A circuit processing method based on nano-metal pulse electrosintering

Abstract

The present application provides a circuit processing method based on nano-metal pulse electrosintering, wherein the method comprises the following steps: obtaining a position to be processed on a circuit board; placing a nano-sintering material at the position to be processed, and dripping a pulse electroplating solution on the nano-sintering material; arranging a metal probe on the pulse electroplating solution, connecting a pulse voltage to the metal probe and the circuit board, heating and surface electroplating the nano-sintering material, and sintering the nano-sintering material using a laser; cleaning the circuit board, and surface treating the circuit board; The present application embodiment provides a circuit processing method based on nano-metal pulse electrosintering, thereby greatly improving the sintering efficiency of nano-materials, effectively improving the forming or repair efficiency of the circuit, and effectively improving the forming or repair quality of the circuit.

Description

Technical Field

[0001] The present application relates to the technical field of integrated circuits, and in particular to a circuit processing method based on nano-metal pulse electrosintering. Background Art

[0002] Fine circuit boards are the support bodies of electronic components and the carriers of electrical connections. As electronic products develop towards miniaturization and digitalization, printed circuit boards are also developing towards high density, high precision, fine aperture, fine wire, fine pitch, high reliability, multi-layer, high-speed transmission, light weight, and thinness, which puts higher requirements on the forming and repair of fine circuits.

[0003] In the prior art, fine circuit boards use nano-metal materials in combination with laser sintering to form metal circuits. This method is suitable for the forming and repair of fine circuit boards and has the characteristics of high precision. However, this method has the problem of low efficiency and requires the laser to focus at a specific position for heating and sintering. Especially when used for circuit repair, low circuit repair efficiency means that it affects the time it takes for the circuit board to be put back into use.

[0004] There is currently no effective technical solution to the above problems. Summary of the invention

[0005] The purpose of the embodiments of the present application is to provide a circuit processing method based on nano-metal pulse electrosintering, so as to improve the sintering efficiency of nano-materials during circuit forming or repairing, thereby reducing the time required for circuit forming or repairing.

[0006] The embodiment of the present application provides a circuit processing method based on nano-metal pulse electrosintering, which is used to repair or shape a position to be processed on a circuit board. The method comprises the following steps:

[0007] S101, obtaining the position to be processed on the circuit board;

[0008] S102, placing a nano-sintered material at the position to be processed, and dripping a pulse plating solution on the nano-sintered material;

[0009] S103, placing a metal probe on the pulse electroplating solution, connecting a pulse voltage to the metal probe and the circuit board, heating and surface electroplating the nano-sintered material, and sintering the nano-sintered material using a laser;

[0010] S104, cleaning the circuit board and performing surface treatment on the circuit board.

[0011] The embodiment of the present application provides a circuit processing method based on nano-metal pulse electrosintering. The method places nano-sintered material at the position to be processed and then drips a pulse electroplating solution. The pulse voltage is used to quickly assist in heating the nano-sintered material through the pulse electroplating solution, which is beneficial to the laser sintering of the nano-sintered material, thereby greatly improving the efficiency of circuit processing.

[0012] In the circuit processing method based on nano-metal pulse electrosintering, the metal probe is one or a pair of metal probes made of different metal materials.

[0013] The circuit processing method based on nano-metal pulse electrosintering, wherein, in step S102, the pulse electroplating solution covers the position to be processed and has a spherical convex surface.

[0014] In the circuit processing method based on nano-metal pulse electrosintering, the circuit board is placed in an easily ionized gas atmosphere.

[0015] In the circuit processing method based on nano-metal pulse electrosintering, in step S103, an ultrasonic transmitter may be used to apply positive pressure ultrasonic waves to assist laser sintering.

[0016] The circuit processing method based on nano-metal pulse electrosintering, wherein step S104 includes sub-steps:

[0017] S1041, using a wet method to clean the circuit board to remove residual nano-sintered material;

[0018] S1042, passivating the cleaned circuit board.

[0019] In the circuit processing method based on nano-metal pulse electrosintering, in step S103, a power plate for changing the concentration of the cation region in the pulse electroplating solution can be placed under the circuit board.

[0020] In the circuit processing method based on nano-metal pulse electrosintering, the pulse voltage is a DC pulse voltage or a pulsating DC voltage obtained by rectifying an AC voltage.

[0021] In the circuit processing method based on nano-metal pulse electrosintering, in step S101, the position to be processed is a short circuit defect position or a position to be formed.

[0022] As can be seen from the above, the circuit processing method based on nano-metal pulse electrosintering provided in the embodiment of the present application, by placing nano-sintering material and then dripping pulse electroplating solution, using pulse voltage to quickly assist in heating the nano-sintering material through the pulse electroplating solution, is beneficial to the laser sintering treatment of the nano-sintering material, thereby greatly improving the sintering efficiency of the nano-material and effectively improving the forming or repair efficiency of the circuit; in addition, the pulse electroplating solution is electroplated by pulse voltage, so that the metal cations of the pulse electroplating solution are reduced to metals attached to the nano-sintering material, making the nano-sintering material more continuous and uniform, thereby improving the forming or repair quality of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A flow chart of a circuit processing method based on nanometal pulse electrosintering provided in an embodiment of the present application.

[0024] Figure 2-6 A detailed schematic diagram of a circuit processing method based on nanometal pulse electrosintering provided in an embodiment of the present application.

[0025] Figure numerals: 1. Circuit board; 2. Location to be processed; 3. Nano-sintered material; 4. Pulse plating solution; 5. Metal probe; 6. Laser probe. DETAILED DESCRIPTION

[0026] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application claimed for protection, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application.

[0027] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0028] First, please refer to Figure 1-6 , Figure 1-6 A circuit processing method based on nano-metal pulse electrosintering in some embodiments of the present application is used to repair or shape a position to be processed on a circuit board, and the method includes the following steps:

[0029] S101, obtaining a position 2 to be processed on a circuit board 1;

[0030] Specifically, the position 2 to be processed on the circuit board 1 can be obtained by means of electric pen detection or automatic optical detection technology. In the embodiment of the present application, automatic optical detection technology is preferably used to compare the circuit board 1 to be processed with the standard circuit board 1 to quickly and accurately obtain the position 2 to be processed on the circuit board 1 that needs to be processed.

[0031] More specifically, after obtaining the position 2 to be processed, the position 2 to be processed can be marked on the circuit board 1 or recorded through a computer program, which is conducive to the subsequent precise positioning of the position 2 to be processed for processing.

[0032] S102, placing a nano-sintered material 3 at the position to be processed 2, and dripping a pulse plating solution 4 on the nano-sintered material 3;

[0033] Specifically, the nano-sintered material 3 inserted into the position to be processed 2 should cover the entire position to be processed 2. If the position to be processed 2 is a straight line area with a length of 30 um, the nano-sintered material 3 should be covered along the straight line area so that the nano-sintered material 3 connects the front and rear ends of the area, thereby ensuring that the nano-sintered material 3 can continue to the position to be processed after sintering to achieve circuit repair or forming; in addition, the dripped pulse plating solution 4 should also cover the entire nano-sintered material 3 to ensure that it can effectively provide assistance to the nano-sintered material 3 and promote the nano-sintered material 3 to complete the circuit processing.

[0034] S103, placing a metal probe 5 on the pulse electroplating solution 4, connecting a pulse voltage to the metal probe 5 and the circuit board 1, heating and surface electroplating the nano-sintered material 3, and sintering the nano-sintered material 3 using a laser;

[0035] Specifically, when the metal probe 5 and the circuit board 1 are connected to a pulse voltage, the metal probe 5, the pulse electroplating solution 4, the nano-sintered material 3, and the circuit board 1 form a pulse circuit, in which a pulse current is generated, which quickly evaporates the pulse electroplating solution 4 to generate a high temperature, so that the nano-sintered material 3 quickly heats up and softens. At the same time, during the evaporation of the electroplating solution, the cations in the solute in the pulse electroplating solution 4 are reduced to metals and attached to the surface of the nano-sintered material 3, which can fill the gaps and uneven parts on the surface of the nano-sintered material 3, so that the shape of the nano-sintered material 3 is smoother and more uniform; the laser probe 6 is used to generate a laser to heat and sinter the heated nano-sintered material 3. Since a pulse voltage is used to heat the nano-sintered material 3, the time required for laser irradiation can be effectively reduced, and the time used for sintering can be greatly reduced, thereby improving the sintering efficiency of the nano-sintered material 3; after sintering, the nano-sintered material 3 in the original position 2 to be processed is sintered to form a metal line connected to the front and rear ends of the position 2 to be processed, thereby realizing the line connection of the position 2 to be processed.

[0036] S104 , cleaning the circuit board 1 , and performing surface treatment on the circuit board 1 .

[0037] Specifically, cleaning the circuit board 1 mainly involves removing excess nano-sintered material 3 , and surface treatment mainly involves insulation treatment to protect the circuit board 1 .

[0038] The embodiment of the present application provides a circuit processing method based on nano-metal pulse electrosintering. The method places a nano-sintered material 3 at a position to be processed 2 and then drips a pulse electroplating solution 4. A pulse voltage is used to rapidly assist in heating the nano-sintered material 3 through the pulse electroplating solution 4, which is beneficial to the laser sintering of the nano-sintered material 3, thereby greatly improving the efficiency of circuit processing. In addition, the pulse electroplating solution 4 is electroplated by a pulse voltage, so that the metal cations of the pulse electroplating solution 4 are reduced to metals and attached to the nano-sintered material 3, making the nano-sintered material 3 more continuous and uniform, thereby avoiding the problem of uneven filling or gaps of the nano-sintered material 3 in the position to be processed 2, resulting in unsatisfactory circuit connection effect or circuit connection failure.

[0039] In some preferred embodiments, in step S101, the position 2 to be processed is a circuit breaking defect position or a position to be formed; wherein the circuit breaking defect position is the position where the circuit breaking is caused by a problem or an accident on the original circuit board 1, and the position to be formed refers to the position on the unwired circuit board 1 where a metal circuit is required to be formed to realize the device.

[0040] The difference between the processing method of the position to be formed and the processing method of the short-circuit defect position is that in step S101, the position to be formed or the short-circuit defect position is directly obtained, and the processing methods in the remaining steps are the same. Therefore, the processing method of the embodiment of the present application is further explained below using the short-circuit defect position as an example.

[0041] In some preferred embodiments, laser irradiation can be performed after the pulse voltage is turned off, so that the pulse electroplating solution 4 on the surface of the nano-sintered material 3 is evaporated and then laser sintering is performed to ensure that the line repair process is carried out in an orderly manner; pulse voltage can also be turned on and laser irradiation can be performed at the same time, and the nano-sintered material 3 can be heated and heated by pulse voltage and laser irradiation at the same time, which can effectively reduce heat loss and improve sintering efficiency; laser irradiation can also be performed during the pulse voltage power-on process, effectively connecting the two heating processes to ensure that the sintering process is smooth.

[0042] In some preferred embodiments, the pulse voltage is a high-frequency pulse voltage, so that the pulse plating solution 4 can be evaporated quickly and the temperature of the nano-sintered material 3 can be assisted to rise.

[0043] In some preferred embodiments, the nano-sintering material 3 is nano-copper powder or nano-copper paste, and the pulse electroplating solution 4 is a copper sulfate solution; wherein copper is a commonly used circuit material with high conductivity and low cost, and therefore nano-material copper powder or copper paste is used as the nano-sintering material 3, which is conducive to laser rapid sintering and forming to produce metallurgical bonding to obtain a metal circuit for repairing the broken circuit position; similarly, the use of copper sulfate solution can electroplating and restore copper consistent with the circuit material, thereby ensuring the consistency of the repair circuit material.

[0044] In this embodiment, the copper sulfate solution is weakly acidic, which is conducive to the pulse voltage reducing the copper ions in the copper sulfate solution into copper and attaching them to the nano-sintered material 3.

[0045] In other embodiments, the pulse plating solution 4 may also be neutral or weakly alkaline. In this case, the pulse plating solution 4 only generates high temperature through pulse current to assist the nano-sintered material 3 to increase in temperature.

[0046] In some preferred embodiments, the nano-sintered material 3 is placed in the processing position 2 by brushing, so that the nano-sintered material 3 has a relatively flat upper surface, thereby improving the uniform height of the circuit formed after the nano-sintered material 3 is sintered. The laser sintering process is to displace along the repair circuit, and the optical path displacement process has a uniform width, so that a metal circuit with a uniform cross-section can be obtained, ensuring that the circuit after the broken circuit position is repaired has a relatively uniform cross-sectional area, effectively preventing the repaired circuit from being disconnected again to form a broken circuit.

[0047] In some preferred embodiments, when the nano-sintered material 3 uses a nano-copper paste, when preparing a paste containing nano-metal particles, the nano-metal particles can be added to an organic alcohol reagent, and then rosin and flux are added to form a paste, which is beneficial to improving the sintering efficiency of the metal circuit; in addition, in step S103, when a high-frequency pulse voltage is passed, the local temperature of the nano-sintered material 3 paste rises more significantly, which is beneficial to the metallurgical bonding of the nano-material and can further improve the sintering efficiency.

[0048] If the pulse plating solution 4 between the metal probe 5 and the nano-sintered material 3 evaporates a certain amount, the current cannot pass through the metal probe 5 and the nano-sintered material 3, which will cause the pulse plating solution 4 to remain and affect the laser heating sintering. Therefore, in some preferred embodiments, in order to ensure that the pulse plating solution 4 can be completely evaporated, the tip of the metal probe 5 contacts the top surface of the nano-sintered material 3 to ensure that the pulse voltage connected to the metal probe 5 can continue until the pulse plating solution 4 is evaporated.

[0049] In some preferred embodiments, the metal probe 5 is one or a pair of metal probes 5 made of different metal materials.

[0050] Specifically, when there is only one metal probe 5, the portion where the nano-sintered material 3 is connected between the metal probe 5 and the circuit board pulse voltage will generate a local temperature rise, which can assist the laser in sintering the material; for example Figure 5 In the circuit board 1 shown in the figure, if the left end of the circuit board 1 and the metal probe 5 are connected to a pulse voltage, the nano-sintered material 3 located on the left side of the metal probe 5 can quickly heat up. Therefore, the setting position of the metal probe 5 can be adjusted according to actual repair needs, and the adjustment of the heating position can be achieved, so that the repair method of the present application is suitable for different repair needs.

[0051] Specifically, when there are two metal probes 5, and the two metal probes 5 are made of the same metal material, when the pair of metal probes 5 with dissimilar charges approach the position to be processed 2 on the circuit board 1, a local strong electric field will be formed due to the characteristics of dissimilar metals, causing gas ionization, thereby causing the air near the tip of the metal probe 5 to heat up, which is beneficial to the heating of the nano sintering material 3, thereby assisting the laser sintering.

[0052] In some preferred embodiments, in step S102, the pulse plating solution 4 covers the position to be processed 2 and has a spherical convex surface; specifically, the pulse plating solution 4 uses liquid tension to generate a spherical convex surface, which is conducive to its complete coverage of the nano-sintered material 3 and the position to be processed 2, and is conducive to the metal probe 5 being inserted into the pulse plating solution 4. By using the pulse plating solution covering the entire position to be processed 2, it can be ensured that the pulse voltage can be smoothly connected to the power-on, thereby avoiding power-on failure caused by tiny defects in the nano-sintered material 3.

[0053] In some preferred embodiments, the pulse plating solution 4 is dripped onto the position to be processed 2 using a drip nozzle to ensure that the dripping amount of the solution can effectively cover the position to be processed 2 without excessive overflow.

[0054] In some preferred embodiments, the circuit board 1 is placed in an easily ionized gas atmosphere; after a high-frequency pulse voltage is applied, the gas can be ionized, and the ionized gas is used for conduction, so that the gas near the tip of the metal probe 5 generates a high temperature, which is beneficial to the laser sintering of the nano sintered material 3, thereby improving the sintering efficiency.

[0055] In some preferred embodiments, the gas of the easily ionizable gas atmosphere includes hydrogen, helium, xenon, etc. In this embodiment, it is one or more of them.

[0056] In some preferred embodiments, in step S103, an ultrasonic transmitter may be used to apply positive pressure ultrasonic waves to assist laser sintering.

[0057] Specifically, the positive pressure is applied by the ultrasonic transmitter to generate a small amplitude oscillating pressure, which has a hammering effect on the nano sintered material 3, thereby improving the sintering effect and making the material more stable after sintering.

[0058] In some preferred embodiments, step S104 includes sub-steps:

[0059] S1041, using a wet method to clean the circuit board 1 to remove residual nano-sintered material 3;

[0060] Specifically, the circuit board 1 is cleaned with ethanol under ultrasonic conditions, which can effectively remove the residual nano-sintered material 3 on the circuit board 1, ensure the circuit board 1 is clean, and avoid the nano-sintered material 3 adhering to the circuit to cause short circuit or other problems.

[0061] S1042, performing passivation treatment on the cleaned circuit board 1.

[0062] Specifically, after the circuit board 1 is passivated, the circuit on the circuit board 1 can have a dense passivation film, which can completely separate the metal from the corrosive medium, prevent the metal from directly contacting the corrosive medium, and achieve the effect of preventing corrosion.

[0063] In some preferred embodiments, in step S103 , a power plate for changing the concentration of the cation region in the pulse plating solution 4 may be placed under the circuit board 1 .

[0064] Specifically, the energized plate is provided so that the cations are enriched near the nano-sintered material 3, which is beneficial for the cations to be reduced to metals and attached to the nano-sintered material 3, that is, the concentration of metal ions in the electroplating area near the nano-sintered material 3 is increased, thereby improving the electroplating efficiency.

[0065] In some preferred embodiments, the pulse voltage is a DC pulse voltage or a pulsating DC voltage obtained by rectifying an AC voltage.

[0066] Specifically, the pulse voltage is a high-frequency pulse voltage, which can quickly heat up the nano-sintered material 3; the pulse voltage is preferably a pulsating DC voltage obtained by rectifying an AC voltage.

[0067] In other embodiments, alternating current with different positive and negative voltages can be used as pulse voltage to implement electroplating heating treatment, which is beneficial to the stability of the circuit after sintering.

[0068] Embodiment 1

[0069] Take a circuit board with a circuit break problem, use automatic optical inspection technology, namely AOI technology, to determine the position of the circuit break on the circuit board, brush a layer of nano copper powder on the circuit break position to be repaired, and dot 0.5 ml of copper sulfate solution with a concentration of 1 mol / L, so that the copper sulfate solution covers the nano copper powder on the circuit break position, set a metal probe to be inserted from above the copper sulfate solution, and pass a 5V, 50Hz square wave pulse voltage through one end of the circuit board to be repaired and the metal probe, so that the pulse copper sulfate solution and the nano copper powder are quickly heated up; move a laser probe with a diameter of 20μm to a height of 100μm from the area to be repaired, emit a laser for sintering, and sinter the nano copper powder into a copper circuit after the laser irradiates along the area to be repaired; use ethanol to clean the circuit board under ultrasonic conditions to remove residual nano copper powder particles, and finally passivate the cleaned circuit board and print carbon ink.

[0070] Embodiment 2

[0071] Take a circuit board with a circuit break problem, use automatic optical inspection technology, namely AOI technology, to determine the position of the circuit break on the circuit board, brush a layer of nano copper paste on the circuit break position to be repaired, and dot 0.3 ml of copper sulfate solution with a concentration of 1.5 mol / L, so that the copper sulfate solution covers the nano copper paste on the circuit break position, set a metal probe to insert from above the copper sulfate solution and touch the nano copper paste, pass a 10V, 50Hz sharp pulse voltage on the circuit board to be repaired, so that the pulse copper sulfate solution and nano copper powder heat up rapidly; move a laser probe with a diameter of 20μm to a height of 100μm from the area to be repaired, emit a laser for sintering, and sinter the nano copper paste into a copper circuit after the laser irradiates along the area to be repaired; use ethanol to clean the circuit board under ultrasonic conditions to remove residual nano copper powder particles, and finally passivate the cleaned circuit board and print carbon ink.

[0072] Embodiment 3

[0073] Take a circuit board to be formed, use automatic optical inspection technology (AOI) technology to determine all the positions to be connected and formed on the circuit board, brush a layer of nano copper paste on all the positions to be connected and formed, and dot 0.3 ml of copper sulfate solution with a concentration of 1.5 mol / L, so that the copper sulfate solution covers the nano copper paste on the positions to be connected and formed, set a metal probe to be inserted from above the copper sulfate solution and touch the nano copper paste, pass a 10V, 50Hz sharp pulse voltage on the circuit board to be formed, so that the pulse copper sulfate solution and nano copper powder are quickly heated; move a laser probe with a diameter of 20μm to a height of 100μm from the area to be formed, emit laser for sintering, and sinter the nano copper paste into a copper circuit after the laser is irradiated along the area to be formed; use ethanol to clean the circuit board under ultrasonic conditions to remove residual nano copper powder particles, and finally passivate the cleaned circuit board and print carbon ink.

[0074] As can be seen from the above, the circuit processing method based on nano-metal pulse electrosintering provided in the embodiment of the present application, by placing nano-sintering material and then dripping pulse electroplating solution, using pulse voltage to quickly assist in heating the nano-sintering material through the pulse electroplating solution, is beneficial to the laser sintering treatment of the nano-sintering material, thereby greatly improving the sintering efficiency of the nano-material and effectively improving the forming or repair efficiency of the circuit; in addition, the pulse electroplating solution is electroplated by pulse voltage, so that the metal cations of the pulse electroplating solution are reduced to metals attached to the nano-sintering material, making the nano-sintering material more continuous and uniform, thereby improving the forming or repair quality of the circuit.

[0075] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A circuit processing method based on nano-metal pulse electrosintering, used for repairing or shaping the position to be processed on the circuit board, characterized in that: The method comprises the following steps: S101, obtaining the position to be processed on the circuit board; S102, placing a nano-sintered material at the position to be processed, and dripping a pulse plating solution on the nano-sintered material; S103, placing a metal probe on the pulse electroplating solution, connecting a pulse voltage to the metal probe and the circuit board, heating and surface electroplating the nano-sintered material, sintering the nano-sintered material using a laser, and applying positive pressure ultrasonic waves to assist laser sintering using an ultrasonic transmitter; S104, cleaning the circuit board and performing surface treatment on the circuit board; In step S103, a power plate for changing the concentration of the cation region in the pulse plating solution is placed under the circuit board.

2. The circuit processing method based on nanometal pulse electrosintering according to claim 1, characterized in that: The nano sintering material is nano copper powder or nano copper paste, and the pulse electroplating solution is copper sulfate solution.

3. The circuit processing method based on nano-metal pulse electrosintering according to claim 1, characterized in that: The metal probe is one or a pair of metal probes made of different metal materials.

4. The circuit processing method based on nanometal pulse electrosintering according to claim 1, characterized in that: In step S102, the pulse plating solution covers the position to be processed and has a spherical convex surface.

5. The circuit processing method based on nano-metal pulse electrosintering according to claim 1, characterized in that: The circuit board is placed in an easily ionized gas atmosphere.

6. The circuit processing method based on nano-metal pulse electrosintering according to claim 1, characterized in that: Step S5 includes sub-steps: S1041, using a wet method to clean the circuit board to remove residual nano-sintered material; S1042, passivating the cleaned circuit board.

7. The circuit processing method based on nano-metal pulse electrosintering according to claim 1, characterized in that: The pulse voltage is a DC pulse voltage or a pulsating DC voltage obtained by rectifying an AC voltage.

8. The circuit processing method based on nanometal pulse electrosintering according to any one of claims 1 to 7, characterized in that: In step S101, the position to be processed is a disconnection defect position or a position to be formed.

Images