Patterning of complex metal oxide structures

Abstract

The disclosed various embodiments relate to a method for producing a textured surface with nanoparticle ink using nanoimprint lithography. The present invention provides a method that enables a substrate to be flexibly patterned with features having complex geometric shapes.

Description

Technology Field

[0001] Cross-reference regarding related applications

[0002] This application claims the benefit of priority to U.S. provisional patent application No. 62 / 565,703, filed on September 29, 2107, the entire disclosure of which is incorporated herein by reference.

[0003] Statement regarding government support

[0004] This invention was created with government support under CMMI-1025020 approval granted by the National Science Foundation (NSF). The U.S. government holds specific rights in this invention. Background Technology

[0005] Nanostructured metal, metal oxide, and metal nitride structures are attracting attention for applications as optical devices, metamaterials, and metasurfaces. Many applications involving optical devices and metamaterials / metasurfaces require complex geometries. These include structures with high aspect ratios (height to width exceeding 4:1), structures with variable tilt angles relative to the normal of the substrate surface (e.g., blaze grating), and patterns of features where the height and orientation of individual components differ and / or the regional density of features varies significantly (e.g., some regions of the pattern have a high density of closely spaced features, while other regions contain no features or contain a relatively sparse number of features spaced far apart relative to their size). Each of these requirements is difficult to satisfy using conventional nanoimprint lithography. means of solving the problem

[0006] A method for manufacturing a textured surface is provided. Such a method comprises the steps of placing a template on a substrate and flattening the template with nanoparticle ink.

[0007] A method for manufacturing a textured surface is provided. Such a method comprises the steps of flattening an imprinted template with nanoparticle ink to form a transfer print master and bringing the transfer print master into contact with a substrate.

[0008] A method for producing a textured surface is provided. Such a method comprises the steps of placing a template on a substrate, imprinting the template with a mold comprising a plurality of features that penetrate the template to form an imprinted template, flattening the imprinted template with nanoparticle ink, annealing the nanoparticle ink, and removing the imprinted template. In such a method, the step of imprinting creates an imprinted feature in the template whose shape and position substantially correspond to a feature on the mold, and the nanoparticle ink substantially fills the imprinted feature in the template, and the nanoparticle ink comprises indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0009] A method for producing a textured surface is provided. Such a method comprises the steps of placing a template on a first substrate; imprinting the template with a mold comprising a plurality of features penetrating the template to form an imprinted template; flattening the imprinted template with nanoparticle ink to form a transfer print master; annealing the nanoparticle ink; bringing the transfer print master into contact with a second substrate; and removing the transfer print master to provide a plurality of features placed on the second substrate. In such a method, the step of imprinting creates an imprinted feature in the template whose shape and position substantially correspond to a feature on the mold, and the nanoparticle ink substantially fills the imprinted feature in the template, and the nanoparticle ink comprises indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0010] In several embodiments, the present method can easily produce complex structural geometries having very diverse feature sizes and feature distributions on a surface. In several embodiments, advantages of the present invention compared to current levels of technology include a relatively small degree of feature shrinkage during calcination after other post-processing and mechanical robustness. Advantageously, in several embodiments, the method enables the production of high aspect ratio structures (height:width greater than 4:1), structures with variable inclination angles relative to the normal of the substrate surface, and patterns of features in which the height and orientation of individual components differ and / or the local density of features varies significantly. Advantageously, in several embodiments, the method enables the production of patterns having high feature densities that are closely spaced together, while other regions of the pattern contain no features or contain a relatively sparse number of features that are far apart relative to the feature size. Brief explanation of the drawing

[0011] In drawings that are not necessarily drawn to actual scale, similar numbers describe substantially similar components throughout several drawings. The drawings generally illustrate various embodiments of the invention as examples, but without limitation. The features depicted in the drawings are not to actual scale and are for illustrative and clear purposes only. FIG. 1 is a schematic diagram of a method for manufacturing a textured surface according to various embodiments. FIG. 2 is a schematic diagram of a feature having an acute angle with respect to the surface of a mold according to various embodiments. FIG. 3 is a schematic diagram of a mold having a portion having a high feature density and a portion having a low feature density according to various embodiments. FIG. 4 is a schematic diagram of a method for manufacturing a textured surface using a transfer print master according to various embodiments. Specific details for implementing the invention

[0012] Now, specifically, we will refer to specific embodiments of the disclosed subject of the claim, which are partially illustrated in the attached drawings. Although the disclosed subject of the claim will be described together with the listed claims, it will be understood that the exemplified subject of the claim is not intended to limit the scope of the claim to the disclosed subject.

[0013] Throughout this literature, values ​​expressed in a range format should be interpreted flexibly to include not only numeric values ​​explicitly stated as limits of the range, but also all individual numeric values ​​or sub-ranges included within such ranges, as each numeric value and sub-range is explicitly stated. For example, a range of “about 0.1% to about 5%” or “about 0.1% to 5%” should be interpreted to include not only about 0.1% to about 5%, but also individual values ​​(e.g., 1%, 2%, 3%, and 4%) and sub-ranges within the indicated range (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%). Unless otherwise stated, the notation “about X to Y” has the same meaning as “about X to about Y”. Likewise, unless otherwise noted, the notation “about X, Y, or about Z” has the same meaning as “about X, about Y, or about Z”.

[0014] In these documents, unless otherwise clearly indicated in the context, the terms of articles (“a,” “an,” or “the”) are used to include one or more. Unless otherwise indicated, the term “or” is used to refer to a non-exclusive “or.” The notations “at least one of A and B” or “at least one of A or B” have the same meaning as “A, B, or A and B.” Furthermore, it should be understood that the grammar or terminology used herein is for illustrative purposes only and is non-restrictive, unless otherwise specified. Any section headings are intended to aid in reading the documents and are not to be interpreted restrictively; information related to a section heading may or may not be contained in the corresponding section.

[0015] In the method described herein, operations may be performed in any order without departing from the principles of the invention, except where a temporal or operational order is explicitly stated. Additionally, specific operations may be performed simultaneously unless the express claim language describes that the operations are performed separately. For example, a claimed operation performing X and a claimed operation performing Y may be performed simultaneously in a single operation, and the resulting process will be included within the literal scope of the claimed process.

[0016] As used herein, the term “about” may allow for a degree of variability in the value or range, for example, within 10%, within 5%, or within 1% of the limits of the described value or range, and includes the precisely described value and range.

[0017] As used herein, the term “substantially” refers to most or almost, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or at 100%. As used herein, the term “substantially without” may mean having no or having a small amount, and accordingly, the amount of the provided substance does not affect the material properties of the composition containing the substance, and accordingly, the composition is about 0% to about 5% by weight of the substance, or about 0% to about 1% by weight, or about 5% by weight or less, or less than about 4.5% by weight, equal or greater, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001% by weight or less. The term “substantially free of” may mean having a small amount, and accordingly, the composition is about 0% to about 5% by weight of the material, or about 0% to about 1% by weight, or about 5% by weight or less, or less than about 4.5% by weight, equal to, or greater than, 4, 3.5, 3, 2.5, 2, 1.5, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.01, or about 0.001% by weight or less, or about 0% by weight.

[0018] As used herein with respect to molecules or organic groups as defined herein, the term “substituted” refers to a state in which one or more hydrogen atoms contained therein are replaced by one or more non-hydrogen atoms. As used herein, the terms “functional group” or “substituent” refer to a group that can be substituted or is substituted on a molecular or organic group. Examples of substituents or functional groups are, but are not limited to, halogens (e.g., F, Cl, Br, and I); oxygen atoms within groups such as hydroxyl groups, alkoxy groups, aryloxy groups, aralkyloxy groups, oxo(carbonyl) groups, carboxyl groups including carboxylic acids, carboxylates, and carboxylate esters; sulfur atoms within groups such as thiol groups, alkyl and aryl sulfide groups, sulfoxide groups, sulfonyl groups, sulfonyl groups, and sulfonamide groups; It includes nitrogen atoms within groups such as amine, hydroxyamine, nitrile, nitro group, N-oxide, hydrazide, azide, and enamine; and other heteroatoms within various other groups. Non-limiting examples of substituents that may be bonded to the substituted carbon (or other) atom are F, Cl, Br, I, OR, OC(O)N(R)2, CN, NO, NO2, ONO2, azido, CF3, OCF3, R, O (oxo), S (thiono), C(O), S(O), methylenedioxy, ethylenedioxy, N(R)2, SR, SOR, SO2R, SO2N(R)2, SO3R, C(O)R, C(O)C(O)R, C(O)CH2C(O)R, C(S)R, C(O)OR, OC(O)R, C(O)N(R)2, OC(O)N(R)2, C(S)N(R)2, (CH2) 0-2 N(R)C(O)R, (CH2) 0-2N(R)N(R)2, N(R)N(R)C(O)R, N(R)N(R)C(O)OR, N(R)N(R)CON(R)2, N(R)SO2R, N(R)SO2N(R)2, N(R)C(O)OR, N(R)C(O)R, N(R)C(S)R, N(R)C(O)N(R)2, N(R)C(S)N(R)2, N(COR)COR, N(OR)R, C(=NH)N(R)2, C(O)N(OR)R, and C(=NOR)R, where R is a hydrogen or carbonaceous moiety; R is hydrogen, (C1-C 100 It may be hydrocarbyl, alkyl, acyl, cycloalkyl, aryl, aralkyl, heterocyclyl, heteroaryl, or heteroarylalkyl; or two R groups bonded to or adjacent nitrogen atoms may form a heterocyclyl with the nitrogen atom or atoms.

[0019] As used herein, the term “alkyl” refers to straight-chain and branched alkyl groups and cycloalkyl groups having 1 to 40 carbon atoms, 1 to about 20 carbon atoms, 1 to 12 carbon atoms, or, in some embodiments, 1 to 8 carbon atoms. Examples of straight-chain alkyl groups include alkyl groups having 1 to 8 carbon atoms, e.g., methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl groups. Examples of branched alkyl groups include, but are not limited to, isopropyl, iso-butyl, sec-butyl, t-butyl, neopentyl, isopentyl, and 2,2-dimethylpropyl groups. As used herein, the term “alkyl” includes n-alkyl, isoalkyl, and antiisoalkyl groups, as well as other branched chain forms of alkyl. Representative substituted alkyl groups may be substituted one or more times with any of the groups listed herein, for example, amino, hydroxy, cyano, carboxyl, nitro, thio, alkoxy, and halogen groups.

[0020] As used herein, the term “radiation” refers to particles of energy traveling through a medium or space. Examples of radiation are visible light, infrared radiation, microwaves, radio waves, very low frequency waves, extremely low frequency waves, thermal radiation (heat), and blackbody radiation.

[0021] As used herein, the term “light” refers to electromagnetic radiation within and near wavelengths visible to the human eye, and includes extreme ultraviolet (UV) light and infrared light with wavelengths of about 10 nm to about 300,000 nm. The term “light” also includes microwave radiation with frequencies of about 300 MHz to about 300 GHz.

[0022] As used herein, "UV light" refers to ultraviolet light, which is electromagnetic radiation with a wavelength of about 10 nm to about 400 nm.

[0023] As used herein, the term “infrared light” refers to electromagnetic radiation with a wavelength of about 0.7 micrometers to about 300 micrometers.

[0024] As used herein, "solvent" refers to a liquid capable of dissolving a solid, liquid, or gas. Non-limiting examples of solvents are silicon, organic compounds, water, alcohols, ionic liquids, and supercritical fluids.

[0025] As used herein, the term “coating” refers to a continuous or discontinuous layer of material on a coated surface, the layer of material may penetrate the surface and fill regions such as pores, and the layer of material may have any three-dimensional shape, including flat or curved planes. In one example, the coating may be formed on one or more surfaces by immersion in a bath of coating material, any of such surfaces may be porous or non-porous.

[0026] As used herein, the term “surface” refers to the boundary or side of an object, and the boundary or side may have any perimeter shape, may have any three-dimensional shape including flat, curved, or angled, and the boundary or side may be continuous or discontinuous.

[0027] Method for manufacturing a textured surface

[0028] A method for manufacturing a textured surface is provided. Such a method comprises the steps of: placing a template on a substrate; and flattening the template with nanoparticle ink.

[0029] The substrate may be a non-conductive and non-reactive substrate, such as glass, quartz, or a polymer resin such as a PET sheet or a polyimide sheet. In some embodiments, the substrate is indium tin oxide (ITO) coated glass silicon dioxide.

[0030] In some embodiments, the template may be a crosslinked material. The template may be a polymer resin. For example, the template may be made of a flexible and deformable polymer material such as polydimethylsiloxane (PDMS), polymethyl methacrylate (PMMA)-crosslinked or non-crosslinked, other monomer UV-resins, polyurethane, or perfluoropolyether (PFPE). A planarization step may be performed by spin-coating or blade-coating a nanoparticle ink onto the template. The template may be deposited on a substrate by casting a mixture comprising a PDMS precursor and a curing agent, and then curing at a temperature greater than 50°C. If light is used for curing, the temperature may be selected from temperatures less than 50°C. The template may have a thickness of 0.01 mm to about 5 mm, or about 0.5 mm to about 4.5 mm, or about 1 mm to about 3 mm. In some embodiments, the template has a thickness of about 0.5 mm, about 1 mm, about 1.5 mm, about 2 mm, about 2.5 mm, about 3 mm, about 3.5 mm, about 4 mm, about 4.5 mm, about 5 mm, or any range or sub-range between these values.

[0031] Nanoparticle ink may exist as a dispersion of nanoparticles in a solvent. Nanoparticle ink may include nanoparticles comprising indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, graphene, graphene oxide, or a combination thereof.

[0032] In some embodiments, the nanoparticles have a number-averaged or volume-averaged particle size of about 1 nm to about 20 nm. In some embodiments, the nanoparticles have a number-averaged particle size of about 1 nm to about 19 nm, about 2 nm to about 18 nm, about 3 nm to about 17 nm, about 4 nm to about 16 nm, about 5 nm to about 15 nm, about 6 nm to about 14 nm, about 7 nm to about 13 nm, or any sub-range therein. In some embodiments, the nanoparticles have a volume-average particle size of about 1 nm, about 2 nm, about 3 nm, about 4 nm, about 5 nm, about 6 nm, about 7 nm, about 8 nm, about 9 nm, about 10 nm, about 11 nm, about 12 nm, about 13 nm, about 14 nm, about 15 nm, about 16 nm, about 17 nm, about 18 nm, about 19 nm, about 20 nm, or any range or sub-range between these values. In some embodiments, the nanoparticles are crystalline.

[0033] In some embodiments, the dispersion has an alcohol solvent as a liquid phase. In some embodiments, the alcohol is methanol, isopropanol, 1,2-propanediol, or a mixture thereof. In some embodiments, the alcohol may be ethanol, butanol, ethylene glycol, butanediol (1,2 or 1,3 or 1,4) and a mixture thereof. In some embodiments, the nanoparticle ink may include a binder component. In some embodiments, the binder component may include a siloxane. The binder may be present in the dispersion as a sol-gel precursor.

[0034] FIG. 1 illustrates a mold (100) having a plurality of features (110), a substrate (120), and a template (130). After imprinting the template with the mold, the imprinted features (140) within the template substantially correspond in shape and position to features on the mold. To substantially fill the imprinted features with nanoparticle ink (160), the imprinted template may be flattened with nanoparticle ink (150). After removing the template, the substrate comprises features (170) composed of nanoparticle material from the nanoparticle ink.

[0035] In some embodiments, the top surface of the template (130) (e.g., the surface to be imprinted) may be coated with a material capable of creating a hydrophobic / hydrophilic contrast between the top surface of the template and the imprinted feature / cavity prior to imprinting. Such a coating may fill the feature without leaving a residual layer on the surface of the template.

[0036] The method may further include the step of imprinting a mold with a mold comprising a plurality of features that penetrate the mold to form an imprinted mold. The mold may be manufactured from a hard mold, for example, PDMS (polydimethylsiloxane), PUA (polyurethane acrylate), PMMA (polymethyl methacrylate), silicon, nickel, quartz, or ZrO2. Imprinting may be performed manually or with a suitable device such as a Nanonex NX-2000 or NX-2608BA. In some embodiments, the mold has at least one substantially flat surface, and at least one of the features has a side that forms an acute angle with the mold. The acute angle may be in the range of about 10 to about 89 degrees, about 20 to about 60 degrees, or about 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or less than, equal to, or greater than about 89 degrees. FIG. 2 illustrates a mold (200) having a feature (210) that is an acute angle (220) with respect to a flat surface on the mold.

[0037] The feature may have a height:width aspect ratio of about 2:1 to about 10:1, about 3:1 to 10:1, about 4:1 to about 10:1, about 5:1 to about 10:1, about 6:1 to about 10:1, about 7:1 to about 10:1, about 9:1 to about 10:1, or any range or sub-range between these values. In some embodiments, the feature may have a height:width aspect ratio of about 2:1, about 3:1, about 4:1, about 5:1, about 6:1, about 7:1, about 8:1, about 9:1, about 10:1, or any range or sub-range between these values.

[0038] The feature may have a width:height aspect ratio of about 2:1 to about 10:1, about 3:1 to 10:1, about 4:1 to about 10:1, about 5:1 to about 10:1, about 6:1 to about 10:1, about 7:1 to about 10:1, about 9:1 to about 10:1, or any range or sub-range between these values. In some embodiments, the feature may have a width:height aspect ratio of about 2:1, about 3:1, about 4:1, about 5:1, about 6:1, about 7:1, about 8:1, about 9:1, about 10:1, or any range or sub-range between these values.

[0039] In some embodiments, the height of the feature may be about 0.05 microns to about 30 microns, about 0.5 microns to about 25 microns, about 1 micron to about 22 microns, about 2 microns to about 20 microns, about 3 microns to about 18 microns, about 4 microns to about 16 microns, about 5 microns to about 14 microns, about 6 microns to about 12 microns, or any range or sub-range between these values. The height of the feature may be about 0.05 microns, 1 micron, about 2 microns, about 3 microns, about 4 microns, about 5 microns, about 6 microns, about 7 microns, about 8 microns, about 9 microns, about 10 microns, about 11 microns, about 12 microns, about 13 microns, about 14 microns, about 15 microns, about 16 microns, about 17 microns, about 18 microns, about 19 microns, about 20 microns, about 21 microns, about 22 microns, about 23 microns, about 24 microns, about 25 microns, or any range or sub-range between these values.

[0040] In some embodiments, the width of the feature may be about 0.05 microns to about 30 microns, about 0.5 microns to about 25 microns, about 1 micron to about 22 microns, about 2 microns to about 20 microns, about 3 microns to about 18 microns, about 4 microns to about 16 microns, about 5 microns to about 14 microns, about 6 microns to about 12 microns, or any range or sub-range between these values. The width of the feature may be about 0.05 microns to about 1 micron, about 2 microns, about 3 microns, about 4 microns, about 5 microns, about 6 microns, about 7 microns, about 8 microns, about 9 microns, about 10 microns, about 11 microns, about 12 microns, about 13 microns, about 14 microns, about 15 microns, about 16 microns, about 17 microns, about 18 microns, about 19 microns, about 20 microns, about 21 microns, about 22 microns, about 23 microns, about 24 microns, about 25 microns, or any range or sub-range between these values.

[0041] In some embodiments, the depth of the feature may be about 0.05 microns to about 30 microns, 0.5 microns to about 25 microns, about 1 micron to about 22 microns, about 2 microns to about 20 microns, about 3 microns to about 18 microns, about 4 microns to about 16 microns, about 5 microns to about 14 microns, about 6 microns to about 12 microns, or any range or sub-range between these values. The depth of the feature may be about 0.05 microns, 1 micron, about 2 microns, about 3 microns, about 4 microns, about 5 microns, about 6 microns, about 7 microns, about 8 microns, about 9 microns, about 10 microns, about 11 microns, about 12 microns, about 13 microns, about 14 microns, about 15 microns, about 16 microns, about 17 microns, about 18 microns, about 19 microns, about 20 microns, about 21 microns, about 22 microns, about 23 microns, about 24 microns, about 25 microns, or any range or sub-range between these values.

[0042] In some embodiments, the features are arranged in a periodic pattern. In some embodiments, the features are arranged randomly. In some embodiments, the features are arranged in a non-periodic pattern. In some embodiments, features on the mold may be arranged such that parts of the mold have a high local feature density that are closely spaced together, and other parts of the mold have a pattern that contains no features or contains relatively few features that are far apart from each other relative to the feature size. FIG. 3 illustrates parts of the mold (300) having a high feature density (320) that are closely spaced together, and parts of the mold having relatively few features (310) that are far apart from each other relative to the feature size.

[0043] In some embodiments, the separation between any two features may be about 0.05 microns to about 1000 microns, about 5 microns to about 900 microns, about 10 microns to about 800 microns, about 20 microns to about 700 microns, about 50 microns to about 600 microns, about 75 microns to about 500 microns, about 100 microns to about 400 microns, or any range or sub-range between these values.

[0044] Such separation between any two features is about 0.05 microns, about 1 micron, about 5 microns, about 10 microns, about 15 microns, about 25 microns, about 35 microns, about 45 microns, about 55 microns, about 65 microns, about 75 microns, about 85 microns, about 95 microns, about 105 microns, about 115 microns, about 125 microns, about 135 microns, about 145 microns, about 155 microns, about 165 microns, about 175 microns, about 185 microns, about 195 microns, about 205 microns, about 215 microns, about 225 microns, about 235 microns, about 245 microns, about 255 microns, about 265 microns, about 275 microns, about 285 microns, about 295 microns, about 305 microns, about 315 microns, about 325 microns, about 335 microns, about 345 microns, about 355 microns, about 365 microns, about 375 microns, about 385 microns, about 395 microns, about 405 microns, about 415 microns, about 425 microns, about 435 microns, about 445 microns, about 455 microns, about 465 microns, about 475 microns, about 485 microns, about 495 microns, or any range or sub-range between these values.

[0045] In some embodiments, the imprinting includes residue-free imprint lithography. Residue-free imprinting may be based on adjusting the surface energy / tension of the template, substrate, and ink, and adjusting the ink concentration and coating speed.

[0046] In some embodiments, imprinting creates an imprinted feature in a template that substantially corresponds to a feature on the mold in shape and position. Thus, imprinting can create a negative feature in the template that corresponds to the size and position of a feature on the mold. Flattening the template with the imprinted feature can be achieved by spin-coating a nanoparticle ink to substantially fill the imprinted feature in the template.

[0047] The method may further include the step of first annealing the imprinted template. The first annealing may include heating, microwave irradiation, visible light irradiation, infrared irradiation, and ultraviolet irradiation. In embodiments where electromagnetic radiation is used in the annealing, the light source may be constant, or the electromagnetic radiation may be directed through a pulsed light source that delivers concentrated pulses of light. In some embodiments, the annealing comprises heating to a temperature of 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, 800 °C, 900 °C, or 1000 °C, or any range or sub-range therein. In some embodiments, the annealing is performed at a temperature of 100 to 500 °C for a period of 5 minutes to 2 hours. In some embodiments, annealing is performed at a temperature of 100°C to 1000°C for 5, 10, 15, 20, 25, 30, 40, 50, 60, 70, 80, 90, 100, 110, or 120 minutes, or for any range or sub-range between these values.

[0048] In some embodiments, the method includes the step of removing a template or an imprinted template from a substrate. Removing the template or an imprinted template may include melting, calcination, or irradiation using microwave irradiation, visible light, infrared light, or ultraviolet light. When the template or an imprinted template is removed, a feature corresponding to the size and location of the feature on the mold made of cured or annealed nanoparticle ink appears.

[0049] A second annealing of the substrate and nanoparticle ink features may be performed under the conditions described herein. In some embodiments, the first annealing dries / fuses the particles within the template. In some embodiments, the second annealing promotes bonding and adhesion to the substrate and between the nanoparticles.

[0050] In some embodiments, a method for producing a textured surface is provided. Such a method comprises the steps of placing a template on a substrate, imprinting the template with a mold comprising a plurality of features that penetrate the template to form an imprinted template, flattening the imprinted template with nanoparticle ink, annealing the nanoparticle ink, and removing the imprinted template. In such a method, the step of imprinting creates an imprinted feature in the template whose shape and position substantially correspond to a feature on the mold, and the nanoparticle ink substantially fills the imprinted feature in the template, and the nanoparticle ink comprises indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0051] Method for manufacturing a textured surface using a transfer print master

[0052] Methods for manufacturing textured surfaces using a transfer print master share many similarities with the method described herein. Any material, method, and technique used previously may also be used in the manufacturing method below.

[0053] In some embodiments, a method for producing a textured surface is provided. Such a method comprises the steps of planarizing an imprinted template with nanoparticle ink to form a transfer print master and bringing the transfer print master into contact with a substrate. The composition of the nanoparticle ink and the substrate may be as described herein. The transfer print master may have any composition suitable for the template or imprinted template as described herein.

[0054] In some embodiments, the contact may involve a sheet-based or roll-to-roll transfer process. The method may further include the steps of placing a template on a first substrate and imprinting the template with a mold comprising a plurality of features that penetrate the template to form an imprinted template. In some embodiments, the method further includes the step of removing a transfer print master to provide a plurality of features placed on a second substrate. Removing the transfer print master may be accomplished, for example, by melting, calcination, or irradiation using microwave irradiation, visible light, infrared light, or ultraviolet light. In some cases, the light may be pulsed.

[0055] In some embodiments, the surface of the template may include a hard coating. The hard coating may include silica, perfluoropolyether, fluoro-containing acrylate, epoxide, fluoro-modified silica material, or a mixture thereof.

[0056] In some embodiments, the imprinted template comprises a cross-linked material. In some embodiments, the template comprises a polymer resin. The template may comprise any material described herein. Thus, imprinting can create intaglio features within the template corresponding to the size and location of features on the mold. Flattening the template with imprinted features can be achieved by spin-coating a nanoparticle ink to substantially fill the imprinted features within the template.

[0057] In some embodiments, the imprinting comprises residue-free imprint lithography. Imprinting using or without residue-free imprint lithography produces an imprinted feature in an imprinted template that substantially corresponds to the shape and location of a feature on a mold. In some embodiments, a nanoparticle ink substantially fills the imprinted feature in the imprinted template. The nanoparticle ink may comprise indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0058] The size, shape, and spacing of the features may be as already described herein. In some embodiments, the method further includes the step of annealing the substrate. The annealing may be performed using any of the methods and conditions already described herein. In some embodiments, the annealing includes heating, microwave irradiation, visible light irradiation, infrared irradiation, and ultraviolet irradiation.

[0059] FIG. 4 illustrates a mold (400), a substrate (420), and a template (430) having a plurality of features (410). After imprinting the template with the mold, the imprinted features (440) within the template have shapes and positions substantially corresponding to features on the mold. To substantially fill the imprinted features with nanoparticle ink (460) and to form a transfer print master (465), the imprinted template may be flattened with nanoparticle ink (450). The transfer print master may come into contact with a second substrate (470), and after the removal of the transfer print master, the second substrate is made of nanoparticle material from the nanoparticle ink and has features (480) placed thereon.

[0060] In some embodiments, the transfer print master (465) and the nanoparticle ink (460) are annealed before contacting the second substrate (470). The template may comprise a material transparent to irradiation used to heat, anneale, or both of the structure without substantially heating the transfer print master.

[0061] A manufactured article comprising a textured surface may be formed by any method described herein. Examples of such articles that may be manufactured using the method described herein include, but are not limited to, lenses, flat lenses, meta-lenses, displays, flexible displays, touch panels, sensor surfaces, shielding foils, and blaze gratings. Optionally, the article may be optically transparent. For example, the article may be optically transparent to electromagnetic radiation having wavelengths between the visible light and near-infrared spectrum (e.g., within the range of about 400 nm to about 1400 nm). The article may be a device, such as a virtual reality device or an augmented reality device, or a component thereof. For example, the article may be a component of a virtual reality or augmented reality lens, glasses, or goggles.

[0062] In some embodiments, a method for producing a textured surface is provided. Such a method comprises the steps of placing a template on a first substrate, imprinting the template with a mold comprising a plurality of features penetrating the template to form an imprinted template, flattening the imprinted template with nanoparticle ink to form a transfer print master, annealing the nanoparticle ink, bringing the transfer print master into contact with a second substrate, and removing the transfer print master to provide a plurality of features placed on the second substrate. In such a method, the step of imprinting creates an imprinted feature in the template whose shape and position substantially correspond to a feature on the mold, and the nanoparticle ink substantially fills the imprinted feature in the template, and the nanoparticle ink comprises indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0063] Features deposited using the method described herein may result in structures having residual nano-porousness. Such porosity exists in films coated on a surface from nanoparticle-based inks, in features printed directly onto a substrate, and also in features fabricated in a master for subsequent transfer to a substrate or for the recovery of isolated structures.

[0064] Furthermore, such porosity may result when using an ink containing only a nanoparticle dispersion, or when using an ink containing both nanoparticles and sol-gel type precursors that produce the desired product or binder or other binder material included in the feature. In some cases, such residual porosity is desirable, for example, for ion transport through sensors or battery electrodes. In other cases, residual porosity is detrimental to structural properties, mechanical stability performance during calcination, shrinkage, or both.

[0065] Reduction of residual porosity (densification) can modulate material properties, including refractive index, conductivity, and the like, and improve mechanical stability. Such densification is enhanced by the conduction reaction described herein and / or deposition within the residual pores of the feature to alter properties. In some embodiments, deposition involves using chemical vapor deposition (CVD) to deposit a material within the pores of the feature described herein in a controlled amount, composition, thickness, or any combination of these properties.

[0066] In some embodiments, deposition involves using atomic layer deposition (ALD) to deposit a material into the pores of the features described herein in a controlled amount, composition, thickness, or any combination of these characteristics. In some embodiments, CVD or ALD deposition may deposit a material of substantially the same composition as the pore feature or of a different composition from the pore feature. The ALD process may improve the mechanical stability of printed patterns and structures created within the mold prior to transfer or mold removal, which may enable easier pattern transfer.

[0067] In some embodiments, an adhesive layer (of the same or different composition as the composition of the feature being patterned) may be applied to the structure to be transferred using ALD, CVD, or both. In some embodiments, ALD, CVD, or both may also be used to improve the adhesion of the feature described herein to a substrate. In some embodiments, the surface roughness of the feature described herein may be reduced using ALD, CVD, or both.

[0068] The ALD process described herein can be applied to structures fabricated by conventional NIL (nanoimprint lithography) printing using metal oxide ink. Structures fabricated by the NIL printing process described in [Kothari, R ; Beaulieu, MR; Hendricks, NR; Li, SK; Watkins, JJ, Chemistry of materials Volume: 29 Issue: 9 Pages: 3908-3918] can be processed by the ALD process described herein.

[0069] In ALD, a surface or substrate is subsequently exposed to a first reactant and a second reactant. The first and second reactants are deposited in a non-overlapping manner. In ALD, the deposition of a reactive material, such as the first reactant, on a surface is limited by the amount of reaction sites on the surface. Once all reaction sites are consumed, no further reaction (e.g., growth of layer thickness or filling of pores) may occur until additional reactive material is added. Any remaining molecules of the first reactant may be flushed out and removed before the addition and deposition of the second reactant. Thus, the second reactant is deposited after the deposition of the first reactant. A single ALD cycle comprises depositing the first reactant, optionally flushing out any excess of the first reactant, depositing the second reactant, and optionally flushing out any excess of the second reactant. A successive cycle of this process can result in fine control of the thickness of the deposited layer or the size of the reduced porosity.

[0070] Deposition can be performed to impart various reductions in porosity, ranging from a thin surface coating of pores to substantial pore filling. Such deposition can be performed within a film coated with a nanoparticle-based ink, within an independent printed feature, or within a nanoparticle composition contained within a feature of a master mold. Such deposition can be performed before or after the calcination (curing or annealing) of the coated or printed film and feature.

[0071] In some embodiments, a spatial ALD process may be used. In spatial ALD, reactants (first reactant and second reactant) are spatially separated by an inert gas, and the substrate may be moved relative to the ALD head, or the ALD head may be moved relative to the substrate. Spatial ALD may be used for roll-to-roll processing of features.

[0072] In some embodiments, a method for producing a textured surface comprises the step of performing at least one cycle of atomic layer deposition (ALD) on an imprinted feature, wherein the ALD comprises depositing a first reactant and a second reactant, and the first reactant is MX y , MR y , M(NR) y , M(OR) y , MX y R z , MX y (NR) z , MX y (OR) z It comprises , MCp2, or a combination thereof, and the second reactant comprises water or oxygen. Each y and z are independently integers from 2 to 8. Each X is independently F, Cl, Br, or I. Each R is independently hydrogen or substituted or unsubstituted C 1-20 It is an alkyl, and Cp is a substituted or unsubstituted cyclopentadienyl.

[0073] Suitable metals may include Al, Ti, Si, Cu, Pd, Ni, Ru, Ta, Zr, Zn, In, Hf, Sn, Pt, and combinations thereof. In some embodiments, the metal is Ti. In some embodiments, the first reactant is tetrakis(dimethylamino)titanium (TDMAT) having the following structure.

[0074]

[0075] Suitable second reactants include water, oxygen, and ozone. In some embodiments, the second reactant is water. The second reactant reacts with the first reactant in the pores on the surface of one or more features, or in both. For example, the reaction of TDMAT with water produces TiO2 on one or more features, in the pores of one or more features, or in both. ALD may be carried out at a temperature of about 100 °C to about 800 °C, about 200 to 800 °C, 200 to 700 °C, 200 to 600 °C, 200 to 500 °C, 200 to 400 °C, or 200 to 300 °C. In some embodiments, ALD may be performed at a temperature of about 100 ℃, about 200 ℃, 250 ℃, 300 ℃, 350 ℃, 400 ℃, 450 ℃, 500 ℃, 550 ℃, 600 ℃, 650 ℃, 700 ℃, 750 ℃, 800 ℃, or any range between these values. In some embodiments, ALD is performed at a temperature of 250 ℃.

[0076] The thickness of the deposited material after each ALD cycle may be about 0.01 Å to 1.0 Å, 0.05 Å to 1.0 Å, 0.1 Å to 0.9 Å, 0.1 Å to 0.8 Å, 0.1 Å to 0.7 Å, 0.2 Å to 0.7 Å, 0.2 Å to 0.6 Å, or any range or sub-range between these values. In some embodiments, the thickness of the deposited material after each ALD cycle may be 0.01 Å, 0.05 Å, 0.2 Å, 0.3 Å, 0.4 Å, 0.5 Å, 0.6 Å, 0.7 Å, 0.8 Å, 0.9 Å, 1.0 Å, or any range between these values. The number of ALD cycles used may be about 1 to 5000 cycles, 1 to 4000 cycles, 1 to 3000 cycles, 1 to 2000 cycles, 1 to 1000 cycles, 1 to 500 cycles, 1 to 400 cycles, 1 to 300 cycles, 1 to 200 cycles, 1 to 100 cycles, 1 to 90 cycles, 1 to 80 cycles, 1 to 70 cycles, 1 to 60 cycles, 1 to 50 cycles, 1 to 40 cycles, 1 to 30 cycles, 1 to 20 cycles, or any range between these values. In some embodiments, the number of ALD cycles is 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 220, 240, 260, 280, 300, 320, 340, 360, 380, 400, 420, 440, 460, 480, 500, or any range between these values ​​or It can be a sub-range.

[0077] After the deposition of the desired material onto the textured surface by ALD is completed, the textured surface may be heated to a temperature of about 200°C to 1000°C, 200°C to 900°C, 200°C to 800°C, 200°C to 700°C, 200°C to 600°C, 200°C to 500°C, 400°C to 800°C, or any range between these values. In some embodiments, after depositing a desired material onto a textured surface by ALD, the textured surface may be heated to a temperature of about 200 ℃, 250 ℃, 300 ℃, 350 ℃, 400 ℃, 450 ℃, 500 ℃, 550 ℃, 600 ℃, 650 ℃, 700 ℃, 750 ℃, 800 ℃, 850 ℃, 900 ℃, 950 ℃, 1000 ℃, or any range or sub-range between these values. Heating may be carried out for about 1 to 12 hours, 1 to 11 hours, 1 to 10 hours, 1 to 9 hours, 1 to 8 hours, 1 to 7 hours, 1 to 6 hours, 1 to 5 hours, 1 to 4 hours, 1 to 3 hours, 1 to 2 hours, 2 to 6 hours, 3 to 5 hours, or any range between these values. In some embodiments, heating may be carried out for about 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, or any range or sub-range between these values.

[0078] In some embodiments, after ALD treatment, the feature may exhibit shrinkage of about 1% to 15%, 1% to 4%, 1% to 13%, 1% to 12%, 1% to 11%, 1% to 10%, 1% to 9%, 1% to 8%, 1% to 7%, 1% to 6%, 1% to 5%, 1% to 4%, or 1% to 3%. In some embodiments, after ALD treatment, the feature may exhibit shrinkage of 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, or any range or sub-range between these values. In some embodiments, after ALD treatment, the structure may be annealed through exposure to electromagnetic radiation. Electromagnetic radiation may be delivered through microwave irradiation, visible light irradiation, infrared irradiation, and ultraviolet irradiation. In embodiments where electromagnetic radiation is used in annealing, the light source may be constant, or the electromagnetic radiation may be delivered through a pulsed light source that delivers concentrated pulses of light.

[0079] In some embodiments, after ALD treatment, the feature may exhibit a refractive index of about 1.2 to 4.0, 1.2 to 3.8, 1.2 to 3.6, 1.2 to 3.4, 1.2 to 3.2, 1.2 to 3.0, 1.2 to 2.8, 1.2 to 2.6, 1.2 to 2.4, 1.2 to 2.2, 1.2 to 2.0, 1.2 to 1.8, 1.2 to 1.6, 1.2 to 1.4, or any range or sub-range between these values. In some embodiments, after ALD treatment, the feature may exhibit a refractive index of approximately 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, or any range or sub-range between these values. In some embodiments, ALD may be used to create a gradient of refractive index values. Such a gradient may result from forming a shell of ALD-deposited material on or around the formed feature.

[0080] In some embodiments, the ALD treatment described herein can fill pores within the feature described herein and minimize shrinkage of the printed or transferred feature during subsequent processing, annealing, or both. In some embodiments, ALD fills pores within the feature with TiO2. In some embodiments, after the feature is heated to a temperature of about 200 °C to 1000 °C or after the feature is exposed to light, the feature has a shrinkage of about 1 to 15%. In some embodiments, after the feature is heated to a temperature of about 200 °C to 1000 °C or after the feature is exposed to light, the feature has a refractive index of about 1.2 to 4.0.

[0081] When filling the pores with ALD, the refractive index of the article may be adjusted or tuned. In some embodiments, tuning or adjustment using ALD may be used to correct errors during manufacturing, for example, to make the refractive index a desired value that does not exist in the formed article.

[0082] However, the ALD process can also be used to tune the refractive index value within an intentionally formed article to have a refractive index value below a predetermined and desired refractive index. Imprinting alone may not accurately achieve the predetermined refractive index value. However, the accurate predetermined refractive index value can be achieved by using imprinting to achieve an article having a refractive index value within about 10%, or about 9%, 8%, 7%, or about 6% of the predetermined refractive index value. Subsequently, using ALD, the refractive index value can be fine-tuned to within about 5%, 4%, 3%, 2%, 1%, 0.5%, 0.05%, or about 0.01% of the predetermined value or to the predetermined value.

[0083] ALD can fine-tune the refractive index of an article by reducing its porosity. In some embodiments, porosity may result from intentionally created porosity formed during the imprinting process. In other embodiments, porosity within the article may be intentionally induced within the article, for example, nanoparticles may be functionalized with organic ligands that induce porosity within the article. Porosity may be further tuned by controlling the particle size distribution of nanoparticles in the ink, spin coating time, or through the selection and use of binders. ALD can be used to tune the refractive index by filling intentionally created pores.

[0084] Examples

[0085] Various embodiments of the present invention may be better understood by referring to the following examples provided as examples. The present invention is not limited to the embodiments given herein.

[0086] Example 1

[0087] Deposition of TiO2 on nanoparticle ink film

[0088] A film prepared with an NP-based ink by spin coating exhibits a refractive index (RI) of 1.82. The NP-based ink contained 1,2-propanediol, methanol, isopropanol, and titanium diisopropoxide bis(acetylacetonate). After heating to 250 °C, the film exhibits a refractive index of approximately 1.86. After 25 deposition cycles, the film exhibits an RI of 2.25. The lateral shrinkage of a TiO2 film coated with TiO2NP ink and a TiO2-coated film prepared using an NP-based ink and subsequently having TiO2 deposited in the pores by ALD was compared after heating to 475 °C for 4 hours. The film without ALD treatment exhibited 18.8% shrinkage, whereas the ALD-treated films exhibited 6.8% and 3.7% shrinkage during 25 and 150 cycles, respectively. Porosity can be calculated from the refractive index. The film without ALD treatment showed porosity of 31.1% and 28.1% before and after heating to 475 °C for 4 hours, respectively, whereas the film that underwent 25 cycles of ALD showed porosity of 9.0% and 6.9% before and after heating to 475 °C for 4 hours, respectively.

[0089] To reduce porosity with a slightly increased RI compared to that achieved with TiO2, a material having a low intrinsic RI, such as SiO2, can be deposited into the pores. Using a material like SiO2 provides a method for tuning different RI values.

[0090] [Table 1]

[0091] Expected layer thickness according to the number of ALD cycles for the deposition of TiO2 on a nanoparticle ink film

[0092]

[0093] A comparison of the refractive indices of the substrates with and without ALD of TiO2 was examined, where ALD was performed at 250 °C on exposed (bare) Si and spin-coated TiO2 nanoparticle films. Unexpectedly, in the ALD of a 1.4 nm-thick layer of TiO2, the refractive index increased significantly from 1.82 to 2.25. Numerical data associated with the experiment are listed in Table 2. The literature refractive index value for anatase is 2.488.

[0094] [Table 2]

[0095] Comparison of refractive index of TiO2 with and without ALD, according to the number of ALD cycles (n D ).

[0096]

[0097] Tables 3 and 4 show data related to the change in the percentage of the refractive index of the substrate after ALD of TiO2.

[0098] [Table 3]

[0099] Comparison of refractive index according to the number of ALD cycles with and without ALD of TiO2 after sample treatment at 475 ℃ for 4 hours (n D ).

[0100]

[0101] [Table 4]

[0102] Comparison of percentage shrinkage of TiO2 with and without ALD, according to the number of ALD cycles, after treatment of samples at 475 ℃ for 4 hours.

[0103]

[0104] ALD treatment can reduce the porosity of the nanoparticle ink films or features described herein. The Lorentz-Lorentz equation can calculate porosity using the pores, bulk material, and refractive index values ​​of the film. Porosity (air voids) reduces the refractive index of the film (n air =1). Although all films have a certain amount of residual porosity, ALD-treated films and features as described herein have significantly smaller porosity. Heat treatment results in a smaller change in porosity in ALD-treated samples compared to NP-unique (nanofine particle) samples.

[0105] [Table 5]

[0106] Comparison of changes in porosity according to the ALD cycle. The sample was heated to 475 °C and maintained at that temperature for 4 hours.

[0107]

[0108] Example 2

[0109] Materials. 20 wt% TiO2NP in 1,2-propanediol was purchased from Research Nanomaterials Inc., USA. The TiO2 precursor, tetrakis(dimethylamino)titanium (TDMAT), and the aluminum oxide (Al2O3) precursor, trimethylaluminum (TMA), were purchased from Cambridge NanoTech. 75% titanium diisopropoxide bis(acetylacetonate) and 99% photoinitiator 2,2-dimethoxy-2-phenylacetophenone (DMPA) in isopropanol were purchased from Sigma Aldrich. Sylgard 184 (polydimethylsiloxane, PDMS) was purchased from Ellsworth Adhesives. Trimethylsiloxy-terminated (7.0 to 8.0% vinylmethylsiloxane)-dimethylsiloxane copolymer (VS), platinum-divinyltetramethyldisiloxane complex in xylene (Pt-DVS), and hydride-terminated (25 to 30% methylhydrosiloxane)-dimethylsiloxane copolymer (MCP) were purchased from Gelest. 2,4,5,8-tetramethyl-2,4,6,8-tetravinylcyclotetrasiloxane (TCS) was purchased from Fluka. Norland Optical Adhesive 60 (NOA60) was purchased from Norland Products Inc. Methanol and isopropanol were purchased from Fischer Scientific. Fluorolink MD700, a perfluorinated diacrylate, was purchased from Cornerstone Technology, LLC. ST505 PET web was purchased from Tekra. The silicon substrate was purchased from Nova Electronics. The quartz substrate was purchased from ChemGlass. All materials were used without further purification.

[0110] Method. A nanoparticle dispersion was prepared by diluting raw material TiO2 nanoparticles with methanol from 20 wt% to between 2.5 and 10 wt%. Subsequently, the dispersion was sonicated for 5 minutes. After sonication, 10% titanium diisopropoxide bis(acetylacetonate) or tetraethyl orthosilicate (TEOS) was added to the dispersion (10% solid relative to the mass of TiO2NP), and the dispersion was sonicated again for 5 minutes.

[0111] Before fabricating planar or patterned films, the silicon substrate was exposed to an oxygen plasma for 5 minutes to activate the surface. The planar film was spin-coated at 3000 rpm until all solvent was removed. Patterned structures were fabricated. Briefly, a PDMS prepolymer was poured onto silicon fluoride containing various nanopatterns to prepare a stamp. After curing, the PDMS stamp can be easily removed and used and reused in solvent-assisted NILs. A diluted TiO2 dispersion was spin-coated at 3000 rpm for 5 to 30 seconds under 5% RH, followed by carefully placing the PDMS stamp on the top of the film. After a few minutes on a 50 °C hotplate, the PDMS stamp was removed to expose the imprinted TiO2.

[0112] For high aspect ratio (HAR) pillars, a modified approach was adopted. A silicon fluoride master containing HAR vias was spin-coated with a Fluorolink MD700 prepolymer containing 2% DMPA (relative to prepolymer weight) and subsequently placed face down onto a cured PET NOA60-coated piece. The entire assembly was placed in a Nanonex imprinting tool (NX-2600BA), vacuum-pumped for 2 minutes, followed by imprinting and UV-curing at 10 psi for 15 minutes. After separation, a fluoropolymer replication mold containing the pillars was bonded to a Si wafer with a layer of NOA60 using Nanonex to secure a flat and smooth surface. To improve the transfer of HAR features from these HAR patterns, a composite PDMS stamp was prepared. Briefly, the fabrication of the composite stamp involves mixing VS, TCS, Pt-DVS, and MCP in appropriate amounts, spin-coating the layer onto a replica master, curing on a hot plate, and then backing with Sylgard 184. After curing, TiO2NP-based ink was imprinted using an HPDMS stamp. The imprinted HAR filament features were exposed to NIR irradiation through the stamp (Adphos 126-125 NIR dryer) prior to separation.

[0113] The films and structures were exposed to a large number of deposition cycles in a Cambridge NanoTech Savannah 90 atomic layer deposition system. Unless otherwise specified, all depositions were performed at 250 °C. The subsequent TiO2 deposition recipe consisted of a 0.1 second TDMAT pulse followed by a 0.015 second H2O pulse, with an expected growth rate of approximately 0.4 Å / cycle. Similarly, Al2O3 deposition was performed with a 0.015 second H2O pulse followed by a 0.015 second TMA pulse, corresponding to a growth rate of approximately 1 Å / cycle.

[0115] *Characterization. The refractive index and film thickness of the planar film, as well as the transmittance and reflection intensities, were measured using variable-angle spectroscopic polarization on a JA Woollam RC2 ellipsometer. The polarization data were modeled using a Cauchy model for the transparent region of TiO2, and a b-spline model with Kramers-Kronig compatibility was used to include the absorption region (UV).

[0116] Films and nanostructures were analyzed from top to bottom and cross-sectionally using a scanning electron microscope with an FEI Magellan 400 FESEM. Surface roughness was measured using an atomic force microscope (Veeco Dimension 3100). The composition as a function of film depth was characterized by X-ray photoelectron microscopy (XPS) using a Quantum 2000 Scanning ESCA microprobe (Physical Electronics, Inc.) with Al-Kα radiation (1486.6 eV).

[0117] ALD on flat film

[0118] Both NP-based films and nanostructures were densified using ALD. Nanostructures and thin films were prepared by spin-coating NP dispersions onto a Si substrate, imprinted, or completely dried prior to ALD. In each ALD treatment, as a reference, a sample was deposited onto an NP-based film and an exposed silicon phase.

[0119] Table 6 shows the expected thicknesses for different depositions on the exposed Si, which were calculated based on a growth rate of 0.4 Å / cycle provided by Cambridge NanoTech. Both the measured refractive index and thickness are in good agreement with the expected results. A decrease in refractive index with the number of cycles is expected, which is attributed to the formation of discontinuous films at fewer deposition cycles. The NP films were characterized before and after each ALD treatment.

[0120] [Table 6]

[0121] TiO2 deposition on exposed Si

[0122]

[0123] The thickness and refractive index of the planar TiO2NP film were measured after spin coating and after heat treatment at 250 °C, as control after deposition is performed at 250 °C. After heat treatment at 250 °C for 2 hours, the refractive index of the as-spun film increased from 1.82 to 1.86, and the film thickness decreased from 48 nm to 44 nm. These slight changes may be due to the slight densification of the NP film. To determine the effect of ALD on the TiO2NP film, several thin films were prepared from the aforementioned NP dispersion and exposed to various numbers of ALD cycles.

[0124] After 380 ALD cycles, the measured total film thickness is 72 nm and the refractive index is 2.26; however, after only 25 cycles, a negligible change in film thickness occurs, accompanied by an increase of approximately 24% in the refractive index. The total refractive index as a function of wavelength for 50 ALD cycles highlights the rapid, near-bulk value that can be achieved by short ALD process steps. Such results suggest that the intrinsic porosity of the NP film is reduced by ALD, which can also be observed from changes in the film surface morphology with increasing ALD cycles. Using the Lorentz-Lorentz equation, the porosity of the NP film was calculated after spinning, before and after 0, 25, 50, 150, and 380 ALD cycles, as shown in Table 7.

[0125] [Table 7]

[0126] Porosity calculated using the Lorentz-Lorentz equation.

[0127]

[0128] The NP film without ALD treatment resulted in a porosity of approximately 30%, which is (n of bulk TiO2 DThis is the cause of the relatively small refractive index value of 1.82 (compared to 2.488). After heating, the porosity of the untreated sample decreases, but still approaches 30%. However, after 50 ALD cycles on the NP film, a significant reduction in porosity exceeding 20% ​​was observed, which corresponds to an increase in refractive index. Furthermore, after heating these samples, the porosity decreases by only 1.6% compared to 3% for the untreated sample. These results suggest that 25 to 50 ALD cycles are an effective method for reducing film porosity, which leads to an improvement in the refractive index value of the film. A reduction in pore volume, or porosity, advantageously results in a reduction in shrinkage upon heating. In addition, the surface roughness (rms) of the NP film before ALD was 2.1 ± 0.1 nm and did not change significantly after ALD, which is an important consideration in optical applications, as undesirable scattering would be detrimental to performance.

[0129] ALD on patterned surfaces

[0130] Unlike planar films where the refractive index can be reliably measured, verifying deposition by ALD into the pores of a patterned surface requires a different technique. To verify deposition into the pores using ALD, aluminum oxide (Al2O3) was deposited onto a TiO2 grating, and the presence of oxygen, aluminum, and titanium was observed throughout the grating using EDS. In this example, to achieve a fundamental contrast between the imprinted particles and the ALD-deposited material, 100 cycles of Al2O3, corresponding to approximately 10 nm, were deposited into the imprinted lines.

[0131] After deposition, changes in feature size and surface texture were observed to confirm the deposition of Al2O3 by ALD. EDS indicated the presence of oxygen throughout the grating, which was expected as oxygen is a component of both TiO2 and Al2O3. The presence of aluminum showed a gradient; aluminum is concentrated at the edges of the grating and its concentration decreases in the interior. The opposite was observed for titanium, consequently indicating that titanium is concentrated in the interior of the grating. These findings are consistent with expected results: Al2O3 is deposited first inside the nanoparticle pores, followed by conformal deposition on the outer side of the grating. With this confirmation, the patterned TiO2NP-based structures were densified with TiO2 by ALD.

[0132] In some photonic and metasurface applications, patterned structures with an AR greater than 1 were generated. The pillars were created by direct patterning, do not require etching or resist removal steps, and can be scaled to wafer-based production. In contrast, for suitable line grating, HAR pillars require an annealing treatment via the stamp prior to stamp removal to promote sufficient bonding between NPs so that the pillars are not destroyed during stamp removal. After placing the PDMS stamp on the NP film, the solvent was dried on a hot plate, and then the substrate-stamp assembly was exposed to NIR irradiation for 20 seconds.

[0133] Such pillars can be effectively patterned over a large area. To compare the variation in feature dimensions from the master and NP imprints, the UV-curable polymer NOA60 was imprinted. In a HAR pillar section on the silicon master, the diameter of the imprinted NOA60 pillar was measured to be 140 ± 5 nm at the top of the pillar and the height to be 1.1 µm, resulting in a HAR of 7.9. However, the imprinted TiO2 from the same section was measured to have a diameter of 130 ± 4 nm and a height of 815 nm, resulting in a HAR of 6.3. Compared to the NOA imprint, the shrinkage of the measured diameter of the NP pillar relative to the master is less than 10%, while the shrinkage of the height is 26%. Such shrinkage is caused by the solvent-assisted imprint technique; Solvent-dispersed NPs fill the PDMS stamp by capillary force, and then the solvent diffuses through the stamp, resulting in a mold volume that is not completely filled. To achieve specific imprinted feature dimensions, a master mold can be manufactured to include shrinkage compensation.

[0134] The HAR TiO2 pillars as they are imprinted show the same pillar area after 50 cycles of TiO2ALD. No apparent changes were observed within the structure, indicating that the deposited TiO2 is not simply deposited on the surface. One change observed between the HAR pillars before and after ALD is a slight increase in HAR after ALD, which is likely due to slight shrinkage from heating (250 °C) during ALD.

[0135] Tunability of all-inorganic TiO2 films

[0136] While achieving the highest possible refractive index is required in many applications, the ability to tune the refractive index over a range of values ​​can be utilized in situations requiring precise index tailoring, matching, and / or grading. The film was fabricated by spin-coating a TiO2NP film for 5 seconds and then further drying it on a 60°C hot plate for 2 minutes, conditions similar to those used to generate nanopatterns via solvent-assisted NIL. It should be noted that this results in a slightly smaller starting refractive index value (0 cycles ALD). This is attributed to differences in NP packing; the spin-coated film up to complete solvent removal is more densely packed and has a slightly larger value (1.82 vs. 1.77). Refractive index (n D The value increases linearly with the number of ALD cycles from 2 to 15, which can approach an intermediate refractive index value that can be used to manufacture gradient refractive index (GRIN) lenses. This tunable method has the advantage of being entirely inorganic and composed of a single material. All-inorganic materials may be desirable in many applications involving durability and UV stability. Additionally, by using only TiO2, compatibility between the two materials is ensured.

[0137] The terms and expressions used herein are used in connection with the description and are non-limiting, and in the use of such terms and expressions, there is no intention to exclude any equivalents of the features (or parts thereof) shown and described, and it should be recognized that various modifications may be made within the scope of the embodiments of the present invention. Accordingly, although the present invention has been specifically disclosed by particular embodiments, it should be understood that optional features, modifications, and changes to the concepts disclosed herein may be made by those skilled in the art, and that such modifications and changes are considered to be included within the scope of the embodiments of the present invention.

[0138] Enumerated implementation examples.

[0139] The following exemplary embodiments are provided, and the numbers are not to be interpreted as indicating the level of importance.

[0140] Embodiment 1 provides a method for manufacturing a textured surface, and such a method comprises:

[0141] Step of placing a template on a substrate; and

[0142] It includes a step of flattening the template with nanoparticle ink.

[0143] Embodiment 2 provides the method of Embodiment 1 and further includes the step of imprinting a mold with a mold comprising a plurality of features that penetrate the mold to form an imprinted mold.

[0144] Embodiment 3 provides any one of Embodiments 1 or 2, and the template comprises a cross-linked material.

[0145] Embodiment 4 provides any one of the methods of Embodiments 1 to 3, and the mold comprises a polymer resin.

[0146] Embodiment 5 provides the method of Embodiment 2, and the imprinting step includes residue-free imprint lithography.

[0147] Embodiment 6 provides the method of Embodiment 2, and the imprinting step creates an imprinted feature in a template that substantially corresponds to a feature on the mold in shape and position.

[0148] Embodiment 7 provides the method of Embodiment 6, and the nanoparticle ink substantially fills the imprinted features within the template.

[0149] Embodiment 8 provides any one of the methods of Embodiments 1 to 8, and the nanoparticle ink comprises indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0150] Embodiment 9 provides any one of embodiments 1 to 9, and the method further includes the step of first annealing an imprinted template and a substrate.

[0151] Embodiment 10 provides the method of Embodiment 8, and the first annealing step includes heating, microwave irradiation, visible light irradiation, infrared irradiation, and ultraviolet irradiation.

[0152] Embodiment 11 provides any one of Embodiments 1 to 10 and further includes the step of removing a template from a substrate.

[0153] Embodiment 12 provides the method of Embodiment 11, and the removal step includes dissolution, calcination, or irradiation using microwave irradiation, visible light irradiation, infrared irradiation, and ultraviolet irradiation.

[0154] Embodiment 13 provides the method of Embodiment 12 and further includes the step of second annealing of the substrate and the template.

[0155] Embodiment 14 provides any one of Embodiments 2 to 13, and the feature has a height:width aspect ratio of about 2:1 to about 10:1.

[0156] Embodiment 15 provides any one of Embodiments 2 to 14, and the features are arranged in a periodic pattern.

[0157] Embodiment 16 provides any one of Embodiments 2 to 15, and features are arranged randomly.

[0158] Embodiment 17 provides any one of embodiments 2 to 16, and a mold comprising at least one substantially flat surface and at least one of a feature has a side that forms an acute angle with the mold.

[0159] Embodiment 18 provides the method of Embodiment 17, wherein the acute angle is in the range of about 10 degrees to about 89 degrees.

[0160] Embodiment 19 provides a method for manufacturing a textured surface, and such a method comprises:

[0161] A step of flattening an imprinted template with nanoparticle ink to form a transfer print master; and

[0162] It includes the step of bringing the transfer print master into contact with the substrate.

[0163] Embodiment 20 provides the method of Embodiment 19, and

[0164] A step of placing a template on a first substrate prior to flattening; and

[0165] The method further includes the step of imprinting a mold with a mold comprising a plurality of features that penetrate the mold to form an imprinted mold.

[0166] Embodiment 21 provides the method of Embodiment 19 or 20 and further includes the step of removing a transfer print master to provide a plurality of features placed on a second substrate.

[0167] Embodiment 22 provides any one of the methods of Embodiments 19 to 21, and the surface of the mold plate includes a hard coating.

[0168] Embodiment 23 provides the method of Embodiment 20, and the imprinted template comprises a cross-linked material.

[0169] Embodiment 24 provides any one of the methods of Embodiments 19 to 23, and the mold comprises a polymer resin.

[0170] Embodiment 25 provides any one of Embodiments 20 to 24, and the imprinting step includes residue-free imprint lithography.

[0171] Embodiment 26 provides any one of embodiments 20 to 25, and the imprinting step creates an imprinted feature in an imprinted template whose shape and position substantially correspond to a feature on the mold.

[0172] Embodiment 27 provides the method of Embodiment 26, wherein the nanoparticle ink substantially fills the imprinted features within the imprinted template.

[0173] Embodiment 28 provides any one of the methods of Embodiments 19 to 27, and the nanoparticle ink comprises indium tin oxide (ITO), titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0174] Embodiment 29 provides any one of embodiments 19 to 28, and the method further includes the step of annealing a substrate and a template.

[0175] Embodiment 30 provides the method of Embodiment 29, and the annealing step includes heating, microwave irradiation, visible light irradiation, infrared irradiation, and ultraviolet irradiation.

[0176] Embodiment 31 provides any one of Embodiments 19 to 30, and the contacting step includes a sheet-based or roll-to-roll transfer process.

[0177] Embodiment 32 provides any one of Embodiments 21 to 31, and the removal step includes dissolution, calcination, or irradiation using microwave irradiation, visible light, infrared light, and ultraviolet light.

[0178] Embodiment 33 provides an article comprising a textured surface formed by any one of the methods of Embodiments 1 to 32.

[0179] Embodiment 34 provides an article of Embodiment 33, and the article includes a lens, a flat lens, a display, a flexible display, a touch panel, a sensor surface, a shielding foil, or a blaze grating.

[0180] Embodiment 35 provides an article comprising a textured surface formed by any one of the methods of Embodiments 19 to 34.

[0182] * Embodiment 36 provides an article of Embodiment 35, and the article includes a lens, a flat lens, a display, a flexible display, a touch panel, a sensor surface, a shielding foil, or a blaze grating.

[0183] Embodiment 37 provides a method for manufacturing a textured surface, and such a method comprises:

[0184] Step of placing the template on the substrate;

[0185] A step of imprinting a mold with a mold comprising a plurality of features penetrating the mold to form an imprinted mold;

[0186] A step of flattening an imprinted template with nanoparticle ink;

[0187] Step of annealing nanoparticle ink; and

[0188] Includes a step of removing an imprinted template;

[0189] The imprinting step generates an imprinted feature within a template that substantially corresponds in shape and position to a feature on the mold;

[0190] The nanoparticle ink substantially fills the imprinted features within the template; and

[0191] Nanoparticle inks include indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0192] Embodiment 38 provides a method for manufacturing a textured surface, and such a method comprises:

[0193] A step of placing a template on a first substrate;

[0194] A step of imprinting a mold with a mold comprising a plurality of features penetrating the mold to form an imprinted mold;

[0195] A step of flattening an imprinted template with nanoparticle ink to form a transfer print master;

[0196] Step of annealing nanoparticle ink;

[0197] A step of bringing the transfer print master into contact with a second substrate; and

[0198] The method includes the step of removing a transfer print master to provide a plurality of features placed on a second substrate;

[0199] The imprinting step generates an imprinted feature within a template that substantially corresponds in shape and position to a feature on the mold;

[0200] The nanoparticle ink substantially fills the imprinted features within the template; and

[0201] Nanoparticle inks include indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof.

[0202] Embodiment 39 provides the method of Embodiment 38:

[0203] The method further comprises the step of performing at least one cycle of atomic layer deposition (ALD) on an imprinted feature, wherein the ALD deposits a first reactant and a second reactant;

[0204] The first reactant is MX y , MR y , M(NR) y , M(OR) y , MX y R z , MX y (NR) z , MX y (OR) z Includes , MCp2, or a combination thereof;

[0205] The second reactant contains water;

[0206] Here, each y and z is independently an integer from 2 to 8;

[0207] M is a metal;

[0208] Each X is independently F, Cl, Br, or I;

[0209] Each R is independently hydrogen or substituted or unsubstituted C 1-20 It is alkyl; and

[0210] Cp is a substituted or unsubstituted cyclopentadienyl.

[0211] Embodiment 40 provides the method of Embodiment 20:

[0212] The method further comprises the step of performing at least one cycle of atomic layer deposition (ALD) on an imprinted feature, wherein the ALD deposits a first reactant and a second reactant;

[0213] The first reactant is MX y , MR y , M(NR) y , M(OR) y , MX y Rz , MX y (NR) z , MX y (OR) z Includes , MCp2, or a combination thereof;

[0214] The second reactant contains water;

[0215] Here, each y and z is independently an integer from 2 to 8;

[0216] M is a metal;

[0217] Each X is independently F, Cl, Br, or I;

[0218] Each R is independently hydrogen or substituted or unsubstituted C 1-20 It is alkyl; and

[0219] Cp is a substituted or unsubstituted cyclopentadienyl.

[0220] Embodiment 41 provides the method of Embodiment 40, and ALD fills the small pores within the feature with TiO2.

[0221] Embodiment 42 provides the method of Embodiment 41, and after the feature is heated to a temperature of about 200°C to 1000°C or after the feature is exposed to light, the feature has a shrinkage of about 1 to 15%.

[0222] Embodiment 43 provides the method of Embodiment 42, and after the feature is heated to a temperature of about 200 ℃ to 1000 ℃ or after the feature is exposed to light, the feature has a refractive index of about 1.2 to 4.0.

[0223] Example 44 provides an article, and the article is:

[0224] It includes a surface in which multiple features protrude, and

[0225] The feature has a height:width aspect ratio of about 2:1 to about 10:1.

[0226] Embodiment 45 provides the article of Embodiment 44, and the features are arranged in a periodic pattern.

[0227] Embodiment 46 provides any one of Embodiments 44 or 45, and features are arranged randomly.

[0228] Embodiment 47 provides any one of embodiments 44 to 46, and at least one of the features has a side that forms an acute angle with the surface.

[0229] Embodiment 48 provides the article of Embodiment 47, and the acute angle is in the range of about 10 degrees to about 89 degrees.

[0230] Embodiment 49 provides any one of embodiments 44 to 48, and the features independently have a refractive index of about 1.2 to 4.0.

[0231] Embodiment 50 provides an article of Embodiment 49, wherein after the features are heated to a temperature of about 200°C to 1000°C or after the features are exposed to light, the features independently have a refractive index of about 1.2 to about 4.0.

[0232] Embodiment 51 provides any one of embodiments 44 to 50, and the article comprises a lens, a display, a flexible display, a touch panel, a sensor surface, a shielding foil, a meta-lens, an optical field display, a flat lens, or a blaze grating.

[0233] Embodiment 52 provides any one of Embodiments 44 to 51, and the article is optically transparent.

[0234] Embodiment 53 provides an article of Embodiment 52, and the article is optically transparent to electromagnetic radiation in the range of about 400 nm to about 1400 nm.

[0235] Embodiment 54 provides any one of Embodiments 52 or 53, and the article is optically transparent to electromagnetic radiation in the range of about 400 nm to about 700 nm.

[0236] Embodiment 55 provides any one of Embodiments 52 to 54, and the article is optically transparent to electromagnetic radiation greater than 905 nm.

[0237] Embodiment 56 provides any one of Embodiments 44 to 55, and the article is a virtual reality or augmented reality device.

[0238] Embodiment 57 provides any one of Embodiments 44 to 56, and the article is a meta-lens or a flat lens.

[0239] Embodiment 58 provides a method for manufacturing a textured surface, and such a method comprises:

[0240] Step of placing a nanoparticle-based ink on a substrate;

[0241] A step of imprinting ink into a mold including a plurality of features to obtain a textured surface,

[0242] A step of performing at least one cycle of atomic layer deposition (ALD) on a textured surface, wherein the ALD includes depositing a first reactant and a second reactant;

[0243] The first reactant is MX y , MR y , M(NR) y , M(OR) y , MX y R z , MX y (NR) z , MX y (OR) z Includes , MCp2, or a combination thereof;

[0244] The imprinting step creates an imprinted feature on a substrate, wherein the feature substantially corresponds in shape and position to a feature on the mold;

[0245] The nanoparticle ink substantially fills the features within the mold to create the features;

[0246] The nanoparticle ink comprises indium tin oxide, titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof;

[0247] The second reactant includes water;

[0248] Each y and z is independently an integer from 2 to 8;

[0249] M is a metal;

[0250] Each X is independently F, Cl, Br, or I;

[0251] Each R is independently hydrogen or substituted or unsubstituted C 1-20 It is alkyl; and

[0252] Cp is a substituted or unsubstituted cyclopentadienyl.

[0253] Embodiment 59 provides an article formed according to the method of Embodiment 58.

[0254] Embodiment 60 provides any one of Embodiments 58 or 59, and the article is:

[0255] It includes a surface in which multiple features protrude, and

[0256] The feature has a height:width aspect ratio of about 2:1 to about 10:1.

[0257] Embodiment 61 provides an article of Embodiment 60, and the features are arranged in a periodic pattern.

[0258] Embodiment 62 provides the article of Embodiment 60, and the features are arranged randomly.

[0259] Embodiment 63 provides any one of embodiments 60 to 62, and at least one of the features has a side that forms an acute angle with the surface.

[0260] Embodiment 64 provides the article of Embodiment 63, and the acute angle is in the range of about 10 degrees to about 89 degrees.

[0261] Embodiment 65 provides an article of Embodiment 64, wherein the features independently have a refractive index of about 1.2 to 4.0.

[0262] Embodiment 66 provides an article of Embodiment 65, wherein after the features are heated to a temperature of about 200°C to 1000°C or after the features are exposed to light, the features independently have a refractive index of about 1.2 to about 4.0.

[0263] Embodiment 67 provides the article of Embodiment 66, and the refractive index corresponds to a predetermined refractive index value.

[0264] Embodiment 68 provides the article of Embodiment 67, and the refractive index is within 5 percent of a predetermined refractive index value.

[0265] Embodiment 69 provides any one of embodiments 60 to 68, and the article comprises a lens, a display, a flexible display, a touch panel, a sensor surface, a shielding foil, a meta-lens, an optical field display, a flat lens, or a blaze grating.

[0266] Embodiment 70 provides any one of Embodiments 60 to 69, and the article is optically transparent.

[0267] Embodiment 71 provides an article of any one of embodiments 60 to 70, and the article has a gradient of refractive index values.

Claims

Claim 1 A method for manufacturing a textured surface comprising: a step of placing a nanoparticle-based ink on a substrate; a step of imprinting the ink with a mold having a plurality of features to form a textured nanoparticle-based ink; and a step of performing at least one cycle of atomic layer deposition (ALD) on the textured nanoparticle-based ink to fill pores in the textured nanoparticle-based ink and form a textured surface, wherein the ALD is MX y , MR y , M(R) y , M(NR) y , M(OR) y , MX y R z , MX y (R) z , MX y (NR) z , MX y (OR) z The method comprises the step of sequentially depositing a first reactant comprising MCp2, or a combination thereof, and a second reactant; wherein each y and z are independently integers from 2 to 8; M is a metal; each X is independently F, Cl, Br, or I; and each R is independently hydrogen or substituted or unsubstituted C 1-20 A method in which alkyl is; and Cp is a substituted or unsubstituted cyclopentadienyl. Claim 2 A method according to claim 1, wherein the second reactant comprises water, oxygen, or ozone. Claim 3 In claim 1, the textured surface is substantially free of organic material. Claim 4 A method according to claim 1, further comprising the step of treating the nanoparticle-based ink by exposure to electromagnetic radiation or by heating after at least one cycle of ALD. Claim 5 A method according to claim 4, wherein the features of the transferred pattern have a shrinkage of 1% to 15% after the textured surface is exposed to heating or electromagnetic radiation. Claim 6 A method according to claim 1, wherein the nanoparticle-based ink comprises nanoparticles comprising indium tin oxide (ITO), titanium dioxide, aluminum oxide, silicon dioxide, metal oxide, metal nitride, metal carbide, metal oxynitride, metal oxycarbide, metal boride, metal silicide, or a combination thereof. Claim 7 A method according to claim 1, further comprising the step of performing a plurality of cycles of ALD. Claim 8 A method according to claim 1, comprising the step of using one or more cycles of ALD to adjust the refractive index of a textured surface to a desired value. Claim 9 In paragraph 4, one or more cycles of ALD during electromagnetic radiation or heating reduce shrinkage of the textured surface. Claim 10 The method according to claim 1, wherein the textured surface comprises a lens, a display, a flexible display, a touch panel, a sensor surface, a shielding foil, a meta-lens, an optical field display, a flat lens, a blaze grating, a virtual reality device, or an augmented reality device. Claim 11 A method for manufacturing a textured surface comprising: a step of placing a template having a patterned surface on a substrate and flattening the template with a nanoparticle ink to form a textured nanoparticle ink having a pattern of features corresponding to the patterned surface of the template; and a step of performing at least one cycle of atomic layer deposition (ALD) on a textured nanoparticle-based ink to fill pores in the textured nanoparticle-based ink and form a textured surface, wherein the ALD is MX y , MR y , M(R) y , M(NR) y , M(OR) y , MX y R z , MX y (R) z , MX y (NR) z , MX y (OR) z The method comprises the step of sequentially depositing a first reactant comprising MCp2, or a combination thereof, and a second reactant; wherein each y and z are independently integers from 2 to 8; M is a metal; each X is independently F, Cl, Br, or I; and each R is independently hydrogen or substituted or unsubstituted C 1-20 A method in which alkyl is; and Cp is a substituted or unsubstituted cyclopentadienyl. Claim 12 In paragraph 11, the textured surface is substantially free of organic material, a method. Claim 13 In claim 11, the textured surface comprises a lens, a display, a flexible display, a touch panel, a sensor surface, a shielding foil, a meta-lens, an optical field display, a flat lens, a blaze grating, a virtual reality device, or an augmented reality device. Claim 14 An article comprising: a textured atomic layer deposition treated surface including a plurality of features, wherein the plurality of features protrude from the textured atomic layer deposition treated surface and are arranged in a periodic pattern or randomly arranged, and the textured surface comprises a textured atomic layer deposition treated surface that is optically transparent to visible light, and the pores of the atomic layer deposition treated surface are MX y , MR y , M(NR) y , M(R) y , M(OR) y , MX y R z , MX y (R) z , MX y (NR) z , MX y (OR) z The reaction product of an atomic layer deposition reaction of a first reactant comprising , MCp2, or a combination thereof, and a second reactant, wherein each y and z are independently integers from 2 to 8; M is a metal; each X is independently F, Cl, Br, or I; and each R is independently hydrogen or substituted or unsubstituted C 1-20 Articles in which alkyl is; and Cp is a substituted or unsubstituted cyclopentadieneyl. Claim 15 In paragraph 14, the pore is an article containing at least two layers of the product of the first reactant and the second reactant. Claim 16 In paragraph 14, the textured atomic layer deposition treated surface is substantially free of organic material, an article. Claim 17 In paragraph 14, the second reactant is an article containing water, oxygen, or ozone. Claim 18 Article 14, wherein the features independently have a height:width aspect ratio of 2:1 to 10:

1. Claim 19 Article 14, wherein the textured surface is optically transparent to visible light and / or optically transparent to electromagnetic radiation in the range of 400 nm to 1400 nm. Claim 20 In paragraph 14, the article comprises a lens, a display, a flexible display, a touch panel, a sensor surface, a shielding foil, a meta-lens, an optical field display, a flat lens, a blaze grating, a virtual reality device, or an augmented reality device.

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