The printed circuit board, or PCB for short, is one of the most important components in the world of electronics today. Without PCB fabrication, typical electronic products such as televisions, air conditioners, and computers would have sizes as big as a typical personal room in a house due to the many complicated wires and enormous circuits needed for them to run smoothly and efficiently.
A PCB is defined as an electronic circuit board that is composed of a thick base layer and a thin layer made of copper foil in which the circuitry is made via etching. It is where electronic components such as transistors are later mounted via a process called soldering before the board is actually used. The base layer is called the substrate; and is made of any of the following materials, regardless if they are rigid or flexible: hard plastic, phenolic, masonite, glass, and fiberglass.
PCB fabrication began in 1940 when Paul Eisler of Vienna, Austria wanted to simplify the manufacturing of radio circuitry. In Eisler’s time, wires thicker than coaxial cables and transistors as big as light bulbs were the norm in electronics. The very first generations of computers employed those colossal wires and transistors, creating convoluted circuits with sizes equaling those of usual offices today.
Eisler’s conception became widespread after World War II due to three reasons: reliability, space-saving potential, and the plausibility of mass production. Electronic devices using PCBs became smaller and more compact, easier to service due to the copper foil replacing the wires, and opened the doors for the eventual commercialization of electronics in general. In 1957, the first commercial computer that used transistors made use of PCBs, which had those transistors and other components soldered on them.
As the quest for compactness still continued, even the already compact PCB had to shrink even further. Enter the integrated circuit or IC for short. It was developed by Jack Kilby of Texas Instruments and is usually made of silicon. Whereas the PCB uses copper as a conductor for the electricity to power its molded components, the IC uses a process in which the flow of electricity is dictated whether the silicon touches an impure substance or not. The combination of silicon and the impure substance is called the semiconductor, and an IC is basically one. ICs are usually smaller than the fingers of a human hand and are vital in devices such as smartphones, MP3 players, and the central processors of a typical modern PC. However, due to their roles in resisting the flow of electricity and storing it, resistors and capacitors cannot be shrunk to IC-level sizes, respectively.
The creation of a compact electronic circuit does not stop with PCB fabrication. For a PCB to be put into good use, the required components must first be mounted onto the board using a process called soldering. Soldering is the process of connecting metal parts the electronic way using a filler metal, which is called the solder. The solder is melted using a soldering iron with temperatures ranging from 300 degrees Celsius to 427 degrees Celsius to form a kind of glue that binds the PCB’s copper foil and the components’ terminals together.
PCBs and their components are not the only things that can be joined together via soldering. Wires and cables can also be soldered together. The insulating coatings must be removed and the inner conductors must be bunched together before the solder can be applied.
Together, PCB fabrication and IC fabrication go hand-in-hand to serve as building blocks of the many electronics humanity enjoys today and will continue to enjoy for the years to come.
PCB fabrication is all about the assembly of circuit boards used in electronics and computers. The layers of PCBs are assembled along with their specific surface patterns in order for them to be used in manufacturing electronics.