In recent years, the process of PCB resin plug hole has been widely used in PCB industry, especially in some products with high layers PCB and large PCB board thickness. People hope to use PCB resin plugging holes to solve a series of problems that can not be solved by using green plug holes for PCB or resin filled PCB resin. However, because of the characteristics of the resin used in this process, many difficulties need to be overcome in manufacturing, so as to achieve good quality of resin plugging products.,
Origin of PCB resin plug hole:
The development of electronic chips:
With the continuous update of electronic product technology, the structure and installation of electronic chips are also constantly improving and changing. Its development is basically from the parts with plug-in feet to the highly intensive integrated circuit module with ball matrix layout of solder joints. From the figure below, you can see the development process of parts:
The earliest CPU
286cpu (plug-in pin)
Pentium Series CPU (plug-in pin)
Ball array dual core CPU
Server CPU
The meeting of two people makes the technology of resin plug hole：
In PCB industry, many process methods have been widely used in the industry, and people are not very concerned about the origin of some process methods. In fact, as early as the ball matrix array of electronic chips just came into the market, people have been planning for small chips to mount components, hoping to reduce the size of their finished products from construction.
In 1990s, a Japanese company developed a resin that directly plugged the hole and then plated copper on the surface. The main purpose was to solve the problem of air blowing in green plug holes. Intel applied this process to Intel's electronic products, and the so-called pofv (part of the factory is also called via on pad) process was born.
3. Application of resin plug hole:
At present, the technology of resin plug hole is mainly applied to the following products:
3.1 Resin Plugging for POFV technology.
3.1.1 technical principle
A. plugging the through hole with resin and copper plating on the surface of the hole.
Tradition design
BGA pad plug with resin
3.1.2 advantages of pofv Technology
1. Reduce the space between holes and the area of the plate,
L. solve the problems of wire and wiring, and improve the wiring density.
3.2 inner HDI resin plug hole
3.2.1 Technical principle
Use resin to plug the embedded hole of inner HDI PCB, and then press it. This process balances the contradiction between the thickness control of the pressed dielectric layer and the HDI pcb inner hole filling design.
1. If the HDI embedded hole in the inner layer is not filled with resin, the plate will explode when it is impacted by overheating, so it will be scrapped directly;
L, if resin plugging is not used, it is necessary to press PP to meet the needs of filling. However, the thickness of the dielectric layer between the layers will be thicker due to the increase of PP film.
3.2.2 example:
3.2.3 Application of inner HDI PCB resin plug hole:
1. The inner HDI resin plug hole is widely used in HDI PCB products to meet the design requirements of thin media layer of HDI PCB products;
l, for blind buried products designed with buried holes in the inner HDI PCB, because the medium combination design is thinner, it is often necessary to increase the flow of inner HDI PCB resin plugging holes.
L, part of the blind hole products because the thickness of the blind hole is greater than 0.5mm, the filling and filling can not fill the blind hole, and also need to fill the blind hole PCB with resin plugging hole, so as to avoid the problem that there is no copper in the blind hole of the subsequent process.
3.3 Through hole resin plug hole:
In part of the 3G products, because the thickness of the board is more than 3.2mm, in order to improve the reliability of the product or to improve the reliability of the green plug, the resin is used to plug the through-hole under the permit of the cost. This is a major product category that has been popularized in recent years.
