TWI339221B - Method for preparing nano metallic particles and method for preparing carbon nanotubes and method for preparing light-emitting device using the same - Google Patents

Description

1339221 IX. Description of the Invention: [Technical Field] The present invention relates to a method for preparing a nano metal particle, a method for preparing the same, and a method for preparing the same, and particularly for Method for preparing nano metal particles for reducing metal ions in a mineral process and preparation method thereof, and method for preparing the same. [Prior Art]

According to different principles, researchers have developed a variety of nano metal particle array technologies, such as electron beam writing, anodized aluminum template, microcontact printing, and agglomerated polymer template. Electron beam engraving (see: j. Mater. Res., ν〇ι· 16, p3246, 2〇〇1) Although the nano metal particles can be implanted with precision, the writing process is quite time consuming and unsuitable. Efficiency and large-scale production process. In addition, the electron beam writing method must also use a complicated exposure lithography process, so that the mass production and large-area manufacturing cost are quite expensive.

The anodic oxidation method (see: Appl· Phys. Lett., Vol. 75 P367, 1999) uses a pre-made mold to emboss a small cylindrical hole array on a high-purity aluminum substrate and then pattern this surface. The aluminum substrate is immersed in the electroless plating solution to serve as an anode, and single crystal deposition of alumina is performed. Since the surface of the aluminum substrate has a circular hole, the epitaxial speed of the alumina is different, so that a cylindrical array of holes can be formed. However, the anodized aluminum stencil method can only be applied to a pure substrate, and the grown alumina needs to be microcontacted in a high temperature chemical solution (see: Appl. Phys Lett., 76, 2071, 2000).

U4580.DOC 1339221 ' Using a microlithography electroforming method (LIGA) to make a mold (as a stamp), and using a solution containing a metal catalyst as an ink cartridge, and then (4) cover the stamp (t) to print the metal catalyst solution On the surface of the substrate. However, the microcontact printing method is limited to the scale of the conventional LIGA process, and the metal catalyst cannot be used as a nano-scale array (only for micron arrays). In addition, microcontact printing is also prone to localized metal buildup. The group-linked polymer template method (see: 曰本专利 Publication JP2003342012-A and US Patent Publication No. US 20030185985-A1) is formed by patterning a substrate on a substrate by self-assembly of a cluster-linked polymer, and utilizing ultraviolet light ( UV) or reactive ion etching (RIE) selectively etches one of the components of the coalescent polymer and transfers the self-assembled pattern to the next layer of material. However, in order to increase the aspect ratio of the pattern, it is necessary to use 曰 - different materials as the transfer layer and multiple transfer procedures to increase the aspect ratio of the hole structure to an applicable range. After completing the aspect ratio hole, 'deposition technique is used to deposit the metal medium into the hole of high aspect ratio, φφ finally wash away the transfer layer on the substrate, and the nano metal particles are formed on the nano hole in the substrate. in. The group-linked polymer template method is similar to the half-body exposure lithography process, which utilizes a multi-layer structure and etch rate difference, so that the transfer process is too complicated and the production cost is relatively high, so it has no industrial application value. SUMMARY OF THE INVENTION The present invention provides a method for preparing a nano metal particle for reducing metal ions by an electroplating process, a method for preparing the carbon nanotube, and a method for preparing the same. (.S)

114580 DOC 1339221 The preparation method of the nano metal particles of the present invention is to immerse a conductive substrate in a plating solution containing metal ions, and then perform an electroplating process to reduce the metal ions to form nano metal particles on the conductive substrate. Above. The carbon nanotube of the present invention is prepared by immersing a conductive substrate in a plating solution containing metal ions, and performing an electroplating process to reduce the metal ions to form nano metal particles on the conductive substrate. Thereafter, using the nano metal particles as a catalyst, a chemical vapor deposition process is performed to form a carbon nanotube on the conductive substrate.

The light-emitting device of the present invention is prepared by immersing a conductive substrate in a plating solution containing metal ions, and performing an electroplating process to reduce the metal ions to form nano metal particles on the conductive substrate. Next, using the nano metal particles as a catalyst, a chemical vapor deposition process is performed to form a carbon nanotube on the conductive substrate. Thereafter, a phosphor is formed above the carbon nanotubes. The conventional nano metal particle array technology has the disadvantages of complicated process and high cost in production time. The invention provides a preparation technology of a nano metal particle which is relatively straightforward, low-cost and has a large margin of size adjustment, and does not require complicated fabrication procedures, and only needs to be surface-treated on a conductive substrate (for example, using a plasma bombardment). Conductive substrate surface). It is claimed that the surface roughness of the surface-treated conductive substrate varies with position on the nanometer scale, and the present invention further designs the potential applied by the electroplating process near the standard reduction potential interval of the metal ion to control the nucleation point. When the nucleation is generated, the number of turns of the electroplating process can be adjusted to control the growth size of the subsequent nano metal particles, so that the size of the implanted conductive substrate can be arbitrarily controlled.

1I4580.DOC (S > -8- 1339221 nano metal particles. In addition, if a conductive region/non-conductive region is formed on a conductive substrate in advance using lithography, the present invention can produce a more diverse nano metal. Particle array layout.

Fig. 1 (a) and Fig. 1 (b) illustrate a method of preparing the nano metal particles 丨6 of the present invention. In the preparation method of the present invention, a conductive substrate 12 is immersed in a plating solution 20 containing metal ions 22, and then subjected to an electroplating process (for example, a cyclic potential plating process) to reduce the metal ions 22 to form nano metal particles 丨6. Above the conductive substrate 12. Preferably, the nano metal particles 16 have a size between 1 nm and 150 nm. The conductive substrate 12 may include indium tin oxide (ITO) having a lattice size of 5 nm to 500 nm, and the plating solution 2 may contain a sulphuric acid, nickel sulfate or nickel vapor, and the nano metal particles 16 may be nickel metal particles. Further, the plating solution 2 may be a magnetic metal ion such as iron ion or cobalt ion, and the nano metal particle 16 may be a magnetic metal particle such as an iron metal or a cobalt metal.

Referring to FIG. 1(b), the conductive substrate 12 may be formed by a lithography technique in advance to form a plurality of conductive regions 14 and non-conductive regions 14A, and the nano metal particles 16 are selectively grown over the conductive regions 14A. The surface roughness of the conductive region 14 of the conductive substrate 12 is preferably on the nanometer scale (e.g., between 5 nm and 10 microns). In addition, if the surface roughness of the conductive substrate 12 is too small, the present invention may perform a surface roughening process (for example, a polishing process or a plasma bombardment process) on the surface of the conductive substrate 12 before performing the cyclic potential plating process. The surface roughness of the conductive substrate 12 is made to be on the nanometer scale. Figures 2(a) to 3(c) illustrate surface roughness versus nucleation and growth

"4580 D〇C -9- 1339221 .

The influence of the (growing) mechanism. Since the surface roughness of the conductive substrate 12 is changed at a nanometer scale with position, the reduction reaction of the metal ions 22 selectively grows on a specific surface in a space of a nanometer scale, for example, the conductive substrate 12 ITO grain edge. The present invention can control the nucleation sites by applying a potential near the standard reduction potential interval of the metal ion 2 2 by applying a potential. When nucleation is generated, then the number of turns can be used to control the subsequent crystal growth to obtain nano metal particles 16 having a relatively uniform size as shown in Figs. 2(a) and 3(a). Thus, in the present invention, the nano metal particles 丨6 whose pitch and size can be controlled can be prepared arbitrarily on the surface-treated conductive substrate 12. In contrast, if the electroplating reaction is carried out on a fairly flat metal surface, such as a highly flat copper surface prepared by a ruthenium plating technique, since the surface roughness is relatively small, the reduction reaction of the metal ion 22 is almost performed during the electromineral reaction. There is no "position selectivity" on the flat surface of copper metal, even stacked on a layer of atoms, so that the prepared nano metal particles 16 can not be implanted at the nanometer spacing] Figure 2 (b) , 3(b) and Figure 3(c).

Figures 4(a) and 4(b) illustrate the effects of plating mode on nucleation and growth mechanisms. Fig. 4(a) illustrates the preparation of nano metal particles 16 by a cyclic potential plating process which selectively grows nano metal particles 16 at the grain edges of the conductive substrate 12. Relatively, if a conductive substrate 12' having the same surface roughness distribution is used, but a different plating mode (e.g., electroplating reaction using direct current) is employed, it is easy to cause uneven distribution of nucleation sites, resulting in local local aggregation of the metal. Since the activation of the key reaction requires the electromotive system's potential or potential (v〇itage) to reach the reduction potential of the metal to be bonded 'however' the electroacupuncture 2 contains different concentrations of species (Specie) and 114580 .DOC -10- 1339221 . The “mass transfer” also affects the progress of the electro-recording reaction. Therefore, the electroplating system uses direct current and cannot effectively control the electroplating reaction occurring in the plating solution (including plating). Quantity and position), thus it is easy to make the nucleation point unevenly distributed, resulting in 丨ocal aggregation, as shown in Figure 4(b)**

5(a) to 6(b) illustrate the influence of the surface structure of the conductive substrate 12 on the nucleation and growth mechanism. Fig. 5(a) shows that the surface structure after sputtering silver (Ag) on a wafer has a relatively flat surface structure, so that when the nickel plating reaction is performed, the reduction reaction of the metal ions 22 is hardly "position selectivity" The ground is carried out on the flat surface of the silver metal as shown in Fig. 5(b). In particular, nickel metal is formed on the flat surface of silver metal even by layer-by-layer atomic stacking, so that the recorded metal cannot be implanted at a nanometer pitch, as shown in Fig. 3(b) and Fig. 3(c). Fig. 6(a) shows the surface structure after gold plating (Au) on a wafer. It can also be observed that the reduction uniformity of the metal ions 22 is quite high, and the metal layer is almost formed by layer-by-layer atomic stacking. Nano metal particles distributed at intervals of tens to hundreds of nanometers are formed as shown in Fig. 6(b).

Fig. 7 is a view showing an electron image of the surface-treated conductive substrate 2 of the present invention. Indium tin oxide (ITO) of the conductive substrate 12 has a surface roughness of a nanometer scale. 8(a) to 8(c) are diagrams showing an electron image of the nano metal particles 16 prepared by the cyclic potential plating method of the present invention, the magnifications of which are respectively 5 〇 ' 10,000 times and 50 _ times. According to the present invention, the surface of the conductive substrate 12 after surface treatment (having a conductive region 14Α/non-conductive (four) domain 14β) is subjected to a cyclic potential plating method, and the system is subjected to a two-turn cycle for recording metal ions 22 by electricity (four)-ΟΜΙΟ volts. The reduction reaction can be obtained with a pitch distribution of (10) to 2

I14S80.DOC -11· 1339221 Nickel nano metal particles 16 between meters and having a diameter of about 60 nm. Fig. 9 (4) to Fig. 9 (4) illustrate an electron image of the nano metal particles 16 prepared by the cyclic potential electric key method of the present invention, the magnifications thereof being 2, _, 10,000 and 50, _ times, respectively. According to the present invention, the surface of the conductive substrate 12 after the surface treatment (having the conductive region 14A/non-conductive region 14B) is subjected to a cyclic potential plating method, and the metal ion is recorded at a potential interval of 〇6 to _075 volts for 5 turns. In the reduction reaction of 22, a town nanoparticle 16 having a pitch distribution of about 120 nm in diameter to (7) (9) nm can be obtained. * The embodiment shown in Fig. 8(4) to Fig. 9(e) shows that the control window of the present invention can be obtained by using the surface-treated conductive substrate 12 in combination with the plating mode control to obtain the pitch distribution and the diameter of the control window in the tens to hundreds of nanometers. Rice nanometer particles 丨6. Further, Fig. 10(a) to Fig. 1(c) illustrate an electron image of the carbon nanotube prepared by the present invention, the magnifications thereof being 200 times, 5, 〇〇〇 times and 1 〇〇, 000 times, respectively. In the present invention, the nano-particles 16 are formed on the conductive substrate 12 by cyclic potential plating using the conductive substrate 丨 2 of FIG. Thereafter, a plasma-enhanced chemical vapor deposition process was carried out using the nano metal particles φφ as a catalyst to prepare a nano-stone with an average diameter of about 30 nm, a uniform structure and a straight shape. In particular, the reactive gas of the plasma enhanced chemical vapor deposition process may comprise acetylene and ammonia at a reaction pressure of about 丨_1 〇 尔 (r〇rr). Figure (a) and Figure 11 (b) illustrate a light-emitting element 3〇 prepared by the present invention which is designed as a diode and can be used as a backlight or display. In the present invention, a plurality of spacers 24 are formed on the carbon nanotubes 18, and a fluorescent substrate 26 (including a transparent conductive substrate and a fluorescent substance) is formed on the spacers 24 to complete the light-emitting elements. 3〇. When a predetermined voltage is applied (

1H580.DOC -12- 1339221, for example, 350 volts) between the conductive substrate 12 and the fluorescent substrate 26, the carbon nanotube 18 on the conductive substrate 12 will emit electrons due to the tip discharge effect, which bombards the fluorescent light The phosphor material of the substrate 26 generates a light beam as shown in Fig. H(b).

Figure 12 illustrates a light-emitting element 40 prepared in accordance with the present invention in a tri-polar design. The present invention can form a dielectric block 32 and a conductive block 34 between the conductive substrate 2 and the spacer 24, thereby having three conductive ends (ie, the conductive region 34, the fluorescent substrate 26, and the conductive substrate 12). ), as shown in Figure 12.

The conventional nano metal particle array technology has the disadvantages of complicated process and high cost in production time. The invention provides a preparation technology of a nano metal particle 16 which is relatively straightforward, low-cost and has a large margin of size adjustment. It does not require complicated fabrication procedures and only needs to be surface-treated on the conductive substrate 12 (for example, using electricity). The slurry bombards the surface of the conductive substrate). It is claimed that the surface roughness of the surface-treated conductive substrate 12 varies with position on the nanometer scale, and the present invention further designs the potential value applied by the electroplating process near the standard reduction potential interval of the metal ion 22, thereby controlling the formation. Nuclear point. After the nucleation is formed, the number of turns of the electroplating process can be adjusted to control the growth size of the subsequent nano metal particles 丨6, so that the size-controlled nanometer can be arbitrarily implanted on the surface-treated conductive substrate 丨2. Metal particles 丨6. In addition, if the conductive region 14A/non-conductive region is formed on the conductive substrate 12 by using lithography, the present invention can produce a more diverse array of nano metal particle arrays. In addition, in order to avoid the shielding effect of field emission, the carbon nanotubes need to be separated by a predetermined distance (depending on the length of the carbon tube, and the ratio of tube length to spacing is about 1:1 or 1:2 in the literature). Separate. In general, the polymer itself

I14580.DOC • 13- 1339221 . The distance between assembly and fabrication is difficult to exceed 100 nm, so the application range β is limited. In contrast, the present invention can set the distance between the conductive region 丨4Α/non-conductive region 丨4Β to ββ. The spacing between the meters and the hundreds of nanometers is not limited by the shielding effect of field emission.

The technical and technical features of the present invention have been disclosed above, but those skilled in the art will be able to make various substitutions and modifications without departing from the spirit and scope of the invention. Therefore, the scope of the invention is not limited by the scope of the invention, and the invention is intended to be embraced by the appended claims. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1(a) and FIG. 1(b) illustrate a method of preparing a nano metal particle of the present invention; FIGS. 2(a) to 3(c) illustrate surface roughness versus nucleation and growth mechanism. Figure 4 (a) and Figure 4 (b) illustrate the effect of plating mode on nucleation and growth mechanism; Figure 5 (a) to Figure 6 (b) illustrate the effect of surface structure of the conductive substrate on nucleation and growth mechanism Figure 7 is a view showing a surface electron image of the surface-treated conductive substrate of the present invention; / Figures 8(a) to 8(c) illustrate an electron image of the nano metal particles prepared by the cyclic potential plating method of the present invention; 9(a) to 9(c) are diagrams showing an electron image of nano metal particles prepared by the cyclic potential plating method of the present invention; FIGS. 10(a) to 1(c) illustrate the carbon carbon prepared by the present invention. An electron image of the tube; / Figures 11(a) and 11(b) illustrate a dipole light-emitting element prepared by the present invention;

iM580.DOC -14- 1339221 Figure 1 2 illustrates a three-pole light-emitting element prepared by the present invention. [Main component symbol description] 12 Conductive substrate 14A Conductive area 14B Non-conductive area 16 Nano metal particles 18 Carbon nanotubes 20 Electroplating solution 22 Metal ions 24 Spacer 26 Glow substrate 30 Light-emitting element 40 Light-emitting element

II4580.DOC - 15 *

Claims (1)

1339221 Q 095 丨 41252 Patent Application Serial No. Patent Application (December 1999) 】 A method for preparing nano metal particles, comprising: performing a surface roughening process on the surface of a conductive substrate to make the conductive substrate The surface roughness is on the nanometer scale; 》the bubble is also fused to the conductive substrate in a plating solution of the current 屈3 生3 genist ion and into the 4 亍 electric ore process to return the genus T- 疋The squid ion forms a nano metal particle on the conductive substrate. 2. According to the preparation method of the nano metal particles of claim 1, the surface roughness of the plate is on the nanometer scale. 3. According to the preparation method of the nano metal particles of claim 2, the sugar content is between 5 nm and 1 μm. 4. According to the preparation method of the nano metal particles of the request item, the plate has a conductive region and a non-conductive region. 5. According to the preparation method of the nano metal particles of the claim, the plate comprises a tin oxide. 6. Preparation method of nano metal particles according to claim 1 Sub-system magnetic metal ions. The patent application wherein the surface of the conductive group is thick, wherein the conductive group is the conductive group, wherein the metal is away from the metal, wherein the metal is thicker than the surface thereof, and the metal is electroplated, wherein the nano gold is in accordance with the request The preparation method of the nano metal particles is a ferrite ion, a cobalt ion or a nickel ion. 8. The preparation method of the nano metal particles according to the request item is a polishing process or a plasma bombardment process. 9. The method for preparing nano metal particles according to claim 1 is a cyclic electric potential plating process. 10. Preparation of nano metal particles according to the request item; genus particle size ranging from 1 nm to 150 nm I I4580> REV.DOC 1339221 II · A method for preparing a carbon nanotube comprising: Conducting a surface roughening process on the surface of the conductive substrate such that the surface of the conductive substrate has a coarseness on the nanometer scale; soaking a conductive substrate in a plating solution containing metal ions; and introducing a plating process to reduce the metal ions Forming a nano metal particle on the conductive substrate; and performing a chemical vapor deposition process using the nano metal particle as a catalyst to form a carbon nanotube on the conductive substrate. 12. The method for preparing a carbon nanotube according to claim U, wherein the surface of the conductive substrate is in a nanometer scale β. 13. The method for preparing a carbon nanotube according to claim 12, wherein the surface is coarse The degree of seam is between 5 nm and 1 μm. η. The method of preparing a carbon nanotube according to claim η, wherein the conductive substrate has a conductive region and a non-conductive region. 15. The method for preparing a carbon nanotube according to claim η, which comprises indium tin antimonide. Soil 匕 匕 16.2 The method of preparing a nano tube of claim U, wherein the metal ion captures a magnetic metal ion. The method for preparing a carbon nanotube of claim η, wherein the metal ion is an iron ion, a cation or a recording ion. :, 18. Preparation of the carbon nanotube according to the request item η - polishing process or plasma is the process of the shot. , the surface granulation process according to the preparation method of the carbon nanotubes, wherein a cyclic potential plating process. ^ '一一程系20. According to the preparation of the carbon nanotubes of the request item i to go to the nano metal U4580-REV.DOC 1339221 sub-size is between 1 nm to 丨 5 〇 nanometer between. 21. A method of fabricating a light-emitting device, comprising: performing a surface roughening process on a surface of a conductive substrate such that a surface of the conductive substrate has a coarseness on a nanometer scale; soaking the conductive substrate in a plating containing metal ions In the liquid; performing an electroplating process to form nano metal particles on the conductive substrate; using the nano metal particles as a catalyst, performing a chemical vapor deposition process to form a carbon nanotube on the conductive substrate; and forming A fluorescent substance is above the carbon nanotubes. 2. The method of producing a light-emitting element according to claim 21, wherein the surface roughness of the conductive substrate is on a nanometer scale. 2. The method of producing a light-emitting element according to claim 2, wherein the surface roughness is between 5 nm and 10 μm. 24. The method of fabricating a light-emitting element according to claim 21, wherein the conductive substrate has a conductive region and a non-conductive region. 25. The method of producing a light-emitting element according to claim 21, wherein the conductive substrate comprises indium tin oxide. 26. The method of producing a light-emitting element according to claim 21, wherein the metal ion is a magnetic metal ion. 27. The method of producing a light-emitting element according to claim 21, wherein the metal ion is iron ion, cobalt ion or nickel ion. 28. The method of producing a light-emitting element according to claim 21, wherein the surface roughening process is a polishing process or a plasma bombardment process. The method of producing a light-emitting element according to claim 21, wherein the electroplating process is a cycle electroplating process of 1I458〇.revd〇C 1335221. The method of producing a light-emitting element according to claim 21, wherein the nano metal particles have a size of between 1 nm and 150 nm. 114580.REV.DOC -4-