This is not an area where I have any current information other than what's
in other specifications.  What's shown here as being in 6012 looks like
something that was converted from metric.  IPC-6015 says for Gold to be wire
bonded, (thermosonic) 0.3, 0.5, and 1.0 micrometers for classes 1, 2 and 3.
Ultrasonic is much lower but I think the bond there is to the underlying
Nickel.
 Such being the case, if someone is using it like TRW, I would vote to go
with what they specify which means we should take a look at it..
----- Original Message -----
Wrom: AUTFJMVRESKPNKMBIPBARHDMNNSKVFVWRKJVZ
To: <[log in to unmask]>
Sent: Friday, June 28, 2002 2:03 PM
Subject: [IPC-600-6012] Increase Wire Bondable Gold Plating min values for
IPC-6012B?


Colleagues,

Following our intitial review of the Proposed Table 3-2 for the IPC-6012B,
several task group members indicated that they specifiy minimum values of
wire bondable gold electroplating, for both ultrasonic and thermosonic
conditions, decidedly different from that of the IPC-6012B.

TRW specifices a minimum of 0.0001" for Class 3 for both GWB-1 and GWB-2.
Soverign Circuits has indicated that NASA specifies a nominal 0.0001" for
wire bondable gold.

IPC-6012B is calling out 0.00000197" for GWB-1 and 0.0000118" for GWB-2.

Is it the consensus of this group that we should explore increasing the
minimum thickness for this type of plating under Class 3, or that we should
keep the values as is and allow board fabricators to take exception within
their procurement documentation when necessary?

The proposed table is attached here - I hope - we've had problems in the
past posting to forums with attachments, but I've been told  that has been
fixed.

Best Regards,



John Perry
Technical Project Manager
IPC
2215 Sanders Road
Northbrook, Il 60062
1-847-790-5318 (P)
1-847-509-9798 (F)
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