CN109343166B - Micro-polarizer array based on multiwall carbon nanotubes and manufacturing method thereof - Google Patents

Abstract

The invention discloses a micro-polarizer array based on multi-wall carbon nano tubes and a manufacturing method thereof, wherein the method comprises the following steps: manufacturing a catalyst array; growing a flaky multi-wall carbon nano tube array on the catalyst array; placing the flaky multi-wall carbon nano tube array on a substrate to form a densified multi-wall carbon nano tube film array; etching the multi-wall carbon nano tube film array to obtain a micro-polarizer array in one direction; the above operations were repeated to produce four-directional polarizer arrays, respectively. The invention utilizes the polarization characteristic of the parallel carbon nanotube film to manufacture the parallel carbon nanotube film into the micro-polarization unit, which can effectively solve the problems of complex process, high cost and low efficiency in the prior art.

Description

Micro-polarizer array based on multi-walled carbon nanotubes and its manufacturing method

Technical Field

The present invention relates to the technical field of polarization state measurement, and in particular to a micro-polarizer array based on multi-walled carbon nanotubes and a manufacturing method thereof.

Background Art

Most of the existing micro-polarization arrays use metal wire grid solutions. The nanoscale metal wire grid period and line width have high requirements on process and equipment. The period ranges from tens of nanometers to several microns according to the polarization requirements. Carbon nanotubes are a one-dimensional carbon nanomaterial with excellent mechanical and electrical properties. The diameter of multi-walled carbon nanotubes is only about 2-20 nanometers. Compared with the period size of traditional metal wire grids, it is smaller. On a substrate deposited with a catalyst, a vertically arranged multi-walled carbon nanotube array can be grown by chemical vapor deposition, eliminating the complex and high-cost process of traditional wire grid production. The thickness of the carbon nanotube film determines the extinction ratio of the polarizer. The extinction ratio of a 5-micron thick straight-arranged multi-walled carbon nanotube film in the visible light band is about 30 decibels.

In Chinese invention patent CN101893731A, Zhang Qingchuan et al. proposed a real-time polarization state and phase measurement method based on a pixel polarizer array, and described in detail the measurement method, structural design, working principle, etc. of the polarizer array. However, the patent did not involve the technical issue of the production of a micro-polarization array.

In Chinese invention patent CN103760681A, Dong Fengliang et al. proposed a method for making a micro-polarizer array of metal nano-gratings. The method includes depositing a metal film on optical glass to form a grating substrate, with a film thickness of about 150-250 nanometers; spin-coating a positive electron beam photoresist layer on the substrate surface and drying it, developing the photoresist layer by electron beam lithography to obtain a photoresist pattern; using inductively coupled plasma etching, using the photoresist with the pattern as a mask, etching the metal film layer to transfer the pattern to the metal film. The electron beam lithography method has low efficiency and high requirements for equipment. It is only suitable for single-piece production and cannot be used for mass production.

Summary of the invention

1. Technical issues to be resolved

The object of the present invention is to provide a micro-polarizer array based on multi-walled carbon nanotubes and a manufacturing method thereof, so as to at least partially solve the above technical problems.

(II) Technical solution

According to one aspect of the present invention, there is provided a method for manufacturing a micro-polarizer array based on multi-walled carbon nanotubes, comprising:

making a catalyst array;

growing a sheet-like multi-walled carbon nanotube array on a catalyst array;

placing the sheet-like multi-walled carbon nanotube array on a substrate to form a multi-walled carbon nanotube film array;

Etching the multi-walled carbon nanotube film array to obtain a micro-polarizer array in one direction;

Repeat the above steps to make polarizer arrays in four directions respectively.

In a further embodiment, the making of the catalyst array comprises:

forming a buffer layer on a substrate and performing a drying process;

Spin coating a photoresist layer on the buffer layer and drying the layer;

Covering the photoresist layer with a mask, exposing and developing to obtain a catalyst array pattern;

forming a catalyst layer on the array pattern;

The photoresist layer is removed to obtain a catalyst array.

In a further embodiment, the forming of the catalyst layer is: coating a layer of iron film on the photoresist pattern array by a sputtering process or an electron beam evaporation process.

In a further embodiment, placing the sheet-like multi-walled carbon nanotube array on a substrate comprises: immersing the sheet-like multi-walled carbon nanotube array in an organic solvent, removing the solvent and then performing a drying process.

In a further embodiment, the immersion in an organic solvent is: immersing the sheet-like multi-walled carbon nanotube film in an isopropanol or ethanol organic solvent in a direction parallel to the horizontal plane, and pulling it out along the original direction; the drying treatment is: baking on a hot plate at a temperature of 80-100°C or in an oven for 5-10 minutes.

In a further embodiment, etching the multi-walled carbon nanotube film array comprises:

Spin coating a photoresist layer on the multi-walled carbon nanotube film array and drying the layer;

Covering the photoresist layer with a mask, exposing and developing to obtain a photoresist micro-polarizer array pattern;

Etching the multi-walled carbon nanotube film array to transfer the pattern to the multi-walled carbon nanotube film layer;

The photoresist is removed.

In a further embodiment, the growing sheet-like multi-walled carbon nanotube array is a multi-walled carbon nanotube array that is sequentially arranged by growing using a water-assisted chemical vapor deposition method.

In a further embodiment, when growing the multi-walled carbon nanotube array, the gases introduced include: argon, hydrogen, ethylene, wet argon; or, the gases introduced include: argon, hydrogen, acetylene and wet argon.

In a further embodiment, the manufacturing of polarizer arrays in four directions includes: manufacturing polarizer arrays in four directions of 0°, 45°, 90°, and 135°.

According to another aspect of the present invention, there is provided a micro-polarizer array based on multi-walled carbon nanotubes, comprising:

One or more polarizer units, each polarizer unit includes four polarizers in different directions; wherein the polarizer material is multi-walled carbon nanotubes.

In a further embodiment, the multi-walled carbon nanotube-based micro-polarizer array further comprises:

substrate;

a buffer layer deposited on the substrate;

A patterned catalyst layer is deposited on the buffer layer; wherein the pattern of the catalyst layer is the same as the pattern of the polarizer, and the micro-polarization is grown on the catalyst layer.

In a further embodiment, the polarizer units are polarizers in four directions: 0°, 45°, 90°, and 135°, and are arranged in sequence clockwise to form a 2*2 array.

In a further embodiment, the multi-walled carbon nanotubes are sequentially arranged multi-walled carbon nanotubes.

(III) Beneficial effects

The present invention provides a multi-walled carbon nanotube-based micro-polarizer array and a method for manufacturing the same, which have at least the following beneficial effects:

The material used in the micro-polarizer array of the present invention is carbon nanotubes. As a one-dimensional nanomaterial, carbon nanotubes are light in weight, high in mechanical strength, have perfect hexagonal structure connection, and have excellent ductility, flexibility, transparency, corrosion resistance, and excellent electromagnetic wave absorption characteristics.

Sequentially arranged multi-walled carbon nanotubes show obvious optical and electrical anisotropy characteristics in the axial and perpendicular directions. Sequentially arranged multi-walled carbon nanotube arrays can absorb light waves parallel to the axial direction and transmit light waves perpendicular to the axial direction. The axially arranged carbon nanotube array absorbs light waves whose polarization direction is consistent with its axial direction, and the free electrons in the carbon nanotubes move along the axial direction. When the polarization direction of the incident light is consistent with the axial direction, the electrons in the carbon nanotubes vibrate in the direction of the photon electric field, so that the photon energy is transferred to the electrons in the multi-walled carbon nanotubes, and finally dissipated in the form of heat in the carbon nanotube lattice structure. Utilizing the polarization characteristics of the axially arranged carbon nanotube film and making it into a micro-polarization unit can effectively solve the problems of complex existing processes, high costs, and low efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a 0° mask plate of a catalyst array according to an embodiment of the present invention (the other four angled mask plate units only have different direction angles, and the unit structure dimensions are consistent);

FIG2 is a schematic diagram of a process for manufacturing a four-directional polarizer array according to an embodiment of the present invention;

3 is a schematic diagram of a 0° mask plate of a multi-walled carbon nanotube array according to an embodiment of the present invention (the positions of the mask plates at the other four angles are different, but the unit structure sizes are the same);

FIG4 is a single-cycle manufacturing process flow chart of an embodiment of the present invention (wherein the catalyst layer still exists on the sample after step 4e, but its thickness is 1-2 nanometers, which is negligible compared with other layers and is not shown in the figure);

FIG5 is a schematic diagram of a densification process of a sheet-like multi-walled carbon nanotube according to an embodiment of the present invention;

FIG6 is a flowchart of manufacturing a micro-polarizer array based on multi-walled carbon nanotubes according to an embodiment of the present invention;

FIG. 7 is a diagram showing the growth process of multi-walled carbon nanotubes based on a multi-walled carbon nanotube micro-polarizer array according to an embodiment of the present invention.

DETAILED DESCRIPTION

In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

According to one embodiment of the present invention, a method for manufacturing a micro-polarizer array based on multi-walled carbon nanotubes is provided, as shown in FIG5 , comprising:

making a catalyst array;

growing a sheet-like multi-walled carbon nanotube array on a catalyst array;

Laying the sheet-like multi-walled carbon nanotube array on a substrate to form a densified multi-walled carbon nanotube film array;

Etching the multi-walled carbon nanotube film array to obtain a micro-polarizer array in one direction;

Repeat the above steps to make polarizer arrays in four directions.

In this embodiment, the preparation of the catalyst array includes:

forming a buffer layer on a substrate and performing a drying process;

Spin coating a photoresist layer on the buffer layer and drying the layer;

Covering the photoresist layer with a mask, exposing and developing to obtain a catalyst array pattern;

forming a catalyst layer on the array pattern;

The photoresist layer is removed to obtain a catalyst array.

The mask is a mask for the catalyst array, which contains four pieces, namely arrays in four directions of 0°, 45°, 90°, and 135°. The line width of the rectangular unit determines the thickness of the carbon nanotube film after it is laid down, thus playing a decisive role in the extinction ratio of the micro-polarization array. The pattern size of the mask is determined by the size of the designed polarization array unit. Multiple masks correspond to patterns in multiple polarization directions, a total of four directions of 0°, 45°, 90°, and 135°.

The buffer layer is formed on the substrate by depositing an aluminum oxide film on the substrate by atomic layer deposition process, with a thickness of 10-20 nm. The drying process is baking on a hot plate or in an oven, preferably at a baking temperature of 120-220° C. and for a baking time of 2-60 minutes.

The spin-coated photoresist layer is a layer of extreme ultraviolet positive photoresist that is spin-coated on the aluminum oxide film and dried. The thickness of the photoresist is 0.8-1.6 microns, preferably AZ6112. The drying process is hot plate baking, and when AZ6112 photoresist is used, the baking temperature is 100° C. and the baking time is 60 seconds.

Wherein, when the catalyst array mask is covered on the photoresist layer, and the photoresist carbon nanotube growth array pattern is obtained by exposure and development, the mask corresponds to one of the four different directions, and the corresponding mask is replaced when the polarization array in the next direction is produced. Preferably, the exposure time is 2.3 seconds and the development time is 30 seconds.

The catalyst layer is formed by coating an iron film layer on the photoresist pattern layer by sputtering or electron beam evaporation. According to the quality requirements of multi-walled carbon nanotube growth, the thickness of the iron film layer is 1-2 nanometers.

The photoresist layer is removed by using acetone accompanied by ultrasonic treatment to form a catalyst array. A rectangular catalyst is made by photolithography, and a vertically arranged sheet-like carbon nanotube array can be grown by water-assisted chemical vapor deposition.

In this embodiment, the method of growing a sheet-like multi-walled carbon nanotube array using water-assisted chemical vapor deposition includes: placing a substrate coated with a catalyst array pattern into a quartz tube of a vapor deposition furnace; introducing argon after sealing, and starting to introduce hydrogen after heating to a certain temperature, introducing ethylene or acetylene when the temperature stabilizes at a certain temperature, and then introducing wet argon; starting to grow until carbon nanotubes of sufficient height and volume density are obtained. The method of water-assisted chemical vapor deposition can be used to grow a vertically arranged multi-walled carbon nanotube array. The growth is carried out in a temperature-controlled furnace. Before the growth begins, the sample with the catalyst is placed in the vapor deposition furnace. The gases used to grow the carbon nanotube array include argon, hydrogen, ethylene (acetylene), and wet argon. Timed growth, the growth time determines the height of the carbon nanotube growth, and the maximum height can be several millimeters.

In this embodiment, the step of laying the sheet-like multi-walled carbon nanotube array on the substrate includes: immersing the sheet-like carbon nanotube film in an organic solvent in a direction parallel to the horizontal plane, the organic solvent being isopropanol or ethanol; drying treatment is baking on a hot plate, the baking temperature is 80-100°C, and the baking time is 5-10 minutes; thereby obtaining a densified multi-walled carbon nanotube film array laid on the substrate, and the arrangement direction after laying is determined by the growth array direction. Among them, the laying in this embodiment is that the multi-walled carbon nanotubes grown perpendicular to the base are laid down in a certain direction so as to be parallel to the base.

The carbon nanotube array does not wet in water, but soaks in an organic solvent. The obtained sheet-like carbon nanotube array is immersed in an organic solvent, which can lay the carbon nanotube array down and densify it, while maintaining the characteristics of the array's sequential arrangement. The laying direction is consistent with the direction from the organic solvent, and the pattern can also be made into a trapezoid to guide the carbon nanotubes to fall. The volume fraction of the densified straight-arranged carbon nanotube film can be shrunk from 1% to 50%. After laying down, the densified multi-walled carbon nanotube array film is covered with a layer of photoresist as a mask on the surface of the pattern area that needs to be retained through photolithography technology. Reactive ion etching is used to etch away the area not covered by the photoresist pattern. After washing away the residual glue, a polarizer array in the laying direction can be obtained.

In this embodiment, etching the multi-walled carbon nanotube film array includes:

Spin coating a photoresist layer on the multi-walled carbon nanotube film array and drying the layer;

Covering the photoresist layer with a mask, exposing and developing to obtain a photoresist micro-polarizer array pattern;

Etching the multi-walled carbon nanotube film array to transfer the pattern to the multi-walled carbon nanotube film layer;

The photoresist is removed.

Wherein, a photoresist layer is spin-coated on the multi-walled carbon nanotube film array, the photoresist layer is extreme ultraviolet photoresist, the thickness of which is 6-10 microns, preferably AZ4620, the baking temperature is 100° C., and the baking time is 360 seconds.

The mask is a mask of a multi-walled carbon nanotube array, and the mask used each time should correspond to the mask of the catalyst array used at that time. When AZ4620 is selected, the exposure time is 25 seconds, the development time is 3-5 minutes, and the sample is blown dry with nitrogen after development.

The etching of the multi-walled carbon nanotube film array is carried out by reactive ion etching, using the photoresist layer with the pattern as a mask to etch the multi-walled carbon nanotube film array to transfer the pattern to the multi-walled carbon nanotube film layer. Preferably, the reaction gas is oxygen with a flow rate of 10 sccm and a power of 200W.

The removing of the photoresist is to use acetone to remove the residual photoresist, thereby obtaining a micro-polarizer array in one direction.

In this embodiment, the manufacturing of polarizer arrays in four directions includes: manufacturing polarizer arrays in four directions of 0°, 45°, 90°, and 135°. FIG2 is a schematic diagram of the manufacturing process of polarizer arrays in four directions, wherein FIG2a is the manufacturing of a 0° micro-polarization subarray in the first cycle; FIG2b is the manufacturing of a 45° micro-polarization subarray in the second cycle; FIG2c is the manufacturing of a 90° micro-polarization subarray in the third cycle; and FIG2d is the manufacturing of a 135° micro-polarization subarray in the fourth cycle.

According to another embodiment of the present invention, there is provided a micro-polarizer array based on multi-walled carbon nanotubes, comprising:

One or more polarizer units, each polarizer unit includes four polarizers in different directions; wherein the polarizer material is multi-walled carbon nanotubes.

In this embodiment, the multi-walled carbon nanotube-based micro-polarizer array further includes:

substrate;

a buffer layer deposited on the substrate;

A patterned catalyst layer is deposited on the buffer layer; wherein the pattern of the catalyst layer is the same as the pattern of the polarizer, and the micro-polarization is grown on the catalyst layer.

In this embodiment, the substrate is a transparent material, which may be, but is not limited to, a glass substrate or a silicon dioxide substrate.

In this embodiment, the buffer layer may be, but is not limited to, an aluminum oxide layer, and its thickness is between 10-20 nm according to the quality requirements of carbon nanotube growth.

In this embodiment, the patterned catalyst layer may be a layer of iron film with a thickness of 1-2 nm. The thickness is negligible and is therefore omitted in the drawings.

In this embodiment, the polarizer units are polarizers in four directions: 0°, 45°, 90°, and 135°, and are arranged in sequence clockwise to form a 2*2 array.

In this embodiment, the multi-walled carbon nanotubes are multi-walled carbon nanotubes arranged in sequence.

As a one-dimensional nanomaterial, carbon nanotubes are light in weight, high in mechanical strength, with perfect hexagonal structure connection, excellent ductility, flexibility, transparency, corrosion resistance, and excellent electromagnetic wave absorption properties. The sequentially arranged multi-walled carbon nanotubes show obvious optical and electrical anisotropy in the axial and vertical axes.

The present invention is further described below by an exemplary embodiment, wherein the preparation method comprises:

Step 1: Use a maskless lithography machine to make masks for catalyst arrays in four directions. Figure 1 shows a schematic diagram of a catalyst array 0° mask, where the shaded part is transparent, the unit width is 6 microns, and the spacing is 100 microns. For the other three masks, the length directions of the rectangular units are along the directions of 45°, 90°, and 135°. And a mask for a multi-walled carbon nanotube array, as shown in Figure 3, which is a schematic diagram of a multi-walled carbon nanotube array 0° mask, where the shaded part is transparent, the unit is 5 microns × 5 microns, and the spacing is 8 microns. The other three directions are used to etch the mask to form a multi-walled carbon nanotube array. The micro-polarization unit size is consistent, and the layout is consistent with Figure 2.

Step 2: As shown in FIG. 4 a , an aluminum oxide thin film layer 2 having a thickness of 10 nanometers is deposited on a cleaned silicon dioxide substrate 1 using an atomic layer deposition technique.

Step 3: As shown in Figure 4b, use nitrogen to blow away dust on the sample surface, spin-coat AZ6112 positive extreme ultraviolet first photoresist 3, and form a photoresist pattern for carbon nanotube growth after exposure and development, and bake it on a 100°C hot plate for 60 seconds. Considering the iron catalyst 4 lift off and pattern effect, the photoresist thickness should be about 1 micron. In each cycle, the catalyst array mask with different angles is replaced until all four angles are completed.

Step 4: As shown in FIG4c, a layer of 1.5 nanometer iron catalyst 4 is sputtered on the surface of the sample with the photoresist pattern using magnetron sputtering technology. After that, acetone is used to clean with ultrasonic cleaning for 1-2 minutes to remove the resist pattern and the iron on the photoresist pattern. After cleaning, the sample is dried with nitrogen gas, and the obtained sample is shown in FIG4d.

Step 5: Grow carbon nanotube 5 array by water-assisted chemical vapor deposition. Put the silicon substrate coated with the catalyst array pattern into the quartz tube (inner diameter 180mm) of the vapor deposition furnace, seal it, and introduce argon gas with a flow rate of 90sccm; heat it to 550℃ and start introducing hydrogen with a flow rate of 50sccm; when the temperature is stable at 760℃, introduce ethylene with a flow rate of 80sccm and wet argon with a flow rate of 9sccm; start timing growth, the growth height of carbon nanotubes is determined by the growth time, and the height of carbon nanotubes obtained after 15 minutes of growth is about 400 microns, and the volume density is about 1%. The growth process is shown in Figure 7, and the grown carbon nanotube sheet array sample is shown in Figure 4e.

Step 6: Lay down the carbon nanotube array to densify it. As shown in Figure 5, keep the carbon nanotube sheet level with the horizontal plane, immerse the carbon nanotube sheet array sample in isopropanol, keep it for a few seconds and then take it out along the immersion direction, and then bake it at 80°C for 10-20 minutes to obtain a densified carbon nanotube film laid down on the substrate.

Step 7: As shown in Figure 4g, use nitrogen to blow away dust on the sample surface, spin-coat AZ4620 positive extreme ultraviolet second photoresist 6, and form a photoresist pattern for carbon nanotube growth after exposure and development, and place it on a 100°C hot plate for baking for 360 seconds. Among them, the carbon nanotube etching and photoresist selection ratio, the photoresist thickness should be above 6 microns. Among them, the multi-walled carbon nanotube array mask is changed at different angles for each cycle until all four angles are completed.

Step 8: As shown in FIG. 4h , the densified aligned carbon nanotube film is etched using reactive ion etching technology, with a power of 200 W and an oxygen flow rate of 10 sccm.

Step 9: As shown in FIG4i , acetone is used to clean and remove the residual glue on the surface of the sample after etching. After cleaning, it is blown dry with nitrogen to obtain a micro-polarization array in one direction.

Step 10: As shown in Figure 2, the production of the micro-polarization array at all four angles of 0°, 45°, 90°, and 135° is completed in four cycles.

Finally, each array unit is a 2*2 multi-walled carbon nanotube polarizer unit, and each polarizer unit is a multi-walled carbon nanotube micro-polarizer array arranged in clockwise order with polarizers in four different directions of 0°, 45°, 90°, and 135°. Its top view is shown in Figure 2d.

It should be noted that this document may provide demonstrations of parameters containing specific values, but these parameters do not need to be exactly equal to the corresponding values, but can be approximated to the corresponding values within an acceptable error tolerance or design constraint. The directional terms mentioned in the embodiments, such as "up", "down", "front", "back", "left", "right", etc., are only reference directions of the accompanying drawings and are not intended to limit the scope of protection of the present invention. In addition, unless the steps are specifically described or must occur in sequence, the order of the above steps is not limited to those listed above, and can be changed or rearranged according to the desired design. In addition, the above embodiments can be mixed and matched with each other or with other embodiments based on design and reliability considerations, that is, the technical features in different embodiments can be freely combined to form more embodiments.

The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. A method for manufacturing a micro-polarizer array based on multi-walled carbon nanotubes, comprising:

fabricating a catalyst array comprising:

Forming a buffer layer on a substrate and drying;

spin-coating a photoresist layer on the buffer layer and drying;

Covering a mask plate on the photoresist layer, exposing and developing to obtain a photoresist pattern of the catalyst array;

Forming a catalyst layer on the photoresist array pattern, wherein the catalyst layer is formed by: plating an iron film layer on the photoresist array pattern through a sputtering process or an electron beam evaporation process, wherein the thickness of the iron film layer is 1-2 nanometers;

removing the photoresist layer to obtain a catalyst array;

Growing a flaky multi-wall carbon nano tube array on the catalyst array;

placing the flaky multi-wall carbon nano tube array on a substrate to form a multi-wall carbon nano tube film array;

Etching the multi-wall carbon nano tube film array to obtain a micro-polarizer array in one direction;

wherein etching the multi-walled carbon nanotube film array comprises:

spin coating a photoresist layer on the multi-wall carbon nano tube film array and drying;

Covering a mask plate on the photoresist layer, exposing and developing to obtain a photoresist micro-polarizer array pattern, wherein the mask plate used each time corresponds to the mask plate of the catalyst array used at the time;

Etching the multi-wall carbon nano tube film array to transfer the pattern to the multi-wall carbon nano tube film layer;

removing the photoresist;

the above operations were repeated to produce a four-directional polarizer array.

2. The method of claim 1, wherein the placing the sheet-like multi-walled carbon nanotube array on a substrate comprises: immersing the flaky multi-wall carbon nano tube array into an organic solvent, and carrying out post-drying treatment.

3. The method for manufacturing a multiwall carbon nanotube-based micro-polarizer array according to claim 2, wherein the organic solvent is: immersing the flaky multi-wall carbon nano tube film in isopropanol or ethanol organic solvent along the direction parallel to the horizontal plane, and extracting along the original direction; the drying treatment is as follows: baking on hot plate or oven at 80-100deg.C for 5-10 min.

4. The method for manufacturing a micro-polarizer array based on multi-walled carbon nanotubes according to any one of claims 1-3, wherein the growing sheet-like multi-walled carbon nanotube array is a multi-walled carbon nanotube array grown by a water-assisted chemical vapor deposition method to form a sequential arrangement.

5. A method for manufacturing a micro-polarizer array based on multi-walled carbon nanotubes according to any of claims 1-3, wherein the growing the sheet-like multi-walled carbon nanotube array comprises: argon, hydrogen, ethylene and wet argon; or the gas is introduced to comprise: argon, hydrogen, acetylene and wet argon.

6. A method of fabricating a multiwall carbon nanotube based micro-polarizer array as recited in any of claims 1-3, wherein the fabricating the four-directional polarizer array comprises: respectively manufacturing polarizer arrays in four directions of 0 degrees, 45 degrees, 90 degrees and 135 degrees.

7. A multiwall carbon nanotube-based micro-polarizer array prepared by the method of any one of claims 1-6, comprising:

one or more polarizer units, each comprising 4 different-direction polarizers; wherein the polarizer material is a multiwall carbon nanotube;

wherein, the thickness of the iron film layer is 1.5 nanometers.

8. The multiwall carbon nanotube-based micro polarizer array of claim 7, further comprising:

A substrate;

A buffer layer deposited on the substrate;

a patterned catalyst layer deposited on the buffer layer; wherein the catalyst layer pattern is the same as the polarizer pattern, and the sheet-shaped multi-walled carbon nanotube array is grown on the catalyst layer.

9. The multiwall carbon nanotube based micro polarizer array of claim 7, wherein the polarizer elements are four-way polarizers of 0 °, 45 °, 90 °, 135 ° and are sequentially arranged clockwise to form a2 x 2 array.

10. The multiwall carbon nanotube-based micro polarizer array of any of claims 7-9, wherein the multiwall carbon nanotubes are sequentially arranged multiwall carbon nanotubes.