For future generations of non-volatile memory applications, the replacement of the interpoly dielectric by a suitable high-k material is required. Rare-earth aluminates are potential candidates because they are predicted to combine a high dielectric permittivity with a large band gap. We demonstrate the atomic layer deposition (ALD) of Gd x Al 2-x O 3 layers using Gd(

GdxHf1−xnormalOy thin films were deposited by atomic layer deposition (ALD) using tris(isopropyl-cyclopentadienyl) gadolinium [Gd(normalPirCp)3] and HfCl4 in combination with normalH2O as an oxidizer. Growth curves showed a nearly ideal ALD behavior. The growth per individual Gd(normalPirCp)3/normalH2O or HfCl4/normalH2O cycle was 0.55 Å, independent of the Gd/(Gd+Hf) composition x in the studied range. This indicates that the amount of HfO2 deposited during a HfCl4/normalH2O cycle was essentially identical to the amount of Gd2normalO3 deposited during a Gd(normalPirCp)3/normalH2O cycle, assuming identical atomic densities of the films independent of composition. The crystallization of GdxHf1−xnormalOy with Gd/(Gd+Hf) contents x between 7 and 30% was studied. Films with x≳10% crystallized into a cubic/tetragonal HfO2 -like phase during spike or laser annealing up to 1300°C , demonstrating that the cubic/tetragonal phase is thermally stable in this temperature range. A maximum dielectric constant of κ∼36 was found for a Gd/(Gd+Hf) concentration of x∼11% .

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