Photosensitive dry film, composition solution generating the same, and electroless plating method of metal layer

Abstract

To provide a photosensitive dry film, to provide a composition solution which generates the same, and to provide an electroless plating method of a kind of metal layer.SOLUTION: A photosensitive dry film includes a composition for catalyst formation and a photocatalyst 102. The composition for catalyst formation includes a metal complex and a water-soluble polymer 106. The photocatalyst is dispersed in the composition for catalyst formation, and the photocatalyst is deposition of a photocatalyst precursor. In the photosensitive dry film, a composition solution is dried, exposed and developed and the photocatalyst is deposited first, and then, the photocatalyst is induced to generate an electron-hole, and on the surface of the photocatalyst, metal particles 104 are reduced and generated. With the metal particles being a catalyst, electroless plating is performed and a metal layer can be formed.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to electroless plating technology, and in particular, to a photosensitive dry film, a composition solution for producing the same, and a method for electroless plating of a metal layer.

Background Art

[0002] In electroless plating, metallic palladium is used as a seed to induce the reaction. However, metallic palladium is expensive, and replacing it with other materials has become a trend in technological development. In particular, in electroless copper plating using formaldehyde as a reducing agent, based on the comparison of oxidation potentials, the catalytic activity order of each metal is presumed to be Cu>Au>Ag>Pt>Pd>Ni>Co.

[0003] Therefore, it is considered that using copper as a catalyst for copper plating with formaldehyde has the advantage of obtaining relatively high activity. However, the reason why it is not common to use copper as a catalyst is that it is difficult and the advantages are not obvious. For example, when using copper metal particles generated by a preliminary reaction as a catalyst, there are many disadvantages such as high cost, surface oxidation, easy aggregation of particles, and the need for complicated operations such as redispersion for use, making it not easy to store. When generating copper metal particles in-situ using the ion method, it is not as simple as noble metals such as Pd and Ag because it is easily oxidized and loses its activity, and it cannot be achieved by the conventional wet sensitization / replacement method.

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present invention provides a photosensitive dry film having a composition capable of inducing in-situ reduction using light energy to generate catalytic metal particles.

[0005] The present invention further provides a composition solution for producing a photosensitive dry film that can be used to form the above dry film.

[0006] The present invention further provides an electroless plating method of a metal layer that can form a catalyst pattern by light, has metal particles formed on the surface of a photocatalyst as a patterned catalyst, and continuously induces an electroless plating metal reaction to generate a conductor line.

Means for Solving the Problems

[0007] The photosensitive dry film of the present invention contains a catalyst-forming composition and a photocatalyst. The catalyst-forming composition contains a metal complex and a water-soluble polymer. The photocatalyst is dispersed in the catalyst-forming composition, and the photocatalyst is a precipitate after drying a photocatalyst precursor.

[0008] The composition solution for producing the photosensitive dry film of the present invention contains a metal salt compound, an amine compound as a complexing agent, a photocatalyst precursor, a water-soluble polymer, and a solvent.

[0009] The electroless plating method of the metal layer of the present invention includes preparing a composition solution for producing the photosensitive dry film, preparing a substrate, forming an adhesive layer on the substrate, applying the composition solution for producing the photosensitive dry film on the surface of the substrate, and forming a photosensitive dry film after drying. The photosensitive dry film contains a catalyst-forming composition and a photocatalyst dispersed in the catalyst-forming composition. The catalyst-forming composition contains a metal complex and the water-soluble polymer. The photocatalyst is a precipitate after drying a photocatalyst precursor. Then, a local region or the entire region of the photosensitive dry film is exposed to induce the photocatalyst to generate electron-hole pairs, reduce the metal complex on the surface of the photocatalyst to generate metal particles, and further perform electroless plating using the metal particles as a catalyst to form a metal layer.

Effects of the Invention

[0010] Based on the above, the present invention adopts a photo - electrical reduction method, uses a photocatalyst as a carrier, and provides an electron - hole pair, so that light energy can be used to induce the generation of electrons required for the reduction reaction. Furthermore, the present invention uses a water - soluble polymer as a hole scavenger to achieve energy transfer and balance, while serving as anti - oxidative protection for newly generated metal particles to avoid excessive oxidation. After light irradiation, metal particles (catalysts) precipitate and embed on the surface of the photocatalyst and are fixed on the substrate. However, the non - irradiated sites still exhibit an ionic state and can be removed with a detergent. Therefore, a pattern of catalyst seeds can be formed using light, and the electroless plating metal reaction can be continuously induced to form conductor lines.

[0011] To make the above - mentioned features of the present invention clearer and easier to understand, embodiments will be given below and described in detail with reference to the accompanying drawings.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

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Figure 4

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Figure 7

Figure 8

Mode for Carrying Out the Invention

[0013] The photosensitive dry film according to an embodiment of the present invention contains a catalyst-forming composition and a photocatalyst.

[0014] The above photocatalyst is a composition solution for producing a photosensitive dry film, is the first solid matter deposited in the drying process, and is dispersed in the catalyst-forming composition.

[0015] In the present embodiment, the catalyst-forming composition contains a metal complex and a water-soluble polymer. Here, the metal complex is the remaining product after drying the composition solution for producing the photosensitive dry film.

[0016] The above photosensitive dry film is obtained by coating and drying a composition solution for producing the photosensitive dry film. The composition solution contains a mixture of a metal salt compound, an amine compound as a complexing agent, a water-soluble polymer, a photocatalyst precursor, and a solvent. After coating and drying the above composition solution on a substrate, photocatalyst particles are deposited on the substrate, leaving the catalyst-forming composition. The formed photocatalyst particles are dispersed in the catalyst-forming composition. The metal complex in the above catalyst-forming composition is a reactant formed by a complex reaction between the amine compound and the metal salt compound in the above composition solution.

[0017] The above metal salt compound may be one or more mixtures selected from the group consisting of sulfates, nitrates, acetates, formates, and chloride salts of nickel (Ni), copper (Cu), palladium (Pd), and silver (Ag). For example, the metal salt compound may be copper acetate, copper formate, palladium acetate, etc. The above amine compound may be at least one selected from the group consisting of ethanolamine (MEA), triethanolamine (TEA), diethanolamine (DEA), ethylenediamine (EDA), propylenediamine (1,2-diaminopropane), dimethylamine, 2-aminoisobutanol (2-amino-2-methyl-1-propanol, AMP), isopropanolamine (1-amino-2-propanol), and 1-octylamine. The amine compound as a complexing agent can form a metal complex with the metal salt compound.

[0018] In one embodiment, the molar concentration ratio of the total amine groups of the amine compound to the metal ions of the metal salt compound is 1.5 to 10, for example, 1.5 to 4, or 2 to 4. However, the present invention is not limited thereto, and depending on the metal salt compound or the amine compound, the molar ratio may be lower or higher, and the formed complex can be reduced by a photoelectric effect, and at the same time, it is determined by whether the stability during storage at room temperature can be achieved. The formed complex is supplied for the reduction precipitation of metal particles (catalysts) in the subsequent dry film state. Examples of the water-soluble polymer include, but are not limited to, polyvinyl alcohol (Poly Vinyl Alcohol, PVA), polyvinyl pyrrolidone (Poly Vinyl Pyrrolidone, PVP), polyethylene glycol (Poly Ethylene Glycol, PEG), polyethyleneimine (Poly Ethylene Imine, PEI), methyl cellulose (Methyl Cellulose), gelatin (Gelatin), starch (Starch), chitosan (Chitosan), or a combination thereof.

[0019] In this embodiment, the photocatalyst is a precipitate formed by the photocatalyst precursor in the drying process. Examples of the aforementioned photocatalyst include, but are not limited to, titanium dioxide (TiO2), zinc oxide (ZnO), or a combination thereof. In one embodiment, based on the total weight (weight percentage) of the photosensitive dry film, the content of the photocatalyst is, for example, 1% to 70%.

[0020] In this embodiment, examples of the photocatalyst precursor include, but are not limited to, titanium isopropoxide, titanium butoxide, zinc methoxide, zinc n-propoxide, or a combination thereof. In one embodiment, based on the total weight of the composition solution, the content of the photocatalyst precursor is 0.1% to 3.0%. As the solvent of the composition solution, known solvents such as methanol, ethanol, and water can be used, but the present invention is not limited thereto.

[0021] Before the photosensitive dry film is irradiated with light (such as UV light), it exists in a state of being dispersed in the composition in the form of photocatalyst particles. However, after light irradiation, it is as shown in FIG. 1. The left side of FIG. 1 is the structure 100 after illumination, and the right side of FIG. 1 is a partial enlarged schematic view of the left figure.

[0022] Referring to FIG. 1, after light irradiation, the photocatalyst 102 generates an electron-hole pair. Here, the electron e - is provided to the complex ion to reduce the metal ion to zero-valent metal particles 104 on the surface of the photocatalyst 102 or dope it into the photocatalyst 102 (not shown). The hole h generated in this process + is absorbed by the water-soluble polymer 106 covering the surroundings. In the above absorption process, on the one hand, the water-soluble polymer as a sacrificial acceptor is oxidized by the hole and decomposed into CO, CO2, H2O, etc., while on the other hand, it can protect the newly generated metal particles 104 in the nucleus. That is, in this embodiment, the photocatalyst 102 is used as a carrier, and further, the water-soluble polymer 106 is used for the anti-oxidative protection of the newly generated metal particles 104 and at the same time as a hole-scavenger to form a complete energy transfer. In this way, the electron e - and the hole h +All of them are absorbed by the receptor, and by reducing the possibility of ineffective self-recombination, favorable conditions for the precipitation of metal particles 104 by light reception are constituted, and the purpose of in-situ reduction and generation can be achieved.

[0023] Therefore, in the process of forming the catalyst (metal particles 104) of the present embodiment, the reduction of metal ions can be induced only by light irradiation, and there is no need to use a chemical reducing agent.

[0024] FIG. 2 is a schematic cross-sectional view showing an electroless plating flow of a metal layer according to another embodiment of the present invention.

[0025] Referring to FIG. 2, in the electroless plating method of the metal layer of the present embodiment, first, a composition solution for generating a photosensitive dry film is prepared. The composition solution for generating the photosensitive dry film contains a metal salt compound, an amine compound, a photocatalyst precursor, a water-soluble polymer, and a solvent as described above. The metal salt compound may be one or more mixtures selected from the group consisting of sulfates, nitrates, acetates, formates, and chloride salts of nickel, copper, palladium, and silver. The amine compound may be at least one selected from the group consisting of ethanolamine, triethanolamine, ethylenediamine, propylenediamine, dimethylamine, 2-aminoisobutanol, isopropanolamine, and 1-octylamine. Examples of the photocatalyst precursor include, but are not limited to, titanium isopropoxide, titanium butoxide, zinc methoxide, zinc propoxide, or a combination thereof. Examples of the water-soluble polymer include, but are not limited to, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, polyethyleneimine, methylcellulose, gelatin, starch, chitosan, or a combination thereof. In one embodiment, the molar concentration of the metal salt compound is 0.01M to 0.2M. In one embodiment, the molar concentration ratio of the total amine groups of the amine compound to the metal ions of the metal salt compound is 1.5 to 10. In one embodiment, the concentration of the water-soluble polymer is 0.5×10 -3 M to 1.0×10-1 It is M. In one embodiment, based on the total weight of the composition solution for generating the photosensitive dry film, the content of the photocatalyst precursor is 0.1% to 3.0%.

[0026] Thereafter, an adhesive layer 202 is formed on the substrate 200. Here, the adhesive layer 202 and the photocatalyst formed thereafter may be made of the same or different materials. In the case of the same material, it is advantageous for the adhesion of the photocatalyst to the surface of the adhesive layer. For example, the adhesive layer 202 may be titanium dioxide, zinc oxide, silane, self-assembly monolayer (SAM), polydopamine, etc. Thereafter, a composition solution for generating a photosensitive dry film is applied to the surface of the adhesive layer 202, and after drying, a photosensitive dry film 204 is formed, and photocatalyst particles are deposited in the photosensitive dry film 204.

[0027] Next, a local area or the entire area of the photosensitive dry film 204 is exposed. For example, by means of a photomask 206 or a digital exposure method, a local area 204' of the photosensitive dry film 204 is exposed 208 to induce the photocatalyst in the photosensitive dry film 204 to generate electron-hole pairs. Thereby, on the surface of the photocatalyst, metal particles in the metal complex are reduced, and the effect of selectively reducing and depositing the metal particles is achieved. Also, during exposure, not only are metal particles reduced on the surface of the photocatalyst, but metal ions in the metal complex are also reduced within the photocatalyst, and the above metal particles are doped within the photocatalyst to form a mixed structure.

[0028] Since the photocatalyst in the unexposed photosensitive dry film 204 does not generate electron-hole pairs, the catalyst-forming composition in this case still contains a metal complex and a water-soluble polymer that can be removed with a detergent. Therefore, the unexposed photosensitive dry film 204 outside the local region 204' can be removed by methods such as detergents. At the same time, the unreacted metal complex and water-soluble polymer in the local region 204' are also removed, leaving metal particles and a photocatalyst. For example, rinsing with deionized water (DI) or using an aqueous solution of an amine compound (such as triethanolamine (TEA), diethanolamine (DEA), etc.) having a Pd chelating effect gives more favorable results. Thereafter, electroless plating is performed using the metal particles deposited in the local region 204' as a catalyst to form a metal layer 210. Here, the metal layer 210 may be a copper layer or a nickel layer. The patterned circuit layer after electroless plating includes the metal layer 210 and a patterning catalyst layer (i.e., the catalyst in the local region 204').

[0029] According to the method of this embodiment, a photosensitive dry film 204 is formed on the substrate 200, and then, when electroless plating is required, a catalyst (metal particles) can be deposited by the method of exposure 208, so that the oxidation of the catalyst can be significantly reduced, whereby cheaper metal copper particles can be used as a catalyst for electroless copper plating. In another embodiment, palladium metal particles may be used as a catalyst for electroless nickel plating.

[0030] FIG. 3 is a schematic cross-sectional view showing an electroless plating flow of a metal layer according to still another embodiment of the present invention. Here, the same or similar parts and components are denoted by the same reference numerals as in the foregoing embodiments. Also, since the content related to the same or similar parts and components can refer to the content of the foregoing embodiments, the description is omitted.

[0031] Referring to FIG. 3, the difference between the method of this embodiment and the above embodiment is that after forming the adhesive layer 202 on the substrate 200, ink is prepared using a composition solution for generating a photosensitive dry film, and a patterned photosensitive dry film 300 is directly formed on the surface of the adhesive layer 202 by methods such as screen printing, inkjet printing, or gravure printing. Therefore, as long as the subsequent exposure 302 is performed comprehensively without using a device such as a photomask, the photocatalyst inside the patterned photosensitive dry film 300 can be induced to generate electron-hole pairs. Thereby, metal particles are reduced on the surface of the photocatalyst to obtain the photosensitive dry film 300' after exposure. Then, electroless plating can be performed using the metal particles deposited in the photosensitive dry film 300' after exposure as a catalyst to form the metal layer 210.

[0032] FIG. 4 is a schematic cross-sectional view showing an electroless plating flow of a metal layer according to still another embodiment of the present invention. Here, the same or similar parts and components are denoted by the same reference numerals as those in the embodiment of FIG. 2. Since the content related to the same or similar parts and components can refer to the content of the embodiment of FIG. 2, the description thereof is omitted.

[0033] Referring to FIG. 4, the difference between the method of this embodiment and the embodiment of FIG. 2 is that after forming the adhesive layer 202 on the substrate 200 and applying and drying a composition solution for generating a photosensitive dry film on the surface of the adhesive layer 202, separately, a barrier structure 400 is formed on the surface of the photosensitive dry film 204 to expose a part of the photosensitive dry film 204. Here, the barrier structure 400 is made of a photosensitive polymer such as, for example, photoresist or photosensitive polyimide (PSPI) that can be patterned. Further, the method of forming the barrier structure 400 is, for example, screen printing, inkjet printing, or photolithography, but is not limited thereto.

[0034] Thereafter, the entire area of the photosensitive dry film 204 is exposed 302 to induce the photocatalyst in the photosensitive dry film 204 to generate electron-hole pairs, and metal particles are reduced and deposited on the surface of the photocatalyst in the local area 204'.

[0035] Thereafter, electroless plating is performed using the metal particles deposited in the local area 204' as a catalyst to form a metal layer 210. After electroless plating, the barrier structure 400 can be maintained. Since this embodiment has the barrier structure 400, the metal layer 210 can be maintained within the set area through the barrier structure 400. Therefore, the method of this embodiment can be applied to metal layer patterns that require higher resolution.

[0036] Several experiments for verifying the effectiveness of the present invention are listed below, but the present invention is not limited to the following content.

[0037] Experimental Example 1

[0038] First, a composition solution for generating a photosensitive dry film was prepared. The raw materials used are as follows. Metal salt compound: Copper acetate Concentration: 0.1 M. Amine compound: Triethanolamine (TEA) Concentration: 0.1 M. Amine group (amine) / Cu molar ratio of TEA to copper acetate 3. Photocatalyst precursor: Titanium butoxide (Ti(OBu)4) 0.5 wt%. Water-soluble polymer: PVA 0.5 wt%. Solvent: Methanol. (All of the above raw materials used chemical reagents provided by Alfa Aesar, Merck, and Aldrich)

[0039] Pretreatment of the glass substrate: 0.5 wt% of titanium butoxide was added to butanol to form a slurry, which was spin-coated on the glass substrate at a speed of 2000 rpm, dried at 120°C, and calcined in air at 400°C for 1 hour to obtain a TiO2 adhesion layer with a thickness of about 2 - 20 nanometers.

[0040] Next, a composition solution for generating a photosensitive dry film was spin-coated on the TiO2 adhesive layer of a glass substrate at a speed of 2000 rpm and dried at 120 °C to obtain a photosensitive dry film with a thickness of about 0.5 to 10 micrometers.

[0041] Preparation of copper plating bath: After mixing copper sulfate (2.5 g / mL) and formaldehyde (6 mL / L) to form a solution, its pH value was adjusted to about 12.5 to form a copper plating bath for electroless copper plating.

[0042] Next, when the photosensitive dry film on the substrate was irradiated with UV light (185 & 254 nm, 80 W) for 15 minutes, it was visually observed that not only did the color of the photosensitive dry film change, but also black solid fine particles adhering to it were generated. Then, the entire substrate was immersed in the above copper plating bath for 10 minutes, and the temperature was controlled at 55 °C to 60 °C. It was observed that the substrate immediately became darker, and with the generation of bubbles, a complete electroless copper plating reaction started. After 10 minutes of immersion plating, the glass substrate became opaque due to copper plating.

[0043] Experimental Example 2

[0044] The same production method as in Experimental Example 1 was adopted, but copper acetate in the composition solution for generating the photosensitive dry film was changed to copper formate, and triethanolamine in the composition solution for generating the photosensitive dry film was changed to ethanolamine (MEA) (using chemical reagents provided by Alfa Aesar, Merck, and Aldrich).

[0045] After UV light irradiation, it was similarly observed that the color of the photosensitive dry film changed and black solid fine particles adhering to it were generated. After electroless plating, it was observed that the glass substrate became opaque due to copper plating.

[0046] Comparative Example 1

[0047] The same production method as in Experimental Example 1 was adopted, but no water-soluble polymer was added to the composition solution for generating the photosensitive dry film, and the solvent was changed to ethanol (using chemical reagents provided by Alfa Aesar, Merck, and Aldrich).

[0048] After UV light irradiation, the complex changed to yellow. However, it was observed that most of the applied dry film disappeared after electroless plating. That is, in Comparative Example 1, the photoreduction reaction was not completed, and the unreacted complex detached from the substrate and dissolved in the copper plating bath. It can be seen that simply adding a photocatalyst is insufficient to generate sufficiently active copper metal particles and cannot effectively induce copper plating.

[0049] Comparative Example 2

[0050] The same production method as in Experimental Example 1 was adopted, but no photocatalyst precursor was added to the composition solution for generating the photosensitive dry film, the proportion of PVA was 1.0 wt%, and the solvent was changed to ethanol.

[0051] After UV light irradiation and electroless plating, the phenomenon of copper plating was not observed. That is, in Comparative Example 2, since photocatalyst particles were not generated, the action of photoreduction was insufficient, and basically, the deposition of catalyst fine particles was not formed.

[0052] Experimental Example 3

[0053] First, composition solutions for generating the following four groups of photosensitive dry films were prepared. (All of the following raw materials used chemical reagents provided by Alfa Aesar, Merck, and Aldrich)

[0054] The first group (adding only a photosensitizer): copper formate (concentration: 0.1 M), 2-aminoisobutanol, benzophenone as a photosensitizer, and ethanol, and the amine / Cu molar ratio of 2-aminoisobutanol to copper formate is 2.

[0055] The second group (water-soluble polymer): copper formate (concentration: 0.1 M), 2-aminoisobutanol, PVA (concentration: 1.0×10 -2 M), and ethanol, and the amine / Cu molar ratio of 2-aminoisobutanol to copper formate is 2.

[0056] The third group (photocatalyst): copper formate (concentration: 0.1 M), 2-aminoisobutanol, titanium butoxide 0.5 wt%, and ethanol, and the amine / Cu molar ratio of 2-aminoisobutanol to copper formate is 2.

[0057] The fourth group (water-soluble polymer and photocatalyst): copper formate (concentration: 0.1 M), 2-aminoisobutanol, titanium butoxide 0.5 wt%, PVA (concentration: 1.0×10 -2 M), and ethanol, and the amine / Cu molar ratio of 2-aminoisobutanol to copper formate is 2.

[0058] Using the method of Experimental Example 1, first, a TiO2 adhesion layer was formed on a glass substrate, and then a photosensitive dry film was formed using the composition solutions for generating the above four different groups of photosensitive dry films, respectively, and irradiated with UV light (185&254 nm 80W) for 20 minutes, but electroless plating was not performed.

[0059] For the four groups of samples after light irradiation, an ultraviolet-visible light (UV-vis) transmittance test was performed, and the results are shown in Figure 5.

[0060] As can be seen from Fig. 5, the following can be understood. When only the photosensitizer was used, it did not contribute to the precipitation of copper metal particles. When only the water-soluble polymer was added or only the photocatalyst (TiO2) was formed, a significant reaction began to appear with respect to the UV light irradiation time. When the water-soluble polymer and the photocatalyst were present simultaneously, the reaction with respect to the UV light irradiation time was the most significant. Therefore, when 2-aminoisobutanol was used as the complexing agent and irradiated with UV light for 20 minutes, the light transmittance could be significantly reduced in the wavelength range from near ultraviolet light to visible light (330 nm to 600 nm). Such results indicate that the composition for forming a catalyst of the present invention is sufficient to induce the precipitation of a large amount of zero-valent copper metal particles and exhibits the effect of blocking light transmission.

[0061] Experimental Example 4

[0062] The same production method as in Experimental Example 3 was adopted, but the complexing agent was changed to ethylenediamine. The remaining raw materials, the formation of the adhesive layer and the photosensitive dry film, and the method of light irradiation (for 10 minutes) were all the same as in Experimental Example 3.

[0063] Thereafter, a transmittance test was performed on the 4 groups of samples after light irradiation, and the results are shown in Fig. 6.

[0064] Similarly, as can be seen from Fig. 6, even when only the photosensitizer was added, it did not contribute to the precipitation of copper metal particles, and when the water-soluble polymer and the photocatalyst were present simultaneously, it can be seen that the light transmittance was the lowest. Therefore, even when the complexing agent was changed, metal particles were similarly precipitated after light irradiation. Furthermore, the light irradiation time in Experimental Example 4 using ethylenediamine was shorter than 20 minutes in Experimental Example 3, and as a result, the transmittance was even lower. Based on the difference in the chelating effect, it can be seen that each complexing agent exhibits a photoelectrochemical reduction reaction with different efficiencies. As shown in this experimental example, when ethylenediamine was used as the complexing agent, the effect of its photochemical reduction precipitation may be superior to that of 2-aminoisobutanol.

[0065] Experimental Example 5

[0066] The same production method as in Experimental Example 4 was adopted, and only the light irradiation time was simply changed. Thereafter, transmittance tests were performed on samples with different light irradiation times, and the results are shown in Fig. 7.

[0067] From Fig. 7, the following can be understood. The transmittance changed due to the difference in the light irradiation time. Here, the transmittance was the lowest when irradiated with light for 10 minutes. When the light irradiation time exceeded 10 minutes, presumably due to the aggregation of copper metal particles, the transmittance increased slightly, but the difference in morphology did not affect the effect of the metal particles inducing electroless copper plating. That is, as long as an appropriate light irradiation time was selected, the result of catalyst formation could be achieved.

[0068] Experimental Example 6

[0069] First, a composition solution for producing a photosensitive dry film was prepared. The raw materials used were as follows. Metal salt compound: Palladium acetate Concentration: 0.03 M. Amine compound: Propylenediamine Concentration: 0.03 M. Propylenediamine to palladium acetate amine / Pd molar ratio 2. Photocatalyst precursor: Titanium butoxide (Ti(OBu)4) 0.5 wt%. Water-soluble polymer: PEG Concentration: 1.0×10 -2 M. Solvent: Isopropyl alcohol. (All of the above raw materials used chemical reagents provided by Alfa Aesar, Merck, and Aldrich)

[0070] Thereafter, 0.5 wt% of titanium butoxide was added to butanol to form a slurry, which was spin-coated on a glass substrate at a speed of 2000 rpm, dried at 120°C, and calcined in air at 400°C for 1 hour to obtain a TiO2 adhesion layer with a thickness of about 2 - 20 nanometers.

[0071] Next, the composition solution for producing the photosensitive dry film was spin-coated onto the TiO2 adhesive layer of the glass substrate at a speed of 2000 rpm and dried at 120 °C to obtain a photosensitive dry film with a thickness of about 0.5 to 10 micrometers. The above process was repeated to fabricate another substrate with a photosensitive dry film.

[0072] Next, using UV light (365 nm, 200 W), the photosensitive dry films on different substrates were irradiated for 5 minutes and 10 minutes, respectively. It was observed that the Pd complex changed significantly upon 5-minute light irradiation and was confirmed to have catalytic activity for copper chemical deposition. Transmittance tests were performed on samples with different light irradiation times, and the results are shown in Figure 8.

[0073] From Figure 8, the following can be understood. When changing to different metal salt compounds, metal particles were deposited after light irradiation. Furthermore, palladium has higher photosensitivity and stronger photoreactivity compared to copper, so the light irradiation time could be shortened.

[0074] Experimental Example 7

[0075] First, a composition solution for producing a photosensitive dry film was prepared. The raw materials used are as follows. Metal salt compound: Copper acetate Concentration: 0.1 M. Amine compound: Triethanolamine (TEA) Concentration: 0.1 M. Amine / Cu molar ratio of TEA to copper acetate 2. Photocatalyst precursor: Titanium butoxide (Ti(OBu)4) 0.5 wt%. Water-soluble polymer: PVA Concentration: 0.5×10 -3 M. Solvent: Isopropyl alcohol. (All of the above raw materials used chemical reagents provided by Alfa Aesar, Merck, and Aldrich.)

[0076] Pretreatment of the glass substrate: 0.5 wt% of titanium butoxide was added to butanol to form a slurry, which was spin-coated onto the glass substrate at a speed of 2000 rpm, dried at 120 °C, and calcined in air at 400 °C for 1 hour to obtain a TiO2 adhesion layer with a thickness of about 2 - 20 nanometers.

[0077] Preparation of the copper plating bath: After mixing copper sulfate (2.5 g / mL) and formaldehyde (6 mL / L) to form a solution, its pH value was adjusted to about 12.5 to form a copper plating bath for electroless copper plating.

[0078] Next, the composition solution for generating the photosensitive dry film was spin-coated onto the TiO2 adhesion layer of the glass substrate at a speed of 2000 rpm and dried at 120 °C to obtain a photosensitive dry film with a thickness of about 0.5 - 10 micrometers.

[0079] The substrate coated with the copper complex was dried in an oven at 100 °C for 5 minutes and covered with a stainless steel photomask. The photomask pattern was parallel lines with a line width / line spacing L / S = 100 / 100 and 80 μm / 80 μm. After irradiating with UV light (185 & 254 nm, 80 W) for 15 minutes, it was rinsed with deionized water (DI) to remove the excess catalyst, and then the entire substrate was immersed in the above copper plating bath for 10 minutes, controlling the temperature at 55 °C - 60 °C.

[0080] Observation showed that in the non-irradiated areas, the deposits did not adhere, so they were removed with deionized water to obtain a resolved pattern. Limited to the photomask size, after testing with L / S = 100 / 100 and L / S = 80 / 80, the pattern could be clearly resolved.

[0081] Experimental Example 8

[0082] First, a composition solution for generating the photosensitive dry film was prepared. The raw materials used were as follows. Metal salt compound: Copper acetate Concentration: 0.05 M. Amine compounds: (Group 1) 2 - amino - 2 - methyl - 1 - propanol; (Group 2) isopropanolamine; (Group 3) 1 - octylamine; (Group 4) ethylenediamine; (Group 5) propylenediamine. The concentration of each is 0.15 M. The amine / Cu molar ratio of the amine compound to copper acetate is 3. Photocatalyst precursor: titanium butoxide 0.5 wt%. Water - soluble polymer: PVP Concentration: 0.5×10 -3 M. Solvent: ethanol. (All of the above raw materials used chemical reagents provided by Alfa Aesar, Merck, and Aldrich)

[0083] Pretreatment of the glass substrate: Titanium butoxide 0.5 wt% was added to butanol to form a slurry, which was spin - coated onto the glass substrate at a speed of 2000 rpm, dried at 120 °C, and calcined in air at 400 °C for 1 hour to obtain a TiO2 adhesion layer with a thickness of about 2 - 20 nanometers.

[0084] Next, a composition solution for generating 5 groups of photosensitive dry films containing different amine compounds was spin - coated onto the TiO2 adhesion layer of the glass substrate at a speed of 2000 rpm, dried at 120 °C, to obtain a photosensitive dry film with a thickness of about 0.5 - 10 micrometers.

[0085] Preparation of the copper plating bath: Copper sulfate (2.5 g / mL) and formaldehyde (6 mL / L) were mixed to form a solution, and then its pH value was adjusted to about 12.5 to form a copper plating bath for electroless copper plating.

[0086] Next, when the photosensitive dry film on the substrate was irradiated with UV light (185 & 254 nm, 80 W) for 15 minutes, it was observed that the color of the photosensitive dry film changed, and black solid fine particles adhering thereto were generated. Subsequently, the entire substrate was immersed in the copper plating bath for 10 minutes, and the temperature was controlled at 55°C to 60°C. It was observed that all the composition solutions for generating 5 groups of photosensitive dry films containing different amine compounds could form a copper metal layer by electroless plating after light irradiation. Therefore, the types of complexing agents (amine compounds) employed in this test do not have a significant impact on the formation of copper metal particles, and all can utilize the mechanism of photoreduction to induce the reduction and precipitation of copper metal particles. It was verified that the copper metal particles generated by each amine compound all have the activity to induce the deposition of electroless copper.

[0087] As described above, the present invention has been disclosed through the embodiments, but these are not intended to limit the present invention. Those with ordinary knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be determined by the scope of the attached patent application.

Industrial Applicability

[0088] The photosensitive dry film of the present invention, the composition solution for generating the same, and the method for electroless plating of the metal layer can all be applied to devices having an electroless metal plating layer.

Explanation of Reference Numerals

[0089] 100: Structure after light irradiation 102: Photocatalyst 104: Metal particles 106: Water-soluble polymer 200: Substrate 202: Adhesive layer 204: Photosensitive dry film 204’: Local area 206: Photomask 208: Exposure 210: Metal layer 300: Patterned photosensitive dry film 300’: Photosensitive dry film after exposure 302: Exposure 400: Barrier structure e - : Electron h + : Hole

Claims

1. A composition for forming a catalyst, comprising a metal complex and a water-soluble polymer, and a photocatalyst which is a precipitate after drying a photocatalyst precursor and is dispersed in the composition for forming a catalyst. A photosensitive dry film comprising the above.

2. The photosensitive dry film according to claim 1, which is formed by applying and drying a composition solution for producing the photosensitive dry film.

3. The metal complex is a reaction product of an amine compound and a metal salt compound, and the molar concentration ratio of the total amine groups of the amine compound to the metal ions of the metal salt compound is 1.5 to 10. The photosensitive dry film according to claim 1.

4. The photocatalyst comprises titanium dioxide, zinc oxide or a combination thereof. The photosensitive dry film according to claim 1.

5. Based on the total weight of the photosensitive dry film, the content of the photocatalyst is 1% to 70%. The photosensitive dry film according to claim 1.

6. A metal salt compound, an amine compound as a complexing agent, a photocatalyst precursor, a water-soluble polymer, and a solvent. A composition solution for producing a photosensitive dry film, comprising the above.

7. The metal salt compound is one or more mixtures selected from the group consisting of metal sulfates, metal nitrates, metal acetates, metal formates, and metal chloride salts. The metal is nickel, copper, palladium or silver. The composition solution for producing the photosensitive dry film according to claim 6.

8. The amine compound is at least one selected from the group consisting of ethanolamine, triethanolamine, ethylenediamine, propylenediamine (1,2-diaminopropane), dimethylamine, 2-aminoisobutanol (2-Amino-2-methyl-1-propanol), isopropanolamine (1-Amino-2-propanol), and 1-octylamine. The composition solution for producing the photosensitive dry film according to claim 6.

9. The molar concentration ratio of the total amine groups of the amine compound to the metal ions of the metal salt compound is 1.5 to 10. The composition solution for producing the photosensitive dry film according to claim 6.

10. ​ The water-soluble polymer includes polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polyethylene glycol (PEG), polyethyleneimine (PEI), methyl cellulose, gelatin, starch, chitosan, or a combination thereof. A composition solution for producing the photosensitive dry film according to claim 6.

11. The photocatalyst precursor includes titanium isopropoxide, titanium butoxide, zinc methoxide, zinc propoxide, or a combination thereof. A composition solution for producing the photosensitive dry film according to claim 6.

12. Based on the total weight of the composition solution, the content of the photocatalyst precursor is 0.1% to 3.0%. A composition solution for producing the photosensitive dry film according to claim 6.

13. Preparing a composition solution for producing the photosensitive dry film according to any one of claims 6 to 12, including a metal salt compound, an amine compound as a complexing agent, a photocatalyst precursor, a water-soluble polymer, and a solvent; Providing a substrate and forming an adhesive layer on the substrate; Coating the composition solution on the surface of the adhesive layer; Drying the composition solution to form a photosensitive dry film, wherein the photosensitive dry film includes a composition for catalyst formation and a photocatalyst dispersed in the composition for catalyst formation, the composition for catalyst formation includes a metal complex and the water-soluble polymer, and the photocatalyst is a precipitate after drying the photocatalyst precursor, the forming; Exposing a local region or the entire region of the photosensitive dry film to induce the photocatalyst to generate electron-hole pairs, and reducing the metal complex on the surface of the photocatalyst to generate metal particles; Performing electroless plating using the metal particles as a catalyst to form a metal layer; An electroless plating method for a metal layer, including.

14. The metal complex is formed by a complex reaction between the amine compound and the metal salt compound in the composition solution. In the photosensitive dry film, the molar concentration ratio of the total amine groups of the amine compound to the metal ions of the metal salt compound is 1.5 to 10. The electroless plating method for a metal layer according to claim 13.

15. The metal layer includes a copper layer or a nickel layer. The electroless plating method for a metal layer according to claim 13.

16. The step of performing the exposure includes reducing metal ions in the metal complex within the photocatalyst to form the metal particles and doping the metal particles into the photocatalyst. The electroless plating method of the metal layer according to claim 13.

17. The method of applying the composition solution includes screen printing, inkjet printing, or gravure printing for forming a pattern on the surface of the adhesive layer. The electroless plating method of the metal layer according to claim 13.

18. The method of performing exposure on the local region of the photosensitive dry film includes selectively reducing and depositing the metal particles by a method of a photomask or digital exposure. The electroless plating method of the metal layer according to claim 13.

19. After exposing the local region of the photosensitive dry film, it further includes removing the unexposed photosensitive dry film outside the local region. The electroless plating method of the metal layer according to claim 13.

20. After forming the photosensitive dry film, it further includes forming a barrier structure on the surface of the photosensitive dry film and exposing a local region of the photosensitive dry film. The electroless plating method of the metal layer according to claim 13.

21. The adhesive layer and the photocatalyst are made of the same or different materials. The electroless plating method of the metal layer according to claim 13.

22. The molar concentration of the metal salt compound is 0.01 M to 0.2 M. The electroless plating method of the metal layer according to claim 13.

23. The molar concentration ratio of the total amine groups of the amine compound to the metal ions of the metal salt compound is 1.5 to 10. The electroless plating method of the metal layer according to claim 13.

24. The concentration of the water-soluble polymer is 0.5 × 10 －３ M to 1.0 × 10 －１ M, The electroless plating method of the metal layer according to claim 13.

25. Based on the total weight of the composition solution, the content of the photocatalyst precursor is 0.1% to 3.0%. The electroless plating method of the metal layer according to claim 13.

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