Material Selection – Choosing a substrate material like FR4 serves as the base for the two copper layers.

Layer Lamination – Applying copper foil to both sides of the substrate and bonding it with heat and pressure.

Drilling & Plating – Drilling holes for vias and plating them with copper to create electrical connections between layers.

Etching & Imaging – Etching the copper to form circuit patterns on both sides, using photolithography for precision.

Surface Treatment – Applying surface finishes like HASL, ENIG, or OSP to improve solderability and corrosion resistance.

Testing & Inspection – Conducting electrical and mechanical testing to ensure functionality and quality.