Electroless Nickel Immersion Gold (ENIG) coating is a popular surface finish for printed circuit boards (PCBs), particularly in 4-layer configurations. This finish offers several advantages for complex electronic designs:
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Excellent Flatness: ENIG provides a remarkably flat surface, crucial for fine-pitch components and ball grid arrays (BGAs).
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Corrosion Resistance: The gold layer protects against oxidation, ensuring long shelf life and reliable solderability.
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Uniform Thickness: ENIG coating maintains consistent thickness across the board, enhancing performance in high-frequency applications.
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Multiple Reflow Cycles: It withstands multiple reflow cycles without degradation, ideal for dense, multi-layer designs.
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Wire Bonding Compatibility: ENIG is suitable for both soldering and wire bonding, offering versatility in assembly methods.
In 4-layer PCBs, ENIG coating complements the increased complexity, supporting high-density interconnects and improved signal integrity. While more expensive than some alternatives, ENIG’s durability and performance make it a preferred choice for many high-reliability applications in aerospace, medical devices, and advanced telecommunications.
