Improved Charge-Trapping Characteristics of $\hbox {BaTiO}_{3}$ by Zr Doping for Nonvolatile Memory Applications

The charge-trapping characteristics of $\hbox {BaTiO}_{3}$ film with and without Zr incorporation were investigated based on $\hbox {Al}/ \hbox {Al}_{2}\hbox {O}_{3}/\hbox {BaTiO}_{3}/\hbox {SiO}_{2}/\hbox {Si}$ capacitors. Compared with the device without Zr incorporation, the one with Zr incorporation showed a similar memory window (8.3 V at $\pm$ 12 V for 1 s), but higher program speed at low gate voltage (3.2 V at $\hbox {100} \mu\hbox {s} + \hbox {6} \hbox {V}$ ) and better endurance and data retention (charge loss of 6.4% at 150 $^{\circ} \hbox {C}$ for $\hbox {10}^{4} \hbox {s}$ ), due to the Zr-doped $\hbox {BaTiO}_{3}$ exhibiting higher charge-trapping efficiency and higher density of traps with deeper energy levels.