Method of manufacturing flexible device using multidirectional oblique irradiation of an interface between a support substrate and a flexible substrate

A method of manufacturing a flexible device includes joining a first surface of a support substrate to a back surface of a flexible substrate, the first surface being opposite to a second surface of the support substrate; forming an element layer on a front surface of the flexible substrate; and performing multidirectional oblique irradiation of an interface and its vicinity between the support substrate and the flexible substrate with laser light from the second surface of the support substrate to detach the support substrate from the flexible substrate.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Japanese Priority Patent Applications JP2016-105262 filed May 26, 2016 and JP2016-231491 filed Nov. 29, 2016, the entire contents of both of which are incorporated herein by reference.

BACKGROUND

The disclosure relates to a method of manufacturing a flexible device having a flexible substrate and an apparatus for manufacturing such a flexible device.

Various flexible devices have been proposed, in which different element layers are formed on a flexible substrate such as a plastic substrate or a resin substrate. One example of such flexible devices is disclosed in Japanese Unexamined Patent Application Publication No. H10-125930.

SUMMARY

In general, flexible devices as described above are requested for an improvement in their production yield rates. It is desirable to provide a method of manufacturing a flexible device at an improved yield rate and an apparatus for manufacturing such a flexible device.

A method of manufacturing a flexible device according to a first embodiment of the disclosure includes: joining a first surface of a support substrate to a back surface of a flexible substrate, the first surface being opposite to a second surface of the support substrate; forming an element layer on a front surface of the flexible substrate; and performing multidirectional oblique irradiation of an interface and its vicinity between the support substrate and the flexible substrate with laser light from the second surface of the support substrate to detach the support substrate from the flexible substrate.

An apparatus for manufacturing a flexible device according to an embodiment of the disclosure includes an element forming section, and one or more of a plurality of laser light sources. An element forming section forms an element layer on a front surface of a flexible substrate. The flexible substrate has a back surface joined to a first surface of a support substrate. The first surface is opposite to a second surface of the support substrate. One or more of a plurality of laser light sources irradiate an interface and its vicinity between the support substrate and the flexible substrate with laser light from the second surface of the support substrate. Multidirectional oblique irradiation of the interface and its vicinity with the laser light causes the support substrate to be detached from the flexible substrate.

A method of manufacturing a flexible device according to a second embodiment of the disclosure includes: joining a back surface of a flexible substrate to a first surface of a support substrate; forming an element layer on a front surface of the flexible substrate; bringing a second surface of the support substrate into contact with a flowable member, the second surface being opposite to the first surface; and performing irradiation with laser light from the second surface of the support substrate to detach the support substrate from the flexible substrate.

A method of manufacturing a flexible device according to a third embodiment of the disclosure includes: joining a back surface of a flexible substrate to a first surface of a support substrate; forming an element layer on a front surface of the flexible substrate; subjecting a second surface of the support substrate to a surface treatment, the second surface being opposite to the first surface; and performing irradiation with laser light from the second surface of the support substrate to detach the support substrate from the flexible substrate.

DETAILED DESCRIPTION

In the following, some example embodiments of the disclosure are described in detail, in the following order, with reference to the accompanying drawings.

1. First embodiment (an example of a manufacturing method in which multidirectional oblique irradiation with laser light is performed in detaching a support substrate from a display unit)

2. Application Example 1 (an example of application to a manufacturing apparatus)

3. Second embodiment (an example of a manufacturing method in which a second surface of a support substrate is brought into contact with a liquid)

4. Modification Example 1 (an example in which a second surface of a support substrate is brought into contact with a liquid stored in a dam)

5. Modification Example 2 (an example in which a second surface of a support substrate is brought into contact with a high-viscosity material)

6. Modification Example 3 (an example in which a high-viscosity material is cured after being brought into contact with a second surface of a support substrate)

7. Third embodiment (an example of a manufacturing method in which a second surface of a support substrate is subjected to a surface treatment)

8. Application Example 2 (an example of application to an electronic apparatus includes a flexible device)

1. First Embodiment

FIG. 1schematically and cross-sectionally illustrates an example of an overall configuration of a display unit, as a flexible device, according to one embodiment of the disclosure. The display unit is referred to below as a display unit1. The display unit1may be an organic electro-luminescence (EL) device, for example, and has a configuration in which a display element layer13and a protection layer14are provided on a semiconductor unit10in this order. The semiconductor unit10may include a flexible substrate11and a thin film transistor (TFT) layer12provided on a front surface of the flexible substrate11, for example. The combination of the TFT layer12and the display element layer13may correspond to an “element layer” in one specific but non-limiting embodiment of the disclosure.

The flexible substrate11may be made of a resin material, and examples of the resin material may include polyethylene terephthalate (PET), polyimide (PI), polycarbonate (PC), polyethylene naphthalate (PEN), polyamide (PA), and polyethersulfone (PES). In short, the flexible substrate11may be a resin or plastic substrate, for example. However, the constituent material for the flexible substrate11is not limited to any of these resin materials. Alternatively, the flexible substrate11may be made of any other material.

The TFT layer12may be a layer that includes thin-film transistors and other elements. Each of the thin-film transistors may be a top-gate, bottom-gate, or dual-gate thin-film transistor, for example, and may include a semiconductor layer in a selective region of the flexible substrate11. This semiconductor layer may include a channel region or active layer and may be made of an oxide semiconductor that contains, as a major component, an oxide of one or more of elements, including indium (In), gallium (Ga), zinc (Zn), tin (Sn), titanium (Ti), and niobium (Nb), for example. Specific examples of the oxide semiconductor may include indium-tin-zinc oxide (ITZO), indium-gallium-zinc oxide (IGZO: InGaZnO), zinc oxide (ZnO), indium-zinc oxide (IZO), indium-gallium oxide (IGO), indium-tin oxide (ITO), and indium oxide (InO). Alternatively, the semiconductor layer may be made of low-temperature polysilicon (LTPS) or amorphous silicon (a-Si), for example.

The display element layer13may include a plurality of pixels and display elements or light-emitting elements to be driven by a backplane to perform display. The backplane may be provided with a plurality of thin-film transistors therein. Each of the display elements may be an organic EL element or a liquid crystal element, for example. When the display element is an organic EL element, for example, the organic EL element may include an anode electrode, an organic electroluminescent layer, and a cathode electrode, for example, which are provided from the TFT layer12in this order. The anode electrode may serve as a first electrode, the organic electroluminescent layer may serve as a display function layer, and the cathode electrode may serve as a second electrode. The anode electrodes may be coupled to the source-drain electrodes of the above thin-film transistors. A cathode potential common to the pixels may be applied to the cathode electrodes through a wire, for example.

The protection layer14may be a layer that protects the display element layer13from the outside. The protection layer14may be made of an inorganic material, and examples of the inorganic material may include silicon oxide (SiOx), silicon nitride (SiNx), and silicon oxynitride (SiON). Alternatively, the protection layer14may be made of an organic material.

To manufacture the display unit1configured as described above, the flexible substrate11may be joined in advance to a support substrate9, which may be a glass substrate or other suitable substrate, for example, as illustrated in detail inFIG. 2A. More specifically, the support substrate9may have a front surface S1and a back surface S2that are opposite to each other. Herein, the front surface S1may serve as a first surface, and a back surface S2may serve as a second surface. The front surface S1of the support substrate9may be joined to the back surface of the flexible substrate11. Examples of the glass material for the support substrate9may include a quartz glass, a soda glass, and an alkali-free glass.

After formation, on the flexible substrate11, of the individual layers, which may include the TFT layer12, the display element layer13, and the protection layer14, the support substrate9may be detached from the flexible substrate11, for example, as indicated by an arrow P1ofFIG. 2B. More specifically, in this embodiment, an interface and its vicinity between the support substrate9and the flexible substrate11is irradiated with laser light so that the support substrate9is detached from the flexible substrate11, as described later in detail.

The display unit1as described above may be manufactured through the following processing.

First, the front surface S1of the support substrate9described above may be joined to the back surface of the flexible substrate11. Examples of this joining method may include: a method in which a varnish or similar liquid is applied to the support substrate9and then baked; and a method in which the support substrate9is joined to the flexible substrate11with an adhesive layer, for example. A constituent material for the adhesive layer may be siloxane, for example.

After the joining of the support substrate9to the flexible substrate11in the above manner, the element layer, which may include the TFT layer12and the display element layer13, may be formed on the front surface of the flexible substrate11.

More specifically, the semiconductor layer made of one of the above materials, such as an oxide semiconductor, may be formed on the flexible substrate11with a sputtering or other film forming process. Thereafter, the semiconductor layer may be patterned into a predetermined shape with pattern forming processes such as photolithography and etching. Following which, various dielectric films and electrodes may be formed thereon to fabricate the TFT layer12.

Subsequently, the display element layer13may be formed on the TFT layer12. When the display element layer13contains an organic EL element, for example, the display element layer13including anode electrodes, organic electroluminescent layers, and cathode electrodes may be formed on the TFT layer12.

Following the above, the protection layer14made of one of the above materials may be formed on the display element layer13with a chemical vapor deposition (CVD) or other film forming process.

Thereafter, the support substrate9may be detached from the flexible substrate11, for example, as indicated by the arrow P1inFIG. 2B. More specifically, an interface and its vicinity, such as the adhesive layer, between the support substrate9and the flexible substrate11may be irradiated with laser light from the back surface S2of the support substrate9, as described later in detail. In this way, the support substrate9is detached from the flexible substrate11. One exemplary mechanism by which the emission of the laser light cause the support substrate9to be detached from the flexible substrate11is as follows. The emission of the laser light weaken or lose the cohesive strength between atoms or molecules that form the flexible substrate11, or the cohesive strength between atoms or molecules in a substance that forms the above adhesive layer. This results in occurrence of intra-layer detachment or interface detachment.

Through the above processing, the display unit1illustrated inFIG. 1is completed.

The display unit1may drive the pixels in the display element layer13on the basis of an image signal received from the outside, thereby displaying an image. In this case, for example, the thin-film transistors in the TFT layer12may be individually voltage-driven in relation to the respective pixels. More specifically, when a voltage that is equal to or greater than a threshold voltage is supplied to any thin-film transistor, the above semiconductor layer may be activated. In other words, channels may be formed in the semiconductor layer. As a result, currents may flow between pairs of the source-drain electrodes in the thin-film transistors. By voltage-driving the thin-film transistors in this manner, the display unit1may display an image.

COMPARATIVE EXAMPLE

FIGS. 3 to 6illustrate schematically and cross-sectionally a method of manufacturing the display unit1according to a comparative example. The method of manufacturing the display unit1according to the comparative example may be substantially the same as the foregoing method according to the embodiment. Specifically, individual layers that include a TFT layer12, a display element layer13, and a protection layer14may be formed on a flexible substrate11. Thereafter, laser light irradiation may be utilized so that a support substrate9is detached from the flexible substrate11.

More specifically, an interface and its vicinity between the support substrate9and the flexible substrate11may be irradiated with laser light L in the vertical direction from a back surface S2of the support substrate9, for example, as illustrated inFIG. 3. As a result, the support substrate9may be detached from the flexible substrate11throughout a region A101irradiated with the laser light L, for example, as illustrated inFIG. 4. In this example, the irradiated region A101may correspond to the entire region of the interface between the support substrate9and the flexible substrate11.

When a foreign object8is present on the support substrate9, especially on the back surface S2of the support substrate9, for example, as illustrated inFIG. 5, the following disadvantage may arise in the display unit1according to the comparative example when the support substrate9is detached from the flexible substrate11using the laser light L. It is to be noted that, when a flaw is present on the back surface S2of the support substrate9instead of the foreign object8, a similar disadvantage may arise.

In this case, a region A102irradiated with the laser light L and a region A103unirradiated with the laser light L due to the foreign object8may be formed in the interface between the support substrate9and the flexible substrate11, for example, as illustrated inFIG. 6. In other words, the unirradiated region A103corresponds to a region hidden behind the foreign object8when the display unit1is irradiated with the laser light L. The unirradiated region A103formed in this manner may make the support substrate9unlikely or difficult to be detached from the flexible substrate11. That is, a region that is difficult to be detached may be partially formed in the interface between the support substrate9and the flexible substrate11. Thus, using the method, the method of manufacturing the display unit1according to the comparative example may result in a decrease in a manufacturing yield rate.

Embodiment

In contrast, when the support substrate9is detached from the flexible substrate11in the method of manufacturing the display unit1according to this embodiment, the display unit1is irradiated with laser light in the following manner. That is, in this embodiment, an interface and its vicinity between the support substrate9and the flexible substrate11may be irradiated obliquely with the laser light in multi-directions, namely, in two or more directions from the back surface S2of the support substrate9. The support substrate9thereby may be detached from the flexible substrate11.

More specifically, the interface and its vicinity between the support substrate9and the flexible substrate11may be irradiated obliquely with laser light from the back surface S2of the support substrate9, for example, as illustrated inFIG. 7. This process is referred to as a first oblique laser light irradiation. More particularly, in this first oblique laser light irradiation, a first irradiation angle or incident angle θ1of the laser light L1with respect to the interface may be set so as to satisfy the relationship of 0°<θ1<90° (≠90°).

When a foreign object8is present on the support substrate9, especially on the back surface S2of the support substrate9, in the same manner as the above comparative example, as illustrated inFIG. 7, a region A11irradiated with the laser light L1and a region A12unirradiated with the laser light L1due to the foreign object8may be formed in the interface between the support substrate9and the flexible substrate11, for example, as illustrated inFIG. 8. In this embodiment, however, the interface is irradiated obliquely with the laser light L1, unlike the laser light in the comparative example. Therefore, the foreign object8on the support substrate9is misaligned from the unirradiated region A12in the interface, in accordance with the magnitude of the irradiation angle θ1.

Subsequently, the interface and its vicinity between the support substrate9and the flexible substrate11may be irradiated again obliquely with laser light L2from the back surface S2of the support substrate9, for example, as illustrated inFIG. 9. This process is referred to as a second oblique laser light irradiation. More Particularly, in this second oblique laser light irradiation, a second irradiation angle θ2, which is different from the first irradiation angle θ1, of the laser light L2with respect to the interface may be set so as to satisfy the relationship of 0°<θ2<90° (≠90°). By setting the first irradiation angle θ1and the second irradiation angle θ2to have different values (θ1≠θ2), it is possible to achieve multidirectional oblique laser light irradiation.

Also when the second oblique laser light irradiation is performed, a region A21irradiated with the laser light L2and a region A22unirradiated with the laser light L2due to the foreign object8may be formed in the interface between the support substrate9and the flexible substrate11, for example, as illustrated inFIG. 10. However, the first irradiation angle θ1and the second irradiation angle θ2are set to have different values, as described above. This reduces or eliminates any region unirradiated with both of the laser light L1and the laser light L2, namely, any region not irradiated at all with the laser light, in the entire interface between the support substrate9and the flexible substrate11. In the example ofFIG. 10, there is no region that is unirradiated with both of the laser light L1and the laser light L2in the entire region of the interface.

In this embodiment, as described above, the interface and its vicinity between the support substrate9and the flexible substrate11is irradiated obliquely with laser light in multi-directions. The support substrate9is thereby detached from the flexible substrate11. This method reduces or eliminates formation of any laser-light-unirradiated region due to the foreign object or flaw, for example, even when any foreign object or flaw is present on the support substrate9. As a result, a region where the support substrate9is difficult to be detached from the flexible substrate11is unlikely or difficult to be formed in the interface between the support substrate9and the flexible substrate11.

More specifically, according to the foregoing embodiment, multidirectional oblique irradiation with laser light is performed, for example, as illustrated inFIG. 11. That is, for example, regions A11irradiated with the laser light L1and regions A21irradiated with the laser light L2, each of which is linear or rectangular in shape, are sequentially displaced from one another in a direction along a plane in the vicinity of the interface between the support substrate9and the flexible substrate11, as indicated by an arrow P3ofFIG. 11. In this manner, the display unit1is irradiated obliquely with the laser light L1and the laser light L2, as indicated by an arrow P2ofFIG. 11. In other words, for example, the display unit1may be scanned and irradiated with the laser light L1and the laser light L2in oblique directions, in such a way that the irradiated regions A11and A21, each of which is linear in shape, are sequentially displaced from one another.

To perform such multidirectional oblique irradiation with laser light, for example, one or a plurality of laser light sources may be used for the laser light irradiation. Furthermore, this multidirectional oblique laser light irradiation may be performed at a single step or at multiple steps, as described later in detail in Application Example 1.

In this embodiment, as described above, an interface and its vicinity between the support substrate9and the flexible substrate11is irradiated obliquely with laser light in multi-directions. The support substrate9is thereby detached from the flexible substrate11. This method makes it possible to reduce or eliminate the risk of any laser-light-unirradiated region being formed due to a foreign object or flaw on the support substrate9. Consequently, it is possible to manufacture the display unit1at an improved yield rate.

Next, a description is given of Application Example 1 in which the method of manufacturing the display unit1according to the foregoing embodiment is applied to manufacturing apparatuses. In other words, a description is given of the apparatuses for manufacturing the display unit1for achieving the method of manufacturing the display unit1described in the first embodiment. In the following description, the same components as those in the foregoing embodiment are given the same reference numerals, and description therefor is omitted where appropriate.

FIRST EXAMPLE

FIG. 12schematically illustrates a first example of a configuration of an apparatus for manufacturing a flexible device, according to Application Example 1. Thereafter, the manufacturing apparatus is referred to as a manufacturing apparatus4, and the flexible device is referred to as a display unit1.FIG. 12also illustrates an example of a cross-sectional configuration of the display unit1. The manufacturing apparatus4includes an element forming section40, a laser light source41, a beam splitter42, and two mirrors431and432.

The element forming section40may be a mechanical part that forms layers such as element layers, including a TFT layer12, a display element layer13, and a protection layer14in this example, on the front surface of a flexible substrate11through the various forming processes described in the above-described embodiment. In this case, a support substrate9is joined to the back surface of the flexible substrate11.

The laser light source41may be a light source that emits laser light L0from a back surface S2of the support substrate9to an interface and its vicinity between the support substrate9and the flexible substrate11. In this first example, only a single laser light source41may be provided. In this example, the single laser light source41may emit the laser light L0in a direction vertical to the interface between the support substrate9and the flexible substrate11.

The beam splitter42may be an optical member that splits the optical path of the laser light L0emitted from the laser light source41into optical paths extending in multi-directions, i.e., in two directions in this example. More specifically, in this example, the beam splitter42may reflect the laser light L0at substantially right angles, thus splitting the optical path of the laser light L0into the optical paths extending in the two directions.

The mirrors431and432may be optical members that reflect the laser light outputted from the beam splitter42to travel along the optical paths, thereby respectively outputting the above laser light L1and laser light L2to the interface and its vicinity between the support substrate9and the flexible substrate11. This allows multidirectional oblique irradiation with the laser light L1and the laser light L2to be achieved.

The manufacturing apparatus4as configured above irradiates the interface and its vicinity between the support substrate9and the flexible substrate11obliquely with laser light in multi-directions, in the same manner as the foregoing embodiment. The support substrate9is thereby detached from the flexible substrate11. Thus, by manufacturing the display unit1with the manufacturing apparatus4, it is possible to achieve substantially the same effects brought by the workings similar to those in the foregoing embodiment. Specifically, it is possible to reduce or eliminate the risk of any laser-light-unirradiated region being formed due to a foreign object or flaw on the support substrate9. Consequently, it is possible to manufacture the display unit1at an improved yield rate.

In order to irradiate the interface and its vicinity obliquely with the laser light in multi-directions, the manufacturing apparatus4in this first example emits laser light, namely, the original laser light L0only once. More specifically, in order for the manufacturing apparatus4to perform the multidirectional oblique irradiation by emitting the laser light L0only once, the beam splitter42splits the optical path of the laser light L0emitted from the laser light source41into a plurality of optical paths. Therefore, particularly in this example, the manufacturing apparatus4has only to be provided with a single laser light source41. This configuration contributes to a reduction in the cost for members provided in the manufacturing apparatus4.

The manufacturing apparatus4in the first example may be designed such that angles at which the mirrors431and432reflect the laser light are variable, for example, as indicated by arrows P41and P42inFIG. 12, so that the oblique irradiation angles θ1and θ2of the laser light L1and the laser light L2are thereby adjustable. This design enables the locations of a region A11irradiated with the laser light L1and a region A21irradiated with the laser light L2to be finely adjusted, thereby helping an improvement in a production yield rate and providing a user with enhanced usability.

SECOND EXAMPLE

FIG. 13schematically illustrates a second example of the configuration of the apparatus for manufacturing a display unit1according to Application Example 1. The manufacturing apparatus is referred to below as a manufacturing apparatus4A.FIG. 13also illustrates an example of a cross-sectional configuration of the display unit1. The manufacturing apparatus4A may include an element forming section40and a plurality of laser light sources, more specifically two laser light sources411and412.

The laser light source411may be a light source that emits laser light L1to an interface and its vicinity between a support substrate9and a flexible substrate11at an irradiation angle θ1, thereby performing oblique irradiation with the laser light L1. Likewise, the laser light source412may be a light source that emits laser light L2to the interface and its vicinity between the support substrate9and the flexible substrate11at an irradiation angle θ2, thereby performing oblique irradiation with the laser light L2. In this second example, thus, the laser light sources411and412individually emit the laser light L1and the laser light L2, respectively, in oblique directions, thereby performing the multidirectional oblique irradiation with the laser light.

The manufacturing apparatus4A as configured above irradiates the interface and its vicinity between the support substrate9and the flexible substrate11obliquely with laser light in multi-directions, in the same manner as the foregoing embodiment. The support substrate9is thereby detached from the flexible substrate11. Thus, by manufacturing the display unit1with the manufacturing apparatus4A, it is possible to achieve substantially the same effects brought by workings substantially the same as those in the foregoing embodiment. Specifically, it is possible to reduce or eliminate the risk of any laser-light-unirradiated region being formed due to a foreign object or flaw on the support substrate9. Consequently, it is possible to manufacture the display unit1at an improved yield rate.

In the second example, the plurality of laser light sources411and412individually emit, respectively, the laser light L1and the laser light L2in oblique directions, thereby performing multidirectional oblique irradiation with the laser light. More specifically, in order to irradiate the interface and its vicinity obliquely with the laser light in multi-directions, the manufacturing apparatus4A emits the laser light at a single step or at multiple steps. Therefore, in the manufacturing apparatus4A in this second example, the power of each of the laser light L1and the laser light L2emitted, respectively, from the laser light sources411and412may be suppressed to about a half the power emitted from the laser light source41in the foregoing first example. This makes it also possible to save the electricity in the manufacturing apparatus4A.

The manufacturing apparatus4A in the second example may be designed such that angles at which respective orientations or angles of the laser light sources411and412are variable, for example, as indicated by arrows P51and P52inFIG. 13, so that oblique irradiation angles θ1and θ2of the laser light L1and the laser light L2, respectively, are thereby adjustable. This design enables the locations of a region A11irradiated with the laser light L1and a region A21irradiated with the laser light L2to be finely adjusted, thereby helping an improvement in a production yield rate and providing a user with enhanced usability.

THIRD EXAMPLE

FIGS. 14A and 14Bschematically illustrate a third example of the configuration of the apparatus for manufacturing a display unit1according to Application Example 1. The manufacturing apparatus is referred to below as a manufacturing apparatus4B.FIGS. 14A and 14Balso illustrate an example of a cross-sectional configuration of the display unit1. The manufacturing apparatus4B may include an element forming section40and a single laser light source41.

The laser light source41in this third example may be a light source that emits laser light L1at an irradiation angle θ1to an interface and its vicinity between a support substrate9and a flexible substrate11and also emits laser light L2thereto at an irradiation angle θ2. The display unit1thereby may perform the oblique irradiation with the laser light L1and the laser light L2. In this case, the irradiation angles θ1and θ2at which the laser light source41emits, respectively, the laser light L1and the laser light L2may be fixed.

In this third example, the support substrate9may rotate in a direction along its plane between a first oblique irradiation with the laser light L1and a second oblique irradiation with the laser light L2, for example, as indicated by an arrow P6ofFIG. 14B. In conjunction with the rotation of the support substrate9, the whole of the display unit1disposed on the support substrate9may also rotate in the same direction. In this case, for example, the rotational motion of the support substrate9may be made either automatically by a rotation mechanism provided in the manufacturing apparatus4B or manually by a user's operation. In the third example, thus, the support substrate9may rotate in a direction along its plane every time the single laser light source41emits laser light in an oblique direction. This allows for the multidirectional oblique irradiation with the laser light.

The manufacturing apparatus4B as configured above irradiates the interface and its vicinity between the support substrate9and the flexible substrate11obliquely with laser light in multi-directions, in the same manner as the foregoing embodiment. The support substrate9is thereby detached from the flexible substrate11. Thus, by manufacturing the display unit1with the manufacturing apparatus4B, it is possible to achieve substantially the same effects brought by workings substantially the same as those in the foregoing embodiment. Specifically, it is possible to reduce or eliminate the risk of any laser-light-unirradiated region being formed due to a foreign object or flaw on the support substrate9. Consequently, it is possible to manufacture the display unit1at an improved yield rate.

In this third example, the oblique irradiation may be performed by the laser light source41. Subsequently, the support substrate9may rotate in a direction along its plane. Thereafter, another oblique irradiation may be performed by the laser light source41. In this way, the multidirectional oblique laser light irradiation is achieved. Therefore, it is possible to provide the manufacturing apparatus4B in the third example with a simple configuration.

The manufacturing apparatus4B in the third example may be designed such that angles at which an orientation or angle of the laser light source41is variable, for example, as indicated by an arrow P61inFIG. 14Aand an arrow P62inFIG. 14B, so that oblique irradiation angles θ1and θ2of the laser light L1and the laser light L2, respectively, are thereby adjustable. This design enables the locations of a region A11irradiated with the laser light L1and a region A21irradiated with the laser light L2to be finely adjusted, thereby helping an improvement in a production yield rate and providing a user with enhanced usability.

Next, other embodiments and their modification examples are described below. In this description, the same components as those in the foregoing first embodiment are given the same reference numerals, and description therefor is omitted where appropriate e.

3. Second Embodiment

In a method of manufacturing a display unit1according to a second embodiment, a back surface S2of a support substrate9may be brought into contact with a liquid31as a flowable member, as illustrated inFIG. 15. Thereafter, the irradiation with laser light L may be performed. Examples of the liquid31may include cooking oil and an organic solvent. The liquid31may preferably have a refractive index that is closer to that of the constituent material for the support substrate9than a refractive index of air. More preferably, the refractive index of the liquid31may be preferably equal to or substantially equal to a refractive index of the constituent material for the support substrate9. For example, the refractive index of the liquid31may be more than the refractive index of air, i.e., 1.0, but equal to or smaller than the refractive index of the constituent material for the support substrate9. The expression “the refractive index of the liquid31is substantially equal to the refractive index of the constituent material for the support substrate9” may mean that the refractive index of the liquid31falls within the range from about 98% to 100% of the refractive index of the constituent material for the support substrate9. When the support substrate9is made of glass having a refractive index of about 1.52, the refractive index of the liquid31may fall within the range from about 1.49 to 1.52, for example.

Using the liquid31, the display unit1may be manufactured through the following processing, for example.

A front surface S1of the support substrate9may be joined to the back surface of a flexible substrate11, in the same manner as the foregoing first embodiment. After the support substrate9has been joined to the flexible substrate11, an element layer that includes a TFT layer12and a display element layer13may be formed on the front surface of the flexible substrate11. Thereafter, a protection layer14made of any of the above materials may be formed on the display element layer13by a chemical vapor deposition (CVD), for example.

After the protection layer14is formed, the back surface S2of the support substrate9may be brought into contact with the liquid31, for example, as illustrated inFIG. 15. More specifically, the support substrate9, the flexible substrate11, the TFT layer12, the display element layer13, and the protection layer14may be mounted on a stage51and then put into a container52filled with the liquid31. In this case, the support substrate9, for example, may be fixed to the stage51, with the front surface S1facing the stage51and the back surface S2facing the opposite of the stage51. The support substrate9may be sufficiently deeply put into the container52until the whole of the back surface S2is positioned under the surface of the liquid31, so that the whole back surface S2of the support substrate9is brought into contact with the liquid31.

While the back surface S2of the support substrate9is in contact with the liquid31as described above, irradiation with the laser light L may be performed from the back surface S2of the support substrate9. Thereafter, the support substrate9, the flexible substrate11, the TFT layer12, the display element layer13, and the protection layer14are taken out of the container52. Thereafter, the support substrate9is detached from the flexible substrate11, as indicated by the arrow P1ofFIG. 2B.

Through the above processing, the display unit1illustrated inFIG. 1has been completed.

COMPARATIVE EXAMPLE

The method of manufacturing the display unit1according to the second embodiment is compared with the method of manufacturing the display unit1illustrated inFIGS. 3 and 4according to the comparative example. The manufacturing method according to the comparative example may be similar to that according to the second embodiment described above. Specifically, in the manufacturing method according to the comparative example, the individual layers, namely, the TFT layer12, the display element layer13, and the protection layer14may be formed on the flexible substrate11. Thereafter, the support substrate9may be detached from the flexible substrate11utilizing the irradiation with the laser light L.

More specifically, the interface and its vicinity between the support substrate9and the flexible substrate11is irradiated with the laser light L in a vertical direction from the back surface S2of the support substrate9, for example, as illustrated inFIG. 3. As a result of this irradiation, the region A101irradiated with the laser light L, which corresponds to the entire region of the interface between the support substrate9and the flexible substrate11in this example, may be formed, for example, as illustrated inFIG. 4. This enables the support substrate9to be detached from the flexible substrate11. Within this irradiated region A101, the support substrate9may be joined to the flexible substrate11at a weak sticking force.

In some cases, a flaw9C or similar fault is likely to be generated on the back surface S2of the support substrate9during the manufacturing process, for example, as illustrated inFIG. 16. One reason why the flaw9C is likely to be generated on the back surface S2of the support substrate9is that the back surface S2of the support substrate9is brought into contact with a manufacturing apparatus or is exposed to a reagent or to the atmosphere of a reactant gas, during the manufacturing process. Furthermore, there are cases where any foreign object, such as the foreign object8illustrated inFIG. 5, adheres to the back surface S2of the support substrate9. Therefore, when the support substrate9is detached from the flexible substrate11utilizing the laser light L, the following disadvantage may arise in the comparative example.

As illustrated inFIG. 17, when the laser light L incident on a region adjacent to the flaw9C may be refracted, there is a difference in an incident angle of the laser light L between a part without the flaw9C and a part of the flaw9C. Therefore, the laser light L incident on the part of the flaw9C may fail to reach the interface between the support substrate9and the flexible substrate11.

In the above case, as illustrated inFIG. 18, a region A103unirradiated with the laser light L due to the flaw9C may be formed in the interface between the support substrate9and the flexible substrate11. This unirradiated region A103may make the support substrate9unlikely or difficult to be detached from the flexible substrate11. Thus, the method of manufacturing the display unit1according to the comparative example may cause disadvantage at the manufacturing step of detaching the support substrate9from the flexible substrate11. Therefore, this method may lead to a decreased production yield rate of the display unit1. For example, the functions of the display element layer13may be lowered during the manufacturing step of detaching the support substrate9from the flexible substrate11.

FIG. 19Aillustrates a display state of the display unit1before detachment of the support substrate9from the flexible substrate11.FIG. 19Billustrates a display state of the display unit1after the detachment of the support substrate9from the flexible substrate11.FIG. 19Cillustrates a non-light-emitting region ofFIG. 19Bin an enlarged manner. As illustrated inFIGS. 19A to 19C, the flaw9C, a foreign object, and other faults on the back surface S2of the support substrate9may be a cause of any display failure.

FIG. 20Ais a microscope photograph of the front surface S1of the support substrate9.FIG. 20Bis a microscope photograph of the back surface S2of the support substrate9. FromFIGS. 20A and 20B, it is confirmed that the flaw9C, a foreign object, and other faults present on the back surface S2of the support substrate9may be a cause of generating the unirradiated region A103. Methods such as washing may be conceivable as a method for removing foreign objects. However, using the method of washing may be insufficient to remove foreign objects effectively and be unable to remove the flaw9C, thus making it difficult to improve a production yield rate.

Embodiment

In contrast, in the manufacturing method according to the present embodiment, the irradiation with the laser light L may be performed, with the back surface S2of the support substrate9being in contact with the liquid31. Thus, even when the flaw9C is present on the back surface S2of the support substrate9, it becomes possible to allow the laser light L incident on a part of the flaw9C and the laser light L incident on another part to travel in similar manners. This flaw9C may correspond to a “recess” in one specific but non-limiting embodiment of the technology.

More specifically, as illustrated inFIG. 21, when the flaw9C is present on the back surface S2of the support substrate9, the liquid31whose refractive index is equal to or substantially equal to that of the constituent material for the support substrate9may flow into the flaw9C. Thereafter, the flaw9C may be filled with the liquid31. As a result, the laser light L incident on a part of the flaw9C and the laser light L incident on another part may travel inside the support substrate9in similar manners, and then reach the interface between the support substrate9and the flexible substrate11. Consequently, it is possible to lessen influences of the flaw9C over the irradiation with the laser light L.

FIG. 22illustrates the region A101irradiated with the laser light L, which is formed as a result of irradiation with the laser light L, with the back surface S2of the support substrate9being in contact with the liquid31. By irradiation with the laser light L, with the back surface S2of the support substrate9being in contact with the liquid31, it is possible to make the unirradiated region A103unlikely to be formed even when the flaw9C is present on the back surface S2of the support substrate9. This makes it possible to detach the support substrate9from the flexible substrate11without reducing the functions of the element layer, which includes the TFT layer12and the display element layer13.

A description is given of finding results of the relationship between the refractive index of the liquid31and the size of the unirradiated region A103using a simulation.

FIG. 23schematically illustrates the propagation of the laser light L inside the support substrate9when the flaw9C is present on the back surface S2of the support substrate9. An angle A1, which is the angle between the laser light L and a normal PL1to a flaw surface S9, is deemed to be an incident angle of the laser light L. The laser light L may be refracted and then travel inside the support substrate9. Thereafter, the laser light L may reach the interface between the support substrate9and the flexible substrate11. The refracted laser light L may form an angle A2with the normal PL1. The travel direction of the refracted laser light L may form an angle A3with that of the pre-refracted laser light L. A normal PL2extending from the flaw9C to the flexible substrate11, the direction in which the laser light L travels inside the support substrate9, and the interface between the support substrate9and the flexible substrate11may form a right triangle. The side of this right triangle, which coincides with the interface between the support substrate9and the flexible substrate11may correspond to the unirradiated region A103. A size X of the unirradiated region A103may be determined using Expressions (1) to (3) described below.
A3=A1−A2  (1)
n31·sin(A1)=n9·sin(A2)  (2)
X=T1×tan(A3)  (3),

where n31denotes the refractive index of the liquid31, n9denotes the refractive index of the constituent material for the support substrate9, and T1denotes the length of the side of the above right triangle, which coincides with the normal PL2. Expression (2) represents the Snell's law. Moreover, by substituting Expressions (1) and (2) into Expression (3), the size X of the unirradiated region A103may be determined using Expression (4) described below,
X=T1×tan(A1−A2)=T1×tan(A1−sin−1(n31/n9×sinA1)  (4).

The length T1and the angle A1vary depending on a shape of the flaw9C and an incident angle of the laser light L, i.e., the angle A1. Therefore, the relationship between the size X of the unirradiated region A103and each of the length T1and the angle A1is determined using Expression (4).

FIG. 24Aillustrates the relationship between the length T1and the size X of the unirradiated region A103.FIG. 24Billustrates the relationship between the angle A1and the size X of the unirradiated region A103. InFIGS. 24A and 24B, the refractive index n31of the liquid31is set to be equal to a refractive index of air, namely, set to 1.0, and the refractive index n9of the support substrate9is set to be equal to that of glass, namely, set to 1.5. The size X of the unirradiated region A103becomes larger as the length T1becomes closer to the thickness T of the support substrate9, namely, as the angle A1becomes closer to 90°. Thereinafter, the thickness T is set to 500 μm. Thus, a simulation was performed under the condition of the length T1being set to 500 μm and the angle A1being set to 90°.

FIG. 25Aillustrates the simulation results of the relationship between the refractive index n31of the liquid31and the size X of the unirradiated region A103.FIG. 25Billustrates a portion ofFIG. 25Ain the range of the refractive index n31from 1.4 to 1.5, in an enlarged manner. In this simulation, the refractive index n9of the support substrate9is set to be equal to the refractive index of glass, namely, set to 1.5, and the refractive index n31of the liquid31is varied in the range from 1.0 to 1.5. The refractive index n31of the liquid31may be preferably equal to or smaller than the refractive index n9of the support substrate9. This is because, when the refractive index n31of the liquid31exceeds the refractive index n9of the support substrate9, the laser light L may be totally reflected.

When the size X of the unirradiated region A103exceeds 100 μm, the unirradiated region A103is highly prone to cause disadvantage associated with light emission. According toFIGS. 25A and 25B, when the refractive index n31of the liquid31falls within the range from 1.47 to 1.5, the size X of the unirradiated region A103becomes 100 μm or less. In this case, the range of the refractive index n31of the liquid31which may cause the unirradiated region A103to be shrunk more effectively may be specified by expression (5) described below,
n9≥n31≥0.98×n9  (5).

In the present embodiment, as described above, the irradiation with the laser light L may be performed, with the back surface S2of the support substrate9being in contact with the liquid31. Therefore, even when the flaw9C is present on the back surface S2of the support substrate9, the liquid31may flow into the flaw9C. This makes it possible to lessen influences of the flaw9C over the irradiation with the laser light L. Consequently, it is possible to reduce the risk of any disadvantage arising during a process by which the support substrate9is detached from the flexible substrate11, thereby manufacturing the display unit1at an improved yield rate.

FIGS. 26A and 26Beach illustrate one process of a method of manufacturing a display unit1according to Modification Example 1. More specifically,FIG. 26Ais a perspective view of a support substrate9used for this process, andFIG. 26Bis a cross-sectional view of the display unit1. In the process by which the back surface S2of the support substrate9is brought into contact with the liquid31, a dam53may be used instead of the above-described container52.

After a protection layer14is formed as with the process described in the first embodiment, the dam53may be formed on the periphery of the back surface S2of the support substrate9. The dam53may have a planar shape substantially the same as the outline of the support substrate9, namely, may be a rectangular frame. The dam53may be made of a material used for dams, such as a resin. Example of the resin may include a silicone resin and an epoxy resin. Thereafter, the liquid31may be stored inside the dam53. The liquid31thereby may be brought into contact with the back surface S2of the support substrate9. Subsequently, irradiation with the laser light L may be performed from the back surface S2of the support substrate9, with the back surface S2of the support substrate9being in contact with the liquid31. Thereafter, the liquid31and the dam53may be removed, and then the support substrate9may be detached from the flexible substrate11.

FIGS. 27A and 27Beach illustrate one process of a method of manufacturing a display unit1according to Modification Example 2. More specifically,FIG. 27Ais a perspective view of a support substrate9used for this process, andFIG. 27Bis a cross-sectional view of the display unit1. In the process by which the back surface S2of the support substrate9is brought into contact with the liquid31, a high-viscosity material32as a flowable member may be used instead of the liquid31. The high-viscosity material32may be a resin, such as an acrylic resin or an epoxy resin. As with the liquid31, the refractive index of the high-viscosity material32may be preferably equal to or substantially equal to that of the constituent material for the support substrate9.

After a protection layer14is formed with the process described in the first embodiment, the back surface S2of the support substrate9may be coated with the high-viscosity material32. The high-viscosity material32thereby may be brought into contact with the back surface S2of the support substrate9. Subsequently, irradiation with the laser light L may be performed from the back surface S2of the support substrate9, with the back surface S2of the support substrate9being in contact with the high-viscosity material32. Thereafter, the high-viscosity material32may be removed, and then the support substrate9may be detached from the flexible substrate11.

A photo-curable high-viscosity material32, such as an ultraviolet curable material, may be used. Alternatively, a thermosetting high-viscosity material32may be used. When the high-viscosity material32of any of these types is used, the high-viscosity material32may be cured on and fixed to the support substrate9, and then the back surface S2of the support substrate9may be irradiated with the laser light L. The photo-curable or thermosetting high-viscosity material32may be a resin such as an acrylic resin and an epoxy resin.

First, in the same manner as the foregoing Modification Example 2, the back surface S2of the support substrate9may be coated with the high-viscosity material32. Subsequently, the high-viscosity material32may be optically or thermally cured, and then irradiation with the laser light L may be performed from the back surface S2of the support substrate9.

A description is given of a method of manufacturing a display unit1according to a third embodiment of the disclosure, with reference toFIGS. 28A and 28B. In the method of manufacturing the display unit1according to the third embodiment, a back surface S2of a support substrate9may be subjected to a surface treatment, instead of being brought into contact with a liquid, i.e., the liquid31inFIG. 15. With this surface treatment, a treated surface S3that is uniform may be formed, as illustrated inFIG. 28B. The method of manufacturing the display unit1according to the third embodiment is different from the foregoing method of manufacturing the display unit1according to the second embodiment in this technical point.

First, a protection layer14may be formed as with the foregoing method according to the first embodiment. Thereafter, the back surface S2of the support substrate9may be subjected to the surface treatment. Examples of this surface treatment may include an etching treatment using an abrasive and a dissolution treatment. The etching treatment using an abrasive may be a wet blasting method, for example, and the abrasive may be made of aluminum-oxide particles, for example. The dissolution treatment may be a wet etching treatment, for example, and may involve using a solution, such as fluoric acid. With this surface treatment, the whole of the back surface S2of the support substrate9may be polished, so that the back surface S2is formed into the treated surface S3, as illustrated inFIG. 28B. Simultaneously with the polishing of the back surface S2, a flaw9C and a foreign object9D, illustrated inFIG. 28A, that have been present on the back surface S2of the support substrate9may be removed. Thus, the treated surface S3may have uniform roughness. After the treated surface S3is formed, irradiation with laser light L may be performed from the treated surface S3, i.e., the back surface S2, so that the support_substrate9is detached from the flexible substrate11. In this case, the roughness of the treated surface S3may be determined in consideration of the sizes of the flaw9C and the foreign object9D and the propagation efficiency of the laser light L1. For example, as the roughness of the treated surface S3becomes greater, the propagation efficiency of the laser light L may become lower; however, a deeper flaw9C may be able to be removed. The roughness of the treated surface S3may vary depending on the type of an abrasive or a solution, for example.

In this embodiment, the back surface S2of the support substrate9may be subjected to the surface treatment. With this surface treatment, the flaw9C, the foreign object9D, and other faults that have been present on the back surface S2of the support substrate9may be removed, so that the treated surface S3having regular roughness is formed. Thereafter, the uniform treated surface S3may be irradiated evenly with the laser light L. As a result, the energy of the laser light L is transmitted evenly to the interface between the support substrate9and the flexible substrate11. Thus, it becomes possible to lessen influences of the flaw9C, the foreign object9D, and other faults over the irradiation with the laser light L, even when they are present on the back surface S2of the support substrate9. Consequently, it is possible to suppress occurrence of disadvantage at the manufacturing step of detaching the support substrate9from the flexible substrate11, thereby manufacturing the display unit1at an improved yield rate.

Even when the flaw9C, the foreign object9D, and other faults are not removed completely, the treated surface S3may facilitate the scattering of the laser light L, because the treated surface S3is rougher than the back surface S2before being subjected to the surface treatment. This allows the laser light L to reach the whole of the interface between the support substrate9and the flexible substrate11, regardless of whether the flaw9C, the foreign object9D, and other faults are present.

Next, a description is given of Application Example 2 in which the flexible device, such as the display unit1, according to any of the first to third embodiments, Modification Examples 1 to 3, and Application Example 1 is applied to an electronic apparatus.

A description is given of examples of block configurations of a display unit and an imaging unit, which are specific examples of the flexible device of the disclosure.

[Example of Block Configuration of Display Unit1]

FIG. 29schematically illustrates, in a block diagram, an example of an overall configuration of a display unit1as the flexible device. The display unit1may display an image signal outputted from the outside or generated inside, as an image. The display unit1is applicable not only to an organic EL display as described above but also to a liquid crystal display, for example. The display unit1may include a timing controller21, a signal processor22, a driver23, and a display pixel section24, for example.

The timing controller21may have a timing generator that generates various timing signals, which are also referred to as control signals. The timing controller21may control the driving of the signal processor22, for example, on the basis of the various timing signals.

The signal processor22may subject a digital image signal inputted from the outside to a predetermined correction, for example, and may output a resultant image signal to the driver23.

The driver23may include a scanning line drive circuit and a signal line drive circuit, for example, and may drive each pixel of the display pixel section24through various control lines.

The display pixel section24may include: a display element, such as an organic EL element or a liquid crystal element, which correspond to the display element layer13described above; and a pixel circuit that drives the display element on a pixel basis. The semiconductor unit10including the TFT layer12described above is used for various circuits, for example, that constitute a part of the driver23or the display pixel section24among the above constituent elements.

[Example of Block Configuration of Imaging Unit2]

In the first to third embodiments, Modification Examples 1 to 3, and Application Examples 1 and 2, the display unit1has been described as a specific example of the flexible device of the disclosure or as an application example of the semiconductor unit10. However, the flexible device of the disclosure may be implemented using not only the display unit1but also other devices, such as an imaging unit. In other words, the semiconductor unit10may be applied not only to the display unit1but also to an imaging unit.

FIG. 30schematically illustrates, in a block diagram, an example of an overall configuration of an imaging unit2as the flexible device. The imaging unit2may be, for example a solid state imaging unit that acquires an image in the form of an electric signal. The imaging unit2may be configured by a charge coupled device (CCD) or complementary metal oxide semiconductor (CMOS) image sensor, for example. The imaging unit2may include a timing controller25, a driver26, an imaging pixel section27, and a signal processor28, for example.

The timing controller25may have a timing generator that generates various timing signals, which are also referred to as control signals. The timing controller21may control the driving of the driver26on the basis of the various timing signals.

The driver26may include a row selection circuit, an analog-to-digital (AD) conversion circuit, and a horizontal transfer scanning circuit, for example. The driver26may drive the imaging pixel section27so as to read signals from each pixel therein through various control lines.

The imaging pixel section27may include: imaging elements or photoelectric conversion elements, such as photodiodes; and a pixel circuit that reads signals, for example. Examples of such an imaging element may include an element that detects visible light and an element that directly or indirectly detects any of infrared light, ultraviolet light, and radioactive rays such as X rays.

The signal processor28may subject a signal received from the imaging pixel section27to various signal processes. The semiconductor unit10including the TFT layer12described above is used for various circuits, for example, that constitute a part of the driver26or the display pixel section27among the above constituent elements.

[Example of Configuration of Electronic Apparatus]

The flexible devices described in the first to third embodiments, Modification Examples 1 to 3, and Application Examples 1 and 2, which include the display unit1and the imaging unit2provided with the semiconductor unit10, are applicable to various types of electronic apparatuses.

FIG. 31illustrates, in a block diagram, Application Example 2 in which an electronic apparatus includes the display unit1illustrated inFIG. 29or the imaging unit2illustrated inFIG. 30. This electronic apparatus is referred to below as an electronic apparatus3. Examples of the electronic apparatus3may include a television, a personal computer (PC), a smartphone, a tablet PC, a portable phone, a digital still camera, and a digital video camera.

The electronic apparatus3may include the display unit1or the imaging unit2described above and an interface30, for example. The interface30may be an input section that receives various signals and is supplied with electricity from the outside. The interface30may include a user interface, such as a touch panel, a keyboard, or operation buttons.

Hereinabove, the technology of the disclosure has been described using the first to third embodiments and Application Examples 1 and 2. However, the technology is not limited to the first to third embodiments, Modification Examples 1 to 3, and Application Examples 1 and 2, and may be modified in various ways.

For example, factors such as a material and a thickness of each layer exemplified in the foregoing first to third embodiments, Modification Examples 1 to 3, and Application Examples 1 and 2 are illustrative and non-limiting. Any other material, any other thickness, and any other factor may be adopted besides those described above. It is not essential for the semiconductor unit to include all of the layers described above. Alternatively, the foregoing semiconductor unit may further include any other layer in addition to the layers described above.

A technique of the multidirectional oblique irradiation with laser light is not limited to the technique described in the foregoing first to third embodiments, Modification Examples 1 to 3, and Application Examples 1 and 2. Any other techniques may be employed to achieve the multidirectional oblique irradiation.

As a specific example, oblique irradiation with laser light in three or more directions may be performed.

A description has been given, in the foregoing second embodiment, of the case where the support substrate is irradiated with laser light while being mounted in a container. However, the support substrate may be temporarily mounted in the container and then taken out of the container, following which the support substrate may be irradiated with laser light.

A description has been given, in the foregoing second embodiment and Modification Examples 1 to 3, of the case where each of the liquid and the high-viscosity material is used as a flowable member. However, for example, other forms of substance such as a gel substance may also be used as a flowable member.

Various examples described heretofore may be combined as appropriate for application. For example, the back surface of the support substrate may be subjected to a surface treatment, then brought into contact with a flowable member, and irradiated with laser light.

It is to be noted that the effects described herein are mere examples and are not limited thereto, and may include other effects.

Moreover, the technology may also have the following configurations.

A method of manufacturing a flexible device, including:

joining a first surface of a support substrate to a back surface of a flexible substrate, the first surface being opposite to a second surface of the support substrate;

forming an element layer on a front surface of the flexible substrate; and

performing multidirectional oblique irradiation of an interface and its vicinity between the support substrate and the flexible substrate with laser light from the second surface of the support substrate to detach the support substrate from the flexible substrate.

The method of manufacturing the flexible device according to (1), wherein the multidirectional oblique irradiation of the interface and its vicinity is performed at single irradiation with the laser light.

The method of manufacturing the flexible device according to (2), wherein the multidirectional oblique irradiation performed at single irradiation with the laser light includes causing a beam splitter to split an optical path of the laser light emitted from a laser light source into a plurality of optical paths.

The method of manufacturing the flexible device according to (1), wherein the multidirectional oblique irradiation of the interface and its vicinity is performed at multiple irradiation with the laser light.

The method of manufacturing the flexible device according to (4), wherein

an irradiation angle of the laser light with which the oblique irradiation is performed is fixed, and

the multidirectional oblique irradiation performed at the multiple irradiation with the laser light includes:performing the oblique irradiation;rotating the support substrate in an in-plane direction after the performing of the oblique irradiation; andperforming the oblique irradiation again after the rotating of the support substrate.
(6)

The method of manufacturing the flexible device according to any one of (1) to (5), wherein the multidirectional oblique irradiation of the interface and its vicinity is performed using one or more of laser light sources.

The method of manufacturing the flexible device according to any one of (1) to (6), wherein the multidirectional oblique irradiation with the laser light is performed by sequentially moving a linear region irradiated with the laser light in a direction within a plane near the interface.

The method of manufacturing the flexible device according to any one of (1) to (7), wherein an irradiation angle of the laser light at which the oblique irradiation is performed is adjustable.

A method of manufacturing a flexible device, including:

joining a back surface of a flexible substrate to a first surface of a support substrate;

forming an element layer on a front surface of the flexible substrate;

bringing a second surface of the support substrate into contact with a flowable member, the second surface being opposite to the first surface; and

performing irradiation with laser light from the second surface of the support substrate to detach the support substrate from the flexible substrate.

The method of manufacturing the flexible device according to (9), wherein

the second surface of the support substrate is provided with a recess, and

the irradiation with the laser light is performed after filling of the recess with the flowable member.

The method of manufacturing the flexible device according to (9) or (10), wherein the flowable member has a refractive index that is greater than a refractive index of air but is equal to or smaller than a refractive index of a constituent material for the support substrate.

The method of manufacturing the flexible device according to any one of (9) to (11), wherein the flowable member has a refractive index that is equal to or substantially equal to a refractive index of a constituent material for the support substrate.

The method of manufacturing the flexible device according to any one of (9) to (12), wherein the irradiation with the laser light is performed from the second surface of the support substrate, with the second surface of the support substrate being in contact with the flowable member.

A method of manufacturing a flexible device, including:

joining a back surface of a flexible substrate to a first surface of a support substrate;

forming an element layer on a front surface of the flexible substrate;

subjecting a second surface of the support substrate to a surface treatment, the second surface being opposite to the first surface; and

performing irradiation with laser light from the second surface of the support substrate to detach the support substrate from the flexible substrate.

The method of manufacturing the flexible device according to (14), wherein the subjecting of the second surface of the support substrate to the surface treatment forms the second surface of the support substrate into a uniform treated surface.

The method of manufacturing the flexible device according to (15), wherein the treated surface of the support substrate has uniform roughness.

The method of manufacturing the flexible device according to any one of (14) to (16), wherein the surface treatment includes performing an etching treatment using an abrasive.

The method of manufacturing the flexible device according to any one of (14) to (16), wherein the surface treatment includes performing a dissolution treatment.

An apparatus for manufacturing a flexible device, including:

an element forming section that forms an element layer on a front surface of a flexible substrate, the flexible substrate having a back surface that is joined to a first surface of a support substrate, the first surface being opposite to a second surface of the support substrate; and

one or more of a plurality of laser light sources that irradiate an interface and its vicinity between the support substrate and the flexible substrate with laser light from the second surface of the support substrate), wherein

multidirectional oblique irradiation of the interface and its vicinity with the laser light causes the support substrate to be detached from the flexible substrate.

The apparatus for manufacturing the flexible device according to (19), wherein

the one or more of the plurality of laser light sources include a laser light source, and

the apparatus further includes:

a beam splitter that splits an optical path of the laser light emitted from the laser light source into a plurality of optical paths; and

a mirror that performs the multidirectional oblique irradiation by reflecting laser light emitted from the beam splitter and traveling along each of the plurality of optical paths.

In the method of manufacturing the flexible device according to the first embodiment of the disclosure or the apparatus for manufacturing the flexible device according to the embodiment of the disclosure, the interface and its vicinity between the support substrate and the flexible substrate is irradiated obliquely with the laser light in the multi-directions, so that the support substrate is detached from the flexible substrate. Consequently, even when any foreign object or flaw is present on the support substrate, for example, it is possible to reduce or eliminate the risk of formation of a region unirradiated with the laser light which is attributed to the foreign object or flaw.

In the method of manufacturing the flexible device according to the second embodiment of the disclosure, the support substrate is irradiated with the laser light, with the second surface being in contact with the flowable member. This makes it possible to lessen influences of the flaw or recess over the irradiation of the laser light even when any flaw or recess is present on the second surface of the support substance, because the flowable member flows into the flaw or recess. In this case, for example, a refractive index of the flowable member may be set to be equal to or substantially equal to a refractive index of a constituent material for the support substrate. This makes it possible to cause the laser light incident on the flaw and other regions to travel inside the support substrate in similar manners.

In the method of manufacturing the flexible device according to the third embodiment of the disclosure, the support substrate with the second surface subjected to the surface treatment is irradiated with the laser light. This allows the second surface to be formed into a uniformly treated surface, even when any flaw, foreign object, or other faults are present on the second surface of the support substrate, for example. Thus, the flaw, foreign object, or other faults are removed upon the irradiation with the laser light. This facilitates the scattering of the laser light inside the support substrate when the support substrate is irradiated. Consequently, it is possible to lessen influences of any flaw, foreign object, or other faults over the irradiation of the laser light. In this case, the surface treatment may be an etching treatment using an abrasive or a dissolution treatment, for example.

In any of the method of manufacturing the flexible device according to the first embodiment of the disclosure and the apparatus for manufacturing the flexible device according to the embodiment of the disclosure, the interface and its vicinity between the support substrate and the flexible substrate is irradiated obliquely with the laser light in the multi-directions, so that the support substrate is detached from the flexible substrate. This makes it possible to reduce or eliminate the risk of formation of a region unirradiated with the laser light which is attributed to a foreign object or a flaw on the support substrate. Consequently, it is possible to manufacture a flexible device at an improved yield rate.

In the method of manufacturing the flexible device according to the second embodiment of the disclosure, the second surface of the support substrate is brought into contact with the flowable member. In the method of manufacturing the flexible device according to the third embodiment of the disclosure, the second surface of the support substrate is subjected to the surface treatment. This makes it possible to lessen influences of any flaw, foreign object, or other faults over the irradiation of the laser light. Consequently, it is possible to reduce occurrence of disadvantages at the manufacturing step of detaching the support substrate from the flexible substrate, thereby manufacturing a flexible device at an improved yield rate.

It should be noted that the effects described above are not necessarily limitative, and the technology may achieve any other effects described herein.