A method for manufacturing an indium tin oxide printed circuit board

Abstract

The application discloses a manufacturing method of an indium tin oxide printed circuit board, which comprises the following steps: manufacturing a printed board and forming a first positioning hole; manufacturing an ITO film; processing an OPP film for bearing the ITO; according to the requirements of a drawing, using a laser to engrave a coil circuit of the ITO film and a second positioning hole; according to the requirements of the drawing design, milling the area of the ITO film coil on the OPP film except for at least three sun lines which are distributed at equal intervals, and the second positioning hole is located on the sun lines; according to the requirements of the drawing design, milling the area of the ITO film coil on the OPP film except for at least three sun lines and all the areas except for the sun lines; pressing: pre-laminating the ITO film, the PP film and the printed board, aligning the first and second positioning holes and riveting and positioning to press. The manufacturing method does not leave PP residual glue and OPP residual film in the central circular area of the ITO film and the coil of the effective area outside the sun lines, thereby guaranteeing the integrity of the signal transmission of the indium tin oxide printed circuit board coil.

Description

Technical Field

[0001] This invention relates to the field of circuit board manufacturing technology, and in particular to a method for manufacturing an indium tin oxide printed circuit board. Background Technology

[0002] In the electronics industry, printed circuit boards (PCBs) have become an indispensable component. Typically, the primary function of a PCB is to form the conductors that transmit information. In high-tech fields such as gas turbines, jet engines, and rocket engines, ITO (Indium Tin Oxide) printed circuit board technology is widely used, making it one of the main directions for research and development.

[0003] Indium-tin (ITO) film is a mixture of indium and tin, consisting of 90% In₂O₃ and 10% SnO₂. It is a transparent brown or yellowish-gray color and is commonly used in LEDs, flat panel displays, plasma displays, touch screens, antistatic coatings, transparent conductive coatings for EMI shielding, and solar cells. The main characteristic of ITO is its combination of electrical conductivity and optical transparency. ITO films are typically deposited onto a substrate surface using physical vapor deposition or sputtering deposition techniques.

[0004] Indium tin oxide (ITO) printed circuit boards are mainly made by laminating indium tin oxide film and high-frequency materials. By accurately calculating the ITO resistance value and designing the ITO pattern circuit in advance, while considering the resistance changes after being subjected to high temperature and high pressure during the process and the resistance changes after mixing with high-frequency materials, pre-compensation is performed to control the finished resistance value and coupling degree of ITO, and finally realize the fabrication of indium tin oxide circuit boards.

[0005] Currently, the lamination process for indium tin oxide (ITO) printed circuit boards presents the following technical challenges. Specifically, before lamination, a coil needs to be laser-etched onto the ITO film. Then, the ITO film coil is joined to the pre-fabricated high-frequency circuit board using a positioning and riveting technique. During this process, it is crucial to ensure that the coil on the ITO film and the coil on the printed circuit board are staggered and concentrically centered. That is, the coil on the ITO film must be centered within the gap between the coils on the high-frequency printed circuit board, and the offset between the coil on the ITO film and the adjacent coil on the high-frequency printed circuit board must not exceed 2 mils.

[0006] However, during the manufacturing process, since the area outside the ITO film coil cannot be pressed onto the high-frequency printed circuit board, the OPP transparent carrier film of the ITO film outside the coil needs to be milled. If the OPP film is completely milled, the ITO film cannot be positioned with the high-frequency printed circuit board. As a result, the ITO film coil has a large offset during the pressing process. If it cannot be guaranteed that the ITO film coil is centered with the coil on the high-frequency printed circuit board, and the offset cannot be guaranteed to be <+ / -2mil, the entire ITO printed circuit board will fail.

[0007] To overcome the above problems, the industry generally adopts the method of not milling the OPP film, that is, using the whole OPP film for positioning, pressing, and then milling off the useless OPP film. However, in practice, after pressing, excess OPP film will remain in the area outside the coil of the printed circuit board. If the OPP film is milled off by controlling the depth, there are several problems: (1) the dielectric layer is uneven, and the DK and DF deviations are large; (2) the bottom coil is easily damaged by milling, and the function fails; (3) the gold plating layer of the coil cannot be fully exposed, and the device cannot be soldered; (4) it has a great impact on the overall signal transmission and signal shielding effect. Summary of the Invention

[0008] In view of this, the present invention provides a method for manufacturing an indium tin oxide printed circuit board that can solve the above-mentioned technical problems.

[0009] A method for manufacturing an indium tin oxide printed circuit board includes the following steps:

[0010] STEP101: Printed Circuit Board Manufacturing: Material Cutting -- Drilling -- Shaping -- Outer Layer Circuit -- First Copper -- Outer Layer Circuit -- Second Copper -- Outer Layer Etching -- AOI -- Outer Layer Circuit -- Surface Treatment -- Outer Layer Etching -- Testing. The drilled holes include the first positioning holes set on the outer edge of the printed circuit board.

[0011] STEP 102: Fabrication of the ITO film:

[0012] STEP1021: Provide an OPP transparent film to be used as a carrier. Clean the surface of the OPP transparent film before sputtering deposition to ensure that there are no wrinkles or dust.

[0013] STEP1022: Preheat the magnetron sputtering machine for 1-2 hours;

[0014] STEP1023: Place the OPP film into the magnetron sputtering machine and sputter the entire ITO film, ensuring a thickness of 100+ / -10% nm and a sheet resistance of 100+ / -5% Ω.

[0015] STEP103: Processing OPP films for carrying ITO:

[0016] STEP1031: According to the drawing requirements, use laser to etch the ITO film coil circuit with an accuracy control of + / -5%, and etch the second positioning hole;

[0017] STEP1032: According to the design requirements of the drawings, mill the area on the OPP film other than the ITO film coil to form at least three sun rays, which are equally spaced at an angle, and the second positioning hole is located on the sun rays;

[0018] STEP1033: According to the design requirements of the drawings, mill out all areas on the OPP film except for the ITO film coils, except for at least three of the aforementioned sun rays;

[0019] STEP104: Pressing:

[0020] STEP1041: Provide at least one PP film, pre-stack the OPP film carrying ITO, the PP film and the printed circuit board, and align the first and second positioning holes and rivet them in place.

[0021] STEP1042: Pressing heating rate controlled at 2.0 + / - 0.5℃ / min, maximum pressure 360PSI, maximum material temperature 195℃, set to full pressure for 13-18min, and hold temperature and pressure for 40-60min to obtain indium tin oxide printed circuit boards.

[0022] Furthermore, in step STEP101, the outer layer circuit is a spiral coil.

[0023] Further, in step STEP101, the printed circuit board is made of F4BM300-1.6mmH / H microwave material.

[0024] Furthermore, in step STEP 1023, the resistance of the ITO film is 100Ω.

[0025] Furthermore, in step STEP1031, the coil etched on the ITO film is a helical coil, and the pitch of the helical coil remains consistent.

[0026] Furthermore, in step STEP 1032, the sun rays are six in number, and the angle between two adjacent sun rays is 60 degrees.

[0027] Furthermore, the width of the solar rays is 2 to 4 mm.

[0028] Furthermore, in step STEP 1033, the ITO film is formed into a ring by milling the OPP film.

[0029] Furthermore, in STEP 1041, when the ITO film and the printed circuit board are pre-stacked, the coil of the ITO film is located between the coils on the printed circuit board, and the coil of the ITO film and the coil on the printed circuit board are concentrically arranged.

[0030] Furthermore, in STEP1042, the OPP transparent film and PP film are thermally fused together using Lotte, and the sunlight is cut off after thermal fusion.

[0031] Compared with existing technologies, the method for manufacturing an indium tin oxide (ITO) printed circuit board of the present invention mills sun rays into the OPP film carrying the ITO film, and simultaneously positions the second positioning hole on the sun ray. Because milling the sun rays simultaneously removes the area of ​​the OPP film other than the ITO film coil, and also mills away the OPP film below the sun rays, the ITO film no longer contains any useless OPP film. During lamination and pre-stacking, the second positioning hole is first positioned with the first positioning hole on the printed circuit board, ensuring precise and fixed positioning during the thermal fusion of the OPP film and PP film, achieving the design requirement that the offset between the ITO film coil and the high-frequency printed circuit board coil is less than + / - 2 mil. After thermal fusion, multiple sun rays and the OPP film below them are directly cut. Due to the small size of the sun rays, cutting does not affect the shape of the effective area of ​​the ITO film coil, and also ensures that no residual PP adhesive or OPP film remains in the coil of the central circular area of ​​the ITO film and the effective area outside the sun rays, thus guaranteeing the integrity of the signal transmission of the indium tin oxide printed circuit board coil. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of the printed circuit board prepared in the method for manufacturing an indium tin oxide printed circuit board provided by the present invention.

[0033] Figure 2 This is a schematic diagram of the structure of the ITO film prepared in the method for manufacturing an indium tin oxide printed circuit board.

[0034] Figure 3 for Figure 2 A schematic diagram of the structure of an ITO film formed into a sun ray after milling.

[0035] Figure 4 This is a schematic diagram of the structure of the printed circuit board and the ITO film after lamination. Detailed Implementation

[0036] The following provides a more detailed description of specific embodiments of the present invention. It should be understood that the description of the embodiments of the present invention herein is not intended to limit the scope of protection of the present invention.

[0037] Please see Figures 1 to 4 The present invention provides a method for manufacturing an indium tin oxide printed circuit board, which includes the following steps:

[0038] STEP101: Printed Circuit Board 10: Material cutting -- Drilling -- Shaping -- Outer layer circuit -- First copper -- Outer layer circuit -- Second copper -- Outer layer etching -- AOI -- Outer layer circuit -- Surface treatment -- Outer layer etching -- Testing. The drilled holes include the first positioning hole 11 set on the outer frame of the printed circuit board.

[0039] STEP 102: Fabrication of ITO film 20:

[0040] STEP1021: Provide an OPP transparent film to be used as a carrier. Clean the surface of the OPP transparent film before sputtering deposition to ensure that there are no wrinkles or dust.

[0041] STEP1022: Preheat the magnetron sputtering machine for 1-2 hours;

[0042] STEP1023: Place the OPP film into the magnetron sputtering machine and sputter the entire ITO film, ensuring a thickness of 100+ / -10% nm and a sheet resistance of 100+ / -5% Ω.

[0043] STEP103: Processing OPP films for carrying ITO:

[0044] STEP1031: According to the drawing requirements, use laser to etch the ITO film coil circuit with an accuracy control of + / -5%, and etch the second positioning hole 21;

[0045] STEP1032: According to the design requirements of the drawings, the area on the OPP film other than the ITO film coil is milled to form at least three sun rays 22, which are equally spaced at an angle, and the second positioning hole 21 is located on the sun rays;

[0046] STEP1033: According to the design requirements of the drawings, mill out all areas on the OPP film except for the ITO film coils, except for at least three of the aforementioned sun rays 22;

[0047] STEP104: Pressing:

[0048] STEP1041: Provide at least one PP film, pre-stack the OPP film carrying ITO, the PP film and the printed circuit board, and align the first and second positioning holes 11 and 22 and rivet them for positioning.

[0049] STEP1042: The pressing and heating rate is controlled at 2.0 + / - 0.5℃ / min, the maximum pressure is 360 PSI, the maximum material temperature is 195℃, the full pressure is set for 13-18 minutes, and the heat and pressure are held for 40-60 minutes to obtain indium tin oxide printed circuit boards.

[0050] In step STEP 101, the printed circuit board can be a high-frequency circuit board, which can be made of F4BM300-1.6mmH / H microwave material. Simultaneously with drilling the holes in the printed circuit board, the first positioning hole should also be drilled. It is well known that each circuit board has multiple through-holes, which, after copper plating, are used to electrically connect circuits between different layers. The first positioning hole is drilled simultaneously with the through-holes, and both the first positioning hole and the through-holes are drilled according to the same drilling data. It is understood that the drilling data can be a CAD drawing or a Protel drawing designed by R&D personnel. The first positioning hole should be located on the outer edge of the printed circuit board to avoid interfering with the arrangement of other circuits on the printed circuit board. Figure 1 The diagram shown is a schematic representation of a printed circuit board provided in this embodiment. It is conceivable that this is merely an example used to illustrate the invention. The printed circuit board 10 has coils and a plurality of first positioning holes 11.

[0051] In step STEP 102, the fabrication of the ITO film 20 is an existing technology. However, when the ITO film 20 is used in circuit board fabrication, its precision, thickness, and resistance must be strictly guaranteed to meet the requirements of the circuit board.

[0052] In step STEP 103, each step should be performed according to the drawing requirements. The specifications, dimensions, and parameters of the drawing should correspond to the corresponding parameters for fabricating the printed circuit board. The position of the second positioning hole should correspond to the position of the first positioning hole. The helical coil laser-etched on the ITO film should be compatible with the parameters of the helical coil on the printed circuit board, such as the center position and pitch, so that when the ITO film and the printed circuit board are pressed together, the coil on the ITO film and the coil on the printed circuit board are offset from each other and concentrically centered. That is, the coil on the ITO film is centered in the gap between the coils on the high-frequency printed circuit board, and the offset between the coil on the ITO film and the coil on the adjacent high-frequency printed circuit board should not exceed 2 mil. Therefore, in STEP 101, the coil etched on the printed circuit board should also include a helical coil. To ensure the above-mentioned accuracy requirements for offset, the pitch of the helical coil should be consistent. Figure 2 As shown, it is a schematic diagram of the structure of the OPP film carrying ITO prepared in step STEP1031.

[0053] In step STEP101032, as follows Figure 3As shown, since three points define a plane, at least three sun rays should be provided. It should be noted that the term "sun ray" is merely a figurative description; because the coils on the ITO film are generally circular, and the sun ray extends from the edge of the ITO film like rays emitted by the sun, it is named a sun ray. In this embodiment, there are six sun rays, with an angle of 60 degrees between adjacent sun rays, ensuring even distribution. Each sun ray has a second positioning hole at its end. These second positioning holes are aligned with the first positioning holes and secured with rivets, thus positioning the ITO film 10 and the printed circuit board 20 for subsequent thermal bonding processes. The length of the sun ray should extend beyond the edge of the printed circuit board. Since the sun ray is only used for positioning, its width is 2 to 4 mm.

[0054] During the formation of the sun rays, all the useless OPP film will be milled off. Of course, the OPP film under the sun rays may not be milled off, as its small size means that there will be no residue that affects the overall performance of the circuit board when it is broken or cut.

[0055] After the OPP film is milled, the ITO film 20 becomes annular. At this time, the ITO film 20 is basically the same as the shape of the actual product, except that it has sun rays.

[0056] Next, lamination can be performed, that is, laminating the ITO film 20 with sunlight rays to the printed circuit board 10. For example... Figure 4 During the pressing process, by aligning the first and second positioning holes 11 and 21, the coil of the ITO film 20 is positioned between the coils on the printed circuit board 10. The coil of the ITO film 20 is concentrically arranged with the coil on the printed circuit board 20, thereby completing the positioning of the ITO film 20 and the printed circuit board 10.

[0057] After positioning is complete, thermal fusion can be performed, that is, the OPP film and PP film on the ITO film 20 are thermally fused together. During thermal fusion, a heating element is used for heating. It is conceivable that the size and shape of the heating element should be the same as the size and shape of the ITO film 20, so as to facilitate thermal fusion only of the OPP film and the corresponding PP film on the ITO film 20.

[0058] After thermal fusion, the solar panels are cut to complete the fabrication of the ITO circuit board. Cutting the solar panels can be done using a CNC machine tool, or for applications with lower precision requirements, they can be broken manually.

[0059] Compared with existing technologies, the method for manufacturing an indium tin oxide (ITO) printed circuit board of the present invention mills sun rays into the OPP film carrying the ITO film, and simultaneously positions the second positioning hole on the sun ray. Because milling the sun rays simultaneously removes the area of ​​the OPP film other than the ITO film coil, and also removes the OPP film below the sun rays, the ITO film no longer contains any useless OPP film. During lamination and pre-stacking, the second positioning hole is first aligned with the first positioning hole on the printed circuit board, ensuring precise and stable positioning during the thermal fusion of the OPP film and PP film, achieving the design requirement that the offset between the ITO film coil and the high-frequency printed circuit board coil is less than + / - 2 mil. After thermal fusion, multiple sun rays and the OPP film below them are directly cut. Due to the small size of the sun rays, cutting does not affect the shape of the effective area of ​​the ITO film coil, while also ensuring that no residual PP adhesive or OPP film remains in the coil of the central circular area of ​​the ITO film and the effective area outside the sun rays, thus guaranteeing the integrity of the signal transmission of the indium tin oxide printed circuit board coil.

[0060] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions or improvements within the spirit of the present invention are covered within the scope of the claims of the present invention.

Claims

1. A method for manufacturing an indium tin oxide printed circuit board, comprising the following steps: STEP101: Printed Circuit Board Manufacturing: Material Cutting -- Drilling -- Shaping -- Outer Layer Circuit -- First Copper -- Outer Layer Circuit -- Second Copper -- Outer Layer Etching -- AOI -- Outer Layer Circuit -- Surface Treatment -- Outer Layer Etching -- Testing. The drilled holes include the first positioning holes set on the outer edge of the printed circuit board. STEP 102: Fabrication of the ITO film: STEP1021: Provide an OPP transparent film to be used as a carrier. Clean the surface of the OPP transparent film before sputtering deposition to ensure that there are no wrinkles or dust. STEP1022: Preheat the magnetron sputtering machine for 1-2 hours; STEP1023: Place the OPP film into the magnetron sputtering machine and sputter the entire ITO film, ensuring a thickness of 100+ / -10% nm and a sheet resistance of 100+ / -5% Ω. STEP103: Processing OPP films for carrying ITO: STEP1031: According to the drawing requirements, use laser to etch the ITO film coil circuit with an accuracy control of + / -5%, and etch the second positioning hole; STEP1032: According to the design requirements of the drawings, mill the area on the OPP film other than the ITO film coil to form at least three sun rays, which are equally spaced at an angle, and the second positioning hole is located on the sun rays; STEP1033: According to the design requirements of the drawings, mill out all areas on the OPP film except for the ITO film coils, except for at least three of the aforementioned sun rays; STEP104: Pressing: STEP1041: Provide at least one PP film, pre-stack the OPP film carrying ITO, the PP film and the printed circuit board, and align the first and second positioning holes and rivet them in place. STEP1042: Pressing heating rate controlled at 2.0 + / - 0.5℃ / min, maximum pressure 360PSI, maximum material temperature 195℃, set to full pressure for 13-18min, and hold temperature and pressure for 40-60min to obtain indium tin oxide printed circuit boards.

2. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In step STEP101, the outer layer circuit is a spiral coil.

3. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In step STEP101, the printed circuit board is made of F4BM300-1.6mmH / H microwave material.

4. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In step STEP 1033, while milling the area outside the ITO film coil on the OPP film, a central circular hole is also milled on the ITO film.

5. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In step STEP1031, the coil etched on the ITO film is a helical coil, and the pitch of the helical coil remains consistent.

6. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In step STEP1032, the sun rays are six in number, and the angle between any two adjacent sun rays is 60 degrees.

7. The method for manufacturing an indium tin oxide printed circuit board as described in claim 6, characterized in that: The width of the sun rays is 2 to 4 mm.

8. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In step STEP 1033, the ITO film is formed into a ring by milling the OPP film.

9. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In STEP1041, when the ITO film and the printed circuit board are pre-stacked, the coil of the ITO film is located between the coils on the printed circuit board, and the coil of the ITO film and the coil on the printed circuit board are concentrically arranged.

10. The method for manufacturing an indium tin oxide printed circuit board as described in claim 1, characterized in that: In STEP1042, the OPP transparent film and PP film are heat-fused together using a soldering iron, and the sun rays are cut off after the heat fusion.

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