Conductive structure and method of making the same

Abstract

The application discloses a conductive structure and a manufacturing method thereof, and relates to the field of electronic additive technology.The manufacturing method comprises the following steps: providing an insulating base material with a through hole, the surface of the insulating base material and the inner wall of the through hole are not plated; printing an insulating seed layer on the insulating base material according to a target pattern by using an insulating plating ink; and forming a metal plating layer on the insulating seed layer by using a chemical plating process, the metal plating layer being consistent with the target pattern.The application can use a common insulating base material without doped organic metal compound, and can directly print the insulating plating ink on the surface of the insulating base material and the inner wall of the through hole by using an aerosol jet printing process, and then can obtain a metalized hole and a surface circuit by directly performing a chemical plating process, so that the application has the advantages of low cost and high efficiency, and the aerosol jet printing process can guarantee high precision of the circuit compared with a laser treatment process, and can meet the demand of high-precision circuit.

Description

Technical Field

[0001] This invention belongs to the field of electronic additive manufacturing technology, and particularly relates to a conductive structure and its fabrication method. Background Technology

[0002] Traditional LDS (Laser Direct Structuring) process uses laser-activated special plastic injection molding with organometallic composites, followed by laser patterning scanning to activate and expose the metal seed layer, and finally selectively deposits copper / nickel / gold to form conductive lines.

[0003] The emerging Lpum process (Laser Patterning Undoped Materials) uses undoped ordinary plastic injection molding. Special chemicals or plasma are used to impregnate the plastic to form a deactivating layer on the surface of the plastic, which inhibits the adsorption of non-circuit areas. Then, the deactivating layer in the circuit area is removed by laser patterning. An activator is then coated in the area to form an activation layer consistent with the circuit pattern. Finally, copper / nickel / gold is selectively deposited to form conductive circuits.

[0004] Traditional LDS processes are expensive, while emerging Lpum processes are complex, involve many steps, and have lower reliability and efficiency. Summary of the Invention

[0005] In view of this, one object of the present invention is to provide a conductive structure and a method for manufacturing the same, so as to solve the problems of high cost and complex process in the prior art.

[0006] In some illustrative embodiments, the method for fabricating the conductive structure includes: providing an insulating substrate with through holes, wherein neither the surface of the insulating substrate nor the inner wall of the through holes is plated; applying an insulating plated ink to the insulating substrate using an aerosol jet printing process to directly write and form a patterned insulating seed layer according to a target pattern, wherein the insulating seed layer is distributed on the surface of the insulating substrate and the inner wall of the through holes; and forming a metal plating layer consistent with the target pattern on the insulating seed layer using a chemical plating process.

[0007] In some optional embodiments, the insulating plating ink comprises: copper oxide particles and adhesive resin; wherein the particle size of the copper oxide particles is between 1 nm and 1.5 μm; and the solid content of the copper oxide particles in the insulating plating ink is not less than 40%.

[0008] In some alternative embodiments, the through hole includes a cylindrical through hole.

[0009] In some alternative embodiments, the process of forming a patterned insulating seed layer by directly writing the insulating plating ink onto the insulating substrate according to the target pattern using an aerosol jet printing process includes: adjusting the incident angle between the aerosol jet gas flow and the hole wall of the through hole to an acute angle range, thereby forming an insulating seed layer on the hole wall of the through hole.

[0010] In some alternative embodiments, the inner diameter of the cylindrical through-hole is not less than 400 μm.

[0011] In some alternative embodiments, the through hole includes a tapered through hole.

[0012] In some alternative embodiments, the process of forming a patterned insulating seed layer by directly writing the insulating plating ink onto the insulating substrate according to the target pattern using an aerosol jet printing process includes: placing the aerosol jetting airflow on the side of the insulating substrate with a larger orifice and directly facing the through-hole to form the insulating seed layer.

[0013] In some alternative embodiments, the insulating substrate has a planar structure or a three-dimensional structure.

[0014] In some alternative embodiments, the insulating substrate is rigid or flexible.

[0015] In some alternative embodiments, providing an insulating substrate with through holes includes: providing the insulating substrate; and creating the through holes in the insulating substrate by means of machinery or laser.

[0016] In some alternative embodiments, the thickness of the insulating seed layer is 2–20 μm.

[0017] Another object of the present invention is to provide a conductive structure to solve the problems in the prior art.

[0018] In some illustrative embodiments, the conductive structure is obtained by any of the fabrication methods described above.

[0019] Compared with the prior art, this application has the following advantages:

[0020] This invention can use ordinary insulating substrates without doped organometallic composites, and then use aerosol jet printing technology to directly spray patterned insulating ink onto the surface of the insulating substrate and the inner wall of the through holes. Finally, after chemical plating treatment, metallized holes and surface lines can be obtained simultaneously. It has the advantages of low cost and high efficiency. At the same time, compared with laser processing, the aerosol jet process also provides higher line accuracy, which can meet the needs of high-precision lines. Attached Figure Description

[0021] Figure 1 This is a flowchart example of the method for fabricating the conductive structure in an embodiment of the present invention;

[0022] Figure 2 This is a spray painting example for cylindrical through holes in an embodiment of the present invention;

[0023] Figure 3 This is an example of inkjet printing for tapered through-holes in an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that, where there is no conflict, the various technical features in the embodiments of the present invention can be combined with each other.

[0026] This invention discloses a method for fabricating a conductive structure, specifically, as follows: Figure 1-3 As shown, Figure 1 This is a flowchart example of the method for fabricating the conductive structure in an embodiment of the present invention; Figure 2 This is a spray painting example for cylindrical through holes in an embodiment of the present invention; Figure 3 This is an example of inkjet printing for a tapered through-hole in an embodiment of the present invention; the method for manufacturing the conductive structure includes:

[0027] Step S11: Provide an insulating substrate 1 with through holes 2, wherein the surface of the insulating substrate 1 itself and the inner wall of the through holes 2 are not plated.

[0028] Step S12: The insulating plating ink is directly printed on the insulating substrate according to the target pattern (i.e., the predetermined target circuit pattern) using the aerosol jet printing process 5 to form a patterned insulating seed layer 3. The insulating seed layer 3 is distributed on the surface of the insulating substrate 1 and the inner wall of the through hole 2.

[0029] Step S13: Form a metal plating layer 4 on the insulating seed layer 3 that matches the target pattern through a chemical plating process.

[0030] This invention can use ordinary insulating substrates without doped organometallic composites, and then use aerosol jet printing technology to directly spray patterned insulating ink onto the surface of the insulating substrate and the inner wall of the through holes. Finally, after chemical plating treatment, metallized holes and surface lines can be obtained simultaneously. It has the advantages of low cost and high efficiency. At the same time, compared with laser processing, the aerosol jet process also provides higher line accuracy, which can meet the needs of high-precision lines.

[0031] The insulating substrate in the embodiments of the present invention can be rigid or flexible. Rigid substrates include, but are not limited to: FR-4, CEM-1, 22F, CEM-3, wood, glass, plastic, PMMA (acrylic), etc. Flexible substrates include, but are not limited to: PET, PVC, PU, ​​PC, PP, PA, PI, CPI (transparent PI), TPE, TPU, TPV, etc.

[0032] In some embodiments, the insulating substrate has a planar structure or a three-dimensional structure.

[0033] In some embodiments, the insulating plating-compatible ink of the present invention may include: copper oxide particles and adhesive resin; wherein the particle size of the copper oxide particles is between 1 nm and 1.5 μm; and the solid content of the copper oxide particles in the insulating plating-compatible ink is not less than 40%. The insulating plating-compatible ink of the present invention refers to an ink that, after inkjet printing and curing, is itself insulating and can be chemically plated onto it to form a metallic coating. The solid particles in this ink are copper oxide, thus possessing the advantages of stable properties and low cost.

[0034] In some embodiments of the present invention, the through hole may include a cylindrical through hole. A cylindrical through hole refers to a through hole with a uniform inner diameter along its extension direction.

[0035] Specifically, when dealing with cylindrical through holes, the process of directly writing an insulating seed layer onto an insulating substrate using an aerosol jet printing process to form a patterned insulating seed layer includes: adjusting the incident angle between the aerosol jet airflow and the hole wall of the through hole to an acute angle range, thereby forming an insulating seed layer on the hole wall of the through hole.

[0036] The aerosol jet printing process is implemented based on an aerosol jet printer, which has a multi-axis motion mechanism. This multi-axis motion mechanism may include: a first transmission chain and a second transmission chain; the aerosol jet printhead is mounted on the first transmission chain, enabling independent movement of the printhead along the X-axis and Z-axis; the insulating substrate is mounted on the second transmission chain, enabling independent movement of the insulating substrate along the Y-axis, A-axis, and C-axis; wherein the A-axis is a rotational axis along the X-axis and the C-axis is a rotational axis along the Z-axis; this multi-axis motion mechanism supports multi-angle relative movement between the printhead and the insulating substrate.

[0037] In some embodiments of the present invention, the inner diameter of the cylindrical through hole should not be less than 400 μm, and the height (length) of the cylindrical through hole should not be greater than 3 times the inner diameter of the through hole. If the inner diameter of the cylindrical through hole is less than 400 μm, it is difficult to perform good spraying on the entire inner diameter of the through hole. If the height of the cylindrical through hole is greater than 3 times the inner diameter of the through hole, even if spraying is carried out on both sides of the through hole, it is difficult to cover the inner wall of the middle section of the through hole.

[0038] In some embodiments of the present invention, the through hole may include a tapered through hole. A tapered through hole refers to a through hole whose inner diameter varies proportionally.

[0039] When dealing with cylindrical through holes, the process of directly writing patterned insulating seed layers onto insulating substrates using aerosol jet printing technology according to the target pattern includes: placing the aerosol jet airflow on the side of the insulating substrate with the larger opening and directly facing the through hole to form an insulating seed layer.

[0040] In this embodiment, the motion axis system of the aerosol jet printing equipment does not need to be five-axis linked, and there are no strict requirements for the depth ratio of the through holes.

[0041] In some embodiments of the present invention, an insulating substrate with through holes is provided, which may include: providing an insulating substrate; and forming through holes in the insulating substrate by means of machinery or laser.

[0042] In some embodiments, the thickness of the insulating seed layer in the present invention can be 2 to 20 μm; the thickness of the metal plating layer in the present invention can be 1 to 20 μm.

[0043] The metal plating in the embodiments of the present invention may be one or more of copper, gold, silver, nickel, and zinc.

[0044] Another object of the present invention is to provide a conductive structure, which can be obtained by any of the above-described manufacturing methods.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for fabricating a conductive structure, characterized in that, include: An insulating substrate with through holes is provided, wherein neither the surface of the insulating substrate itself nor the inner wall of the through holes is plated. An insulating seed layer is formed by directly writing and printing an insulating plating ink onto an insulating substrate according to a target pattern using an aerosol jet printing process. The insulating seed layer is distributed on the surface of the insulating substrate and the inner wall of the through holes. A metal plating layer consistent with the target pattern is formed on the insulating seed layer by a chemical plating process.

2. The manufacturing method according to claim 1, characterized in that, The insulating plating ink comprises: copper oxide particles and adhesive resin; wherein the particle size of the copper oxide particles is between 1 nm and 1.5 μm; and the solid content of the copper oxide particles in the insulating plating ink is not less than 40%.

3. The manufacturing method according to claim 1, characterized in that, The through hole includes: a cylindrical through hole; The process of directly writing an insulating seed layer onto an insulating substrate using an aerosol jet printing process to form a patterned insulating seed layer according to a target pattern includes: The incident angle between the aerosol jet and the wall of the through hole is adjusted to an acute angle range, forming an insulating seed layer on the wall of the through hole.

4. The manufacturing method according to claim 3, characterized in that, The inner diameter of the cylindrical through hole is not less than 400 μm.

5. The manufacturing method according to claim 1, characterized in that, The through hole includes: a tapered through hole; The process of directly writing an insulating seed layer onto an insulating substrate using an aerosol jet printing process to form a patterned insulating seed layer according to a target pattern includes: An aerosol jet is positioned on the side of the insulating substrate with a larger opening, and is positioned directly opposite the through hole to form an insulating seed layer.

6. The manufacturing method according to claim 1, characterized in that, The insulating substrate has a planar structure or a three-dimensional structure.

7. The manufacturing method according to claim 1, characterized in that, The insulating substrate can be rigid or flexible.

8. The manufacturing method according to claim 1, characterized in that, The provision of an insulating substrate with through holes includes: Provide an insulating substrate as described above; The through holes are created on the insulating substrate by means of machinery or laser.

9. The manufacturing method according to claim 1, characterized in that, The thickness of the insulating seed layer is 2–20 μm.

10. A conductive structure, characterized in that, Obtained by the manufacturing method according to any one of claims 1-9.

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