Properties of HfO2 and HfO2: Y films grown by atomic layer deposition in an advanced monocyclopentadienyl-based process

Uniform HfO2 and HfO2:Y (7–8 cat.% Y) thin films were grown from a novel cyclopentadienyl-alkylamido precursor CpHf(NMe2)3, (CpMe)3Y and O3 at 300 °C. HfO2:Y films possessed somewhat higher roughness, and crystallized upon annealing at 500 °C in the form of cubic or tetragonal polymorph, compared to monoclinic HfO2 films. HfO2:Y demonstrated lower capacitance equivalent oxide thickness compared to HfO2, although HfO2films occurred slightly better insulating. Higher capacitance required intense crystallization achieved in the films grown to thicknesses exceeding 6 nm.