FABRICATION OF PBZRXTI1-XO3 FILMS ON SI STRUCTURES USING Y2O3 BUFFER LAYERS

Lead-zirconate-titanate (PbZrxTi1-xO3:PZT) films were epitaxially grow n on Si(lll)substrates using Y2O3 buffer layers. Y2O3 layers were prep ared in a molecular beam epitaxy (MBE) apparatus with a single electro n beam gun, while PZT films were prepared in a vacuum evaporation cham ber with both a crucible and an electron beam gun. It was found from i n situ RHEED observation that Y2O3 layers grew epitaxially on Si(lll) substrates. It was also found from X-ray diffraction analysis that str ongly (101)-oriented PZT films grew on the Y2O3/Si(111) structures at a substrate temperature of 700 degrees C. Metal-ferroelectric-insulato r-semiconductor(MFIS) capacitors were fabricated using this structure, and capacitance-voltage (C-V) curves showed a memory window of about 2.6 V, which is considered to be due to the ferroelectric nature of th e PZT film.