EFFECTS OF BOTTOM ELECTRODES ON THE LEAKAGE PROPERTIES OF SPUTTERED BST THIN-FILMS

Current-voltage characteristics and time-dependent leakage current beh avior of (Ba,Sr)TiO3 (BST) thin films deposited by rf magnetron sputte ring have been studied in order to identify the effects of bottom elec trodes on leakage properties of BST capacitors. RuO2, Pt and Pt/RuO2 h ybrid bottom electrodes were prepared by de magnetron sputtering and t hermal MOCVD. From comparison of time-dependent electrical properties of the films deposited on the various bottom electrodes, the material of bottom electrode is responsible for the observed dielectric relaxat ion phenomenon, regardless of leakage current level and conduction typ e of the BST capacitors.