There are some differences in principles, applications and processes between PCB immersion gold and electroless gold plating.
1. Principle: The immersion gold process uses chemical deposition to generate a layer of coating through the principle of chemical oxidation-reduction reaction, usually a nickel-gold alloy. Electroless gold plating uses a chemical reducing agent to reduce metal ions into metal elements and deposit them on the surface of the substrate.
2. Application: The immersion gold process is widely used in the PCB field, and immersion gold boards are usually used in circuit boards of high-end electronic products. Chemical gold plating is mainly used to make decorative gold plating or functional gold plating, such as solder joints of electronic components.
3. Process: The immersion gold process usually includes two steps: nickel immersion and gold immersion, which require the use of chemical nickel gold solution and chemical immersion gold solution. Chemical gold plating usually includes steps such as solution preparation, plating, and recycling, and requires the use of chemical gold plating solution and other auxiliary materials.
In general, although PCB immersion gold and chemical gold plating are both circuit board surface treatment technologies, they are significantly different in many aspects. The specific choice of process depends on factors such as product performance requirements, application fields, and usage environment.