Optical and electrical characterization of hafnium oxide deposited by MOCVD
Abstract The paper reports on electrical and optical investigations performed on HfO 2 high- k films deposited by Metal-organic chemical vapor deposition (MOCVD). Spectroellipsometry investigations show the presence of a transition layer between HfO 2 and the silicon substrate, which can be optically modelled as a mixture of Si and SiO 2 ; this information is further used in the assessment of the electrical measurements. Hysteresis effects have been observed in the Capacitance–Voltage ( C – V ) measurements for the as-deposited sample as well as the annealed samples. For the samples with large hysteresis, Poole–Frenkel (PF) conduction is the most likely dominant conduction mechanism. The energy of dominant trap level was found to be ∼0.7 eV.