Printed circuit board assemblies are the souls of any electronic device that allow it to function. Therefore, it is important to protect PCBs from any dirt and contamination caused by foreign substances as well as remaining particles of copper as that may damage them. Plating PCBs is an ideal process used for protecting printed circuit boards from oxidation, damage, moisture, and so on. The plating method involves the deposition of a thin metal layer, mostly copper, on the PCB surface area. This deposited layer creates a shield that protects the PCB from contamination and gives it a smooth soldering surface for assembling the components. Are you intrigued to learn more about PCB plating? If yes, you are on the right page. This post introduces you to different types of PCB plating methods and the importance of plating methods for PCB manufacturing.

Types of PCB Plating Methods

PCB plating is an important part of the manufacturing and assembling process. It is done differently for surface finishes and vias because of obvious reasons. The types of plating methods used for PCB assemblies are as follows:

Via Plating: A via is an electrical connection that plays the role of a bridge between different layers of a PCB. Via plating involves drilling and filling of copper to provide a road for the current to pass from one layer to another. Via plating needs to be done considering all the holes and wiring. Primarily, there are three types of vias plating techniques.

• Through-Hole Via Plating: This plating method is an electroless plating method that involves drilling through copper foils. Through-hole plating process forms conducive inner walls which easily connect to the printed circuit boards.
• Blind Via Plating: A blind via is made through a drilling process that connects two or more inner layers to one of the outer layers. Blind vias are plated using metal through-hole connections. In addition, various components like copper sulfate, sulfuric acid, and so on are added to the plating solution for an advanced finish of the PCB layers.
• Buried Via Plating: Buried vias are constructed to build a connection between inner layers without reaching the outer layer. As the name suggests, buried vias remain within the inner layers and are not visible from the outer layers. These vias are plated through a combined process of chemical and mechanical abrasion, which involves a coating of a thin copper layer known as an electroless copper deposition.

Surface Plating: Surface plating, also referred to as surface finishing, is a process used for covering copper traces to prevent them from moisture, oxidation, dust, contamination, and so on. The following are some popular types of PCB surface plating methods.

• Hot Air Solder Levelling: HASL is one of the most successful processes used for PCB surface finishing. In this method, a printed circuit board is submerged in molten solder, which covers exposed copper surfaces.
• Electroplating: In this plating process, DC current is generated for the deposition of metal on copper traces. The most commonly used metals for electroplating are tin, gold, and nickel.
• Immersion Plating: It is an RoHS-compliant process and does not require electricity for plating. The tin coating is done on the PCB surface to protect it from oxidation, thus increasing its shelf-life.

After reading the above information, you may be able to decide on the right PCB plating method for your printed circuit boards. But along with a good piece of information, it is crucial to consult a trusted PCB manufacturer and assembly services provider. Ensure you partner with a service provider that has experience in your industry segment and can offer custom PCBAs. Rigiflex Technology Inc. is a certified PCB manufacturer and assembler of PCBs and one of the top players when it comes to custom PCB manufacturing. The company manufactures various types of printed circuit boards of superior quality. Moreover, they use different PCB plating methods for PCB manufacturing. In case you have any queries, you can get in touch with the team at Rigiflex Technology Inc. today.