US20150022742A1

US20150022742A1 - Pattern substrate and touch panel using the same

Info

Publication number: US20150022742A1
Application number: US14/506,406
Authority: US
Inventors: Jun Lee; Kyoung Jong Yoo; Young Jae Lee; Jin Su Kim
Original assignee: LG Innotek Co Ltd
Current assignee: LG Innotek Co Ltd
Priority date: 2011-12-19
Filing date: 2014-10-03
Publication date: 2015-01-22
Also published as: KR20130070076A; WO2013094918A1; EP2795666A4; US9536819B2; CN103503114A; US20140272316A1; EP2795666B1; EP2795666A1; CN103503114B; JP6257522B2; JP2015503244A; KR101856231B1; TW201340172A

Abstract

A touchscreen display device includes a display module and an electrically conductive and light transmissive layer provided over the display module to allow detection of touch input. The electrically conductive and light transmissive layer includes a transparent substrate and a transparent layer provided over the transparent substrate. The transparent layer has first and second surfaces, which are opposing surfaces, and the first surface faces the transparent substrate. The second surface includes a plurality of protrusions extending in different directions such that the plurality of first protrusions intersect to form recess regions on the second surface. The recess regions include a plurality of second protrusions, and the second protrusions have a height and a width less than the first protrusions. At least one metallic wiring layer is formed on the plurality of first protrusions including at locations where the first protrusions intersect.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application is a Continuation-In-Part application of U.S. application Ser. No. 14/358,701 having a 371(c) filing date of May 15, 2014, which is a U.S. National Stage application of International Application No. PCT/KR2012/010739 filed Dec. 11, 2012, claiming priority to Korean Application No. 10-2011-0137217 filed on Dec. 19, 2011, whose entire disclosures are incorporated herein by reference.

BACKGROUND

1. Field
The present disclosure relates to a transparent substrate having a nano pattern for use to a touchscreen of a display module.
2. Related Art
When manufacturing a semiconductor device, a word line, it is necessarily required to implement various fine patterns such as a digit line, a contact and the like. A lithograph technology has been generally applied to form these fine patterns.
A contact lithograph method which has been traditionally and widely used enables the pattern to be formed throughout a wide area. However, due to a limit of the diffraction of light, it was problematic that a pitch of the fine pattern which can be formed is limited (1˜2 μm).
Accordingly, to solve this problem, a stepper method, a scanner method, a holographic lithography method and the like were developed. However, these methods need complicated and sophisticated equipment and incur high expenses. Further, the methods have a limit in view of the fact that an area which can form a pattern is limited. That is, the conventional lithograph method is basically limited to implement nonoscale fine patterns due to the problems such as a limitation of equipment or a process property. More specifically, upon the use of the conventional lithography technology, it would be difficult to implement nanoscale patterns which are uniformly formed throughout a large area of more than 8 inch.
According to the aforesaid problems, a method of forming a porous metal thin film using a porous template made of a metal material as disclosed in Korean Laid-Open Patent Publication No. 2011-0024892, and forming nano patterns using the porous metal thin film as a catalyst was suggested. The method was problematic in that because the porous template should be prepared in advance, it is inconvenient to use the method, and because a catalyst growth method is used, nano patterns can be formed at only desired regions. Moreover, it was problematic that the nano patterns cannot be formed on a transparent substrate.
The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments will be described in detail with reference to the following drawings in which like reference numerals refer to like elements, wherein:

FIG. 1 and FIG. 2 are flow charts showing the order of a method of manufacturing a transparent substrate having a nano pattern according to the present disclosure.

FIG. 3 through FIG. 9 are the exemplary views of processes illustrating roughly the manufacturing processes of a transparent substrate having a nano pattern according to the present disclosure.

FIG. 10 illustrates a touchscreen comprising the transparent substrate having a nano pattern of the present disclosure.

FIGS. 11A-11C illustrate the arrangement of the transparent substrate as a touch screen in various display module configurations.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 and FIG. 2 are flow charts showing the order of a method of manufacturing a transparent substrate having a nano pattern according to the present disclosure. A method of manufacturing a transparent substrate having a nano pattern according to the present disclosure may include: forming a resin layer made of a transparent material on a transparent substrate (S1); forming at least one or more unit pattern parts, which are composed of a first and a second pattern areas in which a plurality of grid patterns are formed, and a protrusion pattern formed between the first pattern area and the second pattern area, on the resin layer (S3); and forming a nanoscale metal layer on the protrusion pattern (S5).
A material of the transparent substrate in used in step S1 may be glass, quartz, a polymer made of a transparent material, for example, publicly known polymer materials such as PET (polyethylene terephthalate), PC (polycarbonate), PI (polyimide). In addition to this, various flexible substrates may be used. The material is not limited.
After the transparent substrate is prepared, a resin layer is formed by applying a resin made of a transparent material to the transparent substrate. At this time, the resin may use a thermosetting polymer or a photo curable polymer. Meanwhile, to improve a bonding ability between the resin layer and the transparent substrate, the resin layer may be also formed by coating the transparent substrate with an adhesive before applying the resin, and thereafter applying the resin to the transparent substrate.
After step S1, at least one or more unit pattern parts, which are composed of a first pattern area and a second pattern area in which a plurality of grid patterns are formed, respectively, and a protrusion pattern formed between the first pattern area and the second pattern area, is formed on the resin layer (S3). Specially, step S3 may be performed as described below.
First, a master mold is produced (S31), the master mold having at least one or more unit mold pattern parts, which are composed of the first mold pattern area and the second mold pattern area in which a plurality of grid mold patterns are formed respectively, between the plurality of grid mold patterns there are formed with recesses, and a concave mold pattern formed between the first mold pattern area and the second mold pattern area.
The plurality of nanoscale grid mold patterns are first formed on an original material of the master mold using a space lithography process, for example, “a method of manufacturing a nanoscale pattern having a large area” as described in Korean patent application No. 10-2010-0129255. The master mold of the present disclosure may be produced by forming a concave mold pattern to divide a first mold pattern area and a second mold pattern area and forming one or more unit mold pattern parts. At this time, specifically, the formation method of the concave mold pattern may be performed by an electron-beam lithography process. However, the present disclosure is not limited to this.
Meanwhile, a width (A) of a recess between the gird mold patterns of the first mold pattern area or the second mold pattern area may be formed in a range of 50 to 100 nm. A width (B) of concave or squared recess mold pattern may be formed in a range of 200 to 1000 nm. The width (C) of the protrusions in the first mold pattern area or the second mold pattern area may be in a range of 50 to 100 nm. The master mold produced by this method is reusable until it is damaged. Furthermore, the master mold can continue to use at an imprinting process, causing economical advantages such as the reduction of a raw material charge and a production cost.
Then, the master mold produced in step S31 is arranged in an upper part of the resin layer, and one or more unit pattern parts corresponding to one or more unit mold pattern parts are formed on the resin layer through an imprinting process for pressurizing the resin layer (S33). Here, the unit pattern parts mean a structure including the first pattern area corresponding to the first mold pattern area, the second pattern area corresponding to the second mold pattern area, and the protrusion pattern unit corresponding to the concave mold pattern. The plurality of grid patterns corresponding to recesses between the plurality of grid mold patterns are provided in the first pattern area and the second pattern.
A process of hardening the resin layer is performed (S35). At this time, in a case where the resin layer is made of a thermosetting polymer, the resin layer is hardened by applying heat thereto. In a case where the resin layer is a photo curable polymer, the resin layer is hardened by irradiating ultraviolet rays thereto. Thereafter, step S3 of the present disclosure may be conducted by releasing the master mold from the resin layer (S37).
Then, in step S5, the nanoscale metal layer is formed on the protrusion pattern of the resin layer. A metallic layer is first deposited on the grid patterns and the protrusion pattern. At this time, the deposited metal may use any one of Al, Cr, Ag, Cu, Ni, Co and Mo or an alloy thereof. However, the present disclosure should not be limited to this, and other metals may be appropriately used as need. The deposition method of the metal may be at least one method of a sputtering method, a chemical vapor deposition method, and an evaporation method. However, this is only one example. In addition to the methods, all deposition methods, which have been developed and commercialized or can be embodied according to future technical development, may be used.
Meanwhile, a height of depositing the metal may be formed to be more than a pitch value (See “P” of FIG. 7) of the grid patterns, and the metal may be uniformly deposited on each grid pattern and the protrusion pattern. The pitch value being a distance between a center of a protrusion to a center of an adjacent protrusion. This pitch value may be in a range of 100 to 200 nm. This is intended to easily remove the metal formed on the grid patterns at an etching process later.
After the metal is deposited, a wet etching process is performed thereon, so isotropic etching is performed at exposed three sides of the metal. Thus, the metal deposited on the grid patterns is etched, or a part bonded to the grid patterns is peeled off. Consequently, the metal deposited on the grid patterns is removed, and the metal on the protrusion pattern remain so as to form the metal layer. The reason why the metal deposited on the grid patterns is removed and the metal on the protrusion pattern remains so as to form the metal layer is because a contact area between the metal deposited on the grid patterns and an etching solution used during the wet etching process is more than the metal deposited on the protrusion pattern. Thus, the transparent substrate having the nano pattern of the present disclosure, including the nano pattern and nanoscale metal layer may be produced.
As the wet etching process is used, the process can be performed even at room temperature, and as the manufacturing process of the master mold can be performed separately, flexible processes can be secured. Furthermore, the master mold is available until it is damaged, causing the reduction of a raw material charge and a production cost.
The nano patterns may be uniformly implemented throughout the wide area of the transparent substrate, and the nanoscale metal layer may be also uniformly formed on the transparent substrate. Thus, it is advantageous that the transparent substrate having electrical conductivity equal to ITO can be provided at a low cost, and an Ag mesh which is emerging as a substitute for the ITO can be produced as a nanoscale pattern. Accordingly, the transparent substrate with nano patterns can be utilized in various fields such as a touch panel, a liquid crystal device, a solar cell and the like.
FIG. 3 through FIG. 9 are the exemplary views of processes illustrating roughly the manufacturing processes of a transparent substrate having a nano pattern according to the present disclosure. As illustrated in FIG. 3, a structure 10 a in which the plurality of nanoscale grid mold patterns 11 on an upper surface thereof are formed is produced. At this time, the space lithograph process may be used as a method of forming the grid mold pattern 11. This is the same as described in the explanation of FIG. 2.
Thereafter, as illustrated in FIG. 4 and FIG. 5, a master mold 10 having at least one or more unit mold pattern parts 10 b are produced by patterning the structure 10 a as illustrated in FIG. 3 through an electron-beam lithography process. At this time, the unit mold pattern parts 10 b are composed of a first mold pattern area 13, a second mold pattern area 17, and a concave or squared recessed mold pattern 15 formed between the first mold pattern area 13 and the second mold pattern area 17. The mold pattern area 13 and the second mold pattern area 17 have a plurality of grid mold patterns 11 with recesses between them. The grid mold pattern 11 is shown as a series of protrusions, e.g., squared protrusions, but other shaped protrusion patterns are possible.
Here, a width (B) of the concave mold pattern 15 is formed to be wider than a width (A) of the recess between the patterns of the first mold pattern area 13 or a width of the recess between the patterns of the second mold pattern area 17. More specifically, the width (B) of the concave mold pattern 15 may be formed in the range of 200 to 1000 nm. The width (A) of the recess between the patterns of the first mold pattern area 13 or the width (A) of the recess between the patterns of the second mold pattern area 17 may be formed in the range of 50 to 100 nm. The width (C) of the protrusions may be in the range of 50 to 100 nm. However, the present disclosure is not limited to this. Also, a depressed depth of the concave mold pattern 15 may be formed to be deeper than a height of the grid mold pattern 11. In an embodiment, the height of the pattern 15 is greater than the height of the pattern 11 and the height of the pattern 11 is less than the height of the pattern 15.
Then, as illustrated in FIG. 6, the imprinting process for pressurizing the resin layer 30 formed on the transparent substrate 20 using the master mold (10 of FIG. 5), in which one or more unit mold pattern parts 10 b are formed, is conducted. The detailed explanation on the transparent substrate 20 and the resin layer 30 is the same as described in the explanation of FIG. 1 and FIG. 2, and thus is omitted. The master mold (10 of FIG. 5) is released from the resin layer 30 after applying a photo curing process or a heat curing process, as illustrated in FIG. 7, so that one or more unit pattern parts 30 b corresponding to the unit mold pattern parts (10 b of FIG. 5 and FIG. 6) may be formed on the resin layer 30. Here, the unit pattern parts 30 b are composed of the first pattern area 33, the second pattern area 37, and the protrusion pattern 35 formed between the first pattern area 33 and the second pattern area 37. The first pattern area 33, and the second pattern area 37 have the plurality of grid patterns 31, and the protrusion 35 have shapes and patterns that complements the shapes and patterns recesses of the first mold pattern area 13, of the second mold pattern area 17, and the recess 15.
Due to the imprint of the master mold on the resin layer 30, the dimensions are substantially the same in a complementary manner. A width (E) of the protrusion pattern 35 may be formed to be wider than a width of the grid pattern of the first pattern area 33 or a width of the grid pattern of the second pattern area 37. More specifically, the width (E) of the protrusion pattern 35 may be formed in a range of 200 to 1000 nm, i.e., width (E) equals width (B). The width (D) of the grid pattern 31 of the first pattern area 33 or the width of the grid pattern of the second pattern area 37 may be formed in a range of 50 to 100 nm, i.e., width (D) equals width (A). The width (F) of the recesses of the first pattern area 33 or the second grid pattern area 37 may be formed in a range of 50 to 100 nm, i.e, width (F) equals width (C). However, the present disclosure is not limited to this. Also, a height of the protrusion pattern 35 is formed to be higher than a height of the grid patterns 31.
Then, the metal is deposited on the grid patterns 31 and the protrusion pattern 35, and the metal deposited on the grid patterns 31 is removed through the wet etching process, so that the nanoscale metal layer 40 may be formed on the protrusion pattern 35, as illustrated in FIG. 8. The width of the metal may be the same or smaller than the width (E), and the height of the metal layer 40 may be greater than or equal to 100 nm. In the above disclosed embodiments, although the protrusion pattern 35 is illustrated as higher than grid patterns 31 formed in the first pattern area and the second pattern area, the present disclosure is not limited thereto. The protrusion pattern 35 may also be substituted with a wide pattern 35 that is equal in height to the grid patterns 31 (i.e., narrow patterns 31), but is wider than individual narrow patterns 31.
Thus, the transparent substrate having the nano pattern with a large area as illustrated in FIG. 9 can be obtained, which illustrates a top view of transparent substrate, where FIG. 8 is a section view of the area shown in dotted lines. As shown, the metal layer 40 are formed in X and Y directions on top of the protrusion pattern 35 to form a mesh of x and y signal lines x1-x4 and y1-y4 with a plurality of first and second pattern areas 33 and 37.
FIG. 10 illustrates a touchscreen 50 incorporating the transparent substrate having nano pattern, which is provided in area A. A black mask 51 is provided at the periphery of The touchscreen display device 50 to hide any circuitry or visible signal lines, e.g., x and y signal lines of the transparent substrate, which are connected to input and/or output lines 52.
FIG. 11A illustrates a first implementation of the touchscreen 50 in a display device 60. In this embodiment, the touchscreen 50 using a transparent film 32 with signal lines, e.g., x or y signal lines, is adhered using an adhesive 62 between an LCD module 64 and a window 66.
FIG. 11B illustrates a second implementation of the touchscreen 50 in a display device 60. In this embodiment, the touchscreen 50 using glass 34 as the transparent substrate with signal lines, e.g., x or y signal lines, is adhered using an adhesive 62 between an LCD module 64 and a window 66.
FIG. 11C illustrates a third implementation of the touchscreen 50 in a display device 60. In this embodiment, a window 66 having either a film or glass as a substrate with x or y signal lines serve as the touchscreen 50. The touchscreen 50 is adhered to the LCD module 64 using an adhesive 62.
According to the present disclosure, it is advantageous that the nanoscale grid patterns can be uniformly formed throughout a wide area of the transparent substrate.
Also, according to the present disclosure, it is advantageous that the nanoscale metal layer as well as the aforesaid grid patterns can be also uniformly formed on the transparent substrate, thereby enabling the transparent substrate having electrical conductivity equal to ITO to be provided at a low cost.
In addition, the master mold used in the present disclosure is recyclable until it is damaged, causing economical advantages such as the reduction of a raw material charge and a production cost.
Any reference in this specification to “one embodiment,” “an embodiment,” “example embodiment,” etc., means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with any embodiment, it is submitted that it is within the purview of one skilled in the art to effect such feature, structure, or characteristic in connection with other ones of the embodiments.
Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.

Claims

What is claimed is:

1. A touchscreen display device comprising:

a display module; and

an electrically conductive and light transmissive layer provided over the display module and allowing detection of touch input, the electrically conductive and light transmissive layer having

a transparent substrate;

a transparent layer provided over the transparent substrate, the transparent layer having first and second surfaces, which are opposing surfaces, the first surface facing the transparent substrate, the second surface having a plurality of protrusions extending in different directions such that the plurality of first protrusions intersect to form recess regions on the second surface, and the recess regions having a plurality of second protrusions, the second protrusions having a height and a width less than the first protrusions; and

at least one metallic wiring layer formed on the plurality of first protrusions including at locations where the first protrusions intersect.

2. The touchscreen display device of claim 1, wherein the display module is a liquid crystal display module.

3. The touchscreen display device of claim 1, wherein the transparent substrate has first and second surfaces, the first surface of the transparent substrate facing the display module, and the second surface facing the second surface of the transparent layer.

4. The touchscreen display device of claim 1, wherein the second surface of the transparent layer face the display module.

5. The touchscreen display device of claim 1, wherein each of the first protrusions has a width of 200-1000 nm, and each of the second protrusions has a width of 50-100 nm.

6. The touchscreen display device of claim 1, wherein the at least one metallic wiring layer has a thickness greater than a pitch value between two adjacent second protrusions.

7. The touchscreen display device of claim 1, wherein the transparent layer is made of resin material.

8. The touchscreen display device of claim 7, wherein the resin material is one of a thermosetting polymer or a photo-curable polymer, the polymer being one of PET, PC and PI.

9. The touchscreen display device of claim 1, wherein the substrate is at least one of glass or quarts.

10. The touchscreen display device of claim 1, wherein the plurality of first protrusions form a mesh layout on the second surface of the resin layer.

11. The touchscreen display device of claim 1, wherein the plurality of first protrusions comprises a first group of protrusions extending in a first direction and a second group of protrusions extending in a second direction, the first and second directions being different directions.

12. The touchscreen display device of claim 11, wherein the first and second directions are perpendicular to each other such that the recess regions have a rectangular shape.

13. The touchscreen display device of claim 1, wherein a recess is proved between adjacent second protrusions to form a pattern of protrusions and recesses.

14. The touchscreen display device of claim 1, wherein the plurality of first protrusions comprises a first group of protrusions extending in a first direction and a second group of protrusions extending in a second direction, the first and second directions being different directions, the plurality of second protrusions extending in the first direction of the first group of protrusions.

15. The touchscreen display device of claim 1, wherein the at least one metallic wiring layer comprises at least one of Al, Cr, Ag, Cu, Ni, Co or Mo.

16. The touchscreen display device of claim 1, wherein an electrical conductivity of the electrically conductive and light transmissive layer is equal to indium tin oxide (ITO).

17. The touchscreen display device of claim 1, wherein a width of a first protrusion is 200-1000 nm.

18. The touchscreen display device of claim 1, wherein each of the plurality of first protrusions has a width wider than a width of each of the plurality of second protrusions.

19. The touchscreen display device of claim 1, wherein each of the first and second protrusions have a rectangular shape.