming the pixel portion in the element forming portion 12 Means 24 and third sheet material 18 Third supply roll 19 to be supplied, sealing means 25 for sealing the element forming portion processed by the processing means with the second sheet material 16 and the third sheet material 18, and sealed element formation And a collecting roll 20 that winds up the portion 12. The overall flow will be described below.

  First, the element forming unit 12 provided on the substrate 11 is transported by the transport means 10. The position of the substrate is adjusted by the control means 21 in the element forming portion 12 that has been transported. Then, it flows in the direction of the roller 26. If the accuracy of the substrate position is not so strict, the position control means 21 may not be provided. When a display device is formed by connecting element formation portions formed on a plurality of substrates, the positions are adjusted by the control means 21 and the substrates are bonded to each other.

  Next, the first sheet material 13 supplied from the first supply roll 14 is bonded to the element forming portion 12 provided on the substrate 11 by the first peeling means 22 provided with the roller 26, and the substrate 11, the element forming portion 12 is peeled off. Thereafter, the peeled element forming portion 12 is bonded to the first sheet material 13 and flows in the direction of the roller 27. Further, the second sheet material 16 supplied from the second supply roll 17 flows in the direction of the roller 28.

  Then, the second sheet material 16 is adhered to the surface of the element forming portion 12 that has been adhered and transported to the first sheet material 13 by the second peeling means 23 provided with the rollers 27 and 28, and the first sheet material 13 is transported. The element forming portion 12 is peeled from the sheet material 13. Note that the second peeling means 23 performs one or both of the pressure treatment and the heat treatment when the element forming portion 12 bonded to the first sheet material 13 is bonded to the second sheet material 16. Thereafter, the peeled element forming portion 12 is bonded to the second sheet material 16 and flows in the direction of the processing means 24.

  In the processing means 24, a pixel portion is formed in the element forming portion 12 that has flowed from the second peeling means 23. Any processing means may be formed as long as it constitutes a light emitting layer such as a conductive film, an insulating film, an organic EL element, or a pixel portion such as a liquid crystal. The processing means 24 includes a droplet discharge method in which a composition including a conductor, an insulator, a semiconductor, or the like is discharged (jetted) to directly form a pattern, a printing method such as screen printing or gravure printing, an atmospheric pressure plasma apparatus Etc. can be used. Thereafter, the element forming portion in which the pixel portion is formed flows in the direction of the sealing unit 25. Further, the third sheet material 18 supplied from the third supply roll 19 flows in the direction of the roller 30.

  In the sealing means 25, the surface of the element forming portion that has been transported while being bonded to the second sheet material is bonded to the third sheet material 18, and one or both of the pressure treatment and the heat treatment are performed. Do. After that, the sandwiched (sealed) element forming portion flows in the direction of the recovery roll 20 and winds around the recovery roll 20.

  As described above, in the apparatus shown in FIG. 2, the first sheet material 13 is supplied from the first supply roll 14 and flows in the order of the roller 26 and the roller 27 included in the first peeling unit 22. It is collected on the collection roll 15. The first supply roll 14, the roller 26, and the roller 27 rotate in the same direction. The second sheet material 16 is supplied from the second supply roll 17, flows in the order of the roller 28 included in the second peeling means 23, and the roller 29 included in the sealing means 25, and is recovered in the recovery roll 20. The second supply roll 17, the roller 28, and the roller 29 rotate in the same direction. The third sheet material 18 is supplied from the third supply roll 19 and is collected by the collection roll 20 after flowing through the roller 30 included in the sealing means 25. The third supply roll 19 and the roller 30 rotate in the same direction.

  The transport means 10 transports the substrate 11 on which the element forming unit 12 is provided. In FIG. 2, the transport unit 10 includes a roller 31, and the substrate 11 is transported by the rotation of the roller 31. The transport means 10 may have any configuration as long as the substrate 11 can be transported. For example, a belt conveyor, a plurality of rollers, a robot arm, or the like can be used. The robot arm transports the substrate 11 as it is, or transports the stage on which the substrate 11 is provided. Further, the transport unit 10 transports the substrate 11 at a predetermined speed in accordance with the speed at which the first sheet material 13 moves.

  A first sheet material 13, a second sheet material 16, and a third sheet material 18 are wound around the first supply roll 14, the second supply roll 17, and the third supply roll 19, respectively. ing. By rotating the first supply roll 14 at a predetermined speed, the first sheet material 13 is caused to flow toward the roller 27 included in the second peeling means at a predetermined speed, and the second supply roll 17 and By rotating the third supply roll 19 at a predetermined speed, the second sheet material 16 and the third sheet material 18 are caused to flow at a predetermined speed toward the sealing means 25. The first supply roll 14, the second supply roll 17, and the third supply roll 19 are cylindrical and are made of a resin material, a metal material, a rubber material, or the like.

  The 1st sheet | seat material 13 consists of a flexible film, and the surface which has an adhesive is provided in the at least one surface. Specifically, an adhesive is provided on a base film used as a base material such as polyester. As the adhesive, a material made of a resin material containing an acrylic resin or the like or a synthetic rubber material can be used. The first sheet material 13 is preferably a film having a low adhesive strength (adhesive strength is preferably 0.01 N to 1.0 N, more preferably 0.05 N to 0.5 N). This is because, after the element forming portion provided on the substrate is bonded to the first sheet material, the second sheet material is bonded to the element forming portion, and the first sheet material is peeled off from the element forming portion. It is. This is to make it happen. The thickness of the adhesive can be 1 μm to 100 μm, preferably 1 μm to 30 μm. Moreover, as a base film, since it becomes easy to handle at the time of processing, it is preferable if it forms in 10 micrometers-1 mm using films, such as polyester.

  When the surface of the adhesive layer is protected by the separator 32, a separator collection roll 33 is provided as shown in FIG. 2 when used, and the separator 32 may be removed during use. In addition, a base film used as a base material that has been subjected to antistatic treatment can also be used. The separator is made of a film such as polyester or paper, but is preferably formed of a film such as polyethylene terephthalate because paper dust or the like is not generated during processing.

  The second sheet material 16 and the third sheet material 18 are made of a flexible film, and for example, a laminate film or paper made of a fibrous material can be used. Laminated film refers to all films that can be used for sealing such as laminating treatment, and is made of materials such as polypropylene, polystyrene, polyester, vinyl, polyvinyl fluoride, vinyl chloride, methyl methacrylate, nylon, polycarbonate, etc. Processing such as embossing may be applied to the surface.

  Moreover, in this Embodiment, it is preferable to seal an element formation part using a hot-melt-adhesive. A hot-melt adhesive is a chemical substance that does not contain water or a solvent, is made of a solid and non-volatile thermoplastic material at room temperature, and adheres to an object by being applied and cooled in a molten state. In addition, the bonding time is short, pollution-free, safe and hygienic, energy saving, and low cost.

  Since the hot-melt adhesive is solid at room temperature, it can be used in the form of a film or fiber, or a film obtained by forming an adhesive layer in advance on a base film such as polyester. Here, a sheet material in which a hot melt film is formed on a base film made of polyethylene terephthalate is used. The hot melt film is made of a resin having a softening point lower than that of the base film. When heated, only the hot melt film is melted to form a rubber-like adhesive and is cured when cooled. Further, as the hot melt film, for example, a film mainly composed of ethylene / vinyl acetate copolymer (EVA), polyester, polyamide, thermoplastic elastomer, polyolefin or the like can be used.

  One or both of the second sheet material 16 and the third sheet material 18 may have an adhesive surface on one surface. As the adhesive surface, a material to which an adhesive such as a thermosetting resin, an ultraviolet curable resin, an epoxy resin adhesive, a photocurable adhesive, a moisture curable adhesive, or a resin additive is applied can be used.

  In addition, one or both of the second sheet material 16 and the third sheet material 18 may have translucency. In addition, one or both of the second sheet material 16 and the third sheet material 18 has a conductive film such as a thin film (diamond-like carbon film) mainly composed of carbon as a protective film or indium tin oxide (ITO). It may be coated with a material. In addition, as the second sheet material 16 and the third sheet material 18, a film (hereinafter referred to as an antistatic film) on which an antistatic measure for preventing static electricity or the like is applied can be used. Examples of the antistatic film include a film in which an antistatic material is dispersed in a resin, a film on which an antistatic material is attached, and the like. The film provided with an antistatic material may be a film provided with an antistatic material on one side, or a film provided with an antistatic material on both sides. Furthermore, a film provided with an antistatic material on one side may be attached to the layer so that the surface provided with the antistatic material is on the inside of the film, or on the outside of the film. It may be pasted. Note that the antistatic material may be provided on the entire surface or a part of the film. As the antistatic material here, a surfactant such as metal, indium and tin oxide (ITO), an amphoteric surfactant, a cationic surfactant or a nonionic surfactant is used. it can. In addition, as the antistatic material, a resin material containing a crosslinkable copolymer polymer having a carboxyl group and a quaternary ammonium base in the side chain can be used. An antistatic film can be obtained by sticking, kneading, or applying these materials to a film. By sealing with an antistatic film, it is possible to suppress adverse effects on the element forming portion due to external static electricity or the like when handled as a product.

  The control means 21 controls the position of the substrate 11 being conveyed. In FIG. 2, the substrate 11 is arranged by using a CCD camera. In addition, a display device in which a plurality of substrates are connected to each other can be manufactured by accurately controlling and arranging the positions of the plurality of substrates. At this time, the control means 21 accurately controls the positions of the plurality of substrates to bond the substrates together. Note that in the case where a joined boundary is formed in the pixel portion, it is necessary to make the boundary inconspicuous. In the present embodiment, the control means 21 can accurately connect and connect a plurality of substrates, and the processing means 24 can form wirings, electrodes, or light-emitting layers after the connection, thereby making the boundary more inconspicuous. It becomes possible. In addition, when it is not necessary to arrange a board | substrate correctly, the control means 21 does not need to be provided.

  The first peeling means 22 includes at least a roller 26 and peels the element forming portion 12 from the substrate 11 by bonding one surface of the element forming portion 12 to one surface of the first sheet material 13. As the roller 26 rotates, the element forming unit 12 adheres to the first sheet material 13, and the element forming unit 12 is peeled from the substrate 11. Therefore, the roller 26 is provided so as to face the substrate 11 on the side where the element forming portion 12 is provided. The roller 26 has a cylindrical shape, and is made of a resin material, a metal material, a rubber material, or the like, preferably a soft material.

  The second peeling means 23 includes at least rollers 27 and 28 facing each other, and adheres the element forming portion 12 adhered to the first sheet material 13 to one surface of the second sheet material 16 to thereby The element forming portion 12 is peeled from the sheet material 13. At this time, the element forming portion is adhered to the second sheet material 16 flowing from the second supply roll 17 toward the roller 28, and when passing between the roller 27 and the roller 28, the roller 27 and the roller One or both of 28 are used to perform one or both of the pressure treatment and the heat treatment.

  By performing this process, the element forming portion 12 bonded to the first sheet material 13 is bonded to the second sheet material 16. Any method can be used for the heat treatment as long as heat energy can be applied. For example, oven, heating wire heater, temperature medium such as oil, hot stamp, thermal head, laser beam, infrared flash, thermal pen, etc. Can be appropriately selected and used. The rollers 27 and 28 are cylindrical and are made of a resin material, a metal material, a rubber material, or the like, preferably a soft material.

  The processing means 24 forms a pixel portion on the surface of the element forming portion 12 adhered to the second sheet material 16. Specifically, a conductive film such as a wiring or an electrode, an insulating film, a light emitting layer, a liquid crystal, or the like necessary for completing a pixel of a display device is formed. As processing means, a droplet discharge method for directly forming a pattern by discharging (jetting) a composition containing a conductor or an insulator, or a screen printing or gravure printing method for transferring a pattern by placing a material on an original plate Or the like can be used. In this embodiment mode, a case where a droplet discharge method is used is shown. For example, when a semiconductor film, a gate electrode, a wiring, a pixel electrode, and the like are formed on the substrate 11 in advance, a light emitting layer, a counter electrode, and the like are formed by selectively discharging droplets using the processing unit 24. Alternatively, only the semiconductor layer may be formed on the substrate 11, and then the gate electrode, the wiring, the pixel electrode, the light emitting layer, the counter electrode, or the like may be formed by using the processing means 24. It can be carried out.

  Further, in the present embodiment, since the element forming portion 12 peeled from the substrate 11 by the first peeling means 22 is further peeled by the second peeling means, the element forming portion flowing into the processing means 24 is removed. The surface is the same as the surface of the element forming portion formed on the substrate 11. In this way, by performing the peeling twice, the processing means 24 can efficiently carry out the formation of the light emitting layer or the like in the element forming portion.

  When the element forming portion processed by the processing means 24 flows, the sealing means 25 adheres the third sheet material 18 to the surface of the element forming portion, and the element forming portion becomes the second sheet material 16. And the third sheet material 18. Further, the sealing means 25 includes a roller 29 and a roller 30 provided to face each other. The third sheet material 18 that flows from the third supply roll 19 toward the roller 30 is adhered to the other surface of the element forming portion, and when passing between the roller 29 and the roller 30, the roller 29 And the roller 30 are used to perform one or both of pressure treatment and heat treatment. By performing this process, the element forming portion is sealed with the second sheet material 16 and the third sheet material 18.

  One or both of the rollers 29 and 30 constituting the sealing means 25 have a heating means. As the heating means, for example, an oven, a heating wire heater, a heating medium such as oil, a hot stamp, a thermal head, a laser beam, an infrared flash, a thermal pen, or the like can be used. Further, the roller 29 and the roller 30 rotate at a predetermined speed in accordance with the rotation speed of the roller 28, the second supply roll 17, and the third supply roll 19. The rollers 29 and 30 are cylindrical and are made of a resin material, a metal material, a rubber material, or the like, preferably a soft material.

  The collection roll 20 is a roll that collects by winding up the element forming portion sealed by the second sheet material 16 and the third sheet material 18. The collection roll 20 rotates at a predetermined speed in accordance with the rotation speed of the roller 29 and the roller 30. The collection roll 20 has a cylindrical shape, and is made of a resin material, a metal material, a rubber material, or the like, preferably a soft material.

  Thus, according to the apparatus shown in FIG. 2, the first to third supply rolls 14, 15, 21, the rollers 26, 31, 27, 28, 29, 30 and the collection roll 20 are rotated. The element forming portion 12 provided on the substrate 11 can be continuously peeled, sealed and collected. Therefore, the apparatus shown in FIG. 2 is high in mass productivity and can improve manufacturing efficiency.

  Next, the form of the manufacturing apparatus of the film-like display apparatus different from the above will be described with reference to FIG.

  The apparatus shown in FIG. 3 includes a transport unit 10 that transports the substrate 11 provided with the element forming unit 12, a control unit 21 that adjusts the position of the substrate 11, and a first sheet member 13 around which the first sheet material 13 is wound. A first roll 22 having a roll 14 for supply, a first peeling means 22 having a roller 26 for peeling the element forming portion 12 from the substrate 11 to the first sheet material 13, and a second sheet material 16 wound around. 2 supply rolls 17, second peeling means 23 for bonding the element forming portion 12 to the second sheet material 16 from the first sheet material 13, and recovery for collecting the first sheet material 13. The resin 55 is extruded in a heated and melted state to the surface of the element forming portion 12 opposite to the surface to which the second roll material 16 is bonded, the processing means 24 for forming the pixel portion in the element forming portion 12, and the surface to which the second sheet material 16 is bonded. , Second sheet material 16 and resin 55 Ri has a sealing means 25 for sealing the element forming portion, and a recovery roll 20 for winding up the sealed element forming portion 12. The configuration shown in FIG. 3 is a configuration in which the third supply roll 19 and the third sheet material 18 are replaced with a die 54 and a resin 55 in the configuration shown in FIG.

  In the apparatus shown in FIG. 3, the element forming portion 12 provided on the substrate 11 is peeled off by the first sheet material 13, and the element forming portion 12 bonded to the first sheet material is bonded to the second sheet material 16. The process until the element forming portion 12 bonded to the second sheet material 16 is processed by the processing means 24 and flows toward the sealing means 25 can be performed in the same manner as in FIG. Thereafter, in FIG. 3, the resin extruded from the die 54 to the other surface (the surface opposite to the surface to which the second sheet material is bonded) of the element forming portion bonded to the second sheet material 16 in a heated and melted state. 55 is supplied. Subsequently, the second sheet material 16 and the resin 55 introduced between the pressure roller 56 and the cooling roller 57 are cooled while being pressed by the pressure roller 56 and the cooling roller 57, so that the other of the element forming portions is cooled. The resin 55 is adhered to the surface, and the element forming portion 12 is sealed with the second sheet material 16 and the resin 55. Finally, the sealed element forming portion 12 flows in the direction of the collection roll 20 and is wound around the collection roll 20 and collected.

  In the configuration of the laminating apparatus illustrated in FIG. 3, a thermoplastic resin may be used as the resin 55. The thermoplastic resin used for the resin 55 preferably has a low softening point. For example, polyolefin resins such as polyethylene, polypropylene and polymethylpentene, vinyl resins such as vinyl chloride, vinyl acetate, vinyl chloride-vinyl acetate copolymer, ethylene-vinyl acetate copolymer, vinylidene chloride, polyvinyl butyral, polyvinyl alcohol, etc. Copolymers, acrylic resins, polyester resins, urethane resins, cellulose, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cellulose resins such as ethyl cellulose, styrene such as polystyrene and acrylonitrile-styrene copolymers Based resins and the like. The resin 55 may be extruded from a single layer from the die 54 or may be extruded from two or more layers. The first sheet material 13 or the second sheet material 16 can use any of the materials described above.

  Thus, according to the apparatus shown in FIG. 3, the conveying means 10, the first and second supply rolls 14 and 17, the roller 26, the rollers 27 and 28, the pressure roller 56, the cooling roller 57, and the recovery roll 20. Is rotated, the element forming portion 12 provided on the substrate 11 can be continuously peeled, sealed and collected. Therefore, the apparatus shown in FIG. 3 has high mass productivity and can improve manufacturing efficiency.

  Next, the form of the manufacturing apparatus of a film-like display apparatus different from the above will be described with reference to FIG.

  The cassette 41 is a cassette for supplying a substrate, on which the substrate 11 provided with a plurality of element forming portions 12 is set. The cassette 42 is a cassette for collecting a substrate, and the substrate 11 after the element forming unit 12 is peeled is collected. A plurality of rollers 43 to 45 are provided between the cassette 41 and the cassette 42 as a conveying means, and the substrate 11 is conveyed by the rotation of the rollers 43 to 45.

Thereafter, as described above, the element forming portion 12 is peeled off and sealed, and then the sealed element forming portion 12 is cut by the cutting means 46. The cutting means 46 uses a dicing apparatus, a scribing apparatus, a laser irradiation apparatus (such as a CO ₂ laser irradiation apparatus) or the like. Through the above steps, the sealed element forming portion 12 is completed.

  In the present embodiment, the peeled substrate 11 can be reused. Therefore, cost reduction can be achieved even when a quartz substrate having a higher cost than a glass substrate is used. In the case where a quartz substrate is used, a condition of a manufacturing process associated with the substrate is relaxed as compared with that of a glass substrate, so that a display device with higher characteristics can be formed. Note that when the substrate is reused, it is desirable to control the substrate so that scratches are not generated in the peeling process. However, even when scratches are generated, planarization may be performed by forming an organic resin or inorganic resin film by a coating method or a droplet discharge method, or by grinding or polishing.

  As described above, by using the device described in this embodiment, a flexible display device can be manufactured efficiently.

(Embodiment 2)
Next, a specific example of a method for manufacturing a display device will be described with reference to drawings.

  In this embodiment mode, a part of a display device is formed in advance on a heat-resistant substrate such as glass, and then the part of the display device formed on the substrate is peeled off to be on a flexible substrate. A case of providing and forming the remaining part of the display device will be described.

  In general, as shown in FIG. 5A, a schematic diagram of a display device includes a pixel region 402 including a plurality of pixel portions on a substrate 200 such as a glass substrate, and a driving circuit 403 for driving the pixel portions. 404 is provided. In addition, a circuit for controlling the pixel portion is provided on the substrate 200 or electrically connected to the outside.

  In this embodiment, instead of completing the display device over the substrate 200, after forming a part of the structure of the display device over the substrate 200, the part of the structure of the display device once formed is flexible. Is provided on the substrate. Subsequently, a portion constituting the remaining display device is formed again. A specific manufacturing process will be described below with reference to FIGS.

  First, as shown in FIG. 6A, a separation layer 201, a first insulating film 202, a second insulating film 203, a semiconductor film 204, a gate insulating film 205, a gate electrode 206, an interlayer insulating film are formed over a substrate 200. 207, source or drain electrodes 208 and 209, a pixel electrode 210, a wiring 211, and a partition wall 212 are provided. Note that the cross-sectional view illustrated in FIG. 6 corresponds to a cross section taken along a line AB in FIG. Hereinafter, the structure in FIG. 6A will be described in detail.

  As the substrate 200, for example, a glass substrate such as barium borosilicate glass or alumino borosilicate glass, a quartz substrate, a ceramic substrate, or the like can be used. Alternatively, a metal substrate containing stainless steel or a semiconductor substrate with an insulating film formed on the surface thereof may be used. The surface of the substrate 200 may be planarized by polishing such as a CMP method.

The separation layer 201 provided over the substrate 200 is formed using a metal film containing tungsten (W), molybdenum (Mo), niobium (Nb), titanium (Ti), or the like, or a semiconductor film such as silicon (Si). In this embodiment, a metal film containing W is used as the separation layer 201. Note that a method for forming W can be formed by a CVD method, a sputtering method, an electron beam, or the like. Here, the W is formed by a sputtering method. Alternatively, a film in which a metal oxide (for example, WO _x ) is formed over a metal film (for example, W) may be used as the release layer 201. In addition, as a combination of a metal film and a metal oxide film, Mo and MoOx, Nb and NbOx, Ti and TiOx (X = 2 to 3), or the like can be used.

  In FIG. 6, the peeling layer 201 is formed directly on the substrate 200, but a base film may be formed between the substrate 200 and the peeling layer 201. The base film is a single insulating film containing oxygen or nitrogen, such as silicon oxide (SiOx), silicon nitride (SiNx), silicon oxynitride (SiOxNy) (x> y), silicon nitride oxide (SiNxOy) (x> y), or the like. A layer structure or a stacked structure thereof can be used. In particular, when there is a concern about contamination from the substrate, it is preferable to form a base film between the substrate 200 and the peeling layer 201.

  After the separation layer 201 is formed over the substrate 200, an insulating film is formed over the separation layer 201. The insulating film can be formed with a single-layer structure or a stacked structure. In FIG. 6, the insulating film is formed with a stacked structure including the first insulating film 202 and the second insulating film 203. As the insulating film, for example, a silicon oxide film is used as the first insulating film 202, and a silicon oxynitride film is used as the second insulating film 203. In addition, a three-layer structure including a silicon oxide film as the first insulating film, a silicon nitride oxide film as the second insulating film, and a silicon oxynitride film as the third insulating film may be formed.

  Next, a thin film transistor is formed over the second insulating film 203. The thin film transistor includes a semiconductor film 204 patterned into at least a desired shape, a gate electrode 206 formed through a gate insulating film 205, an interlayer insulating film 207, and source or drain electrodes 208 and 209 electrically connected to the semiconductor film 204. It is composed of

  The semiconductor film 204 includes an amorphous semiconductor, a SAS in which an amorphous state and a crystalline state are mixed, a microcrystalline semiconductor in which a crystal grain of 0.5 nm to 20 nm can be observed in the amorphous semiconductor, and crystallinity. It may have any state selected from semiconductors. If a substrate that can withstand the film formation temperature, for example, a quartz substrate is used, a crystalline semiconductor film may be formed on the substrate by a CVD method or the like.

  In this embodiment, an amorphous semiconductor film is formed and a crystalline semiconductor film crystallized by heat treatment is formed. The heat treatment can be performed using a heating furnace, laser irradiation, irradiation of light emitted from a lamp instead of laser light (lamp annealing), or a combination thereof.

  The gate insulating film 205 is formed so as to cover the semiconductor film 204. The gate insulating film 205 can be formed by stacking a single layer or a plurality of films using, for example, silicon oxide, silicon nitride, silicon nitride oxide, or the like. As a film formation method, a plasma CVD method, a sputtering method, or the like can be used.

  The gate electrode 206 is formed on the gate insulating film 205. The gate electrode 206 can be formed of, for example, an element selected from Ta, W, Ti, Mo, Al, Cu, Cr, and Nd, or an alloy material or a compound material containing the element as a main component. Alternatively, a semiconductor film typified by a polycrystalline silicon film doped with an impurity element such as phosphorus may be used. Further, an AgPdCu alloy may be used. Furthermore, the combination may be selected as appropriate. The gate electrode 206 may have a single-layer structure or a stacked structure including a plurality of layers.

  Next, an impurity imparting n-type or p-type conductivity is selectively added to the semiconductor film 204 using a gate electrode or a resist pattern formed and patterned as a mask. The semiconductor film 204 includes a channel formation region and an impurity region (including a source region, a drain region, a GOLD region, and an LDD region), and an n-channel TFT or a p-channel TFT is formed depending on the conductivity type of the added impurity element. It can be formed selectively. Further, a sidewall may be formed on the sidewall of the gate electrode 206.

  Next, an interlayer insulating film 207 is formed. As the interlayer insulating film 207, an inorganic insulating film or an organic insulating film can be used. As the inorganic insulating film, a silicon oxide film, silicon oxynitride formed by a CVD method, a silicon oxide film applied by a SOG (Spin On Glass) method, or the like can be used. As an organic insulating film, polyimide, polyamide, or the like can be used. A film of BCB (benzocyclobutene), acrylic or positive photosensitive organic resin, negative photosensitive organic resin, or the like can be used. Alternatively, a stacked structure of an acrylic film and a silicon oxynitride film may be used.

  A siloxane resin can be used as the interlayer insulating film. A siloxane resin corresponds to a resin including a Si—O—Si bond. Siloxane has a skeleton structure formed of a bond of silicon (Si) and oxygen (O). As a substituent, an organic group containing at least hydrogen (for example, an alkyl group or an aromatic hydrocarbon) is used. A fluoro group may be used as a substituent. Alternatively, an organic group containing at least hydrogen and a fluoro group may be used as a substituent.

  Siloxane resins can be classified according to their structure into, for example, silica glass, alkylsiloxane polymers, alkylsilsesquioxane polymers, hydrogenated silsesquioxane polymers, hydrogenated alkylsilsesquioxane polymers, and the like. Alternatively, the interlayer insulating film may be formed using a material containing a polymer (polysilazane) having a Si—N bond.

  By using the above material, an interlayer insulating film having sufficient insulation and flatness can be obtained even when the film thickness is reduced. In addition, since the above material has high heat resistance, an interlayer insulating film that can withstand reflow processing in a multilayer wiring can be obtained. Further, since the hygroscopic property is low, an interlayer insulating film with a small amount of dehydration can be formed.

  Next, the interlayer insulating film 207 is etched to form contact holes reaching the source and drain regions of the semiconductor film 204. Subsequently, source or drain electrodes 208 and 209 and wirings 211 electrically connected to the source and drain regions are formed. The source or drain electrodes 208 and 209 and the wiring 211 are made of one element selected from Al, Ni, C, W, Mo, Ti, Pt, Cu, Ta, Au, and Mn or an alloy containing a plurality of such elements. A single layer or a stacked structure can be used. For example, a laminated film of a Ti film and an alloy film containing Al and Ti can be formed by patterning. Of course, not only a two-layer structure but also a single-layer structure or a laminated structure of three or more layers may be used.

  Next, the pixel electrode 210 is formed on the interlayer insulating film 207. The pixel electrode 210 is formed so as to be electrically connected to the source or drain electrode 208. In FIG. 6, the pixel electrode 210 is formed after the source or drain electrode 208 is formed; however, the source or drain electrode 208 may be formed after the pixel electrode 210 is formed first.

  When the pixel electrode 210 is used as an anode, it is preferable to use a material having a high work function. For example, in addition to single layer films such as ITO (indium tin oxide) film, IZO (indium zinc oxide) film, titanium nitride film, chromium film, tungsten film, Zn film, Pt film, titanium nitride film and aluminum A stack of a film containing a main component, a three-layer structure of a titanium nitride film, a film containing aluminum as a main component, and a titanium nitride film can be used. Note that with a stacked structure, resistance as a wiring is low, good ohmic contact can be obtained, and a function as an anode can be obtained.

On the other hand, when the pixel electrode 210 is used as a cathode, it is preferable to use a material having a low work function. For example, Al, Ag, Li, Ca, or an alloy thereof, MgAg, MgIn, Al—Li, CaF ₂ , or CaN can be used. Note that in the case where it is desired to transmit light to the pixel electrode 210, the pixel electrode 210 includes a thin metal film, a transparent conductive film (ITO (indium tin oxide), indium zinc oxide alloy (In ₂ O ₃ —ZnO), zinc oxide (ZnO), or the like) is preferably used.

  Next, an insulating film is selectively formed so as to cover the end portions of the source or drain electrodes 208 and 209, the wiring 211, and the pixel electrode 210, and a partition wall 212 (hereinafter also referred to as an insulating film 212) is provided. As the partition wall 212, an organic material such as acrylic or polyimide, a material such as silicon oxide, silicon oxynitride, or a siloxane resin can be used. Preferably, the light emitting layer formed so as to cover the pixel electrode 210 later is formed in a shape in which the radius of curvature continuously changes so that the light emitting layer does not break.

  Through the above steps, the structure illustrated in FIG. 6A can be formed.

  Next, an opening 213 through which an etching agent is introduced is selectively formed, avoiding the formation portion of the thin film transistor and the wiring (FIG. 6B). The opening 213 is formed so that the separation layer 201 is exposed by removing the insulating film 212, the interlayer insulating film 207, the gate insulating film 205, the first insulating film 202, and the second insulating film 203.

  Subsequently, an etchant is introduced into the opening 213 to remove the peeling layer 201. In this embodiment mode, the peeling layer 201 is chemically reacted with the peeling layer to remove the peeling layer 201. The peeling layer 201 may be completely removed, but here, the peeling layer 201 is not completely removed, and at least a part of the peeling layer located below the pixel electrode 210 is left (FIG. 6C). The amount of the release layer remaining can be controlled by setting the etching flow rate and the reaction time in consideration of the reaction between the release layer and the etching agent. By leaving the release layer 201, the element formation portion 215 (hereinafter referred to as the element formation portion 215) constituting the display device from the substrate 200 is prevented from being completely separated and separated even after the release layer 201 is removed. be able to.

As the etchant, a gas or liquid containing halogen fluoride (interhalogen compound) that easily reacts with the release layer can be used. For example, when a W film is used as the peeling layer 201, it is preferable to use chlorine trifluoride gas (ClF ₃ ) that reacts well with W. In addition, CF ₄ , SF ₆ , NF ₃ , F ₂ or the like may be used as the etching agent, and the practitioner may select as appropriate.

  The opening 213 can be formed by irradiating laser light. Further, after the opening is formed by irradiating laser light, the peeling layer can be peeled off without removing the peeling layer using an etching agent. This is because the release layer is partially removed by laser light irradiation.

  Next, the first sheet material 214 is bonded to the insulating film 212 from the opposite side of the substrate 200, and the element formation portion 215 provided on the substrate 200 is peeled from the substrate 200 through the peeling layer 201 (FIG. 6). (D)). The first sheet material 214 is made of a flexible film, and an adhesive is provided on at least a surface in contact with the element forming portion 215. For example, a film in which a pressure-sensitive adhesive containing an acrylic resin or the like is provided on a base film made of polyester or the like can be used.

  Next, the surface of the element forming portion 215 opposite to the surface to which the first sheet material 214 is bonded is bonded to the second sheet material 216, and the element forming portion 215 is peeled off from the first sheet material 214. (FIG. 7A).

  Subsequently, a light emitting layer 217 is selectively formed over the pixel electrode 210 (FIG. 7B). The light emitting layer 217 may be selectively formed using a droplet discharge method, or may be formed using a screen printing method or a gravure printing method. In this embodiment mode, the light-emitting layer 217 is selectively formed by using a droplet discharge method. In the case of forming a display device capable of color display, light emitting layers that emit three colors of R, G, and B are selectively formed. In this manner, by forming the light-emitting layer using a droplet discharge method or a printing method, wasteful materials can be reduced, so that cost can be reduced.

  In the case where there is a problem with strength or the like, an insulating film or the like may be formed in the opening 213 before the light emitting layer 217 is formed. Also in this case, the insulating film can be selectively formed using a droplet discharge method.

  In addition, the light emitted from the light emitting element is formed by forming the upper surface emission from which light is emitted to the substrate side, the lower surface emission from which light is emitted, and a pair of electrodes with a transparent material or a thickness capable of transmitting light. There are two-sided emission in which light is emitted on both the substrate side and the opposite side, and either may be applied. The light emitting layer 217 may be any of a single layer type, a stacked type, and a mixed type having no layer interface. Further, the light-emitting layer 217 may use any of a singlet material, a triplet material, or a combination of these materials. Further, an organic material including a low molecular material, a high molecular material, and a medium molecular material, an inorganic material typified by molybdenum oxide having excellent electron injecting property, or a composite material of an organic material and an inorganic material may be used.

  After that, the counter electrode 218 is formed (FIG. 7B). The counter electrode 218 can also be selectively formed by discharging a composition containing a conductor using a droplet discharge method. In addition, as the material of the counter electrode 218, any of the materials described as the material of the pixel electrode 210 can be used depending on whether it is used as an anode or a cathode. Further, the counter electrode 218 may be formed over the entire surface. In this case, it is preferable that the opening 213 is filled with an insulating film in advance so that the counter electrode is not cut off by the opening 213. As the insulating film, a resin material such as polyimide, polyamide, BCB (benzocyclobutene), acrylic, or phenol can be used.

  Subsequently, the third sheet material 220 is bonded to the surface of the element forming portion 215 opposite to the surface bonded to the second sheet material 216, and the element forming portion 215 is connected to the second sheet material 216. Sealing is performed with the third sheet material 220 (FIG. 7C). Then, the element forming portion 215 is sealed with the second sheet material 216 and the third sheet material 220. Note that in the case where there is a concern about the water resistance of the light emitting layer, a protective film 219 may be formed before sealing. The protective film 219 is formed so that the light emitting layer is not brought into contact with external air or moisture. Therefore, as the protective film 219, only a resin material such as an epoxy resin, an acrylic resin, a phenol resin, a novolac resin, an acrylic resin, a melamine resin, a urethane resin or a liquid repellent material or a hydrocarbon containing fluorine atoms is used. The resin etc. which were comprised by can be used. More specifically, a resin containing a monomer containing a fluorine atom in the molecule, or a resin containing a monomer composed entirely of carbon and hydrogen atoms can be given. In addition, organic materials such as benzocyclobutene, parylene, flare, permeable polyimide, compound materials made by polymerization of siloxane resins, compositions containing water-soluble homopolymers and water-soluble copolymers, etc. are used. be able to. In addition, you may form with an inorganic material.

  Moreover, the 2nd sheet material 216 and the 3rd sheet material 220 consist of a flexible film, for example, can be formed with a laminate film. Specifically, a hot melt film formed on a base film such as polyester can be used here. When the second sheet material 216 and the third sheet material 220 are bonded to the element formation portion 215, bonding can be performed in a short time by performing one or both of pressure treatment and heat treatment. Further, by providing a counter electrode on the surface of the third sheet material, the counter electrode can be formed together when the element forming portion 215 is sealed.

  Note that in this embodiment mode, the peeled substrate 200 can be reused. As a result, in manufacturing a display device using a substrate, the same substrate can be used repeatedly. Therefore, even when a quartz substrate having a higher cost than a glass substrate is used, cost reduction can be achieved. Note that when the substrate is reused, it is desirable to control the substrate so that scratches are not generated in the peeling process. However, even when scratches are generated, planarization may be performed by forming an organic resin or inorganic resin film by a coating method or a droplet discharge method, or by grinding or polishing.

  The film display device is completed through the above steps. Note that in this embodiment mode, an example of an organic EL display device using an electroluminescent layer is shown; however, the present invention is not limited to this, and the present invention can be similarly applied to a display device using a liquid crystal display device or another light emitting element. it can. FIG. 22 shows the case where the above process is applied to a liquid crystal display device. First, as described above, the element forming portion 230 constituting a part of the liquid crystal display device is formed on a rigid substrate, and then the first sheet material 214 is bonded to one surface of the element forming portion 230. The element formation part 230 is peeled from the substrate. Here, the alignment film 271 is formed so as to cover the pixel electrode when the element formation portion is formed over the substrate. Next, the second sheet material 216 is bonded to the other surface of the element formation portion 230, and the element formation portion 230 is separated from the first sheet material 214 (FIG. 22A). Thereafter, a liquid crystal layer and a counter electrode are formed on the element formation portion 230 by a processing means (FIG. 22B). Note that the liquid crystal layer may be formed by a known method, for example, a dropping injection method or the like. Subsequently, the third sheet material 220 is bonded to the liquid crystal layer 219 and the counter electrode 229 formed on the element formation portion 230 and sealed with the second sheet material 216 and the third sheet material 220. Thus, a liquid crystal display device can be formed (FIG. 22C). The liquid crystal display device is formed between the alignment films 271 and 272, and can be displayed by providing polarizing plates above and below the liquid crystal display device.

  In addition, since a film-like display device manufactured using this embodiment has an opening 213 formed between pixels, the completed film-like display device can be folded at low cost. In other words, the provision of the opening 213 has an advantage that the pressure applied to the pixel when bent is reduced. Note that the same effect can be obtained by filling the opening 213 with a material that is easily bent. As the material that easily bends, an organic material such as polyethylene, vinyl acetate, ethylene vinyl acetate, polystyrene, polyurethane, polypropylene, polyvinyl fluoride, vinyl chloride, polyester, polyamide, or polyimide can be used.

  Note that in this embodiment mode, a top gate thin film transistor is described using a specific example; however, a bottom gate thin film transistor may be used. Further, although an example has been shown regarding the active matrix type, a passive matrix type configuration may be used. Although the pixel region has been described, a driver circuit for driving the pixel portion may be formed over the substrate in the same manner, and may be peeled off at the same time as the pixel region and provided over the flexible substrate. Wiring for connecting the pixel region and the driver circuit may be formed before peeling, or may be formed using a processing means after being provided on the flexible substrate after peeling. In addition, a driver circuit, a circuit for controlling a pixel region, and the like may be formed over another substrate, separated from the substrate, provided on the flexible substrate, and then a wiring for electrically connecting them may be formed. . In this case, since each structure can be made for each substrate, a display device can be formed efficiently.

  Note that this embodiment mode can be freely combined with the above embodiment modes.

(Embodiment 3)
In this embodiment, a mode different from the method for manufacturing the display device described in Embodiment 2 will be described with reference to drawings. Specifically, two kinds of manufacturing methods different from those in Embodiment Mode 2 will be described with reference to FIGS. Note that parts that are the same as those shown in the above embodiment are denoted by the same reference numerals.

  In the example shown in FIGS. 8 and 9, first, a display device including a separation layer 201, a first insulating film 202, a second insulating film 203, a semiconductor film 204, a gate insulating film 205, and the like is formed over a substrate 200. A part is provided and peeling from the substrate 200 is performed. After that, the peeled portion is transferred to a flexible substrate, and the remaining portions constituting the display device such as a gate electrode, an interlayer insulating film, a source or drain electrode, a wiring, a pixel electrode, a light emitting layer, and a counter electrode are formed. A specific manufacturing method will be described below. Note that unless otherwise specified in this embodiment, the same materials as those described in Embodiment 2 are used.

  First, a separation layer 201, a first insulating film 202, a second insulating film 203, a semiconductor film 204, and a gate insulating film 205 are formed over a substrate 200, and then an opening 231 for introducing an etchant is formed ( FIG. 8 (A)). The opening 231 is formed between a pixel portion and a pixel portion to be formed later, avoiding a semiconductor film and wiring and electrodes formed later.

  Subsequently, the peeling layer 201 is removed by introducing an etching agent. The separation layer 201 may be completely removed, but here, the separation layer 201 is completely removed so that an element formation portion 232 (hereinafter referred to as an element formation portion 232) constituting the display device is not peeled off from the substrate 200. Is not removed and a part is left (FIG. 8B).

  Next, the first sheet material 214 is adhered to the gate insulating film 205 on the surface of the element formation portion 232, and the element formation portion 232 connected to the substrate 200 via a part of the peeling layer is removed from the substrate 200. Peel off (FIG. 8C).

  Subsequently, the second sheet material 216 is bonded to the surface of the element forming portion 232 opposite to the surface to which the first sheet material 214 is bonded, and the element forming portion 232 that is a thin film is bonded to the first sheet material. It peels from 214 (FIG. 8D). In this manner, the substrate 200 can be replaced with a flexible substrate by performing peeling twice. Of the two peelings, the first sheet material used for the first peeling is preferably peeled off after adhering to the element forming portion 232, so that the first sheet material is weak.

  After that, the gate electrode 233, the interlayer insulating film 234, the source or drain electrodes 235 and 236, the wiring 237, the pixel electrode 238, the light emitting layer 217, and the counter electrode 218 are formed on the element formation portion 232 provided over the second sheet material 216. Are formed (FIGS. 9A to 9D).

  In FIG. 9A, the gate electrode 233 is selectively formed by a droplet discharge method. As the gate electrode, a conductive material having one or more metals such as Ag, Au, Cu, and Pd and a metal compound is used. Note that a conductive material having one or more metals, such as Cr, Mo, Ti, Ta, W, and Al, or a metal compound, can be used as long as aggregation can be suppressed by a dispersant. is there. Further, a gate electrode in which a plurality of conductive films are stacked can be formed by discharging a conductive material a plurality of times by a droplet discharge method. However, it is preferable to use a composition in which any one of Au, Ag, and Cu is dissolved or dispersed in a solvent in consideration of the specific resistance value, and more preferably the composition for discharging nozzle holes. Resistive Ag and Cu may be used. However, when Ag or Cu is used, a barrier film may be provided as a countermeasure against impurities. As the barrier film, a silicon nitride film or nickel boron (NiB) can be used.

  Next, an interlayer insulating film 234 is formed so as to cover the gate electrode 233 (FIG. 9B). Here, an interlayer insulating film 234 is selectively formed by discharging a solution obtained by dissolving or dispersing an insulator in a solvent by a droplet discharge method. Then, the gate insulating film 205 is etched by using the selectively formed interlayer insulating film 234 as a mask to form a contact hole reaching the source or drain region formed in the semiconductor film 204.

  As the insulator to be discharged, a resin material such as an epoxy resin, an acrylic resin, a phenol resin, a novolac resin, an acrylic resin, a melamine resin, or a urethane resin can be used. In addition, when using these resin materials, the viscosity is good to adjust by melt | dissolving or disperse | distributing using a solvent. Further, as the liquid repellent material, a resin containing a fluorine atom, a resin composed only of hydrocarbon, or the like can be used. More specifically, a resin containing a monomer containing a fluorine atom in the molecule, or a resin containing a monomer composed entirely of carbon and hydrogen atoms can be given. In addition, organic materials such as benzocyclobutene, parylene, flare, permeable polyimide, compound materials made by polymerization of siloxane resins, compositions containing water-soluble homopolymers and water-soluble copolymers, etc. are used. be able to. When an organic material is used, the flatness thereof is excellent, and therefore, even when a conductor is formed later, the film thickness is not extremely reduced at the stepped portion, and disconnection does not occur. . However, the organic material may be formed as a thin film of an inorganic material containing silicon in the lower layer and the upper layer in order to prevent outgassing.

  Next, source or drain electrodes 235 and 346, a wiring 237, and a pixel electrode 238 that are electrically connected to the source or drain region of the semiconductor film 204 are formed (FIG. 9C). Here, these electrodes or wirings are selectively formed by a droplet discharge method. The source or drain electrodes 235 and 236 and the wiring 237 can be formed using any of the materials shown for the gate electrode 233.

  After that, an insulating film 239 functioning as a partition wall (bank) is formed, a light emitting layer 217 and a counter electrode 218 are formed (FIG. 9D), and then the second sheet material as shown in FIG. 7C. And sealing with a third sheet material. The insulating film 239 can also be selectively formed by using a droplet discharge method. As the material for the insulating film 239, any of the materials described for the insulating film 234 can be used. The counter electrode 218 may be formed on the entire surface.

  In this manner, by forming an electrode, a wiring, or an insulating film by using a droplet discharge method, it is possible to improve the utilization efficiency of the material and to manufacture at a low cost. Here, the gate electrode, the insulating film, the wiring, the pixel electrode, and the like are formed by a droplet discharge method, but by using various printing methods such as a screen printing method and a gravure printing method and an atmospheric pressure plasma apparatus. It may be formed.

  Next, a manufacturing method different from the specific example shown in FIGS. 8 and 9 will be described with reference to FIGS.

  In the example shown in FIG. 10, first, a separation layer 201, a first insulating film 202, a second insulating film 203, a semiconductor film 204, a gate insulating film 205, a gate electrode 206, an interlayer insulating film 207, and the like are formed over a substrate 200. It is provided and peeled from the substrate 200. Thereafter, the peeled substrate is transferred to a flexible substrate, and a source or drain electrode, a wiring, a pixel electrode, a light emitting layer, a counter electrode, and the like are formed. A specific manufacturing method will be described below.

  First, the separation layer 201, the first insulating film 202, the second insulating film 203, the semiconductor film 204, the gate insulating film 205, the gate electrode 206, and the interlayer insulating film 207 are formed over the substrate 200 (FIG. 10A). )).

  After that, an opening 241 for introducing an etchant and a contact hole 242 reaching the source region or the drain region of the semiconductor layer 204 are formed at the same time. The opening 241 is preferably formed in a portion avoiding a semiconductor film, a wiring or an electrode to be formed later.

  Subsequently, the peeling layer 201 is removed by introducing an etching agent. The separation layer 201 may be completely removed, but here, the separation layer 201 is completely removed so that an element formation portion 243 (hereinafter referred to as an element formation portion 243) constituting the display device is not peeled off from the substrate 200. Is not removed and a part is left (FIG. 10B).

  Next, the first sheet material 214 is adhered to one surface (the surface of the interlayer insulating film 207) of the element formation portion 243, and the element formation portion 243 is peeled from the substrate 200 (FIG. 10C).

  Subsequently, the second sheet material 216 is bonded to the surface of the element forming portion 243 opposite to the surface to which the first sheet material 214 is bonded, so that the thin film element forming portion 243 is removed from the first sheet material 214. Peel off (FIG. 10D). In this manner, the substrate 200 can be replaced with a flexible substrate by performing peeling twice. Of the two peelings, the first sheet material used for the first peeling is preferably peeled off after adhering to the element forming portion 232, so that the first sheet material is weak.

  Thereafter, as shown in FIGS. 11A to 11C, source or drain electrodes 235 and 236, wirings 237, pixel electrodes 238, light emitting layers 217, and counter electrodes 218 are formed, and then the second sheet material 216 is formed. By sealing with the third sheet material 220, a film-like display device can be completed. Note that before the light-emitting layer 217 is formed, an insulating film or the like may be formed in the opening 241 so that the light-emitting layer is formed over the entire pixel region.

  As described above, two specific examples have been described as to which part of the display device is to be formed when part of the display device is formed on the substrate before peeling, but the present invention is not limited to this. Any configuration may be provided before the operation.

  Note that this embodiment mode can be freely combined with the above embodiment modes.

(Embodiment 4)
In this embodiment, the case where one display device is formed by connecting display devices provided over different substrates is described. Specifically, after a part of each of the plurality of substrates constituting the display device is provided, the substrate is arranged, and then a part of the display device provided on the plurality of substrates is peeled off from the substrate and the rest One display device is manufactured by forming a portion of the display device. This will be described below with reference to the drawings. Note that parts that are the same as those shown in the above embodiment are denoted by the same reference numerals.

  First, as illustrated in FIG. 12A, FIGS. 13 and 14 illustrate a configuration of a pixel region in a case where pixel regions 351a and 351b provided on two different substrates 300a and 300b are connected to each other.

  First, as shown in the above embodiment mode, the same structure as that in FIG. 6C is provided over the substrates 300a and 300b, respectively (FIG. 13A). Note that a cross-sectional view taken along a line AB in FIG. 12B corresponds to a line A-B in FIG.

  Subsequently, using a control means such as a CCD camera, the substrate 300a and the substrate 300b are arranged, and the substrate 300a and the substrate 300b are joined together with an adhesive 356 (FIG. 13B). Here, the adhesive 356 adheres only to the substrates 300a and 300b, and does not adhere to the element formation portions 215a and 215b (hereinafter referred to as element formation portions 215a and 215b) constituting the display device provided on the substrates 300a and 300b. To. At this time, an interval (hereinafter referred to as a connection interval 355) is generated between the substrate 300a and the substrate 300b. The position of the element formation portion formed over the substrate 300a and the substrate 300b is adjusted so that the connection interval 355 is located between the pixels of the display device to be formed later. Note that the substrates 300a and 300b may be arranged without using an adhesive when there is no fear that they are displaced. Further, the ends of the substrates may be cut and joined. The connection interval 355 may be provided so as to be larger than between the pixel electrodes in the substrate 300a or between the pixel electrodes in the substrate 300b because of the connection between the substrates 300a and 300b. Preferably, it is provided so as to be the same as between the pixel electrodes.

  Thereafter, the first sheet material 214 is adhered to the surfaces of the element forming portions 215a and 215b provided on the substrate 300a and the substrate 300b, and the element forming portions 215a and 215b are peeled off from the substrates 300a and 300b (FIG. 13 ( C)).

  Subsequently, the element forming portion bonded to the first sheet material 214 by bonding the second sheet material 216 to the surface opposite to the surface bonded to the first sheet material 214 of the element forming portions 215a and 215b. 215a and 215b are peeled off (FIG. 13D).

  After that, as described in the above embodiment mode, the light-emitting layer 217 and the counter electrode 218 are formed (FIG. 14A). At this time, an insulating film or the like may be selectively formed in the opening 213 and the connection interval 355. In this way, by filling the opening 213 and the connection interval 355 with the same substance, the boundary generated when different substrates are connected can be made inconspicuous.

  Next, the element forming portion in which the light emitting layer 217 and the counter electrode 218 are formed is sealed with the second sheet material 216 and the third sheet material 220, thereby completing the film display device (FIG. 14 ( B)). Note that as described above, the protective film 219 is preferably formed over the counter electrode 218 before the third sheet material is bonded. At this time, if nothing is formed in the opening 213 and the connection interval 355, the opening 213 and the connection interval 355 are formed so as to be filled with a protective film.

  In general, when a single display device is formed by connecting a plurality of display devices, a gap (border) is generated between the substrates to be connected, and the boundary is conspicuous as a defect when displaying an image. There is. However, in this embodiment, the boundary can be made inconspicuous by controlling and connecting the connection interval 355 so as to have the same width as that between the pixels (here, the opening 213). Further, after two different substrates 300a and 300b are bonded, a part of the display device formed over the substrate is peeled off from the substrate and newly provided over the flexible substrate. Since it is provided as a substrate, it becomes possible to make the boundary inconspicuous.

  In this manner, a large film display device can be formed by connecting one display device separately provided on two substrates to form one display device.

  Here, an example (corresponding to FIGS. 6 and 7) in which a partition wall is formed on a substrate and then peeled is shown, but the present invention can be similarly applied to the configurations shown in FIGS. .

  Next, as shown in FIG. 15, FIGS. 16 and 17 illustrate a configuration of a pixel region in a case where pixel regions 451 a to 451 d provided on different substrates 450 a to 450 d are connected. Here, the connection portion between the pixel region 451b and the pixel region 451d will be specifically described.

  First, as shown in the above embodiment mode, a structure similar to that in FIG. 10B is provided over the substrates 450a to 450b (FIG. 16A). Thereafter, the substrates 450a to 450d are accurately arranged using a control means such as a CCD camera, and the adjacent substrates are joined together with an adhesive 456 (FIG. 16B). Here, the adhesive 456 is adhered only to the substrates 450a to 450d, and is not adhered to the element forming portions 243a to 243d constituting the display device provided on the substrates 450a to 450b.

  Next, the first sheet material 214 is bonded to the surface of the element formation portions 243a to 243d provided on the substrates 450a to 450d, and the element formation portions 243a to 243d are peeled from the substrates 450a to 450d (FIG. 16 ( C)).

  Subsequently, the element forming portion bonded to the first sheet material 214 by bonding the second sheet material 216 to the surface of the element forming portions 243a to 243d opposite to the surface bonded to the first sheet material 214. 243a to 243d are peeled off (FIG. 16D).

  Next, a source or drain electrode, a wiring, a pixel electrode, a light emitting layer, a counter electrode, and the like are formed on the element formation portions 243a to 243d provided on the second sheet material 216 by using a processing unit.

  First, an insulator is formed in the connection interval 455 formed between the adjacent element formation portions 243a to 243d when the substrates are connected (FIG. 17A). Here, the insulating film 457 is formed by selectively discharging a composition containing an insulator in the connection interval 455 by a droplet discharge method. As the insulator to be discharged, a resin material such as an epoxy resin, an acrylic resin, a phenol resin, a novolac resin, an acrylic resin, a melamine resin, or a urethane resin can be used. In addition, when using these resin materials, the viscosity is good to adjust by melt | dissolving or disperse | distributing using a solvent. Further, as the liquid repellent material, a resin containing a fluorine atom, a resin composed only of hydrocarbon, or the like can be used. More specifically, a resin containing a monomer containing a fluorine atom in the molecule, or a resin containing a monomer composed entirely of carbon and hydrogen atoms can be given. In addition, organic materials such as benzocyclobutene, parylene, flare, permeable polyimide, compound materials made by polymerization of siloxane resins, compositions containing water-soluble homopolymers and water-soluble copolymers, etc. are used. be able to. When an organic material is used, the flatness thereof is excellent, and therefore, even when a conductor is formed later, the film thickness is not extremely reduced at the stepped portion, and disconnection does not occur. .

  Next, source or drain electrodes 235 and 236, a wiring 237, and a pixel electrode 238 are formed (FIG. 17B). In this case, the source or drain electrodes 235 and 236, the wiring 237, and the pixel electrode 238 are formed over the insulating film 457. Therefore, when there are slight uneven steps between the interlayer insulating film 207 and the insulating film 457, the source or drain electrodes 235 and 236, the wiring 237, and the pixel electrode 238 formed over the insulating film 457 are similarly recessed or protruded. There are steps in the part.

  In FIGS. 16 and 17, pixel electrodes are formed in common in element formation portions formed at the end portions of different substrates. Therefore, even when a plurality of display devices are connected, the boundary can be made inconspicuous.

  After that, as shown in the above embodiment mode, a partition wall (bank) 239, a light emitting layer 217, and a counter electrode 218 are formed (FIG. 17C), and the second sheet material 216 and the third sheet material 220 are formed. By sealing, a film display device is completed (FIG. 17D).

  In addition, connection portions of the pixel portions 451a and 451b or 451c and 451d can be connected using the method described above.

  Note that although a method for manufacturing a pixel region by bonding is described in this embodiment mode, the present invention is not limited to the case where the pixel region is bonded, and a circuit (control circuit) that controls the pixel region and the driver circuit or the pixel region is provided. The present invention can also be applied when forming. In other words, the pixel region and the driver circuit or the control circuit can be formed over different substrates in advance, and can be formed on a substrate having common flexibility by being peeled from the substrate. In this case, a wiring for connecting the pixel region to the driver circuit or the control circuit can be formed after being provided over the flexible substrate.

  As described above, by using this embodiment mode, a plurality of substrates can be connected to each other, and a large film display device can be manufactured.

  Note that this embodiment mode can be freely combined with the above embodiment modes.

(Embodiment 5)
In this embodiment, the structure of the light-emitting element is described with reference to FIGS.

  18 includes a first electrode 501 formed over a substrate 500, an electroluminescent layer 502 formed over the first electrode 501, and a second electrode formed over the electroluminescent layer 502. An electrode 503. Note that actually, various layers, semiconductor elements, and the like are provided between the substrate 500 and the first electrode 501.

  In this embodiment, the case where the first electrode 501 is an anode and the second electrode is a cathode is described; however, the first electrode 501 may be a cathode and the second electrode may be an anode.

  The electroluminescent layer 502 is composed of one or more layers. When composed of a plurality of layers, these layers can be classified into a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like from the viewpoint of carrier transport characteristics. Note that the boundaries between the layers are not necessarily clear, and there are cases where the materials constituting the layers are partially mixed and the interface is unclear. For each layer, an organic material or an inorganic material can be used. As the organic material, any of a high molecular weight material, a medium molecular weight material, and a low molecular weight material can be used. The medium molecular weight material corresponds to a low polymer having a number of repeating structural units (degree of polymerization) of about 2 to 20.

  The distinction between a hole injection layer and a hole transport layer is not necessarily strict, and these are the same in the sense that hole transportability (hole mobility) is a particularly important characteristic. For convenience, the hole injection layer is a layer in contact with the anode, and the layer in contact with the hole injection layer is referred to as a hole transport layer to be distinguished. The same applies to the electron transport layer and the electron injection layer. The layer in contact with the cathode is called an electron injection layer, and the layer in contact with the electron injection layer is called an electron transport layer. The light emitting layer may also serve as an electron transport layer, and is also referred to as a light emitting electron transport layer. FIG. 18 illustrates the case where the electroluminescent layer 502 includes the first to fifth layers 504 to 508. The first to fifth layers 504 to 508 are sequentially stacked from the first electrode 501 toward the second electrode 503.

Since the first layer 504 functions as a hole injection layer, it is preferable to use a material having a hole transporting property, a relatively low ionization potential, and a high hole injecting property. Broadly divided into metal oxides, low-molecular organic compounds, and high-molecular organic compounds. As the metal oxide, for example, vanadium oxide, molybdenum oxide, ruthenium oxide, aluminum oxide, or the like can be used. If low molecular weight organic compound, for example, starburst amine typified by m-MTDATA, copper phthalocyanine (abbreviation: Cu-Pc) in the metal phthalocyanine represented, phthalocyanine (abbreviation: H ₂ -Pc), _2, A 3-dioxyethylenethiophene derivative or the like can be used. A film in which a low molecular organic compound and the metal oxide are co-evaporated may be used. As a high molecular organic compound, for example, a polymer such as polyaniline (abbreviation: PAni), polyvinyl carbazole (abbreviation: PVK), or a polythiophene derivative can be used. Polyethylene dioxythiophene (abbreviation: PEDOT), which is one of polythiophene derivatives, doped with polystyrene sulfonic acid (abbreviation: PSS) may be used. Further, a benzoxazole derivative and any one or more materials of TCQn, FeCl ₃ , C _60, or F ₄ TCNQ may be used in combination.

  Since the second layer 505 functions as a hole transport layer, it is desirable to use a known material having high hole transportability and low crystallinity. Specifically, an aromatic amine-based compound (that is, a compound having a benzene ring-nitrogen bond) is suitable, for example, 4,4-bis [N- (3-methylphenyl) -N-phenylamino]. Biphenyl (TPD) and its derivative 4,4′-bis [N- (1-naphthyl) -N-phenyl-amino] biphenyl (α-NPD) are examples. Starburst aromatic amine compounds such as 4,4 ', 4 "-tris (N, N-diphenylamino) triphenylamine (TDATA) and MTDATA can also be used. Alternatively, 4,4 ′, 4 ″ -tris (N-carbazolyl) triphenylamine (abbreviation: TCTA) may be used. As the polymer material, poly (vinyl carbazole) (abbreviation: PVK) or the like which exhibits favorable hole transportability can be used.

Since the third layer 506 functions as a light emitting layer, it is preferable to use a material having a large ionization potential and a large band gap. Specifically, for example, tris (8-quinolinolato) aluminum (Alq ₃ ), tris (4-methyl-8-quinolinolato) aluminum (Almq ₃ ), bis (10-hydroxybenzo [η] -quinolinato) beryllium (BeBq) ₂ ), bis (2-methyl-8-quinolinolato)-(4-hydroxy-biphenylyl) -aluminum (BAlq), bis [2- (2-hydroxyphenyl) -benzoxazolate] zinc (Zn (BOX) ₂ ), Bis [2- (2-hydroxyphenyl) -benzothiazolate] zinc (Zn (BTZ) ₂ ), and the like. Various fluorescent dyes (coumarin derivatives, quinacridone derivatives, rubrene, dicyanomethylene derivatives, 1-pyrone derivatives, stilbene derivatives, various condensed aromatic compounds, etc.) can also be used. Phosphorescent materials such as platinum octaethylporphyrin complex, tris (phenylpyridine) iridium complex, tris (benzylideneacetonato) phenanthrene europium complex can also be used.

  As the host material used for the third layer 506, a hole transport material or an electron transport material typified by the above example can be used. Alternatively, a bipolar material such as 4,4′-N, N′-dicarbazolylbiphenyl (abbreviation: CBP) can be used.

Since the fourth layer 507 functions as an electron transporting layer, a material having a high electron transporting property is preferably used. Specifically, a metal complex having a quinoline skeleton or a benzoquinoline skeleton represented by Alq ₃ or a mixed ligand complex thereof can be used. Specifically, metal complexes such as Alq ₃ , Almq ₃ , BeBq ₂ , BAlq, Zn (BOX) ₂ , and Zn (BTZ) ₂ can be given. In addition to metal complexes, 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (PBD), 1,3-bis [5- (p Oxadiazole derivatives such as -tert-butylphenyl) -1,3,4-oxadiazol-2-yl] benzene (OXD-7), 3- (4-tert-butylphenyl) -4-phenyl-5 -(4-biphenylyl) -1,2,4-triazole (TAZ), 3- (4-tert-butylphenyl) -4- (4-ethylphenyl) -5- (4-biphenylyl) -1,2, Triazole derivatives such as 4-triazole (p-EtTAZ), imidazole derivatives such as TPBI, phenanthroyl such as bathophenanthroline (BPhen) and bathocuproin (BCP) It can be used derivatives.

Since the fifth layer 508 functions as an electron injection layer, it is preferable to use a material having a high electron injection property. Specifically, an ultra-thin film of an insulator such as an alkali metal halide such as LiF or CsF, an alkaline earth halide such as CaF ₂ , or an alkali metal oxide such as Li ₂ O is often used. In addition, alkali metal complexes such as lithium acetylacetonate (abbreviation: Li (acac) and 8-quinolinolato-lithium (abbreviation: Liq) are also effective. Molybdenum oxide (MoOx), vanadium oxide (VOx), A metal oxide or benzoxazole derivative of ruthenium oxide (RuOx), tungsten oxide (WOx), etc. (x> 0) and one or more materials of alkali metal, alkaline earth metal, or transition metal In addition, titanium oxide may be used.

  In the light-emitting element having the above structure, light is applied from the third layer 506 by applying a voltage between the first electrode 501 and the second electrode 503 and supplying a forward bias current to the electroluminescent layer 502. And the light can be extracted from the first electrode 501 side or the second electrode 503 side. Note that the electroluminescent layer 502 is not necessarily required to have all of the first to fifth layers. In the present invention, it is only necessary to include at least the third layer 506 functioning as a light emitting layer. Further, light emission is not necessarily obtained only from the third layer 506, and light emission may be obtained from layers other than the third layer 506 depending on the combination of materials used for the first to fifth layers. Further, a hole blocking layer may be provided between the third layer 506 and the fourth layer 507.

  Note that depending on the color, the phosphorescent material can have a lower driving voltage and higher reliability than the fluorescent material. Therefore, when performing full color display using light emitting elements corresponding to the three primary colors (R, G, B), a combination of a light emitting element using a fluorescent material and a light emitting element using a phosphorescent material, You may make it arrange | equalize the degree of deterioration in the light emitting element of each color.

  FIG. 18 illustrates the case where the first electrode 501 is an anode and the second electrode 503 is a cathode. However, when the first electrode 501 is a cathode and the second electrode 503 is an anode, The fifth layers 504 to 508 are stacked in reverse. Specifically, a fifth layer 508, a fourth layer 507, a third layer 506, a second layer 505, and a first layer 504 are sequentially stacked over the first electrode 501.

  Note that a material that is difficult to be etched is used for the layer closest to the second electrode 503 in the electroluminescent layer 502 (the fifth layer 508 in this embodiment), so that the second electrode is formed over the electroluminescent layer 502. When forming the layer 503 by a sputtering method, sputtering damage given to the layer closest to the second electrode 503 can be reduced. Examples of materials that are difficult to etch include metal oxides such as molybdenum oxide (MoOx), vanadium oxide (VOx), ruthenium oxide (RuOx), and tungsten oxide (WOx) (x> 0), or benzoxazole derivatives A metal thin film can be used. These are preferably formed by vapor deposition.

For example, in the case where the first electrode is a cathode and the second electrode is an anode, the above-described material that is not easily etched is used as the layer having hole injecting property or hole transporting property that is closest to the anode among the electroluminescent layers. Specifically, when a benzoxazole derivative is used, a layer including the benzoxazole derivative and any one or more materials of TCQn, FeCl ₃ , C _60, or F ₄ TCNQ is positioned closest to the anode. Form.

  In addition, for example, when the first electrode is an anode and the second electrode is a cathode, the above-described material that is not etched easily is used as the layer having the electron injecting property or the electron transporting property closest to the cathode among the electroluminescent layers. . Specifically, in the case of using molybdenum oxide, a layer containing the molybdenum oxide and one or more materials of alkali metal, alkaline earth metal, or transition metal is closest to the cathode. Form. In the case of using a benzoxazole derivative, a layer including the benzoxazole derivative and one or more materials of an alkali metal, an alkaline earth metal, or a transition metal is formed so as to be closest to the cathode. Note that a metal oxide and a benzoxazole derivative may be used together.

  With the above structure, as the second electrode, a transparent conductive film formed by sputtering, for example, indium tin oxide (ITO), indium tin oxide containing silicon (ITSO), indium oxide with 2 to 20 atomic% of zinc oxide Even when IZO (Indium Zinc Oxide) mixed with (ZnO) or the like is used, sputter damage to a layer containing an organic substance included in the electroluminescent layer can be suppressed, and selection of a material for forming the second electrode Sex spreads.

  Note that this embodiment mode can be freely combined with the above embodiment modes.

(Embodiment 6)
A circuit of a pixel portion of the display device of the present invention having a display function will be described with reference to FIG. FIG. 19A shows an equivalent circuit diagram of a pixel. The pixel is a video signal for the pixel 6101 in an area surrounded by signal wiring 6114, power supply lines 6115 and 6117, and a scanning line 6116. A TFT 6110 for controlling signal input, a TFT 6111 for controlling a current value flowing between both electrodes of the light emitting element 6113, and a capacitor element 6112 for holding a gate-source voltage of the TFT 6111 are provided. Note that although the capacitor 6112 is illustrated in FIG. 19B, the capacitor 6112 is not necessarily provided when it can be covered by the gate capacitance of the TFT 6111 or other parasitic capacitance.

  FIG. 19B illustrates a pixel circuit in which a TFT 6118 and a scan line 6119 are newly provided in the pixel illustrated in FIG. The arrangement of the TFT 6118 can forcibly create a state in which no current flows through the light-emitting element 6113. Therefore, the lighting period is started at the same time as or immediately after the start of the writing period without waiting for signal writing to all pixels. be able to. Therefore, the duty ratio is improved, and moving images can be displayed particularly well.

FIG. 19C illustrates a pixel circuit in which the TFT 6111 of the pixel 6101 illustrated in FIG. 19B is deleted and TFTs 6125 and 6126 and a wiring 6127 are newly provided. In this configuration, the gate electrode of the TFT 6125 is connected to the wiring 6127 which is held at a constant potential, so that the potential of the gate electrode is fixed and the TFT 6125 is operated in the saturation region. In addition, a video signal that transmits information on lighting or non-lighting of a pixel is input to the gate electrode of the TFT 6126 that is connected in series with the TFT 6125 and operates in a linear region through the TFT 6110. Since the value of the voltage between the source and the drain of the TFT 6126 operating in the linear region is small, a slight change in the voltage between the gate and the source of the TFT 6126 does not affect the value of the current flowing through the light emitting element 6113. Therefore, the value of current flowing through the light emitting element 6113 is determined by the TFT 6125 operating in the saturation region. Note that the channel length L ₁ and channel width W _{1 of} the TFT 6125 and the channel length L ₂ and channel width W ₂ of the TFT 6126 are set so as to satisfy L ₁ / W ₁ : L ₂ / W ₂ = 5 to 6000: 1. Good. Further, it is preferable in the manufacturing process that both TFTs have the same conductivity type. Further, as the TFT 6125, not only an enhancement type but also a depletion type TFT may be used.

  As a driving method for displaying a multi-tone image on a display device, there are analog driving using an analog video signal and digital driving using a digital video signal. The difference between the two methods lies in the method of controlling the light emitting element in each of the light emitting and non-light emitting states of the light emitting element. In the former analog drive, gradation is controlled by controlling the current flowing through the light emitting element. In the latter digital drive, gradation is expressed only by two states, that is, a light emitting element is in an on state (a luminance is almost 100%) and an off state (a luminance is almost 0%). Since only two gradations can be displayed using only two states, on and off, there is a driving method for displaying a multi-gradation image in combination with another method, for example, an area gradation method or time A gradation method is mentioned.

  However, when a digital video signal is used, it differs depending on whether the video signal uses voltage or current. That is, when the light emitting element emits light, a video signal input to the pixel includes a constant voltage signal and a constant current signal. A video signal having a constant voltage includes a constant voltage applied to the light emitting element and a constant current flowing through the light emitting element. In addition, a video signal having a constant current includes a constant voltage applied to the light emitting element and a constant current flowing in the light emitting element. A constant voltage applied to the light emitting element is constant voltage driving, and a constant current flowing through the light emitting element is constant current driving. In constant current driving, a constant current flows regardless of the resistance change of the light emitting element.

  The display device of the present invention may use either analog driving or digital driving regardless of whether it is a liquid crystal panel or a panel using a light-emitting element. May be applied. In addition, other driving methods not mentioned in this embodiment may be applied. Further, either constant voltage driving or constant current driving may be used.

  Note that the display device may be either an active matrix type or a passive matrix type. However, when the active matrix type is applied, the light-emitting element is a current-driven element, and thus it is preferable to use analog driving when there is little variation in transistors in the pixel.

  Note that this embodiment mode can be freely combined with the above embodiment modes.

(Embodiment 7)
In this embodiment mode, applications of the film display device described in the above embodiment mode will be described. The film display device manufactured by the manufacturing method or manufacturing apparatus of the present invention can be used for display portions of various electronic devices. An example is shown in FIG.

  FIG. 20A illustrates a display, which includes a main body 4101, a support base 4102, and a display portion 4103. The display portion 4103 is formed using a flexible substrate, and a lightweight and thin display can be realized. In addition, the display portion 4103 can be curved, and the display portion 4103 can be detached from the support base 4102 and hung on a wall. A display can be manufactured by using the manufacturing method or manufacturing apparatus described in the above embodiment mode for processing the display portion 4103.

  FIG. 20B illustrates a large display that can be wound, which includes a main body 4201 and a display portion 4202. Since the main body 4201 and the display portion 4202 are formed using a flexible substrate, the display can be folded and rolled up and carried. By using the manufacturing method or the manufacturing apparatus described in the above embodiment mode for processing the display portion 4202, a light-weight and thin large display can be manufactured.

  FIG. 20C illustrates a sheet-type computer including a main body 4401, a display portion 4402, a keyboard 4403, a touch pad 4404, an external connection port 4405, a power plug 4406, and the like. The display portion 4402 is formed using a flexible substrate, and a lightweight and thin computer can be realized. Further, by providing a storage space in the power plug 4406, the display portion 2402 can be wound and stored. A computer can be manufactured by using the manufacturing method or the manufacturing apparatus described in the above embodiment for the display portion 4402.

  FIG. 20D illustrates a display device having a large display portion of 20 to 80 inches, which includes a housing 4300, a keyboard portion 4301 that is an operation portion, a display portion 4302, a speaker portion 4303, and the like. In addition, the display portion 4302 is formed using a flexible substrate, and the keyboard portion 4301 can be detached and the housing 4300 can be folded and rolled up to be carried. A large display device can be manufactured by using the manufacturing method or manufacturing apparatus described in the above embodiment mode for the display portion 4302.

  FIG. 20E illustrates an electronic book which includes a main body 4501, a display portion 4502, operation keys 4503, and the like. A modem may be built in the main body 4501. The display portion 4502 is formed using a flexible substrate and can be bent. Further, the display portion 4502 can display moving images as well as still images such as characters. An electronic book can be manufactured by using the manufacturing method or the manufacturing apparatus described in the above embodiment for the display portion 4502.

  FIG. 20F illustrates an IC card, which includes a main body 4601, a display portion 4602, a connection terminal 4603, and the like. Since the display portion 4602 has a lightweight and thin sheet shape using a flexible substrate, the display portion 4602 can be attached to the surface of the card. In addition, when the IC card can receive data without contact, information acquired from the outside can be displayed on the display portion 4602. An IC card can be manufactured by using the manufacturing method or the manufacturing apparatus described in the above embodiment mode for the display portion 4602.

  In addition, the film-like display device of the present invention can display information by sticking to various articles. A specific example is shown in FIG.

  FIG. 21A shows a bus including a camera 4707, a sensor 4703, lights 4704, wheels 4705, a windshield 4706, and the like, and 4705 is a driver. The windshield 4706 has a display portion A4700 and a display portion B4701, and displays necessary information. Further, a display portion C4702 is provided on the side surface of the vehicle body, and information can be displayed as a poster or the like. Since the display portion A 4700, the display portion B 4701, and the display portion C 4702 are light and thin sheets using a flexible substrate, they can be attached to the windshield 4706 or the side surface of the vehicle body. The display portion A 4700, the display portion B 4701, and the display portion C 4702 can be manufactured using the manufacturing method or manufacturing apparatus described in the above embodiment modes.

  FIG. 21B shows an example in which the display unit is mounted around the driver's seat of an automobile. The dashboard 4806 is provided with a sound reproducing device, specifically car audio and car navigation. A car audio main body 4804 includes a display portion A 4800, a display portion B 4801, and operation buttons 4805. A display portion C4802 is also provided on the windshield 4803. Since each display device is a lightweight and thin sheet using a flexible substrate, information can be displayed by being attached to each part. Each display device can be manufactured using the manufacturing method or manufacturing apparatus described in the above embodiment modes.

  In addition, although the example of the vehicle was shown here, the film-like display device manufactured by using the present invention can also be used for information such as information display boards at railway stations and airports, advertisement display boards on streets, etc. It can be used everywhere as long as it is a place to display. As described above, the application range of the present invention is extremely wide and can be used for electronic devices and information display means in various fields. Note that this embodiment mode can be freely combined with the above embodiment modes.

10A and 10B illustrate a manufacturing process of a display device of the present invention. The figure which shows the manufacturing apparatus of the display apparatus in this invention. The figure which shows the manufacturing apparatus of the display apparatus in this invention. The figure which shows the manufacturing apparatus of the display apparatus in this invention. FIG. 14 illustrates a structure of a pixel region of a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. FIG. 14 illustrates a structure of a pixel region of a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. FIG. 14 illustrates a structure of a pixel region of a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention. The figure which shows the structure of the light emitting layer in this invention. FIG. 10 shows an example of a circuit diagram of a display device of the present invention. FIG. 13 illustrates an electronic device using a display device of the present invention. FIG. 13 illustrates an electronic device using a display device of the present invention. 4A and 4B illustrate a method for manufacturing a display device of the present invention.

Claims (14)

Forming a release layer on the substrate,
A base insulating film on the release layer, a semiconductor film including a channel region, a source region, and a drain region formed on the base insulating film, and a gate insulating film formed above the channel region of the semiconductor film A gate electrode, an interlayer insulating film formed over the gate electrode, and a source electrode or drain formed on the interlayer insulating film and electrically connected to the source region or the drain region of the semiconductor film Forming an element forming portion having an electrode, a pixel electrode electrically connected to one of the source electrode or the drain electrode, and an insulating film formed to cover an end of the pixel electrode;
Forming an opening reaching the peeling layer in the insulating film, the interlayer insulating film, the gate insulating film, and the base insulating film to expose the peeling layer;
Introducing an etchant into the opening to remove the release layer;
Using the first roller, the first sheet material is adhered to one surface of the element forming portion, and the element forming portion is peeled from the substrate,
Using the second roller, the second sheet material is adhered to the other surface of the element forming portion, and the element forming portion is peeled off from the first sheet material,
After peeling off the first sheet material, a light emitting layer and a counter electrode are formed on the pixel electrode using processing means,
Forming a protective film on the counter electrode;
Using a third roller, the third sheet material is adhered and sealed to the surface of the protective film,
By rotating the first, second, and third rollers, the display device performs continuously from peeling using the first roller to sealing using the third roller. Manufacturing method. Forming a release layer on the substrate,
A semiconductor film including a channel region, a source region, and a drain region is formed over the peeling layer through a base insulating film,
Forming a gate insulating film covering the semiconductor film;
Forming an opening reaching the release layer in the gate insulating film and the base insulating film to expose the release layer;
Introducing an etchant into the opening to remove the release layer;
Using the first roller, the first sheet material is adhered to the gate insulating film, and the base insulating film, the semiconductor film and the gate insulating film are peeled from the substrate,
Using a second roller, the second sheet material is adhered to the base insulating film, and the base insulating film, the semiconductor film, and the gate insulating film are peeled from the first sheet material,
After peeling off the first sheet material, a processing means is used to form a gate electrode on the gate insulating film so as to be disposed on the channel region of the semiconductor film,
Covering the gate electrode, forming an interlayer insulating film,
Forming a source electrode or a drain electrode electrically connected to the source region or the drain region of the semiconductor film on the interlayer insulating film;
Forming a pixel electrode electrically connected to one of the source electrode or the drain electrode;
Covering the end of the pixel electrode to form an insulating film;
Forming a light emitting layer and a counter electrode on the pixel electrode;
Forming a protective film on the counter electrode;
Using a third roller, the third sheet material is adhered and sealed to the surface of the protective film,
By rotating the first, second, and third rollers, the display device performs continuously from peeling using the first roller to sealing using the third roller. Manufacturing method. Forming a release layer on the substrate,
A semiconductor film including a channel region, a source region, and a drain region is formed over the peeling layer through a base insulating film,
Forming a gate electrode over the channel region of the semiconductor film via a gate insulating film;
Forming an interlayer insulating film covering the gate electrode;
Forming an opening reaching the peeling layer in the interlayer insulating film, the gate insulating film and the base insulating film to expose the peeling layer;
Introducing an etchant into the opening to remove the release layer;
Forming an opening reaching the source region or the drain region of the semiconductor film in the interlayer insulating film and the gate insulating film;
Using a first roller, the first sheet material is adhered to the interlayer insulating film, and the base insulating film, the semiconductor film, the gate insulating film, the gate electrode, and the interlayer insulating film are bonded from the substrate. Exfoliate,
Using a second roller, a second sheet material is bonded to the base insulating film, and the base insulating film, the semiconductor film, the gate insulating film, the gate electrode, and the gate electrode are formed from the first sheet material. Strip the interlayer insulation film,
After peeling off the first sheet material, using a processing means, a source electrode or a drain electrode that is electrically connected to the source region or the drain region of the semiconductor film is formed on the interlayer insulating film,
Forming a pixel electrode electrically connected to one of the source electrode or the drain electrode;
Covering the end of the pixel electrode to form an insulating film;
Forming a light emitting layer and a counter electrode on the pixel electrode;
Forming a protective film on the counter electrode;
Using a third roller, the third sheet material is adhered and sealed to the surface of the protective film,
By rotating the first, second, and third rollers, the display device performs continuously from peeling using the first roller to sealing using the third roller. Manufacturing method. In any one of Claims 1 thru | or 3,
The method for manufacturing a display device is characterized in that the semiconductor film is any one of an amorphous semiconductor film, a film in which an amorphous state and a crystalline state are mixed, a microcrystalline semiconductor film, or a crystalline semiconductor film. In any one of Claims 1 thru | or 4,
The method for manufacturing a display device, wherein the substrate is any one of a glass substrate, a quartz substrate, a ceramic substrate, a metal substrate, and a substrate in which an insulating film is formed on a surface of a semiconductor substrate. In any one of Claims 1 thru | or 5,
A manufacturing method of a display device, wherein the processing means uses a droplet discharge method or a screen printing method. In any one of Claims 1 thru | or 6,
A method for manufacturing a display device, wherein a laminate film or a paper made of a fibrous material is used for the second sheet material. In any one of Claims 1 thru | or 7,
A manufacturing method of a display device, wherein a laminate film or paper made of a fibrous material is used for the third sheet material. In any one of Claims 1 thru | or 8,
One or both of the second sheet material and the third sheet material are provided with a thin film containing carbon as a main component or a film coated with a conductive material. Method. In any one of Claims 1 thru | or 6,
A method for manufacturing a display device, wherein an antistatic film is used for one or both of the second sheet material and the third sheet material. In claim 10,
The method for manufacturing a display device, wherein the antistatic film is a film provided with an antistatic material on one side or both sides thereof. In claim 10,
The method for manufacturing a display device, wherein the antistatic film is a film in which an antistatic material is dispersed in a resin. In any one of Claims 1 to 12,
A method for manufacturing a display device, wherein one or both of pressure treatment and heat treatment is performed using the second roller. In any one of Claims 1 thru / or Claim 13,
A method for manufacturing a display device, wherein one or both of pressure treatment and heat treatment is performed using the third roller.

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