We have some products that are bare copper (no OSP) and are for
microwave/RF applications.  The application also requires bonding to the
copper surface.  This is a IPC-6018A product and not 6012 but maybe could
be for the right application.  I suggest leaving it in with the appropriate
verbage of caution etc.

Regards,

Mike Luke
Raytheon



                                                                           
                                                                           
             John Perry                                                    
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             <IPC-600-6012@IPC                                             
             .ORG>                                                 Subject 
                                       [IPC-600-6012] Bare Copper as a     
                                       Surface Finish                      
             02/04/2008 02:53                                              
             PM                                                            
                                                                           
                                                                           
             Please respond to                                             
             "(Combined Forum                                              
               of D-33a and                                                
                   7-31a                                                   
              Subcommittees)"                                              
             <IPC-600-6012@IPC                                             
                   .ORG>                                                   
                                                                           
                                                                           
                                                                           




Colleagues,



Our IPC-6012B specification provides for bare copper as a final finish
in Table 3-2, Final Finish, Surface Plating and Coating Thickness
Requirements.



The task group is evaluating whether or not this should be removed from
Table 3-2 in the future IPC-6012 Revision C.  Among the concerns with
bare copper are instances of single-sided via protection that provides
for entrapment of chemistries that attack the bare copper in the hole
wall.



If there are those of you out there who use bare copper as a surface
finish, could you provide feedback to IPC as to how it is used in your
applications?



Thanks in advance,



John Perry

Technical Project Manager

IPC

3000 Lakeside Drive # 309S

Bannockburn, IL 60015

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1-847-597-2818 (P)

1-847-615-7105 (F)

1-847-615-7100 (Main)