KR100653959B1 - Preparation of patterned metal coated substrates using printing methods - Google Patents

Abstract

Provided are a method for forming a pattern of self-assembling monomolecular layer by using a printing technique, and a method for forming a pattern comprising dipping the pattern of self-assembling monomolecular layer into polymer solution capable of ion bonding, and forming a multilayered thin film by self-assembling mode. The method for forming a patterned substrate comprises the steps of (i) printing a compound of formula(1), X-(CH2)n-Y, on substrate by using inkjet, roll, or microcontact printing method, so as to form a pattern of monomolecular layer, and (ii) dipping the substrate into polymer solution reacting with the monomolecular layer to form a high molecular layer, and using the polymer layer as etching resist. In the formula(1), n is an integer of 2-20, X is thiol(-SH), imidazole or silyl group, Y is a functional group capable of ion bonding, and R is ethoxy or methoxy. The method for patterning a substrate comprises the steps of (a) forming a polymer film by the method as the above, (b) treating the film with heat and reacting the polymers with each other, so as to improve thermal and physical stability of the film.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a pattern on a metal substrate using a printing method,

1 is a schematic view of a multi-layer polymer membrane production method,

Fig. 2 is a schematic diagram for producing a pattern using a printing method and a multi-layered polymer film,

3 is a schematic view showing a continuous process using a roll-to-roll method,

4 is an optical microscope photograph of a copper pattern on a polyimide film patterned using a polymer multilayer film.

An object of the present invention is to provide a method of forming a monomolecular pattern on a metal substrate using a printing technique and a method of patterning a metal substrate using a polymer multilayer thin film formed by using a formed monomolecular film as a resist, And a method for applying the method.

As a method of forming a fine pattern of a printed circuit board, a film called a dry film resist is laminated on a copper substrate, and then a UV light source is irradiated through a mask to form a resist pattern. After the resist pattern is developed, And then dissolving copper in the portion to produce a circuit pattern. Such a photolithography method requires high-priced equipment such as a device for laminating a dry film to generate a pattern, a light source and a developing device, and has a problem of discarding by-products generated during development. Expensive equipments are necessary and there is a disadvantage that a pattern formation process at various stages is required.

In addition, a method of patterning a copper substrate by direct printing using an ink that can be used as a photoresist is also sometimes used, but in this case, since the kind of ink that can be used is extremely limited, it can be applied mainly by a method such as screen printing . In other words, inks suitable for inkjet or other printing methods have been developed very limited due to problems such as viscosity.

In order to solve these drawbacks, U.S. Patent No. 5900160 discloses a technique for forming a pattern of a self-assembled monolayer using a printing technique by a microcontact printing method and forming a fine pattern using a monolayer formed of a resist as a resistor Lt; / RTI >

In addition, WO 2004/013697 discloses a technique of patterning a gold surface by forming a self-assembled thin film on a gold surface by micro contact printing in a similar manner and etching it.

However, when a self-assembled monolayer is used as a resistor, a dense monolayer is formed when a gold surface is replaced with a molecule such as thiol, which can be used as a resist. However, an inferior structure is formed in the process of forming a monolayer with a metal such as copper . These structural defects of the monolayer do not adequately protect the etch solution, and copper-like surfaces do not produce precise patterns.

In addition, the gold surface and the like can be patterned by a thin film having a thickness of 1 μm or less and a thickness of several nanometers, but it is impossible to pattern a metal film having a thickness of several μm or more into a self-assembled thin film . It is impossible to obtain a fine fine pattern of a thick metal film such as a printed circuit board.

In order to overcome this disadvantage, instead of using a conventional monomolecular compound as an etching solution, nitrobenzenesulfonic acid is used as an oxidizing agent and a complex is formed with a polymer such as polyethyleneimine to prevent the oxidizing agent from penetrating into the dense monolayer Attempts have been made to increase the precision of patterns formed on copper substrates (M. Geissler et al., Microelectronic Engineering 67-68 (2003) 326).

However, this method is also not suitable for accurately patterning a thick copper layer such as a printed circuit board, which is currently widely used.

A method of forming a polymer multilayer thin film using ionic bonds or hydrogen bonds is well known (Science, 1977, 277, 1232 .; J. Am. Chem. Soc., 2002, 124, 2100.) As shown in Fig. 1, when anions or cations are present in the substrate, the polymer is immersed in a polymer solution having an opposite charge. When the polymer is immersed in the polymer solution, the polymer is strongly attracted to the surface by electrostatic attraction. When the polymer layer with opposite charge of one layer is raised, it is possible to stack a polymer layer having another opposite charge, and if it is repeated, it becomes a multi-layer polymer thin film. The use of such a method for modifying the surface and for use as a sensor is well known.

Accordingly, the present inventors have found that a self-assembled monolayer can be formed by a printing technique, and that when a multi-layered polymer film is stacked, a very fine pattern can be obtained effectively.

The present invention is characterized in that a compound having both a functional group capable of self-assembly with a substrate such as copper, gold or ITO and a functional group capable of ionic bonding is printed by a printing technique to form a self-assembled monolayer pattern, It has been found that not only the thickness of the pattern is increased by stacking the polymer layers one layer at a time, but also the defects existing in the monolayer are covered to increase the density, and thus it is possible to use the resist as a resist. The patterned multi- And a method of obtaining a fine pattern of a substrate such as copper, gold and ITO after the etching process has been known, and thus the present invention has been completed.

In order to accomplish the object of the present invention, the present invention provides a method of manufacturing a self-assembled monolayer pattern by a printing technique.

The present invention also relates to a self-assembling method of stacking up polymer layers by immersing a self-assembled monolayer pattern produced by a printing technique on a substrate of copper, gold, ITO or the like into a polymer solution capable of ionic bonding, The method comprising the steps of:

The general structure of the compounds used in the present invention to prepare self-assembled monolayer layers by printing techniques is represented by formula (1).

X- (CH ₂ ) _n -Y (Formula 1)

), 실릴 (

)기와 같이 금속 표면과 반응할 수 있는 작용기이며, Y는 이온 결합이 가능한 작용기이다. 여기서 R은 에톡시 혹은 메톡시 중 하나이다.Wherein n is an integer between 2 and 20, X is selected from the group consisting of thiol (-SH), imidazole (

), Silyl (

) Group, and Y is a functional group capable of ionic bonding. Wherein R is either ethoxy or methoxy.

Examples of the ionic bonding functional groups as possible in combination with cationic functional groups and the like, as _{-COOH, -SO 3 H, -PO 3} H 2, possible in combination with anionic functional groups such as -NH _2, -NR _3, -CONH ₂ Available.

As a printing technique for patterning the molecule of Formula (1) on a metal surface, microcontact printing, roll printing, inkjet printing, or the like can be used and fine patterns of a few microns or less can be formed.

The molecule of formula (1) reacts with gold or copper surface at the terminal thiol (-SH) group and forms a self-assembled monolayer, so that the ion-binding functional group at the other end is exposed on the surface. The substrate on which the functional groups are exposed is alternately immersed in a cationic polymer or an anionic polymer solution capable of ionic bonding to form a self-assembled multilayer thin film. In this case, when a monomolecular film is formed of a compound having -COOH, -SO ₃ H, or -PO ₃ H ₂ functional groups capable of binding with cations, the substrate is first immersed in the cationic polymer solution, and the functional groups -NH ₂ , When a monomolecular film is formed of a compound having NR ₃ , -CONH ₂ functional groups, the substrate is first immersed in an anionic polymer solution.

Examples of the cationic polymer include polyethyleneimine, polyvinylpyridine, polyacrylamide, and polyallylamine hydrochloride. Examples of the anionic polymer include polystyrenesulfonic acid, polystyrenesulfonate, polyvinylsulfonic acid, polyvinylsulfonate, poly Acrylic acid and the like can be used.

When the terminal ionic bond is composed of a carboxyl group (-COOH) and an amine group (-NH ₂ , -CONH ₂ ), the temperature can be elevated to an amide group or an imide group, The density, stability and mechanical strength are greatly increased. Particularly in the case of polyacrylamide, a very excellent imide thin film is produced. Therefore, it is suitable as a resist used in a process such as etching at a high temperature or for a long time.

The pattern formed by the self-assembled multilayer thin film on the copper substrate is immersed in the etching solution and is etched to obtain a fine pattern on the copper substrate. The etching solution may be usually an etching solution used in the industry. The composition of the etching solution is CuCl ₂ -NaClO ₃ , K ₂ S ₂ O ₃ -K ₃ F ₂ (CN) ₆ -K ₄ F ₂ (CN) ₆ , sodium nitrobenzenesulfonate-polyethyleneimine polyethyleneimine) are mainly used in combination.

The pattern formation using such a self-assembled thin film is advantageous over other conventional inks because a monomolecular compound is dissolved in an appropriate solvent and thus can be easily applied to inkjet printing and microcontact printing with a suitable viscosity solution. As the solvent that can be mainly used, a solution having a viscosity of about 3 to 7 cp is suitable as an alcohol solvent such as ethanol and an organic solvent mixture such as propylene glycol methyl ether acetate.

Since the resist coated with the multilayer thin film is very stable in the heat and solution process, it is subjected to the immersion process several times. Therefore, when the thickness of the metal to be etched is 10 μm or less, if the concentration of the first immersed polymer solution is increased, Lt; / RTI > on the self-assembly pattern. Therefore, a resist film that can withstand the etching conditions can be obtained even after immersing in the polymer solution only once.

Such a patterning method is not limited to a copper substrate but can be applied to a metal substrate on which a thiol and a monomolecular film can be formed, such as gold. In particular, when X is a silyl group in the formula 1, patterns such as ITO and SiO ₂ are possible.

In addition, since the pattern manufacturing method according to the present invention is suitable for a roll-to-roll method as shown in FIG. 3, it has an advantage that patterning can be performed in a continuous process, (A) withdrawing a substrate from a roll; (b) forming a monolayer pattern on the substrate by printing in a printing machine; (c) forming a polymer layer that is immersed in a polymer solution tank interacting with the monolayer of the printed substrate; (d) etching the substrate in an etching solution bath to form a pattern; (e) removing the etching resist by a resist washing bath; And drying in a drying furnace.

The method may further include a step of washing in a washing tank after the step (a), and the washing step may further include a step of drying in a drying furnace.

The method may further include a step (c-1) of immersing the polymer layer in another polymer solution tank interacting with the polymer layer after the step (c) to form a polymer layer. In the step (c) 1) -step polymer solution tank to repeatedly immerse the polymer solution in step (c) and the polymer solution in step (c-1) alternately to form a plurality of self-assembled polymer layers.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to the examples.

[Example 1]

25mM mercaptoundecanoic acid (MUA) was dissolved in ethanol and propylene glycol methyl ether acetate to transfer the pattern onto a polyimide flexible copper substrate by microcontact printing. At this time, the stamp was prepared by a known method using PDMS. The pattern transfer was carried out by contacting a stamp with a 25 mM mercapto-decanoic acid (MUA) ethanol solution immersed on a copper substrate for 30 seconds. Wash the patterned copper substrate with ethanol solution.

The patterned copper substrate is immersed in a 1% by weight aqueous solution of polyacrylamide for 10 minutes and washed well with water. The substrate is immersed in a 1 wt% aqueous solution of polyacrylic acid for 10 minutes and then washed with water to form a polymer self-assembled thin film.

The method of alternately immersing the polyacrylamide aqueous solution and the polyacrylic acid aqueous solution in the same manner as described above is repeated four more times to form five self-assembled polymer thin films.

This substrate is etched in a copper etching solution for 10 minutes to obtain a fine pattern. At this time, an aqueous solution in which 0.1 MK ₂ S ₂ O ₃ , 0.01 MK ₃ F ₂ (CN) ₆ and 0.001 MK ₄ F ₂ (CN) ₆ were dissolved was used as the copper etching solution. FIG. 4 is an optical microscope picture of the copper pattern thus formed.

[Example 2]

As an anionic polymer that forms a self-assembled multilayer thin film by using 10-aminodecanethiol as a compound forming a self-assembled monolayer and transferring a pattern by a micro contact printing method, 1 wt% of polystyrene sulfonate and 1 wt% of a cationic polymer A self-assembled multilayer thin film of 5 layers was formed in the same manner as in Example 1 using polyallylamine hydrochloride in weight%.

This substrate was etched using the etching solution of Example 1 to obtain a fine pattern of several micrometers.

[Example 3]

25 mM mercapto decanoic acid (MUA) is dissolved in ethanol and propylene glycol methionine acetate to transfer the pattern onto the polyimide flexible copper substrate by the ink jet printing method. The ink used for the pattern transfer was prepared by dissolving 25 mM of mercapto decanoic acid (MUA) in an ethanol solution.

A self-assembled multilayer thin film was formed by the same method as in Example 1, and then patterned in an etching solution to obtain a fine pattern of several micrometers.

[Example 4]

A monomolecular film was formed using the same method as in Example 3, and then immersed in a 5 wt% aqueous solution of polyacrylamide for 5 minutes to 10 minutes to form a second polymer layer, followed by washing with pure water. Thereafter, an etching process was performed to obtain a pattern of several mu m. When a high concentration polymer solution is used, it can be dipped once to form a thick film, which is advantageous in the process and there is no significant difference in pattern formation.

[Example 5]

The resultant was immersed in an aqueous solution of polyacrylamide, taken out and heat treated at 180 ° C for 30 minutes to be imidized and subjected to an etching process to obtain an excellent pattern.

[Example 6]

The same method as in Example 1 or a substrate was carried out using a silicon wafer having gold deposited thereon with copper to obtain a gold pattern having a resolution of 5 탆.

[Example 7]

Etching was performed at a temperature of 60 to 80 占 폚 in an aqueous solution in which 0.05 M of sodium nitrobenzenesulfonate and 3.5 M of polyethyleneimine dissolved in the same manner as in Example 5 to obtain an excellent pattern.

[Example 8]

25 mM of 3-aminopropyl triethoxy silane was dissolved in ethanol, and the resultant was put on a patterned roll, and printed on an ITO substrate (ITO thickness: 800 nm). After drying at about 45 ° C, it was immersed in a solution of polyacrylic acid dissolved, then taken out and washed with pure water. This was immersed in a solution of 1 M nitric acid and hydrochloric acid dissolved for 1 minute. A pattern having a resolution of 10 mu m grade was obtained.

A method of manufacturing a patterned substrate according to the present invention is a method of manufacturing a patterned substrate by printing a compound having both a functional group capable of self-assembly with a substrate such as copper, gold, or ITO and a functional group capable of ionic bonding, It is possible not only to increase the thickness of the pattern by stacking the polymer layers to form a multilayer thin film but also to cover the defects existing in the monolayer and increase the density to use the resist as a resist. There is an advantage that fine patterns with high resolution of substrates such as copper, gold and ITO can be obtained after the etching process.

Further, the resist coated with the multilayer thin film according to the present invention is advantageous in that it is excellent in heat resistance and resistance to etching and thus precise patterning of a thick copper layer such as a printed circuit board.

Claims (12)

(a) printing a compound represented by the following formula (1) on a substrate by ink jet, roll or microcontact printing to form a monolayer pattern; (b) immersing in a polymer solution interacting with the monomolecular layer to form a polymer layer, and using the polymer layer as an etching resist. X- (CH ₂ ) _n -Y (Formula 1) Wherein n is an integer of 2 to 20, and X is thiol (-SH), imidazole (

) Or silyl (

) Group, Y is a functional group capable of ionic bonding, and R is one of ethoxy and methoxy. The method according to claim 1, And (c) after the step (b), dipping the polymer layer in another polymer solution interacting with the polymer layer to form a polymer layer. 3. The method of claim 2, Wherein the step (b) and the step (c) are repeated two or more times to have a multi-layered polymer layer structure in which a mutually interacting polymer layer is repeatedly formed to function as an etching resist. 3. The method of claim 2, The polymer layer is a _{-COOH, -SO 3 H, -PO 3} H 2 functional groups having the polymer solution and -NH _2, -NR _3, -CONH multi-layer polymer is immersed by laminating alternately a polymer solution having a _second functional layer Wherein the pattern substrate has a surface roughness of at least 10 占 퐉. 5. The method of claim 4, Wherein the polymer used in the polymer solution is selected from the group consisting of a polymer selected from polyethyleneimine, polyvinylpyridine, polyacrylamide and polyallylamine hydrochloride and a polymer selected from polystyrene sulfonic acid, polystyrenesulfonate, polyvinylsulfonic acid, polyvinylsulfonate and polyacrylic acid Wherein one of the polymer solutions is alternately laminated. The method according to claim 1, Wherein the substrate is any one selected from gold, copper, and ITO. A process for producing a patterned substrate, comprising the steps of: preparing a polymer film by the method according to any one of claims 2 to 6, followed by heat treatment to effect mutual reaction between polymers to improve thermal stability and mechanical stability. (a) withdrawing a substrate from a roll; (b) forming a monolayer pattern on the substrate by printing in a printing machine; (c) forming a polymer layer that is immersed in a polymer solution tank interacting with the monolayer of the printed substrate; (d) etching the substrate in an etching solution bath to form a pattern; (e) removing the etching resist by a resist washing bath; And a drying step in a drying furnace. The apparatus for continuously manufacturing a pattern substrate for transferring a substrate in a roll-to-roll manner. 9. The method of claim 8, The method of manufacturing a pattern substrate according to claim 1, further comprising the step of cleaning the substrate in the cleaning tank after the step (a). 10. The method of claim 9, And drying the substrate in the drying furnace after the cleaning step. 9. The method of claim 8, And (c-1) a step (c-1) of immersing the polymer layer in another polymer solution tank interacting with the polymer layer after the step (c) to form a polymer layer. Manufacturing apparatus. 12. The method of claim 11, Wherein the plurality of polymer layers are repeatedly transferred to the polymer melt baths of (c) and (c-1), thereby transferring the substrate by the roll-to-roll system.

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