Hello !
In IPC specification ANSI/IPC-RB-276, 1992, for "Qualification and Performance Specification 
for Rigid Printed Boards" it is specified a copper thickness of 15µm for buried and blind vias 
with a min.thickness of 13µm. However this spec. was changed during 1996, IPC-6012, there the 
copper thickness for blind vias were increased to an average thickness of 25µm with a min. 
thickness of 20µm.

Does anyone know why they changed their specifications? 
Is there someone who has any experience of blind and buried vias with thin copper coatings 
(15-13µm)?

Thanks in advance for your help

                 //Markus



Markus Gauffin  M.Sc.
Printed Board Assembly Technology
tel: +46 8 719 16 34
fax: +46 8 719 71 99
e-post: [log in to unmask]

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