Back in 1936, the first printed circuit board (PCB) was created by Paul Eisle. But it was not until the 1950s once the U.S. Defense industry began integrating PCBs within their bomb detonator approaches that printed circuit boards found wide application. PCBs are now utilised in the majority of manufactured products like, automobiles, mobile phones, computers, among others.
A Summary of the PCB Fabrication Processes
PCBs are initially fabricated by means PCB prototype of two kinds of software. Computer Aided Design (CAD) applications is applied to design the electronic schematic of the circuit to be produced.
Once the PCB prototype is designed, the initial step into the fabrication procedure is to choose the material of this printed circuit board.
After the material has been selected, the first process is to apply a coat of copper to the entire board. The circuit layout is then going to be printed onto the board by a photo sensitive process. Afterward, a photograph prototyping process will be used to ensure all of the copper that isn’t part of the circuit layout is going to be etched outside or removed from the board. The resulting copper creates the traces or tracks of the PCB circuit. To join the circuit traces, two processes are all used. A mechanical grinding process will use CNC machines to remove the unnecessary copper from the board. Subsequently, an etch-resistant, silkscreen, printing process is applied to pay the regions at which traces must exist.
At this point in the PCB fabrication process, that the PCB board contains copper traces without any circuit components. To mount the components, holes must be drilled at the points where the electrical and electronic equipment parts are set on the plank. The holes are drilled using lasers or a distinctive kind of drill piece made from Tungsten Carbide. Once the holes have been drilled, then hollow rivets are inserted to them or they’re coated by an electroplating process, which creates the electrical connection between the layers of the board. A masking material is subsequently employed to coat the entire PCB with the exclusion of the pads and the holes. There are many types of masking material such as, lead solder, lead free solder, OSP (Entek), deep/hard gold (electrolytic nickel gold), immersion gold (electroless nickel stone – ENIG), wire bondable gold (99.99% pure gold), immersion silver, flash stone, immersion tin (white tin), carbon peroxide, along with SN 100CL, an alloy of tin, aluminum nickel. The final step from the PCB fabrication process is to screen print the board therefore labels and the legend appear at their proper locations.
Testing the Quality of the PCB Board
Prior to setting the electric and electronic components on the PCB, the plank needs to be analyzed to verify its functionality. Generally, there are two kinds of malfunctions that can cause a faulty PCB: a short or an open. A”short” is really a link between two or more circuit points that should not exist. An”open” is really a point where a connection should exist but will not. These flaws have to be fixed before the PCB is constructed. Regrettably, a few PCB manufacturers tend not to examine their boards until they are shipped, that may lead to issues at the customer’s location. So, quality testing is a crucial procedure of this PCB fabrication process. Testing ensures that the PCB boards come in proper working condition before component positioning.