Published online by Cambridge University Press: 01 February 2011
The assessment of the thermal stability across HfO2/Si and HfO2/SiO2 interfaces has been difficult due to lack of thermodynamic data. In this paper, we present the results of thermodynamic calculations intended to fill this gap. A thermodynamic model was developed by assuming that HfSiO4 is an ideal solution of HfO2 and SiO2 to a first order approximation. The theoretical results predict that the HfO2/Si interface is thermodynamically stable up to 1100°C, while the HfO2/SiO2 interface is thermodynamically unstable even at room temperature. Our experimental results from TEM and XPS analysis are consistent with these modeling predictions.