A ruthenium gate for a lanthanide oxide dielectric layer and a method of fabricating such a combination gate and dielectric layer produce a reliable structure for use in a variety of electronic devices. The lanthanide oxide dielectric layer is formed by depositing lanthanum by atomic layer deposition onto a substrate surface using a trisethylcyclopentadionatolanthanum precursor or a trisdipyvaloylmethanatolanthanum precursor. A ruthenium or a conductive ruthenium oxide gate may be formed on the lanthanide oxide dielectric layer. A ruthenium gate on a lanthanide oxide dielectric layer provides a gate structure that effectively prevents a reaction between the gate and the lanthanide oxide dielectric layer.