Piezoelectric ultrathin BaTiO3 films

Ultrathin (about 3 nm thick) BaTiO3 films were deposited by rf sputtering on a Si(100) substrate. LaNiO3 thin films were used as bottom and top conductive electrodes. The BaTiO3 films show piezoelectric behavior characterized by a coefficient d31=−1.8pC∕N. The BaTiO3 films have an extremely high resistance to electrical breakdown up to a field of about 200 MV/cm.