composition

The current board, mainly consisting of
Line and drawing (Pattern): lines are used as tools conduction between the original, the design will also devise a large copper surface as the ground and power planes. Line and drawing are made simultaneously.
The dielectric layer (Dielectric): used to hold the line and insulation between the layers, known as the substrate.
Hole (Through hole / via): vias allow two or more lines each level conduction, larger vias are used as a plug-in parts, and another non-conductive vias (nPTH) usually used as surface mount loaded position, when assembled with the mounting screws.
Solder Mask (Solder resistant / Solder Mask): not all have to eat tin on copper surface parts, so the non-eating tin region, will be printed eat tin copper surface layer of isolation material (usually an epoxy resin), avoid Non-food tin between short-circuit. Depending on the process, into green oil, oil, oil blue.
Screen (Legend / Marking / Silk screen): This non-necessary structure, main function is labeled on the board the names of the parts of the Location box, easy assembly after maintenance and Identification of.
Surface treatment (Surface Finish): Due to the copper surface in the general environment, it is easily oxidized, resulting in not on the tin (solder adverse), and therefore protected eat tin in copper surface. There are ways to protect HAL (HASL), and gold (ENIG), silver (Immersion Silver), tin (Immersion Tin), organic solderability preservative (OSP), methods have advantages and disadvantages, collectively referred to as surface treatment.