Fabrication and characterization of MFIS-FET using Bi_3.25La _0.75Ti₃O₁₂/ZrO₂/Si structure

A metal-ferroelectric-insulator-semiconductor structure (MFIS) has been fabricated by Zro₂and Bi_3.25La_0.75Ti ₃o₁₂ as the buffer layer and ferroelectric film in forming MFIS diodes on Si(100) substrates, respectively. Zro₂ films were prepared by a sol-gel method. Then, they were carried out dry o₂ annealing in a rapid thermal annealing (RTA) furnace at 700°C for 10 min. On the ZrOj/Si structures, Bi_3.25 La_0.74TiI ₃O₁₂ films were deposited by sol-gel method and they crystallized rapid thermal annealing in O₂ atmosphere at 750°C for 30 min. They were characterized by X-ray diffraction analysis (XRD) and atomic force microscopy (AFM). The memory window width in capacitance-voItage(C- V) curve of the Au/BLT/ZrO₂/Si diode was about 1.0 V for a voltage sweep of ±4 V. Base on these results, we fabricated the MFIS-FET structure. The memory window width in drain current-gate voltage (I _D-V_G) curve of the MFIS-FET was about 0.7 V.