Leakage current degradation and carrier conduction mechanisms for Cu/BCB damascene process under bias-temperature stress

In this study, the leakage current degradation and conduction mechanisms for the Cu-BCB damascene process module under bias-temperature stress were investigated in detail. New carrier conduction and leakage current failure mechanisms were uncovered. The space charge limited current was found to be a dominant leakage current mechanism. Models were proposed to explain the anomalous leakage currents observed with high and low bias field stresses. We believe that the results obtained in this study can be equally applicable to any Cu-low k dielectric material combination.