What is Desmear

What is Desmear

Desmear is a process in the production of PCBs that involves the removal of drilling debris and friction-melted resin from the drilled holes. After the drilling of the PCBs, residues of the board material tend to remain at the edges of the holes, which can negatively impact the circuit’s reliability and performance. Desmear is carried out using various methods, such as permanganate or plasma treatment.

Plasma desmear, for instance, utilizes controlled chemical reactions to effectively clean the epoxy resin from the inside of the drilled holes, ensuring their cleanliness and promoting good electrical contact between the interconnects and the copper through-plating. This process is particularly important in maintaining circuit reliability and preventing any potential issues caused by poor electrical connections.

In addition to removing the residue, certain desmear processes can also enhance the adhesion of the resin coating by micro roughening the surface. This micro roughening improves the coating’s ability to adhere to the PCB, further enhancing the overall quality and performance of the circuit board.