Composite activating agent for electroless nickel/immersion gold, preparation method of composite activating agent, and activating method

Abstract

The invention relates to the technical field of circuit boards, in particular to a composite activating agent for electroless nickel/immersion gold, a preparation method of the composite activating agent, and an activating method. The composite activating agent is prepared from the following raw materials in parts by weight: 1030-1150 parts of a solvent, 0.7-2.9 parts of a surfactant, 0.15-2.7 parts of palladium acetate, 0.02-0.05 part of copper sulfate, and 2.7-4.5 parts of a synergist. The preparation method comprises the following steps: uniformly mixing acetic acid, palladium acetate, 2-chloroethyl pyridine and 2-amino-5-nitrothiazole in proportion to obtain a mixture A, and then uniformly mixing the mixture A, a solvent, a surfactant and copper sulfate in proportion to obtain the composite activating agent. The activating method comprises the following steps: immersing a pre-treated circuit board in the composite activating agent, then taking out the uniformly immersed circuit board, washing with water, and air-drying to obtain the uniformly activated circuit board. According to the invention, the activating agent has the effect of reducing skip plating and burrs of the circuit board.

Description

technical field [0001] This application relates to the technical field of circuit boards, more specifically, it relates to a composite activator of chemical nickel and gold, a preparation method and an activation method thereof. Background technique [0002] The circuit board is an important electronic component and a carrier for the electrical connection of electronic components. Among them, chemical nickel gold is a processing technology mainly used for the surface treatment of circuit boards. Sodium hydrogen phosphate is dissolved to generate atomic hydrogen. At the same time, under the catalytic conditions of palladium, the hydrogen atom reduces the nickel in the electroless nickel plating solution to simple nickel, and a layer of nickel-phosphorus alloy is electrolessly plated on the surface of the circuit board. A layer of gold is plated on the surface of nickel by substitution reaction. Since this process can effectively reduce the oxidation or corrosion of copper on ...

AI Technical Summary

Problems solved by technology

In the existing activation treatment, palladium sulfate solution is generally used as the activator, but due to the poor binding force of palladium sulfate to the copper on the surface of the circuit board, the palladium element that cannot be combined on the surface of the circuit board will be free in the solution in the form of ions. In this process, the distribution of palladium metal atoms on the surface of the circuit board is uneven, and subsequent missing plating and burrs are prone to occur, which affects the production quality of the circuit board.

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