Printed Circuit Boards (PCB) are those circuits which electronically connect the various electronic components and give them mechanical support by using some conductive paths and tracks. It offers great reliability and is also highly cost effectiveness as compared with other circuits such as wire wrapped circuits or point to point circuits. Actually PCB supports the electronic devices mechanically and builds a mechanical connection between them using conductive paths, copper etched traces and etched wiring. Although the initial cost is very high for the complicated manufacturing processes but it gives you really reliable high performance.
Actually there are mainly three methods which are used by the producers of PCB which also divides into subtractive methods. In this process, copper layer is created on both or either side of a substrate. And after this, the undesired excess copper is removed and the required copper retains as there is temporary mask.
The conduit layer of copper with laminated overlay is used to comprise the PCB. Epoxy resin mainly builds the laminated cover of the board which is just like some kind of hard plastic. This resin has green color for which the board also looks green which is actually an epoxy of green color. But it can also get other colors by using other types of materials in laminating. This may be cotton paper with epoxy is also known as woven glass mixed with epoxy. But the standard product that is usually used in creating PCB is the thin copper layer with green mask epoxy. There also some unwanted copper on the substrate which needs to be removed. And the following process does this.
Photo Engraving is one of the most common processes used by the manufactures. In this process, the undesired copper is removed by chemical etching or photo mask process. This process works with photo plotter which is created by the technicians using computer software.
Silk Screen printing is another of the processes. This method includes etchresistant ink which protects the required copper foils and removes the unwanted copper.
PCB Milling uses plotter and commands of software to remove the unwanted copper from the substrate.
Lamination is another process which involves multilayer circuits. In it, multiple bonding of these layers is created so that it can protect the required copper and remove the unwanted one.
Drilling technique is used by a drilling machine which is operated by automated computer software and connects the layers of PCB with each other by creating some holes known as VIAS.
These companies also work on custom PCBs which are made especially depending on the customer's order and specification. Here they first make a PCB Prototype upon which they perform all their necessary experiments. They first make the design and then make a PCB Prototype. Then it is tested and again tested for examining that whether it is fulfilling the required specifications or not. Also its functionality and reliability are checked carefully. Only after the all experiments, it is then send for the manufacturing process.
This way the PCB circuits are created and manufactured for the use of the customers.
