Passivation Properties of Atomic-Layer-Deposited Hafnium and Aluminum Oxides on Si Surfaces

This paper studies the chemical and field effect passivation properties of silicon surfaces by thin hafnium oxide (HfO2) and aluminum oxide (Al2O3) layers grown by chemical-vapor-based atomic layer deposition method. Using a rigorous metal-oxide-semiconductor model and results from capacitance-voltage measurements, the density of fixed charges (N-f) and the density of interface traps (D-it) at the HfO2/Si and Al2O3/Si interfaces were obtained. Microwave photoconductivity decay measurements were used to characterize interface recombination velocities at these interfaces.