Michael Martinez <[log in to unmask]> Wrote:
| 
|      Hello All those in Technet,
|      
|      I am in dire need of information concerning gold plating 
|      specifications. I am researching two processes gold 
| flash and gold 
|      plating and would like to know if there are any articles 
| or sources 
|      that will shed any light to these two different 
| processes. I do know 
|      that gold flash is a less expensive approach than 
| plating, but I would 
|      like to know all draw backs to it. Any information will 
| be greatly 
|      appreciated.
|      
|      Thanks,
|      Mike 
|      
|      [log in to unmask]
| 

Mike:

MIL-G-45204 is a good spec for gold flash (immersion gold) and QQ-N-290 is 
a good spec for underlying Ni layer (eletroless Ni). IPC-2221 (working 
version) is a good reference for Ni layer thickness. The advantage of 
this technology is better coplanary and anti-corrosion.  The draw back 
will be solderability, shelf life, Au porosity, P content (8-10% is the 
upper limit) in Ni and strength of intermetallics.  It is know that Au-Sn 
intermetallics is weaker than Cu-Sn intermetallics.

Some good readings are *Effect of Aging on the Strength and Ductility of 
Controlled Collapse Solder Joints" by K. Banerji and R. Darveaux of 
Motorola , *Materials Developments in Microelectronics Packaging:  
Performance and Reliability* by D.R. Frear, f.M. Hosking and P.T. Vianco 
of Sandia National Lab, *Microstructure of Electroless Nickel-Solder 
Interactions by V.F. Hribar, J.L. Bauer, and T.P. O'Donnell from 
California Institute of Technology.

Nora

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