De:   Coderre - JCCODERR BRMVM1
***************************************************************
CLASSIFICATION    NON-CLASSIFIE ( )       CONFIDENTIEL ( )
Objet:   Skip plating
Reply:
<Reply>
As an electroless nickel/gold shop, we have seen this condition in
some cases. The suggested analytical approach is as follows:
  - good visual inspection at high magnification
  - SEM + EDX analysis
  - Auger analysis
Please check to see if the defect is repetitive (it sometimes is).
If so, use these techniques prior to plating.
Hope this helps...

Jacques Coderre
IBM Microelectronics
Plating engineering manager
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 Subject: Exposed copper after electroless nickel gold
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 Recently we encounter exposed copper problem after electroless nickel
 gold process ,
 we wish to know if there any way to determine the stubborn film on top
 of the copper
 that prevent the plating to take place . We understand that soldermask
 on pad or
 poor rinsing after final development could give rise to such problem .
 Such problem
 of soldermask on pad could be easily found after HAL but cases of minor
 soldermask
 on pad could not be detected in HAL . Please advise .

Merci/Regards
Directeur Ingenierie MLC / MLC ENG. MGR
Dept 881/23 BRMT (tel. 514-534-6591, US tieline 552)
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