This is a brief description of our Immersion Silver process:

• Immersion silver is applied directly over copper and provides an excellent solderable surface and as an HASL replacement.  It is used commonly for metallic dome contacts, membrane switches, EMI shielding, and aluminum wire bonding.
• Our Immersion Silver meets the requirements of IPC 4553.  The typical thickness's are 4-16 uin. 
  Note: We discourage thicker deposits above 16 uin as Immersion Silver can attack copper due to the aggressive nature of the chemistry.