A high frequency printed circuit board, whether it’s rigid or flex, offers faster signal flow rates and a frequency range of up to 100 GHz. It’s important to note that there are numerous materials designed to operate at high frequency levels. HF PCBs are defined by lower dielectric constant (Dk), lower dissipation factor (Df), and low levels of thermal expansion. They are used regularly for HDI technology. They are also used extensively in high speed communications, telecommunications, and RF microwave technology.