The thermal stability of pure HfO2 thin films is not high enough to withstand thermal processes, such as S/D activation or post-metal annealing, in modern industrial CMOS production. In addition, plasma nitridation technology has been employed for increasing the dielectric constant of silicon dioxide and preventing boron penetration. In this experiment, atomic layer deposition (ALD) technology was used to deposit HfO2 thin films and inductively coupled plasma (ICP) technology was used to perform plasma nitridation process. The C-V and J-V characteristics of the nitrided samples were observed to estimate the effect of the nitridation process. According to this study, plasma nitridation process would be an effective method to improve the thermal stability of HfO2 thin films. (C) 2008 Elsevier B. V. All rights reserved.