Charge Trapping in HfYOx Gate Dielectrics on Strained-Si

Abstract

HfYOx gate dielectric has been deposited on strained-Si/Si0.8Ge0.2 by RF co-sputtering of HfO2 and Y2O3 targets. Chemical and electrical properties have been demonstrated by x-ray photo electron spectroscopy (XPS), capacitance-voltage (C-V) and leakage current (I-V) characteristics. The reliability characteristics of HfYOx gate dielectric stacks on strained-Si/Si0.8Ge0.2 have been investigated under different field (2.3-6MV/cm) and constant current stress (10-25mA/cm2) of different amplitude and fluence in order to analyze the degradation of oxide as a function of stress parameters. Oxide trap charge and trap centroid location have been analyzed after constant current stressing.