Polytetrafluoroethylene (PTFE), also called Teflon, is a synthetic thermoplastic fluoropolymer that has excellent dielectric properties at microwave frequencies.
When design high frequency PCBs at microwave frequencies, the key characteristics that define PCB laminate performance for microwave/RF printed-circuit boards (PCBs) include dielectric constant(Dk), dissipation factor (Df), coefficient of thermal expansion (CTE), thermal coefficient of dielectric constant (TCDk), and thermal conductivity.
The most familiar to users of PTFE PCB laminates’ manufacturers include Isola, Rogers, Arlon, Taconic and Panasonic.