Electroless Nickel / Immersion Gold

    Electroless Nickel / Immersion Gold Process not as simple as the organic coating, electroless nickel / Immersion Gold PCB like to wear thick armor; other Electroless Nickel / Immersion Gold Process is also not as rust-proof barrier layer of organic coating It can be useful during long-term use PCB and achieve good electrical properties. Therefore, electroless nickel / Immersion gold is wrapped in a thick layer of copper surface, good electrical properties of nickel gold alloy, which can be long-term protection PCB; In addition, it also has other surface treatment not available in the environment of the patient sex. Nickel is due to be mutual diffusion between gold and copper,
    The nickel coating to prevent the spread between gold and copper; If there is no nickel, gold will be in a few hours to spread to the copper. Electroless Nickel / Immersion Gold, another advantage is the strength of nickel, nickel thickness of only 5 microns high temperatures can limit the expansion of Z direction. In addition, electroless nickel / Immersion Gold also can prevent the dissolution of copper, which will benefit the lead-free assembly.
    Electroless Nickel / Immersion Gold Process general procedures: acid cleaning → Etching → prepreg → activation → → Electroless Nickel Immersion Gold, there are six major chemical tanks, involving nearly 100 chemicals, so comparison of process control difficult.