CN108550527B

CN108550527B - Graphical method

Info

Publication number: CN108550527B
Application number: CN201810469280.9A
Authority: CN
Inventors: 赵承潭; 李鑫; 黄华
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd
Priority date: 2018-05-16
Filing date: 2018-05-16
Publication date: 2021-01-22
Anticipated expiration: 2038-05-16
Also published as: CN108550527A

Abstract

The embodiment of the present invention provides a graphics method to accurately realize graphics in a specific area. The patterning method includes: fabricating at least one raised structure on a substrate, the position of the raised structure corresponding to the area to be patterned; forming a film layer on the raised structure; using a nano-imprint template to The film layer is patterned. Because at least one protruding structure is fabricated on the substrate before the step of patterning the film layer by using the nanoimprint template, compared with the prior art, nanoimprinting can not be performed in the area other than the protruding structure, and further Accurately implement graphics in specific areas.

Description

Graphical method

Technical Field

The invention relates to the technical field of nanoimprint lithography, in particular to a patterning method.

Background

Nanoimprint technology is a low-cost, fast method of obtaining replicated structures at the nanoscale, which can be used to repeatedly fabricate nanopattern structures on large-area substrates in large quantities.

The nano-imprinting technology realizes pattern transfer by physical deformation of a corrosion inhibitor, the resolution is not limited by factors such as light wavelength and the like, the resolution limit of the traditional photoetching process can be broken through, and the nano-imprinting technology also has the advantages of low cost, large depth-to-width ratio and the like. The nano-processing precision reported at present reaches 2 nanometers and exceeds the resolution ratio which can be achieved by the traditional photoetching technology.

The currently common nanoimprint technology is divided into the following three steps:

the first step is as follows: processing a template; the step generally uses electron beam etching and other means to process the required structure on the silicon or other substrates as a template, and the diffraction limit of electrons is far smaller than that of photons, so that the resolution ratio far higher than that of the photoetching technology can be achieved.

The second step is that: transferring the pattern; coating a layer of photoresist on the surface of a material to be processed, pressing the template formed by the first step on the surface of the photoresist, and transferring the pattern onto the photoresist in a pressurizing mode.

The third step: processing a substrate; the photoresist is solidified by ultraviolet light, after a template is removed, the photoresist which is not completely removed in the second step is etched by etching liquid to expose the surface of the material to be processed, then the material is processed by using a chemical etching method, and all the photoresist is removed after the processing is finished, so that the material with high precision is finally obtained.

The nanoimprint technology has been widely researched in the display industry, and a polarizing layer, a 3D display, a touch electrode, a color film substrate, an array substrate and the like can be realized by a nanoimprint process.

The inventor of the present invention finds that one difficulty of the application of the existing nanoimprint technology in the display field is the realization of patterning, and the display field needs to realize the nanometer pattern in a specific area, but the patterning in the specific area is difficult to realize by the existing nanoimprint technology.

Disclosure of Invention

In view of the above, the present invention provides a patterning method for accurately implementing patterning in a specific area.

In order to achieve the purpose, the invention provides the following technical scheme:

a method of patterning, comprising:

manufacturing at least one protruding structure on a substrate, wherein the position of the protruding structure corresponds to a region needing to be patterned;

forming a film layer on the raised structure;

and patterning the film layer by adopting a nano-imprint template.

Preferably, at least two adjacent raised structures are manufactured on the substrate, and the heights of the adjacent raised structures are different;

the width of the raised structures is less than or equal to the width of the nano-imprinting stamp in a direction parallel to the substrate.

Preferably, the height of the raised structures, which have the smallest height, in a direction perpendicular to the substrate is equal to the depression height of the nano-imprinting stamp.

Preferably, the height difference of the adjacent raised structures along the direction perpendicular to the substrate is not less than the depression depth of the nano-imprinting template.

Preferably, the patterning the film layer by using a nano-imprint template includes:

and sequentially patterning the film layer above the convex structures by adopting a nano-imprint template according to the ascending order of the heights of the convex structures.

Preferably, the patterning the film layer by using a nano-imprint template further includes:

and sequentially shielding the patterned film layer according to the ascending order of the heights of the convex structures.

Preferably, the fabricating of the raised structure on the substrate comprises:

and manufacturing a convex structure on the substrate by adopting a patterning process.

Preferably, the material of the projection structure includes an organic resin, or an inorganic transparent material.

Preferably, the inorganic transparent material includes silicon nitride or silicon oxide.

Preferably, the forming a film layer on the protruding structure includes:

and forming a metal layer on the raised structure by adopting a patterning process.

Compared with the prior art, the scheme of the invention has the following beneficial effects:

the patterning method provided by the embodiment of the invention comprises the steps of firstly manufacturing at least one protruding structure on a substrate, enabling the position of the protruding structure to correspond to a region needing patterning, then forming a film layer on the protruding structure, and patterning the film layer by adopting a nano-imprint template. Compared with the prior art, the method and the device for patterning the film layer have the advantages that the at least one protruding structure is manufactured on the substrate before the step of patterning the film layer by adopting the nano-imprinting template, so that nano-imprinting can not be realized in the region except the protruding structure, and further, the patterning in the specific region can be accurately realized.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural diagram of a prior art nano-imprinting method;

FIG. 2 is a schematic structural diagram of a prior art nano-imprint method for large-area patterning;

FIG. 3 is a flow chart of a graphical method provided by an embodiment of the invention;

fig. 4 is a schematic structural diagram of a film patterned by a nanoimprint method according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a large-area patterning of a film layer by using a nanoimprint method according to an embodiment of the present invention;

fig. 6-9 are schematic structural diagrams of different stages of patterning a film layer in a large area by using a nanoimprint method according to another embodiment of the present invention;

fig. 10-11 are schematic structural diagrams of a metal wire grid polarizer with a larger area fabricated on a color filter substrate at different stages according to an embodiment of the present invention.

The meaning of the various reference symbols of the embodiments of the invention is explained below:

11-a substrate; 12-a film layer; 13-impression glue; 14-nano-imprinting of a template;

120-a metal layer; 41-raised structures; 81-photoresist; 91-black matrix; 92-a color filter layer; 93-a flat protective layer; 921 — red filter layer; 922-green filter layer; 923-blue filter layer.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative only and should not be construed as limiting the invention.

As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present. Further, "connected" or "coupled" as used herein may include wirelessly connected or wirelessly coupled. As used herein, the term "and/or" includes all or any element and all combinations of one or more of the associated listed items.

It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The inventor of the present invention has studied on the prior art, and found that the prior art patterning method using the nanoimprint method includes: forming a film 12 on a substrate 11, as shown in fig. 1, when the film 12 needs to be patterned by a nanoimprint method, coating a layer of imprint glue 13 on the film 12, then pressing a nanoimprint template 14 on the surface of the imprint glue 13, and realizing pattern transfer through physical deformation of the imprint glue 13; and then, curing the imprint glue 13 by adopting ultraviolet light, exposing the film layer 12 which is not covered by the imprint glue 13 after the nano-imprint template 14 is removed, removing the exposed film layer by using an etching method, and then removing the residual imprint glue 13 to finish the patterning of the film layer 12.

The inventors of the present invention have found that the patterning method shown in fig. 1 of the related art has a problem that a region not to be patterned other than the patterned region is also patterned, and it is difficult to perform patterning in a specific region.

In addition, the inventor of the present invention also finds that, when the film layer 12 needs to be patterned in a large area in the prior art, because the size of the nano-imprint template 14 in the prior art is very small and is difficult to be made large, the large-area patterning of the film layer 12 cannot be completed when the imprint glue 13 is imprinted by using the nano-imprint template 14 once, the large-area patterning of the film layer 12 is usually performed by using a splicing manner in the prior art, as shown in fig. 2, the large-area patterning of the film layer 12 is completed by using a multi-splicing manner of the nano-imprint template 14, and only two splices are shown in the figure.

The inventor of the present invention has found that the alignment error of the stitching method shown in fig. 2 in the prior art is very large, mainly because the nano-imprinting template 14 is installed on a roller, only two points on one side can be aligned during alignment, and when the patterning is performed by using this method, the angle deviation of nano-imprinting and the stitching deviation are very large.

The technical scheme of the embodiment of the invention is described below by combining the accompanying drawings.

As shown in fig. 3, fig. 3 is a flowchart of a graphical method according to an embodiment of the present invention, where the method includes:

s301, manufacturing at least one protruding structure on a substrate, wherein the position of the protruding structure corresponds to a region needing to be patterned;

s302, forming a film layer on the protruding structure;

and S303, patterning the film layer by adopting a nano-imprint template.

Specifically, if the patterning is required to be performed in two different areas according to the embodiment of the present invention, as shown in fig. 4, a protruding structure 41 is first fabricated on the substrate 12, two protruding structures 41 are shown in the drawing, and the positions of the two protruding structures 41 correspond to the areas to be patterned.

Preferably, the method of fabricating the bump structure 41 on the substrate 12 according to the embodiment of the present invention includes: fabricating a bump structure 41 on the substrate 12 by a patterning process; the patterning process in the embodiment of the present invention includes a partial or complete process of coating, exposing, developing, etching and removing the photoresist.

Preferably, the material of the protruding structure 41 in the embodiment of the present invention includes an organic resin, or an inorganic transparent material; thus, the material selection cost of the protruding structure of the embodiment of the invention is lower.

Further, in embodiments of the present invention, the inorganic transparent material comprises silicon nitride (SiN)_x) Or silicon oxide (SiO)_x) The cost of the selected material of silicon nitride or silicon oxide is lower, and the bulge structure is easier to manufacture in the actual production process. Of course, in the actual production process, other types of materials may be selected for the bump structures in the embodiments of the present invention, and the materials of the bump structures are not limited in the embodiments of the present invention.

In specific implementation, the material of the bump structure in the specific embodiment of the invention is introduced by taking silicon oxide as an example; in the manufacturing of the bump structure according to the embodiment of the present invention, firstly, a silicon oxide film is deposited on the substrate 12 by a plating method, and the thickness of the deposited silicon oxide film is set according to the height of the bump structure to be formed in practical applications, for example: in practical applications, the height of the raised structures is required to be greater than the depression depth of the nano-imprinting stamp 14 during imprinting.

Then, coating a layer of photoresist on the silicon oxide film, exposing and developing the coated photoresist, and only reserving the photoresist at the position where the protruding structure is required to be formed after the development; then, removing the silicon oxide film in the area which is not covered by the photoresist by adopting an etching method; finally, the remaining photoresist is removed to form the bump structure 41.

As shown in fig. 4, next, a metal layer 120 is formed on the bump structure 41 by using a patterning process, and a specific manufacturing method of the metal layer 120 is similar to that of the bump structure 41, and is not repeated here.

In specific implementation, the material of the metal layer 120 in the specific embodiment of the present invention includes metal materials such as aluminum (Al), silver (Ag), and copper (Cu), and in an actual production process, in consideration of material characteristics and cost performance, the material of the metal layer 120 in the specific embodiment of the present invention is Al.

As shown in fig. 4, the metal layer 120 is then patterned using the nano-imprint template 14; specifically, a layer of imprint glue 13 is coated on the metal layer 120, then the nano-imprint template 14 is pressed on the surface of the imprint glue 13, and the pattern transfer is realized through the physical deformation of the imprint glue 13; then, ultraviolet light is adopted to solidify the imprinting glue 13, after the nano imprinting template 14 is removed, the exposed metal layer is removed by using an etching method, and the residual imprinting glue 13 is removed, so that the patterning of the metal layer 120 is completed; the process of patterning the metal layer 120 using the nano-imprint template 14 is similar to the prior art process of patterning using nano-imprint techniques.

Because the processing process of the nano-imprinting technology does not use visible light or ultraviolet light to process patterns, but uses a mechanical means to transfer the patterns, the method can achieve very high resolution, and the highest resolution reported at present can reach 2 nanometers. In addition, the nano-imprint template can be repeatedly used, so that the processing cost is greatly reduced, and the processing time is effectively shortened; therefore, the nanoimprint technology has the technical advantages of ultrahigh resolution, easiness in mass production, low cost and high consistency.

In an actual production process, when a large area of the metal layer 120 needs to be patterned, the metal layer may be formed by splicing the nano-imprint template 14 multiple times, as shown in fig. 5, where fig. 5 shows an imprint method that uses the nano-imprint template 14 to splice three times.

Although the patterning method shown in fig. 5 can pattern the metal layer 120 in a large area, the alignment accuracy of the nano-imprinting template 14 is not high, and thus, the angle deviation and the stitching deviation are large in a specific imprinting process.

In order to reduce the problem of large angle deviation and large splicing deviation in the nanoimprinting process, in a preferred embodiment, at least two adjacent raised structures 41 are manufactured on the substrate 11, the heights of the adjacent raised structures 41 are different, as shown in fig. 6, two adjacent raised structures 41 are shown in the figure, and the width of the raised structures 41 is smaller than or equal to the width of the nanoimprinting template 14 along the direction parallel to the substrate 11 (i.e., along the horizontal direction), so that multiple splices of the nanoimprinting template 14 can be well realized.

In the embodiment of the present invention, the metal layer 120 is formed on the protruding structure 41 shown in fig. 6, and after the nano-imprint template 14 is used for splicing twice, the metal layer 120 can be patterned in a larger area.

In the embodiment of the present invention, when the metal layer 120 is patterned in a large area by using the nano-imprint template 14 to perform multiple splices, since the embodiment of the present invention manufactures a plurality of adjacent raised structures 41 with different heights, and at this time, the alignment error during nano-imprint is converted into the alignment error during raised structure 41 manufacture, and since the raised structures 41 in the embodiment of the present invention are manufactured by using the patterning process, the maximum splice error in the embodiment of the present invention is limited to the exposure alignment deviation, and the 1 μm deviation can be stably realized.

Preferably, the height of the raised structures 41 with the smallest height in the direction perpendicular to the substrate 11 (i.e. in the vertical direction) is equal to the pressing-down height of the nano-imprinting stamp 14; as shown in fig. 6, the height of the raised structures 41 on the left side of the figure is equal to the depression height of the nano-imprinting stamp 14, i.e. the nano-imprinting stamp 14 can be imprinted exactly at this time, and no other interference phenomenon occurs.

Further, in the direction perpendicular to the substrate 11, the height difference between the adjacent raised structures 41 is not less than the pressing depth of the nano-imprinting template 14, and when the metal layer 120 on each raised structure 41 is patterned, the nano-imprinting template 14 can be properly imprinted without causing other interference phenomena.

In practical implementation, the height difference between adjacent protruding structures 41 may be 0.5 to 2 times the height of the protruding structure 41 with smaller height, such as: the height difference of the adjacent convex structures 41 in fig. 6 is 0.5 to 2 times the height of the convex structure 41 on the left side.

The process of patterning the metal layer 120 in a large area by using the nano-imprint template 14 to perform multiple splicing is described in detail below.

As shown in fig. 7, firstly, a plurality of mutually adjacent raised structures 41 with different heights are fabricated on a substrate 11 by using a patterning process, only two raised structures 41 are shown in the figure, where adjacent means adjacent and contacting, and the specific number of raised structures 41 is set according to the size of the region to be patterned.

As shown in fig. 7, next, a metal layer 120 is formed on each of the raised structures 41 by using a patterning process, a layer of imprint glue 13 is coated on the metal layer 120, and then the metal layer 120 is patterned by using the nano-imprint template 14, where the method for patterning the leftmost metal layer 120 in fig. 7 is similar to the prior art and will not be described again here.

Preferably, as shown in fig. 8, the patterning of the metal layer 120 using the nano-imprint template 14 according to the embodiment of the present invention includes: the metal layer 120 above the raised structures 41 is patterned sequentially using the nano-imprinting template 14 in the order of increasing height of the raised structures 41, i.e.: the metal layer 120 above the bump structure 41 at the middle position is patterned first, and then the metal layer 120 above the bump structure 41 at the rightmost position is patterned, and the specific method for patterning the metal layer 120 above each bump structure 41 according to the embodiment of the present invention is similar to the prior art, and is not described herein again.

Further, as shown in fig. 8, the patterning of the metal layer 120 by using the nano-imprint template 14 according to the embodiment of the present invention further includes: according to the increasing sequence of the heights of the protruding structures 41, the patterned metal layer 120 is sequentially shielded, so that when the metal layer 120 above the protruding structures 41 with higher height is subsequently patterned, the influence of the imprinting glue 13 dropping during imprinting of the nano-imprinting template 14 on the patterned area can be well prevented, and the yield of products can be further improved.

In specific implementation, as shown in fig. 8, in the embodiment of the present invention, the patterned metal layer 120 is shielded by using the photoresist 81, and after the patterning is completed, the photoresist 81 is removed to form the patterned metal layer 120, as shown in fig. 9. According to the specific embodiment of the invention, the photoresist is adopted for shielding, so that the photoresist can be better manufactured in the actual production process, and can be better removed after being patterned, and the production cost can be effectively reduced.

When the metal layer 120 needs to be patterned in a large area, compared with the prior art, the angle deviation and the splicing deviation of nano imprinting can be effectively reduced by adopting the patterning method of the specific embodiment of the invention, the maximum splicing error of the specific embodiment of the invention is limited to the deviation of exposure counterpoint, and the deviation of 1 μm can be stably realized.

A description will be given below with reference to an embodiment, where a WGP (Wire Grid Polarizer) with a larger area is manufactured on a color film substrate by using the patterning method provided in the embodiment of the present invention.

As shown in fig. 10, the color filter substrate includes a black matrix 91, a color filter layer 92 and a flat passivation layer 93 on a substrate 11, the color filter layer 92 includes a red filter layer 921, a green filter layer 922 and a blue filter layer 923, and the specific structure of the color filter substrate is similar to that of the prior art and will not be described herein again.

As shown in fig. 10, a plurality of mutually adjacent raised structures 41 with different heights are formed on the flat protective layer 93, only two raised structures 41 are shown in the figure, and the specific number of raised structures 41 is set according to the size of the region to be patterned.

Next, as shown in fig. 10, a metal layer 120 is formed on each of the protruding structures 41 by using a patterning process, a layer of imprint glue 13 is coated on the metal layer 120, and the metal layer 120 above the protruding structures 41 is patterned sequentially by using the nano-imprint template 14 according to the ascending order of the heights of the protruding structures 41.

Further, as shown in fig. 10, in the embodiment of the present invention, a photoresist 81 is used to shield the patterned metal layer 120, and after all the metal layers 120 are patterned, the photoresist 81 is removed to form the patterned metal layer 120, that is, a WGP structure with a larger area is formed, as shown in fig. 11.

In the actual production process, the patterning method provided by the specific embodiment of the invention can be used for patterning other types of film layers, and is not limited to patterning the metal layer; such as: in the actual production process, the patterning method provided by the embodiment of the invention can be used for patterning the film layers such as Indium Tin Oxide (ITO).

In summary, the patterning method provided in the embodiments of the present invention has the following advantages:

first, a patterning method provided in an embodiment of the present invention is to fabricate at least one protrusion structure on a substrate, where the protrusion structure corresponds to a region to be patterned, and then form a film on the protrusion structure, and pattern the film by using a nano-imprint template. Compared with the prior art, the method and the device for patterning the film layer have the advantages that the at least one protruding structure is manufactured on the substrate before the step of patterning the film layer by adopting the nano-imprinting template, so that nano-imprinting can not be realized in the region except the protruding structure, and further, the patterning in the specific region can be accurately realized.

Secondly, because at least two adjacent raised structures are manufactured on the substrate, the heights of the adjacent raised structures are different, and the width of the raised structures is smaller than or equal to that of the nano-imprinting template along the direction parallel to the substrate, multiple splicing of the nano-imprinting template can be well realized, and large-area patterning of a film layer to be patterned can be further well realized.

Thirdly, when the large-area patterning is carried out on the film layer to be patterned, the maximum splicing error is limited to the deviation of exposure contraposition, and the deviation of 1 μm can be stably realized.

Fourthly, along the direction vertical to the substrate, the height of the protruding structure with the minimum height is equal to the pressing height of the nano-imprinting template; and along the direction perpendicular to the substrate, the height difference of the adjacent raised structures is equal to the pressing-down height of the nano-imprinting template, so that when the film layer on each raised structure is patterned, the nano-imprinting template can be imprinted exactly, and other interference phenomena cannot be caused.

Fifthly, when the nano-imprint template is adopted to pattern the film layer, the film layer which is patterned is sequentially shielded according to the ascending order of the heights of the convex structures, so that the influence of imprint glue dropping during the imprinting of the nano-imprint template on the patterned area can be well prevented, and the yield of products can be improved.

The foregoing is only a partial embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A method of patterning, comprising:

forming a film layer on the raised structure;

patterning the film layer by adopting a nano-imprinting template;

the patterning the film layer by using the nano-imprint template comprises:

coating a layer of impression glue on the film layer;

pressing a nano-imprinting template on the surface of the imprinting glue to realize pattern transfer;

removing the exposed film layer;

and removing the stamping glue, so that the residual film layer is remained on the raised structure.

2. The patterning process of claim 1, wherein at least two adjacent raised structures are formed on said substrate, said adjacent raised structures having different heights;

3. The patterning process of claim 2, wherein the height of the raised structures having the smallest height in a direction perpendicular to the substrate is equal to the depression height of the nano-imprinting stamp.

4. The patterning process of claim 2, wherein the difference in height between adjacent raised structures in a direction perpendicular to the substrate is no less than the depth of depression of the nano-imprinting stamp.

5. The patterning method of claim 2, wherein the patterning the film layer using a nano-imprint template comprises:

6. The patterning method of claim 5, wherein the patterning the film layer using a nano-imprint template further comprises:

7. The patterning process of any one of claims 1 to 6, wherein the forming of the raised structures on the substrate comprises:

8. The patterning process of claim 7, wherein the material of the raised structures comprises an organic resin, or an inorganic transparent material.

9. The patterning process of claim 8, wherein the inorganic transparent material comprises silicon nitride or silicon oxide.

10. The patterning process of claim 1, wherein said forming a layer over said raised structures comprises: