Abstract
The electric properties of ferroelectric BiFe O3 (BFO) thin films with Zr O2 insulating buffer on Si substrates fabricated by chemical solution deposition were investigated. Zr O2 demonstrates excellent insulating properties on Si substrates. The metal-ferroelectric-insulator-semiconductor (MFIS) structure exhibits clockwise capacitance-voltage hysteresis loops due to the ferroelectric polarization of BFO. The maximum memory windows are 0.66 and 0.78 V, respectively, for BFO deposited on postannealed Zr O2 and on unannealed Zr O2 insulating layers. The small memory window of the BFOZr O2 (postannealed) MFIS is caused by significant interface trap states on the BFOZr O2 interface; this is supported by C-V measurements under varying frequency. © 2007 American Institute of Physics.