High Frequency PCBs
Nowadays, high frequency PCBs are widely used in high-tech devices. Generally speaking, high frequency can be defined as frequency above 1GHz. However, Teflon material is widely used in high frequency PCB manufacturing currently, whose frequency is normally above 5GHz. In addition, FR4 or PPO substrate can be used to those products whose frequency is among 1GHz~10GHz.
These three high frequency substrate have the following differences. Take laminate cost into consideration, among FR4, PPO and Teflon, FR4 is the cheapest one, while Teflon is the most expensive one. As to water absorption and frequency feature, Teflon is the best. When product application requires high frequency above 10GHz, only Teflon PCB substrate can be chosen to manufacture products. Though the performance of Teflon is far better than other substrate it is also more expensive and has larger heat resisting property.