Through hole electroplating and filling method and preparation method of printed circuit board

Abstract

The invention discloses a through hole electroplating and filling method and a preparation method of a printed circuit board. The through hole electroplating and filling method comprises the followingsteps: S1, carrying out reversing pulse electroplating on a to-be-plated substrate with a through hole by utilizing pulse electroplating liquid; and S2, carrying out hole filling treatment on the through hole treated in the step S1. Wherein the pulse electroplating solution contains metal ions to be plated, halogen ions and an accelerator, the accelerator comprises organic sulfonate, and the concentration c of the organic sulfonate meets the following relational expression: c is equal to or more than 1 ppm and less than 8 ppm; and the reversing pulse electroplating adopts PPR square wave current with at least one turn-off time, and the single turn-off time ranges from 20 ms to 80 ms. According to the scheme, the pulse electroplating liquid is combined with PPR electroplating to realize the situation that the electroplating efficiency in the middle of the hole is higher than that in a hole opening and surface copper in the electroplating process, so that protrusions exist on the surface of the copper in the hole, plating starting points are provided for hole filling lotion, and then electroplating hole filling is achieved.

Description

technical field [0001] The invention relates to the technical field of printed circuit board preparation, in particular to a through-hole electroplating and filling method and a method for preparing a printed circuit board. Background technique [0002] Printed circuit boards (PCB), also known as printed circuit boards, are providers of electrical connections for electronic components. With the development of electronic products in the direction of miniaturization, convenience, and intelligence, the assembly density and integration of components on printed circuit boards also increase. Especially with the development of 4G and 5G communication technologies, the signal transmission volume, transmission The requirements for speed and transmission distance are getting higher and higher. As the main carrier of electronic signal transmission, printed circuit boards are also developing towards high frequency, high power, miniaturization, and high-density concentration of component...

AI Technical Summary

Problems solved by technology

However, this process is prone to drill deviation on both sides (such as figure 2 As shown) and the thickness of the core board exceeds 10mil, poor hole shape and other problems, resulting in poor subsequent use effect

At present, there is no direct filling and leveling process of mechanical hole filling. The main reason is that the wall of the mechanical drilling hole is flat, and the additives in the hole filling potion cannot form a significant gradient difference after adsorption, that is, there is no starting point for plating, and it cannot be filled and leveled.

Images