Step 1: Prepreg Storage and Handling
We first conduct a full engineering review of your stackup, layer structure, and manufacturing requirements to confirm process feasibility. All incoming Isola 370HR laminates and prepregs undergo strict IQC verification to ensure full compliance with specifications. Qualified materials are stored in temperature and humidity controlled environments and properly baked before production to eliminate moisture-related lamination risks.
Step 2: Innerlayer Preparation
The 370HR laminate is cleaned, imaged, and etched using standard FR-4 processes. We control dimensional movement during innerlayer processing and apply suitable artwork compensation. Bond-enhancement treatments are also used to prepare the copper surface for reliable multilayer bonding.
Step 3: Lamination
The prepared innerlayers, cores, and 370HR prepreg are stacked according to the required PCB structure. Vacuum-assisted lamination helps reduce air pockets and improve bonding. We control temperature, pressure, heating rate, and cure time based on the board thickness and layer count to achieve a stable multilayer structure.
Step 4: Precision Drilling and Desmear & Copper Plating
Precision drilling creates through-holes, vias, and other required interconnections. Drilling parameters are adjusted according to the hole diameter, board thickness, copper structure, and layer count. After drilling, the holes undergo a controlled desmear process to remove resin residue and prepare clean hole walls. Electroless copper and subsequent copper plating then build a reliable conductive layer inside the holes.
Step 5: Outer Layer Processing, Surface Finish & Testing
The outer layers are imaged, etched, and inspected to form the required circuit pattern. We carefully control trace width, spacing, and copper thickness to meet the design requirements. After solder mask and legend application, the PCB receives the specified surface finish, such as ENIG, HASL, or other compatible finishes. Final inspection may include AOI, electrical testing, impedance testing, and dimensional inspection to verify PCB quality.
