PTFE (polytetrafluoroethylene) material, better known as Teflon, is the ideal dielectric in Radio Frequency pcb applications, but it is not easy to be coupled with the standard dielectrics (FR4) used in common pcb manufacturing.

Rogers (essentially a low loss ceramic dielectric) is currently the most used material in multilayer boards, i.e. rigid pcb, for Radio Frequency applications. It can be used as the sole dielectric (low layers count rigid pcb) or in the outer layers, when an inner realised with standard FR4 is requested. The reason why the use of Rogers is limited to the outer layers resides in the fact that the active components (antennas) that make the all pcb to become an active component, are typically printed only in the outer layers being the inner layers essentially interconnections.

Even if Rogers is the most used and known dielectric for these kind of applications, it is not the only choice that pcb manufacturer have: NELCO N4000 is, for example, a good alternative.

Some recent experimentation has also showed that it is possible to manufacture multilayer rigid pcb for Radio Frequency applications up to 70GHz using only FR4 dielectrics, as well.