Characterization of metal-ferroelectric-(metal-)insulator-Semiconductor (MF(M)IS) structures using (Pb, La)(Zr, Ti)O-3 and Y2O3 films

Metal-ferroelectric-(metal-)insulator-semiconductor (MF(M)IS) structures ar e fabricated and characterized using (Pb,La)(Zr0.3Ti0.7)O-3 (PLZT) and Y2O3 films. Y2O3 buffer layers are epitaxially grown on Si(111) substrates by m olecular beam epitaxy and ferroelectric PLZT films are formed on (Pt/)Y2O3/ Si by the sol-gel technique. It was found that the Al/Y2O3/Si MIS structure has a low leakage current of less than 10(-8) A/cm(2). The capacitance-vol tage (C-V) characteristics of the PLZT/Y2O9/Si MFIS structure exhibit a hys teresis loop due to the ferroelectricity of the PLZT film with a memory win dow of 1 V. On the other hand, the memory window of the Pt/PLZT/Pt/Y2O3/Si MFMIS structures is significantly improved.