The ADRF5721-EVALZ is a 4-layer evaluation board. The top and bottom copper layers are 2.2 mil (1.5oz) and are separated by dielectric materials.
All RF and dc traces are routed on the top copper layer whereas the inner and bottom layers are grounded planes that provide a solid ground for the RF transmission lines. Top dielectric material is 12 mil Rogers RO4003, offering optimal high frequency performance. The middle and bottom dielectric materials provide mechanical strength. The overall board thickness is 62 mil, which allows 2.4 mm RF launchers to be connected at the board edges.