CN114126248A

CN114126248A - Printed circuit board pad and circuit defect repairing method

Info

Publication number: CN114126248A
Application number: CN202210069547.1A
Authority: CN
Inventors: 钟刚
Original assignee: Shenzhen Yuanchi 3d Technology Co ltd
Current assignee: Shenzhen Yuanchi 3d Technology Co ltd
Priority date: 2022-01-21
Filing date: 2022-01-21
Publication date: 2022-03-01
Anticipated expiration: 2042-01-21
Also published as: CN114126248B

Abstract

The application belongs to the technical field of printed circuit board manufacturing, and relates to a method for repairing defects of a printed circuit board pad and a printed circuit board, which comprises the following steps: detecting a welding disc and a circuit defect part of the printed circuit board; etching the welding disc and the circuit defect part of the printed circuit board by adopting laser processing equipment; setting a first direct writing parameter of micro direct writing, and distributing the conductive electronic paste to the printed circuit board bonding pad and the circuit defect part etched by laser equipment according to the first direct writing parameter; and adopting a high-temperature annealing curing mode or a laser sintering curing mode to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit. The processing and repairing can be carried out at the defect position by the modes of micro-pen direct writing and laser sintering, so that the time and the cost for repairing the defect are saved; the direct writing parameters can be controlled to print the bonding pads and circuits with different thicknesses and sizes, so that the printing method is more accurate and convenient; and the mounting is integrated, so that the operation flow is reduced, and the production efficiency is improved.

Description

Printed circuit board pad and circuit defect repairing method

Technical Field

The application relates to the technical field of printed circuit board manufacturing, in particular to a method for repairing a printed circuit board pad and a circuit defect.

Background

With the rapid development of electronic and communication technologies, the demand for printed circuit boards is increasing, and the performance requirements for printed circuit boards are also increasing, so that the defect of any open circuit defect is not allowed to exist. However, there are often thousands of pads and a large number of conductive circuits on a printed circuit board, which may cause damages, peeling, falling off, etc. of the pads and circuits during production, transportation, and mounting of electrical components, thereby causing open circuit or failure of mounting application, and therefore only scrapping treatment can be performed; once the printed circuit board is mounted with the electrical component, the scrapping of the printed circuit board will bring high cost, and further, the economic benefit of enterprises is seriously affected.

The repair technology of the printed circuit board in the current market mainly comprises a screen printing technology, a chemical plating technology, an electroplating technology and the like, before repair, the printed circuit board needs to be subjected to pretreatment such as protection, masking and the like, and then exposure, development and the like, so that the obvious defects of multiple steps, long flow path and the like exist; and once the printed circuit board is pasted with the electric element, the repairing difficulty is greatly improved, and the methods of screen printing, chemical plating, electroplating and the like are difficult to be applied.

Disclosure of Invention

The embodiment of the application aims to provide a printed circuit board pad and a circuit defect repairing method, so as to solve the problems that before the defect repairing of the printed circuit board in the prior art, the printed circuit board needs to be subjected to pretreatment such as protection and masking, and then is subjected to exposure and development, and the obvious defects of multiple steps, long flow path and the like exist.

In order to solve the above technical problems, the present application provides a method for repairing a defect of a pad and a circuit of a printed circuit board, which adopts the following technical scheme, including the steps of:

detecting a welding disc and a circuit defect part of the printed circuit board;

etching the welding disc and the circuit defect part of the printed circuit board by adopting laser processing equipment;

setting a first direct writing parameter of micro direct writing, and distributing the conductive electronic paste to the printed circuit board bonding pad and the circuit defect part etched by laser equipment according to the first direct writing parameter;

and adopting a high-temperature annealing curing mode or a laser sintering curing mode to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit.

Further, the step of adopting a high-temperature annealing curing mode or a laser sintering curing mode to make the conductive electronic paste have conductivity and completing the repair of the defective bonding pad and the circuit further comprises:

and setting a second direct-writing parameter of the micro-pen direct writing, and directly writing the soldering paste on the surface of the repaired bonding pad according to the second direct-writing parameter.

Further, after the step of setting a second direct writing parameter of the micro-pen direct writing and directly writing the solder paste on the surface of the repaired pad according to the second direct writing parameter, the method further includes:

and (3) mounting the electrical element to be mounted on the soldering paste, and placing the electronic element and the printed circuit board together in a reflow soldering furnace for reflow soldering to finish mounting of the electrical element.

Further, the conductive electronic paste includes:

silver paste, silver palladium paste, gold paste, platinum paste and molybdenum tungsten paste or a combination of a plurality of silver paste, silver palladium paste, gold paste, platinum paste and molybdenum tungsten paste.

Further, the laser processing apparatus includes:

nanosecond laser processing equipment, picosecond laser processing equipment or femtosecond laser processing equipment.

Further, the first write-through parameter includes:

the micro pen has an inner diameter of 0.25-0.30 mm, a direct writing air pressure of 0.15-0.30 MPa, a direct writing speed of 5-10 mm/s and a lap joint distance of 0.06-0.12 mm.

Further, the second write-through parameters include:

the micro pen has an inner diameter of 0.20-0.25 mm, a direct writing air pressure of 0.10-0.20 MPa, a direct writing speed of 3-6 mm/s and a lapping interval of 0.05-0.10 mm.

Furthermore, the thickness of the soldering paste is 5-45 μm.

Further, the laser sintering is provided with laser sintering parameters, and the laser sintering parameters are as follows:

the laser power is 1.0W-1.5W, the laser scanning speed is 2 mm/s-8 mm/s, and the laser scanning interval is 0.02 mm-0.05 mm.

Further, the thickness of the conductive electronic paste is 5-45 μm.

The traditional methods for repairing the pad and the circuit of the printed circuit board, such as screen printing and electroplating, need to protect and mask the rest areas, and if a large number of electrical elements are already mounted on the printed circuit board, the mask difficulty can be greatly improved, so that the traditional method is difficult to adapt. Compared with the prior art, the application mainly has the following beneficial effects: the method can be used for conveniently processing specific defect positions by means of micro-pen direct writing and laser sintering or high-temperature annealing and curing, and repairing is directly carried out by means of micro-pen direct writing and laser sintering or high-temperature annealing and curing, so that the time and the cost for repairing the defects are saved; the bonding pad is repaired by a micro-pen direct writing method, and the bonding pads and circuits with different thicknesses and sizes can be printed by controlling direct writing parameters, so that the method is more accurate and convenient compared with a chemical plating and electroplating method; the repairing of the defective bonding pad and the circuit and the mounting of the electric element are integrated, so that the operation flow is reduced, and the production efficiency is improved.

Drawings

In order to more clearly illustrate the solution of the present application, the drawings needed for describing the embodiments of the present application will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and that other drawings can be obtained by those skilled in the art without inventive effort.

Fig. 1 is a flowchart of one embodiment of a printed wiring board pad, line defect repair method of the present application.

Detailed Description

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the above figures are intended to cover non-exclusive inclusions. The terms "first," "second," and the like in the description and claims of this application or in the above-described drawings are used for distinguishing between different objects and not for describing a particular order.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.

Example one

Fig. 1 is a flowchart of one embodiment of a printed wiring board pad, line defect repair method of the present application. As shown in FIG. 1, pads and circuit defects of a printed wiring board were detected by an optical magnifier on a printed wiring board having a length of 200mm, a width of 100mm, a thickness of 1mm, an epoxy resin base material, and a copper outer conductive layer.

Etching the defective part of the pad of the printed circuit board and the defective part of the position of the circuit by using nanosecond ultraviolet laser processing equipment to remove residual metal copper at the defective pad and the circuit, and roughening the surface of the epoxy resin base material to ensure that the repaired conductive layer has high bonding strength with the substrate so as to meet the practical requirement;

then selecting a micro-pen with the inner diameter of 0.25mm, the direct-writing air pressure of 0.15MPa, the direct-writing speed of 5mm/s and the lap joint distance of 0.06mm, and directly writing the conductive silver paste which can be solidified at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repairing is to recover the damaged or lost parts, wherein the repairing needs to be explained in the following that the original pattern size and position cannot be changed);

then, putting the printed circuit board to be repaired, on which the electronic paste is directly written, into an oven for high-temperature annealing and curing, wherein the curing temperature is 150 ℃, and the curing time is 30min, so that the conductive electronic paste has conductivity, and the repair of the defective bonding pad and the circuit can be completed;

then, a micro-pen with the inner diameter of 0.20mm, the direct-writing air pressure of 0.10MPa, the direct-writing speed of 3mm/s and the lap joint spacing of 0.05mm is selected in a micro-straight writing mode, and solder paste with the thickness of 5 microns is directly written on the surface of the repaired bonding pad; and (3) mounting the electrical element to be mounted on the soldering paste, and placing the electronic element and the printed circuit board together in a reflow soldering furnace for reflow soldering so as to finish the mounting of the subsequent electrical element.

Compared with the prior art, the application mainly has the following beneficial effects: the method can be used for conveniently processing at a specific defect position by means of micro-pen direct writing and high-temperature annealing and curing, and repairing is directly carried out by means of micro-pen direct writing and high-temperature annealing and curing, so that the time and the cost for repairing the defect are saved; the bonding pad is repaired by a micro-pen direct writing method, and the bonding pads and circuits with different thicknesses and sizes can be printed by controlling direct writing parameters, so that the method is more accurate and convenient compared with a chemical plating and electroplating method; the repairing of the defective bonding pad and the circuit and the mounting of the electric element are integrated, so that the operation flow is reduced, and the production efficiency is improved.

Example two

On a printed wiring board 200mm in length, 100mm in width, 1mm in thickness, an epoxy resin base material, and copper as an outer conductive layer, a defective portion of a pad of the printed wiring board was detected by an optical magnifier.

Etching the defective part of the pad of the printed circuit board and the defective part of the position of the circuit by using nanosecond ultraviolet laser processing equipment to remove residual metal copper at the defective pad and the circuit, and roughening the surface of the epoxy resin to ensure that the repaired conductive layer has high bonding strength with the substrate so as to meet the practical requirement;

then, adopting a laser sintering curing mode for the conductive silver paste to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit; wherein, laser sintering is equipped with the laser sintering parameter, and the laser sintering parameter is: the laser power is 1.0W, the laser scanning speed is 2mm/s, and the laser scanning interval is 0.02 mm;

then, a micro-pen with the inner diameter of 0.20mm, the direct-writing air pressure of 0.10MPa, the direct-writing speed of 3mm/s and the lap joint spacing of 0.05mm is selected in a micro-straight writing mode, and solder paste with the thickness of 5 microns is directly written on the surface of the repaired bonding pad; and (3) attaching the electrical component to be attached to the soldering paste, and placing the electronic component and the printed circuit board together in a reflow soldering furnace for reflow soldering so as to complete the attachment of the subsequent electrical component.

Compared with the prior art, the application mainly has the following beneficial effects: the special defect position can be conveniently processed by the mode of micro-pen direct writing and laser sintering, and the repair is directly carried out by the mode of micro-pen direct writing and laser sintering, so that the time and the cost for repairing the defect are saved; the bonding pad is repaired by a micro-pen direct writing method, and the bonding pads and circuits with different thicknesses and sizes can be printed by controlling direct writing parameters, so that the method is more accurate and convenient compared with a chemical plating and electroplating method; the repairing of the defective bonding pad and the circuit and the mounting of the electric element are integrated, so that the operation flow is reduced, and the production efficiency is improved.

EXAMPLE III

Nanosecond ultraviolet laser is used for etching the defective part of the bonding pad of the printed circuit board and the defective part of the circuit position so as to remove residual metal copper at the defective bonding pad and the circuit, and the surface of the epoxy resin base material is roughened, so that high bonding strength is formed between the repaired conductive layer and the substrate, and the practical requirement is met;

then selecting a micro-pen with the inner diameter of 0.30mm, the direct-writing air pressure of 0.30MPa, the direct-writing speed of 10mm/s and the lap joint distance of 0.12mm, and directly writing the conductive silver paste which can be solidified at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repairing is to recover the damaged or lost parts, wherein the repairing needs to be explained in the following that the original pattern size and position cannot be changed);

then, a micro-pen with the inner diameter of 0.25mm, the direct-writing air pressure of 0.20MPa, the direct-writing speed of 6mm/s and the lap joint spacing of 0.10mm is selected in a micro-straight writing mode, and the soldering paste with the thickness of 45 microns is directly written on the surface of the repaired bonding pad; and (3) attaching the electrical component to be attached to the soldering paste, and placing the electronic component and the printed circuit board together in a reflow soldering furnace for reflow soldering so as to complete the attachment of the subsequent electrical component.

Example four

next, adopting a laser sintering curing mode for the conductive silver paste to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit, wherein the laser sintering is provided with laser sintering parameters which are as follows: the laser power is 1.5W, the laser scanning speed is 8mm/s, and the laser scanning interval is 0.05 mm;

EXAMPLE five

then, selecting a micro-pen with the inner diameter of 0.275mm, the direct-writing air pressure of 0.225MPa, the direct-writing speed of 7.5 mm/s and the lapping interval of 0.09mm, and directly writing the conductive silver paste which can be cured at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repair is to recover the damaged or lost parts, wherein the repair needs to be explained in the following that the original pattern size and position cannot be changed);

then, a micro-pen with the inner diameter of 0.225mm, the direct-writing air pressure of 0.15MPa, the direct-writing speed of 4.5mm/s and the lapping interval of 0.075mm is selected in a micro-pen writing mode, and solder paste with the thickness of 25 microns is directly written on the surface of the repaired bonding pad; and (3) attaching the electrical component to be attached to the soldering paste, and placing the electronic component and the printed circuit board together in a reflow soldering furnace for reflow soldering so as to complete the attachment of the subsequent electrical component.

EXAMPLE six

next, adopting a laser sintering curing mode for the conductive silver paste to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit, wherein the laser sintering is provided with laser sintering parameters which are as follows: the laser power is 1.25W, the laser scanning speed is 5mm/s, and the laser scanning interval is 0.035 mm;

EXAMPLE seven

then selecting a micro-pen with the inner diameter of 0.26mm, the direct-writing air pressure of 0.16MPa, the direct-writing speed of 6mm/s and the lap joint distance of 0.07mm, and directly writing the conductive silver paste which can be solidified at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repairing is to recover the damaged or lost parts, wherein the repairing needs to be explained in the following that the original pattern size and position cannot be changed);

then, a micro-pen with the inner diameter of 0.21mm, the direct-writing air pressure of 0.11MPa, the direct-writing speed of 4mm/s and the lap joint spacing of 0.06mm is selected in a micro-straight writing mode, and solder paste with the thickness of 6 microns is directly written on the surface of the repaired bonding pad; and (3) attaching the electrical component to be attached to the soldering paste, and placing the electronic component and the printed circuit board together in a reflow soldering furnace for reflow soldering so as to complete the attachment of the subsequent electrical component.

Example eight

next, adopting a laser sintering curing mode for the conductive silver paste to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit, wherein the laser sintering is provided with laser sintering parameters which are as follows: the laser power is 1.1W, the laser scanning speed is 3mm/s, and the laser scanning interval is 0.03 mm;

Example nine

Etching the defective part of the pad of the printed circuit board and the defective part of the position of the circuit by using picosecond ultraviolet laser processing equipment to remove residual metallic copper at the defective pad and the circuit and roughen the surface of the epoxy resin base material so that high bonding strength exists between the repaired conductive layer and the substrate to meet the practical requirement;

Example ten

next, adopting a laser sintering curing mode for the conductive silver paste to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit, wherein the laser sintering is provided with laser sintering parameters which are as follows: the laser power is 1.0W, the laser scanning speed is 2mm/s, and the laser scanning interval is 0.02 mm;

EXAMPLE eleven

Etching the defective part of the pad of the printed circuit board and the defective part of the position of the circuit by using femtosecond ultraviolet laser processing equipment to remove residual metallic copper at the defective pad and the circuit and roughen the surface of the epoxy resin base material so that high bonding strength exists between the repaired conductive layer and the substrate to meet the practical requirement;

Example twelve

EXAMPLE thirteen

then selecting a micro-pen with the inner diameter of 0.25mm, the direct-writing air pressure of 0.15MPa, the direct-writing speed of 5mm/s and the lap joint distance of 0.06mm, and directly writing the conductive silver palladium slurry which can be solidified at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repairing is to recover the damaged or lost parts, wherein the repairing needs to be explained in the following that the original pattern size and position cannot be changed);

Example fourteen

then selecting a micro-pen with the inner diameter of 0.25mm, the direct-writing air pressure of 0.15MPa, the direct-writing speed of 5mm/s and the lap joint distance of 0.06mm, and directly writing the conductive gold paste which can be solidified at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repairing is to recover the damaged or lost parts, wherein the repairing needs to be explained in the following that the original pattern size and position cannot be changed);

and then, adopting a laser sintering curing mode for the conductive gold slurry to enable the conductive electronic slurry to have conductivity, and finishing the repair of the defective bonding pad and the circuit, wherein the laser sintering is provided with laser sintering parameters which are as follows: the laser power is 1.0W, the laser scanning speed is 2mm/s, and the laser scanning interval is 0.02 mm;

Example fifteen

then selecting a micro-pen with the inner diameter of 0.25mm, the direct-writing air pressure of 0.15MPa, the direct-writing speed of 5mm/s and the lap joint distance of 0.06mm, and directly writing conductive platinum slurry which can be solidified at a low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repairing is to recover the damaged or lost parts, wherein the repairing needs to be explained in the following that the original pattern size and position cannot be changed);

Example sixteen

then selecting a micro-pen with the inner diameter of 0.25mm, the direct-writing air pressure of 0.15MPa, the direct-writing speed of 5mm/s and the lap joint distance of 0.06mm, and directly writing the conductive molybdenum-tungsten slurry which can be solidified at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed pattern (the circuit board is provided with a circuit pattern, only some parts are damaged or lost, and the repairing is to recover the damaged or lost parts, wherein the repairing needs to be explained in the following that the original pattern size and position cannot be changed);

and then, adopting a laser sintering curing mode for the conductive molybdenum-tungsten slurry to enable the conductive electronic slurry to have conductivity, and completing the repair of the defective bonding pad and the circuit, wherein the laser sintering is provided with laser sintering parameters which are as follows: the laser power is 1.0W, the laser scanning speed is 2mm/s, and the laser scanning interval is 0.02 mm;

Example seventeen

then, selecting a micro-pen with the inner diameter of 0.25mm, the direct-writing air pressure of 0.15MPa, the direct-writing speed of 5mm/s and the lap joint distance of 0.06mm, and directly writing conductive slurry which can be solidified at low temperature at a defective bonding pad and a circuit by the micro-pen according to a pre-designed graph (the circuit board is provided with a circuit graph, only some parts are damaged or lost, and the repair is to recover the damaged or lost parts, wherein the repair can not change the original graph size and position), wherein the conductive slurry is the combination of silver slurry, silver palladium slurry, gold slurry, platinum slurry and molybdenum tungsten slurry;

then, putting the printed circuit board to be repaired, on which the electronic paste is directly written, into an oven for high-temperature annealing and curing, wherein the curing temperature is 150 ℃ and the curing time is 30min, so that the paste combination of the silver paste, the silver-palladium paste, the gold paste, the platinum paste and the molybdenum-tungsten paste has conductivity, and the repair of the defective bonding pad and the circuit can be completed;

EXAMPLE eighteen

and then, adopting a laser sintering curing mode for the slurry combination of the silver slurry, the silver-palladium slurry, the gold slurry, the platinum slurry and the molybdenum-tungsten slurry to enable the conductive electronic slurry to have conductivity, and completing the repair of the defective bonding pad and the circuit, wherein the laser sintering is provided with laser sintering parameters which are as follows: the laser power is 1.0W, the laser scanning speed is 2mm/s, and the laser scanning interval is 0.02 mm;

Example nineteen

Fig. 1 is a flowchart of an embodiment of a method for repairing a pad defect of a printed wiring board according to the present application. As shown in FIG. 1, a defective portion of a land of a printed wiring board was detected by an optical magnifier on a printed wiring board having a length of 200mm, a width of 100mm, a thickness of 1mm, an epoxy resin base material, and a copper outer conductive layer.

Example twenty

It is to be understood that the above-described embodiments are merely illustrative of some, but not restrictive, of the broad invention, and that the appended drawings illustrate preferred embodiments of the invention and do not limit the scope of the invention. This application is capable of embodiments in many different forms and is provided for the purpose of enabling a thorough understanding of the disclosure of the application. Although the present application has been described in detail with reference to the foregoing embodiments, it will be apparent to one skilled in the art that the present application may be practiced without modification or with equivalents of some of the features described in the foregoing embodiments. All equivalent structures made by using the contents of the specification and the drawings of the present application are directly or indirectly applied to other related technical fields and are within the protection scope of the present application.

Claims

1. A method for repairing the defects of a printed circuit board pad and a circuit is characterized by comprising the following steps:

s1, detecting the pad and circuit defect of the printed circuit board;

s2, etching the welding disc and the circuit defect part of the printed circuit board by adopting laser processing equipment;

s3, setting a first direct writing parameter of micro-pen direct writing, and distributing the conductive electronic paste to the printed circuit board pad and the circuit defect part etched by the laser processing equipment according to the first direct writing parameter;

and S4, adopting a high-temperature annealing curing mode or a laser sintering curing mode to enable the conductive electronic paste to have conductivity, and completing the repair of the defective bonding pad and the circuit.

2. The method for repairing the defect of the bonding pad and the circuit of the printed circuit board according to claim 1, wherein the step of completing the repair of the defect bonding pad and the circuit by adopting a high temperature annealing curing mode or a laser sintering curing mode to make the conductive electronic paste have conductivity further comprises:

3. The method for repairing the defect of the bonding pad and the circuit of the printed circuit board as claimed in claim 2, wherein after the step of setting a second direct writing parameter of the micro-pen direct writing and directly writing the solder paste on the surface of the repaired bonding pad according to the second direct writing parameter, the method further comprises the following steps:

4. The printed wiring board pad, line defect repair method of claim 1, wherein the conductive electronic paste comprises:

5. The printed wiring board pad, line defect repair method of claim 1, wherein the laser processing apparatus comprises:

6. The printed wiring board pad, line defect repair method of claim 1, wherein the first write parameter comprises:

7. The printed wiring board pad, line defect repair method of claim 3, wherein the second write-through parameters comprise:

the micro pen has an inner diameter of 0.20-0.25 mm, a direct writing air pressure of 0.10-0.20 MPa, a direct writing speed of 3-6 mm/s and a lap joint distance of 0.05-0.10 mm.

8. The method for repairing the defect of the printed circuit board pad and the circuit according to claim 3, wherein the thickness of the solder paste is 5 μm to 45 μm.

9. The printed circuit board pad and circuit defect repairing method according to any one of claims 1 to 8, wherein laser sintering parameters are set, and the laser sintering parameters are as follows:

10. The printed wiring board pad, line defect repairing method according to any one of claims 1 to 8, wherein the thickness of said conductive electronic paste is 5 μm to 45 μm.