Hello,
      
     It is time and place i think to start to take decisions on that  
     whiskers growth test .Most of the world wide experts i guess are  
     around that forums.
      
     Among the results we built and we have seen from others , it is clear  
     than hot storage above 80°C will reduce whiskers growth , the best  
     test to accelerate a room temperature growth (shelf storage) is to  
     store at 50-55°C .
     It is may be not the only test to be performed but it must be  
     performed .
     The other option is likely to be a humidity & temperature storage  
     test which can range from 30°C60%rH which is about room temperature  
     of a clasiic store to 95°C-95%rH recently proposed by a forum member  
     form OMRON.
      
     I suggest to move ahead and each forum member to engage its company  
     about the necessity to provide storage data at 50° to 55°C in dry air  
     when speaking about whiskers.
      
     Beside lets open the door for a second or third test conditions on  
     which you may need more data to all commit and may even be customized.
      
     Data must be provided with a maximum length which may be drawn from  
     the inspection system : for example no whiskers means no whiskers  
     longer than X µm or mils .
      
     We do need in ST Microlectronics to receive that storage data (at  
     50-55°C) from any supplier ( process supplier or assembly  
     subcontractor ) when speaking about coatings with less than 5%  
     allowing element.
      
     Please vote on that proposal  
      
      
     Secondly i propose to vote also on the accepation of the fact that  
     reflow tin , tin dipped coatings do not grow whiskers.
      
      
     I am sure that base on that poll results a standard can be prepared by  
     IPC or other relevant organizations
      
      
      
        best regards
      
           Luc P.

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