An investigation of capacitance aging model for extreme low-k and high-k dielectrics

Abstract

In this paper, Power Law model as a function of voltage is proposed as a new lifetime model to quantify the capacitance drift for Extreme Low-k (ELK) and High-k (HK) dielectrics. We experimentally proved that charge trapping/ detrapping governed the capacitance drift for both ELK and HK based on the capacitance aging and the conduction mechanism analysis. Through the trapping charge recovery study, the capacitance drift can be improved by eliminating the positive or negative charges during process. We also noted that new dipoles generated by trapped charges under stress is higher in HK than ELK, which results in not only more obvious capacitance drift but also stronger correlation between capacitance drift and capacitor breakdown in HK films.