Critical Temperature to Dielectric Degradation of Printed Circuit Board

Dielectric degradation of printed circuit board based on the thermal properties in an open-air environment was investigated. With increase of the temperature, the copper electrodes were oxidized from Cu2O to CuO; the base material of epoxy laminate was thermally affected to the change of molecular structure and degradation of dielectric prorperties. With increase of the temperature, the capacitance and surface resistance decreased, the thermal stimulated current increased and showed a valley value near 450 K and a peak value near 490 K.