Ex situ growth of the c-axis preferred oriented SrBi2Ta2O9 thin films on Pt/Ti/SiO2/Si substrates

SrBi2Ta2O9 (SBT) thin films were deposited on (111) oriented Pt bottom elec trodes using the rf magnetron sputtering method and then postannealed at 65 0-800 degrees C for 30 min in different oxygen atmospheres. The effect of B i content on the c-axis preferred oriented growth was confirmed by the cont rol of the Bi2O3 loss during the postannealing. With increasing Bi content in SBT thin films, the degree of the c-axis preferred orientation was enhan ced. In addition, a bimodal grain size distribution due to the Sr deficienc y in the SBT film was observed. It is suggested that the c-axis preferred o riented growth on Pt(111) bottom electrodes can be attributed to growth con trolled by surface energy minimization. (C) 1999 American Vacuum Society. [ S0734-2101(99)03705-7].