CN115707191A - Conductive circuit structure and manufacturing method thereof - Google Patents

Abstract

The invention provides a method for manufacturing a conducting circuit structure, which comprises the following steps: providing a substrate; coating a non-conductive photoresist on the substrate; coating a palladium salt deposit on the side of the non-conductive photoresist far away from the substrate; simultaneously exposing the non-conductive photoresist and the palladium salt deposit to form an exposed pattern; developing the exposed pattern to form a wiring pattern; and replacing the palladium salt deposit with metal ions to form the conductive line. In addition, the invention also provides a conducting circuit structure. The technical scheme of the invention has simple process steps and greatly reduces the cost.

Description

Conductive circuit structure and manufacturing method thereof

Technical Field

The invention relates to the technical field of conductive circuit manufacturing, in particular to a conductive circuit structure and a manufacturing method thereof.

Background

The traditional method for manufacturing the conductive circuit is to compound, vacuum-coat or coat a layer of conductive material on a transparent or non-transparent bearing substrate, and then make the conductive material into the conductive circuit through the procedures of exposure, development, etching, film removal and the like. The manufacturing method has the disadvantages of multiple steps, high material cost and manufacturing cost, low yield and huge cost pressure because the conductive material has the risk of peeling off and separating from the surface of the bearing substrate.

Disclosure of Invention

The invention provides a conducting circuit structure and a manufacturing method thereof, which have simple process steps and greatly reduce the cost.

In a first aspect, an embodiment of the present invention provides a method for manufacturing a conductive circuit structure, where the method for manufacturing the conductive circuit structure includes:

providing a substrate;

coating a non-conductive photoresist on the substrate;

coating a palladium salt deposit on the non-conductive photoresist far away from the substrate;

simultaneously exposing the non-conductive photoresist and the palladium salt deposit to form an exposed pattern;

developing the exposed pattern to form a line pattern; and

and replacing the palladium salt deposit by metal ions to form a conductive circuit.

Preferably, after the palladium salt deposit is replaced by metal ions to form the conductive circuit, the method for manufacturing the conductive circuit structure further includes:

and thickening the conductive circuit to obtain a reinforced conductive circuit.

Preferably, the thickening the conductive circuit to obtain a reinforced conductive circuit specifically includes:

and carrying out chemical copper plating on the conductive circuit.

Preferably, after the conductive circuit is thickened to obtain an enhanced conductive circuit, the method for manufacturing the conductive circuit structure further includes:

and coloring the enhanced conductive circuit to make the color of the enhanced conductive circuit matched with the color of the substrate.

Preferably, the coloring treatment of the reinforcing conductive circuit specifically includes:

and carrying out blackening treatment on the enhanced conducting circuit.

Preferably, the non-conductive photoresist includes a dispersant, a developing resin, a photocurable resin, a photoinitiator, and a catalyst.

Preferably, the size of the metal ions is 20 nm to 50 μm.

Preferably, the coating of the non-conductive photoresist on the substrate specifically comprises:

and coating the non-conductive photoresist on one side or two sides of the substrate in a yellow environment, wherein the thickness of the non-conductive photoresist is more than 0.05-150 microns.

Preferably, the simultaneously exposing the non-conductive photoresist and the palladium salt deposit to form an exposure pattern specifically includes:

and irradiating the non-conductive photoresist and the palladium salt deposit by using light with a preset wavelength, wherein the preset wavelength is 300-460 nanometers.

In a second aspect, an embodiment of the invention provides a conductive circuit structure, where the conductive circuit structure is manufactured by the manufacturing method of the conductive circuit structure.

According to the conductive circuit structure and the manufacturing method thereof, the non-conductive photoresist is coated on the substrate, the palladium salt sediment is coated on the side, far away from the substrate, of the non-conductive photoresist, and the metal ions are utilized to replace the palladium salt sediment, so that the conductive circuit is formed, namely the conductive circuit is directly formed on the substrate, the process steps are simple, and the cost is greatly reduced. And the conductive circuit formed has better conductive performance and stable circuit structure. Because micron-level or even nano-level metal ions are adopted, the line width of the conductive circuit can reach finer micron level.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a flowchart of a method for manufacturing a conductive line structure according to an embodiment of the present invention.

Fig. 2 is a first sub-flowchart of a method for manufacturing a conductive line structure according to an embodiment of the invention.

Fig. 3 is a second sub-flowchart of a method for fabricating a conductive line structure according to an embodiment of the invention.

Fig. 4 is a schematic diagram illustrating a method for manufacturing a conductive line structure according to an embodiment of the invention.

Fig. 5 is a schematic diagram of a conductive line structure according to an embodiment of the invention.

The implementation, functional features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the present application and in the above-described drawings (if any) are used for distinguishing between similar items and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged under appropriate circumstances, in other words, the described embodiments may be practiced other than as illustrated or described herein. Moreover, the terms "comprises," "comprising," and any variations thereof, may also encompass other things, such as processes, methods, systems, articles, or apparatus that comprise a list of steps or elements, but not necessarily limited to only those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such processes, methods, articles, or apparatus.

It should be noted that the description relating to "first", "second", etc. in the present invention is for descriptive purposes only and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

Referring to fig. 1, fig. 4 and fig. 5 in combination, fig. 1 is a flowchart of a method for manufacturing a conductive line structure according to an embodiment of the present invention, fig. 4 is a schematic diagram of a method for manufacturing a conductive line structure according to an embodiment of the present invention, and fig. 5 is a schematic diagram of a conductive line structure according to an embodiment of the present invention. The conductive Circuit structure 1000 may be applied to an electronic device such as a Flexible Printed Circuit (FPC), a Printed Circuit Board (PCB), a display screen, and a touch panel. When the conductive trace structure 1000 is applied to a touch panel, the touch panel may be formed by an integrated touch (OGS), an On-cell, an In-cell, or the like. The method for manufacturing the conductive circuit structure specifically comprises the following steps.

Step S102, providing a substrate. In the present embodiment, the substrate 10 includes, but is not limited to, a flexible substrate and a non-flexible substrate. Among them, materials of which the flexible substrate is made include, but are not limited to, polyethylene terephthalate (PET), transparent polyimide (CPI), modified Polyimide (MPI), polyethylene naphthalate (PEN), cycloolefin Polymer (COP), and the like, and the non-flexible substrate includes, but is not limited to, a PCB, an aluminum alloy coated with an insulating resin, and the like. It is understood that the substrate 10 is an insulating substrate regardless of whether the substrate 10 is a flexible substrate or a non-flexible substrate. Even if a non-insulating base material such as an aluminum alloy or the like is used for the substrate 10, an insulating layer needs to be applied to the surface of the non-insulating base material to form an insulating substrate.

In step S104, a non-conductive photoresist is coated on the substrate. In this embodiment, the non-conductive photoresist 20 is coated on one side or both sides of the substrate 10 in a yellow environment. It is understood that the non-conductive photoresist 20 is a photosensitive material that does not contain a conductive material and cannot be used for conduction. Wherein, the thickness of the non-conductive photoresist 20 is more than 0.05-150 microns. In the present embodiment, the non-conductive photoresist 20 includes a dispersant, a developing resin, a photocurable resin, a photoinitiator, and a catalyst. After the non-conductive photoresist 20 is coated on the substrate 10, the substrate 10 coated with the non-conductive photoresist 20 is heated. Preferably, the baking is carried out in a yellow environment at 60-135 ℃ for a period of less than 6 minutes. After the heating is completed, the substrate 10 coated with the non-conductive photoresist 20 is cooled.

In step S106, a palladium salt deposit is coated on the non-conductive photoresist on the side away from the substrate. It is understood that when the non-conductive photoresist 20 is coated on the side of the substrate 10, the palladium salt deposit 30 is coated on the side of the substrate 10 where the non-conductive photoresist 20 is located; when the non-conductive photoresist 20 is coated on both sides of the substrate 10, the palladium salt deposits 30 are respectively coated on both sides of the substrate 10. The palladium salt deposit 30 is a mixture of palladium salts including, but not limited to, palladium chloride, palladium nitrate, palladium sulfate, etc. The palladium salt deposit 30 is applied at a thickness of 0.1-20 microns.

In step S108, the non-conductive photoresist and the palladium salt deposit are exposed to form an exposure pattern. In the present embodiment, the non-conductive photoresist 20 and the palladium salt deposit 30 are irradiated with light of a predetermined wavelength. Wherein the preset wavelength is 300-460 nm. Preferably, the predetermined wavelength is 365 nm. It can be understood that, during the exposure process, the light with the predetermined wavelength irradiates the non-conductive photoresist 20 and the palladium salt deposit 30 through the mask with the predetermined pattern, the non-conductive photoresist 20 after being irradiated by the light with the predetermined wavelength is cured on the substrate 10, and the palladium salt deposit 30 is cured on the side of the non-conductive photoresist 20 away from the substrate 10, so as to form the exposure pattern identical to the predetermined pattern. Wherein the exposure energy is 75-400mJ/cm ² The thickness of the formed exposure pattern is 0.01-100 micrometers, and the line width is 0.5-300 micrometers.

In step S110, the exposed pattern is developed to form a wiring pattern. In the present embodiment, the non-conductive photoresist 20 and the palladium salt deposit 30 cured on the substrate 10 without exposure are washed away using a developing solution. It is understood that while the uncured non-conductive resist 20 and palladium salt deposits 30 are washed away, the remaining non-conductive resist 20 cured on the substrate 10 and the palladium salt deposits 30 cured on one side of the non-conductive resist 20 collectively form a line pattern. Wherein the line width of the circuit pattern is 0.7-400 microns. The developing solution includes, but is not limited to, alkaline compound solutions such as sodium hydroxide and potassium hydroxide. Preferably, the developer is a sodium hydroxide solution containing 0.01% -1.65% of tetramethylammonium hydroxide (TMAH) and the development time is 0.3-15 minutes.

In step S112, the palladium salt deposit is replaced by the metal ions to form the conductive traces. Wherein the size of the metal ions 40 is 20 nanometers to 50 micrometers. The metal ions 40 include, but are not limited to, silver ions, copper ions, and the like. It is understood that the pattern formed by the non-conductive resist 20 and the palladium salt deposit 30 is not conductive, and after the palladium salt deposit 30 is replaced by the metal ions 40, the metal ions 40 adhere to the side of the non-conductive resist 20 away from the substrate 10 to form the conductive line 400 having conductivity.

When the non-conductive photoresist 20 is coated on one side of the substrate 10, the metal ions 40 may form a conductive line 400 on one side of the substrate 10; when the non-conductive photoresist is coated on both sides of the substrate 10, the metal ions 40 can form the conductive traces 400 on both sides of the substrate 10.

In the embodiment, the non-conductive photoresist is coated on the substrate, the palladium salt deposit is coated on the side of the non-conductive photoresist far away from the substrate, and the palladium salt deposit is replaced by the metal ions, so that the conductive circuit is formed, namely the conductive circuit is directly formed on the substrate, the process steps are simple, and the cost is greatly reduced. And the conductive circuit formed has better conductive performance and stable circuit structure. Because micron-level or even nano-level metal ions are adopted, the line width of the conductive circuit can reach finer micron level. Meanwhile, the non-conductive photoresist is coated on one side or two sides of the substrate, so that the structure of a single-sided conductive circuit or a double-sided conductive circuit can be realized, and the manufactured conductive circuit structure has wide application scenes.

In addition, a layer of conductive circuit can be formed on one side of the substrate; or forming multiple layers of conductive circuits on one side of the substrate by repeatedly performing steps S104-S112, wherein the multiple layers of conductive circuits can be insulated by using a transparent material and electrically connected by bridging; one conductive line or a plurality of conductive lines may be formed on both sides of the substrate.

In some possible embodiments, the non-conductive photoresist 20 and the palladium salt deposit 30 that form the line pattern may be activated before performing step S112.

Specifically, the non-conductive photoresist 20 and the palladium salt deposit 30 are activated using a colloidal palladium activation solution. The components and parts by weight of the colloidal palladium activating solution are shown in the following table.

When the colloidal palladium activation solution of formula 1 is used to activate the nonconductive photoresist 20 and the palladium salt deposit 30, the operating conditions are as follows: the temperature is 18-35 ℃, the time is 1-5 minutes, and the pH value is less than or equal to 0.1. When the colloidal palladium activation solution of formulation 2 is used to activate the nonconductive photoresist 20 and the palladium salt deposit 30, the operating conditions are as follows: the temperature is 18-35 ℃, the time is 1-5 minutes, and the pH value is 0.7-0.8.

In other possible embodiments, the non-conductive photoresist 20 and the palladium salt deposit 30 may be activated by other components or parts by weight of the colloidal palladium activation solution, and the non-conductive photoresist 20 and the palladium salt deposit 30 may also be activated by other activation methods such as sensitization activation, which are not limited herein.

Activation of the non-conductive photoresist and the palladium salt deposit enables metal ions to better displace the palladium salt deposit, enabling the metal ions to better adhere to the non-conductive photoresist, thereby forming a more stable conductive circuit.

Please refer to fig. 2, which is a first sub-flowchart of a method for fabricating a conductive line structure according to an embodiment of the present invention. After step S112 is executed, the method for manufacturing the conductive circuit structure further includes the following steps.

Step S114, thickening the conductive trace to obtain an enhanced conductive trace. In this embodiment, electroless copper plating is performed on the conductive trace 400, so that a layer of copper plating 50 is formed on a side of the conductive trace 400 away from the substrate 10, thereby increasing the thickness of the conductive trace 400 to enhance the strength of the conductive trace 400, and thus obtaining the enhanced conductive trace 500. Reinforcing conductive traces 500 can make conductive traces 400 less prone to breakage, ensuring stability. Specifically, the conductive trace 400 is thickened using an electroless copper plating solution. The thickness of the copper plating 50 is 0.1 to 200 μm. The chemical copper plating solution comprises the following components in parts by weight.

When the chemical copper plating solution of formula 1 is used to thicken the conductive circuit 400, the operating conditions are as follows: the temperature is 21-25 deg.C, the deposition rate is 0.5 μm/h, the pH value is 12-13, and the work load is less than or equal to 1dm ² L, continuously filtering by stirring air. When the chemical copper plating solution of formula 2 is used to thicken the conductive circuit 400, the operating conditions are as follows: the temperature is 50-60 deg.C, the deposition rate is 4-5 μm/h, the pH value is 12-12.5, and the work load is less than or equal to 1dm ² L, continuously filtering by stirring air. When the chemical copper plating solution of formula 3 is used to thicken the conductive circuit 400, the operating conditions are as follows: the temperature is 35-40 deg.C, the deposition rate is 1-2 μm/h, the pH value is 12-13, and the work load is less than or equal to 2dm ² L, continuously filtering by stirring air.

In some possible embodiments, conductive trace 400 may be thickened using other compositions or weight parts of electroless copper plating solution. In other possible embodiments, the conductive line 400 may be thickened by electroplating, which is not limited herein.

In the above embodiment, the conductive circuit is thickened, so that the thickness of the conductive circuit is increased, the resistance value of the conductive circuit can be effectively ensured within the range of the process requirement, and the conductive stability of the conductive circuit can be enhanced. The chemical copper plating can thicken all conducting circuits at one time, obviously shorten the processing period and reduce the production cost. Moreover, the thickness of copper plating formed by chemical copper plating is uniform and consistent, and conductive circuits with small line widths can be thickened better.

In some possible embodiments, conductive line 400 is cleaned prior to thickening conductive line 400. The compositions and parts by weight of the cleaning solution are shown in the following table.

When conducting line 400 is cleaned with the cleaning solution of formulation 1 or formulation 2, the operating conditions are: the temperature was 50 ℃ and the time was 3 minutes, the stirring method was air stirring mechanical movement. When conducting line 400 is cleaned with the cleaning liquid of formulation 3, the operating conditions are: the temperature was 40 ℃ and the time was 3 minutes, the stirring method was air stirring mechanical movement.

In some possible embodiments, conductive trace 400 may be cleaned with other compositions or parts by weight of cleaning solution, and is not limited herein.

The cleaning can wash away impurities, such as resin, etc., from the surface of conductive trace 400 so that copper plating 50 can better bond to conductive trace 400 during electroless copper plating of conductive trace 400.

Please refer to fig. 3, which is a second sub-flowchart of a method for fabricating a conductive line structure according to an embodiment of the present invention. After step S114 is executed, the method for manufacturing the conductive circuit structure further includes the following steps.

Step S116, color the enhanced conductive traces to match the color of the substrate. Here, the reinforcing conductive traces 500 may be colored by means of electrolysis, so that a colored layer 60 is formed on the side of the copper plating 50 away from the substrate 10. The color layer 60 has the same color as the substrate 10.

When the substrate 10 is black or dark in color, the reinforcing conductive traces 500 may be subjected to a blackening treatment to form a black colored layer 60 on the side of the copper plating 50 away from the substrate 10. The blackening process can form a black oxide film on the surface of the copper plating layer 50 away from the substrate 10. The blackening treatment is to form a colored layer 60 on the surface of the copper plating 50 by using black nickel.

It is understood that step S116 is executed when there is a requirement for enhancing the color of the conductive trace 500; if there is no requirement for enhancing the color of the conductive traces 500, the step S116 need not be performed.

In the above embodiment, the color of the enhanced conductive circuit is matched with the color of the substrate by performing the coloring treatment on the enhanced conductive circuit, so that the whole structure of the conductive circuit has higher consistency.

Please refer to fig. 5, which is a schematic diagram of a conductive trace structure according to an embodiment of the invention. The conductive circuit structure 1000 is manufactured by the above-mentioned method for manufacturing a conductive circuit structure. It is understood that the conductive line configuration 1000 includes the substrate 10, the non-conductive resist 20, the reinforcing conductive line 500, and/or the colored layer 60, which are sequentially stacked. Since the conductive trace structure 1000 adopts all technical solutions of all the above embodiments, at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, and are not described in detail herein.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, to the extent that such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, it is intended that the present invention encompass such modifications and variations as well.

The above-mentioned embodiments are only examples of the present invention, which should not be construed as limiting the scope of the present invention, and therefore, the present invention is not limited by the claims.

Claims (10)

1. A method for manufacturing a conductive circuit structure is characterized by comprising the following steps:

providing a substrate;

coating a non-conductive photoresist on the substrate;

coating a palladium salt deposit on the non-conductive photoresist on the side away from the substrate;

simultaneously exposing the non-conductive photoresist and the palladium salt deposit to form an exposed pattern;

developing the exposed pattern to form a circuit pattern; and

and replacing the palladium salt deposit by metal ions to form the conductive circuit.

2. The method for fabricating an electrically conductive circuit structure according to claim 1, wherein after the palladium salt deposit is replaced with metal ions to form an electrically conductive circuit, the method for fabricating an electrically conductive circuit structure further comprises:

and thickening the conductive circuit to obtain a reinforced conductive circuit.

3. The method for manufacturing a conductive circuit structure according to claim 2, wherein the thickening the conductive circuit to obtain a reinforced conductive circuit specifically comprises:

and carrying out chemical copper plating on the conductive circuit.

4. The method for manufacturing a conductive circuit structure according to claim 2, wherein after the conductive circuit is thickened to obtain a reinforced conductive circuit, the method for manufacturing a conductive circuit structure further comprises:

and coloring the enhanced conductive circuit to make the color of the enhanced conductive circuit match with that of the substrate.

5. The method for manufacturing a conductive circuit structure according to claim 4, wherein the coloring the reinforcing conductive circuit specifically comprises:

and carrying out blackening treatment on the enhanced conducting circuit.

6. The method for forming an electrically conductive line structure according to claim 1, wherein the non-conductive photoresist comprises a dispersant, a developing resin, a photocurable resin, a photoinitiator, and a catalyst.

7. The method for forming an electrically conductive line structure according to claim 1, wherein the metal ions have a size of 20 nm to 50 μm.

8. The method for forming a conductive line structure according to claim 1, wherein the step of applying a non-conductive photoresist on the substrate comprises:

and coating the non-conductive photoresist on one side or two sides of the substrate in a yellow environment, wherein the thickness of the non-conductive photoresist is more than 0.05-150 microns.

9. The method for forming an electrically conductive circuit structure according to claim 1, wherein the step of simultaneously exposing the non-conductive photoresist and the palladium salt deposit to form an exposed pattern comprises:

and irradiating the non-conductive photoresist and the palladium salt deposit by using light with a preset wavelength, wherein the preset wavelength is 300-460 nanometers.

10. A conductive line structure, wherein the conductive line structure is manufactured by the method for manufacturing a conductive line structure according to any one of claims 1 to 9.

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