TW201615536A - Method for manufacturing metallic compound nanotube arrays - Google Patents

Abstract

The present invention provides a method for manufacturing metallic compound nanotube arrays. The method includes following steps: providing a nanowire-template; forming a plurality of nanorods, wherein its core is the nanowire and its shell is metallic compound; performing a first selective etching; performing a second selective etching; and performing a third selective etching. The nanowire-template includes a plurality of nanowires formed as an array and a top end of each of the nanowires is covered by a polymer mask. The first selective etching is to remove the excess metallic material from a surface of each of the nanorods; the second selective etching is to remove the polymer mask from the top end of each of the nanowires; and the third selective etching is to remove each of the nanowires from each of the nanorods and leave the metallic compound as the shell, thereby to manufacture metallic compound nanotube arrays.

Description

Method for manufacturing metal compound nanotube array

The invention relates to a method for manufacturing a nanotube array, in particular to a method for manufacturing a metal compound nanotube array.

The nanotube is a nanometer-sized component that has new properties that cannot be found in the block state and can be applied to various fields. For example, carbon nanotubes can be used in flat display panels or in the field of fuel cells. In addition, wiring materials that can be made with ultra-fine wiring by using a nanotube can not be realized by the prior art.

However, in the manufacturing technology of the nanotubes, it is often necessary to first provide a template having a plurality of through holes, and then form a gold (Au) layer as a cathode by vapor deposition on the surface of the template, and use an electrochemical method to make the metal using an electrolytic solution. The compound forms a nanotube on the through-hole wall surface of the template. However, the film thickness of the nanotube formed by the electrochemical method is difficult to control and requires a long reaction time.

Therefore, how to improve the manufacturing method of the nanotubes, the film thickness of the nanotubes can be effectively controlled, and the plurality of nanotubes can be accurately positioned and arrayed, which will be an urgent research technique.

The invention relates to a method for manufacturing a metal compound nanotube array, which utilizes a nanowire template made of a self-assembled nanosphere array, so that the nanowires can be collimated and arranged in an orderly array, and then arranged. The metal layer is coated on the surface of the polymer mask and the nanowire to form a metal compound nano-column structure in which the core is a nanowire and the core shell is a metal compound, and then multiple selective etching is performed to remove the excess metal layer. The polymer mask and the core nanowire are used to prepare a collimated array of nanotubes on the substrate without using expensive machine equipment and complicated semiconductor lithography processes.

The invention provides a method for manufacturing a metal compound nanotube array, comprising the steps of: providing a nanowire template, the nanowire template comprising a substrate and a plurality of nanowires grown thereon and arranged in an array, and A polymer mask is arranged on the top of each nanowire; a metal layer is coated on each polymer mask and the surface of each nanowire to be annealed to form a core of nanowires and a core shell of metal a metal compound nanocolumn structure of a compound; performing a first selective etching using a first etching material to remove an excess metal layer on the surface of each metal compound nanocolumn structure; performing a second selective etching, Removing each of the polymer masks using a second etch material; and performing a third selective etch using a third etch material to remove the nanowires of each core and leaving a core shell to form a Metal compound nanotube array.

By the implementation of the present invention, at least the following advancements can be achieved: first, a collimated array of nanotubes can be fabricated; and second, the thickness of the nanotubes can be accurately controlled.

In order to make those skilled in the art understand the technical content of the present invention and implement it, and according to the disclosure, the patent scope and the drawings, the related objects and advantages of the present invention can be easily understood by those skilled in the art. The detailed features and advantages of the present invention will be described in detail in the embodiments.

10‧‧‧Nami line template

11‧‧‧Substrate

12‧‧‧Nami Line

13‧‧‧ Polymer mask

20‧‧‧Substrate

21, 21'‧‧‧Nami Ball

30‧‧‧metal layer

31‧‧‧Metal compounds

D‧‧‧ gap

L‧‧‧ length

T‧‧‧ thickness

1 is a flow chart of a method for manufacturing a metal compound nanotube array according to an embodiment of the present invention; FIG. 2 is a schematic diagram of a nanowire template according to an embodiment of the present invention; and FIG. 3 is a diagram of an embodiment of the present invention. A flow chart of a method for manufacturing a rice noodle template; FIG. 4A is a schematic view showing a self-assembled nanosphere array formed on an upper surface of a substrate according to an embodiment of the present invention; and FIG. 4B is a modified nanosphere diameter according to an embodiment of the present invention; FIG. 4C is a schematic perspective view of a nanowire template according to an embodiment of the present invention; FIG. 5 is a schematic view showing a metal layer covering a polymer mask and a surface of a nanowire according to an embodiment of the present invention; 6 is a schematic view of the structure in FIG. 5 after annealing; FIG. 7 is a schematic view of the structure in FIG. 6 after the first selective etching; and FIG. 8 is the second time in the structure in FIG. A schematic view after selective etching; and FIG. 9 is a schematic view of the structure of FIG. 8 after a third selective etching.

As shown in FIG. 1, the embodiment provides a metal compound nanotube A method of manufacturing an array, comprising the steps of: providing a nanowire template (step S10); forming a metal compound nanocolumn structure (step S20); performing a first selective etching (step S30); performing a second selectivity Etching (step S40); and performing a third selective etching (step S50).

Providing a nanowire template (step S10): as shown in FIG. 2, the nanowire template 10 includes a substrate 11 and a plurality of nanowires 12 grown on the substrate 11 and arranged in an array, and The top end of each nanowire 12 has a polymer mask 13.

As shown in FIG. 3, the method for manufacturing the nanowire template 10 includes the steps of: forming a self-assembled nanosphere array on a surface of the substrate (step S11); modulating the diameter of the nanosphere (step S12); Etching (step S13).

Forming a self-assembled nanosphere array on the surface of the substrate (step S11): as shown in FIG. 2 and FIG. 4A, the material of the substrate 20 may be a single crystal germanium or a polycrystalline germanium, for example, a germanium crystal in the (001) direction. The material of the substrate 20 may be gallium (Ga) or aluminum oxide (Al ₂ O ₃ ), and the material of the manufactured nanowire 12 is also a single crystal germanium, polycrystalline germanium, gallium or aluminum oxide. Through the nanosphere self-assembly technology, the nanospheres 21 having a diameter between 300 and 5,000 nanometers are arranged on the upper surface of the substrate 20 in a large-area ordered array of nanospheres, wherein the nanospheres are self-assembled. The technology has been a conventional technique and will not be further described herein.

Modulating the diameter of the nanosphere (step S12): as shown in FIG. 4B and FIG. 5, the diameter of the nanosphere 21' can be modulated by plasma etching, and the diameter of the nanosphere 21' can be The reduction is such that the gap D between the adjacent nanospheres 21' is greater than twice the thickness T of the metal layer 30, wherein the metal layer 30 is a material to be subsequently applied to the surface of the nanowire 12, and the diameter is adjusted. The nanosphere 21' is used as a polymer mask 13 for subsequent etching.

Etching (step S13): before etching (step S13), the gold film may be vapor-deposited on the substrate 20 and the nanosphere 21' by an electron gun evaporation system, followed by hybrid etching as shown in FIG. 4C. The solution is subjected to wet etching or RIE dry etching at a temperature of 20 ° C, wherein a gold film can be used to assist in the progress of the catalytic etching. When etching is performed, no portion of the nanosphere 21' as the polymer mask 13 will be etched, and a plurality of nanowires 12 arranged in an array are etched on the substrate 20, as the etching time increases. The length of the nanowire 12 will also increase, wherein the length L of the nanowire 12 is from 0.7 micrometers to 3 micrometers.

The mixed etching liquid includes hydrogen peroxide, hydrofluoric acid and deionized water, wherein the volume mixing ratio of hydrogen peroxide, hydrofluoric acid and deionized water can be 1:1:1, 1:8:12~24 or 1:4:18 The concentration of hydrogen peroxide was 35% by weight, and the concentration of hydrofluoric acid was 49% by weight.

Since the nanospheres 21 as the polymer mask 13 are arranged on the substrate 20 in an orderly manner by self-assembly technology, the etched nanowires 12 are also aligned and arranged in an orderly manner, which is very helpful. In the subsequent manufacturing process of the nano column or the nanotube, the alignment of the nano column or the nanotube is ensured. For ease of understanding, the portion of the substrate 20 after the etching is further defined as the substrate 11, and the nanowires 12 are arranged in an array on the upper surface of the substrate 11.

A metal compound nanocolumn structure is formed (step S20): as shown in Fig. 5, which shows a state in which the metal layer 30 is coated on the nanowire template 10, wherein the metal layer 30 may be a nickel metal layer. This step may use a coating system or an evaporation system to uniformly coat the metal layer 30 on the surface of each of the polymer masks 13 and the side surfaces of each of the nanowires 12, in the process of coating the metal layer 30. The nanowire template 10 can be at a specific angle with the coating source or the evaporation source to make the metal use the omnidirectional angle The layer 30 is uniformly plated onto the surfaces of the polymer mask 13 and the nanowire 12.

As shown in Fig. 6, annealing is further carried out by introducing nitrogen gas into a high-temperature furnace and annealing at a temperature of 200 ° C to 1,000 ° C to form a metal compound 31 on the surface of the nanowire 12 . Thereby, a metal compound nanocolumn structure is formed in which the core of the metal compound nanocolumn structure is the nanowire 12, and the core shell is the metal compound 31.

Since the metal layer 30 is coated on the nanowire template 10 using a coating system or an evaporation system, the core shell thickness of the metal compound nanocolumn structure (i.e., the thickness of the metal compound 31) can be controlled, and on the substrate 20 When the material of the nanowire 12 is single crystal germanium or polycrystalline germanium, the metal compound 31 may be a metal halide.

Performing a first selective etching (step S30): as shown in FIG. 7, after completing the preparation of the metal compound nanocolumn structure (step S20), each metal compound nanocolumn structure is removed using the first etching material The excess metal layer on the surface is, for example, a metal layer coated on the surface of the polymer mask 13. Wherein, the first etching material is nitric acid (HNO ₃ ) or hydrochloric acid (HCl), and the metal layer on the surface of the metal compound nano-column structure refers to the reaction of the metal material with the nanowire 12 material after the thermal annealing step , the remaining metal material. Taking nickel metal and tantalum nanowires as an example, it refers to nickel metal remaining on the surface of the metal compound nanocolumn structure after the reaction of nickel and ruthenium is completed.

Performing a second selective etching (step S40): as shown in FIGS. 7 and 8, after performing the first selective etching (step S30), the second etching material is used to remove the bit in each Each polymer mask 13 on the top of the rice noodle 12 exposes the top of the core portion of the metal compound nano-pillar structure (ie, the nanowire 12), wherein the second etching material may be a polyalkane solvent, for example Tetrahydrofuran (THF), having a carbonyl solvent such as methyl ethyl ketone (MEK), a benzene solvent, for example Toluene or an aromatic solvent such as tetrachloroethylene or ethylene.

Performing a third selective etching (step S50): as shown in FIGS. 8 and 9, after performing the second selective etching (step S40), the third etching material is used to remove each core of the nanometer. Line 12 leaves a core shell (i.e., metal compound 31) to form a metal compound nanotube array. The third etching material may be an ammonium base organic solvent, such as tetramethylammonium hydroxide (TMAH), a strong alkali hydroxide organic solvent, such as sodium hydroxide (NaOH), or a potassium compound organic solvent. For example, potassium hydroxide (KOH) has a concentration of 6 to 13 weight percent (wt%).

The metal compound nanotube array prepared by the present embodiment has the advantages of using the nanosphere self-assembly technology to allow the nanowires 12 to be collimated and ordered on the substrate 11, so that the metal compound nanotubes are also Can be aligned and positioned. Further, since the thickness T of the surface of the polymer mask 13 and the nanowire 12 can be controlled by the metal layer 30, the thickness of each metal compound nanotube in the metal compound nanotube array can be easily controlled.

The embodiments are described to illustrate the features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the present invention and to implement the present invention without limiting the scope of the present invention. Equivalent modifications or modifications made by the spirit of the disclosure should still be included in the scope of the claims described below.

S10‧‧‧ provides nanowire template steps

S20‧‧‧Formation of metal compound nanocolumn structure

S30‧‧‧First selective etching step

S40‧‧‧Second selective etching step

S50‧‧‧A third selective etching step

Claims (14)

A method for manufacturing a metal compound nanotube array, comprising the steps of: providing a nanowire template, the nanowire template comprising a substrate and a plurality of nanowires grown thereon and arranged in an array, and each The top of the nanowire has a polymer mask; a metal layer is coated on each of the polymer mask and the surface of each of the nanowires to be annealed to form a core for the nanowire and a core shell a metal compound nanocolumn structure which is one of metal compounds; performing a first selective etching by removing the metal layer remaining on the surface of each of the metal compound nanocolumn structures using the first etching material; performing the second selection Scratch, which uses a second etch material to remove each of the polymer masks; and a third selective etch that removes the nanowires of each of the cores using a third etch material and leaves The core shell is formed into an array of metal compound nanotubes. The manufacturing method of claim 1, wherein the method for manufacturing the nanowire template comprises the steps of: forming a self-assembled nanosphere array on a surface of a substrate; and modulating the self-assembled nanometer. The diameter of each nanosphere in the array of spheres, wherein each of the nanospheres serves as a polymeric mask; and etching is performed by wet etching or RIE dry at a temperature of 20 ° C using a mixed etching solution Etching, forming a plurality of the nanowires arranged in an array on the substrate. The manufacturing method of claim 1 or 2, wherein the substrate and The material of the nanowire is monocrystalline or polycrystalline, and the metal compound is a metal halide. The manufacturing method according to claim 2, wherein each of the nanospheres has a diameter of 300 to 5,000 nm. The manufacturing method of claim 4, wherein modulating the diameter of each of the nanospheres in the self-assembled nanosphere array reduces the diameter of each of the nanospheres by plasma etching to The gap between adjacent nanospheres is greater than twice the thickness of the metal layer. The manufacturing method according to claim 5, wherein the mixed etching solution comprises hydrogen peroxide, hydrofluoric acid and deionized water, and the volume mixing ratio is 1:1:1, 1:8:12~24 or 1: 4:18, wherein the concentration of the hydrogen peroxide is 35% by weight, and the concentration of the hydrofluoric acid is 49% by weight. The manufacturing method according to claim 1, wherein the nanowire has a length of from 0.7 μm to 3 μm. The manufacturing method of claim 1, wherein the metal layer is a nickel metal layer, and the nickel metal is uniformly coated on each of the polymer masks and each of the nano-coatings by a coating system or an evaporation system. The surface of the rice noodle. The manufacturing method according to claim 1, wherein when annealing is performed, nitrogen gas is introduced into the high-temperature furnace, and the annealing temperature is 200 ° C to 1,000 ° C. The manufacturing method of claim 1, wherein the first etching material is nitric acid (HNO ₃ ) or hydrochloric acid (HCl). The manufacturing method according to claim 1, wherein the second etching material is a polyalkyl solvent, a carbonyl solvent, a benzene solvent or an aromatic solvent. The manufacturing method according to claim 11, wherein the polyalkane solvent is Tetrahydrofuran (THF), the carbonyl-based solvent is methyl ethyl ketone (MEK), the benzene solvent is toluene, and the aromatic solvent is tetrachloroethylene or ethylene. The manufacturing method according to claim 1, wherein the third etching material is an ammonium base organic solvent, a strong alkali hydroxide organic solvent or a potassium compound organic solvent, and the concentration thereof is 6 to 13 weight percent (wt %). The manufacturing method according to claim 13, wherein the ammonium base organic solvent is tetramethylammonium hydroxide (TMAH), and the strong alkali hydroxide organic solvent is sodium hydroxide (NaOH), the potassium compound The organic solvent is potassium hydroxide (KOH).