# Patent

## Title
Methods for fabricating an organic electro-luminescence device

## Abstract

A method for fabricating an organic electro-luminescence device, comprising: forming a first conductive layer comprising a first electrode and a contact pattern on a substrate; foil ling a first mask on the first conductive layer, the first mask comprising an opening for exposing a portion of the first electrode and a portion of the contact pattern; forming a patterned organic functional layer by shielding of a second mask, the patterned organic functional layer covering the first mask and the first electrode exposed by the first mask, and the second mask being disposed over the first mask to shield the portion of the contact pattern exposed by the opening; forming a second conductive layer and patterning the second conductive layer by removing the first mask and a portion of the second conductive layer on the first mask to form a second electrode electrically connected to the contact pattern.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the priority benefits of U.S. provisional application Ser. No. 62/140,474, filed on Mar. 31, 2015. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.


BACKGROUND
Technical Field
The present disclosure generally relates to a roll-to-roll process, in particular, to a method for fabricating an organic electro-luminescence device.
Description of Related Art
Organic electro-luminescent devices having high quantum efficiency and low power consumption are widely utilized in display and illumination fields. Since organic electro-luminescent devices are advantaged in light-weight and nice color rendering, organic electro-luminescent devices are considered as a mainstream of next generation displays and illumination devices. Currently, fabrication cost of organic electro-luminescent devices cannot be reduced easily, and different roll-to-roll processes and apparatuses designed for mass production are proposed accordingly. However, the aforesaid roll-to-roll processes for fabricating organic electro-luminescence devices suffers serious alignment issue (i.e., mis-alignment between stacked layers of the fabricated organic electro-luminescence devices occurs) which causes low yield rate. Accordingly, solutions for resolving the alignment issue during the roll-to roll processes are required.
SUMMARY
Accordingly, the present disclosure is directed to a method for fabricating an organic electro-luminescence device.
A method for fabricating an organic electro-luminescence device, comprising: forming a first conductive layer on a substrate, the first conductive layer comprising a first electrode and a contact pattern electrically insulated from the first electrode; forming a first mask on the first conductive layer, the first mask comprising an opening for exposing a portion of the first electrode and a portion of the contact pattern; forming a patterned organic functional layer by shielding of a second mask, the patterned organic functional layer covering the first mask and the first electrode exposed by the first mask, and the second mask being disposed over the first mask to shield the portion of the contact pattern exposed by the opening; removing the second mask after forming the patterned organic functional layer; forming a second conductive layer over the patterned organic functional layer, the first mask and the contact pattern exposed by the opening; and patterning the second conductive layer by removing the first mask and a portion of the second conductive layer on the first mask to form a second electrode electrically connected to the contact pattern.
A method for fabricating an organic electro-luminescence device, comprising: forming a first conductive layer on a substrate, the first conductive layer comprising a first electrode and a contact pattern electrically insulated from the first electrode; forming a first mask over the first conductive layer, the first mask comprising a first opening for exposing a portion of the first electrode and a portion of the contact pattern; forming a second mask on the first mask, the second mask comprising a second opening, the second mask shielding the contact pattern exposed by the first opening and the second opening exposing a portion of the first electrode; forming a patterned organic functional layer on the first electrode by shielding of the second mask; removing the second mask after forming the patterned organic functional layer; forming a second conductive layer over the patterned organic functional layer, the first mask and the contact pattern; and patterning the second conductive layer by removing the first mask and a portion of the second conductive layer on the first mask to form a second electrode electrically connected to the contact pattern.



BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
FIG. 1A through FIG. 1F schematically illustrate a method for fabricating an organic electro-luminescence device in accordance with a first embodiment.
FIG. 2A through FIG. 2F are top views or bottom views of the method for fabricating an organic electro-luminescence device in accordance with the first embodiment.
FIG. 3A through FIG. 3F are cross-sectional views along the cross-section IT in FIG. 2A through FIG. 2F.
FIG. 4A through FIG. 4I schematically illustrate a method for fabricating an organic electro-luminescence device in accordance with a second embodiment.
FIG. 5A through FIG. 5I are top views or bottom views of the method for fabricating an organic electro-luminescence device in accordance with the second embodiment.
FIG. 6A through FIG. 6I are cross-sectional views along the cross-section I-I′ in FIG. 5A through FIG. 5I.



DESCRIPTION OF THE EMBODIMENTS
Reference will now be made in detail to the present preferred embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
First Embodiment
FIG. 1A through FIG. 1F schematically illustrate a method for fabricating an organic electro-luminescence device in accordance with a first embodiment. FIG. 2A through FIG. 2F are top views or bottom views of the method for fabricating an organic electro-luminescence device in accordance with the first embodiment. FIG. 3A through FIG. 3F are cross-sectional views along the cross-section IT in FIG. 2A through FIG. 2F.
Referring to FIG. 1A, FIG. 2A and FIG. 3A, a roll-to-roll apparatus including a plurality of rollers R are provided. The rollers R are capable of conveying a substrate 100 along a transmission direction D1. In this embodiment, the substrate 100 is provided with a first conductive layer 110 formed thereon. The substrate 100 is an ultra-thin (e.g., less than 100 micro-meter) and flexible glass substrate. However, the material of the substrate 100 is not limited thereto. The first conductive layer 110 comprises a first electrode 112 and at least one contact pattern 114 electrically insulated from the first electrode 112. As shown in FIG. 2A and FIG. 3A, in this embodiment, two contact patterns 114 are formed at two opposite sides of the first electrode 112. It is noted that the shape and the number of the contact patterns 114 are not limited in this embodiment.
For instance, a method for fabricating the first electrode 112 and the contact patterns 114 may comprises the following steps. First, a transparent conductive oxide (TCO) layer is formed over the substrate 100 through sputtering, for example. Then, the TCO layer is patterned through laser irradiation provided by a laser light source L, for example. After the TCO layer is patterned, the first electrode 112 may comprise two notches and the contact patterns 114 are located in the notches. As shown in FIG. 2A and FIG. 3A, after the TCO layer is patterned, a gap G exists between the first electrode 112 and each contact pattern 114 such that the contact patterns 114 are capable of being electrically insulated from the first electrode 112.
Referring to FIG. 1B, FIG. 2B and FIG. 3B, after the first electrode 112 and the contact patterns 114 are formed over the substrate 100, a first mask 120 is formed on the first conductive layer 110. The first mask 120 comprises an opening 122 for exposing a portion of the first electrode 112 and a portion of the contact patterns 114. The gap G between the first electrode 112 and each contact pattern 114 is partially exposed by the opening 122 of the first mask 120. As shown in FIG. 2B and FIG. 3B, a portion of the gap G between the first electrode 112 and each contact pattern 114 is filled and covered by the first mask 120. Furthermore, a peripheral area of the first electrode 112 and a portion of each contact pattern 114 are covered by the first mask 120. In other words, a central area of the first electrode 112 is exposed by the opening 122 of the first mask 120.
Referring to FIG. 1C, FIG. 2C and FIG. 3C, a second mask 130 is provided over the first mask 120 so as to shield the portion of each contact pattern 114 exposed by the opening 122 of the first mask 120. In other words, the contact patterns 114 and the gaps G are covered and shielded by the second mask 130. Beside, portions of the first mask 120 are uncovered and exposed by the second mask 130. As shown in FIG. 2B, the first mask 120 is a frame mask having the opening 122, the second mask 130 comprises at least one pair of shielding strips 132, and a lengthwise direction of the shielding strips 132 is parallel to the transmission direction D1. In this embodiment, the second mask 130 is provided over and in contact with the first mask 120, and the second mask 130 is not in contact with the first conductive layer 110, for example.
After the second mask 130 is provided, an evaporation process is, for example, performed to form a patterned organic functional layer 140 by shielding of a second mask 130. The patterned organic functional layer 140 covers the portions of the first mask 120 that are exposed by the second mask 130 and the central area of the first electrode 112 that is exposed by the opening 122 of the first mask 120.
As shown in FIG. 2C, since the second mask 130 is not in contact with the first conductive layer 110, the evaporated patterned organic functional layer 140 may cover sidewalls of the first electrode 112 that are exposed by the opening 122 of the first mask 120. In other words, the patterned organic functional layer 140 may extend into the gaps G so as to encapsulate sidewalls and a top surface of the first electrode 112 that are exposed by the opening 122 of the first mask 120.
Referring to FIG. 1D, FIG. 2D and FIG. 3D, after forming the patterned organic functional layer 140, the substrate 100 comprising the first conductive layer 110, the first mask 120 and the patterned organic functional layer 140 formed thereon is conveyed along the transmission direction D1 to ensure that the second mask 130 is removed. Then, a second conductive layer 150 is formed over the patterned organic functional layer 140, the first mask 120 and the contact pattern 114 exposed by the opening 122 of the first mask 120. In this embodiment, the second conductive layer 150 is formed by evaporation process.
As shown in FIG. 3D, first electrode 112 and the second conductive layer 150 are spaced apart by the patterned organic functional layer 140, since the patterned organic functional layer 140 extends into the gaps G so as to encapsulate sidewalls and a top surface of the first electrode 112 that are exposed by the opening 122 of the first mask 120. In other words, the patterned organic functional layer 140 may prevents short circuit between the first electrode 112 and the second conductive layer 150.
Referring to FIG. 1E, FIG. 2E and FIG. 3E, after the second conductive layer 150 is formed, the second conductive layer 150 is patterned by removing the first mask 120 and a portion of the second conductive layer 150 on the first mask 120 so as to form a second electrode 152. The second electrode 152 is electrically connected to the contact patterns 114 and is spaced apart from the first electrode 112 by the patterned organic functional layer 140. After the second electrode 152 is formed, fabrication of the organic electro-luminescence device of this embodiment is about accomplished.
Referring to FIG. 1F, FIG. 2F and FIG. 3F, in order to enhance reliability of the organic electro-luminescence device, an encapsulation 160 may be formed to encapsulate the second electrode 152. In some embodiments, the encapsulation 160 may further encapsulate a portion of the contact patterns 114.
It is noted that deviation of the substrate 100 along a direction D2 perpendicular to the transmission direction D1 often occurs when the substrate 100 is conveyed along the transmission direction D1. Such deviation of the substrate 100 may cause mis-alignment between stacked layers of the organic electro-luminescence devices. Since first mask 120 is formed over the substrate 100, the first mask 120 can minimize the above-mentioned mis-alignment issue in the directions D1 and D2.
Second Embodiment
FIG. 4A through FIG. 4I schematically illustrate a method for fabricating an organic electro-luminescence device in accordance with a second embodiment. FIG. 5A through FIG. 5I are top views or bottom views of the method for fabricating an organic electro-luminescence device in accordance with the second embodiment. FIG. 6A through FIG. 6I are cross-sectional views along the cross-section I-I′ in FIG. 5A through FIG. 5I.
Referring to FIG. 4A, FIG. 5A and FIG. 6A, a roll-to-roll apparatus including a plurality of rollers R are provided. The rollers R are capable of conveying a substrate 200 along a transmission direction D1. In this embodiment, the substrate 200 is provided with a first conductive layer 210 formed thereon. The substrate 200 is an ultra-thin (e.g., less than 100 micro-meter) and flexible glass substrate. However, the material of the substrate 200 is not limited thereto. The first conductive layer 210 comprises a first electrode 212 and at least one contact pattern 214 electrically insulated from the first electrode 212. As shown in FIG. 5A and FIG. 6A, in this embodiment, two contact patterns 214 are formed at two opposite sides of the first electrode 212. It is noted that the shape and the number of the contact patterns 214 are not limited in this embodiment.
For instance, a method for fabricating the first electrode 212 and the contact patterns 214 may comprises the following steps. First, a transparent conductive oxide (TCO) layer is formed over the substrate 200 through sputtering, for example. Then, the TCO layer is patterned through laser irradiation provided by a laser light source L, for example. After the TCO layer is patterned, the first electrode 212 may comprise two notches and the contact patterns 214 are located in the notches. As shown in FIG. 2A and FIG. 3A, after the TCO layer is patterned, a gap G exists between the first electrode 212 and each contact pattern 214 such that the contact patterns 214 are capable of being electrically insulated from the first electrode 212.
Referring to FIG. 4B, FIG. 5B and FIG. 6B, after the first electrode 212 and the contact patterns 214 are formed over the substrate 200, a mask 220 for defining sequentially formed encapsulation (i.e., a third mask 220) is formed on the first conductive layer 210. The third mask 220 comprises a third opening 222 for exposing a portion of the first electrode 212 and a portion of the contact patterns 214. The gap G between the first electrode 212 and each contact pattern 214 is partially exposed by the third opening 222 of the third mask 220. As shown in FIG. 5B and FIG. 6B, a portion of the gap G between the first electrode 212 and each contact pattern 214 is filled and covered by the third mask 220. Furthermore, a peripheral area of the first electrode 212 and a portion of each contact pattern 214 are covered by the third mask 220. In other words, a central area of the first electrode 212 is exposed by the third opening 222 of the third mask 220. It is noted that formation of the third mask 220 is optional in this embodiment.
Referring to FIG. 4C, FIG. 5C and FIG. 6C, a first mask 230 is then formed over the first conductive layer 210. In this embodiment, the first mask 230 is formed on the third mask 220. The first mask 230 comprises a first opening 232 for exposing a portion of the first electrode 212 and a portion of the contact patterns 214, wherein the first opening 232 of the first mask 230 is smaller than the third opening 222 of the third mask 220. The gap G between the first electrode 212 and each contact pattern 214 is partially exposed by the third opening 222 of the third mask 220.
It should be noted that formation of the third mask 220 is optional in this embodiment. When the formation of the third mask 220 is omitted (i.e., the first mask 230 is formed on and in contact with the first conductive layer 210), a portion of the gap G between the first electrode 212 and each contact pattern 214 is filled and covered by the first mask 230. Furthermore, a peripheral area of the first electrode 212 and a portion of each contact pattern 214 are covered by the first mask 230. In other words, a central area of the first electrode 212 is exposed by the first opening 232 of the first mask 230.
Referring to FIG. 4D, FIG. 5D and FIG. 6D, a second mask 240 is formed on the first mask 230, wherein the second mask 240 comprises a second opening 242, the second mask 240 shields the contact patterns 214 exposed by the first opening 232 of the first mask 230, and a portion of the first electrode 212 is exposed by the second opening 242. As shown in FIG. 5D and FIG. 6D, the second opening 242 of the second mask 240 is smaller than the first opening 232 of the first mask 230. In this embodiment, the first mask 230, the second mask 240 and the third mask 220 are frame masks having openings in different sizes. In this embodiment, the second mask 240 is provided over and in contact with the first mask 230, and the second mask 240 is not in contact with the first conductive layer 210, for example.
Referring to FIG. 4E, FIG. 5E and FIG. 6E, after the second mask 240 is provided, an evaporation process is, for example, performed to form a patterned organic functional layer 250 by shielding of the second mask 240. The evaporated patterned organic functional layer 250 covers the central area of the first electrode 212 that is exposed by the second opening 242 of the second mask 240 and the first opening 232 of the first mask 230.
As shown in FIG. 5E, since the second mask 240 is not in contact with the first conductive layer 210, the evaporated patterned organic functional layer 250 may cover sidewalls of the first electrode 212 that are exposed by the first opening 232, the second opening 242 and the third opening 222. In other words, the patterned organic functional layer 250 may extend into the gaps G so as to encapsulate sidewalls and a top surface of the first electrode 212.
Referring to FIG. 4F, FIG. 5F and FIG. 6F, after forming the patterned organic functional layer 250, the second mask 240 is removed. In order to remove the second mask 240, the adhesion between the first mask 230 and the second mask 240 is required to be smaller than the adhesion between the first mask 230 and the third mask 220. Then, a second conductive layer 260 is formed over the patterned organic functional layer 250, the first mask 230 and a portion of the contact pattern 214. In this embodiment, the second conductive layer 260 is formed by evaporation process, for example.
As shown in FIG. 6F, since the patterned organic functional layer 250 extends into the gaps G so as to encapsulate sidewalls and a top surface of the first electrode 212 which are exposed by the opening 232 of the first mask 230, the first electrode 212 and the second conductive layer 260 are spaced apart by the patterned organic functional layer 250. In other words, the patterned organic functional layer 250 may prevents short circuit between the first electrode 212 and the second conductive layer 260.
Referring to FIG. 4G, FIG. 5G and FIG. 6G, after forming the second conductive layer 260, the second conductive layer 260 is patterned by removing the first mask 230 and a portion of the second conductive layer 260 on the first mask 230 so as to form a second electrode 262. In order to remove the first mask 230, the adhesion between the first mask 230 and the third mask 220 is required to be smaller than the adhesion between the third mask 220 and the first conductive layer 212. The second electrode 262 is electrically connected to the contact patterns 214 and is spaced apart from the first electrode 212 by the patterned organic functional layer 250. After the second electrode 262 is formed, fabrication of the organic electro-luminescence device of this embodiment is about accomplished.
Referring to FIGS. 4H-4I, FIGS. 5H-5I and FIGS. 6H-6I, in order to enhance reliability of the organic electro-luminescence device, an encapsulation material layer 270 may be formed to cover the third mask 220, a portion area of the contact patterns 214 and the second electrode 262. Then, the encapsulation material layer 270 is patterned by removing the third mask 220 and a portion of the encapsulation material layer 270 on the third mask 220 so as to form an encapsulation 272.
In the aforesaid embodiments, it is noted that deviation of the substrate (100, 200) along a direction D2 perpendicular to the transmission direction D1 often occurs when the substrate (100, 200) is conveyed along the transmission direction D1. Such deviation of the substrate (100, 200) may cause mis-alignment between stacked layers of the organic electro-luminescence devices. Since the first mask (120, 230), the second mask (130, 240) and the third mask 220 are formed over the substrate (100, 200), the aforesaid first mask 230, the second mask (130, 240) and the third mask 220 can minimize the above-mentioned mis-alignment issue in the directions D1 and D2.
In this disclosure, the mask formed on the substrate can effectively resolve alignment issue of stacked layers in the organic electro-luminescence devices, and thus enhance yield rate of mass production of the organic electro-luminescence devices.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fall within the scope of the following claims and their equivalents.

## Claims

1. A method for fabricating an organic electro-luminescence device, comprising:
forming a first conductive layer on a substrate, the first conductive layer comprising a first electrode and a contact pattern electrically insulated from the first electrode;
forming a first mask on the first conductive layer, the first mask comprising an opening for exposing a portion of the first electrode and a portion of the contact pattern to an environment where the substrate and the first mask are placed;
forming a patterned organic functional layer by shielding of a second mask, the patterned organic functional layer covering the first mask and the first electrode exposed by the first mask, and the second mask being disposed over the first mask to shield the portion of the contact pattern exposed by the opening;
removing the second mask after forming the patterned organic functional layer;
forming a second conductive layer over the patterned organic functional layer, the first mask and the contact pattern exposed by the opening; and
patterning the second conductive layer by removing the first mask and a portion of the second conductive layer on the first mask to form a second electrode electrically connected to the contact pattern.

2. The method according to claim 1, wherein the first electrode comprises a notch and the contact pattern is located in the notch.

3. The method according to claim 2, wherein a gap is between the first electrode and the contact pattern.

4. The method according to claim 3, wherein the gap is partially exposed by the opening of the first mask and is shielded by the second mask.

5. The method according to claim 1, wherein the first electrode and the second electrode are spaced apart by the patterned organic functional layer.

6. The method according to claim 1, wherein the substrate is conveyed along a transmission direction to form the first electrode, the contact pattern, the first mask, the patterned organic functional layer and the second electrode on the substrate.

7. The method according to claim 6, wherein the first mask or the second mask is a frame mask.

8. The method according to claim 6, wherein the second mask comprises at least one pair of shielding strips, and a lengthwise direction of the shielding strips is parallel to the transmission direction.

9. The method according to claim 1 further comprising:
forming an encapsulation to encapsulate the second electrode.

10. A method for fabricating an organic electro-luminescence device, comprising:
forming a first conductive layer on a substrate, the first conductive layer comprising a first electrode and a contact pattern electrically insulated from the first electrode;
forming a first mask over the first conductive layer, the first mask comprising a first opening for exposing a portion of the first electrode and a portion of the contact pattern to an environment where the substrate and the first mask are placed;
forming a second mask on the first mask, the second mask comprising a second opening, the second mask shielding the contact pattern exposed by the first opening, and the second opening exposing a portion of the first electrode;
forming a patterned organic functional layer on the first electrode by shielding of the second mask;
removing the second mask after forming the patterned organic functional layer;
forming a second conductive layer over the patterned organic functional layer, the first mask and the contact pattern; and
patterning the second conductive layer by removing the first mask and a portion of the second conductive layer on the first mask to form a second electrode electrically connected to the contact pattern.

11. The method according to claim 10, wherein the first electrode comprises a notch and the contact pattern is located in the notch.

12. The method according to claim 11, wherein a gap is between the first electrode and the contact pattern.

13. The method according to claim 12, wherein the gap is partially exposed by the first opening of the first mask.

14. The method according to claim 10, wherein the first electrode and the second electrode are spaced apart by the patterned organic functional layer.

15. The method according to claim 10, wherein the substrate is conveyed along a transmission direction to form the first electrode, the contact pattern, the first mask, the second mask, the patterned organic functional layer and the second electrode on the substrate.

16. The method according to claim 15, wherein the first mask or the second mask is a frame mask.

17. The method according to claim 15, wherein the second mask at least one pair of shielding strips, and a lengthwise direction of the shielding strips is parallel to the transmission direction.

18. The method according to claim 10 further comprising:
forming a third mask on the first conductive layer before the first mask is formed, the third mask comprising a third opening for exposing a portion of the first electrode and a portion of the contact pattern;
forming an encapsulation material layer over the second electrode and the third mask; and
patterning the encapsulation material layer by removing the third mask and a portion of the encapsulation material layer on the third mask to form an encapsulation.

19. The method according to claim 18, wherein an adhesion between the first mask and the second mask is smaller than an adhesion between the first mask and the third mask.

20. The method according to claim 18, wherein the adhesion between the first mask and the third mask is smaller than an adhesion between the third mask and the first conductive layer.