I would be grateful if someone could give me information, or a document(s) 
 to
reference on the post mechanical drill cleaning of multi-layer PC boards. I
am looking for references to:

a) De-smearing, the chemicals commonly used,  the cost and why this would
be necessary.
b) Etch-back with the above information.
c) Pumice wash with the above information.
d) Any other cleaning techniques in common use.

Many thanks in advance.

Alan Cable
Electro Scientific Industries