What is the difference between ENIG and ENEPIG?
ENEPIG is similar to ENIG in both utilize electro-less nickel on top of copper plating; the difference is while ENIG has gold deposited directly on top of nickel, ENEPIG has an additional layer of palladium between the nickel and final gold layer (see below Fig. 1).
Is Enepig wire bondable?
ENEPIG (Electroless Nickel, Immersion Palladium, Immersion Gold) was derived out of the need to combat the challenge with the immersion gold process and Black Pad Syndrome. This keeps the gold deposit pure and readily accommodating to wire bonding, a process not able to be performed on standard immersion gold.
What is ENIG plating?
Electroless nickel immersion gold (ENIG or ENi/IAu), also known as immersion gold (Au), chemical Ni/Au or soft gold, is a metal plating process used in the manufacture of printed circuit boards (PCBs), to avoid oxidation and improve the solderability of copper contacts and plated through-holes.
Is Enepig lead free?
ENEPIG came through with flying colors as it formed one of the most robust solder joints with lead-free SAC type alloys.
Can you wire bond to ENIG?
ENIG is an ideal surface for aluminum wire bonding. However, with only 2- 4 micro-inches of gold it is not suitable for gold wire bonding. Soft gold at 10 – 25 micro-inches is needed for successful gold wire bonding. This may be achieved by depositing electroless gold on top of the ENIG finish.
What is black pad?
Black pad is a term that usually refers to nickel corrosion on electroless nickel and gold immersion (ENIG) surface finishes on PCBs. The defect is not seen as part of normal QC procedures as the immersion gold masks the appearance of the nickel under the gold.
What is Enepig surface finish?
ENEPIG is a type of surface finish done on copper layer to protect it from oxidation and corrosion in printed circuit boards. This surface finish improves the solderability of copper and is also RoHS compliant.
What is immersion gold plating?
Immersion Gold Plating is a process that applies a very thin layer of gold by displacement of the surface atoms. This means the coating is not very thick, typically between three and eight micro inches. It offers some corrosion resistance and is used to extend the shelf life of parts waiting for soldering operations.
What is Enepig finish?
How is ENIG applied?
Che Ni/Au or ENIG is a chemical process, applied after solder mask that adds 3-6µm Nickel before adding between 0.065µm and 0.10µm Gold onto the copper.
Can you wire bond to Enig?
What is plating in PCB?
Plating on a PCB refers to the electrochemical process by which a metal is deposited onto the surface of the circuit board, and inside the plated through-holes. The most common plated metal in PCB fabrication is copper.
What do you mean when you say ENEPIG?
When talking about ENEPIG, you are referring to a process of metal plating on a PCB. You are joining one metal to a conductive surface to finish the piece off. Quite commonly metal plating is associated with jewelry, but it is an essential process for building PCBs. Often you would see gold and silver plating.
What does ENEPIG stand for in surface finish?
ENEPIG is a type of surface finish done on copper layer to protect it from oxidation and corrosion in printed circuit boards. This surface finish improves the solderability of copper and is also RoHS compliant. ENEPIG stands for Electroless Nickel Electroless Palladium Immersion Gold.
How is ENEPIG formed in the PCB process?
ENEPIG is formed by the deposition of electroless nickel, followed by electroless palladium, with an immersion gold flash. It is suitable for soldering, gold wire bonding, aluminum wire bonding, and contact resistance. RoHS requirements, and increased focus on package reliability, have heightened interest in ENEPIG.
Why does ENEPIG have a long shelf life?
ENEPIG also shares similar benefits to ENIG in that it has a long shelf life due to its durability and resistance from tarnishing. Helps to prevent “Black Pad”: no possibility of grain boundary corrosion of nickel surface by immersion gold