Investigation of electrical properties of HfO2 metal-insulator-metal (MIM) devices

This paper is devoted to the study of the electrical properties of Au/HfO2/TiN metal-insulator-metal (MIM) capacitors in three distinctive modes: (1) alternative mode (C-f), (2) dynamic regime [thermally stimulated currents, TSCs I(T)] and (3) static mode [I(V)]. The electrical parameters are investigated for different temperatures. It is found that capacitance frequency C-f characteristic possesses a low-frequency dispersion that arises for high temperature (T > 300 A degrees C). Accordingly, the loss factor exhibits a dielectric relaxation (with an activation energy E (a) 1.13 eV) which is intrinsically related to the diffusion of oxygen vacancies. The relaxation mechanisms of electrical defects in a dynamic regime (TSCs) analysis show that defect related to the TSC peak observed at 148.5 A degrees C (E (a) 1 eV) is in agreement with impedance spectroscopy (C-f). On the other hand, when the MIM structures are analyzed in static mode, the I-V plots are governed by Schottky emission. The extrapolation of the curve at zero field gives a barrier height of 1.7 eV.