Effect of post-deposition annealing on charge distribution of metal-oxide-semiconductor capacitor with TiN/HfO2/SiO2/Si gate structure

We experimentally investigate the effect of post-deposition annealing on the charge distribution of a metal-oxide-semiconductor capacitor with a TiN/HfO2/SiO2/Si gate structure. We decoupled interfacial charges at the SiO2/Si and HfO2/SiO2 interfaces; bulk charges in HfO2; and the dipole formation at the HfO2/SiO2 interface. The interfacial charges at the HfO2/SiO2 interface decreased and the dipole increased after H2 or N2 annealing. Oxygen dangling bonds are the physical origin of the charges at the HfO2/SiO2 interface. The interfacial charges at the SiO2/Si interface and the bulk charges in HfO2 are almost unchanged.