Reliability study of high-κ La₂O₃/HfO₂ and HfO₂/La₂O₃ stacking layers on n-In_0.53Ga_0.47As metal–oxide–semiconductor capacitor

Abstract

This study investigates the time-dependent dielectric breakdown (TDDB) characteristics of La2O3/HfO2 and HfO2/La2O3 stacking layers on an n-In0.53Ga0.47As metal–oxide–semiconductor capacitor. Both designs improved the reliability compared with a single layer of HfO2. The TDDB followed the thermochemical E model. The current transportation mechanism changed from thermionic emission to Frenkel–Poole emission because of the traps creation under voltage stress. Both designs resulted in similar lifespans and voltage accelerating factors. However, the La2O3/HfO2 design had a longer lifespan because of the lower interface trap density and insertion of the HfO2 diffusion barrier layer between La2O3 and n-In0.53Ga0.47As. The oxide stacks exhibited excellent reliability and achieved a lifespan of 28.4 years.

Enhanced Electrical Properties of Atomic Layer Deposited LaxAlyO Thin Films with Stress Relieved Preoxide Pretreatment

“…The extension in T bd for MIS capacitor S2 was suspected to benefit from the improvement of La x Al y O/Si interface quality. On the one hand, compared with MIS capacitor S1 only treated with RCA cleaning, there should be fewer intrinsic defects nearby the La x Al y O/Si interface of MIS capacitor S2 treated with SRPO process; on the other hand, the chemical bonds of La x Al y O/Si interface formed in the thermal oxidation process of SRPO pretreatment should be more stable than those of RCA cleaning treated sample, which would decrease the probability of generating extra structural defects under the gate applied stress [35,36]. As a result, compared with MIS capacitor S1, a longer time, or a larger T bd , would be needed for accumulating defects to reach the critical point of HBD in MIS capacitor S2.…”