Comparison of Degradation and Recovery of SiONx and Hf-Based Dielectric under Electrical-Field Stress

Abstract

Using the electrical-field (E-field) stress at the positive and negative directions to generate the degradation and form the recovery effect is a useful metrology to evaluate the integrity of gate dielectric. This consequence deeply influences the drive current of 2D MOSFET or 3D FinFET species. According to the experimental results with the short and long-term stresses, we found the electrical performance of Hf-based tested devices represented the better recovery than that of SiON-based ones. And the recovery effect is more regular, not only in VT shift, but in gate leakage due to the high-k dielectric probably providing the polar effect and more trap assistants.