A thin-film device may include a carrier, a release layer, a stacking structure, and a flexible substrate. The release layer may be overlaid on the carrier, and the stacking structure is overlaid on the release layer. The stacking structure may include a first protective layer and a second protective layer, wherein the refractive index of the first protective layer exceeds that of the second protective layer. The flexible substrate may be overlaid on the release layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is based on, and claims priority from, Taiwan Application Serial Number 102117838, filed on May 21, 2013, the disclosure of which is hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

The technical field relates to thin-film devices.

BACKGROUND

A conventional manufacturing method for a flexible display panel includes separating a flexible substrate from a hardness carrier. When the flexible substrate is separated from the hardness carrier, a high-energy light beam is emitted to the hardness carrier to degrade the release layer. The flexible substrate may easily be separated from the hardness carrier. However, a part of the high-energy light beam may pass through the release layer and damage the flexible substrate, decreasing the yield rate of the product.

In some thin-film or thin-film transistor (TFT) processes, a high-energy light beam is emitted on the thin-film layer. However, a part of the high-energy light beam may pass through the thin-film layer to the flexible substrate and do damage thereto. Thus, the following processes are influenced, and the yield rate of the product may be decreased.

SUMMARY

The present disclosure may decrease damage to the flexible substrate caused by high-energy light beams, or protect the release layer during the aforementioned processes.

The present disclosure may provide a thin-film device including a carrier, a release layer, a stacking structure, and a flexible substrate. The release layer may be overlaid on the carrier, and the stacking structure is overlaid on the release layer. The stacking structure may include a first protective layer and a second protective layer in contact with the first protective layer, wherein the refractive index of the first protective layer is different from the refractive index of the second protective layer. The flexible substrate may be overlaid on the stacking structure.

The present disclosure may provide a thin-film device comprising a carrier, a release layer, a plurality of stacking structures overlaid on each other, and a flexible substrate. The release layer is overlaid on the carrier, and the stacking structures are overlaid on the release layer. Each of the stacking structures may include a first protective layer and a second protective layer contact with the first protective layer, wherein the refractive index of the first protective layer is different from the refractive index of the second protective layer. The flexible substrate is overlaid on the stacking structures. The first protective layers and the second protective layer may be alternately overlaid on each other.

The stacking structure of the present disclosure may decrease the energy of the light beam passing through the flexible substrate, or it protects the release layer during the aforementioned processes, thus improving the yield rate of the product.

DETAILED DESCRIPTION

FIG. 1is a cross-sectional view of a thin-film device1according the first embodiment of the present disclosure. The thin-film device1includes a carrier10, a release layer (or a sacrificial layer)20, a first stacking structure30, a flexible substrate40, a second stacking structure50, and an electronic device60. In the embodiment, the carrier10, the release layer20, the first stacking structure30, the flexible substrate40, the second stacking structure50, and the electronic device60are overlaid in sequence along a stacking direction D1. In another embodiment, the overlaid sequence is not limited thereto.

The carrier10may be a hardness carrier, such as a glass or a wafer. The release layer20may include organic or inorganic materials, such as hydrogen-containing silicon oxide, silicon nitride or silicon film. The release layer20is overlaid on the carrier10. When the release layer20is exposed to a light beam L1, the adhesion force between the flexible substrate40and carrier10is decreased, and thus, the carrier10may be separated from the thin-film device1.

The first stacking structure30is overlaid on the release layer20, and it may be a flexible stacking structure. The first stacking structure30may be a transparent material, and it can reflect a light beam with a specific wavelength, such as a light beam with a wavelength of 308 nm. The first stacking structure30includes at least one first protective layer31and at least one second protective layer32. Both the first protective layer31and the second protective layer32may be flexible layers, and the first protective layer31is in contact with the second protective layer32. The number of protective layers is not limited thereto. In the embodiment, the first protective layer31is overlaid on the release layer20, and the second protective layer32is overlaid on the first protective layer31.

The ratio of the refractive index of the first protective layer31to the refractive index of the second protective layer32is greater than 1.05. The absolute value of the refractive index of the first protective layer31minus the refractive index of the release layer20is greater than the absolute value of the refractive index of the second protective layer32minus the refractive index of the release layer20. The thickness of the first protective layer31and of the second protective layer32may be from 20 nm to 350 nm, and the ratio of the thickness of the first protective layer31to that of the second protective layer32may be from 0.1 to 5.

In general, the ratio is greater, and the reflection of the light beam L1by the stacking structure is greater. Thus, the thickness and the refractive index of the first protective layer31and those of the second protective layer32may be adjusted according to the wavelength of the light beam to give the stacking structure a better reflectivity. In the embodiment, the refractive index of the first protective layer31is about 2.03, and the refractive index of the second protective layer32is about 1.49. The ratio of the refractive index of the first protective layer31to the refractive index of the second protective layer32is about 1.36. The thickness of the first protective layer31is about 45 nm, and the thickness of the second protective layer32is about 45 nm.

In general, if a protective layer has a greater thickness, the protective layer has a better reflectivity to a light beam with a longer wavelength. For example, a protective layer 35 nm thick has a better reflectivity to reflecting light beams with a wavelength of 250 nm, a protective layer 44 nm thick has a better reflectivity to light beams with a wavelength of 308 nm, and a protective layer 142 nm thick has a better reflectivity to light beams with a wavelength of 1000 nm.

In addition, in the direction in which the light beam L1is being transmitted, the refractive index of the protective layer (such as the first protective layer31inFIG. 1) that the light beam L1passes through first is greater, and the reflectivity of the protective layer to the light beam L1is better. Thus, in the embodiment, the refractive index of the first protective layer31is greater than the refractive index of the second protective layer32, but it is not be limited thereto.

The first protective layer31includes silicon nitride, silicon oxide, titanium oxide, niobium oxide, or combinations thereof. In the embodiment, the first protective layer31is made from Si3N4. The second protective layer32includes silicon nitride, silicon nitride, titanium oxide, or niobium oxide. In the embodiment, the second protective layer32is made from SiO2. The material of the protective layers may not be limited thereto when the refractive index of the material of the first protective layer31is not equal to (i.e. is greater than or less than) the refractive index of the material of the second protective layer32.

The flexible substrate40includes polymer. In the embodiment, the flexible substrate40is overlaid on the first stacking structure30. In other words, the first stacking structure30is located between the flexible substrate40and the release layer20. The second stacking structure50is overlaid on the flexible substrate40, and may be a flexible stacking structure. The second stacking structure50may be a transparent material, and reflects a light beam with a specific wavelength, such as a wavelength of 308 nm.

The second stacking structure50includes a third protective layer51and a fourth protective layer52. Since the characteristics of the third protective layer51and the fourth protective layer52are similar to the characteristics of the first protective layer31and the second protective layer32, a further detailed description will be omitted for brevity. In an embodiment, the refractive index, material, and thickness of the first protective layer31and those of the third protective layer51are the same, and the refractive index, material, and thickness of the second protective layer32and of the fourth protective layer52are the same.

The electronic device60includes electronic components such as resistors, capacitors, and/or inductors. The electronic device60may be a flexible display panel or a flexible semiconductor component, and the flexible display panel may be a flexible organic light-emitting diode (OLED) panel, or a liquid-crystal panel. The electronic device60is overlaid on the second stacking structure50.

In another embodiment, the structure as shown inFIG. 1may exclude the first stacking structure30or the second stacking structure50. For example, in an embodiment, the second stacking structure50is excluded, and the electronic device60is in contact with the flexible substrate40.

FIG. 2is a cross-sectional view of the electronic device60according to the first embodiment of the present disclosure. In the embodiment, the electronic device60may be a flexible OLED display panel including a buffer layer61, a thin-film transistor layer (TFT)62, an organic light-emitting diode (OLED) layer63, and a protective layer64. The buffer layer61, the thin-film transistor layer62, the organic light-emitting diode layer63, and the protective layer64may be overlaid in sequence along the stacking direction D1.

The thin-film transistor layer62may includes a plurality of transistors (not shown), and the organic light-emitting diode layer63may include a plurality of organic light-emitting diodes (not shown). In another embodiment, the electronic device60may be a flexible semiconductor component, and the thin-film transistor layer62may be a metal oxide semiconductor (MOS) layer. In another embodiment, the electronic device60may be a liquid-crystal panel, and the organic light-emitting diode layer63may be a liquid-crystal layer. However, since the electronic device60is a conventional art, a further detailed description will be omitted for brevity.

In another embodiment, the electronic device60may be excluded, or a part of the components in the electronic device60is excluded. The flexible substrate40may be a flexible display panel or a flexible semiconductor component, and the structure of the flexible substrate40may be similar to the structure of the electronic device60. The designs of the flexible substrate40and the electronic device60may refer to the described electronic device60.

As shown inFIG. 1, when a user wants to remove the carrier10from the thin-film device1, the light beam L1is emitted to the carrier10along the stacking direction D1and passes through the thin-film device1. The light beam L1may be a high-energy light beam, such as a laser or an ultraviolet light. In the embodiment, the light beam L1may be laser, and the wavelength of the light beam L1is from 200 nm to 750 nm. In this case, the wavelength is 308 nm.

When the light beam L1passes through the release layer20, the release layer20undergoes a chemical change, such as gasification or decomposition, due to the light beam L1. Thus, the adhesion force between the flexible substrate40(the first stacking structure30) and the carrier10is decreased, and the carrier10is removable to the flexible substrate40(the first stacking structure30).

After the light beam L1passes through the release layer20, a part of the light beam L1passes through the first stacking structure30. When the light beam L1passes through the first stacking structure30, the light beam L1is reflected, totally reflected, and/or refracted to the first protective layer31and the second protective layer32. Thus, a part of the light beam L1is blocked from emitting to the flexible substrate40. In the embodiment, the reflectivity of the first stacking structure30to the light beam L1is at least 50%, and thus, the degradation and the damage of the flexible substrate40due to the high-energy light beam L1is deceased, improving the yield rate of the product.

After the light beam L1passes through the first stacking structure30, a part of the light beam L1passes through the second stacking structure50. Similarly, when the light beam L1passes through the second stacking structure50, the light beam L1is reflected, totally reflected, or refracted on the third protective layer51and the fourth protective layer52. Thus, a part of the light beam L1is blocked from being emitted to the electronic device60.

In the embodiment, the reflectivity of the second stacking structure50to the light beam L1is at least 50%, and the energy of the light beam L1may be further decreased. Thus, some important components, such as the transistors and the organic light-emitting diodes, in the electronic device60are protected from the light beam with high energy, and the yield rate of the product is improved.

During manufacture of the thin-film transistor layer62, a light beam L2with high energy is emitted onto the electronic device60along the stacking direction D1. Since the reflectivity of the first stacking structure30or the second stacking structure50to the light beam L2are at least 50%, the release layer20and the flexible substrate40are protected from the light beam L2with high energy, and the yield rate of the product is improved.

In another embodiment, the first stacking structure30or the second stacking structure50is selective. The arrangement of the first stacking structure30and/or the second stacking structure50in the thin-film device1may be changed. Additional stacking structures may be included on the thin-film device1.

FIG. 3is a cross-sectional view of a first stacking structure30according to a second embodiment of the present disclosure.FIG. 4is a cross-sectional view of a second stacking structure50according to a second embodiment of the present disclosure. In the embodiment, there are a plurality of first stacking structures30overlaid on each other and a plurality of second stacking structures50overlaid on each other. Namely, there are at least two stacking structures overlaid on each other on the release layer20along the stacking direction D1.

In the embodiment, there are four first stacking structures30overlaid on each other and four second stacking structures50overlaid on each other. The bottom first protective layer31is in contact with the release layer20, and the top second protective layer32is in contact with the flexible substrate40. The bottom third protective layer51is in contact with the flexible substrate40, and the top fourth protective layer52is in contact with the electronic device60. The first protective layers31and the second protective layers32of all of the first stacking structures30are alternately overlaid on each other, and the third protective layers51and the fourth protective layers52of all of the second stacking structure50are alternately overlaid on each other. Namely, the protective layers with a higher refractive index and the protective layers with a lower refractive index are alternately overlaid on each other.

In the embodiment, the reflectivity of the first stacking structures30or the second stacking structures50to the light beam L1is from 85% to 95%. The degradation and the damage to the flexible substrate40and the electronic device60caused by the light beam L1is decreased due to the first stacking structures30and the second stacking structures50, and thus the yield rate of a product is improved.

In another embodiment, the reflectivity of the first stacking structures30or the two second stacking structures50to the light beam L1is from 50% to 60%. In another embodiment, the reflectivity of three first stacking structures30or three second stacking structures50to the light beam L1is from 70% to 80%. Thus, in general, when the first stacking structures30or the second stacking structures50are greater in number, the reflectivity of the first stacking structures30or the second stacking structures50to the light beam L1is greater.

The numbers of the first stacking structures30and the second stacking structures50are not limited thereto. The number of first stacking structures30and second stacking structures50may be different. For example, the number of first stacking structures30is one, and the number of second stacking structures50is three.

FIG. 5is a cross-sectional view of the first stacking structure30aaccording to a third embodiment of the present disclosure.FIG. 6is a cross-sectional view of the second stacking structure50aaccording to the third embodiment of the present disclosure. The differences between the third embodiment and the second embodiment are described as follows. The first stacking structure30amay further include a fifth protective layer33and a seventh protective layer34. The design of the fifth protective layer33and the seventh protective layer34may be similar to that of the first protective layer31and the second protective layer32, with regards to material and thickness. The thickness of each of the protective layers31,32,33and34may be different. In another case, at least two of the protective layers31,32,33and34may have the same thickness, such as the thickness of protective layers31and33are the same, and the thickness of protective layers32are34are the same.

The protective layers31,32,33and34may be arranged in sequence. Namely, the fifth protective layer33is overlaid on the second protective layer32, and the seventh protective layer34is overlaid on the fifth protective layer33, and the refractive index of two adjacent protective layers is different. For example, the refractive index of the fifth protective layer33and that of the second protective layer32are different; likewise the refractive index of the seventh protective layer34and the fifth protective layer33. The protective layers31,32,33and34may include different materials, or at least two of protective layers31,32,33and34include the same material. In other words, protective layers31,32,33and34each have a different refractive index, or at least two of the protective layers31,32,33and34may be the same.

In the embodiment, the refractive index of the first protective layer31is greater than the refractive index of the second protective layer32. The refractive index of the second protective layer32is smaller than the refractive index of the fifth protective layer33. The refractive index of the fifth protective layer33is greater than the refractive index of the seventh protective layer34. Thus, the protective layers having a greater refractive index and the protective layers having a lower refractive index are alternately overlaid on each other to provide a better refractive of to the light beam.

In another embodiment, the refractive index of the first protective layer31is smaller than the refractive index of the second protective layer32. The refractive index of the second protective layer32is greater than the refractive index of the fifth protective layer33. The refractive index of the fifth protective layer33is smaller than the refractive index of the seventh protective layer34.

The second stacking structure50afurther includes a sixth protective layer53and an eighth protective layer54. The characteristics, specifically in terms of refractive index, thickness and arrangement, of protective layers51,52,53and54are the same as the characteristics previously described for protective layers31,32,33and34. The refractive index of two adjacent protective layers may be different. For example, the refractive index of the sixth protective layer53and that of the fourth protective layer52are different, and the refractive index of the eighth protective layer54and that of the sixth protective layer53are different.

In the embodiment, the refractive index of the third protective layer51is greater than the refractive index of the fourth protective layer52. The refractive index of the fourth protective layer52is smaller than the refractive index of the sixth protective layer53. The refractive index of the sixth protective layer53is greater than the refractive index of the eighth protective layer54. Thus, the protective layers having a greater refractive index and the protective layers having a lower refractive index are alternately overlaid on each other.

As with the second embodiment illustrated inFIGS. 3 and 4, the third embodiment may include a plurality of first stacking structures30aoverlaid on each other, and a plurality of second stacking structures50aoverlaid on each other. A top fifth protective layer33or a top seventh protective layer34may be in contact with the flexible substrate40, and a top sixth protective layer53or a top eighth protective layer54may be in contact with the electronic device60. The first protective layers31, the second protective layers32, the fifth protective layers33and the seventh protective layers34are alternately overlaid on each other. The third protective layers51, the fourth protective layers52, the sixth protective layers53and the eighth protective layers54are alternately overlaid on each other.

The refractive index of protective layers is not limited thereto, since the protective layer having the greater refractive index and the protective layers having a lower refractive index are alternately overlaid on each other. In other words, the refractive index of one of the protective layers may be greater or smaller than two adjacent protective layers. The number of protective layers included in the first stacking structure30aor the second stacking structure50ais not limited thereto. The number of protective layers included in the first stacking structure30aand second stacking structure50amay be different. For example, the first stacking structure30aincludes two protective layers, and the second stacking structure50aincludes three protective layers.

The disclosed features may be combined, modified, or replaced in any suitable manner in one or more disclosed embodiments, but are not limited to any particular embodiments. For example, in the first embodiment, there are a plurality of first stacking structures30and50. Each of the first stacking structures30includes four protective layers, and each of the second stacking structures50includes three protective layers.

The stacking structure of the present disclosure decreases the energy of the light beam passing through the flexible substrate, or protects the release layer during processing. Thus, the yield rate of the product is improved.

The terms, such as “first” or “second”, in the specification are for the purpose of descriptive clarity only, but are not relative to the claims or meant to limit the scope of the claims. In addition, terms such as “first feature” and “second feature” do not indicate the same or different features.