When corrosion-resistance and solderability are paramount in electronic circuits, the ENIG (Electroless Nickel Immersion Gold) PCB surface finish is frequently utilised. Among its many useful qualities are high resistance to corrosion, easy soldering, and reliable electrical contact, all of which are helping to expand its use across a wide range of industries. Following answers cover the most common inquiries people have about ENIG PCB.
What is ENIG PCB?
By use of chemical deposition, ENIG deposits a uniform layer of nickel-phosphorus on the top of a printed circuit board (PCB). The procedure produces an extremely smooth surface, making it suitable for usage in precision fields like aerospace and medicine. ENIG PCBs, with their sleek appearance and long-lasting corrosion protection, are the best choice for reliable products.
Key features of ENIG surface finish
● When compared to other types of plating, ENIG surface finish offers improved corrosion resistance, outstanding solderability, superior flatness, exceptional wear resistance, and is an environmentally responsible solution. These essential attributes make ENIG surface finish an attractive choice.
● Because of these characteristics, ENIG surface finish is a great option for the fabrication of electronics, including everything from circuit boards to phone casings.
● Due to the exceptional flatness of the ENIG surface finish, it is guaranteed that regardless of how detailed the design is, all of the components will align properly.
What metals can be plated with ENIG?
The plating of metals such as copper, steel, aluminium, brass, and zinc can be accomplished by the use of the ENIG process. When done correctly, ENIG plating results in a coating that is uniformly resistant to corrosion, has a long lifespan, and can be maintained at a cost that is affordable. The ENIG plating method results in a coating that is uniformly glossy and composed of nickel-phosphorus alloy. This layer is followed by the application of a very thin layer of gold.
ENIG PCB benefits and limitations
ENIG on a Printed Circuit Board (PCB) has a number of benefits.
● These include better soldering, higher resistance to oxidation and corrosion, and a more streamlined, aesthetically pleasing appearance.
● To top it all off, ENIG PCB can resist temperatures as high as 400 degrees Celsius and lasts much longer than alternatives like lead-tin soldering. As a result of its greater strength and endurance, ENIG PCBs are a great option for electronics that will be subjected to harsh environments.
● Since the gold layer may be placed to the surface of a printed circuit board with a straightforward chemical process, ENIG PCBs are likewise simple to produce.
There are a few limitations associated with the utilization of ENIG PCB.
● The ENIG PCB has a limit on both its current capacity and its resistance to thermal shock, and both of these levels are capped at particular levels. These printed circuit boards (PCBs) can only withstand currents of a specific strength due to the thinness of the copper plating that is utilized in their construction.
● Thermal shock is another factor that can easily cause the plating on ENIG printed circuit boards to break. This happens when the board is subjected to abrupt and severe shifts in temperature.
ENIG vs HASL(Hot Air Solder Leveling)
● ENIG is a type of surface finish that consists of an electroless nickel layer and a gold layer. HASL (Hot Air Solder Leveling) is a technique for smoothing out the surface of the circuit board, and ENIG is an acronym that stands for “Electroless Nickel Immersion Gold.”
● ENIG provides superior electrical performance, chemical stability, and high flatness, whereas HASL provides a thicker coating of solder for protection.
● HASL also gives a thicker coating of solder. However, ENIG possesses superior electrical performance, stronger chemical stability, and a gold layer that is significantly thinner and more protected against tarnishing than HASL’s gold layer.
Where can ENIG PCB be used?
ENIG PCBs, have a wide range of potential applications, some of which include the aerospace industry, the automobile industry, and medical electronics. In addition, ENIG PCBs are utilized in the production of consumer goods including as personal computers, tablet computers, and mobile phones.
What is the process of ENIG in PCB manufacturing?
The ENIG technique consists of two steps: first, a layer of electroless nickel is deposited, and then, after that, a layer of thin immersion gold is deposited.
These two steps are what make up the technique. The gold layer protects the electroless nickel coating from tarnishing, while the electroless nickel coating protects the substrate beneath it from rusting and corrosion. In addition to its use in the electronics industry, the electroless nickel and gold alloy, often known as ENIG, has a number of other potential applications.
Factors should be considered for ENIG plating
For successful ENIG plating, also known as Electroless Nickel Immersion Gold Plating, there are a few considerations that need to be taken into consideration.
● It is essential to give consideration to the substrate material because it has an effect on the quality and endurance of the plating.
● When getting ready for ENIG plating, it is essential to think about the working temperature, the pH level, and the amount of gold that is required.
● Chloride and sulphide ions are also present, and because they interfere with the plating process, their presence needs to be taken into consideration.
● It is also important to note that the ENIG plating procedure cannot be carried out in an oxidising atmosphere because doing so would generate subpar plating results.
Yes, the ENIG finish does not include any lead, and it is therefore suitable for use in applications that are required to comply with the RoHS directive of the European Union, which limits the use of hazardous compounds in electronic products.
No, Electroless Nickel Immersion Gold Plating (ENIG) is not magnetic because a protective layer of gold is formed over the nickel substrate, gold plating, also known as ENIG, does not exhibit magnetic properties. Despite the absence of magnetic characteristics, ENIG plating is an effective coating for protecting components against oxidation and corrosion.
Electroless Nickel Immersion Gold Plating is not technically a hard gold plating process, as the gold layer deposited is much thinner than other hard gold plating processes. However, it is much harder than standard gold electroplating processes due to the fact that the gold layer does not undergo a heat treatment process and therefore does not soften with wear
Yes, Electroless Nickel Immersion Gold Plating is conductive. This process is often used to protect electrical and electronic components, as the gold prevents oxidation on the surface of the nickel, while also providing a conductive layer.
Conclusion
Because of the improved durability and performance of components made possible by the low-level contact resistance between metal and substrate, expertise with ENIG PCB is more valuable in the present era. As ENIG PCBs have improved in quality and performance, they have found widespread use in fields including the automotive, aerospace, and medical electronics industries.
