Theoretical and Experimental Studies on Retention Characteristics of Metal-Ferroelectric-Insulator-Semiconductor and Metal-Insulator -Ferroelectric-Insulator-Semiconductor Structures

摘要

Retention characteristics of Metal-Ferroelectric-Insulator-Semiconductor(MFIS) and Metal-Insulator-Ferroelectric-Insulator-Semiconductor(M-I-FIS) structures have been investigated both theoretically and experimentally. The simulated time dependence of capacitance for the MFIS has indicated that reducing currents through the ferroelectric and the insulator layers improves the retention characteristics more effectively than choosing the insulators with larger dielectric constants. The M-I-FIS structure has been studied in order to reduce the charge injection between the metal and the ferroelectric layer in the MFIS. The simulations have indicated that the M-I-FIS can provide much longer retention time than the original MFIS, although the experimental retention time of the M-I-FIS have almost the same as that of the MFIS.