A new method on Cu stress measurement by bandgap voltage reference circuit

Cu metallization is not only used in low power logic circuit but also in high power automotive application because of its low resistance and robustness in repetitive clamping. How to characterize the stress in Cu metallization is a crucial issue in BEOL integration scheme. In this paper we design a circuit with bandgap reference voltage and overVoltage capability which are able characterize the correlation of Cu stress and in line wafer bow through electrical measurement.