Low-temperature process to improve the leakage current of (Ba, Sr)TiO3 films on Pt/TiN/Ti/Si substrates

In this study, we employed an oxygen plasma post-treatment to improve the l eakage characteristics of Pt/(Ba, Sr)TiO3(BST)/Pt capacitors prepared by th e RF cosputtering technique. Applying oxygen plasma treatment to BST thin f ilms can effectively passivate the oxygen vacancies of the BST films, thus decreasing the electric conduction paths of leakage current. The leakage cu rrent is reduced by as many as two orders of magnitude by this low-temperat ure (250 degreesC) and short duration (similar to5 min) process. However, t he usage of oxygen plasma treatment is not unrestricted. Plasma treatment o ver a long time (more than 10 min) degrades the leakage characteristics, du e to plasma damage. Therefore, a proper oxygen plasma treatment for as-depo sited BST films is desired to improve leakage characteristics of BST thin f ilms.