Characterization of Charge Trapping and Dielectric Breakdown of HfAlOx/SiON Dielectric Gate Stack

1 Introduction Hf-based silicates and aluminates showing good thermal stability [1] and favorable energy-band alignment [2] have been intensively studied as most promising alternative gate dielectrics. Despite a number of efforts to improve the dielectric properties of such high-k thin films, reliability issues such as charge trapping and dielectric wear-out are still matters of research [3, 4], especially for metal-gate/high-k dielectric gate stack. In this work, we have focused on a HfAlO x (Hf/(Hf+Al)=~0.3)/SiON stack structure and studied its temperature dependence of leakage current from Al-gate, charge trapping properties and time-dependent dielectric breakdown (TDDB).