Hi Technetters,

We are currently running an 8 layer PCB, 1.6mm thickness. In the last run of
approx. 400 nos. we found approx. 10 nos PCBs with blisters in some specific
areas. In approx. 40-50 nos. the blistering is not there but the laminate
has discoloration.

Can anybody suggest any possible causes of the same.

We are not baking the PCBs prior to processing, but the boards are in vacuum
packing and the packing is opened only at the Stencil printing stage.

Any suggestions welcome

Regards
Vinit Verma
Flextronics Technologies (India) Pvt. Ltd.
88A, Electronic City, Hosur Road,
Bangalore-561 229
Tel: +91-80-852 0022, Ext. 161 ; Fax: +91-80-852-1022
E-Mail : [log in to unmask]

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