PCBs are the heart and brain of electronic devices today, whether the devices belong to the entertainment industry, automotive industry, medical industry, or any other trade. This is why it is advisable to approach only expert professionals offering the best Electronics ManufacturingServices in India to help you get the most suitable PCBs for your industry and application.
No matter what the industry and application, there are a multitude of tiny components assembled onto a single board, such as resistors, transistors, capacitators, inductors, diodes, switches, batteries, LEDs, and more, each connected with copper traces to supply electrical charge from one point to another. With such a complicated structure on such a tiny board, you can imagine the minuteness of each component and connection. But, can you imagine how difficult and challenging it can be to clean each component and connection on such a tiny board!? Yet, it is important to clean the PCB thoroughly because without clean components and clean connections, the electronic devices into which the PCBs are installed won’t work the way they are required to. Cleaning the PCB right is important to improve its overall reliability, performance, effectiveness, durability, and life.
How can PCBs be cleaned?
PCBs are generally soiled with flux, solder, dust, moisture, fingerprints, residues, etc. There could be some contaminates that possess erosive properties, leading to damage of circuits and connections, thus causing shorts and failures, shortening the lifespan of the device. Cleaning away all such debris can ensure zero faults in functionality, and prolong the life of the device. When cleaning PCB assemblies, the main goal is to remove resin and flux residues. There are a number of ways to do this, each process having its own pros and cons. There is a manual cleaning method, an ultrasonic cleaning method, and a gas phase cleaning method. The cleaning method you choose from these depends upon the effectiveness, complexity, and density of components on the board. Other factors that determine the cleaning method to be used include the number of boards, equipment available, environmental impact, time available, and the costs incurred.
Manual cleaning method
This type of cleaning method involves removing the leftover solder material and contaminates manually with the help of alcohol solution and a small brush. First, the PCB is soaked in acetone solution for 10 minutes to loosen any contaminates or dirt on the board. Then, a brush soaked in ethyl alcohol solution is used to gently remove unwanted particles, after which the board is rinsed in demineralized water for a few minutes, and then finally dried using a nitrogen gas gun. Since the method is so simple, and doesn’t involve any special tools, it is comparatively affordable. Also, it is less toxic to both people and the environment. However, because the process is manual, it is also time-consuming, which is why it is not preferred for large batches of boards. Moreover, it is difficult to clean dense boards with the manual method, because this method limits cleaning only to the areas that can be reached with the brush.
Ultrasonic cleaning method
This method involves using a special machine. But first, in this method too, the board is soaked in ethyl alcohol solution to loosed the dirt or contaminates. Then, it is placed into the bath of cleaning solution inside the ultrasonic cleaner, which emits high-frequency sound waves into the liquid, creating billions of tiny bubbles that pop and physically remove any possible contaminates on the board. This method proves to be a very good option for cleaning dense boards, because the tiny bubbles are capable of reaching every bit of the exposed surface, even the smallest and most hard-to-reach places.
Gas phase cleaning method
This method involves boiling a chemical solvent to create steam, which dissolves the dirt and contaminates left on the board. This method is as effective as the ultrasonic cleaning method, but is comparatively more environment-friendly, because the solvent used is generally reusable after filtering the impurities. This is why this cleaning method is also preferred for cleaning dense PCBs.