In a message dated 1/25/01 5:30:19 PM Eastern Standard Time,
[log in to unmask] writes:

<< After drilling, these boards go through Blackhole graphitic carbon / Cu
flash / image / Cu pattern plate with Sn as etch resist / strip dry film,
etch Cu and strip the Sn/ LPI and HAL. >>

Sandy,

How are you getting the graphite into the holes? Are you using something like
IBM's Fluidhead Technology, or simple immersion?

Are the circumferential voids only in the vias?

Are they truly circumferential (and not just on the glass bundle
terminations)?

Do you perform a conditioning bake before drill?

What desmear process are you using?

How "clean" are your holes out of drill?

I'll e-mail you directly..........

Bob Lazzara
Circuit Connect  --  Atlanta
(800) 560-9457

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