Main construction content:
Metallized holes are the most important technical process in printed circuit boards. All interconnections are done by wires and metallized holes, especially for the inner layers of multilayer boards to achieve the purpose of connection, they must be done through metallized holes. Therefore, the role of the metalized hole is very huge, and once a problem occurs in the working circuit board due to the metalized hole, the loss it brings is even more unimaginable. For example, the artillery system of a tank is working on the battlefield. Suddenly, the signal is interrupted due to the internal cracking of the metalized hole. The artillery system will not work and directly make the tank a live target in the battlefield, so it is necessary to improve the reliability of metallized holes.
Core technology products and application value:
The core of this technology is to solve the problem of open circuit caused by metallization of metallized holes under severe weather conditions through the improvement of production technology. The solutions are as follows:
First, strengthen the treatment of the dirt on the hole wall before the metallized hole PTH to ensure that there is no dirt in the hole.
- Strictly control the life of the drill bit to ensure good chip removal from the drill bit.
- Clean the vacuum cleaner in time to ensure enough suction power to suck all the dust in the hole.
- After grinding the peaks, use the cleaning machine in the hole to remove the dust in the hole.
Second, increase the control of the copper sinking process to ensure that the metallized hole backlight is detected to level ten.
Each chemical liquid tank is equipped with a side spray flow pipeline to ensure the circulation of the chemical water and the penetration of the chemical water in the hole.
- Choose the products of top international pharmacies to confirm the quality of PTH.
- Strictly control the operating parameters and improve the quality of PTH.
Third, use compact plating cylinders to increase the plating control of metallized holes.
- The precision electroplating cylinder is equipped with spray measurement and two-dimensional swing settings to confirm the quality of the hole copper and the uniformity of the board surface.
- Adopting dual power supply and dual output method, good current distribution and electroplating copper quality.
- The use of rollers to entrain the floating bed makes the swing more reliable and ensures that the quality of the hole copper is improved.
Fourth, perform hole filling or resin plugging treatment for metallization.
- Use the electroplated hole-filling cylinder to do hole-filling treatment for the metallized holes, that is, the metallization is electroplated to fill the holes without gaps, and the metallized holes are filled to significantly improve the connection quality of the metallized holes.
- At this stage, the hole-filling technology cannot be filled with some metallized holes with larger diameter due to the limitation of the medicine and the power supply. Therefore, it is necessary to use the vacuum resin hole technology to plug the larger holes with resin or copper paste. The method of hole fills the hole to reduce the possibility of hole cracking and improve the conduction quality of the metallized hole.
- Whether it is a metal filling hole or a resin plug hole, the copper paste plug hole needs to be polished and the surface is plated with copper on its basis. The purpose is to improve the reliability of the metallized hole.
