Atomic Layer Deposition and Electrical Properties of SrTiO[sub 3] Thin Films Grown Using Sr(C[sub 11]H[sub 19]O[sub 2])[sub 2], Ti(Oi-C[sub 3]H[sub 7])[sub 4], and H[sub 2]O

Abstract

Atomic layer deposited (STO) thin films were grown using and with a remote plasma activated or thermal vapor as oxidant at growth temperatures ranging from . The as-grown films were amorphous and showed a low effective dielectric constant of with a low leakage current density ( at ). The chemical binding status of the Sr ions varied with the degree of crystallization of the STO film. A reasonable film growth rate and stoichiometric cation composition were obtained when the vaporization temperature of Sr-precursor was with the thermal vapor. The low density of the as-grown film induced a large shrinkage in the film thickness which caused microcracking of the crystallized films during postannealing, even with the increased supply. Adoption of thin crystallized seed layer before the main layer STO growth improved the microstructure after the crystallization and the leakage current performance. As a result of the process optimization, the best electrical properties of an STO film grown on a Ru electrode were for the equivalent oxide thickness and for the leakage current density at .