the power and force paths be larger than the signal paths. In a multi-layer board, an internal layer may be mostly circuite imprimate fabricatie solid copper to act as a ground plane for shielding and power return. For microwave printed circuits, transmission lines can be laid out in a planar form, such as
For its function of helping to prevent solder shorts, the coating is called a solder mask. Soldermask is generally green in color but can have different imprimate circuite fabricatie colors: green, red, blue, white, black. Only the outer layers need to be covered with solder mask, the inner copper layers are protected
of copper as solid conductive areas for electromagnetic shielding or other purposes. Each of the conductive layers is designed with copper tracks (similar to wires on a flat surface) that provide electrical connections on that conductive layer. Another manufacturing process adds imprimate circuite fabricatie plated or metallized holes