CN112533379A - Manufacturing method of PCB resin plug hole - Google Patents

Abstract

The invention discloses a method for manufacturing a PCB resin plug hole, which comprises the following steps: firstly, using a jig and an air guide base plate to plug holes in the PCB by resin; after hole plugging is finished, transferring the PCB to a vacuum drying oven for bubble breaking; baking after the bubble breaking is finished; polishing the resin after baking; and after polishing, entering a subsequent production flow. The invention introduces a vacuum bubble breaking link and processes by lower vacuum degree and higher vacuum degree in sequence. The method has the advantages that the air bubbles on the surface of the resin are discharged under the lower vacuum degree, then the air bubbles in the hole are slowly discharged under the higher vacuum degree, and the ideal PCB resin plugging plate is obtained.

Description

Manufacturing method of PCB resin plug hole

Technical Field

The invention belongs to the technical field of circuit boards, and particularly relates to a manufacturing method of a PCB resin plug hole.

Background

Due to the strong trend of the miniaturization and multi-functionalization development of electronic products, the PCB serving as the parent of the electronic products is changed correspondingly, wherein the continuous development of the miniaturization of the PCB leads to more disk mesopore structures, and the welding points and the welding area which can be used for welding are continuously reduced when being seen from the surface of a plate, and the disk mesopore structure cannot be directly used as a welding point, because the disk mesopores easily cause solder to flow into the back along the pores, so that insufficient welding or short circuit is caused, the welding area of the disk mesopores is insufficient, and the reliability of welding points is poor; in order to solve this problem, the PCB must be subjected to a resin via hole process.

The traditional plug hole process is as follows: the hole plugging method comprises the steps of hole plugging, baking, resin polishing mechanically/manually, and transferring to a subsequent process, wherein pinholes, bubbles and the like are easy to appear on the surface of the resin in the resin hole plugging mode, welding is not facilitated, short circuits are easy to appear when the pinholes and the bubbles appear on a back drilling hole and POFV is needed in the subsequent process, and the problems of the pinholes and the bubbles on the surface of the resin can be solved by the conventional vacuum hole plugging machine.

Disclosure of Invention

The invention aims to provide a simple and feasible resin hole plugging processing method without large investment, and solve the problems of resin pinholes and air bubbles easily caused by the traditional resin hole plugging method.

The purpose of the invention can be realized by the following technical scheme:

a method for manufacturing a PCB resin plug hole comprises the following steps:

A. plugging the PCB with resin;

B. after hole plugging is finished, the PCB is placed at a constant temperature higher than room temperature for processing for a certain time, so that bubbles in the holes can slowly move to the orifices;

C. carrying out vacuum treatment on the PCB;

D. baking the PCB, polishing resin and transferring to subsequent production.

Preferably, in the step C, the vacuum treatment of the PCB comprises the following specific steps:

firstly, the PCB is subjected to pressure maintaining treatment for a certain time under the environment with the vacuum degree of B1, then the vacuum degree is adjusted to B2, and the pressure maintaining treatment is continued for a certain time, wherein B1 is more than B2.

Preferably, in the step B, the constant temperature higher than the room temperature is 30-50 ℃.

Preferably, when the resin plug holes are through hole resin plug holes, the hole diameter of each through hole resin plug hole is 0.2-1.0 mm, and the plate thickness is 0.2-3.0 mm, the treatment temperature is 30-40 ℃, and the treatment time is 30 min.

Preferably, when the resin plug holes are back-drilled resin plug holes, the hole diameter of the back-drilled resin through hole is 0.2-1.0 mm, the back drilling depth is 0.2-1.0 mm, the plate thickness is 0.2-3.0 mm, the treatment temperature is 40-50 ℃, and the treatment time is 45-60 min.

Preferably, in the step C, the vacuum treatment of the PCB comprises the following specific steps:

firstly, vacuumizing a vacuum drying oven until the vacuum degree is-0.05 Mpa, and after pressure maintaining treatment is carried out for 10min, continuously vacuumizing until the vacuum degree of the vacuum drying oven is-0.1 Mpa, and carrying out pressure maintaining treatment for 20-40 min.

The invention has the beneficial effects that:

the invention introduces a vacuum bubble breaking link and processes by lower vacuum degree and higher vacuum degree in sequence. The method has the advantages that the air bubbles on the surface of the resin are discharged under the lower vacuum degree, then the air bubbles in the hole are slowly discharged under the higher vacuum degree, and the ideal PCB resin plugging plate is obtained.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A method for manufacturing a PCB resin plug hole comprises the following specific steps:

s1, plugging the holes with resin by using a jig and an air guide backing plate;

s2, after hole plugging is finished, the plate is placed in a vacuum drying oven, and for through hole resin hole plugging (the hole diameter is 0.6mm, the plate thickness is 2mm), the temperature is kept for 30min at 40 ℃;

and S3, after constant temperature treatment, performing segmented vacuumizing, and specifically executing the following steps.

Keeping the vacuum degree at-0.05 Mpa for 10min to facilitate the direct overflow of bubbles on the shallow surface of the resin. Then continuously vacuumizing until the vacuum degree reaches-0.1 Mpa, and keeping for 30min to facilitate the slow overflow of air bubbles in the resin;

s4, after the vacuum treatment is finished, taking out the plate and baking the plate;

and S5, after baking, resin polishing is carried out.

Example 2

A method for manufacturing a PCB resin plug hole comprises the following specific steps:

s1, plugging the holes with resin by using a jig and an air guide backing plate;

s2, after hole plugging is finished, the plate is placed in a vacuum drying oven, and resin hole plugging (the diameter of a through hole is 0.6mm, the depth of a back drill is 1.0mm, and the plate thickness is 2.0mm) is carried out on the back drill hole at the temperature of 50 ℃ for 50 min;

and S3, after constant temperature treatment, performing segmented vacuumizing, and specifically executing the following steps.

Keeping the vacuum degree at-0.05 Mpa for 10min to facilitate the direct overflow of bubbles on the shallow surface of the resin. Then continuously vacuumizing until the vacuum degree reaches-0.1 Mpa, and keeping for 45min to facilitate the slow overflow of air bubbles in the resin;

s4, after the vacuum treatment is finished, taking out the plate and baking the plate;

and S5, after baking, resin polishing is carried out.

For resin hole plugging of a PCB, the traditional method cannot ensure the integrity of the resin surface, and under the normal condition, needle holes and the like are easy to appear on the resin surface. Inside the resin, there is also air residue;

the two defects cause very serious adverse effects on the reliability of the plate, specifically, if pinholes and bubbles appear on the surface of the resin, problems such as cold joint, loose welding leg and the like easily appear after POFV, and if the holes are back-drilled holes, short circuit easily appears after POFV;

the main current solution to this problem in the industry is the introduction of vacuum plughole machines. However, the vacuum hole plugging machine has large capital investment and higher operation proficiency for operators, and is difficult to popularize and apply on a large scale.

Aiming at the problems, the invention creatively introduces a vacuum bubble breaking link and processes the bubbles by lower vacuum degree and higher vacuum degree in sequence. And (3) realizing the discharge of air bubbles on the surface of the resin under a lower vacuum degree, and then slowly discharging the air bubbles in the hole under a higher vacuum degree to obtain the ideal PCB resin plugging plate.

The method provides a resin hole plugging method which is low in price and easy to operate, can meet the quality requirement of resin hole plugging manufacturing, and basically does not increase the production operation time and the production flow.

The foregoing is merely exemplary and illustrative of the present invention and various modifications, additions and substitutions may be made by those skilled in the art to the specific embodiments described without departing from the scope of the invention as defined in the following claims.

Claims (6)

1. A method for manufacturing a PCB resin plug hole is characterized by comprising the following steps:

A. plugging the PCB with resin;

B. after hole plugging is finished, the PCB is placed at a constant temperature higher than room temperature for processing for a certain time;

C. carrying out vacuum treatment on the PCB;

D. baking the PCB, polishing resin and transferring to subsequent production.

2. The method as claimed in claim 1, wherein the step C of vacuum processing the PCB comprises the steps of:

firstly, the PCB is subjected to pressure maintaining treatment for a certain time under the environment with the vacuum degree of B1, then the vacuum degree is adjusted to B2, and the pressure maintaining treatment is continued for a certain time, wherein B1 is more than B2.

3. The method as claimed in claim 1, wherein the constant temperature higher than room temperature in step B is 30-50 ℃.

4. The method as claimed in claim 3, wherein the processing temperature is 30-40 ℃ and the processing time is 30min when the resin plug hole is a through hole resin plug hole, the hole diameter of the through hole resin plug hole is 0.2-1.0 mm, and the plate thickness is 0.2-3.0 mm.

5. The method for manufacturing resin via holes of PCB as claimed in claim 3, wherein when the resin via holes are back-drilled resin via holes, and the diameter of the back-drilled resin via holes is 0.2-1.0 mm and the back-drilling depth is 0.2-1.0 mm, the thickness of the board is 0.2-3.0 mm, the processing temperature is 40-50 ℃ and the processing time is 45-60 min.

6. The method as claimed in claim 2, wherein the step C of vacuum processing the PCB comprises the following steps:

firstly, vacuumizing a vacuum drying oven until the vacuum degree is-0.05 Mpa, and after pressure maintaining treatment is carried out for 10min, continuously vacuumizing until the vacuum degree of the vacuum drying oven is-0.1 Mpa, and carrying out pressure maintaining treatment for 20-40 min.