Abstract: This paper studies the signal crosstalk due to redundant object defect of adjacent copper interconnects. The models of coupling capacitance and mutual inductance between redundant defect and interconnects are presented, and it can be used to quantitatively calculate the influence of defect on crosstalk. In the experiment model, defect is regard as a separate section RLC circuit. Signal crosstalk is studied under the conditions that are various parameters of interconnect using the model. The far crosstalk and near crosstalk of the copper interconnects are studied. Finally, some advice improved signal crosstalk is put forward. Experiment results show that the presented model can be used actual circuit design, and can guide designer to design circuit for satisfying crosstalk requirements.