PCB designers should know more about PCB substrates

In today’s complex world of electronics design PCB designers need to understand which substrates materials to use and when.
This understanding will bring benefits in reliability and savings in cost. No more broken vias, better impedance control, less timing skew problems and no more mistakes made in selecting unnecessarily expensive grades of FR-4 or polyimide.

IPC-4101B Specification for Base Materials for Rigid and Multilayer Printed Boards (including RoHS compliancy data) is the most comprehensive stanadard available for making sure your impedance calculations have realistic figures and when the need to arises to talk to your fabricator about layer stack-up, borad thickness etc then you can readily appreciate how any changes may affect your design.