TW201409490A - Manufacturing method of transparent electric conduction film - Google Patents

Abstract

A manufacturing method of transparent electric conduction film includes cladding a plating solution on a base and to toast the base, doing at least one of the cladding and the toasting until forming at least one film on a surface of the base, sintering the base until the film above-mentioned to be solidify, and etching the base by a acid-etched solution until a surface of the film above-mentioned to be roughed and form a rough interface, cleaning the acid-etched solution remained on the base and repeat the cladding, the toasting and the sintering until a plurality of film to be laminated, and the plurality of film is to form the transparent electric conduction film.

Description

Transparent conductive film manufacturing method

The present invention relates to a method for fabricating a transparent conductive film, and more particularly to a method for fabricating a transparent conductive film capable of improving the interface fit between layers of a plurality of layers.

Nowadays, transparent conductive films have been widely used in the optoelectronic industry, and the characteristics of good conductivity and light transmission of transparent conductive films have obviously contributed to the development of various optoelectronic products such as liquid crystal displays, plasma displays, and touch panels.

Therefore, in order to increase the conductivity and light transmission efficiency of the transparent conductive film, the manufacturer generally repeats the plating solution by a wet chemical method (such as a lift coating method, a spin coating method, etc.). A conventional transparent conductive film is formed by a coating method such as baking and sintering, and the resistivity of the conventional transparent conductive film is reduced by stacking the multiple film layers to improve the conductivity.

However, when the transparent conductive film is formed by stacking a plurality of film layers, the film thickness caused by the stacking of the plurality of film layers is increased, and the light transmittance of the transparent conductive film is relatively poor. In addition, due to the coating process of the multi-film layer stack, it is necessary to repeatedly operate the plating liquid coating, drying and sintering steps, so that the interface between the film layer and the film layer is easily contaminated by the repeated coating process, and The repetitive high-temperature sintering produces a distinct interface, and as the number of layers increases, the interface between them is more pronounced. In this way, due to the interface between the film layer and the film layer, the degree of interface between the film layer and the film layer is obviously poor, which not only causes peeling of the film layers, but also prevents the resistance of the transparent conductive film. The rate and light transmittance are remarkably improved, so the adhesion, conductivity, and light transmittance of the conventional transparent conductive film are still further improved. space.

In view of this, it is indeed necessary to develop a novel transparent conductive film fabrication method to improve the interface fit between the multilayer film layers, thereby solving various problems as described above.

SUMMARY OF THE INVENTION The main object of the present invention is to improve the above disadvantages and to provide a method for producing a transparent conductive film which can improve the interface fit between the multilayer film layers to relatively reduce the resistivity and enhance the conductivity and light transmittance.

In order to achieve the above object, the method for fabricating a transparent conductive film of the present invention comprises: first coating a substrate with a plating solution, and baking, the plating solution and the baking system are operated at least once for the substrate Forming at least one film on the surface; sintering the substrate until the at least one film layer on the surface of the substrate is cured by heat; etching the substrate with an acid etching solution until the surface of the at least one film layer of the substrate is subjected to the acid The etching solution is eroded and roughened to form a roughening interface; the etching solution remaining on the substrate is washed away by a solvent, and the plating solution is repeatedly coated, baked and sintered to complete the multi-layer on the substrate. In the stacking, the multi-film layer constitutes a transparent conductive film.

In order to achieve the above object, another transparent conductive film manufacturing method of the present invention comprises: first coating a substrate with a plating solution, and baking, the plating solution and the baking system operation at least once, so as to Forming at least one film layer on a surface of the substrate; sintering the substrate until the at least one film layer on the surface of the substrate is cured by heat; etching the substrate by using an acid etching solution until a surface of the at least one film layer of the substrate is subjected to The acid etching solution is eroded and roughened to form a roughened interface; the solvent is used to wash away the acid residue dissolved on the substrate The liquid is repeatedly subjected to coating, baking, sintering and etching to form a multi-film layer on the substrate, and the multi-film layer constitutes a transparent conductive film.

Wherein, the acid etching system controls the pulling speed to be 100-300 mm/min, and the substrate is continuously immersed in the etching solution for 1 to 30 seconds.

The acid etching solution may be selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid and acetic acid, and the acid concentration of the acid etching solution is adjusted to be 0.1 to 10 wt%.

Wherein, the plating solution is controlled to have a pulling speed of 100 to 300 mm/min, so that the plating solution is uniformly coated on the surface of the substrate.

The baking method is a stage drying, and the baking temperature is 70-150 ° C and 200-350 ° C.

The temperature of the sintering was controlled to 500 ° C, and the substrate was continuously sintered for 2 hours.

The above and other objects, features, and advantages of the present invention will become more apparent from the description of the preferred embodiments of the invention. It can be used to prepare various transparent conductive films formed by film layer stacking, such as metal films such as gold, silver, aluminum, etc.; or metal oxide semiconductor films such as zinc oxide, tin oxide, indium tin oxide, etc. can be passed through the present invention. The method is described.

Hereinafter, a preferred embodiment of the present invention is disclosed. The method for fabricating a transparent conductive film of the present invention can be selected by various wet coating methods such as a lift coating method and a spin coating method, and the transparent conductive film to be formed is different. Type, The characteristics enable the person skilled in the art to select different plating solutions more selectively, and the composition of the plating solution is not the main technical feature of the present invention, and thus will not be further described herein without limitation.

The transparent conductive film manufacturing method of the present invention performs the following steps: first coating a substrate with a plating solution, and baking, the plating solution and the baking system are operated at least once to form at least one film on one surface of the substrate. Floor. And continuing to sinter the substrate until the film layer on the surface of the substrate is cured by heat; and etching the substrate by using an acid etching solution until one surface of at least one film layer of the substrate is eroded by the etching solution Generate a rough interface. Then, a solvent is used to wash away the etching solution remaining on the substrate, and the plating solution is repeatedly coated and baked at least once, and finally the substrate is sintered again to complete stacking of the multi-layer on the substrate. Further, a transparent conductive film is formed from the multi-film layer.

In detail, the plating solution is exemplified by the pull-up coating method, and the substrate is selected to be immersed in the plating solution, and the plating solution is evenly spread on the surface of the substrate, and then the substrate is pulled up to make excess plating solution. After being dripped by the environmental gravity factor and continuously dried, the plating solution can be closely attached to the surface of the substrate to form a film layer. At this point, the person skilled in the art can choose to repeat the step according to the requirement, after the substrate is stacked with the required number of basic film layers, and then the substrate formed with at least one film layer is successively sintered until the film layer on the surface of the substrate is heated. Cured by action.

For example, the plating solution can selectively control the pulling speed to 100-300 mm/min, so that the plating solution is evenly coated on the surface of the substrate, and is passed through a stage of 70-150 ° C and 200-350 ° C. Dry the formed film layer, and repeat the number of basic film layers up to 2, 3, 4, etc., as appropriate, and then heat at 500 °C. The substrate is thermally sintered for about 2 hours, causing the multilayer film layer on the substrate to be cured by heat. In this way, not only the cost and time required for each high temperature thermal sintering of each film layer on the substrate can be omitted, but also the subsequent acid etching can be carried out in consideration of economic considerations, thereby improving the convenience of production.

The acid etching system soaks the substrate in the etching solution, so that when the cured and cured film layer touches the etching solution, the etching solution is likely to be highly aggressive due to the etching solution. The contact surface of the film layer and the etching solution is eroded by oxidation, so that the surface of the film layer is covered with erosion marks and evolves into a rough surface of unevenness, which is called a roughening interface. At the same time, the sintered dirt attached to the film layer can be washed away in the acid etching process to improve the fit of the film layers to each other. Wherein, the acid etching solution may be selected from various acidic liquids such as hydrochloric acid, nitric acid, sulfuric acid, acetic acid, or the like, or may be selected from any two, three, ... acidic liquids mixed, and the acid etching solution is adjusted. The acid concentration is 0.1 to 10 wt%, so that the acid etching solution has a better acid etching effect.

For example, the acid etching system also controls the pulling speed to be 100-300 mm/min, so that the substrate is immersed in the etching solution for about 1 to 30 seconds, preferably for 10 to 20 seconds. The effect is that until the film layer of the uppermost layer of the substrate is gradually covered with rough and irregular rough marks due to acid etching, a relatively uniform roughening interface can be formed on the surface.

In this way, the solvent etching solution remaining on the substrate can be selected by using a solvent to re-operate the plating solution and baking process as needed until the desired film layer is formed on the substrate. In total, a transparent conductive film can be obtained. In detail, after washing the acid etching solution remaining on the surface of the substrate with water as a solvent, it is necessary to repeatedly operate the plating solution and bake. The baking process is performed at least once, so that the plating solution can closely conform to the roughening interface, and the substrate is sintered again to form the transparent conductive film by stacking of the multi-film layers. That is, the person skilled in the art can select, at least once, the process of coating and baking the plating solution at least once, so as to cover at least one film layer in the roughening boundary, and complete the total number of layers of the desired stack on the substrate. After that, the production of the transparent conductive film can be completed by sintering to cure.

Moreover, in the process of repeatedly performing the film layer stacking as described above, it is still possible to selectively use the acid etching solution to roughen the surface of the film layer as needed to form a roughened interface on the film layer of more than one layer; in other words, the present invention also The film may be sequentially formed by coating, baking, sintering and etching to form a multi-layer layer, so as to form a rough interface between any two adjacent layers, and to be coated and baked in the last plating solution. After the sintering, the transparent conductive film is completed to enhance the degree of adhesion between the respective film layers by the roughening interface. In this way, when the film layer is subsequently stacked, the plating solution can be filled to fill the roughening interface of different film layers to increase the contact area between the plating solution and the surface of the film layer, thereby causing any two adjacent film layers. The interface fit effect is maximized.

The above is under the same technical concept, and the order of operation is changed to meet the needs of the work, so it can be understood by those having ordinary knowledge in the field, and is implemented on the basis of the foregoing.

Hereinafter, taking a zinc oxide film as an example, the zinc oxide film is composed of six film layers, and the surface of the film layer of the third layer is subjected to acid etching for different time, so that the film layers of the third and fourth layers are present. Thicken the interface. In this regard, the difference in sheet resistance, transmittance, and film thickness of the zinc oxide film is compared, as shown in Tables 1, 2, and 3.

Above, as shown in Table 1, when the zinc oxide film is continuously acid-etched by the acid etching solution for about 10 to 20 seconds, the zinc oxide film obviously has a lower sheet resistance value, and the effect of effectively reducing the resistivity is achieved; When the etching time is gradually extended to 30 seconds, and even more than 30 seconds, the sheet resistance of the zinc oxide film is significantly increased and the standard deviation is relatively increased. As shown in Table 2, zinc oxide film The transmittance will be significantly improved by the erosion of the acid etching solution, but the difference in light transmittance will not be caused by the length of the etching time. As shown in Table 3, the thickness of the zinc oxide film is also apparently under the acid etching for 10 to 30 seconds, and the surface is gradually thinned due to acid etching.

When the zinc oxide film was observed by Scanning electron microscopy (SEM), as shown in Fig. 1A to 1D [1A: etching time 0 seconds; 1B: etching time 10 seconds; 1C: etching time 20 seconds) ; 1D: acid etching time 30 seconds], as the etching time increases, the smooth surface of the film originally appeared in Figure 1A is obviously after the acid etching of 10~30 seconds, immediately as the 1B~1D The transition shown is a rough roughened surface. And with the 2A~2D diagram [2A: acid etching time 0 seconds, thickness 1700.6 nm; 2B: acid etching time 10 seconds, thickness 1630 nm; 2C: acid etching time 20 seconds, thickness 1541.6 nm; 2D: acid The etch time is 30 seconds and the thickness is 1499.3 nm. When the etching time is increased to 10~30 seconds, the existence of the roughening interface makes the adjacent two layers have a more suitable stack, so that The relative lamination traces as shown in Fig. 2A are not seen again in the 1B~1D diagram.

In summary, the main feature of the method for fabricating the transparent conductive film of the present invention is that the high etching property of the acid etching solution enables the contact surface of the film layer and the etching solution to be oxidized and eroded. The surface of the film is covered with erosion marks, and further evolves into a rough surface with irregularities. In this way, the coarsened interface through the roughening can enhance the contact area when the film is in contact with the film, so as to force a better interface fit between the multiple layers, thereby lowering the resistivity and improving its conductivity and light transmittance. efficacy.

Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the invention, and those skilled in the art can The scope of the present invention is to be construed as being limited by the scope of the appended claims.

1A~1D: Scanning electron micrograph of the surface of the zinc oxide film.

2A~2D: Scanning electron micrograph of the cross section of the zinc oxide film.

Claims (7)

A method for fabricating a transparent conductive film, comprising: first coating a substrate with a plating solution, and baking, the plating coating and baking operation at least once to form at least one film layer on a surface of the substrate; Sintering the substrate until the at least one film layer on the surface of the substrate is cured by heat; etching the substrate with an acid etching solution until a surface of the at least one film layer of the substrate is etched by the etching solution to be coarsened a roughening interface; the acid etching solution remaining on the substrate is washed away by a solvent, and the plating solution is repeatedly coated, baked and sintered to complete stacking of the multi-film layer on the substrate, the multi-film layer That is, a transparent conductive film is formed. A method for fabricating a transparent conductive film, comprising: first coating a substrate with a plating solution, and baking, the plating coating and baking operation at least once to form at least one film layer on a surface of the substrate; Sintering the substrate until the at least one film layer on the surface of the substrate is cured by heat; etching the substrate with an acid etching solution until a surface of the at least one film layer of the substrate is etched by the etching solution to be coarsened a roughening interface; the acid etching solution remaining on the substrate is washed away by a solvent, and the plating solution is repeatedly coated, baked, sintered, and etched to complete stacking of the multi-film layer on the substrate. The multi-film layer constitutes a transparent conductive film. The transparent conductive film manufacturer as described in claim 1 or 2 The method wherein the acid etching system controls the pulling speed to be 100 to 300 mm/min, and the substrate is continuously immersed in the etching solution for 1 to 30 seconds. The method for producing a transparent conductive film according to claim 1 or 2, wherein the acid etching solution is selected from the group consisting of hydrochloric acid, nitric acid, sulfuric acid and acetic acid, and the acid concentration of the etching solution is adjusted. It is 0.1~10 wt%. The method for fabricating a transparent conductive film according to claim 1 or 2, wherein the plating solution is controlled to have a pulling speed of 100 to 300 mm/min, so that the plating solution is uniformly coated on the surface of the substrate. . The method for producing a transparent conductive film according to claim 1 or 2, wherein the baking is a stage drying, and the baking temperature is 70 to 150 ° C and 200 to 350 ° C. The method for producing a transparent conductive film according to claim 1 or 2, wherein the sintering is performed at a temperature of 500 ° C, and the substrate is continuously sintered for 2 hours.