Composition-Structure-Dielectric Property of Yttrium-Doped Hafnium Oxide Films Deposited by Atomic Layer Deposition

Sequential atomic layer deposition was used to deposit yttrium-doped hafnium oxide films with variable yttrium content using tris(ethylcyclopentadienyl) yttrium and tetrakis(diethylamino) hafnium as metal precursors and water vapor as the oxidizer. The structure and electrical properties of the resulting films were analyzed after different postdeposition annealing conditions to assess composition-structure-dielectric property relationships. The 2.5-100% yttrium-doped films annealed above for consistently yielded cubic- structures. However, there was a strong compositional effect on the dielectric constant, which maximized at yttrium content. The films studied had a leakage current density of or less at .