Blind and buried vias in hybrid PCBs need a layer-span map, material review, build sequence, fill rules, and hidden-feature evidence before RFQ release.
RF edge launch PCB thickness must match connector hardware, local stackup, routed edge, copper, mask, assembly, and first-lot RF evidence before release.
High frequency hybrid PCB stackup RFQs should define RF layers, FR4 layers, material compatibility, impedance evidence, and lamination risk before build.