Properties of new printed circuit board base materials

Currently, the most widely used Printed Circuit Board (PCB) base material is the glass reinforced epoxy known as FR‐4. To improve the electrical or the thermomechanical performance of PCBs, there are two possibilities from a material standpoint: a modification or change of the resin system and a change of the reinforcement. Currently, there are a number of resins used for high performance PCB base materials. These resin systems offer higher Tgs and lower z‐axis‐expansions for improved through hole reliability. Non‐halogenated epoxy resin systems are offered for the production of green PCBs. In addition to new resins, new reinforcements are available for use in PCBs. Which can improve the electrical parameters of the base material and the x and y axis‐ thermal expansion also changes with the use of those reinforcements. This paper compares the thermomechanical and electrical parameters of some new high performance and green base materials with the glass reinforced epoxy materials commonly used in both high layer count boards and microvia applications.