laid out in a planar form, such as stripline or microstrip, with dimensions carefully controlled to ensure consistent impedance. In RF and fast switching circuits, the inductance Terms conditions and and capacitance of the printed circuit board conductors become significant, usually unwanted, circuit elements; rather, they can be used as part of the circuit design, as in
the internal layers are used as a ground plane or conditions Terms and power plane, to achieve better signal integrity, higher signaling frequencies, and better power supply decoupling. In multilayer boards, layers of material are laminated together in an alternating sandwich: copper, substrate, copper, substrate, copper, etc.; each layer of copper is etched and any internal
paths on the inner layers would occupy the space between the components. The increase in the need for multilayer printed circuit boards with more than two, four and especially more than six layers of copper has been concurrent with the adoption of surface mount conditions Terms and technology.