A special gold-plated pad manufacturing method

Abstract

The invention discloses a special manufacturing method for a gold-plated bonding pad. The method comprises the following steps: supplying a multi-layer plate, wherein one or a plurality of gold plating patterns are designed in a gold plating area on the surface of the multi-layer plate; protecting by utilizing a dry film, and locally electroplating one or more gold plating patterns with nickel gold; protecting the one or more gold plating patterns and a non-gold-plating area by utilizing films; etching the gold plating area to obtain one or more gold plating patterns as the gold-plated bondingpad; arranging anti-plating oil on the one or more gold plating patterns for protection, wherein the anti-plating oil is covered with an anti-plating film; protecting by utilizing the dry film; electroplating the surface patterns of the multi-layer plate with copper and tin; etching after removing the films to form a circuit pattern on the surface of the multi-layer plate; removing a tin layer onthe surface of the circuit pattern; and removing the anti-plating oil. According to the method, the gold plating patterns are etched in advance and are protected by the anti-plating oil, so that problems in the prior art can be solved or reduced.

Description

technical field [0001] The invention relates to the technical field of PCB, in particular to a special gold-plated pad manufacturing method. Background technique [0002] Some special PCB (Printed Circuit Board, printed circuit board) products require the gold-plated pads from the window to be lower than other graphics; for example, for some PCBs used in bonding, the gold-plated pads required to be bonded are lower than other graphics 20- 50um. This type of product also has some pads that are electro-gold first and then copper-plated. Therefore, the electro-gold area is larger than the gold-plated pads that come out of the last window. [0003] The production process of the prior art includes the following processes:...outer lamination → drilling → copper flash plating → dry film application, exposure, development → electro-gold → film fading → dry film application, exposure, development → graphic copper plating, Tin→film stripping→etching→pasting dry film, exposure, devel...

AI Technical Summary

Problems solved by technology

[0005] 1. In the process of graphic electroplating copper and tin, because the electro-gold layer is very dense, the bonding force between the electro-gold layer and the dry film is poor, and the graphic electroplating process takes a long time and there is vibration, and the dry film is easy to loosen, which makes the solder resist open The window gold-plated pad is easily plated with copper or tin, resulting in the scrapping of the board;

[0006] 2. Repeated film application and film fading can easily cause exposure deviation, especially the last exposure deviation can easily cause tin stripping potion, mainly dilute nitric acid, which corrodes the nickel plating layer

[0007] 3. Tin removal: The nickel plated layer on the side of the gold-plated pad with solder mask opening is easy to be corroded. In addition, the bonding force between the gold-plated pad and the dry film is poor. If it is loose, it will corrode the nickel-plated layer under the gold-plated layer

[0008] Because of the above problems, the overall yield of PCB boards is very low

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