TW201328965A - Method of fabricating anti-reflective layer and anti-reflective layer fabricated by the same - Google Patents

Abstract

A method of fabricating an anti-reflective layer and an anti-reflective layer fabricated by the same. The method of fabricating an anti-reflective layer of the present invention comprises steps: (A) providing a substrate; (B) forming plural nanowires standing over the substrate; (C) forming a covering layer on the nanowires; (D) removing part of the covering layer to expose the top of the nanowires; and (E) removing the nanowires to thus form plural nanotubes standing over the substrate. The method of the present invention offers a simple, efficient, and low cost process, the highly transparent nanotube arrays in the present invention can serve as not only light wave-guiding medium but also a graded refractive index structure.

Description

Method for preparing antireflection layer and antireflection layer prepared by the method

The present invention relates to a method for preparing an antireflection layer and an antireflection layer prepared by the method, and more particularly to a method for preparing an antireflection layer having a plurality of nanotubes and the antireflection layer.

Anti-reflective layers are used in a wide variety of applications, such as anti-reflection of optical lens surfaces or display surface anti-reflection.

In the prior art, a nanomaterial is deposited or grown on the surface of an optical device, component or crystal grain as an anti-reflective structural layer, which is a process technology with a wide range of anti-reflection effects. At present, the conventional reflective layer fabrication techniques can be roughly summarized into the following two methods:

1. Multi-layer film structure: This system utilizes a film as an anti-reflection layer. The theoretical basis is that the product of the refractive index and the thickness of the film is an odd multiple of a quarter of the wavelength of the incident wave, so that the reflected wave forms destructive interference. And the effect of making the incident wave reflectance close to zero. Although such a design can theoretically reduce the reflection of a specific wavelength, it is often not easy to use a single layer of material to obtain a sufficiently low refractive index in a specific wavelength band. Therefore, a multilayer film structure is generally used to achieve a specific A more complete anti-reflection effect on the band.

In addition, the fabrication of the multilayer film structure usually requires vacuum evaporation of a plurality of layers of materials having different refractive indices on the substrate, but the main disadvantage is that it is difficult to achieve an anti-reflection effect in a wide range of wavelength bands, and the cost of vacuum evaporation is adopted. Higher.

Second, the non-uniform layer structure:

This is to deposit or stack multiple layers of material on the surface of the substrate, and use this layer of heterogeneous material to obtain a surface structure with a graded index of refraction to achieve an anti-reflection effect in a specific wavelength band. The anti-reflection structure fabricated by this principle includes: a Subwavelength Structure, a Nano-Porous Film, and a Nanocorrugation Surface.

In general, such heterogeneous structures are less sensitive to light incident angles and are more suitable for anti-reflective film fabrication with a wide angle of incidence. Moreover, the non-uniform layer structure is less restricted in material selection, and its applicable working bandwidth is larger than that of the conventional multilayer interferometric coating, and is an anti-reflection film which has been widely studied recently and has been widely used.

The fabrication technique of the non-uniform layer structure mainly uses optical interference lithography or electron beam lithography to form a designed pattern on the photoresist, and then forms a nanostructure on the substrate by an etching process. Such a process using the traditional lithography technology, although it is convenient to carry out the production of the nanostructure and anti-reflection application, the process is more complicated, and the lithography process has higher cost and slower output. Large-area solar cells or display panels are less competitive.

The nanoparticles are coated on the substrate, and the nano-particles are used as an etching mask to etch the surface of the substrate into a nano-column structure. This is also a common anti-reflection material in recent years (refer to Gong- Ru Lin et al., "Low refractive index Si nanopillars on Si substrate", Appl. Phys. Lett. 90, 181923 (2007) and Sen Wang et al., "Simple lithographic approach for subwavelength structure antireflection", Appl. Phys. Lett. 91,061105 (2007)). The coating of nano particles, especially on large-area substrates, is difficult to control the uniformity, which is a big challenge in the process technology.

In addition, nanoimprint technology is also the production method of another very common nanostructure anti-reflective material in the near future. However, the molds required for imprinting still need to rely on the precision lithography process to maximize the performance. Efficacy, similar to nanoparticle coating technology, also faces the problem of high cost and difficult process.

The fabrication technology of the nano column structure anti-reflection layer on the surface of the substrate has become a popular anti-reflective material because of its remarkable anti-reflection effect, low cost, simple process and wide application in large-area production. Technology, in which the nano column of zinc oxide is the most popular (refer to Yun-JuLee et al., "ZnO Nanostructures as Efficient Antireflection Layers in Solar Cells", Nano Lett. Vol. 8 No. 5 1501-1505 (2008) And M. Krunks et al., "Nanostructured solar cell based on spray pyrolysis deposited ZnO nanorod array", Solar Energy Materials & Solar Cells 92 (2008) 1016-1019), however, since the zinc oxide nanowire energy gap width is only 3.3 ~3.7eV, which is a light absorbing material in some visible light and ultraviolet light bands, the transmittance of zinc oxide nano column array is not high, which reduces the probability of light entering the substrate from the surface, so it is not suitable for solar cell applications, but still There is room for improvement.

Accordingly, the present invention discloses a nanotube array fabrication technique with high energy gap/high transmittance, variable refractive index and very low reflectance characteristics, which is characterized by optical devices, components or die surfaces, The nano tube array anti-reflection structure with roughened and graded refractive index, on the one hand, eliminates reflection by scattering of incident light between the nanotubes, and on the other hand, the incident light is introduced into the element by the light guiding action of the nanotube itself. Internally, the characteristics of high transmittance and low reflectivity are obtained. The anti-reflective material nano tube array structure made of a material having high light transmittance characteristics (such as SiO ₂ , TiO ₂ , HfO ₂ , ZrO ₂ , HfLaO, Si ₃ N ₄ and AlN, etc.) is easy to process for a large area. In addition to avoiding the shortcomings of traditional light absorption of zinc oxide nanowires, the light guide effect of the nanotubes can be utilized to effectively reduce the reflectivity, which is highly progressive and applicable.

The method for preparing a nano tube anti-reflection layer of the present invention comprises the steps of: (A) providing a substrate; (B) forming a plurality of nanowires standing on the substrate; (C) forming a coating layer on the substrate. a surface of the nanowire; (D) removing a portion of the coating to reveal the top ends of the nanowires; and (E) removing the nanowires to form a plurality of nanotubes standing upright on the substrate on.

The preparation method of the nano tube anti-reflection layer of the invention has the following advantages:

1. The overall production process is a low temperature process.

2. No need to use expensive epitaxial or optical coating equipment and processes.

3. No need for catalyst, easy process, and low cost.

4. The anti-reflective nanotube array has the advantages of structure (length, inner/outer diameter and density of the nanotubes) and the material can be easily modulated.

The invention utilizes a high light transmission characteristic material to fabricate a nano tube array anti-reflection structure, and the manufacturing technology comprises the following steps: hydrothermal growth of zinc oxide nanowire, deposition of high light transmission characteristic material (covering insulating material, semiconductor material, or The conductive material, etc.), and the process of removing the zinc oxide nanowire by an etching process, all of which are low-temperature processes, do not require expensive epitaxial or optical coating equipment and processes, and do not require catalyst, and have a process The advantages of simplicity and low cost.

Furthermore, the nano tube array anti-reflection structure of different materials (including insulating materials, semiconductors and conductor materials, etc.) can be obtained through material selection and process parameter modulation. The incident light is introduced into the element by the scattering of the incident light between the nanotubes and the light guide of the nanotube itself. It is experimentally confirmed that a very low reflectance (≦1.5%) can be obtained in the 400-800 nm spectrum range. This has great potential in the application of optical components and equipment and solar cell anti-reflection, and has great business opportunities in the optoelectronic industry.

In the preparation method of the present invention, the step (A) preferably further comprises a step (A1) of forming a seed layer on the surface of the substrate.

In the preparation method of the present invention, the substrate of the step (A) is preferably selected from the group consisting of a glass substrate, a quartz substrate, a semiconductor substrate, a transparent conductive coated glass substrate, a ceramic substrate, a metal substrate, a polymer material substrate, a sapphire substrate, and a surface. A substrate and a group of electronic components are provided. Therefore, the method for preparing the nano tube anti-reflection layer of the present invention can be applied to optical lenses, various displays, solar cells, or other optical devices to impart an anti-reflection function.

In the preparation method of the present invention, the material of the seed layer may preferably be: zinc aluminum oxide (AZO), indium zinc oxide (IZO), gallium zinc oxide (GZO), or zinc oxide (ZnO), Or a combination thereof, or other conductive metal or semiconductor film with high acid and alkali resistance.

In the preparation method of the present invention, the part of the step (D) is preferably a method of removing the coating layer by an inductively coupled plasma (ICP) method.

In the preparation method of the present invention, the exposed length of the nanowires in the step (D) may preferably be 1 μm or less. For example, 0.5 μm, or 0 μm, as long as the nanowire is not completely covered by the blanket.

In the preparation method of the present invention, the removal of the nanowire of the step (D) is preferably performed by immersing in a selective solution, and wherein the selective solution is preferably for the nanowire and the coating layer. Has etch selectivity.

In the preparation method of the present invention, the thickness of the nanotubes is preferably from 1 nm to 1000 nm, the length is preferably from 0.5 μm to 10 μm, and the diameter is preferably from 30 nm to 1500 nm. The length of the tube affects the anti-reflection and penetration properties of the light. If the length of the tube is too long, the penetration rate will be too low; however, if the length of the tube is too short, sufficient anti-reflection effect will not be achieved. Therefore, the length of the nanotube should be properly controlled.

In the preparation method of the present invention, the nanowires may preferably be zinc oxide-based nanowires, and preferably the nanowires are formed by a hydrothermal method. Further, the zinc oxide base wire preferably has a hexagonal column shape.

In the preparation method of the present invention, the materials of the nanotubes (ie, the coating layer) may preferably be a transparent insulating material, a transparent semiconductor material, a transparent conductive material or a combination thereof. For example, the materials of the nanotubes may be cerium oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), nickel oxide (NiO), indium tin oxide (InSnO), indium zinc oxide. (InZnO), aluminum zinc oxide (AlZnO), gallium zinc oxide (GaZnO), copper boron oxide (CuBO ₂ ), copper aluminum oxide (CuAlO ₂ ), copper gallium oxide (CuGaO ₂ ), copper indium Oxide (CuInO ₂ ), bismuth (Si), gallium arsenide (GaAs), tantalum nitride (Si ₃ N ₄ ), tantalum nitride (TaN), tantalum oxide (HfLaO), titanium telluride (TiSi ₂ ) Titanium nitride (TiN), hafnium oxide (HfO ₂ ) or a combination thereof.

Furthermore, the present invention further provides a nanotube anti-reflection layer, which is preferably produced according to the above method, and includes: a substrate; a plurality of nanotubes erected on the substrate; wherein the nano The length of the rice tube is 0.5 μm to 10 μm, the outer diameter is 30 nm to 1500 nm, and the wall thickness is 1 nm to 1000 nm. The material of the nanotube is a transparent insulating material, a transparent semiconductor material, a transparent conductive material or a combination thereof. .

The nano tube anti-reflection layer of the invention has the characteristics of sub-wavelength structure, surface roughening, gradual refractive index, and light guiding effect of the nanotube array, so as to effectively reduce the reflection of incident light and achieve resistance. Reflection function. In detail, the present invention has a sub-wavelength nanotube structure on the surface to reduce scattering generated when light passes, and utilizes the light guiding effect and surface roughening effect of the nanotube to effectively guide light into the inside of the element. Moreover, the reflection of the surface light can be further reduced by the characteristic of the graded refractive index of the structure.

The invention eliminates reflection by scattering of incident light between the nanotubes, and uses the nanotube structure to have a graded refractive index and a light guide to introduce incident light into the interior of the component. Moreover, it has been confirmed through experiments that the nanotube antireflection layer of the present invention can obtain high transmittance (≧90%) and extremely low reflectance (≦1.5%) in the spectral range of 400 to 800 nm.

The novel nanotube anti-reflection layer technology of the invention belongs to the technical innovation, and is very helpful for reducing the reflection of incident light on the surface of the component and the introduction of incident light, so it is very advanced, and in terms of solar cells and optical equipment. It also has a very high application value.

The nano tube anti-reflection layer of the present invention is preferably used for providing an anti-reflection function, and the reflectance of the nanotube anti-reflection layer for light having a wavelength range of 400 nm to 800 nm is preferably 1.5% or less.

In the present invention, the length of the nanotube tube affects the anti-reflection and penetration properties of the light. If the length of the nanotube tube is too long, the penetration rate is too low; however, if the length of the nanotube tube is too short, sufficient Anti-reflective effect. Therefore, the length of the nanotube should be properly controlled.

In the present invention, the nanotubes can be arranged in a regular or irregular array, and the nanotube density can be adjusted according to the process conditions.

In the nano tube anti-reflection layer of the present invention, the substrate is preferably selected from the group consisting of a glass substrate, a quartz substrate, a semiconductor substrate, a transparent conductive coated glass substrate, a ceramic substrate, a metal substrate, a polymer material substrate, a sapphire substrate, and a surface. A substrate and a group of electronic components are provided.

Preferably, the nano tube anti-reflective layer of the present invention further comprises a seed layer disposed between the substrate and the plurality of nanotubes.

In the anti-reflection layer of the nanotube of the present invention, the thickness of the seed layer may preferably be 10 to 500 nm.

In the nano tube anti-reflection layer of the present invention, the plurality of nanotube tubes are irregularly distributed, and the plurality of nanotube tubes are preferably: each independently arranged in a single arrangement; two or more adjacent arrays; or simultaneously independently A single arrangement and two or more adjacent arrangements.

In the nanotube antireflection layer of the present invention, the length of the nanotube is preferably from 1 μm to 10 μm. Moreover, the materials of the nanotubes are preferably cerium oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), nickel oxide (NiO), indium tin oxide (InSnO), indium. Zinc oxide (InZnO), aluminum zinc oxide (AlZnO), gallium zinc oxide (GaZnO), copper boron oxide (CuBO ₂ ), copper aluminum oxide (CuAlO ₂ ), copper gallium oxide (CuGaO ₂ ), Copper indium oxide (CuInO ₂ ), bismuth (Si), gallium arsenide (GaAs), tantalum nitride (Si ₃ N ₄ ), tantalum nitride (TaN), tantalum oxide (HfLaO), titanium telluride (TiSi) ₂ ), titanium nitride (TiN), yttrium oxide (HfO ₂ ) or a combination thereof.

The embodiments of the present invention are described by way of specific examples, and those skilled in the art can readily appreciate the other advantages and advantages of the present invention. It should be noted that the following drawings are simplified schematic diagrams. The number, shape and size of components in the drawings can be changed arbitrarily according to actual implementation conditions, and the component layout state can be more complicated. The present invention may be embodied or applied in various other specific embodiments, and various modifications and changes can be made without departing from the spirit and scope of the invention.

[pre-job]

In the pre-operation, the following materials must be prepared:

(1) Substrate: an n- or p-type semiconductor substrate, an insulator (glass or ceramic or dielectric material) substrate, a metal substrate, or a sapphire substrate (Sapphire Substrate).

(2) Seed layer target: zinc aluminum oxide (AZO), indium zinc oxide (IZO), gallium zinc oxide (GZO) or zinc oxide (ZnO) or a combination thereof.

(3) Highly transparent oxide or semiconductor materials: cerium oxide (SiO ₂ ), titanium dioxide (TiO ₂ ), hafnium oxide (HfO ₂ ), zirconium dioxide (ZrO ₂ ), hafnium oxide (HfLaO) , tantalum nitride (Si ₃ N ₄ ) and aluminum nitride (AlN), etc. or a combination thereof.

[Example 1]

First, a substrate 11 (shown in FIG. 1A) was provided, and the substrate 11 was washed with deionized water for 5 minutes, and then immersed in a mixed solution of H ₂ SO ₄ :H ₂ O ₂ =3:1 for 10 minutes. Subsequently, it was washed with deionized water for 5 minutes, and soaked for 20 seconds with a mixed solution of HF:H ₂ O = 1:100, and again washed with deionized water for 5 seconds.

A mixed solution of NH ₄ OH:H ₂ O ₂ :H ₂ O=1/4:1:5 was prepared and immersed for 10 minutes. Next, after washing with deionized water for 5 minutes, a mixed solution of HCL:H ₂ O ₂ :H ₂ O=1:1:6 was prepared and immersed for 10 minutes. Wash again with deionized water for 5 minutes. Soak in a mixed solution of HF:H ₂ O=1:100 for 15-20 seconds, finally wash with deionized water for 5 seconds, and blow dry with nitrogen.

Next, deposition of a seed layer (this is an optional step) is performed to completely or partially coat the substrate with a seed layer (not shown). It should be noted that except for the gallium nitride-based or zinc oxide-based substrate, any substrate with poor lattice matching with zinc oxide (0001) surface must deposit a seed layer to facilitate the growth of zinc oxide nanowires. .

The deposition system used to form the seed layer here is a DC/RF sputtering system or an evaporation system. The deposition conditions are: power 200 W, deposition rate 0.4 /sec, vacuum condition 7.6x10 ^-3 torr, argon (Ar) flow rate 24 sccm. The seed layer material is: zinc aluminum oxide (AZO), indium zinc oxide (IZO), gallium zinc oxide (GZO), or zinc oxide (ZnO), or a combination thereof. The optimum thickness of the desired seed layer is: 100~500 nm.

Next, as shown in FIG. 1B, the zinc oxide nanowires 12 are grown by hydrothermal method (HTG) (the diameters of the different zinc oxide nanowires 12 are slightly different). The mixed solution components used therein include: 800 ml of deionized water, 6 g of zinc nitrate (Zinc Nitrate), and 3 g of hexamethylenetetramine (HMT). The growth conditions were as follows: The test piece was allowed to stand in a mixed solution maintained at 85 ° C for 40-120 minutes. The diameter and length of the prepared zinc oxide nanowires are 40 to 200 nm and 1 to 2 μm, respectively. As shown in the electron microscopy results of Fig. 2A, the zinc oxide nanowires grown by hydrothermal method are clearly visible in terms of the vertical alignment of the growth of the nanowires, in terms of aspect ratio, uniformity or even density. It is easier to get control.

Next, as shown in FIG. 1C, the surface of the zinc oxide nanowires 12 is plated with a highly transparent oxide or semiconductor material such as SiO ₂ , TiO ₂ , HfO ₂ , ZrO ₂ , HfLaO, Si ₃ N _{4 .} With AlN, etc. or a combination thereof. Here, the ruthenium dioxide film 13 is plated. Deposition systems that can be used, such as chemical or physical vapor deposition (CVD), DC/RF sputter systems, thermal evaporators, electron beam deposition (e-beam). Here, the film thickness of the ceria film 13 is about 1 μm on average. In the present invention, the thickness of the light-transmissive oxide or semiconductor material can be controlled by chemical vapor deposition, that is, the thickness of the tube wall of the nanotube can be modulated, and the equivalent refractive index and photoconductivity of the nanotube array can be further modulated. As shown in the electron microscope results of FIG. 2B, the ruthenium dioxide film 13 is coated on the upper end and the side wall of the zinc oxide nanowire 12, and the structure of the zinc oxide nanowire 12/cerium oxide film 13 has a uniform wire diameter and length. Density distribution.

Thereafter, as shown in FIG. 1D, the portion of the ceria film 13 is etched to expose the zinc oxide nanowire 12 having a length of about 0.5 μm. The etching system can be, for example, dry etching (RIE, ICP, etc.) or chemical solution wet etching (BOE, etc.). Conditions for dry etching: RF power of 80 W, ICP power of 2500 W, and etching rate of 45 /sec, the vacuum condition is 7.5 × 10 ^-9 torr, and the C ₄ F ₈ flow rate is 45 sccm. The optimum thickness of oxide etching: 100~500 nm. As shown in the electron microscopy results of Fig. 2C, after partial etching of the cerium oxide by ICP, a zinc oxide nanowire having a length of about 0.5 μm was exposed on the test piece. In addition, the length of the final ruthenium dioxide nanotube can be determined by ICP dry etching.

Next, as shown in FIG. 1E, the structure of the zinc oxide nanowire 12/cerium oxide film 13 is immersed in a selective mixed solution for etching to remove the zinc oxide nanowire 12, thereby obtaining a plurality of oxidations.矽 Nano tube 14. Here, the composition of the mixed solution for etching was: 500 ml of deionized water, 50 ml of a phosphoric acid solution (H ₃ PO ₄ ) and 10 ml of hydrochloric acid (HCl). Etching conditions: statically placed in a mixed solution at room temperature for 5-10 minutes. As shown in the electron microscope results of Fig. 2D, it is a top view of the ruthenium dioxide nanotubes prepared in the present example, and the structure of the ruthenium dioxide nanotubes after etching can be seen. The length of the ruthenium dioxide nanotube 14 prepared in this example and the thickness of the outer tube wall were 1.5 μm and 200 nm, respectively.

[Test Example 1] Energy Dispersive Spectrum (EDS) test

3A-3C are graphs showing the results of energy scatter spectrum analysis of the structures of the respective steps (corresponding to Figs. 1B, 1D, and 1E, respectively) in the first embodiment of the present invention. 3A-3C are graphs of energy dispersive spectroscopy results of zinc oxide nanowires, zinc oxide/cerium oxide nanostructures, and post-etched germanium dioxide nanotubes, respectively. From the main waveform signals shown in the respective figures, it was confirmed that the obtained test pieces were respectively confirmed to have zinc oxide, zinc oxide, cerium oxide, and cerium oxide. A small amount of platinum (Pt) signal appears in the scattering spectrum and should be caused by the previous processing of the electron microscope test.

[Test Example 2] Measurement of permeability characteristics

4 is a graph showing measurement results of penetration characteristics of each step (corresponding to FIGS. 1B, 1D, and 1E, respectively) in Embodiment 1 of the present invention. Among them, the curves (a), (b), and (c) are the results of analysis of the penetration characteristics of the zinc oxide nanowire, the zinc oxide/cerium oxide nanostructure, and the post-etched ruthenium dioxide nanotube. As can be seen from the results of FIG. 4, the cerium oxide nanotube 14 has an average transmittance of 92% or more, which is higher than that of the grown zinc oxide nanowire (~80%). More than 12% increase. Therefore, it has been proved by the measurement of the transmittance characteristics that the ruthenium dioxide nanotubes produced by the technique of the present invention are extremely useful for the application of optoelectronic components.

[Test Example 3] Measurement of reflectance characteristics

The reflectance characteristics were measured by taking the gallium nitride substrate, the structure shown in FIG. 1B, and the structure shown in FIG. 1E, and the results are shown in FIGS. 5A and 5B. Fig. 5A shows the results of the reflectance characteristics of the structures shown in Fig. 1B and Fig. 1E. As can be seen from Fig. 5A, in the visible light band (400 nm to 800 nm), the cerium oxide nanotubes have an average of 1.5% or less. Reflectivity. The reflectivity of the gallium nitride substrate (shown in FIG. 5B) which is not covered with the ruthenium dioxide nanotube is higher than 20%. Therefore, according to the measurement results of the reflectance characteristics, it can be confirmed that the structure of the ruthenium dioxide nanotube array fabricated by the present invention is extremely useful and potential.

In summary, the present invention discloses a nanotube array fabrication technique with high energy gap/high transmittance, variable refractive index, and very low reflectance characteristics, which are characterized by optical devices, components, or grain surfaces. A nano tube array anti-reflection structure with roughened and graded refractive index is fabricated. On the one hand, the reflection of the incident light between the nanotubes is used to eliminate the reflection, and on the other hand, the incident light is made by the light guide of the nanotube itself. It is introduced into the inside of the component to obtain high transmittance and low reflectivity. The anti-reflective material nano tube array structure made of a material having high light transmittance characteristics (such as SiO ₂ , TiO ₂ , HfO ₂ , ZrO ₂ , HfLaO, Si ₃ N ₄ and AlN, etc.) is easy to process for a large area. In addition to avoiding the shortcomings of traditional light absorption of zinc oxide nanowires, the light guide effect of the nanotubes can be utilized to effectively reduce the reflectivity, which is highly progressive and applicable.

The preparation method of the nano tube anti-reflection layer of the invention has the following advantages:

1. The overall production process is a low temperature process.

2. No need to use expensive epitaxial or optical coating equipment and processes.

3. No need for catalyst, easy process, and low cost.

4. The anti-reflective nanotube array has the advantages of structure (length, inner/outer diameter and density of the nanotubes) and the material can be easily modulated.

The invention utilizes a high light transmission characteristic material to fabricate a nano tube array anti-reflection structure, and the manufacturing technology comprises the following steps: hydrothermal growth of zinc oxide nanowire, deposition of high light transmission characteristic material (covering insulating material, semiconductor material, or The film of conductor material, etc., and the process of removing the zinc oxide nanowire by etching process, all of which are low-temperature processes, do not need expensive epitaxial or long crystal equipment and processes, and do not need catalyst, and have process The advantages of simplicity and low cost.

Furthermore, the nano tube array anti-reflection structure of different materials (including insulating materials, semiconductors and conductor materials, etc.) can be obtained through material selection and process parameter modulation. The incident light is introduced into the element by the scattering of the incident light between the nanotubes and the light guide of the nanotube itself. It is experimentally confirmed that a very low reflectance (≦1.5%) can be obtained in the 400-800 nm spectrum range. This has great potential in the application of optical components and equipment and solar cell anti-reflection, and has great business opportunities in the optoelectronic industry.

The above-mentioned embodiments are merely examples for convenience of description, and the scope of the claims is intended to be limited to the above embodiments.

11. . . Substrate

12. . . Zinc oxide nanowire

13. . . Cerium oxide film

14. . . Ceria nanotube

1A-1E are flow charts showing the preparation of the nanotube anti-reflection layer of Example 1 of the present invention.

2A-2D are diagrams showing the results of electron microscopy of the structures shown in Figs. 1B-1E of Example 1 of the present invention, respectively.

3A-3C are diagrams showing the results of energy scattering spectrum analysis of the structures shown in Figs. 1B, 1D, and 1E of Example 1 of the present invention, respectively.

Fig. 4 is a graph showing the measurement results of the penetration characteristics of the structures shown in Figs. 1B, 1D, and 1E of the first embodiment of the present invention.

Fig. 5A is a graph showing the results of reflectance of the structures shown in Fig. 1B and Fig. 1E of the first embodiment of the present invention.

Fig. 5B is a graph showing the results of reflectance of a gallium nitride substrate not coated with a ruthenium dioxide nanotube.

11. . . Substrate

12. . . Zinc oxide nanowire

13. . . Cerium oxide film

14. . . Ceria nanotube

Claims (22)

A method for preparing a nano tube anti-reflection layer, comprising the steps of: (A) providing a substrate; (B) forming a plurality of nanowires standing on the substrate; (C) forming a coating layer on the nanowires a surface; (D) removing a portion of the cladding layer to reveal the top ends of the nanowires; and (E) removing the nanowires to form a plurality of nanotubes standing upright on the substrate. The preparation method of claim 1, wherein the step (A) further comprises a step (A1) of forming a seed layer on the surface of the substrate. The preparation method according to the first aspect of the invention, wherein the substrate of the step (A) is selected from the group consisting of: a glass substrate, a quartz substrate, a semiconductor substrate, a transparent conductive coated glass substrate, a ceramic substrate, a metal substrate, and a polymer material. A substrate, a sapphire substrate, and a substrate on which an electronic component is provided on the surface, and a group formed thereof. The preparation method according to claim 2, wherein the material of the seed layer is: zinc aluminum oxide (AZO), indium zinc oxide (IZO), gallium zinc oxide (GZO), or zinc oxide. (ZnO), or a combination thereof. The preparation method of claim 1, wherein the part of the step (D) is a method of removing the coating layer by an inductively coupled plasma (ICP) method. The preparation method according to claim 1, wherein the exposed length of the nanowires in the step (D) is 1 μm or less. The preparation method of claim 1, wherein the removing of the nanowire of the step (D) is performed by immersing in a selective solution for the nanowire and the The cladding layer has etch selectivity. The preparation method according to claim 1, wherein the thickness of the nanotubes is from 1 nm to 1000 nm. The preparation method according to claim 1, wherein the length of the nanotubes is 0.5 μm to 10 μm. The preparation method of claim 1, wherein the outer diameter of the nanotubes is 30 nm to 1500 nm. The preparation method of claim 1, wherein the nanowires are zinc oxide-based nanowires. The preparation method according to claim 1, wherein the nanowires are formed by a hydrothermal method. The preparation method of claim 1, wherein the materials of the nanotubes are transparent insulating materials, transparent semiconductor materials, transparent conductive materials or a combination thereof. The preparation method according to claim 1, wherein the materials of the nanotubes are cerium oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), and nickel oxide (NiO). ), InSnO, Indium, Indium, AlZnO, GaZnO, CuBO ₂ , CuAlO ₂ , copper gallium oxide (CuGaO ₂ ), copper indium oxide (CuInO ₂ ), germanium (Si), gallium arsenide (GaAs), tantalum nitride (Si ₃ N ₄ ), tantalum nitride (TaN), tantalum Oxide (HfLaO), titanium telluride (TiSi ₂ ), titanium nitride (TiN), hafnium oxide (HfO ₂ ), or a combination thereof. A nano tube anti-reflection layer comprises: a substrate; a plurality of nano tubes erected on the substrate; wherein the nanotubes have a length of 0.5 μm to 10 μm and an outer diameter of 30 nm to 1500 nm, The wall thickness is from 1 nm to 1000 nm, and the material of the nanotube is a transparent insulating material, a transparent semiconductor material, a transparent conductive material or a combination thereof. The anti-reflection layer of the nanotube according to claim 15 is for providing an anti-reflection function, and the reflectance of the nanotube anti-reflection layer is less than 1.5% for light having a wavelength range of 400 nm to 800 nm. . The nano tube anti-reflection layer according to claim 15, wherein the substrate is selected from the group consisting of a glass substrate, a quartz substrate, a semiconductor substrate, a transparent conductive coated glass substrate, a ceramic substrate, a metal substrate, and a polymer material. A substrate, a sapphire substrate, and a substrate on which an electronic component is provided on the surface, and a group formed thereof. The anti-reflection layer of the nanotube according to claim 15 further comprising a seed layer disposed between the substrate and the plurality of nanotubes. The nano tube anti-reflection layer according to claim 18, wherein the seed layer has a thickness of 10 to 500 nm. The nano tube anti-reflection layer according to claim 15, wherein the plurality of nano tube systems are irregularly distributed, and the plurality of nano tube systems are: each independently arranged in a single arrangement; two or more adjacent Arranged; or both have a single arrangement independently and two or more adjacent arrangements. The nano tube anti-reflection layer according to claim 15, wherein the length of the nanotube is 1 μm to 10 μm. The nano tube anti-reflection layer according to claim 15, wherein the materials of the nanotubes are cerium oxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), zinc oxide (ZnO), Nickel oxide (NiO), indium tin oxide (InSnO), indium zinc oxide (InZnO), aluminum zinc oxide (AlZnO), gallium zinc oxide (GaZnO), copper boron oxide (CuBO ₂ ), copper aluminum oxide (CuAlO ₂ ), copper gallium oxide (CuGaO ₂ ), copper indium oxide (CuInO ₂ ), germanium (Si), gallium arsenide (GaAs), tantalum nitride (Si ₃ N ₄ ), tantalum nitride (TaN) ), niobium oxide (HfLaO), titanium telluride (TiSi ₂ ), titanium nitride (TiN), hafnium oxide (HfO ₂ ), or a combination thereof.