CRYSTALLINE QUALITY AND ELECTRICAL-PROPERTIES OF PBZRXTI1-XO3 THIN-FILMS PREPARED ON SRTIO3-COVERED SI SUBSTRATES

We report the crystalline quality and electrical properties of PbZrxTi1-xO3 (PZT) films grown on Si substrates with a SrTiO3 (STO) buffer layer. STO buffer layers and PZT films were formed on Si substrates by the electron-beam assisted vacuum evaporation technique and the sol-gel technique, respectively. It is shown that by using a thin (8 nm) metal Sr layer or fluoride (SrF2, CaF2) predeposition layers prior to the STO deposition, which reduces the SiO2 layer at the Si surface, highly oriented STO and PZT thin films can he grown on Si(100) and (111) substrates. Crystalline orientation of the PZT films strongly depends on the crystalline orientation of thr STO buffer layers. It is also shown that the full width at half-maximum (FWHM) values of X-ray diffraction (XRD) peaks from PZT films are strongly related to those of STO buffer layers. Furthermore, the capacitance-voltage characteristics and current response measurements indicate the ferroelectric nature of PZT films grown on STO-covered Si substrates.