Final surfaces for laser cavities

The following solder surfaces are available for laser cavities:

Nickel Gold (ENIG)

Immersion Tin

Nickel Gold (ENIG) 

Technical Info:

  • Electroless Nickel Immersion Gold    
  • Typ. Au-coat 0.05–0.1 µm  
  • Typ. Ni-coat 4 – 7 µm    
  • Process temperature ~ 80°C  
  • Max. shelf life 12 months  

Immersion Tin

Technical information:

  • Immersion Tin
  • Typ. Sb.coat 0.7–1 µm (max. 1.2 µm)
  • Process temperature ~ 70°C
  • Shelf life 6months

Advantages:

  • Universally suitable surface finish  
  • No Copper attack during soldering process, Nickel serves as diffusion barrier  
  • Smooth surface  
  • Soldering (with or without lead, mulitple soldering)  
  • Storing between solder processes is possible  

Advantages:

  • Smooth coating  
  • Good solderability / hole filling  
  • Suitable for press-fit applications because no burr appears  

Disadvantages:

  • Relatively expensive  
  • Certain limits for press-fit application

Disadvantages:

  • Sensitive on scratches  
  • Sensitive on thermal influence and improper storage conditions  
  • Only limited shelf life in semi-assembled condition  

Application fields:

  • Flex-rigid boards
  • Fine pitch structures and micro vias    
  • Al-wire bonding
  • Laser cavities

Application fields:

  • Fine pitch structures and micro vias  
  • HDI boards  
  • Press- fit applications  
  • Laser cavities