Improvement on Electrical Characteristics of HfO2 MIS Capacitor with Dual Plasma Treatment

Abstract

There have been some researches described that nitridation processes could improve thermal stability and dielectric constant of Hf-based dielectrics. The improvement of electrical characteristics of HfO2 thin films with plasma nitridation has been examined. Moreover, CF4 plasma treatment on HfO2 thin films in order to suppress leakage current and passivate defect were also proposed. In this study, we proposed to combine two kinds of plasma treatment, CF4 pre-treatment and nitrogen post-treatment, in order to have further improvement on electrical characteristics. The capacitance-voltage (C-V) characteristics, current-voltage (J-V) characteristics, and hysteresis of the samples were preformed to estimate the improvement effect. According to this study, dual plasma treatment would be an effective technology to improve the electrical characteristic and the hysteresis of pure HfO2 thin films.