As water is to humans, Printed Circuit Boards is to electronic devices and gadgets. In the world surrounded with technological devices, cell phones, Televisions, computers and thousands of other devises, the presence of PCBs is simply inescapable. It is due to such significance and vitality of PCBs that its design and manufacturing process has become exceptionally advanced and sophisticated in the recent years. Engineering designs and technology have been trying to decrease the size of printed circuit boards while increasing their component density and the complexity of operations performed. This intent of scientists has lead to several fabrication and assembly procedures which incorporate advance engineering drawings and mechanism so to make the devices as compact as possible by reducing the width and length of the printed circuit board.
The first PCB design was single-layered and this design is still used at beginners’ level and for simple circuits. The term single-layered is coined on the conducting property of the PCB on only one side of the wafer. Copper is coated on one side of the wafer (board) and this side is called the conducting layer. As there is only one conducting layer, components can only be placed at single side of the board, and therefore the length and width of the board is directly proportional to the number of components; resistors, transistors, capacitors and other electronic components.
The design of double-layered board was later developed which gave profound power and sophistication to the PCB design. With copper coated on both sides of the wafer, the board can now fabricate up to two times the components as they were in the single layered board. A glass insulating layer is placed in between the two layers so that the conducting lines are not short circuited and current can flow smoothly from both sides of the board. The complexity of design however augments, and for this reason double-layered PCBs are mostly machine designed and cannot be manually fabricated like the single layered boards.
Scientists and engineers have always had quest for more advancement and more betterment in the existing technology and keep striving for achieving new heights of technological sophistication and power. This strive for more and the desire for further improvement led to the invention of multi-layered PCB designs which are more powerful and are used in all complicated engineering designs today. The latest cell phone models in the market perform messaging and texting operations, have games installed in it, can connect to the internet and have hundreds and thousands of other functions built-in. all these functions and applications require different software and hardware logic and a unique circuitry for their operation. Integrating these hundreds and thousands of circuits into a single devise is the power of multi- layered PCB fabrication. This is not just confined to cell phones but to each and every engineering gadget that has been innovated in the last three to four decades. In the multi-layered PCBs, each layer is so finely attached with the upper layer that the conducting lines are thick enough to carry sufficient current for operation and thin enough to not intertwine with any other conducting point in any of the multiple layers. With the development of multi-layered technology for PCB fabrication, engineering marvels reached to a new height of design perfection and excellence.