Effects of bottom electrodes (Pt and IrO2) on physical and electrical properties of Bi4-xLaxTi3O12 thin film

Bi3.35La0.85Ti3O12 (BLT) thin (90 nm) films were prepared on Pt (200 nm) an d IrO2 (200 nm) electrodes by metalorganic decomposition (MOD) method, and crystallized by rapid thermal annealing (RTA) and the subsequent furnace an nealing. BLT films were c-axis oriented on both electrodes irrespective of RTA temperature (600 and 700 degreesC). However. the degree of c-axis orien tation was much higher on IrO2 than on Pt, and significantly reduced only o n Pt with decreasing RTA temperature. This result was related to the differ ent stress of BLT film which is negligible on Pt, but 500 MPa (tensile) on lrO(2) in the RTA temperature range of 600-700 degreesC. The crystalline or ientation of BLT film directly affected switching polarization (P* - P) whi ch had much smaller value of 5 muC/cm(2) on IrO2 than 12 muC/cm(2) on Pt, a nd was increased to 16 muC/cm(2) only on Pt with the decrease of RTA temper ature. On the other hand, leakage characteristics were not changed with bot tom electrode materials.