HASL, ENIG, or Immersion Silver? Many people hesitate to choose the right surface finish when making PCBs—here’s how to pick the best one in 30 seconds!
 
Hot Air Solder Leveling (HASL): Lowest cost with excellent solderability, but its surface is not flat enough, making it less suitable for fine-pitch components.
 
Electroless Nickel Immersion Gold (ENIG): Features a flat surface and superior conductivity, ideal for high-end boards with high-density BGAs and precision soldering—though the cost is relatively higher.
 
Immersion Silver (ImAg): Offers stronger conductivity and lower signal loss, the top choice for high-frequency and high-speed circuits. Note that its surface is prone to oxidation and requires proper storage.