Electrical and memory window properties of Sr0.8-xBaxBi2.2Ta2-yZryO9 ferroelectric gate in metal-ferroelectric-insulator-semiconductor structure

Electrical characteristics of Sr0.8-xBaxBi2.2Ta2-yZryO9 ferroelectric films grown on HfO2/Si wafers by sol-gel spin coating technique were investigated from the viewpoint of application as ferroelectric gates in metal-ferroelectric-insulator-semiconductor (MFIS) stacks. It was observed that the leakage current density level was 10(-8) A/cm(2) under 14 V for moderate doping ratio. Determined memory windows from C-V characteristics of Sr0.8Bi2.2Ta2O9 (SBT) and Sr0.8-xBaxBi2.2Ta2-yZryO9 (x = 0.04, 0.08, 0.12 and y = 0.1, 0.2, 0.3) are 0.59, 0.65, 0.75, and 0.86 V at gate sweeping bias of 5 V, respectively. Some part of electronic properties of Sr0.8-xBaxBi2.2Ta2-yZryO9 with the objective to enhance memory window up to 45 % were discussed. It was interpreted that defects which are formed in Ba and Zr modified SBT affected the electronic processes like leakage current, memory window and charge trapping.