A major cause of problems in multi-layer PCBs is which of the following?

A major cause of problems in multi-layer PCBs is which of the following?

• A. Age
• B. Corrosion
• C. Interlayer separation
• D. Overheating

Answer: (C)

Interlayer separation (delamination) between the bonded layers is the major failure mode in multi-layer PCBs because the stack relies on a solid, continuous bond to keep all layers mechanically aligned and electrically connected. When the layers separate, voids form, copper traces can lift or crack, vias can lose connection, and impedance paths change. This directly disrupts circuits across multiple layers and undermines signal integrity and reliability. Thermal cycling, moisture, and manufacturing defects can drive delamination, making it the most impactful and common problem in multi-layer boards. While aging, corrosion, or overheating can cause issues, they don’t as directly threaten the interconnected, multi-layer structure in the way interlayer separation does.

Interlayer separation (delamination) between the bonded layers is the major failure mode in multi-layer PCBs because the stack relies on a solid, continuous bond to keep all layers mechanically aligned and electrically connected. When the layers separate, voids form, copper traces can lift or crack, vias can lose connection, and impedance paths change. This directly disrupts circuits across multiple layers and undermines signal integrity and reliability. Thermal cycling, moisture, and manufacturing defects can drive delamination, making it the most impactful and common problem in multi-layer boards. While aging, corrosion, or overheating can cause issues, they don’t as directly threaten the interconnected, multi-layer structure in the way interlayer separation does.