EFFECT OF BISMUTH ON THE FERROELECTRIC PROPERTIES OF SRBI2TA2O9 THIN-FILMS DEPOSITED ON PT SIO2/SI BY A MODIFIED RADIOFREQUENCY MAGNETRON SPUTTERING TECHNIQUE/

Bi-layered ferroelectric SrBi2Ta2O9 (SBT) films were successfully depo sited on Pt/SiO2/Si. substrates using a sintered SrBi2Ta2O9 ceramic ta rget, and Pi and Ta metal targets by a modified rf magnetron sputterin g technique. The ferroelectric properties of the films were greatly de pendent on the bismuth sputtering power. The SET films deposited under the conditions of rf power of 100 W, Bi de power of 25 W, and Ta de p ower of 10 W showed a dense and uniform microstructure. A remanent pol arization, P-r, of 7.51 mu C/cm(2) and a coercive field E-c, of 28 kV/ cm were obtained for an excitation voltage of 5 V. The SET films show practically no polarization fatigue after 7 x 10(10) switching cycles. Their retention characteristics look very promising up to 10(6) sec. (C) 1998 American Vacuum Society. [S0734-2101(98)10004-0].