A processing method for cooling holes of printed circuit board pcb

Abstract

The invention provides a processing method of heat radiating holes used for PCB. The electroplating layer of the internal wall of the heat radiating holes can be additionally arranged so that the influence on the thickness of the surface electroplating layer of the PCB can be reduced and design of the external line of the higher density is facilitated. The processing method comprises the steps that at least two layers of PCB daughter boards are pressed together to form the PCB, an internal conductive layer is arranged between any two adjacent layers of PCB daughter boards and the internal conductive layer at least comprises a target internal conductive layer exposed out of the side wall; the PCB is drilled so as to obtain the heat radiating holes penetrating through the PCB; first electroplating is performed on the PCB so that a first electroplating layer is enabled to be deposited on the external wall of the PCB and the internal wall of the heat radiating holes; window opening is performed on the first electroplating layer deposited on the upper surface and the lower surface so that the first region and the second region of the upper surface are enabled to be disconnected, and the third region and the fourth region of the lower surface are enabled to be disconnected; and second electroplating is performed on the heat radiating holes through at least one target internal conductive layer so that a second electroplating layer is enabled to be deposited on the internal wall of the heat radiating holes and the first region.

Description

technical field [0001] The present application relates to the field of printed circuit boards, and more specifically, relates to a method for processing thermal vias of printed circuit boards (Print Circuit Broading, PCB). Background technique [0002] With the development of network products, people require that the output power of the power converter is continuously increased, and at the same time, it is hoped that its size can be further reduced. At present, the commonly used power conversion devices are surface mount power converters (referred to as surface mount power tubes), and surface mount power tubes usually dissipate heat through printed circuit boards, which puts forward requirements on the heat dissipation capacity of PCB boards. [0003] In the current technology, heat dissipation is achieved by pre-processing heat dissipation holes in the PCB. A heat conduction layer with high thermal conductivity (for example, copper plating) is electroplated on the inner wa...

AI Technical Summary

Problems solved by technology

[0004] However, with the challenges brought about by the high-density design of wireless single boards and the challenges brought about by high-speed and high-frequency heat dissipation, it is required to realize heat dissipation on the basis of high-density and fine lines.

However, if the thickness of the conductive layer on the surface of the PCB is too large, it is not conducive to the layout of uniform thin lines; even if the thickness of the thermal conductive layer is reduced by grinding the plate, the grinding process leads to uneven surface of the PCB, which is also not conducive to the layout of uniform thin lines

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