IPC-2221 (table 4-3) has the following information:

Gold (min) on areas to be wire bonded (ultrasonic)
Class 1:   0.05 um  (micrometers)
Class 2:   0.05 um
Class 3:   0.15 um

Gold (min) on areas to be wire bonded (thermosonic)
Class 1:   0.3 um
Class 2:   0.3 um
Class 3:   0.8 um


Lisa Williams
Technical Project Manager
IPC
2215 Sanders Road
Nortbrook, IL  60062
www.ipc.org

>>> "(Eden Chen)" <[log in to unmask]> 09/25/98 04:16AM >>>
     Dear Member,

     I like to know the minimum thickness of bondable gold over nickel for
     gold wire and aluminum wire. Which standard can i refer to?


     Thank you very much.


     Eden

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