Analysis of Charge Trapping and Breakdown Mechanism in High-K Dielectrics with Metal Gate Electrode Using Carrier Separation

Abstract

Using the carrier separation measurement technique, we are able to distinguish two different breakdown mechanisms: a high-K bulk initiated and an interfacial layer initiated. The results correlate with the statistical Weibull's distribution showing a polarity dependence breakdown in high-K stacks. A model of charge trapping at different spatial locations in HfAlO x with TaN gate structure is proposed to explain the polarity dependence of charge trapping characteristics and breakdown mechanisms.