The metal-ferroelectric-insulator-semiconductor (MFIS) structure were fabricated and investigated. The Bi 3.15 Nd 0.85 Ti 3 O 12 (BNdT) thin films were deposited on the Si substrates by sol-gel process with HfO 2 , SiO 2 and Si 3 N 4 as the buffer layers. Perovskite crystalline was obtained and the ferroelectric polarization-voltage (P-V) hysteresis was studied for the Pt/BNdT/Pt/Ti/SiO 2 /Si(100) and Pt/BNdT/HfO 2 /Si(100) capacitors. Good interfacial properties were examined between the BNdT thin film and Si substrate. Memory windows of the Pt/BNdT/HfO 2 /Si(100) structure were in the range of 0.9v-1.2v when the thickness of the HfO 2 buffer layer varied from 3 nm to 5 nm, exhibiting a considerable memory effect in the capacitors.