serigraphy or silkscreen for short, is done on the top layer of the PCB and has the role of a reference indicator for the components on the PCB. Graphics and text on a circuit board's PCB are usually printed with a pcb design non-conductive permanent epoxy ink. The color is usually white, although other colors are available:
signal traffic in printed circuits, when the tracks carry signals at high frequencies, great care pcb design must be taken in designing the tracks to match the impedance of the upstream and downstream components. The longer the route or the higher the frequency, the better adaptation is required. When producing the printed circuit with controlled impedance, the
varnish on the entire surface of the printed circuit less on the soldering pads and it also has a pcb design role of antioxidation of the copper traces. Being a substance with a high degree of electrical insulation, the soldering mask offers the printed circuit the possibility of having a high density of components.