Norm,

I agree 100%. 

Now you are at the point where the shop has ~95% of the Cpk's >1.33 for the 
product specified. The quality systems are in place, process/equipment matching,
measurement tool analysis, DOE, process control system, etc, etc, etc.

The PPM level to your customer is ~300. What now? 

Note: I have heard that there are some customers that allow a certain amount of 
open traces on the outer layers. It seems like the customer accepted that opens 
were a fact of life and was not pushing or counting opens in the PPM 
calculations. Does anyone know if this is true?

We know that 300 PPM is not good enough. What is the method you want to use to 
reduce the level of defects? 

The buy back scheme is obviously the stick, but what should the carrot be? We 
have worked hard to develop a two way street for PB spec changes to better fit 
the PB process while pushing to resolve opens, delamination and missing/damaged 
pads, etc. (I am not talking about the special causes either. We are really 
dealing with common cause variation.) Opens are caught at functional test and 
reworked or scrapped, but should these rolled into the cost of quality model and
forgotten? Even so, who should pay for the lost components?

What do most PB shops do when they get out of spec material? Do you all charge 
for that material only-laminate, drill bits, bulk H2SO4- or do you charge a 
fixed negotiated price depending on WIP location?
 
I guess I am asking for specifics, some idea from the PB community as to where 
they want to go and what they do with their suppliers.

Steve