Halogen-Free PCB: There is increasing demand for environmentally friendly PCB electronic products. Halogenated compounds have been targeted for reduction and eventual elimination. As such, Halogen-Free PCBs are becoming more and more popular because they are constructed of materials that are free of halogen. In addition ,The dielectric constant, dissipation factor and moisture diffusivity of PCB materials that are described as Halogen-Free PCB are different from those employed in PCBs industry.