flex circuitStandard Flex Circuit Finishes

  • Hot air solder level
  • Immersion gold over electroless nickel (enig)
  • Immersion tin (white tin)
  • Electroplated soft or hard gold over electroplated nickel (both phosphorus and low sulfamate)
  • OSP (Organic Solderability Preservative) limited use

RoHS Compliancy

  • Bare flex circuits are RoHS compliant as long as they have a RoHS compliant surface finish
  • The main problem with RoHS circuits is via reliability
  • The different CTE’s (coefficient of thermal expansion) in the materials must be matched more closely in high end designs

Download Gold Plating Matrix for Hardness Requirements