Core-shell nano particle for formation of transparent conductive film, and manufacturing method of transparent conductive film using the same

Abstract

Disclosed herein are a core-shell nano particle for formation of a transparent conductive film, a manufacturing method of the core-shell nano particle, and a manufacturing method of a transparent conductive film using the core-shell nano particle and, more particularly, a core-shell structured nano particle consisting of a core including indium or indium oxide and a shell including tin, a manufacturing method of the core-shell structured nano particle, and a manufacturing method of a transparent conductive film including (i) dispersing a core-shell structured nano particle into a solvent to manufacture a coating liquid, (ii) applying the coating liquid onto a substrate to form a coating layer, (iii) drying the coating layer, and (iv) performing an annealing process on the coating layer.

Claims

1. A manufacturing method of a transparent conductive film using a core-shell structured nano particle, the manufacturing method comprising: (i) dispersing core-shell structured nano particles with a core that includes indium and a shell that includes tin into a solvent to manufacture a coating liquid; (ii) applying the coating liquid onto a substrate to form a coating layer; (iii) drying the coating layer; and (iv) sintering the nano particles by performing an annealing process on the coating layer at a pressure of at least atmospheric pressure in atmosphere, wherein the annealing process is carried out using laser annealing, and wherein a laser used for the laser annealing has a visible light wavelength.

2. The manufacturing method according to claim 1, wherein the solvent comprises one or more solvents selected from a group consisting of water, alcohol, ether, ketone, glycol, glycerol, and terfenol.

3. The manufacturing method according to claim 1, wherein the coating layer has a thickness of 0.2 micrometer to 2.0 micrometer.

4. The manufacturing method according to claim 1, wherein the substrate is a plastic substrate or a glass substrate.

5. The manufacturing method according to claim 1, wherein a laser used for the laser annealing is an Nd-Yag laser, a disc laser, or a fiber laser.

6. The manufacturing method according to claim 1, wherein the laser annealing is carried out for 0.1 seconds to 5 minutes.

7. A transparent conductive film manufactured by a manufacturing method according to claim 1.

8. The transparent conductive film according to claim 7, wherein the transparent conductive film is made of indium tin oxide (ITO).

9. The transparent conductive film according to claim 7, wherein the transparent conductive film has a specific resistance of 0.001 Ωcm to 0.01 Ωcm.

10. The transparent conductive film according to claim 7, wherein the transparent conductive film has an average transmittance of 80% or more in a light spectrum of 400 to 800 nm.

11. A solar cell comprising a transparent conductive film according to claim 7.

12. A liquid crystal display device comprising a transparent conductive film according to claim 7.

Description

BEST MODE

(1) Now, the present invention will be described in more detail with reference to the following examples. These examples are provided only for illustration of the present invention and should not be construed as limiting the scope and spirit of the present invention.

Manufacture Example 1

(2) Composition of In-Core-Sn-Shell Nano Particle

(3) A water solution including 13.5 mmol of InCl.sub.3 and 50 mmol of sodium dodecylsulfate (SDS) was slowly dropwise added to a water solution including 150 mmol of NaBH.sub.4 for 1 hour and then the mixed water solutions were reacted with each other while being stirred for 24 hours to form a particle. Subsequently, a water solution including 1.5 mmol of SnCl.sub.2 was slowly dropwise added to the reacted water solutions and then the mixed water solutions were reacted with each other while being stirred for 1 hour and was refined using a centrifugal separation method to manufacture a core-shell structured In-core-Sn-shell nano particle.

Examples 1 to 3 and Comparative Examples 1 and 2

(4) Manufacture of Transparent Conductive Film Sample

(5) Samples were prepared on glass substrates according to deposition methods (IS means In-core-Sn-shell nano particle and ITO means indium oxide nano particle including tin), thickness conditions, and annealing treatment conditions as shown in Table 1.

(6) TABLE-US-00001 TABLE 1 Thick- Depo- ness sition (micro- Annealing condition method meter) Type Conditions Example 1 Glass substrate - 5.0/1.0 Laser UV laser, 10.6 μm, IS particle annealing 1 minute, 5 W, coating and air atmosphere Example 2 Glass substrate - 5.0/1.0 Laser UV laser, 10.6 μm, IS particle annealing 2 minutes, 6 W, coating and air atmosphere Example 3 Glass substrate - 5.0/1.0 Thermal 220° C., 1 hour, IS particle annealing and air atmosphere coating Compar- Glass substrate - 5.0/1.0 Thermal 220° C., 4 hours, ative ITO particle annealing and air atmosphere example 1 coating Compar- Glasssubstrate - 1.0 Sputtering None ative ITO thin film example 2 sputtering

Experimental Example 1

(7) After the samples were prepared as shown in Table 1, surface resistance, specific resistance, and (optical) transmittance of the samples were measured, which are shown in Table 2.

(8) TABLE-US-00002 TABLE 2 Surface resistance Specific resistance Transmittance (Ω/cm.sup.2) (Ωcm) (%) Example 1 975 0.0975 80 Example 2 512 0.0512 70 Example 3 2000 0.2 80 Comparative 3000 0.3 80 example 1 Comparative 10 0.001 85 example 2

(9) It can be seen from Table 2 that there is a possibility that Examples 1 and 2 exhibit surface resistance, specific resistance, and light transmittance equivalent to those of Comparative example 2 although Examples 1 and 2 formed the transparent conductive films using a non-vacuum coating process without using a conventional sputtering process which was used in Comparative example 2. In addition, it can be seen that Examples 1 and 2 exhibit much lower surface resistance and specific resistance than Comparative example 1, in which the conventional ITO nano particle was used and the thermal annealing coating process was carried out, and have a very small loss in optical transmittance. Furthermore, it can be seen that Example 3, in which thermal annealing was carried out instead of laser annealing, exhibits surface resistance and specific resistance higher than those acquired by the laser annealing but lower surface resistance and specific resistance than Comparative example 1, in which the conventional ITO nano particle was used.

(10) Moreover, comparison between Examples 1 and 2 shows that it is possible to exhibit more excellent surface resistance, specific resistance, and light transmittance through optimization of the laser annealing conditions. In addition, comparison among Examples 1, 2, and 3 shows that effects acquired when the laser annealing is carried out are more excellent than effects acquired when the thermal annealing is carried out.

(11) Although the exemplary embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

INDUSTRIAL APPLICABILITY

(12) As is apparent from the above description, in a case in which through an annealing process is carried out on a core-shell structured nano particle consisting of a core including indium or indium oxide and a shell including tin according to the present invention to manufacture a transparent conductive film, it is possible to manufacture the transparent conductive film using a non-vacuum manufacturing process, thereby reducing manufacturing process costs as compared with a conventional sputtering process and improving efficiency in use of materials.

(13) In addition, the core-shell structured nano particle, which is consisting of the core including indium or indium oxide and the shell including tin, exhibits high reactivity. Although the transparent conductive film is formed using the non-vacuum manufacturing process, therefore, the transparent conductive film may exhibit the same performance as a transparent conductive film formed using the conventional sputtering process.