PCB Surface Finish Comparison

All PCB surface finishes have strengths and weaknesses. We're here to help you choose the best PCB materials for your project needs. Use the matrix below to assess the pros and cons of each material, to find the best fit for your circuit board and PCB finish needs.

PCB Surface Finishes

Please review the information below for a side-by-side comparison of PCB surface finishes.

Final Finish Comparison Matrix Interpretation Immersion Silver (IAg) ENIG (Electroless (Ni/Imm Au) Organic solderability coatings (OSP) Immersion Tin (ISn) HASL
(no-lead) 		HASL (Tin/lead)
Lead free compatible, RoHS compliant Required yes yes yes yes yes no
Solder joint integrity (how good and reliable is the solder joint)
very good * good good good good  best
Shelf life (with proper storage**)   12 months** 12 months 12 months** 12 months** 12 months 12 months+
Assembly heat cycles (# of passes through reflow) > is better multiple multiple multiple multiple multiple multiple
Fab thermal shock (thermal shock during PCB fabrication) very low is best very low
  low* very low very low
 high high
Wettable (how easily does the solder flow onto the surface)
very good* good good good acceptable *
 best
Solder paste printability (co-planarity of the finish for fine pitch devices)   excellent excellent excellent excellent poor poor
Solder pot compatible (low possibility of solder pot contamination) desirable yes monitor Au concentration
 yes yes yes no (if using no lead solder pot)
Low contact resistance (resistance of the finish) yes is good yes yes yes no no no
Aluminum wire bonding (can this finish be used with Al wire bonding) yes is good yes yes no no no no
Process cost to PCB fabricator
med high low med high low

Sources: (1) Cookson Electronics, (*) Sunstone testing data (**)