Radiation Effects on FR4 Printed Circuit Boards

This article presents measurements of electrical and physical properties for a variety of FR4 fiberglass-reinforced resin laminates, and the respective changes following exposure to a 1.9 × 10 ¹⁶ n/cm ² total neutron fluence. The selection of a printed circuit board (PCB) substrate is shown to be of consideration beyond the typical frequency-dependent parameters, specifically for high fluence radiation environments where small changes to the dielectric constant are of concern.