KR101616178B1 - Method of manufacturing a solar thermal absorber - Google Patents

Abstract

A method of manufacturing a solar absorber, comprising: forming a metal layer and a first nanostructure having a first conductive nanopattern on the metal layer; On the other hand, a sacrificial layer and a second nanostructure having a second conductive nanopattern are formed on the sacrificial layer. Next, the second nanostructure is bonded on the first nanostructure so that the first and second conductive nanopatterns face each other.

Description

TECHNICAL FIELD [0001] The present invention relates to a method of manufacturing a solar absorber,

The present invention relates to a method of manufacturing a solar absorber, and more particularly, to a method of manufacturing a solar absorber that accumulates heat energy using solar heat having a broad spectrum or converts it into electrical energy.

In general, the efficiency of a solar absorber can be improved if the absorptivity to solar energy is high and the emissivity is low at its own temperature.

Various methods have been tried to satisfy this. For example, there is a technique of selectively coating the surface of an absorber with a specific material in order to increase the absorption rate of solar energy and lower the emissivity, but the coating is not stable yet and the coating is peeled off at high temperature, . On the other hand, another technique is known in which the surface roughness of the absorber is controlled to increase the absorptivity and lower the emissivity.

In particular, Korean Patent Registration No. 10-1229772 discloses a technique for controlling the surface roughness. However, in the technique of controlling the surface roughness, it is still difficult to form the absorber to have a high absorption rate in a wide wavelength band.

It is an object of the present invention to provide a method of manufacturing a solar absorber having an improved absorption rate and emissivity at a relatively wide wavelength band.

In order to accomplish the above-mentioned object of the present invention, in a method of manufacturing a solar absorber according to an embodiment of the present invention, a first nanostructure having a metal layer and a first conductive nanopattern is formed on the metal layer. On the other hand, a sacrificial layer and a second nanostructure having a second conductive nanopattern are formed on the sacrificial layer. Next, the second nanostructure is bonded onto the first nanostructure so that the first and second conductive nanopatterns face each other.

In one embodiment of the present invention, a pre-bonding layer may be additionally formed on the first nanostructure using a thermosetting resin before bonding the second nanostructure on the first nanostructure,

In order to bond the second nanostructure on the first nanostructure, the preliminary bonding layer may be thermally cured by a thermal curing process to convert into a bonding layer.

In one embodiment of the present invention, the metal layer and the dielectric layer are sequentially formed on the first substrate to form the first nanostructure. And a first undercut formation film is formed on the dielectric film. A first mask pattern is formed on the first undercut forming film through a nanoimprint lithography process. The first undercut formation film is patterned using the first mask pattern to form a first undercut formation film pattern. A first metal thin film is formed isotropically on a first substrate including the first undercut film pattern. The first undercut formation film pattern may be removed from the substrate through a lift-off process to form a first conductive nano pattern on the dielectric film.

In one embodiment of the present invention, a sacrificial film is formed on the second substrate to form the second nanostructure. And a second undercut forming film is formed on the sacrificial film. A second mask pattern is formed on the second undercut forming film through a nanoimprinting lithography process. And the second undercut formation film is patterned using the second mask pattern to form a second undercut formation film pattern. The second metal thin film is formed isotropically on the second substrate including the second undercut film pattern. The second undercut forming film pattern may be removed from the second substrate through a lift-off process to form a second conductive nano pattern on the sacrificial film.

In one embodiment of the present invention, each of the first and second conductive nanopatterns may have a bar shape extending in parallel to each other, a cross bar shape extending to cross each other, a C- Or may have an S shape to cross each other.

In one embodiment of the present invention, the sacrificial layer may use an HSQ material.

In an embodiment of the present invention, a step of removing the sacrificial layer may be further performed.

According to the above-described method of manufacturing a solar absorber, a first nanostructure including a first conductive nanopattern and a second nanostructure including a second conductive nanopattern are formed, and the first and second nanostructures are bonded to each other Thereby making it possible to easily manufacture a solar absorber in which structures in which the first and second conductive nano patterns are stacked vertically are stacked.

The first and second conductive nano patterns may be formed through a nanoimprint lithography process and a lift-off process to change shapes, sizes, materials, etc. of the first and second conductive nano patterns so that the resonance frequency The absorption rate can be improved by matching the resonance frequency to a wavelength having a relatively low absorption rate.

1 is a flowchart illustrating a method of manufacturing a solar absorber according to an embodiment of the present invention.
FIGS. 2 to 7 are cross-sectional views illustrating a method of forming the first nanostructure.
FIGS. 8 to 13 are cross-sectional views illustrating a method of forming the second nanostructure.
Figs. 14 to 16 are cross-sectional views for explaining a method of bonding the first and second nanostructures.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. In the accompanying drawings, the sizes and the quantities of objects are shown enlarged or reduced from the actual size for the sake of clarity of the present invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprise", "comprising", and the like are intended to specify that there is a feature, step, function, element, or combination of features disclosed in the specification, Quot; or " an " or < / RTI > combinations thereof.

On the other hand, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

1 is a flowchart illustrating a method of manufacturing a solar absorber according to an embodiment of the present invention.

Referring to FIG. 1, according to a method of manufacturing a solar absorber according to an exemplary embodiment of the present invention,

First, a first nanostructure is formed (S110). In order to form the first nanostructure, a metal layer is prepared, and then a first conductive nano pattern is formed on the metal layer.

The metal layer may be formed on the first substrate through an evaporation process or a sputtering process. The metal layer may be made of a metal having a relatively large work function in order to prevent layer deterioration during driving. For example, the metal layer may be formed of at least one selected from the group consisting of Ru, Rh, Pd, Ag, Os, Ir, Au, Pt, Au, Al, Cr, Cu, Ni, Mo, Pd, Ta, Co, Fe, . ≪ / RTI > In addition, the metal plate 110 may be formed using a metal alloy such as SUS, nichrome, or duralumin.

In addition, the first conductive nano pattern is formed on the metal layer. The first conductive nanopattern may have a nanoscale width, length, or spacing. The first conductive nano-pattern may be formed by a method of forming a first conductive nano-pattern by using a conductive nano-pattern, such as e-beam lithography, photolithography, X-ray lithography, EUV lithography, ion-beam lithography, laser interference lithography, holography lithography, micro contact printing, soft lithography, or the like.

Meanwhile, a dielectric layer may be additionally formed between the metal layer and the first conductive nano pattern. The dielectric layer may be formed by a chemical vapor deposition process, a physical vapor deposition process, and a chemical mechanical polishing process for planarizing the preliminary dielectric layer after forming the preliminary dielectric layer. Alternatively, the dielectric layer may be formed by spin coating with a plurality of dielectric thin films.

The dielectric film may include binary oxides such as silicon oxide, aluminum oxide, molybdenum oxide, zinc oxide, iron oxide, manganese oxide, vanadium oxide, tungsten oxide, gallium oxide, indium oxide, tin oxide, lead oxide, zirconium oxide and hafnium oxide . Also, the dielectric layer may include nitrides such as zirconium nitride, titanium nitride, aluminum nitride, and silicon nitride. Further, the dielectric thin film 140 may be composed of halides such as magnesium fluoride, lithium fluoride, calcium chloride, and potassium chloride. The dielectric thin film 140 may be made of a ternary compound such as SiON, PbTiO ₃ , BaTiO ₃ , MgAl ₂ O _3, and the like.

Subsequently, a second nanostructure is formed (S130). In order to form the second nanostructure, a sacrificial layer is prepared and a second conductive nanopattern is formed on the sacrificial layer.

The sacrificial layer may be formed on the second substrate through a spin coating process. The sacrificial layer may be formed using a photosensitive resin. At this time, the sacrificial film can be easily removed in a subsequent process.

The second conductive nanopattern may have a nanoscale width, length or spacing. The second conductive nanopattern may be formed by a combination of e-beam lithography, photolithography, X-ray lithography, EUV lithography, ion-beam lithography, laser interference lithography, holography lithography, nanomimprint lithography, micro contact printing, soft lithography, or the like.

Next, the second nanostructure is bonded on the first nanostructure so that the first and second conductive nanopatterns face each other (S150). As a result, the solar absorbing body in which the first conductive nano patterns and the second conductive nano patterns are stacked in the vertical direction is manufactured.

In order to bond the second nanostructure on the first nanostructure, a pre-bonding layer is formed on the first nanostructure using a thermosetting resin. Thereafter, the second nanostructure is placed on the first nanostructure, and then the first and second nanostructures are thermally pressed through a thermosetting process to bond the second nanostructure on the first nanostructure can do.

Thus, the first conductive nano patterns may be arranged in different planes and may have a stack structure stacked in a plurality of layers.

In one embodiment of the present invention, each of the first and second conductive nanopatterns may have a bar shape. The first and second conductive nano patterns may extend in a first direction parallel to each other. Alternatively, the first and second conductive nanopatterns may extend to cross each other in different planes.

Each of the first and second conductive nanopatterns may have a C-shape. Whereby each of the first and second conductive nanopatterns may have a split ring resonator (SRR) shape. In addition, the first and second conductive nano patterns may have S-shaped shapes in different planes. At this time, since the conductive nano patterns are formed to cross each other, they may have swastika as a whole according to the load.

FIGS. 2 to 7 are cross-sectional views illustrating a method of forming the first nanostructure.

Referring to FIG. 2, a metal layer 111 and a dielectric layer 112 are sequentially stacked on a first substrate 101. The metal layer 111 and the dielectric layer 112 may be formed through, for example, an evaporation process. At this time, the dielectric layer may be formed to a thickness of several tens nm, for example, 20 nm.

Referring to FIG. 3, a first undercut forming film 121 is formed on the dielectric layer 112. The first undercut forming layer 121 may be formed using a material that maintains adhesion with the dielectric layer 112 and is readily soluble in the solvent used in the subsequent lift-off process. For example, the first undercut forming film 121 may be a LOL 1000 ^TM (manufactured by Shipley).

The first undercut forming film 121 may be formed through a spin coating process. The first undercut forming film 121 may have a thickness of several hundred nm, for example, 200 nm.

Referring to FIG. 4, a first mask pattern 126 is formed on the first undercut forming film 121. The first mask pattern 126 may be formed through a nanoimprint lithography process using a stamp. In this case, the shape and shape of the first mask pattern 126 may be adjusted according to the shape and shape of the stamp. The spacing between the first mask patterns 126 may correspond to the width of the first conductive nano patterns 115 formed subsequently.

Referring to FIG. 5, the first undercut forming film 121 is patterned using the first mask pattern 126 to form a first undercut forming film pattern 123 on the dielectric film 112. For example, the first undercut forming film pattern 123 can be formed through a reactive ion etching process using the first mask pattern 126 as an etching mask. In this case, the dielectric layer 112 may be partially exposed between the first undercut forming film patterns 123.

Referring to FIG. 6, a first metal thin film 115 is formed isotropically on the entire first substrate 101 including the first mask pattern 126 and the first undercut forming film pattern 123. The first metal thin film 115 may be formed, for example, by an ion beam deposition process. Accordingly, the first metal thin film 115 may be formed on the first mask pattern 126 and on the exposed dielectric film 112, respectively.

The first metal thin film 115 may include at least one of Ru, Rh, Pd, Ag, Os, Ir, Au, Pt, Au, Al, Cr, Cu, Ni, Mo, Pd, Ta, Co, And W. < / RTI > In addition, the first metal thin film 115 may be formed using a metal alloy such as SUS, nichrome, or duralumin.

Referring to FIG. 7, the first undercut forming film pattern 123 is removed from the substrate 101 through a lift-off process. Thus, the first conductive nano pattern 113 is formed on the dielectric layer 112.

According to the lift-off process, the first mask pattern 126 formed on the first undercut formation film pattern 123 is removed by removing the first undercut formation film pattern 123 through a wet etching process using an etchant, A part of the first metal thin film 115 can be removed together.

Accordingly, the first conductive nano pattern 113 can be easily formed on the dielectric layer 112 through the nanoimprinting lithography process and the lift-off process.

FIGS. 8 to 13 are cross-sectional views illustrating a method of forming the second nanostructure.

Referring to FIG. 8, a sacrificial layer 105 is formed on a second substrate 102. The sacrificial layer 105 may be formed, for example, by a spin coating process. The sacrificial layer 105 may be formed using a photosensitive resin. Thus, the sacrificial film 105 can be easily removed in a subsequent developing process. The sacrificial layer 105 may be formed to a thickness of several hundreds nm, for example, 500 nm.

Referring to FIG. 9, a second undercut forming film 122 is formed on the sacrificial layer 105. The second undercut forming film 122 may be formed using a material that maintains adhesion with the sacrificial film 105 and is readily soluble in the solvent in a subsequent lift-off process. For example, the second undercut forming film 105 may be a LOL 1000 ^TM (manufactured by Shipley).

The second undercut forming film 122 may be formed through a spin coating process. The second undercut forming film 122 may have a thickness of several hundreds nm, for example, a thickness of 200 nm.

Referring to FIG. 10, a second mask pattern 127 is formed on the second undercut forming film 122. The second mask pattern 127 may be formed through a nanoimprint lithography process using a stamp. In this case, the shape and shape of the second mask pattern 127 may be adjusted depending on the shape and shape of the stamp. Also, the distance between the second mask patterns 127 may correspond to the width of the second conductive nano pattern 114 (see FIG. 13) formed subsequently.

Referring to FIG. 11, the second undercut forming film 122 is patterned using the second mask pattern 127 to form a second undercut forming film pattern 124 on the sacrificial film 105. For example, the second undercut formation film pattern 124 can be formed through a reactive ion etching process using the second mask pattern 127 as an etching mask. In this case, the sacrificial layer 105 may be partially exposed between the second undercut forming film patterns 124.

Referring to FIG. 12, a second metal thin film 116 is formed isotropically on the entire surface of the second substrate 105 including the second mask pattern 127 and the second undercut forming film pattern 124. The second metal thin film 116 may be formed through, for example, an ion beam deposition process. Accordingly, the second metal thin film 116 may be formed on the second mask pattern 127 and on the exposed dielectric film 105, respectively. The second metal thin film 116 may be made of the same metal as the first metal thin film.

Referring to FIG. 13, the second undercut forming film pattern 124 is removed from the second substrate 105 through a lift-off process. As a result, the second conductive nano pattern 114 is formed on the sacrificial layer 105.

In the lift-off process, the second mask pattern 127 formed on the upper portion of the second undercut formation film pattern 124 is removed by removing the second undercut formation film pattern 124 through a wet etching process using an etching solution. A part of the second metal thin film 116 can be removed together.

Accordingly, the second conductive nano pattern 114 can be easily formed on the sacrificial layer 105 through the nanoimprinting lithography process and the lift-off process.

Figs. 14 to 16 are cross-sectional views for explaining a method of bonding the first and second nanostructures.

14 and 15, the second nanostructure is bonded on the first nanostructure so that the first and second conductive nano patterns 113 and 114 face each other. Thus, a solar absorbing body in which the first conductive nano patterns 113 and the second conductive nano patterns 114 are stacked in the vertical direction is manufactured.

In order to bond the second nanostructure on the first nanostructure, a pre-bonding layer 141 is formed on the first nanostructure using a thermosetting resin.

Thereafter, the second nanostructure is placed on the first nanostructure, and then a bonding layer 140 is formed through a thermosetting process. Further, by thermally pressing the first and second nanostructures together, The second nanostructure may be bonded to the second nanostructure. The first conductive nano patterns 113 and the second conductive nano patterns 114 may be arranged in different planes and may have a stack structure stacked in a plurality of layers.

In one embodiment of the present invention, the sacrificial layer 105 may use HSQ material. Thus, the sacrificial film 105 can be easily removed by development, and the second substrate 102 can be removed together. Thus, a solar absorbing body in which the first and second conductive nano patterns 113 and 114 are stacked in the vertical direction can be manufactured.

Meanwhile, the third nanostructure corresponding to the second nanostructure may be formed and vertically stacked through the bonding process, thereby manufacturing a solar absorber including a plurality of vertically stacked conductive nanopatterns.

According to the above-described method of manufacturing a solar absorber, a first nanostructure including a first conductive nanopattern and a second nanostructure including a second conductive nanopattern are formed, and the first and second nanostructures are bonded to each other Thereby making it possible to easily manufacture a solar absorber in which structures in which the first and second conductive nano patterns are stacked vertically are stacked. In addition, various shapes of conductive nanopatterns can be realized using a lift-off process and a nanoimprint lithography process.

The manufacturing method of the solar absorber can be applied to military technology, solar cell technology, thermoelectric device technology, etc. which can absorb heat and avoid tracing.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. It can be understood that it is possible.

Claims (7)

Forming a metal layer and a first nanostructure having a first conductive nanopattern on the metal layer;
Forming a sacrificial layer and a second nanostructure having a second conductive nanopattern on the sacrificial layer;
Forming a pre-bonding layer on the first nanostructure using a thermosetting resin; And
Inverting one of the first and second nanostructures with respect to the other and bonding the second nanostructure on the first nanostructure so that the first and second conductive nanopatterns face each other Including,
Wherein bonding the second nanostructure to the first nanostructure comprises thermally curing the pre-bonding layer through a thermal curing process to convert the pre-bonding layer into a bonding layer. delete 2. The method of claim 1, wherein forming the first nanostructure comprises:
Sequentially forming the metal layer and the dielectric layer on the first substrate;
Forming a first undercut forming film on the dielectric film;
Forming a first mask pattern on the first undercut forming film through a nanoimprinting lithography process;
Forming a first undercut formation film pattern by patterning the first undercut formation film using the first mask pattern; And
Forming a first metal thin film isotropically on a first substrate including the first undercut forming film pattern; And
And removing the first undercut forming film pattern from the first substrate through a lift-off process to form a first conductive nano pattern on the dielectric film. 2. The method of claim 1, wherein forming the second nanostructure comprises:
Forming a sacrificial film on the second substrate;
Forming a second undercut forming film on the sacrificial film;
Forming a second mask pattern on the second undercut forming film through a nanoimprinting lithography process;
Forming a second undercut formation film pattern by patterning the second undercut formation film using the second mask pattern;
Forming a second metal thin film isotropically on a second substrate including the second undercut forming film pattern; And
And removing the second undercut forming film pattern from the second substrate through a lift-off process to form a second conductive nano pattern on the sacrificial film. 3. The method of claim 1, wherein each of the first and second conductive nanopatterns has a bar shape extending in parallel to each other, a cross bar shape extending to cross each other, a C- Shaped shape so as to form an S shape. The method of claim 1, wherein the sacrificial layer is formed of a hydrogen silsesquioxane (HSQ) material. The method of claim 1, further comprising removing the sacrificial film.

Images